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Sample records for method shows potential

  1. Mining by-products show potential

    International Nuclear Information System (INIS)

    Douglas, Grant

    2013-01-01

    Full text: Many mining and industrial processes generate wastewater that contains a variety of contaminants, such as metals and metalloids. These must be removed to ensure the wastewater is suitable for reuse or safe discharge to the environment. However, mining wastewater treatment processes have traditionally been difficult due to the large range of different contaminants present, requiring a number of complex steps. In current processes, the mining industry generally adds lime to the wastewater to purify it. While often effective, the key issue with this method has been the volume of sludge that forms and the subsequent problems with dealing with this sludge - either to extract the contained water, which often requires additional treatment, or to find enough space for long-term disposal. This complex practice could end soon thanks to a new treatment solution that utilises hydrotalcites. Developed by CSIRO, the treatment overcomes the complexities of lime-based methods and offers a simpler and more water smart process. The CSIRO team found that hydrotalcites, which are layered minerals consisting of aluminium- and magnesium- rich layers, can simultaneously remove a variety of contaminants in wastewater in a single step. Scientists noticed that hydrotalcites begin to form when aluminium and magnesium are present at an ideal ratio and under conditions during neutralisation of acidic waters. As hydrotalcites form, the contaminants become trapped and are easily removed from the wastewater as a solid. Mining wastewater often contains substantial magnesium and aluminium concentrations. This means that we can create hydrotalcites utilising common contaminants that are already present in the wastewater, by simply adjusting their concentrations and adding alkaline compounds to rapidly increase pH. Initial applications have focussed on treating wastewater generated from the mining and extraction of uranium. A range of contaminants including uranium, rare earth elements

  2. Monoclonal Antibody Shows Promise as Potential Therapeutic for MERS | Poster

    Science.gov (United States)

    A monoclonal antibody has proven effective in preventing Middle Eastern Respiratory Syndrome (MERS) in lab animals, suggesting further development as a potential intervention for the deadly disease in humans, according to new research. MERS is a newly emerged coronavirus first detected in humans in 2012. Most cases have occurred in the Middle East, but the disease has appeared elsewhere. In all, MERS has infected more than 1,700 individuals and killed more than 600, according to the World Health Organization. No vaccines or antiviral therapies currently exist. Several candidate vaccines are being developed, and some have been tested in animal models, a prerequisite to human clinical trials.

  3. VAN method of short-term earthquake prediction shows promise

    Science.gov (United States)

    Uyeda, Seiya

    Although optimism prevailed in the 1970s, the present consensus on earthquake prediction appears to be quite pessimistic. However, short-term prediction based on geoelectric potential monitoring has stood the test of time in Greece for more than a decade [VarotsosandKulhanek, 1993] Lighthill, 1996]. The method used is called the VAN method.The geoelectric potential changes constantly due to causes such as magnetotelluric effects, lightning, rainfall, leakage from manmade sources, and electrochemical instabilities of electrodes. All of this noise must be eliminated before preseismic signals are identified, if they exist at all. The VAN group apparently accomplished this task for the first time. They installed multiple short (100-200m) dipoles with different lengths in both north-south and east-west directions and long (1-10 km) dipoles in appropriate orientations at their stations (one of their mega-stations, Ioannina, for example, now has 137 dipoles in operation) and found that practically all of the noise could be eliminated by applying a set of criteria to the data.

  4. Survey Shows Variation in Ph.D. Methods Training.

    Science.gov (United States)

    Steeves, Leslie; And Others

    1983-01-01

    Reports on a 1982 survey of journalism graduate studies indicating considerable variation in research methods requirements and emphases in 23 universities offering doctoral degrees in mass communication. (HOD)

  5. How the Television Show "Mythbusters" Communicates the Scientific Method

    Science.gov (United States)

    Zavrel, Erik; Sharpsteen, Eric

    2016-01-01

    The importance of understanding and internalizing the scientific method can hardly be exaggerated. Unfortunately, it is all too common for high school--and even university--students to graduate with only a partial or oversimplified understanding of what the scientific method is and how to actually employ it. Help in remedying this situation may…

  6. Method for depth referencing hydrocarbon gas shows on mud logs

    International Nuclear Information System (INIS)

    Dion, E.P.

    1986-01-01

    A method is described for identifying hydrocarbon formations surrounding a borehole, comprising the steps of: a. measuring hydrocarbon gas in the entrained formation cuttings obtained during drilling operations in which a drilling mud is continually circulated past a drill bit to carry the cuttings to the earth's surface, b. simultaneously measuring natural gamma radiation in the cuttings, c. identifying the depths at which the cuttings were obtained within the borehole, d. measuring natural gamma radiation within the borehole following completion of the drilling operations, e. correlating the natural gamma radiation measurements in steps (b) and (d), and f. identifying the depths within the borehole from which the entrained cuttings containing hydrocarbon gas were obtained during drilling operations when there is correlation between the natural gamma radiation measurements in steps (b) and (d)

  7. Text Mining of the Classical Medical Literature for Medicines That Show Potential in Diabetic Nephropathy

    Directory of Open Access Journals (Sweden)

    Lei Zhang

    2014-01-01

    Full Text Available Objectives. To apply modern text-mining methods to identify candidate herbs and formulae for the treatment of diabetic nephropathy. Methods. The method we developed includes three steps: (1 identification of candidate ancient terms; (2 systemic search and assessment of medical records written in classical Chinese; (3 preliminary evaluation of the effect and safety of candidates. Results. Ancient terms Xia Xiao, Shen Xiao, and Xiao Shen were determined as the most likely to correspond with diabetic nephropathy and used in text mining. A total of 80 Chinese formulae for treating conditions congruent with diabetic nephropathy recorded in medical books from Tang Dynasty to Qing Dynasty were collected. Sao si tang (also called Reeling Silk Decoction was chosen to show the process of preliminary evaluation of the candidates. It had promising potential for development as new agent for the treatment of diabetic nephropathy. However, further investigations about the safety to patients with renal insufficiency are still needed. Conclusions. The methods developed in this study offer a targeted approach to identifying traditional herbs and/or formulae as candidates for further investigation in the search for new drugs for modern disease. However, more effort is still required to improve our techniques, especially with regard to compound formulae.

  8. Visual evoked potentials show strong positive association with intracranial pressure in patients with cryptococcal meningitis

    Directory of Open Access Journals (Sweden)

    Marcelo Adriano da Cunha Silva Vieira

    2015-04-01

    Full Text Available Objective : To verify the relationship between intracranial pressure and flash visual evoked potentials (F-VEP in patients with cryptococcal meningitis. Method The sample included adults diagnosed with cryptococcal meningitis admitted at a reference hospital for infectious diseases. The patients were subjected to F-VEP tests shortly before lumbar puncture. The Pearson’s linear correlation coefficient was calculated and the linear regression analysis was performed. Results : Eighteen individuals were subjected to a total of 69 lumbar punctures preceded by F-VEP tests. At the first lumbar puncture performed in each patient, N2 latency exhibited a strong positive correlation with intracranial pressure (r = 0.83; CI = 0.60 - 0.94; p < 0.0001. The direction of this relationship was maintained in subsequent punctures. Conclusion : The intracranial pressure measured by spinal tap manometry showed strong positive association with the N2 latency F-VEP in patients with cryptococcal meningitis.

  9. Lichen-derived compounds show potential for central nervous system therapeutics.

    Science.gov (United States)

    Reddy, R Gajendra; Veeraval, Lenin; Maitra, Swati; Chollet-Krugler, Marylène; Tomasi, Sophie; Dévéhat, Françoise Lohézic-Le; Boustie, Joël; Chakravarty, Sumana

    2016-11-15

    Natural products from lichens are widely investigated for their biological properties, yet their potential as central nervous system (CNS) therapeutic agents is less explored. The present study investigated the neuroactive properties of selected lichen compounds (atranorin, perlatolic acid, physodic acid and usnic acid), for their neurotrophic, neurogenic and acetylcholine esterase (AChE) activities. Neurotrophic activity (neurite outgrowth) was determined using murine neuroblastoma Neuro2A cells. A MTT assay was performed to assess the cytotoxicity of compounds at optimum neurotrophic activity. Neuro2A cells treated with neurotrophic lichen compounds were used for RT-PCR to evaluate the induction of genes that code for the neurotrophic markers BDNF and NGF. Immunoblotting was used to assess acetyl H3 and H4 levels, the epigenetic markers associated with neurotrophic and/or neurogenic activity. The neurogenic property of the compounds was determined using murine hippocampal primary cultures. AChE inhibition activity was performed using a modified Ellman's esterase method. Lichen compounds atranorin, perlatolic acid, physodic acid and (+)-usnic acid showed neurotrophic activity in a preliminary cell-based screening based on Neuro2A neurite outgrowth. Except for usnic acid, no cytotoxic effects were observed for the two depsides (atranorin and perlatolic acid) and the alkyl depsidone (physodic acid). Perlatolic acid appears to be promising, as it also exhibited AChE inhibition activity and potent proneurogenic activity. The neurotrophic lichen compounds (atranorin, perlatolic acid, physodic acid) modulated the gene expression of BDNF and NGF. In addition, perlatolic acid showed increased protein levels of acetyl H3 and H4 in Neuro2A cells. These lichen depsides and depsidones showed neuroactive properties in vitro (Neuro2A cells) and ex vivo (primary neural stem or progenitor cells), suggesting their potential to treat CNS disorders. Copyright © 2016 Elsevier Gmb

  10. Investigating CSI: portrayals of DNA testing on a forensic crime show and their potential effects.

    Science.gov (United States)

    Ley, Barbara L; Jankowski, Natalie; Brewer, Paul R

    2012-01-01

    The popularity of forensic crime shows such as CSI has fueled debate about their potential social impact. This study considers CSI's potential effects on public understandings regarding DNA testing in the context of judicial processes, the policy debates surrounding crime laboratory procedures, and the forensic science profession, as well as an effect not discussed in previous accounts: namely, the show's potential impact on public understandings of DNA and genetics more generally. To develop a theoretical foundation for research on the "CSI effect," it draws on cultivation theory, social cognitive theory, and audience reception studies. It then uses content analysis and textual analysis to illuminate how the show depicts DNA testing. The results demonstrate that CSI tends to depict DNA testing as routine, swift, useful, and reliable and that it echoes broader discourses about genetics. At times, however, the show suggests more complex ways of thinking about DNA testing and genetics.

  11. New method for rearing Spodoptera frugiperda in laboratory shows that larval cannibalism is not obligatory

    Directory of Open Access Journals (Sweden)

    Cherre Sade Bezerra Da Silva

    2013-09-01

    Full Text Available New method for rearing Spodoptera frugiperda in laboratory shows that larval cannibalism is not obligatory. Here we show, for the first time, that larvae of the fall armyworm (FAW, Spodoptera frugiperda (Lepidoptera, Noctuidae, can be successfully reared in a cohort-based manner with virtually no cannibalism. FAW larvae were reared since the second instar to pupation in rectangular plastic containers containing 40 individuals with a surprisingly ca. 90% larval survivorship. Adult females from the cohort-based method showed fecundity similar to that already reported on literature for larvae reared individually, and fertility higher than 99%, with the advantage of combining economy of time, space and material resources. These findings suggest that the factors affecting cannibalism of FAW larvae in laboratory rearings need to be reevaluated, whilst the new technique also show potential to increase the efficiency of both small and mass FAW rearings.

  12. Green fabricated CuO nanobullets via Olea europaea leaf extract shows auspicious antimicrobial potential.

    Science.gov (United States)

    Maqbool, Qaisar; Iftikhar, Sidra; Nazar, Mudassar; Abbas, Fazal; Saleem, Asif; Hussain, Talib; Kausar, Rizwan; Anwaar, Sadaf; Jabeen, Nyla

    2017-06-01

    In present investigation, copper oxide (CuO) nanostructures have been prepared via green chemistry. Olea europaea leaf extract act as strong chelating agent for tailoring physical as well as bio-medical characteristics of CuO at the nano-size. Physical characterisation such as scanning electron microscope analysis depicts the formation of homogenised spherical shape nanoparticles (NPs) with average size of 42 nm. X-ray diffraction and Fourier transform infrared spectroscopy further confirmed the crystalline pure phase and monoclinic structure. High performance liquid chromatography (HPLC) testing is performed to evaluate the relative concentration of bioactive molecules in the O. europaea leaf extract. From HPLC results capping action of organic molecules around CuO-NPs is hypothesised. The antimicrobial potency of biosynthesised CuO-NPs have been evaluated using colony forming unit (CFU) counting assay and disc diffusion method which shows a significant zone of inhibition against bacterial and fungal strains may be highly potential for future antimicrobial pharmaceutics. Furthermore, reduction of various precursors by plant extract will reduce environmental impact over chemical synthesis.

  13. A mechanical wave system to show waveforms similar to quantum mechanical wavefunctions in a potential

    International Nuclear Information System (INIS)

    Faletič, Sergej

    2015-01-01

    Interviews with students suggest that even though they understand the formalism and the formal nature of quantum theory, they still often desire a mental picture of what the equations describe and some tangible experience with the wavefunctions. Here we discuss a mechanical wave system capable of reproducing correctly a mechanical equivalent of a quantum system in a potential, and the resulting waveforms in principle of any form. We have successfully reproduced the finite potential well, the potential barrier and the parabolic potential. We believe that these mechanical waveforms can provide a valuable experience base for introductory students to start from. We aim to show that mechanical systems that are described with the same mathematics as quantum mechanical, indeed behave in the same way. We believe that even if treated purely as a wave phenomenon, the system provides much insight into wave mechanics. This can be especially useful for physics teachers and others who often need to resort to concepts and experience rather than mathematics when explaining physical phenomena. (paper)

  14. Silver Nanoparticles Synthesized Using Wild Mushroom Show Potential Antimicrobial Activities against Food Borne Pathogens

    Directory of Open Access Journals (Sweden)

    Yugal Kishore Mohanta

    2018-03-01

    Full Text Available The present study demonstrates an economical and eco-friendly method for the synthesis of silver nanoparticles (AgNPs using the wild mushroom Ganoderma sessiliforme. The synthesis of AgNPs was confirmed and the products characterized by UV-visible spectroscopy, dynamic light scattering spectroscopy and X-ray diffraction analysis. Furthermore, Fourier transform infrared spectroscopy (ATR-FTIR analysis was performed to identify the viable biomolecules involved in the capping and active stabilization of AgNPs. Moreover, the average sizes and morphologies of AgNPs were analyzed by field emission scanning electron microscopy (FE-SEM. The potential impacts of AgNPs on food safety and control were evaluated by the antimicrobial activity of the synthesized AgNPs against common food-borne bacteria, namely, Escherichia coli, Bacillus subtilis, Streptococcus faecalis, Listeria innocua and Micrococcus luteus. The results of this study revealed that the synthesized AgNPs can be used to control the growth of food-borne pathogens and have potential application in the food packaging industry. Moreover, the AgNPs were evaluated for antioxidant activity (DPPH, for biocompatibility (L-929, normal fibroblast cells, and for cytotoxic effects on human breast adenosarcoma cells (MCF-7 & MDA-MB231 to highlight their potential for use in a variety of bio-applications.

  15. Strains of the soil fungus Mortierella show different degradation potentials for the phenylurea herbicide diuron.

    Science.gov (United States)

    Ellegaard-Jensen, Lea; Aamand, Jens; Kragelund, Birthe B; Johnsen, Anders H; Rosendahl, Søren

    2013-11-01

    Microbial pesticide degradation studies have until now mainly focused on bacteria, although fungi have also been shown to degrade pesticides. In this study we clarify the background for the ability of the common soil fungus Mortierella to degrade the phenylurea herbicide diuron. Diuron degradation potentials of five Mortierella strains were compared, and the role of carbon and nitrogen for the degradation process was investigated. Results showed that the ability to degrade diuron varied greatly among the Mortierella strains tested, and the strains able to degrade diuron were closely related. Degradation of diuron was fastest in carbon and nitrogen rich media while suboptimal nutrient levels restricted degradation, making it unlikely that Mortierella utilize diuron as carbon or nitrogen sources. Degradation kinetics showed that diuron degradation was followed by formation of the metabolites 1-(3,4-dichlorophenyl)-3-methylurea, 1-(3,4-dichlorophenyl)urea and an hitherto unknown metabolite suggested to be 1-(3,4-dichlorophenyl)-3-methylideneurea.

  16. Strains of the soil fungus Mortierella show different degradation potentials for the phenylurea herbicide diuron

    DEFF Research Database (Denmark)

    Ellegaard-Jensen, Lea; Aamand, Jens; Kragelund, Birthe Brandt

    2013-01-01

    Microbial pesticide degradation studies have until now mainly focused on bacteria, although fungi have also been shown to degrade pesticides. In this study we clarify the background for the ability of the common soil fungus Mortierella to degrade the phenylurea herbicide diuron. Diuron degradation...... potentials of five Mortierella strains were compared, and the role of carbon and nitrogen for the degradation process was investigated. Results showed that the ability to degrade diuron varied greatly among the Mortierella strains tested, and the strains able to degrade diuron were closely related....... Degradation of diuron was fastest in carbon and nitrogen rich media while suboptimal nutrient levels restricted degradation, making it unlikely that Mortierella utilize diuron as carbon or nitrogen sources. Degradation kinetics showed that diuron degradation was followed by formation of the metabolites 1...

  17. Cardiac action potential repolarization revisited: early repolarization shows all-or-none behaviour.

    Science.gov (United States)

    Trenor, Beatriz; Cardona, Karen; Saiz, Javier; Noble, Denis; Giles, Wayne

    2017-11-01

    In healthy mammalian hearts the action potential (AP) waveform initiates and modulates each contraction, or heartbeat. As a result, AP height and duration are key physiological variables. In addition, rate-dependent changes in ventricular AP duration (APD), and variations in APD at a fixed heart rate are both reliable biomarkers of electrophysiological stability. Present guidelines for the likelihood that candidate drugs will increase arrhythmias rely on small changes in APD and Q-T intervals as criteria for safety pharmacology decisions. However, both of these measurements correspond to the final repolarization of the AP. Emerging clinical evidence draws attention to the early repolarization phase of the action potential (and the J-wave of the ECG) as an additional important biomarker for arrhythmogenesis. Here we provide a mechanistic background to this early repolarization syndrome by summarizing the evidence that both the initial depolarization and repolarization phases of the cardiac action potential can exhibit distinct time- and voltage-dependent thresholds, and also demonstrating that both can show regenerative all-or-none behaviour. An important consequence of this is that not all of the dynamics of action potential repolarization in human ventricle can be captured by data from single myocytes when these results are expressed as 'repolarization reserve'. For example, the complex pattern of cell-to-cell current flow that is responsible for AP conduction (propagation) within the mammalian myocardium can change APD and the Q-T interval of the electrocardiogram alter APD stability, and modulate responsiveness to pharmacological agents (such as Class III anti-arrhythmic drugs). © 2017 The Authors. The Journal of Physiology © 2017 The Physiological Society.

  18. Potential Antioxidant Anthraquinones Isolated from Rheum emodi Showing Nematicidal Activity against Meloidogyne incognita

    Directory of Open Access Journals (Sweden)

    Brijesh Tripathi

    2014-01-01

    Full Text Available Antioxidant and nematicidal properties were evaluated for R. emodi extractives which are extracted by standardizing and adopting accelerated solvent extraction (ASE method along with traditional Soxhlet extraction. The extracted material was separated using flash chromatography and the separation conditions and solvents were standardized for the extracted plant constituents. The purity was detected by using analytical reverse phase high pressure liquid chromatography (HPLC. LC-MS/MS detection in the direct infusion mode of the isolated, purified products afforded four anthraquinones, characterized by their infrared spectra (IR and 1H spectra as chrysophanol, physcion, emodin, and aloe-emodin. Five antraquinone glucoside derivatives and piceatannol-3-O-β-d-glucopyranoside have also been detected from the extracted product. During in vitro evaluation the antioxidant potential of methanolic crude extract (CE1 was the highest, followed by ethyl acetate crude extract (CE2 and chloroform extract (CE3 in DPPH radical scavenging activity. The CE1 also demonstrated outstanding nematicidal activity as compared with other extracts, pure anthraquinones, and even positive control azadirachtin. The study conclusively demonstrated the antioxidant potential of R. emodi extracts and also its ability in extenuating the Meloidogyne incognita (root-knot nematode. The bioassay results can be extrapolated to actual field condition and clinical studies.

  19. Map showing radon potential of rocks and soils in Montgomery County, Maryland

    Science.gov (United States)

    Gundersen, L.C.; Reimer, G.M.; Wiggs, C.R.; Rice, C.A.

    1988-01-01

    This report summarizes the radon potential of Montgomery County in the context of its geology. Radon is a naturally occurring gas produced by the radioactive decay of uranium. Radon produced by uraniferous rocks and soils may enter a house through porous building materials and through openings in walls and floors. Radon gases has a tendency to move from the higher pressure commonly existing in the soil to the lower pressure commonly existing in the house. The U.S. Environmental Protection Agency (U.S. EPA, 1986a) estimates that elevated levels of indoor radon may be associated with 5,000 to 20,000 of the 130,000 lung cancer deaths per year. They also estimate that 8 to 12 percent of the homes in the United States will have annual average indoor radon levels exceeding 4 picoCuries per liter of air (pCi/L). Above this level, the U.S. EPA recommends homeowners take remedial action. May factors control the amount of radon which may enter a home from the geologic environment. Soil drainage, permeability, and moisture content effect the amount of radon that can be released from rocks and soils (known as the emmanation) and may limit or increase how far it can migrate. Well drained, highly permeable soils facilitate the movement of radon. Soils with water content in the 8 to 15 percent range enhance the emmanation of radon (Lindmark, 1985). Daily and seasonal variations in soil and indoor radon can be caused by meteorologic factors such as barometric pressure, temperature, and wind (Clements and Wilkening, 1974; Schery and other, 1984). Construction practices also inhibit or promote entry of radon into the home (U.S. EPA, 1986b). In general, however, geology controls the source and distribution of radon (Akerblom and Wilson, 1982; Gundersen and others, 1987, 1988; Sextro and others, 1987; U.S. EPA, 1983; Peake, 1988; Peake and Hess, 1988). The following sections describe: 1) the methods used to measure radon and equivalent uranium (eU) in soil; 2) the radon potential

  20. Urine proteome analysis in Dent's disease shows high selective changes potentially involved in chronic renal damage.

    Science.gov (United States)

    Santucci, Laura; Candiano, Giovanni; Anglani, Franca; Bruschi, Maurizio; Tosetto, Enrica; Cremasco, Daniela; Murer, Luisa; D'Ambrosio, Chiara; Scaloni, Andrea; Petretto, Andrea; Caridi, Gianluca; Rossi, Roberta; Bonanni, Alice; Ghiggeri, Gian Marco

    2016-01-01

    Definition of the urinary protein composition would represent a potential tool for diagnosis in many clinical conditions. The use of new proteomic technologies allows detection of genetic and post-trasductional variants that increase sensitivity of the approach but complicates comparison within a heterogeneous patient population. Overall, this limits research of urinary biomarkers. Studying monogenic diseases are useful models to address this issue since genetic variability is reduced among first- and second-degree relatives of the same family. We applied this concept to Dent's disease, a monogenic condition characterised by low-molecular-weight proteinuria that is inherited following an X-linked trait. Results are presented here on a combined proteomic approach (LC-mass spectrometry, Western blot and zymograms for proteases and inhibitors) to characterise urine proteins in a large family (18 members, 6 hemizygous patients, 6 carrier females, and 6 normals) with Dent's diseases due to the 1070G>T mutation of the CLCN5. Gene ontology analysis on more than 1000 proteins showed that several clusters of proteins characterised urine of affected patients compared to carrier females and normal subjects: proteins involved in extracellular matrix remodelling were the major group. Specific analysis on metalloproteases and their inhibitors underscored unexpected mechanisms potentially involved in renal fibrosis. Studying with new-generation techniques for proteomic analysis of the members of a large family with Dent's disease sharing the same molecular defect allowed highly repetitive results that justify conclusions. Identification in urine of proteins actively involved in interstitial matrix remodelling poses the question of active anti-fibrotic drugs in Dent's patients. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Iterated interactions method. Realistic NN potential

    International Nuclear Information System (INIS)

    Gorbatov, A.M.; Skopich, V.L.; Kolganova, E.A.

    1991-01-01

    The method of iterated potential is tested in the case of realistic fermionic systems. As a base for comparison calculations of the 16 O system (using various versions of realistic NN potentials) by means of the angular potential-function method as well as operators of pairing correlation were used. The convergence of genealogical series is studied for the central Malfliet-Tjon potential. In addition the mathematical technique of microscopical calculations is improved: new equations for correlators in odd states are suggested and the technique of leading terms was applied for the first time to calculations of heavy p-shell nuclei in the basis of angular potential functions

  2. Soil bacteria showing a potential of chlorpyrifos degradation and plant growth enhancement

    Directory of Open Access Journals (Sweden)

    Shamsa Akbar

    Full Text Available ABSTRACT Background: Since 1960s, the organophosphate pesticide chlorpyrifos has been widely used for the purpose of pest control. However, given its persistence and toxicity towards life forms, the elimination of chlorpyrifos from contaminated sites has become an urgent issue. For this process bioremediation is the method of choice. Results: Two bacterial strains, JCp4 and FCp1, exhibiting chlorpyrifos-degradation potential were isolated from pesticide contaminated agricultural fields. These isolates were able to degrade 84.4% and 78.6% of the initial concentration of chlorpyrifos (100 mg L-1 within a period of only 10 days. Based on 16S rRNA sequence analysis, these strains were identified as Achromobacter xylosoxidans (JCp4 and Ochrobactrum sp. (FCp1. These strains exhibited the ability to degrade chlorpyrifos in sterilized as well as non-sterilized soils, and were able to degrade 93-100% of the input concentration (200 mg kg-1 within 42 days. The rate of degradation in inoculated soils ranged from 4.40 to 4.76 mg-1 kg-1 d-1 with rate constants varying between 0.047 and 0.069 d-1. These strains also displayed substantial plant growth promoting traits such as phosphate solubilization, indole acetic acid production and ammonia production both in absence as well as in the presence of chlorpyrifos. However, presence of chlorpyrifos (100 and 200 mg L-1 was found to have a negative effect on indole acetic acid production and phosphate solubilization with percentage reduction values ranging between 2.65-10.6% and 4.5-17.6%, respectively. Plant growth experiment demonstrated that chlorpyrifos has a negative effect on plant growth and causes a decrease in parameters such as percentage germination, plant height and biomass. Inoculation of soil with chlorpyrifos-degrading strains was found to enhance plant growth significantly in terms of plant length and weight. Moreover, it was noted that these strains degraded chlorpyrifos at an increased rate (5

  3. Soil bacteria showing a potential of chlorpyrifos degradation and plant growth enhancement.

    Science.gov (United States)

    Akbar, Shamsa; Sultan, Sikander

    2016-01-01

    Since 1960s, the organophosphate pesticide chlorpyrifos has been widely used for the purpose of pest control. However, given its persistence and toxicity towards life forms, the elimination of chlorpyrifos from contaminated sites has become an urgent issue. For this process bioremediation is the method of choice. Two bacterial strains, JCp4 and FCp1, exhibiting chlorpyrifos-degradation potential were isolated from pesticide contaminated agricultural fields. These isolates were able to degrade 84.4% and 78.6% of the initial concentration of chlorpyrifos (100mgL(-1)) within a period of only 10 days. Based on 16S rRNA sequence analysis, these strains were identified as Achromobacter xylosoxidans (JCp4) and Ochrobactrum sp. (FCp1). These strains exhibited the ability to degrade chlorpyrifos in sterilized as well as non-sterilized soils, and were able to degrade 93-100% of the input concentration (200mgkg(-1)) within 42 days. The rate of degradation in inoculated soils ranged from 4.40 to 4.76mg(-1)kg(-1)d(-1) with rate constants varying between 0.047 and 0.069d(-1). These strains also displayed substantial plant growth promoting traits such as phosphate solubilization, indole acetic acid production and ammonia production both in absence as well as in the presence of chlorpyrifos. However, presence of chlorpyrifos (100 and 200mgL(-1)) was found to have a negative effect on indole acetic acid production and phosphate solubilization with percentage reduction values ranging between 2.65-10.6% and 4.5-17.6%, respectively. Plant growth experiment demonstrated that chlorpyrifos has a negative effect on plant growth and causes a decrease in parameters such as percentage germination, plant height and biomass. Inoculation of soil with chlorpyrifos-degrading strains was found to enhance plant growth significantly in terms of plant length and weight. Moreover, it was noted that these strains degraded chlorpyrifos at an increased rate (5.69mg(-1)kg(-1)d(-1)) in planted soil. The

  4. Ghrelin receptor (GHS-R1A) agonists show potential as interventive agents during aging.

    Science.gov (United States)

    Smith, Roy G; Sun, Yuxiang; Jiang, Hong; Albarran-Zeckler, Rosie; Timchenko, Nikolai

    2007-11-01

    Administration of an orally active agonist (MK-0677) of the growth hormone secretagogue receptor (GHS-R1a) to elderly subjects restored the amplitude of endogenous episodic growth hormone (GH) release to that of young adults. Functional benefits include increased lean mass and bone density and modest improvements in strength. In old mice, a similar agonist partially restored function to the thymus and reduced tumor cell growth and metastasis. Treatment of old mice with the endogenous GHS-R1a agonist ghrelin restored a young liver phenotype. The mechanism involves inhibition of cyclin D3:cdk4/cdk6 activity and increased protein phosphatase-2A (PP2A) activity in liver nuclei, which stabilizes the dephosphorylated form of the transcription factor C/EBPalpha preventing the age-dependent formation of the C/EBPalpha-Rb-E2F4-Brm nuclear complex. By inhibiting formation of this complex, repression of E2F target genes is de-repressed and C/EBPalpha regulated expression of Pepck, a regulator of gluconeogenesis, is normalized, thereby restoring a young liver phenotype. In the brain, aging is associated with decline in dopamine function. We investigated the potential neuromodulatory role of GHS-R1a on dopamine action. Neurons were identified in the hippocampus, cortex, substantia nigra, and ventral tegmental areas that coexpressed GHS-R1a and dopamine receptor subtype-1 (D1R). Cell culture studies showed that, in the presence of ghrelin and dopamine, GHS-R and D1R form heterodimers, which modified G-protein signal transduction resulting in amplification of dopamine signaling. We speculate that aging is associated with deficient endogenous ghrelin signaling that can be rescued by intervention with GHS-R1a agonists to improve quality of life and maintain independence.

  5. Expanding the Playing Field: Immune-Based Therapy Shows Potential for Lung, Other Cancers

    Science.gov (United States)

    Results from two early-phase clinical trials presented at the 2012 American Society of Clinical Oncology annual meeting provide further evidence that priming the immune system to attack tumors has potential as a treatment for certain cancers.

  6. A mechanically-induced colon cancer cell population shows increased metastatic potential

    KAUST Repository

    Tang, Xin; Kuhlenschmidt, Theresa B; Li, Qian; Ali, Shahjahan; Lezmi, Stephane; Chen, Hong; Pires-Alves, Melissa; Laegreid, William W; Saif, Taher A; Kuhlenschmidt, Mark S

    2014-01-01

    Background: Metastasis accounts for the majority of deaths from cancer. Although tumor microenvironment has been shown to have a significant impact on the initiation and/or promotion of metastasis, the mechanism remains elusive. We previously reported that HCT-8 colon cancer cells underwent a phenotypic transition from an adhesive epithelial type (E-cell) to a rounded dissociated type (R-cell) via soft substrate culture, which resembled the initiation of metastasis. The objective of current study was to investigate the molecular and metabolic mechanisms of the E-R transition.Methods: Global gene expressions of HCT-8 E and R cells were measured by RNA Sequencing (RNA-seq); and the results were further confirmed by real-time PCR. Reactive oxygen species (ROS), anoikis resistance, enzyme activity of aldehyde dehydrogenase 3 family, member A1 (ALDH3A1), and in vitro invasion assay were tested on both E and R cells. The deformability of HCT-8 E and R cells was measured by atomic force microscopy (AFM). To study the in vivo invasiveness of two cell types, athymic nude mice were intra-splenically injected with HCT-8 E or R cells and sacrificed after 9 weeks. Incidences of tumor development and metastasis were histologically evaluated and analyzed with Fisher's exact test.Results: Besides HCT-8, E-R transition on soft substrates was also seen in three other cancer cell lines (HCT116, SW480 colon and DU145 prostate cancer). The expression of some genes, such as ALDH3A1, TNS4, CLDN2, and AKR1B10, which are known to play important roles in cancer cell migration, invasion, proliferation and apoptosis, were increased in HCT-8 R cells. R cells also showed higher ALDH3A1 enzyme activity, higher ROS, higher anoikis resistance, and higher softness than E cells. More importantly, in vitro assay and in vivo animal models revealed that HCT-8 R cells were more invasive than E cells.Conclusions: Our comprehensive comparison of HCT-8 E and R cells revealed differences of molecular

  7. A mechanically-induced colon cancer cell population shows increased metastatic potential

    KAUST Repository

    Tang, Xin

    2014-05-29

    Background: Metastasis accounts for the majority of deaths from cancer. Although tumor microenvironment has been shown to have a significant impact on the initiation and/or promotion of metastasis, the mechanism remains elusive. We previously reported that HCT-8 colon cancer cells underwent a phenotypic transition from an adhesive epithelial type (E-cell) to a rounded dissociated type (R-cell) via soft substrate culture, which resembled the initiation of metastasis. The objective of current study was to investigate the molecular and metabolic mechanisms of the E-R transition.Methods: Global gene expressions of HCT-8 E and R cells were measured by RNA Sequencing (RNA-seq); and the results were further confirmed by real-time PCR. Reactive oxygen species (ROS), anoikis resistance, enzyme activity of aldehyde dehydrogenase 3 family, member A1 (ALDH3A1), and in vitro invasion assay were tested on both E and R cells. The deformability of HCT-8 E and R cells was measured by atomic force microscopy (AFM). To study the in vivo invasiveness of two cell types, athymic nude mice were intra-splenically injected with HCT-8 E or R cells and sacrificed after 9 weeks. Incidences of tumor development and metastasis were histologically evaluated and analyzed with Fisher\\'s exact test.Results: Besides HCT-8, E-R transition on soft substrates was also seen in three other cancer cell lines (HCT116, SW480 colon and DU145 prostate cancer). The expression of some genes, such as ALDH3A1, TNS4, CLDN2, and AKR1B10, which are known to play important roles in cancer cell migration, invasion, proliferation and apoptosis, were increased in HCT-8 R cells. R cells also showed higher ALDH3A1 enzyme activity, higher ROS, higher anoikis resistance, and higher softness than E cells. More importantly, in vitro assay and in vivo animal models revealed that HCT-8 R cells were more invasive than E cells.Conclusions: Our comprehensive comparison of HCT-8 E and R cells revealed differences of molecular

  8. Superfield tadpole method for SUSY effective potential

    International Nuclear Information System (INIS)

    Srivastava, P.P.

    1983-01-01

    Superfield formulation of Weinberg's tadpole method to compute the effective potential in supersymmetric theories is illustrated by considering the general renormalizable action involving only chiral scalar superfields. Unconstrained superfield potentials are introduced to simplify the ''effective'' superfield propagator which is derived in a compact form. (orig.)

  9. Working memory processes show different degrees of lateralization : Evidence from event-related potentials

    NARCIS (Netherlands)

    Talsma, D; Wijers, A.A.; Klaver, P; Mulder, G.

    This study aimed to identify different processes in working memory, using event-related potentials (ERPs) and response times. Abstract polygons were presented for memorization and subsequent recall in a delayed matching-to-sample paradigm. Two polygons were presented bilaterally for memorization and

  10. Potential mechanisms of diet therapy for fibrocystic breast conditions show inadequate evidence of effectiveness.

    Science.gov (United States)

    Horner, N K; Lampe, J W

    2000-11-01

    Fibrocystic breast conditions, formerly referred to as fibrocystic breast disease, affect about half of all women and typically present as any combination of breast nodularity, swelling, and pain. We reviewed the literature to evaluate evidence supporting nutrition interventions commonly recommended for fibrocystic breast conditions by health care providers. Randomized, controlled studies of the effectiveness of caffeine restriction fail to support any benefit in fibrocystic breast conditions. Similarly, evidence supporting evening primrose oil, vitamin E, or pyridoxine as treatments for the discomforts of fibrocystic breast conditions is insufficient to draw conclusions about effectiveness. Dietary alterations that influence the intermediate markers for fibrocystic breast conditions include low-fat (15% to 20% energy), high-fiber (30 g/day), and soy isoflavone regimens. However, our findings provide no solid evidence for secondary prevention or treatment of fibrocystic breast conditions through a dietary approach. Health care providers should limit recommendations to proven diet therapies supported by randomized, placebo-controlled trials, given the instability inherent in fibrocystic breast conditions and the near 20% placebo effect associated with intervention. Because excessive estrogen or altered sensitivity to estrogen is the dominant theory of etiology, interventions that may modulate endogenous steroid hormones warrant further investigation as potential treatments for symptomatic fibrocystic breast conditions.

  11. Coumarin Compounds of Biebersteinia Multifida Roots Show Potential Anxiolytic Effects In Mice

    Directory of Open Access Journals (Sweden)

    Hamid Reza Monsef-Esfahani

    2013-06-01

    Full Text Available Background:Traditional preparations of the root of Biebersteinia multifida DC (Geraniaceae, a native medicinal plant of Irano-Turanian floristic region, have been used for the treatment of phobias as anxiolytic herbal preparation.Methods:We utilized the phobic behavior of mice in an elevated plus-maze as a model to evaluate the anxiolytic effect of the plant extract and bio-guided fractionation was applied to isolate the active compounds. Total root extract, alkaline and ether fraction were administered to mice at different doses 30 and 90 min prior to the maze test. Saline and diazepam were administered as negative and positive controls, respectively. The time spent in open and closed arms, an index of anxiety behavior and entry time, was measured as an index of animal activity.Results:The total root extract exhibited anxiolytic effect which was comparable to diazepam but with longer duration. This sustained effect of the crude extract was sustained for 90 min and was even more after injection of 45 mg/kg while the effect of diazepam had been reduced by 90 min. The anxiolytic effect factor was only present in the alkaline fraction and displayed its effect at lower doses than diazepam while pure vasicinone as the previously known alkaloid did not shown anxiolytic effect. The effect of the alkaline fraction was in a dose dependent manner starting at 0.2 mg/kg with a maximum at 1.0 mg/kg. Bio-guided fractionation using a variety of chromatographic methods led to isolation and purification of three coumarin derivatives from the bioactive fraction, including umbelliferone, scopoletin, and ferulic acid.Conclusion:For the first time, bio-guided fractionation of the root extract of B. multifida indicates significant sustained anxiolytic effects which led to isolation of three coumarin derivatives with well-known potent MAO inhibitory and anti-anxiety effects. These data contribute to evidence-based traditional use of B. multifida root for anxiety

  12. Botanicals and Phosphonate Show Potential to Replace Copper for Control of Potato Late Blight

    Directory of Open Access Journals (Sweden)

    Hans-Rudolf Forrer

    2017-11-01

    Full Text Available Potato late blight (PLB caused by Phytophthora infestans (Pi is the most harmful disease in potato production worldwide. In organic farming, copper is used despite its persistence in soil and toxicity to soil organisms. To replace copper, suspensions of powders from three promising botanicals, including bark of buckthorn (Frangula alnus, FA, roots of medicinal rhubarb (Rheum palmatum and galls of the nutgall tree (Galla chinensis, were tested in multi-year field experiments. The current study shows for the first time that botanicals could replace copper under field conditions and best PLB reduction on leaves was achieved with FA, reaching a level close to that of 2 to 3 kg copper per hectare and year. Better results than with copper were achieved with Phosfik® (Ph, a phosphonate-based product. For both FA and Ph, the mode of action is based on induced resistance, for Ph also on direct fungicidal effects. A disadvantage of Ph is the accumulation of residues in potato tubers. Nevertheless, two to three applications with 2 to 3 L/ha of Ph would be feasible to not exceed a minimal risk level (MLR of 20 mg/kg of phosphorous acid as proposed by the European Food Safety Authority. Due to an excellent environmental profile and a complex mode of action counteracting Pi resistance, phosphonate-based products would be most suitable for sustainable PLB management in integrated pest management (IPM programmes.

  13. Purification and characterization of a beta-Glucanase produced by Trichoderma harzianum showing biocontrol potential

    Directory of Open Access Journals (Sweden)

    Janice Lisboa de Marco

    2007-01-01

    Full Text Available A beta-1,3-glucanase was produced by Trichoderma harzianum in cultures containing chitin as the sole substrate. Two proteins showing beta-1,3-glucanase activity were purified to apparent homogeneity by hydrophobic chromatography. The molecular masses of these proteins were 29 and 36 kDa. The 36 kDa protein was further characterized. It was active on a broad pH range, and maximal activity was detected at pH 5.0. The optimum temperature of the 36 kDa beta-1,3-glucanase was 50ºC, but the purified enzyme was very sensitive to temperature. It lost about 60% or more of the activity after incubation for 30 min at 45, 50 and 60ºC. The apparent K M and Vmax for hydrolysis of laminarin at pH 5.0 and 37ºC, were 0.099 mg of reducing sugar/mL and 0.3 mg of reducing sugar/min.mL, respectively. The enzyme was insensitive to organic compound and metal ions, except for the ferric ion which inhibited about 100% of the original activity at the concentration of 1 mM. In contrast to other hydrolytic enzymes (a chitinase and a protease produced by the same T. harzianum isolate (1051, the beta-1,3-glucanase showed no effect on the cell wall of the phytopathogenic fungus Crinipellis perniciosa.Uma beta-1,3-glucanase foi produzida por Trichoderma harzianum em cultura contendo quitina como fonte de carbono. Duas proteínas com atividade de beta-1,3-glucanase foram purificadas através de cromatografia de interação hidrofóbica. As massas moleculares destas proteínas foram de 29 kDa e 36 kDa. A proteína de 36 kDa foi caracterizada quanto à influência das condições de pH e temperatura. A atividade máxima foi encontrada em pH 5,0 e temperatura de 50ºC. A proteína purificada mostrou-se muito sensível à temperatura. Aproximadamente 60% da atividade original foi perdida por incubação da proteína a 45ºC, 50ºC e 60ºC, por 30 min. O K M aparente e a Vmax para hidrólise de laminarina em pH 5,0 à 37ºC, foram de 0,099 mg de açúcar redutor/mL e 0,3 mg de a

  14. A simple identification method for spore-forming bacteria showing high resistance against γ-rays

    International Nuclear Information System (INIS)

    Koshikawa, Tomihiko; Sone, Koji; Kobayashi, Toshikazu

    1993-01-01

    A simple identification method was developed for spore-forming bacteria which are highly resistant against γ-rays. Among 23 species of Bacillus studied, the spores of Bacillus megaterium, B. cereus, B. thuringiensis, B. pumilus and B. aneurinolyticus showed high resistance against γ-rays as compared with other spores of Bacillus species. Combination of the seven kinds of biochemical tests, namely, the citrate utilization test, nitrate reduction test, starch hydrolysis test, Voges-Proskauer reaction test, gelatine hydrolysis test, mannitol utilization test and xylose utilization test showed a characteristic pattern for each species of Bacillus. The combination pattern of each the above tests with a few supplementary test, if necessary, was useful to identify Bacillus species showing high radiation resistance against γ-rays. The method is specific for B. megaterium, B. thuringiensis and B. pumilus, and highly selective for B. aneurinolyticus and B. cereus. (author)

  15. Phycoremediation as a potential water decontamination method

    International Nuclear Information System (INIS)

    Tatarova, D.; Galanda, D.; Kuruc, J.

    2017-01-01

    In experiments, we focused on the determination of the phycoremediation potential of Chlamydomonas reinhardtii and Scenedesmus obliquus in targeted contaminated aqueous solutions containing radioisotopes 137 Cs and 6 0Co. Microalgae were selected based on their high bioremediation capability. Phycoremediation potential was determined by monitoring the effect of different pH values between pH 2 to pH 9 as well as by monitoring the decrease in activity of the solution over time. Cultivation of microalgae took place in 12 h/12 h light/dark light mode in blue and red light, which promotes plant growth at room temperature. In order to determine the micro-sorption capacity, a method was used to determine the concentration of microns using a Buerker cell in parallel with the spectrophotometric method. (authors)

  16. Different methods to quantify Listeria monocytogenesbiofilms cells showed different profile in their viability

    Directory of Open Access Journals (Sweden)

    Lizziane Kretli Winkelströter

    2015-03-01

    Full Text Available Listeria monocytogenes is a foodborne pathogen able to adhere and to form biofilms in several materials commonly present in food processing plants. The aim of this study was to evaluate the resistance of Listeria monocytogenes attached to abiotic surface, after treatment with sanitizers, by culture method, microscopy and Quantitative Real Time Polymerase Chain Reaction (qPCR. Biofilms of L. monocytogenes were obtained in stainless steel coupons immersed in Brain Heart Infusion Broth, under agitation at 37 °C for 24 h. The methods selected for this study were based on plate count, microscopic count with the aid of viability dyes (CTC-DAPI, and qPCR. Results of culture method showed that peroxyacetic acid was efficient to kill sessile L. monocytogenes populations, while sodium hypochlorite was only partially effective to kill attached L. monocytogenes (p < 0.05. When, viability dyes (CTC/DAPI combined with fluorescence microscopy and qPCR were used and lower counts were found after treatments (p < 0.05. Selective quantification of viable cells of L. monocytogenes by qPCR using EMA revelead that the pre-treatment with EMA was not appropriate since it also inhibited amplification of DNA from live cells by ca. 2 log. Thus, the use of CTC counts was the best method to count viable cells in biofilms.

  17. Indirect methods for wake potential integration

    International Nuclear Information System (INIS)

    Zagorodnov, I.

    2006-05-01

    The development of the modern accelerator and free-electron laser projects requires to consider wake fields of very short bunches in arbitrary three dimensional structures. To obtain the wake numerically by direct integration is difficult, since it takes a long time for the scattered fields to catch up to the bunch. On the other hand no general algorithm for indirect wake field integration is available in the literature so far. In this paper we review the know indirect methods to compute wake potentials in rotationally symmetric and cavity-like three dimensional structures. For arbitrary three dimensional geometries we introduce several new techniques and test them numerically. (Orig.)

  18. Method of angular potential functions. Hypernuclei

    Energy Technology Data Exchange (ETDEWEB)

    Gorbatov, A M [Kalininskij Gosudarstvennyj Univ. USSR

    1979-01-01

    The method of microscopic calculation of hypernuclei with realistic ..lambda..N interaction is developed. It is shown that the ..lambda..+core model and the model of collective motion of the hypernuclear baryons cannot yield correct values of the B/sub ..lambda../-particle separation energy. The first starting point of the method is introduction of the rho collective variable of nucleons and the distance of the ..lambda.. particle from the center-of-inertia of the rho/sub ..lambda../ nucleons (or a universal collective variable which is the same for all particles). The second starting point is the building of the physical bases for the NN and ..lambda..N interaction in the space of multidimensional angles. The convergence of the ..lambda..N potential harmonic expansion is studied for various amplitudes and radii of the ..lambda..N potential with the /sub ..lambda..//sup 5/ He hypernucleous as an example. The ..lambda..-particle induced excitation probability of collective and single-particle degrees of freedom of the core is estimated. The single-particle excitations of zero orbital momentum nucleons are shown to dominate.

  19. A new method of MR total spine imaging for showing the brace effect in scoliosis

    Energy Technology Data Exchange (ETDEWEB)

    Schmitz, A.; Kandyba, J.; Koenig, R.; Jaeger, U.E.; Gieseke, J.; Schmitt, O. [Univ. of Bonn (Germany)

    2001-07-01

    Bracing is a method of early, nonsurgical treatment for scoliosis, but a hypokyphotic effect on the thoracic spine is reported. We developed a magnetic resonance tomography (MR) procedure presenting an image of the whole spine in the coronal and sagittal planes (MR total spine imaging), and studied the brace effect, using this technique. We examined 26 female patients with idiopathic scoliosis treated with a Cheneau brace (mean age, 13.2 years; mean duration of brace treatment at the time of investigation, 1.5 years). The MR examinations were performed with the patient in the supine position with and without the brace in direct sequence. As measured on the coronal MR images, the thoracic curve was corrected, on average, from 29 deg to 22 deg (mean correction, 24%). There was a slight reduction in the sagittal Cobb angle measured between T4 and T12 (mean sagittal Cobb angle without brace, 14 deg ; with brace, 12 deg), which was still a significant change. MR total spine imaging could be a useful tool for studying the brace effect in scoliosis in two planes. Using this technique, we found reduced sagittal Cobb angles for the thoracic kyphosis with brace. Because there is no radiation exposure, the MR procedure has a potential use in the monitoring of brace treatment. (author)

  20. Combined 18F-Fluciclovine PET/MRI Shows Potential for Detection and Characterization of High-Risk Prostate Cancer.

    Science.gov (United States)

    Elschot, Mattijs; Selnæs, Kirsten M; Sandsmark, Elise; Krüger-Stokke, Brage; Størkersen, Øystein; Giskeødegård, Guro F; Tessem, May-Britt; Moestue, Siver A; Bertilsson, Helena; Bathen, Tone F

    2018-05-01

    The objective of this study was to investigate whether quantitative imaging features derived from combined 18 F-fluciclovine PET/multiparametric MRI show potential for detection and characterization of primary prostate cancer. Methods: Twenty-eight patients diagnosed with high-risk prostate cancer underwent simultaneous 18 F-fluciclovine PET/MRI before radical prostatectomy. Volumes of interest (VOIs) for prostate tumors, benign prostatic hyperplasia (BPH) nodules, prostatitis, and healthy tissue were delineated on T2-weighted images, using histology as a reference. Tumor VOIs were marked as high-grade (≥Gleason grade group 3) or not. MRI and PET features were extracted on the voxel and VOI levels. Partial least-squared discriminant analysis (PLS-DA) with double leave-one-patient-out cross-validation was performed to distinguish tumors from benign tissue (BPH, prostatitis, or healthy tissue) and high-grade tumors from other tissue (low-grade tumors or benign tissue). The performance levels of PET, MRI, and combined PET/MRI features were compared using the area under the receiver-operating-characteristic curve (AUC). Results: Voxel and VOI features were extracted from 40 tumor VOIs (26 high-grade), 36 BPH VOIs, 6 prostatitis VOIs, and 37 healthy-tissue VOIs. PET/MRI performed better than MRI and PET alone for distinguishing tumors from benign tissue (AUCs of 87%, 81%, and 83%, respectively, at the voxel level and 96%, 93%, and 93%, respectively, at the VOI level) and high-grade tumors from other tissue (AUCs of 85%, 79%, and 81%, respectively, at the voxel level and 93%, 93%, and 91%, respectively, at the VOI level). T2-weighted MRI, diffusion-weighted MRI, and PET features were the most important for classification. Conclusion: Combined 18 F-fluciclovine PET/multiparametric MRI shows potential for improving detection and characterization of high-risk prostate cancer, in comparison to MRI and PET alone. © 2018 by the Society of Nuclear Medicine and Molecular

  1. Genome sequence of Lactobacillus salivarius SMXD51, a potential probiotic strain isolated from chicken cecum, showing anti-campylobacter activity.

    Science.gov (United States)

    Kergourlay, Gilles; Messaoudi, Soumaya; Dousset, Xavier; Prévost, Hervé

    2012-06-01

    We report the draft genome sequence of Lactobacillus salivarius SMXD51, isolated from the cecum of healthy chickens showing an activity against Campylobacter--the food-borne pathogen that is the most common cause of gastroenteritis in the European Union (EU)--and potentially interesting features for a probiotic strain, explaining our interest in it.

  2. New method for evaluating liquefaction potential

    Energy Technology Data Exchange (ETDEWEB)

    Arulmoli, K.; Arulanandan, K.; Seed, H.B.

    1985-01-01

    A new method of indexing the grain and aggregate properties of sand using electrical parameters is described. Correlations are established between these parameters and relative density, D /sub r/ , cyclic stress ratio, /tau//sigma'/sub 0/, and K2 /sub max/ . An electrical probe, used to predict these parameters from in-situ electrical measurements, is described. Evaluations are made of D /sub r/ and /tau//sigma/sub 0/, which are compared with values measured independently from controlled laboratory tests. Reasonable agreement is found between predicted and measured values. The potential applicability of the electrical probe in the field is shown by evaluation of liquefaction and nonliquefaction at sites affected by the 1906 San Francisco, Niigata and Tangshan earthquakes.

  3. Complex mixtures of dissolved pesticides show potential aquatic toxicity in a synoptic study of Midwestern U.S. streams

    Science.gov (United States)

    Nowell, Lisa H.; Moran, Patrick W.; Schmidt, Travis S.; Norman, Julia E.; Nakagaki, Naomi; Shoda, Megan E.; Mahler, Barbara J.; Van Metre, Peter C.; Stone, Wesley W.; Sandstrom, Mark W.; Hladik, Michelle L.

    2018-01-01

    Aquatic organisms in streams are exposed to pesticide mixtures that vary in composition over time in response to changes in flow conditions, pesticide inputs to the stream, and pesticide fate and degradation within the stream. To characterize mixtures of dissolved-phase pesticides and degradates in Midwestern streams, a synoptic study was conducted at 100 streams during May–August 2013. In weekly water samples, 94 pesticides and 89 degradates were detected, with a median of 25 compounds detected per sample and 54 detected per site. In a screening-level assessment using aquatic-life benchmarks and the Pesticide Toxicity Index (PTI), potential effects on fish were unlikely in most streams. For invertebrates, potential chronic toxicity was predicted in 53% of streams, punctuated in 12% of streams by acutely toxic exposures. For aquatic plants, acute but likely reversible effects on biomass were predicted in 75% of streams, with potential longer-term effects on plant communities in 9% of streams. Relatively few pesticides in water—atrazine, acetochlor, metolachlor, imidacloprid, fipronil, organophosphate insecticides, and carbendazim—were predicted to be major contributors to potential toxicity. Agricultural streams had the highest potential for effects on plants, especially in May–June, corresponding to high spring-flush herbicide concentrations. Urban streams had higher detection frequencies and concentrations of insecticides and most fungicides than in agricultural streams, and higher potential for invertebrate toxicity, which peaked during July–August. Toxicity-screening predictions for invertebrates were supported by quantile regressions showing significant associations for the Benthic Invertebrate-PTI and imidacloprid concentrations with invertebrate community metrics for MSQA streams, and by mesocosm toxicity testing with imidacloprid showing effects on invertebrate communities at environmentally relevant concentrations. This study documents the most

  4. From the Kirsch-Kress potential method via the range test to the singular sources method

    International Nuclear Information System (INIS)

    Potthast, R; Schulz, J

    2005-01-01

    We review three reconstruction methods for inverse obstacle scattering problems. We will analyse the relation between the Kirsch-Kress potential method 1986, the range test of Kusiak, Potthast and Sylvester (2003) and the singular sources method of Potthast (2000). In particular, we show that the range test is a logical extension of the Kirsch-Kress method into the category of sampling methods employing the tool of domain sampling. Then we will show how a multi-wave version of the range test can be set up and we will work out its relation to the singular sources method. Numerical examples and demonstrations will be provided

  5. Methods to preserve potentially toxigenic fungi

    Directory of Open Access Journals (Sweden)

    Lucas Costa Guimarães

    2014-01-01

    Full Text Available Microorganisms are a source of many high-value compounds which are useful to every living being, such as humans, plants and animals. Since the process of isolating and improving a microorganism can be lengthy and expensive, preserving the obtained characteristic is of paramount importance, so the process does not need to be repeated. Fungi are eukaryotic, achlorophyllous, heterotrophic organisms, usually filamentous, absorb their food, can be either macro or microscopic, propagate themselves by means of spores and store glycogen as a source of storage. Fungi, while infesting food, may produce toxic substances such as mycotoxins. The great genetic diversity of the Kingdom Fungi renders the preservation of fungal cultures for many years relevant. Several international reference mycological culture collections are maintained in many countries. The methodologies that are most fit for preserving microorganisms for extended periods are based on lowering the metabolism until it reaches a stage of artificial dormancy . The goal of this study was to analyze three methods for potentially toxigenic fungal conservation (Castellani's, continuous subculture and lyophilization and to identify the best among them.

  6. A regularization method for extrapolation of solar potential magnetic fields

    Science.gov (United States)

    Gary, G. A.; Musielak, Z. E.

    1992-01-01

    The mathematical basis of a Tikhonov regularization method for extrapolating the chromospheric-coronal magnetic field using photospheric vector magnetograms is discussed. The basic techniques show that the Cauchy initial value problem can be formulated for potential magnetic fields. The potential field analysis considers a set of linear, elliptic partial differential equations. It is found that, by introducing an appropriate smoothing of the initial data of the Cauchy potential problem, an approximate Fourier integral solution is found, and an upper bound to the error in the solution is derived. This specific regularization technique, which is a function of magnetograph measurement sensitivities, provides a method to extrapolate the potential magnetic field above an active region into the chromosphere and low corona.

  7. Dysfunctional methods and the effective potential

    International Nuclear Information System (INIS)

    Dannenberg, A.; California Univ., Berkeley

    1988-01-01

    The effective potential is a useful and much-studied object. It is known to be both real and convex, but a perturbative calculation often gives a complex and nonconvex result. In this letter we address the apparent conflict between perturbation theory and the convexity of the effective potential. (orig.)

  8. Bacteria Associated to Plants Naturally Selected in a Historical PCB Polluted Soil Show Potential to Sustain Natural Attenuation.

    Science.gov (United States)

    Vergani, Lorenzo; Mapelli, Francesca; Marasco, Ramona; Crotti, Elena; Fusi, Marco; Di Guardo, Antonio; Armiraglio, Stefano; Daffonchio, Daniele; Borin, Sara

    2017-01-01

    The exploitation of the association between plants and microorganisms is a promising approach able to boost natural attenuation processes for soil clean-up in vast polluted areas characterized by mixed chemical contamination. We aimed to explore the selection of root-associated bacterial communities driven by different plant species spontaneously established in abandoned agricultural soils within a historical polluted site in north Italy. The site is highly contaminated by chlorinated persistent organic pollutants, mainly constituted by polychlorobiphenyls (PCBs), together with heavy metals and metalloids, in variable concentrations and uneven distribution. The overall structure of the non-vegetated and root-associated soil fractions bacterial communities was described by high-throughput sequencing of the 16S rRNA gene, and a collection of 165 rhizobacterial isolates able to use biphenyl as unique carbon source was assayed for plant growth promotion (PGP) traits and bioremediation potential. The results showed that the recruitment of specific bacterial communities in the root-associated soil fractions was driven by both soil fractions and plant species, explaining 21 and 18% of the total bacterial microbiome variation, respectively. PCR-based detection in the soil metagenome of bacterial bphA gene, encoding for the biphenyl dioxygenase α subunit, indicated that the soil in the site possesses metabolic traits linked to PCB degradation. Biphenyl-utilizing bacteria isolated from the rhizosphere of the three different plant species showed low phylogenetic diversity and well represented functional traits, in terms of PGP and bioremediation potential. On average, 72% of the strains harbored the bphA gene and/or displayed catechol 2,3-dioxygenase activity, involved in aromatic ring cleavage. PGP traits, including 1-aminocyclopropane-1-carboxylic acid deaminase activity potentially associated to plant stress tolerance induction, were widely distributed among the isolates

  9. Bacteria Associated to Plants Naturally Selected in a Historical PCB Polluted Soil Show Potential to Sustain Natural Attenuation

    KAUST Repository

    Vergani, Lorenzo

    2017-07-25

    The exploitation of the association between plants and microorganisms is a promising approach able to boost natural attenuation processes for soil clean-up in vast polluted areas characterized by mixed chemical contamination. We aimed to explore the selection of root-associated bacterial communities driven by different plant species spontaneously established in abandoned agricultural soils within a historical polluted site in north Italy. The site is highly contaminated by chlorinated persistent organic pollutants, mainly constituted by polychlorobiphenyls (PCBs), together with heavy metals and metalloids, in variable concentrations and uneven distribution. The overall structure of the non-vegetated and root-associated soil fractions bacterial communities was described by high-throughput sequencing of the 16S rRNA gene, and a collection of 165 rhizobacterial isolates able to use biphenyl as unique carbon source was assayed for plant growth promotion (PGP) traits and bioremediation potential. The results showed that the recruitment of specific bacterial communities in the root-associated soil fractions was driven by both soil fractions and plant species, explaining 21 and 18% of the total bacterial microbiome variation, respectively. PCR-based detection in the soil metagenome of bacterial bphA gene, encoding for the biphenyl dioxygenase α subunit, indicated that the soil in the site possesses metabolic traits linked to PCB degradation. Biphenyl-utilizing bacteria isolated from the rhizosphere of the three different plant species showed low phylogenetic diversity and well represented functional traits, in terms of PGP and bioremediation potential. On average, 72% of the strains harbored the bphA gene and/or displayed catechol 2,3-dioxygenase activity, involved in aromatic ring cleavage. PGP traits, including 1-aminocyclopropane-1-carboxylic acid deaminase activity potentially associated to plant stress tolerance induction, were widely distributed among the isolates

  10. Bacteria Associated to Plants Naturally Selected in a Historical PCB Polluted Soil Show Potential to Sustain Natural Attenuation

    Directory of Open Access Journals (Sweden)

    Lorenzo Vergani

    2017-07-01

    Full Text Available The exploitation of the association between plants and microorganisms is a promising approach able to boost natural attenuation processes for soil clean-up in vast polluted areas characterized by mixed chemical contamination. We aimed to explore the selection of root-associated bacterial communities driven by different plant species spontaneously established in abandoned agricultural soils within a historical polluted site in north Italy. The site is highly contaminated by chlorinated persistent organic pollutants, mainly constituted by polychlorobiphenyls (PCBs, together with heavy metals and metalloids, in variable concentrations and uneven distribution. The overall structure of the non-vegetated and root-associated soil fractions bacterial communities was described by high-throughput sequencing of the 16S rRNA gene, and a collection of 165 rhizobacterial isolates able to use biphenyl as unique carbon source was assayed for plant growth promotion (PGP traits and bioremediation potential. The results showed that the recruitment of specific bacterial communities in the root-associated soil fractions was driven by both soil fractions and plant species, explaining 21 and 18% of the total bacterial microbiome variation, respectively. PCR-based detection in the soil metagenome of bacterial bphA gene, encoding for the biphenyl dioxygenase α subunit, indicated that the soil in the site possesses metabolic traits linked to PCB degradation. Biphenyl-utilizing bacteria isolated from the rhizosphere of the three different plant species showed low phylogenetic diversity and well represented functional traits, in terms of PGP and bioremediation potential. On average, 72% of the strains harbored the bphA gene and/or displayed catechol 2,3-dioxygenase activity, involved in aromatic ring cleavage. PGP traits, including 1-aminocyclopropane-1-carboxylic acid deaminase activity potentially associated to plant stress tolerance induction, were widely distributed

  11. Video monitoring of brown planthopper predation in rice shows flaws of sentinel methods

    NARCIS (Netherlands)

    Zou, Yi; Kraker, De Joop; Bianchi, Felix J.J.A.; Telgen, Van Mario D.; Xiao, Haijun; Werf, Van Der Wopke

    2017-01-01

    Immobilized preys are routinely used in agro-ecological exposure studies to quantify predation of pests under field conditions, but this method has not been validated. Our purpose was to determine the validity of using immobilized adults of the major rice pest Nilaparvata lugens, brown plant hopper

  12. Exploration of a Method to Assess Children's Understandings of a Phenomenon after Viewing a Demonstration Show

    Science.gov (United States)

    DeKorver, Brittland K.; Choi, Mark; Towns, Marcy

    2017-01-01

    Chemical demonstration shows are a popular form of informal science education (ISE), employed by schools, museums, and other institutions in order to improve the public's understanding of science. Just as teachers employ formative and summative assessments in the science classroom to evaluate the impacts of their efforts, it is important to assess…

  13. Exactness of supersymmetric WKB method for translational shape invariant potentials

    International Nuclear Information System (INIS)

    Cheng, K M; Leung, P T; Pang, C S

    2003-01-01

    By examining the generic form of the superpotential of translational shape invariant potentials (TSIPs), we explicitly show the exactness of the lowest order supersymmetric WKB (SWKB) formula for TSIPs. Remarkably, our method applies to both unbroken and broken supersymmetric systems. We also demonstrate the equivalence of one-parameter and multi-parameter TSIPs, thus establishing the exactness of the SWKB formula for all TSIPs

  14. Exactness of supersymmetric WKB method for translational shape invariant potentials

    CERN Document Server

    Cheng, K M; Pang, C S

    2003-01-01

    By examining the generic form of the superpotential of translational shape invariant potentials (TSIPs), we explicitly show the exactness of the lowest order supersymmetric WKB (SWKB) formula for TSIPs. Remarkably, our method applies to both unbroken and broken supersymmetric systems. We also demonstrate the equivalence of one-parameter and multi-parameter TSIPs, thus establishing the exactness of the SWKB formula for all TSIPs.

  15. Application of potential harmonic expansion method to BEC ...

    Indian Academy of Sciences (India)

    We adopt the potential harmonics expansion method for an ab initio solu- ... commonly adopted mean-field theories, our method is capable of handling ..... potentials in self-consistent mean-field calculation [7] gives wrong results as the.

  16. Methods for determination of biomethane potential of feedstocks: a review

    Directory of Open Access Journals (Sweden)

    Raphael Muzondiwa Jingura

    2017-06-01

    Full Text Available Biogas produced during anaerobic digestion (AD of biodegradable organic materials. AD is a series of biochemical reactions in which microorganisms degrade organic matter under anaerobic conditions. There are many biomass resources that can be degraded by AD to produce biogas. Biogas consists of methane, carbon dioxide, and trace amounts of other gases. The gamut of feedstocks used in AD includes animal manure, municipal solid waste, sewage sludge, and various crops. Several factors affect the potential of feedstocks for biomethane production. The factors include nutrient content, total and volatile solids (VS content, chemical and biological oxygen demand, carbon/nitrogen ratio, and presence of inhibitory substances. The biochemical methane potential (BMP, often defined as the maximum volume of methane produced per g of VS substrate provides an indication of the biodegradability of a substrate and its potential to produce methane via AD. The BMP test is a method of establishing a baseline for performance of AD. BMP data are useful for designing AD parameters in order to optimise methane production. Several methods which include experimental and theoretical methods can be used to determine BMP. The objective of this paper is to review several methods with a special focus on their advantages and disadvantages. The review shows that experimental methods, mainly the BMP test are widely used. The BMP test is credited for its reliability and validity. There are variants of BMP assays as well. Theoretical models are alternative methods to estimate BMP. They are credited for being fast and easy to use. Spectroscopy has emerged as a new experimental tool to determine BMP. Each method has its own advantages and disadvantages with reference to efficacy, time, and ease of use. Choosing a method to use depends on various exigencies. More work needs to be continuously done in order to improve the various methods used to determine BMP.

  17. A simple method for generating exactly solvable quantum mechanical potentials

    CERN Document Server

    Williams, B W

    1993-01-01

    A simple transformation method permitting the generation of exactly solvable quantum mechanical potentials from special functions solving second-order differential equations is reviewed. This method is applied to Gegenbauer polynomials to generate an attractive radial potential. The relationship of this method to the determination of supersymmetric quantum mechanical superpotentials is discussed, and the superpotential for the radial potential is also derived. (author)

  18. Effective core potential methods for the lanthanides

    International Nuclear Information System (INIS)

    Cundari, T.R.; Stevens, W.J.

    1993-01-01

    In this paper a complete set of effective core potentials (ECPs) and valence basis sets for the lanthanides (Ce to Lu) are derived. These ECPs are consistent not only within the lanthanide series, but also with the third-row transition metals which bracket them. A 46-electron core was chosen to provide the best compromise between computational savings and chemical accuracy. Thus, the 5s and 5p are included as ''outer'' core while all lower energy atomic orbitals (AOs) are replaced with the ECP. Generator states were chosen from the most chemically relevant +3 and +2 oxidation states. The results of atomic calculations indicate that the greatest error vs highly accurate numerical potential/large, even-tempered basis set calculations results from replacement of the large, even-tempered basis sets with more compact representations. However, the agreement among atomic calculations remains excellent with both basis set sizes, for a variety of spin and oxidation states, with a significant savings in time for the optimized valence basis set. It is expected that the compact representation of the ECPs and valence basis sets will eventually encourage their use by computational chemists to further explore the bonding and reactivity of lanthanide complexes

  19. Constrained potential method for false vacuum decays

    International Nuclear Information System (INIS)

    Park, Jae-hyeon

    2010-11-01

    A procedure is reported for numerical analysis of false vacuum transition in a model with multiple scalar fields. It is a refined version of the approach by Konstandin and Huber. The alteration makes it possible to tackle a class of problems that was difficult or unsolvable with the original method, i.e. those with a distant or nonexistent true vacuum. An example with an unbounded-from-below direction is presented. (orig.)

  20. Solution of Dirac equation for Eckart potential and trigonometric Manning Rosen potential using asymptotic iteration method

    International Nuclear Information System (INIS)

    Arum Sari, Resita; Suparmi, A; Cari, C

    2016-01-01

    The Dirac equation for Eckart potential and trigonometric Manning Rosen potential with exact spin symmetry is obtained using an asymptotic iteration method. The combination of the two potentials is substituted into the Dirac equation, then the variables are separated into radial and angular parts. The Dirac equation is solved by using an asymptotic iteration method that can reduce the second order differential equation into a differential equation with substitution variables of hypergeometry type. The relativistic energy is calculated using Matlab 2011. This study is limited to the case of spin symmetry. With the asymptotic iteration method, the energy spectra of the relativistic equations and equations of orbital quantum number l can be obtained, where both are interrelated between quantum numbers. The energy spectrum is also numerically solved using the Matlab software, where the increase in the radial quantum number n r causes the energy to decrease. The radial part and the angular part of the wave function are defined as hypergeometry functions and visualized with Matlab 2011. The results show that the disturbance of a combination of the Eckart potential and trigonometric Manning Rosen potential can change the radial part and the angular part of the wave function. (paper)

  1. Endometrial Cancer Side-Population Cells Show Prominent Migration and Have a Potential to Differentiate into the Mesenchymal Cell Lineage

    Science.gov (United States)

    Kato, Kiyoko; Takao, Tomoka; Kuboyama, Ayumi; Tanaka, Yoshihiro; Ohgami, Tatsuhiro; Yamaguchi, Shinichiro; Adachi, Sawako; Yoneda, Tomoko; Ueoka, Yousuke; Kato, Keiji; Hayashi, Shinichi; Asanoma, Kazuo; Wake, Norio

    2010-01-01

    Cancer stem-like cell subpopulations, referred to as “side-population” (SP) cells, have been identified in several tumors based on their ability to efflux the fluorescent dye Hoechst 33342. Although SP cells have been identified in the normal human endometrium and endometrial cancer, little is known about their characteristics. In this study, we isolated and characterized the SP cells in human endometrial cancer cells and in rat endometrial cells expressing oncogenic human K-Ras protein. These SP cells showed i) reduction in the expression levels of differentiation markers; ii) long-term proliferative capacity of the cell cultures; iii) self-renewal capacity in vitro; iv) enhancement of migration, lamellipodia, and, uropodia formation; and v) enhanced tumorigenicity. In nude mice, SP cells formed large, invasive tumors, which were composed of both tumor cells and stromal-like cells with enriched extracellular matrix. The expression levels of vimentin, α-smooth muscle actin, and collagen III were enhanced in SP tumors compared with the levels in non-SP tumors. In addition, analysis of microdissected samples and fluorescence in situ hybridization of Hec1-SP-tumors showed that the stromal-like cells with enriched extracellular matrix contained human DNA, confirming that the stromal-like cells were derived from the inoculated cells. Moreober, in a Matrigel assay, SP cells differentiated into α-smooth muscle actin-expressing cells. These findings demonstrate that SP cells have cancer stem-like cell features, including the potential to differentiate into the mesenchymal cell lineage. PMID:20008133

  2. A xylanase gene directly cloned from the genomic DNA of alkaline wastewater sludge showing application potential in the paper industry.

    Science.gov (United States)

    Zhao, Yanyu; Luo, Huiying; Meng, Kun; Shi, Pengjun; Wang, Guozeng; Yang, Peilong; Yuan, Tiezheng; Yao, Bin

    2011-09-01

    A xylanase gene, aws-2x, was directly cloned from the genomic DNA of the alkaline wastewater sludge using degenerated PCR and modified TAIL-PCR. The deduced amino acid sequence of AWS-2x shared the highest identity (60%) with the xylanase from Chryseobacterium gleum belonging to the glycosyl hydrolase GH family 10. Recombinant AWS-2x was expressed in Escherichia coli BL21 (DE3) and purified to electrophoretic homogeneity. The enzyme showed maximal activity at pH 7.5 and 55 °C, maintained more than 50% of maximal activity when assayed at pH 9.0, and was stable over a wide pH range from 4.0 to 11.0. The specific activity of AWS-2x towards hardwood xylan (beechwood and birchwood xylan) was significantly higher than that to cereal xylan (oat spelt xylan and wheat arabinoxylan). These properties make AWS-2x a potential candidate for application in the pulp and paper industry.

  3. Bayesian methods to estimate urban growth potential

    Science.gov (United States)

    Smith, Jordan W.; Smart, Lindsey S.; Dorning, Monica; Dupéy, Lauren Nicole; Méley, Andréanne; Meentemeyer, Ross K.

    2017-01-01

    Urban growth often influences the production of ecosystem services. The impacts of urbanization on landscapes can subsequently affect landowners’ perceptions, values and decisions regarding their land. Within land-use and land-change research, very few models of dynamic landscape-scale processes like urbanization incorporate empirically-grounded landowner decision-making processes. Very little attention has focused on the heterogeneous decision-making processes that aggregate to influence broader-scale patterns of urbanization. We examine the land-use tradeoffs faced by individual landowners in one of the United States’ most rapidly urbanizing regions − the urban area surrounding Charlotte, North Carolina. We focus on the land-use decisions of non-industrial private forest owners located across the region’s development gradient. A discrete choice experiment is used to determine the critical factors influencing individual forest owners’ intent to sell their undeveloped properties across a series of experimentally varied scenarios of urban growth. Data are analyzed using a hierarchical Bayesian approach. The estimates derived from the survey data are used to modify a spatially-explicit trend-based urban development potential model, derived from remotely-sensed imagery and observed changes in the region’s socioeconomic and infrastructural characteristics between 2000 and 2011. This modeling approach combines the theoretical underpinnings of behavioral economics with spatiotemporal data describing a region’s historical development patterns. By integrating empirical social preference data into spatially-explicit urban growth models, we begin to more realistically capture processes as well as patterns that drive the location, magnitude and rates of urban growth.

  4. Niche tracking and rapid establishment of distributional equilibrium in the house sparrow show potential responsiveness of species to climate change.

    Directory of Open Access Journals (Sweden)

    William B Monahan

    Full Text Available The ability of species to respond to novel future climates is determined in part by their physiological capacity to tolerate climate change and the degree to which they have reached and continue to maintain distributional equilibrium with the environment. While broad-scale correlative climatic measurements of a species' niche are often described as estimating the fundamental niche, it is unclear how well these occupied portions actually approximate the fundamental niche per se, versus the fundamental niche that exists in environmental space, and what fitness values bounding the niche are necessary to maintain distributional equilibrium. Here, we investigate these questions by comparing physiological and correlative estimates of the thermal niche in the introduced North American house sparrow (Passer domesticus. Our results indicate that occupied portions of the fundamental niche derived from temperature correlations closely approximate the centroid of the existing fundamental niche calculated on a fitness threshold of 50% population mortality. Using these niche measures, a 75-year time series analysis (1930-2004 further shows that: (i existing fundamental and occupied niche centroids did not undergo directional change, (ii interannual changes in the two niche centroids were correlated, (iii temperatures in North America moved through niche space in a net centripetal fashion, and consequently, (iv most areas throughout the range of the house sparrow tracked the existing fundamental niche centroid with respect to at least one temperature gradient. Following introduction to a new continent, the house sparrow rapidly tracked its thermal niche and established continent-wide distributional equilibrium with respect to major temperature gradients. These dynamics were mediated in large part by the species' broad thermal physiological tolerances, high dispersal potential, competitive advantage in human-dominated landscapes, and climatically induced

  5. Baryon interactions in lattice QCD: the direct method vs. the HAL QCD potential method

    Science.gov (United States)

    Iritani, T.; HAL QCD Collaboration

    We make a detailed comparison between the direct method and the HAL QCD potential method for the baryon-baryon interactions, taking the $\\Xi\\Xi$ system at $m_\\pi= 0.51$ GeV in 2+1 flavor QCD and using both smeared and wall quark sources. The energy shift $\\Delta E_\\mathrm{eff}(t)$ in the direct method shows the strong dependence on the choice of quark source operators, which means that the results with either (or both) source are false. The time-dependent HAL QCD method, on the other hand, gives the quark source independent $\\Xi\\Xi$ potential, thanks to the derivative expansion of the potential, which absorbs the source dependence to the next leading order correction. The HAL QCD potential predicts the absence of the bound state in the $\\Xi\\Xi$($^1$S$_0$) channel at $m_\\pi= 0.51$ GeV, which is also confirmed by the volume dependence of finite volume energy from the potential. We also demonstrate that the origin of the fake plateau in the effective energy shift $\\Delta E_\\mathrm{eff}(t)$ at $t \\sim 1$ fm can be clarified by a few low-lying eigenfunctions and eigenvalues on the finite volume derived from the HAL QCD potential, which implies that the ground state saturation of $\\Xi\\Xi$($^1$S$_0$) requires $t \\sim 10$ fm in the direct method for the smeared source on $(4.3 \\ \\mathrm{fm})^3$ lattice, while the HAL QCD method does not suffer from such a problem.

  6. Recruitment Methods and Show Rates to a Prostate Cancer Early Detection Program for High-Risk Men: A Comprehensive Analysis

    Science.gov (United States)

    Giri, Veda N.; Coups, Elliot J.; Ruth, Karen; Goplerud, Julia; Raysor, Susan; Kim, Taylor Y.; Bagden, Loretta; Mastalski, Kathleen; Zakrzewski, Debra; Leimkuhler, Suzanne; Watkins-Bruner, Deborah

    2009-01-01

    Purpose Men with a family history (FH) of prostate cancer (PCA) and African American (AA) men are at higher risk for PCA. Recruitment and retention of these high-risk men into early detection programs has been challenging. We report a comprehensive analysis on recruitment methods, show rates, and participant factors from the Prostate Cancer Risk Assessment Program (PRAP), which is a prospective, longitudinal PCA screening study. Materials and Methods Men 35–69 years are eligible if they have a FH of PCA, are AA, or have a BRCA1/2 mutation. Recruitment methods were analyzed with respect to participant demographics and show to the first PRAP appointment using standard statistical methods Results Out of 707 men recruited, 64.9% showed to the initial PRAP appointment. More individuals were recruited via radio than from referral or other methods (χ2 = 298.13, p < .0001). Men recruited via radio were more likely to be AA (p<0.001), less educated (p=0.003), not married or partnered (p=0.007), and have no FH of PCA (p<0.001). Men recruited via referrals had higher incomes (p=0.007). Men recruited via referral were more likely to attend their initial PRAP visit than those recruited by radio or other methods (χ2 = 27.08, p < .0001). Conclusions This comprehensive analysis finds that radio leads to higher recruitment of AA men with lower socioeconomic status. However, these are the high-risk men that have lower show rates for PCA screening. Targeted motivational measures need to be studied to improve show rates for PCA risk assessment for these high-risk men. PMID:19758657

  7. Towards a Kohn-Sham potential via the optimized effective-potential method

    International Nuclear Information System (INIS)

    Norman, M.R.; Koelling, D.D.

    1984-01-01

    The optimized effective-potential (OEP) method is applied to a self-interaction-corrected local-spin-density (SIC-LSD) energy functional. The local potential which results has the useful properties of being both self-interaction free and orbital independent, and it can thus be regarded as a good approximation to the exact Kohn-Sham potential. A number of atomic systems are examined in the exchange-only and in the Ceperley-Alder exchange-correlation approximations. The resulting total energies are very close to those obtained by previous applications of the LSD-SIC functional. The resultant potentials are structurally similar to those derived by applying the OEP method to a Hartree-Fock Hamiltonian: showing much improved behavior over the local-spin-density approximation in both large- and small-r regions as well as the characteristic intershell cusplike structure. The eigenvalues have less formal significance than the more standard approaches, especially those for unoccupied orbitals which seem to have no significance whatsoever. Nonetheless, the highest occupied eigenvalue agrees closely with the conventional LSD-SIC value. However, for the deeper levels, each eigenvalue lies higher than the comparable eigenvalue of the conventional SIC, although lower than the eigenvalue of the LSD potential: the deeper the level, the larger the difference. This property follows from the nonvariational character of the eigenvalues, and it is shown that one can obtain realistic excitation spectra from this formalism by utilizing the appropriate variational quantity. The results obtained illustrate some of the less understood issues in the application of the Kohn-Sham procedure within density-functional theory

  8. An analysis of pipe degradation shape using potential drop method

    International Nuclear Information System (INIS)

    Jegal, S.; Lee, S. H.

    1999-01-01

    The Potential Drop (PD) method, one of NDE (Non-Destructive Evaluation) method is used to analyze the thickness distribution of pipes degraded by FAC (Flow Accelerated Corrosion). A DCPD (Direct Current Potential Drop) system which can measure PD for direct current was made, and the specimens with line defects and cylinder type defects have been used for experiments to prove the theory of Potential Drop method and to find out the effects of each factors. The experiment to find out defect distributions has been performed and it is found that PD method can analyze almost correct position of defects

  9. Early and delayed cardioprotective intervention with dexrazoxane each show different potential for prevention of chronic anthracycline cardiotoxicity in rabbits

    International Nuclear Information System (INIS)

    Jirkovský, Eduard; Lenčová-Popelová, Olga; Hroch, Miloš; Adamcová, Michaela; Mazurová, Yvona; Vávrová, Jaroslava

    2013-01-01

    Despite incomplete understanding to its mechanism of action, dexrazoxane (DEX) is still the only clearly effective cardioprotectant against chronic anthracycline (ANT) cardiotoxicity. However, its clinical use is currently restricted to patients exceeding significant ANT cumulative dose (300 mg/m 2 ), although each ANT cycle may induce certain potentially irreversible myocardial damage. Therefore, the aim of this study was to compare early and delayed DEX intervention against chronic ANT cardiotoxicity and study the molecular events involved. The cardiotoxicity was induced in rabbits with daunorubicin (DAU; 3 mg/kg/week for 10 weeks); DEX (60 mg/kg) was administered either before the 1st or 7th DAU dose (i.e. after ≈300 mg/m 2 cumulative dose). While both DEX administration schedules prevented DAU-induced premature deaths and severe congestive heart failure, only the early intervention completely prevented the left ventricular dysfunction, myocardial morphological changes and mitochondrial damage. Further molecular analyses did not support the assumption that DEX cardioprotection is based and directly proportional to protection from DAU-induced oxidative damage and/or deletions in mtDNA. Nevertheless, DAU induced significant up-regulation of heme oxygenase 1 pathway while heme synthesis was inversely regulated and both changes were schedule-of-administration preventable by DEX. Early and delayed DEX interventions also differed in ability to prevent DAU-induced down-regulation of expression of mitochondrial proteins encoded by both nuclear and mitochondrial genome. Hence, the present functional, morphological as well as the molecular data highlights the enormous cardioprotective effects of DEX and provides novel insights into the molecular events involved. Furthermore, the data suggests that currently recommended delayed intervention may not be able to take advantage of the full cardioprotective potential of the drug

  10. LEAKAGE CHARACTERISTICS OF BASE OF RIVERBANK BY SELF POTENTIAL METHOD AND EXAMINATION OF EFFECTIVENESS OF SELF POTENTIAL METHOD TO HEALTH MONITORING OF BASE OF RIVERBANK

    Science.gov (United States)

    Matsumoto, Kensaku; Okada, Takashi; Takeuchi, Atsuo; Yazawa, Masato; Uchibori, Sumio; Shimizu, Yoshihiko

    Field Measurement of Self Potential Method using Copper Sulfate Electrode was performed in base of riverbank in WATARASE River, where has leakage problem to examine leakage characteristics. Measurement results showed typical S-shape what indicates existence of flow groundwater. The results agreed with measurement results by Ministry of Land, Infrastructure and Transport with good accuracy. Results of 1m depth ground temperature detection and Chain-Array detection showed good agreement with results of the Self Potential Method. Correlation between Self Potential value and groundwater velocity was examined model experiment. The result showed apparent correlation. These results indicate that the Self Potential Method was effective method to examine the characteristics of ground water of base of riverbank in leakage problem.

  11. Designing and overproducing a tandem epitope of gp350/220 that shows a potential to become an EBV vaccine

    Directory of Open Access Journals (Sweden)

    Widodo

    2018-03-01

    Full Text Available Background: Epstein-Barr virus (EBV can cause cancer in people from around the world. There is no EBV vaccine available for use on a global scale. However, emerging evidence suggests that the epitope on the gp350/220 capsid protein may be developed into an EBV vaccine. Nevertheless, the production of small, single epitope is challenging of stability issues and possible alteration of peptide structure. In this study, a tandem epitope was developed consisting of three single epitopes, aimed to improve stability, antigenicity and preserve epitope structure. Materials and methods: A tandem epitope was designed using bioinformatics based on the epitope structure of the gp350/220 protein. The tandem epitope structure was analyzed using a protein folding method with Abalone software, which was further refined via YASARA force field and molecular repairing using a FoldX method. Immunogenicity was examined with Epitopia software, whereas allergen properties were tested using AlgPred. The pattern of the tandem epitope binding with anti-gp350/220 antibodies was performed using Z-dock and snugDock. The tandem epitope was then overproduced in E. coli strain BL21 as a host cell. Result: Our model demonstrated a successfully designed and overproduced tandem epitope. The tandem epitope demonstrated a similar structure compared with the epitope of whole protein gp350/220. Our epitope also demonstrated non-allergen and antigenicity properties, and possessed antibody binding patterns consistent with whole protein gp350/220. Conclusion and recommendation: These data suggest a novel tandem epitope composed of three similar epitopes demonstrates antigenicity, structure, and binding properties consistent with whole protein gp350/220. We also demonstrate successful production of the tandem epitope using E. coli strain BL21 as a host. Future in vivo experimental animal research is necessary to test the ability of this tandem epitope to stimulate antibody production

  12. Characterization of Fetal Keratinocytes, Showing Enhanced Stem Cell-Like Properties: A Potential Source of Cells for Skin Reconstruction

    Directory of Open Access Journals (Sweden)

    Kenneth K.B. Tan

    2014-08-01

    Full Text Available Epidermal stem cells have been in clinical application as a source of culture-generated grafts. Although applications for such cells are increasing due to aging populations and the greater incidence of diabetes, current keratinocyte grafting technology is limited by immunological barriers and the time needed for culture amplification. We studied the feasibility of using human fetal skin cells for allogeneic transplantation and showed that fetal keratinocytes have faster expansion times, longer telomeres, lower immunogenicity indicators, and greater clonogenicity with more stem cell indicators than adult keratinocytes. The fetal cells did not induce proliferation of T cells in coculture and were able to suppress the proliferation of stimulated T cells. Nevertheless, fetal keratinocytes could stratify normally in vitro. Experimental transplantation of fetal keratinocytes in vivo seeded on an engineered plasma scaffold yielded a well-stratified epidermal architecture and showed stable skin regeneration. These results support the possibility of using fetal skin cells for cell-based therapeutic grafting.

  13. Impacts of tourism hotspots on vegetation communities show a higher potential for self-propagation along roads than hiking trails.

    Science.gov (United States)

    Wolf, Isabelle D; Croft, David B

    2014-10-01

    Vegetation communities along recreational tracks may suffer from substantial edge-effects through the impacts of trampling, modified environmental conditions and competition with species that benefit from disturbance. We assessed impacts on trackside vegetation by comparing high and low usage tourism sites at a 1-10 m distance from recreational tracks in a popular arid-lands tourism destination in South Australia. The central aim was quantification of the strengths and spatial extent of tourism impacts along recreational tracks with a qualitative comparison of roads and trails. Track-distance gradients were most prevalent at high usage sites. There, species community composition was altered, total plant cover decreased, non-native species cover increased, plant diversity increased or decreased (depending on the distance) and soil compaction increased towards recreational tracks. Roadside effects were greater and more pervasive than trailside effects. Further, plant diversity did not continuously increase towards the road verge as it did along trails but dropped sharply in the immediate road shoulder which indicated high disturbance conditions that few species were able to tolerate. To our knowledge, we are the first to demonstrate that the access mode to a recreation site influences the potential of certain impacts, such as the increase of non-native species, to self-perpetuate from their points of introduction to disjointed sites with a predisposition to disturbance. Due to this propulsion of impacts, the overall spatial extent of roadside impacts was far greater than initially apparent from assessments at the road verge. We discuss possible means of mitigating these impacts. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Simulations show decreasing carbon stocks and potential for carbon emissions in Rocky Mountain forests over the next century.

    Science.gov (United States)

    Boisvenue, Céline; Running, Steven W

    2010-07-01

    Climate change has altered the environment in which forests grow, and climate change models predict more severe alterations to come. Forests have already responded to these changes, and the future temperature and precipitation scenarios are of foremost concern, especially in the mountainous western United States, where forests occur in the dry environments that interface with grasslands. The objective of this study was to understand the trade-offs between temperature and water controls on these forested sites in the context of available climate projections. Three temperature and precipitation scenarios from IPCC AR4 AOGCMs ranging in precipitation levels were input to the process model Biome-BGC for key forested sites in the northern U.S. Rocky Mountains. Despite the omission of natural and human-caused disturbances in our simulations, our results show consequential effects from these conservative future temperature and precipitation scenarios. According to these projections, if future precipitation and temperatures are similar to or drier than the dry scenario depicted here, high-elevation forests on both the drier and wetter sites, which have in the absence of disturbance accumulated carbon, will reduce their carbon accumulation. Under the marginally drier climate projections, most forests became carbon sources by the end of the simulation horizon (2089). Under all three scenarios, growing season lengthened, the number of days with snow on the ground decreased, peak snow occurred earlier, and water stress increased through the projection horizon (1950-2089) for all sites, which represent the temperature and precipitation spectrum of forests in this region. The quantity, form, and timing of precipitation ultimately drive the carbon accumulation trajectory of forests in this region.

  15. Factorization method and new potentials from the inverted oscillator

    International Nuclear Information System (INIS)

    Bermudez, David; Fernández C, David J.

    2013-01-01

    In this article we will apply the first- and second-order supersymmetric quantum mechanics to obtain new exactly-solvable real potentials departing from the inverted oscillator potential. This system has some special properties; in particular, only very specific second-order transformations produce non-singular real potentials. It will be shown that these transformations turn out to be the so-called complex ones. Moreover, we will study the factorization method applied to the inverted oscillator and the algebraic structure of the new Hamiltonians. -- Highlights: •We apply supersymmetric quantum mechanics to the inverted oscillator potential. •The complex second-order transformations allow us to build new non-singular potentials. •The algebraic structure of the initial and final potentials is analyzed. •The initial potential is described by a complex-deformed Heisenberg–Weyl algebra. •The final potentials are described by polynomial Heisenberg algebras

  16. A simple method for potential flow simulation of cascades

    Indian Academy of Sciences (India)

    vortex panel method to simulate potential flow in cascades is presented. The cascade ... The fluid loading on the blades, such as the normal force and pitching moment, may ... of such discrete infinite array singularities along the blade surface.

  17. THE METHODS FOR ESTIMATING REGIONAL PROFESSIONAL MOBILE RADIO MARKET POTENTIAL

    Directory of Open Access Journals (Sweden)

    Y.À. Korobeynikov

    2008-12-01

    Full Text Available The paper represents the author’s methods of estimating regional professional mobile radio market potential, that belongs to high-tech b2b markets. These methods take into consideration such market peculiarities as great range and complexity of products, technological constraints and infrastructure development for the technological systems operation. The paper gives an estimation of professional mobile radio potential in Perm region. This estimation is already used by one of the systems integrator for its strategy development.

  18. Using the Screened Coulomb Potential to Illustrate the Variational Method

    Science.gov (United States)

    Zuniga, Jose; Bastida, Adolfo; Requena, Alberto

    2012-01-01

    The screened Coulomb potential, or Yukawa potential, is used to illustrate the application of the single and linear variational methods. The trial variational functions are expressed in terms of Slater-type functions, for which the integrals needed to carry out the variational calculations are easily evaluated in closed form. The variational…

  19. The potential of high resolution ultrasonic in-situ methods

    International Nuclear Information System (INIS)

    Schuster, K.

    2010-01-01

    Document available in extended abstract form only. In the framework of geomechanical assessment of final repository underground openings the knowledge of geophysical rock parameters are of importance. Ultrasonic methods proved to be good geophysical tools to provide appropriate high resolution parameters for the characterisation of rock. In this context the detection and characterisation of rock heterogeneities at different scales, including the Excavation Damaged/disturbed Zone (EDZ/EdZ) features, play an important role. Especially, kinematic and dynamic parameters derived from ultrasonic measurements can be linked very close to rock mechanic investigations and interpretations. BGR uses high resolution ultrasonic methods, starting with emitted frequencies of about 1 kHz (seismic) and going up to about 100 kHz. The method development is going on and appropriate research and investigations are performed since many years at different European radioactive waste disposal related underground research laboratories in different potential host rocks. The most frequented are: Mont Terri Rock Laboratory, Switzerland (Opalinus Clay, OPA), Underground Research Laboratory Meuse/Haute- Marne, France (Callovo-Oxfordian, COX), Underground Research Facility Mol, Belgium (Boom Clay, BC), Aespoe Hard Rock Laboratory, Sweden (granites), Rock Laboratory Grimsel, Switzerland (granites) and Asse salt mine, Germany (rock salt). The methods can be grouped into borehole based methods and noninvasive methods like refraction and reflection methods, which are performed in general from the drift wall. Additionally, as a combination of these both methods a sort of vertical seismic profiling (VSP) is applied. The best qualified method, or a combination of methods, have to be chosen according to the scientific questions and the local site conditions. The degree of spatial resolution of zones of interest or any kind of anomaly depends strongly on the distance of these objects to the ultrasonic

  20. Method-Based Higher Education in Sustainability: The Potential of the Scenario Method

    Directory of Open Access Journals (Sweden)

    Richard Beecroft

    2014-05-01

    Full Text Available Both sustainability and education are challenging process-oriented objectives. When the aim is to combine both notions, as in Higher Education in Sustainability (HES, it is indispensable to first establish a common ground between them. In this paper, we characterise this common ground in terms of four aspects: future orientation, normativity, global perspective, and theory engaged in practice. Based on an analysis of the common ground, one method that is well-established in a wide range of sustainability sciences shows high potential for use in HES because it covers all four aspects in detail: the scenario method. We argue that a didactical reconstruction of the scenario method is necessary to utilise its potential and develop adequate forms of teaching in higher education. The scenario method is used to construct and analyse a set of alternative future developments to support decisions that have to be made in the present. Didactical reconstruction reveals a spectrum of objectives for which the scenario method can be employed: (1 projection; (2 teleological planning and (3 an explorative search for possibilities not yet considered. By studying and experimenting with this spectrum of objectives, students in HES can develop fundamental reflexive competencies in addressing the future in different ways that are relevant for both sustainability and education.

  1. The auxiliary field method and approximate analytical solutions of the Schroedinger equation with exponential potentials

    Energy Technology Data Exchange (ETDEWEB)

    Silvestre-Brac, Bernard [LPSC Universite Joseph Fourier, Grenoble 1, CNRS/IN2P3, Institut Polytechnique de Grenoble, Avenue des Martyrs 53, F-38026 Grenoble-Cedex (France); Semay, Claude; Buisseret, Fabien [Groupe de Physique Nucleaire Theorique, Universite de Mons-Hainaut, Academie universitaire Wallonie-Bruxelles, Place du Parc 20, B-7000 Mons (Belgium)], E-mail: silvestre@lpsc.in2p3.fr, E-mail: claude.semay@umh.ac.be, E-mail: fabien.buisseret@umh.ac.be

    2009-06-19

    The auxiliary field method is a new and efficient way to compute approximate analytical eigenenergies of the Schroedinger equation. This method has already been successfully applied to the case of central potentials of power-law and logarithmic forms. In the present work, we show that the Schroedinger equation with exponential potentials of the form -{alpha}r{sup {lambda}}exp(-{beta}r) can also be analytically solved by using the auxiliary field method. Closed formulae giving the critical heights and the energy levels of these potentials are presented. Special attention is drawn to the Yukawa potential and the pure exponential potential.

  2. The auxiliary field method and approximate analytical solutions of the Schroedinger equation with exponential potentials

    International Nuclear Information System (INIS)

    Silvestre-Brac, Bernard; Semay, Claude; Buisseret, Fabien

    2009-01-01

    The auxiliary field method is a new and efficient way to compute approximate analytical eigenenergies of the Schroedinger equation. This method has already been successfully applied to the case of central potentials of power-law and logarithmic forms. In the present work, we show that the Schroedinger equation with exponential potentials of the form -αr λ exp(-βr) can also be analytically solved by using the auxiliary field method. Closed formulae giving the critical heights and the energy levels of these potentials are presented. Special attention is drawn to the Yukawa potential and the pure exponential potential

  3. Application of potential harmonic expansion method to BEC

    Indian Academy of Sciences (India)

    We adopt the potential harmonics expansion method for an ab initio solution of the many-body system in a Bose condensate containing interacting bosons. Unlike commonly adopted mean-field theories, our method is capable of handling two-body correlation properly. We disregard three- and higher-body correlations.

  4. Improvement of economic potential estimation methods for enterprise with potential branch clusters use

    Directory of Open Access Journals (Sweden)

    V.Ya. Nusinov

    2017-08-01

    Full Text Available The research determines that the current existing methods of enterprise’s economic potential estimation are based on the use of additive, multiplicative and rating models. It is determined that the existing methods have a row of defects. For example, not all the methods take into account the branch features of the analysis, and also the level of development of the enterprise comparatively with other enterprises. It is suggested to level such defects by an account at the estimation of potential integral level not only by branch features of enterprises activity but also by the intra-account economic clusterization of such enterprises. Scientific works which are connected with the using of clusters for the estimation of economic potential are generalized. According to the results of generalization it is determined that it is possible to distinguish 9 scientific approaches in this direction: the use of natural clusterization of enterprises with the purpose of estimation and increase of region potential; the use of natural clusterization of enterprises with the purpose of estimation and increase of industry potential; use of artificial clusterization of enterprises with the purpose of estimation and increase of region potential; use of artificial clusterization of enterprises with the purpose of estimation and increase of industry potential; the use of artificial clusterization of enterprises with the purpose of clustering potential estimation; the use of artificial clusterization of enterprises with the purpose of estimation of clustering competitiveness potential; the use of natural (artificial clusterization for the estimation of clustering efficiency; the use of natural (artificial clusterization for the increase of level at region (industries development; the use of methods of economic potential of region (industries estimation or its constituents for the construction of the clusters. It is determined that the use of clusterization method in

  5. Meta-Analysis of Quantification Methods Shows that Archaea and Bacteria Have Similar Abundances in the Subseafloor

    Science.gov (United States)

    May, Megan K.; Kevorkian, Richard T.; Steen, Andrew D.

    2013-01-01

    There is no universally accepted method to quantify bacteria and archaea in seawater and marine sediments, and different methods have produced conflicting results with the same samples. To identify best practices, we compiled data from 65 studies, plus our own measurements, in which bacteria and archaea were quantified with fluorescent in situ hybridization (FISH), catalyzed reporter deposition FISH (CARD-FISH), polyribonucleotide FISH, or quantitative PCR (qPCR). To estimate efficiency, we defined “yield” to be the sum of bacteria and archaea counted by these techniques divided by the total number of cells. In seawater, the yield was high (median, 71%) and was similar for FISH, CARD-FISH, and polyribonucleotide FISH. In sediments, only measurements by CARD-FISH in which archaeal cells were permeabilized with proteinase K showed high yields (median, 84%). Therefore, the majority of cells in both environments appear to be alive, since they contain intact ribosomes. In sediments, the sum of bacterial and archaeal 16S rRNA gene qPCR counts was not closely related to cell counts, even after accounting for variations in copy numbers per genome. However, qPCR measurements were precise relative to other qPCR measurements made on the same samples. qPCR is therefore a reliable relative quantification method. Inconsistent results for the relative abundance of bacteria versus archaea in deep subsurface sediments were resolved by the removal of CARD-FISH measurements in which lysozyme was used to permeabilize archaeal cells and qPCR measurements which used ARCH516 as an archaeal primer or TaqMan probe. Data from best-practice methods showed that archaea and bacteria decreased as the depth in seawater and marine sediments increased, although archaea decreased more slowly. PMID:24096423

  6. Comparative study of methods for potential and actual evapotranspiration determination

    International Nuclear Information System (INIS)

    Kolev, B.

    2004-01-01

    Two types of methods for potential and actual evapotranspiration determining were compared. The first type includes neutron gauge, tensiometers, gypsum blocks and lysimeters. The actual and potential evapotranspiration were calculated by water balance equation. The second type of methods used a simulation model for all calculation. The aim of this study was not only to compare and estimate the methods using. It was mainly pointed on calculations of water use efficiency and transpiration coefficient in potential production situation. This makes possible to choose the best way for water consumption optimization for a given crop. The final results find with the best of the methods could be used for applying the principles of sustainable agriculture in random region of Bulgarian territory. (author)

  7. A method to determine the mammographic regions that show early changes due to the development of breast cancer

    Science.gov (United States)

    Karemore, Gopal; Nielsen, Mads; Karssemeijer, Nico; Brandt, Sami S.

    2014-11-01

    It is well understood nowadays that changes in the mammographic parenchymal pattern are an indicator of a risk of breast cancer and we have developed a statistical method that estimates the mammogram regions where the parenchymal changes, due to breast cancer, occur. This region of interest is computed from a score map by utilising the anatomical breast coordinate system developed in our previous work. The method also makes an automatic scale selection to avoid overfitting while the region estimates are computed by a nested cross-validation scheme. In this way, it is possible to recover those mammogram regions that show a significant difference in classification scores between the cancer and the control group. Our experiments suggested that the most significant mammogram region is the region behind the nipple and that can be justified by previous findings from other research groups. This result was conducted on the basis of the cross-validation experiments on independent training, validation and testing sets from the case-control study of 490 women, of which 245 women were diagnosed with breast cancer within a period of 2-4 years after the baseline mammograms. We additionally generalised the estimated region to another, mini-MIAS study and showed that the transferred region estimate gives at least a similar classification result when compared to the case where the whole breast region is used. In all, by following our method, one most likely improves both preclinical and follow-up breast cancer screening, but a larger study population will be required to test this hypothesis.

  8. A method to determine the mammographic regions that show early changes due to the development of breast cancer

    International Nuclear Information System (INIS)

    Karemore, Gopal; Nielsen, Mads; Brandt, Sami S; Karssemeijer, Nico

    2014-01-01

    It is well understood nowadays that changes in the mammographic parenchymal pattern are an indicator of a risk of breast cancer and we have developed a statistical method that estimates the mammogram regions where the parenchymal changes, due to breast cancer, occur. This region of interest is computed from a score map by utilising the anatomical breast coordinate system developed in our previous work. The method also makes an automatic scale selection to avoid overfitting while the region estimates are computed by a nested cross-validation scheme. In this way, it is possible to recover those mammogram regions that show a significant difference in classification scores between the cancer and the control group. Our experiments suggested that the most significant mammogram region is the region behind the nipple and that can be justified by previous findings from other research groups. This result was conducted on the basis of the cross-validation experiments on independent training, validation and testing sets from the case-control study of 490 women, of which 245 women were diagnosed with breast cancer within a period of 2–4 years after the baseline mammograms. We additionally generalised the estimated region to another, mini-MIAS study and showed that the transferred region estimate gives at least a similar classification result when compared to the case where the whole breast region is used. In all, by following our method, one most likely improves both preclinical and follow-up breast cancer screening, but a larger study population will be required to test this hypothesis. (paper)

  9. Assessment of Soil Liquefaction Potential Based on Numerical Method

    DEFF Research Database (Denmark)

    Choobasti, A. Janalizadeh; Vahdatirad, Mohammad Javad; Torabi, M.

    2012-01-01

    Paying special attention to geotechnical hazards such as liquefaction in huge civil projects like urban railways especially in susceptible regions to liquefaction is of great importance. A number of approaches to evaluate the potential for initiation of liquefaction, such as Seed and Idriss...... simplified method have been developed over the years. Although simplified methods are available in calculating the liquefaction potential of a soil deposit and shear stresses induced at any point in the ground due to earthquake loading, these methods cannot be applied to all earthquakes with the same...... accuracy, also they lack the potential to predict the pore pressure developed in the soil. Therefore, it is necessary to carry out a ground response analysis to obtain pore pressures and shear stresses in the soil due to earthquake loading. Using soil historical, geological and compositional criteria...

  10. Quantitative method of measuring cancer cell urokinase and metastatic potential

    Science.gov (United States)

    Morrison, Dennis R. (Inventor)

    1993-01-01

    The metastatic potential of tumors can be evaluated by the quantitative detection of urokinase and DNA. The cell sample selected for examination is analyzed for the presence of high levels of urokinase and abnormal DNA using analytical flow cytometry and digital image analysis. Other factors such as membrane associated urokinase, increased DNA synthesis rates and certain receptors can be used in the method for detection of potentially invasive tumors.

  11. Enterprise’s employment potential: concept, components and evaluation methods

    Directory of Open Access Journals (Sweden)

    Korbut K.Ye.

    2017-06-01

    Full Text Available The present study deals with the main interpretations and views of scientists on the economic category «labor potential». The conditions and factors affecting the labor potential are given. The author makes the classification and provides the general characteristic to the factors, which characterize the mechanism of formation of the labor potential. The detailed description of the main components and the components of the labor potential at the enterprise has been determined, analyzed and provided. The levels of the labor potential manifestation are summarized, and examined, and the explanation is given to each of them. The general characteristic of the constituent elements of workers’ labor potential is provided. The principal data of the labor potential at the micro level are provided. The main types of the labor potential at the enterprise are singled out and characterized in detail by the level of aggregated estimates, by the range of coverage of opportunities, by the nature of participation in the production and economic process and by the place in the socio-economic system of the enterprise. Considerable attention is paid to the views of scientists on the main methods of assessing the labor potential of the enterprise.

  12. Split kinetic energy method for quantum systems with competing potentials

    International Nuclear Information System (INIS)

    Mineo, H.; Chao, Sheng D.

    2012-01-01

    For quantum systems with competing potentials, the conventional perturbation theory often yields an asymptotic series and the subsequent numerical outcome becomes uncertain. To tackle such a kind of problems, we develop a general solution scheme based on a new energy dissection idea. Instead of dividing the potential energy into “unperturbed” and “perturbed” terms, a partition of the kinetic energy is performed. By distributing the kinetic energy term in part into each individual potential, the Hamiltonian can be expressed as the sum of the subsystem Hamiltonians with respective competing potentials. The total wavefunction is expanded by using a linear combination of the basis sets of respective subsystem Hamiltonians. We first illustrate the solution procedure using a simple system consisting of a particle under the action of double δ-function potentials. Next, this method is applied to the prototype systems of a charged harmonic oscillator in strong magnetic field and the hydrogen molecule ion. Compared with the usual perturbation approach, this new scheme converges much faster to the exact solutions for both eigenvalues and eigenfunctions. When properly extended, this new solution scheme can be very useful for dealing with strongly coupling quantum systems. - Highlights: ► A new basis set expansion method is proposed. ► Split kinetic energy method is proposed to solve quantum eigenvalue problems. ► Significant improvement has been obtained in converging to exact results. ► Extension of such methods is promising and discussed.

  13. Construction of molecular potential energy curves by an optimization method

    Science.gov (United States)

    Wang, J.; Blake, A. J.; McCoy, D. G.; Torop, L.

    1991-01-01

    A technique for determining the potential energy curves for diatomic molecules from measurements of diffused or continuum spectra is presented. It is based on a numerical procedure which minimizes the difference between the calculated spectra and the experimental measurements and can be used in cases where other techniques, such as the conventional RKR method, are not applicable. With the aid of suitable spectral data, the associated dipole electronic transition moments can be simultaneously obtained. The method is illustrated by modeling the "longest band" of molecular oxygen to extract the E 3Σ u- and B 3Σ u- potential curves in analytical form.

  14. A new PCR-based method shows that blue crabs (Callinectes sapidus (Rathbun)) consume winter flounder (Pseudopleuronectes americanus (Walbaum)).

    Science.gov (United States)

    Collier, Jackie L; Fitzgerald, Sean P; Hice, Lyndie A; Frisk, Michael G; McElroy, Anne E

    2014-01-01

    Winter flounder (Pseudopleuronectes americanus) once supported robust commercial and recreational fisheries in the New York (USA) region, but since the 1990s populations have been in decline. Available data show that settlement of young-of-the-year winter flounder has not declined as sharply as adult abundance, suggesting that juveniles are experiencing higher mortality following settlement. The recent increase of blue crab (Callinectes sapidus) abundance in the New York region raises the possibility that new sources of predation may be contributing to juvenile winter flounder mortality. To investigate this possibility we developed and validated a method to specifically detect winter flounder mitochondrial control region DNA sequences in the gut contents of blue crabs. A survey of 55 crabs collected from Shinnecock Bay (along the south shore of Long Island, New York) in July, August, and September of 2011 showed that 12 of 42 blue crabs (28.6%) from which PCR-amplifiable DNA was recovered had consumed winter flounder in the wild, empirically supporting the trophic link between these species that has been widely speculated to exist. This technique overcomes difficulties with visual identification of the often unrecognizable gut contents of decapod crustaceans, and modifications of this approach offer valuable tools to more broadly address their feeding habits on a wide variety of species.

  15. The Methodical Approaches to Activation of Innovative Potential of Enterprise

    Directory of Open Access Journals (Sweden)

    Berveno Oksana V.

    2017-12-01

    Full Text Available The article is aimed at developing theoretical provisions and practical recommendations on methods of management and activation of innovative potential of enterprises. Assessment of innovative potential of enterprise should be carried out from different positions, taking into consideration all external and internal possibilities of enterprise as to carrying out an innovation activity. The system of management of innovation activity and implementation of innovative potential at enterprise should be closely woven in the general management of the enterprise. Activation of innovative potential of enterprise foresees adoption of the whole system of strategic decisions, which are aimed at creation of the most favorable conditions for implementation of innovative potential with obtaining of planned results. The system of activization of innovative potential should develop a number of organizational decisions on interaction of elements of the most innovative potential in the process of innovation activity and cooperation of innovative potential with other subsystems of the enterprise. Results of these organizational decisions in many respects determine efficiency of innovation activity of the enterprise.

  16. Quality of potential harmonics expansion method for dilute Bose ...

    Indian Academy of Sciences (India)

    Abstract. We present and examine an approximate but ab initio many-body approach, viz., potential harmonics expansion method (PHEM), which includes two-body correla- tions for dilute Bose–Einstein condensates. Comparing the total ground state energy for three trapped interacting bosons calculated in PHEM with the ...

  17. First Generation College Student Leadership Potential: A Mixed Methods Analysis

    Science.gov (United States)

    Hojan-Clark, Jane M.

    2010-01-01

    This mixed methods research compared the leadership potential of traditionally aged first generation college students to that of college students whose parents are college educated. A college education provides advantages to those who can obtain it (Baum & Payea, 2004; Black Issues in Higher Education, 2005; Education and the Value of…

  18. Comparison of different methods for estimation of potential evapotranspiration

    International Nuclear Information System (INIS)

    Nazeer, M.

    2010-01-01

    Evapotranspiration can be estimated with different available methods. The aim of this research study to compare and evaluate the originally measured potential evapotranspiration from Class A pan with the Hargreaves equation, the Penman equation, the Penman-Montheith equation, and the FAO56 Penman-Monteith equation. The evaporation rate from pan recorded greater than stated methods. For each evapotranspiration method, results were compared against mean monthly potential evapotranspiration (PET) from Pan data according to FAO (ET/sub o/=K/sub pan X E/sub pan)), from daily measured recorded data of the twenty-five years (1984-2008). On the basis of statistical analysis between the pan data and the FAO56- Penman-Monteith method are not considered to be very significant (=0.98) at 95% confidence and prediction intervals. All methods required accurate weather data for precise results, for the purpose of this study the past twenty five years data were analyzed and used including maximum and minimum air temperature, relative humidity, wind speed, sunshine duration and rainfall. Based on linear regression analysis results the FAO56 PMM ranked first (R/sup 2/=0.98) followed by Hergreaves method (R/sup 2/=0.96), Penman-Monteith method (R/sup 2/=0.94) and Penman method (=0.93). Obviously, using FAO56 Penman Monteith method with precise climatic variables for ET/sub o/ estimation is more reliable than the other alternative methods, Hergreaves is more simple and rely only on air temperatures data and can be used alternative of FAO56 Penman-Monteith method if other climatic data are missing or unreliable. (author)

  19. Development of an investigation method for redox condition of rocks by self potential (SP) method

    International Nuclear Information System (INIS)

    Kubota, Kenji; Inohara, Yoshiki; Oyama, Takahiro

    2012-01-01

    One of the major issues in subsurface disposal of low level radioactive wastes is that long term behaviors of sedimentary rocks can be affected by geochemical factors. Redox conditions can affect to corrosion of metal included in artificial barrier or wastes and adsorption characteristics of a nuclide. Therefore, it is necessary to develop a method for evaluating the redox conditions around natural barrier at waste facilities. In general, geochemical properties are acquired by rock samples or water sampling at a borehole. However, there is a possibility not to acquire data we want to evaluate. If geophysical methods are applied, redox conditions can be evaluated widely and briefly. There is a possibility that self potential (SP) and redox conditions have a correlation. So we have conducted self potential method around test caverns where redox front can be observed at the Rokkasho site. The results demonstrated that self potential decreased around redox front. There was a positive correlation between self potential and pH. One of the factors of self potential change is difference of elevation, however, self potential change around redox front was larger than that expected from elevation difference. Zeta potential is one of the important factors for determination of self potential, and it had a correlation with self potential or pH. Therefore, there is a possibility that self potential change occurs by geochemical condition changes around redox front, and redox condition can be detected by self potential method. (author)

  20. Redox potentials of free radicals. III. Reevaluation of the method

    International Nuclear Information System (INIS)

    Rao, P.S.; Hayon, E.

    1974-01-01

    A reevaluation of the method described in ref 1 and 2 to determine the redox potentials of free radicals (.RH) in water using the techniques of pulse radiolysis and absorption spectrophotometry is presented. This method is based on the dependence of the percentage efficiency for the one-electron oxidation (or reduction) of .RH radicals on the redox potentials E 01 of the electron acceptors, A. The reaction .RH + A → .A - + R + H + (kappa/sub ox/) is not reversible for most radicals under the experimental conditions used, and the derived potentials are, therefore, not thermodynamic values. A reinterpretation of the results is made on the basis of the kinetic competition between the above reaction and .RH + A → .RHA (kappa/sub add/) (radical adducts). Based on kappa/ sub ox/ and kappa/sub add/, it is concluded that the observed experimental ''titration'' curves do represent a measure of the redox property of the free radicals. From the midpoint on the curves, the kinetic potential, E/sub kappa/ 01 : of the free radicals can be derived based on the known two-electron redox potentials of the electron acceptors. These and other questions are discussed. (U.S.)

  1. Non-standard perturbative methods for the effective potential in λφ4 QFT

    International Nuclear Information System (INIS)

    Okopinska, A.

    1986-07-01

    The effective potential in scalar QFT is calculated in the non-standard perturbative methods and compared with the conventional loop expansion. In the space time dimensions 0 and 1 the results are compared with the ''exact'' effective potential obtained numerically. In 4 dimensions we show that λφ 4 theory is non-interacting. (author)

  2. Numerical method for the unsteady potential flow about pitching airfoils

    International Nuclear Information System (INIS)

    Parrouffe, J.-M.; Paraschivoiu, I.

    1985-01-01

    This paper presents a numerical method for the unsteady potential flow about an aerodynamic profile and in its wake. This study has many applications such as airplane wings and propellers, guide vanes, subcavitant hydrofoils and wind turbine blades. Typical of such nonstationary configurations is the rotor of the Darrieus vertical-axis wind turbine whose blades are exposed to cyclic aerodynamic loads in the operating state

  3. Theoretical studies of potential energy surfaces and computational methods

    Energy Technology Data Exchange (ETDEWEB)

    Shepard, R. [Argonne National Laboratory, IL (United States)

    1993-12-01

    This project involves the development, implementation, and application of theoretical methods for the calculation and characterization of potential energy surfaces involving molecular species that occur in hydrocarbon combustion. These potential energy surfaces require an accurate and balanced treatment of reactants, intermediates, and products. This difficult challenge is met with general multiconfiguration self-consistent-field (MCSCF) and multireference single- and double-excitation configuration interaction (MRSDCI) methods. In contrast to the more common single-reference electronic structure methods, this approach is capable of describing accurately molecular systems that are highly distorted away from their equilibrium geometries, including reactant, fragment, and transition-state geometries, and of describing regions of the potential surface that are associated with electronic wave functions of widely varying nature. The MCSCF reference wave functions are designed to be sufficiently flexible to describe qualitatively the changes in the electronic structure over the broad range of geometries of interest. The necessary mixing of ionic, covalent, and Rydberg contributions, along with the appropriate treatment of the different electron-spin components (e.g. closed shell, high-spin open-shell, low-spin open shell, radical, diradical, etc.) of the wave functions, are treated correctly at this level. Further treatment of electron correlation effects is included using large scale multireference CI wave functions, particularly including the single and double excitations relative to the MCSCF reference space. This leads to the most flexible and accurate large-scale MRSDCI wave functions that have been used to date in global PES studies.

  4. Brevican-deficient mice display impaired hippocampal CA1 long-term potentiation but show no obvious deficits in learning and memory

    DEFF Research Database (Denmark)

    Brakebusch, Cord; Seidenbecher, Constanze I; Asztely, Fredrik

    2002-01-01

    to be less prominent in mutant than in wild-type mice. Brevican-deficient mice showed significant deficits in the maintenance of hippocampal long-term potentiation (LTP). However, no obvious impairment of excitatory and inhibitory synaptic transmission was found, suggesting a complex cause for the LTP defect....... Detailed behavioral analysis revealed no statistically significant deficits in learning and memory. These data indicate that brevican is not crucial for brain development but has restricted structural and functional roles....

  5. Application of the Asymptotic Taylor Expansion Method to Bistable Potentials

    Directory of Open Access Journals (Sweden)

    Okan Ozer

    2013-01-01

    Full Text Available A recent method called asymptotic Taylor expansion (ATEM is applied to determine the analytical expression for eigenfunctions and numerical results for eigenvalues of the Schrödinger equation for the bistable potentials. Optimal truncation of the Taylor series gives a best possible analytical expression for eigenfunctions and numerical results for eigenvalues. It is shown that the results are obtained by a simple algorithm constructed for a computer system using symbolic or numerical calculation. It is observed that ATEM produces excellent results consistent with the existing literature.

  6. Parametric potential determination by the canonical function method

    International Nuclear Information System (INIS)

    Tannous, C.; Fakhreddine, K.; Langlois, J.

    1999-01-01

    The canonical function method (CFM) is a powerful means for solving the radial Schroedinger equation (RSE). The mathematical difficulty of the RSE lies in the fact it is a singular boundary value problem. The CFM turns it into a regular initial value problem and allows the full determination of the spectrum of the Schroedinger operator without calculating the eigenfunctions. Following the parametrisation suggested by Klapisch and Green-Sellin-Zachor we develop a CFM to optimise the potential parameters in order to reproduce the experimental quantum defect results for various Rydberg series of He, Ne and Ar as evaluated from Moore's data. (orig.)

  7. Motion Planning for Omnidirectional Wheeled Mobile Robot by Potential Field Method

    Directory of Open Access Journals (Sweden)

    Weihao Li

    2017-01-01

    Full Text Available In this paper, potential field method has been used to navigate a three omnidirectional wheels’ mobile robot and to avoid obstacles. The potential field method is used to overcome the local minima problem and the goals nonreachable with obstacles nearby (GNRON problem. For further consideration, model predictive control (MPC has been used to incorporate motion constraints and make the velocity more realistic and flexible. The proposed method is employed based on the kinematic model and dynamics model of the mobile robot in this paper. To show the performance of proposed control scheme, simulation studies have been carried to perform the motion process of mobile robot in specific workplace.

  8. Monitoring crack growth by a potential drop method

    International Nuclear Information System (INIS)

    Tomlinson, J.R.

    1978-01-01

    A theoretical model has been developed for the surface current flow and potential distribution around a surface breaking crack. This model's predictions have been confirmed in the laboratory and the method applied on site. It proved possible by careful design and rigorous testing to overcome the problems of interference in an electrically noisy environment. The principal weaknesses of the technique are that it is only capable of detecting cracks that break the accessible surface of the component, and that there may be problems with conductive bridging across the crack. On the other hand, the lack of any sophisticated probe in contact with the component makes the method suitable for high temperature use, and, being an electrical method, it is capable of continuous use. The use of a.c., as opposed to d.c., enables lower currents to be used. Given good access to the crack tip, a high sensitivity can be obtained, which enables noise rejection to be achieved with the use of a high threshold. (orig.) [de

  9. Vitamin B1-deficient mice show impairment of hippocampus-dependent memory formation and loss of hippocampal neurons and dendritic spines: potential microendophenotypes of Wernicke-Korsakoff syndrome.

    Science.gov (United States)

    Inaba, Hiroyoshi; Kishimoto, Takuya; Oishi, Satoru; Nagata, Kan; Hasegawa, Shunsuke; Watanabe, Tamae; Kida, Satoshi

    2016-12-01

    Patients with severe Wernicke-Korsakoff syndrome (WKS) associated with vitamin B1 (thiamine) deficiency (TD) show enduring impairment of memory formation. The mechanisms of memory impairment induced by TD remain unknown. Here, we show that hippocampal degeneration is a potential microendophenotype (an endophenotype of brain disease at the cellular and synaptic levels) of WKS in pyrithiamine-induced thiamine deficiency (PTD) mice, a rodent model of WKS. PTD mice show deficits in the hippocampus-dependent memory formation, although they show normal hippocampus-independent memory. Similarly with WKS, impairments in memory formation did not recover even at 6 months after treatment with PTD. Importantly, PTD mice exhibit a decrease in neurons in the CA1, CA3, and dentate gyrus (DG) regions of the hippocampus and reduced density of wide dendritic spines in the DG. Our findings suggest that TD induces hippocampal degeneration, including the loss of neurons and spines, thereby leading to enduring impairment of hippocampus-dependent memory formation.

  10. Vitamin B1-deficient mice show impairment of hippocampus-dependent memory formation and loss of hippocampal neurons and dendritic spines: potential microendophenotypes of Wernicke–Korsakoff syndrome

    Science.gov (United States)

    Inaba, Hiroyoshi; Kishimoto, Takuya; Oishi, Satoru; Nagata, Kan; Hasegawa, Shunsuke; Watanabe, Tamae; Kida, Satoshi

    2016-01-01

    Patients with severe Wernicke–Korsakoff syndrome (WKS) associated with vitamin B1 (thiamine) deficiency (TD) show enduring impairment of memory formation. The mechanisms of memory impairment induced by TD remain unknown. Here, we show that hippocampal degeneration is a potential microendophenotype (an endophenotype of brain disease at the cellular and synaptic levels) of WKS in pyrithiamine-induced thiamine deficiency (PTD) mice, a rodent model of WKS. PTD mice show deficits in the hippocampus-dependent memory formation, although they show normal hippocampus-independent memory. Similarly with WKS, impairments in memory formation did not recover even at 6 months after treatment with PTD. Importantly, PTD mice exhibit a decrease in neurons in the CA1, CA3, and dentate gyrus (DG) regions of the hippocampus and reduced density of wide dendritic spines in the DG. Our findings suggest that TD induces hippocampal degeneration, including the loss of neurons and spines, thereby leading to enduring impairment of hippocampus-dependent memory formation. PMID:27576603

  11. Interleaved Carbon Minibeams: An Experimental Radiosurgery Method With Clinical Potential

    Energy Technology Data Exchange (ETDEWEB)

    Dilmanian, F. Avraham, E-mail: dilmanian@bnl.gov [Medical Department, Brookhaven National Laboratory, Upton, NY (United States); Department of Radiation Oncology, Stony Brook University Medical Center, NY (United States); Department of Neurology, Stony Brook University Medical Center, NY (United States); Rusek, Adam [NASA Space Radiation Laboratory, Brookhaven National Laboratory, Upton, NY (United States); Fois, Giovanna R. [Medical Department, Brookhaven National Laboratory, Upton, NY (United States); Physics Department, University of Cagliari, Sardinia (Italy); Olschowka, John [Department of Neurobiology and Anatomy, University of Rochester, Rochester, NY (United States); Desnoyers, Nicolle R. [Medical Department, Brookhaven National Laboratory, Upton, NY (United States); Ross University School of Veterinary Medicine, Basseterre, St. Kitts, West Indies (Country Unknown); Park, Jane Y. [Medical Department, Brookhaven National Laboratory, Upton, NY (United States); College of Veterinary Medicine, Cornell University, Ithaca, NY (United States); Dioszegi, Istvan [Nonproliferation and National Security Department, Brookhaven National Laboratory, Upton, NY (United States); Dane, Bari; Wang Ruiliang [Medical Department, Brookhaven National Laboratory, Upton, NY (United States); Tomasi, Dardo [Medical Department, Brookhaven National Laboratory, Upton, NY (United States); National Institute on Alcoholism and Alcohol Abuse, Bethesda, MD (United States); Lee, Hedok [Medical Department, Brookhaven National Laboratory, Upton, NY (United States); Hurley, Sean D. [Department of Neurobiology and Anatomy, University of Rochester, Rochester, NY (United States); Coyle, Patricia K. [Department of Neurology, Stony Brook University Medical Center, NY (United States); Meek, Allen G. [Department of Radiation Oncology, Stony Brook University Medical Center, NY (United States); O' Banion, M. Kerry [Department of Neurobiology and Anatomy, University of Rochester, Rochester, NY (United States)

    2012-10-01

    Purpose: To evaluate the efficacy of 'interleaved carbon minibeams' for ablating a 6.5-mm target in a rabbit brain with little damage to the surrounding brain. The method is based on the well-established tissue-sparing effect of arrays of thin planes of radiation. Methods and Materials: Broad carbon beams from the National Aeronautics and Space Agency Space Radiation Facility at Brookhaven National Laboratory were segmented into arrays of parallel, horizontal, 0.3-mm-thick planar beams (minibeams). The minibeams' gradual broadening in tissues resulted in 0.525-mm beam thickness at the target's proximal side in the spread-out Bragg peak. Interleaving was therefore implemented by choosing a 1.05 mm beam spacing on-center. The anesthetized rabbit, positioned vertically on a stage capable of rotating about a vertical axis, was exposed to arrays from four 90 Degree-Sign angles, with the stage moving up by 0.525 mm in between. This produced a solid radiation field at the target while exposing the nontargeted tissues to single minibeam arrays. The target 'physical' absorbed dose was 40.2 Gy. Results: The rabbit behaved normally during the 6-month observation period. Contrast magnetic resonance imaging and hematoxylin and eosin histology at 6 months showed substantial focal target damage with little damage to the surrounding brain. Conclusion: We plan to evaluate the method's therapeutic efficacy by comparing it with broad-beam carbon therapy in animal models. The method's merits would combine those of carbon therapy (i.e., tight target dose because of the carbon's Bragg-peak, sharp dose falloff, and high relative biological effectiveness at the target), together with the method's low impact on the nontargeted tissues. The method's smaller impact on the nontargeted brain might allow carbon therapy at higher target doses and/or lower normal tissue impact, thus leading to a more effective treatment of radioresistant

  12. The overlapping distribution method to compute chemical potentials of chain molecules

    NARCIS (Netherlands)

    Mooij, G.C.A.M.; Frenkel, D.

    1994-01-01

    The chemical potential of continuously deformable chain molecules can be estimated by measuring the average Rosenbluth weight associated with the virtual insertion of a molecule. We show how to generalize the overlapping-distribution method of Bennett to histograms of Rosenbluth weights. In this way

  13. A Comparative Study of Potential Evapotranspiration Estimation by Eight Methods with FAO Penman–Monteith Method in Southwestern China

    Directory of Open Access Journals (Sweden)

    Dengxiao Lang

    2017-09-01

    Full Text Available Potential evapotranspiration (PET is crucial for water resources assessment. In this regard, the FAO (Food and Agriculture Organization–Penman–Monteith method (PM is commonly recognized as a standard method for PET estimation. However, due to requirement of detailed meteorological data, the application of PM is often constrained in many regions. Under such circumstances, an alternative method with similar efficiency to that of PM needs to be identified. In this study, three radiation-based methods, Makkink (Mak, Abtew (Abt, and Priestley–Taylor (PT, and five temperature-based methods, Hargreaves–Samani (HS, Thornthwaite (Tho, Hamon (Ham, Linacre (Lin, and Blaney–Criddle (BC, were compared with PM at yearly and seasonal scale, using long-term (50 years data from 90 meteorology stations in southwest China. Indicators, viz. (videlicet Nash–Sutcliffe efficiency (NSE, relative error (Re, normalized root mean squared error (NRMSE, and coefficient of determination (R2 were used to evaluate the performance of PET estimations by the above-mentioned eight methods. The results showed that the performance of the methods in PET estimation varied among regions; HS, PT, and Abt overestimated PET, while others underestimated. In Sichuan basin, Mak, Abt and HS yielded similar estimations to that of PM, while, in Yun-Gui plateau, Abt, Mak, HS, and PT showed better performances. Mak performed the best in the east Tibetan Plateau at yearly and seasonal scale, while HS showed a good performance in summer and autumn. In the arid river valley, HS, Mak, and Abt performed better than the others. On the other hand, Tho, Ham, Lin, and BC could not be used to estimate PET in some regions. In general, radiation-based methods for PET estimation performed better than temperature-based methods among the selected methods in the study area. Among the radiation-based methods, Mak performed the best, while HS showed the best performance among the temperature

  14. Alkaliphilic Bacillus species show potential application in concrete crack repair by virtue of rapid spore production and germination then extracellular calcite formation.

    Science.gov (United States)

    Sharma, T K; Alazhari, M; Heath, A; Paine, K; Cooper, R M

    2017-05-01

    Characterization of alkaliphilic Bacillus species for spore production and germination and calcite formation as a prelude to investigate their potential in microcrack remediation in concrete. Conditions, extent and timing of endospore production was determined by dark-field light microscopy; germination induction and kinetics were assessed by combining reduction in optical density with formation of refractile bodies by phase-contrast microscopy. Bacillus pseudofirmus was selected from several species as the most suitable isolate. Levels and timing of calcium carbonate precipitated in vitro by B. pseudofirmus were evaluated by atomic absorption spectroscopy and structural identity confirmed as calcite and aragonite by Raman spectroscopy and FTIR. The isolate produced copious spores that germinated rapidly in the presence of germinants l-alanine, inosine and NaCl. Bacterial cells produced CaCO 3 crystals in microcracks and the resulting occlusion markedly restricted water ingress. By virtue of rapid spore production and germination, calcium carbonate formation in vitro and in situ, leading to sealing of microcracks, B. pseudofirmus shows clear potential for remediation of concrete on a commercial scale. Microbial sealing of microcracks should become a practicable and sustainable means of increasing concrete durability. © 2017 The Authors. Journal of Applied Microbiology published by John Wiley & Sons Ltd on behalf of The Society for Applied Microbiology.

  15. Aging is associated with an expansion of CD49fhi mammary stem cells that show a decline in function and increased transformation potential.

    Science.gov (United States)

    Dong, Qiaoxiang; Gao, Hui; Shi, Yuanshuo; Zhang, Fuchuang; Gu, Xiang; Wu, Anqi; Wang, Danhan; Chen, Yuanhong; Bandyopadhyay, Abhik; Yeh, I-Tien; Daniel, Benjamin J; Chen, Yidong; Zou, Yi; Rebel, Vivienne L; Walter, Christi A; Lu, Jianxin; Huang, Changjiang; Sun, Lu-Zhe

    2016-11-15

    Breast cancer incidence increases during aging, yet the mechanism of age-associated mammary tumorigenesis is unclear. Mammary stem cells are believed to play an important role in breast tumorigenesis, but how their function changes with age is unknown. We compared mammary epithelial cells isolated from young and old mammary glands of different cohorts of C57BL6/J and BALB/c mice, and our findings revealed that old mammary glands were characterized by increased basal cell pool comprised of mostly CD49f hi cells, altered luminal-to-basal cell ratio, and irregular ductal morphology. More interestingly, basal stem cells in old mice were increased in frequency, but showed a functional decline of differentiation and increased neoplastic transformation potential. Gene signature enrichment analysis revealed a significant enrichment of a luminal cell gene expression signature in the basal stem cell-enriched population from old mice, suggesting some luminal cells were expressing basal markers. Immunofluorescence staining confirmed the presence of luminal cells with high CD49f expression in hyperplastic lesions implicating these cells as undergoing luminal to basal phenotypic changes during aging. Whole transcriptome analysis showed elevated immune and inflammatory responses in old basal stem cells and stromal cells, which may be the underlying cause for increased CD49f hi basal-like cells in aged glands.

  16. Adolescent mice show anxiety- and aggressive-like behavior and the reduction of long-term potentiation in mossy fiber-CA3 synapses after neonatal maternal separation.

    Science.gov (United States)

    Shin, S Y; Han, S H; Woo, R-S; Jang, S H; Min, S S

    2016-03-01

    Exposure to maternal separation (MS) during early life is an identified risk factor for emotional disorders such as anxiety and depression later in life. This study investigated the effects of neonatal MS on the behavior and long-term potentiation (LTP) as well as basic synaptic transmission at hippocampal CA3-CA1 and mossy fiber (MF)-CA3 synapses in adolescent mice for 19days. When mice were adolescents, we measured depression, learning, memory, anxious and aggressive behavior using the forced swimming test (FST), Y-maze, Morris water maze (MWM), elevated plus maze (EPM), three consecutive days of the open field test, the social interaction test, the tube-dominance test and the resident-intruder test. The results showed that there was no difference in FST, Y-maze, and MWM performance. However, MS mice showed more anxiety-like behavior in the EPM test and aggressive-like behavior in the tube-dominance and resident-intruder tests. In addition, the magnitude of LTP and release probability in the MF-CA3 synapses was reduced in the MS group but not in the CA3-CA1 synapse. Our results indicate that early life stress due to MS may induce anxiety- and aggressive-like behavior during adolescence, and these effects are associated with synaptic plasticity at the hippocampal MF-CA3 synapses. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

  17. Solution of Dirac equation for modified Poschl Teller plus trigonometric Scarf potential using Romanovsky polynomials method

    International Nuclear Information System (INIS)

    Prastyaningrum, I.; Cari, C.; Suparmi, A.

    2016-01-01

    The approximation analytical solution of Dirac equation for Modified Poschl Teller plus Trigonometric Scarf Potential are investigated numerically in terms of finite Romanovsky Polynomial. The combination of two potentials are substituted into Dirac Equation then the variables are separated into radial and angular parts. The Dirac equation is solved by using Romanovsky Polynomial Method. The equation that can reduce from the second order of differential equation into the differential equation of hypergeometry type by substituted variable method. The energy spectrum is numerically solved using Matlab 2011. Where the increase in the radial quantum number nr and variable of modified Poschl Teller Potential causes the energy to decrease. The radial and the angular part of the wave function also visualized with Matlab 2011. The results show, by the disturbance of a combination between this potential can change the wave function of the radial and angular part. (paper)

  18. Interleaved Carbon Minibeams: An Experimental Radiosurgery Method With Clinical Potential

    International Nuclear Information System (INIS)

    Dilmanian, F. Avraham; Rusek, Adam; Fois, Giovanna R.; Olschowka, John; Desnoyers, Nicolle R.; Park, Jane Y.; Dioszegi, Istvan; Dane, Bari; Wang Ruiliang; Tomasi, Dardo; Lee, Hedok; Hurley, Sean D.; Coyle, Patricia K.; Meek, Allen G.; O’Banion, M. Kerry

    2012-01-01

    Purpose: To evaluate the efficacy of “interleaved carbon minibeams” for ablating a 6.5-mm target in a rabbit brain with little damage to the surrounding brain. The method is based on the well-established tissue-sparing effect of arrays of thin planes of radiation. Methods and Materials: Broad carbon beams from the National Aeronautics and Space Agency Space Radiation Facility at Brookhaven National Laboratory were segmented into arrays of parallel, horizontal, 0.3-mm-thick planar beams (minibeams). The minibeams’ gradual broadening in tissues resulted in 0.525-mm beam thickness at the target’s proximal side in the spread-out Bragg peak. Interleaving was therefore implemented by choosing a 1.05 mm beam spacing on-center. The anesthetized rabbit, positioned vertically on a stage capable of rotating about a vertical axis, was exposed to arrays from four 90° angles, with the stage moving up by 0.525 mm in between. This produced a solid radiation field at the target while exposing the nontargeted tissues to single minibeam arrays. The target “physical” absorbed dose was 40.2 Gy. Results: The rabbit behaved normally during the 6-month observation period. Contrast magnetic resonance imaging and hematoxylin and eosin histology at 6 months showed substantial focal target damage with little damage to the surrounding brain. Conclusion: We plan to evaluate the method’s therapeutic efficacy by comparing it with broad-beam carbon therapy in animal models. The method’s merits would combine those of carbon therapy (i.e., tight target dose because of the carbon’s Bragg-peak, sharp dose falloff, and high relative biological effectiveness at the target), together with the method’s low impact on the nontargeted tissues. The method’s smaller impact on the nontargeted brain might allow carbon therapy at higher target doses and/or lower normal tissue impact, thus leading to a more effective treatment of radioresistant tumors. It should also make the method more

  19. The Differential Proteome of the Probiotic Lactobacillus acidophilus NCFM Grown on the Potential Prebiotic Cellobiose Shows Upregulation of Two β-Glycoside Hydrolases

    Directory of Open Access Journals (Sweden)

    Gabriella C. van Zanten

    2015-01-01

    Full Text Available Probiotics, prebiotics, and combinations thereof, that is, synbiotics, are known to exert beneficial health effects in humans; however interactions between pro- and prebiotics remain poorly understood at the molecular level. The present study describes changes in abundance of different proteins of the probiotic bacterium Lactobacillus acidophilus NCFM (NCFM when grown on the potential prebiotic cellobiose as compared to glucose. Cytosolic cell extract proteomes after harvest at late exponential phase of NCFM grown on cellobiose or glucose were analyzed by two dimensional difference gel electrophoresis (2D-DIGE in the acidic (pH 4–7 and the alkaline (pH 6–11 regions showing a total of 136 spots to change in abundance. Proteins were identified by MS or MS/MS from 81 of these spots representing 49 unique proteins and either increasing 1.5–13.9-fold or decreasing 1.5–7.8-fold in relative abundance. Many of these proteins were associated with energy metabolism, including the cellobiose related glycoside hydrolases phospho-β-glucosidase (LBA0881 and phospho-β-galactosidase II (LBA0726. The data provide insight into the utilization of the candidate prebiotic cellobiose by the probiotic bacterium NCFM. Several of the upregulated or downregulated identified proteins associated with utilization of cellobiose indicate the presence of carbon catabolite repression and regulation of enzymes involved in carbohydrate metabolism.

  20. Virgin coconut oil (VCO) by normalizing NLRP3 inflammasome showed potential neuroprotective effects in Amyloid-β induced toxicity and high-fat diet fed rat.

    Science.gov (United States)

    Mirzaei, Fatemeh; Khazaei, Mozafar; Komaki, Alireza; Amiri, Iraj; Jalili, Cyrus

    2018-05-02

    Both dyslipidemia and Alzheimer disease (AD) are associated with aging. In this study, the effects of virgin coconut oil (VCO) on inflammasome and oxidative stress in Alzheimer's model (receiving Amyloid-β (Aβ)) and high-fat diet (HFD) model were determined. A total of 120 male Wistar rats, were divided into 12 groups (n = 10), including; healthy control, sham surgery, sham surgery receiving normal saline, HFD, HFD + 8% VCO, HFD + 10% VCO, Aβ received rats, Aβ + 8%VCO, Aβ + 10%VCO, HFD + Aβ, HFD + Aβ+8%VCO, and HFD + Aβ + 10%VCO. Following memory and learning tests, blood sample prepared from the heart and hippocampus of rats in each group was kept at -70 °C for genes expression, oxidative stress, and biochemical tests. Aβ and HFD significantly impaired memory and learning by activating of both NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome and oxidative stress (p<0.05), while treatment with both 8 and 10% VCO normalized inflammasome genes expression and oxidative stress (p<0.05). The Congo Red, Cresyl Violet staining and immunohistochemistry (IHC) test revealed that VCO improved hippocampus histological changes, reduced Aβ plaques and phosphorylated Tau. High-fat diet has exacerbated the effects of Aβ, while VCO showed potential neuroprotective effect. Copyright © 2018 Elsevier Ltd. All rights reserved.

  1. Numerical Solutions of the Mean-Value Theorem: New Methods for Downward Continuation of Potential Fields

    Science.gov (United States)

    Zhang, Chong; Lü, Qingtian; Yan, Jiayong; Qi, Guang

    2018-04-01

    Downward continuation can enhance small-scale sources and improve resolution. Nevertheless, the common methods have disadvantages in obtaining optimal results because of divergence and instability. We derive the mean-value theorem for potential fields, which could be the theoretical basis of some data processing and interpretation. Based on numerical solutions of the mean-value theorem, we present the convergent and stable downward continuation methods by using the first-order vertical derivatives and their upward continuation. By applying one of our methods to both the synthetic and real cases, we show that our method is stable, convergent and accurate. Meanwhile, compared with the fast Fourier transform Taylor series method and the integrated second vertical derivative Taylor series method, our process has very little boundary effect and is still stable in noise. We find that the characters of the fading anomalies emerge properly in our downward continuation with respect to the original fields at the lower heights.

  2. The Socratic method in teaching medical ethics: potentials and limitations.

    Science.gov (United States)

    Birnbacher, D

    1999-01-01

    The Socratic method has a long history in teaching philosophy and mathematics, marked by such names as Karl Weierstrass, Leonard Nelson and Gustav Heckmann. Its basic idea is to encourage the participants of a learning group (of pupils, students, or practitioners) to work on a conceptual, ethical or psychological problem by their own collective intellectual effort, without a textual basis and without substantial help from the teacher whose part it is mainly to enforce the rigid procedural rules designed to ensure a fruitful, diversified, open and consensus-oriented thought process. Several features of the Socratic procedure, especially in the canonical form given to it by Heckmann, are highly attractive for the teaching of medical ethics in small groups: the strategy of starting from relevant singular individual experiences, interpreting and cautiously generalizing them in a process of inter-subjective confrontation and confirmation, the duty of non-directivity on the part of the teacher in regard to the contents of the discussion, the necessity, on the part of the participants, to make explicit both their own thinking and the way they understand the thought of others, the strict separation of content level and meta level discussion and, not least, the wise use made of the emotional and motivational resources developing in the group process. Experience shows, however, that the canonical form of the Socratic group suffers from a number of drawbacks which may be overcome by loosening the rigidity of some of the rules. These concern mainly the injunction against substantial interventions on the part of the teacher and the insistence on consensus formation rooted in Leonard Nelson's Neo-Kantian Apriorism.

  3. Advanced enzymology, expression profile and immune response of Clonorchis sinensis hexokinase show its application potential for prevention and control of clonorchiasis.

    Directory of Open Access Journals (Sweden)

    Tingjin Chen

    2015-03-01

    Full Text Available Approximately 35 million people are infected with Clonorchis sinensis (C. sinensis globally, of whom 15 million are in China. Glycolytic enzymes are recognized as crucial molecules for trematode survival and have been targeted for vaccine and drug development. Hexokinase of C. sinensis (CsHK, as the first key regulatory enzyme of the glycolytic pathway, was investigated in the current study.There were differences in spatial structure and affinities for hexoses and phosphate donors between CsHK and HKs from humans or rats, the definitive hosts of C. sinensis. Effectors (AMP, PEP, and citrate and a small molecular inhibitor regulated the enzymatic activity of rCsHK, and various allosteric systems were detected. CsHK was distributed in the worm extensively as well as in liver tissue and serum from C. sinensis infected rats. Furthermore, high-level specific IgG1 and IgG2a were induced in rats by immunization with rCsHK. The enzymatic activity of CsHK was suppressed by the antibody in vitro. Additionally, the survival of C. sinensis was inhibited by the antibody in vivo and in vitro.Due to differences in putative spatial structure and enzymology between CsHK and HK from the host, its extensive distribution in adult worms, and its expression profile as a component of excretory/secretory products, together with its good immunogenicity and immunoreactivity, as a key glycolytic enzyme, CsHK shows potential as a vaccine and as a promising drug target for Clonorchiasis.

  4. Advanced enzymology, expression profile and immune response of Clonorchis sinensis hexokinase show its application potential for prevention and control of clonorchiasis.

    Science.gov (United States)

    Chen, Tingjin; Yu, Jinyun; Tang, Zeli; Xie, Zhizhi; Lin, Zhipeng; Sun, Hengchang; Wan, Shuo; Li, Xuerong; Huang, Yan; Yu, Xinbing; Xu, Jin

    2015-03-01

    Approximately 35 million people are infected with Clonorchis sinensis (C. sinensis) globally, of whom 15 million are in China. Glycolytic enzymes are recognized as crucial molecules for trematode survival and have been targeted for vaccine and drug development. Hexokinase of C. sinensis (CsHK), as the first key regulatory enzyme of the glycolytic pathway, was investigated in the current study. There were differences in spatial structure and affinities for hexoses and phosphate donors between CsHK and HKs from humans or rats, the definitive hosts of C. sinensis. Effectors (AMP, PEP, and citrate) and a small molecular inhibitor regulated the enzymatic activity of rCsHK, and various allosteric systems were detected. CsHK was distributed in the worm extensively as well as in liver tissue and serum from C. sinensis infected rats. Furthermore, high-level specific IgG1 and IgG2a were induced in rats by immunization with rCsHK. The enzymatic activity of CsHK was suppressed by the antibody in vitro. Additionally, the survival of C. sinensis was inhibited by the antibody in vivo and in vitro. Due to differences in putative spatial structure and enzymology between CsHK and HK from the host, its extensive distribution in adult worms, and its expression profile as a component of excretory/secretory products, together with its good immunogenicity and immunoreactivity, as a key glycolytic enzyme, CsHK shows potential as a vaccine and as a promising drug target for Clonorchiasis.

  5. Potential new methods of detection of irradiated food

    International Nuclear Information System (INIS)

    Raffi, J.J.

    1991-01-01

    The irradiation of food by X- and gamma-rays and by electron beams is a technological process which may be used for food preservation in addition to heat or chemical treatment. The role of the Community Bureau of Reference - the BCR programme - in this area is to support the development and the improvement of analytical methods required for the preparation and implementation of the European legislation. In this context, after consultation of specialists in the Member States and the EFTA countries, it was decided that the BCR should undertake a collaborative project for the identification of irradiated food. The aim of the Cadarache workshop was to examine the development of new methods of detection and to set up a concerted research action covering four areas: DNA based methods; microbiological and biological methods; physical methods; chemical methods

  6. The potential for new methods to assess human reproductive genotoxicity

    International Nuclear Information System (INIS)

    Mendelsohn, M.L.

    1987-09-01

    The immediate prospects are not good for practical methods for measuring the human heritable mutation rate. The methods discussed here range from speculative to impractical, and at best are sensitive enough only for large numbers of subjects. Given the rapid development of DNA methods and the current status of two-dimensional gel electrophoresis, there is some hope that the intermediate prospects may be better. In contrast, the prospects for useful cellular-based male germinal methods seem more promising and immediate. Effective specific locus methods for sperm are already conceivable and may be practical in a few years. Obviously such methods will not predict heritable effects definitively, but they will provide direct information on reproductive genotoxicity and should contribute significantly to many current medical and environmental situations where genetic damage is suspected. 22 refs

  7. A Potential Reduction Method for Canonical Duality, with an Application to the Sensor Network Localization Problem

    OpenAIRE

    Latorre, Vittorio

    2014-01-01

    We propose to solve large instances of the non-convex optimization problems reformulated with canonical duality theory. To this aim we propose an interior point potential reduction algorithm based on the solution of the primal-dual total complementarity (Lagrange) function. We establish the global convergence result for the algorithm under mild assumptions and demonstrate the method on instances of the Sensor Network Localization problem. Our numerical results are promising and show the possi...

  8. Finite element transport methods for criticality calculations - current status and potential applications

    International Nuclear Information System (INIS)

    Oliveira, C.R.E. de; Goddard, A.

    1991-01-01

    In this paper we review the current status of the finite element method applied to the solution of the neutron transport equation and we discuss its potential role in the field of criticality safety. We show that the method's ability in handling complex, irregular geometry in two- and three-dimensions coupled with its accurate solutions potentially renders it an attractive alternative to the longer-established Monte Carlo method. Details of the most favoured form of the method - that which combines finite elements in space and spherical harmonics in angle - are presented. This form of the method, which has been extensively investigated over the last decade by research groups at the University of London, has been numerically implemented in the finite element code EVENT. The code has among its main features the capability of solving fixed source eigenvalue and time-dependent complex geometry problems in two- and three-dimensions. Other features of the code include anisotropic up- and down-scatter, direct and/or adjoint solutions and access to standard data libraries. Numerical examples, ranging from simple criticality benchmark studies to the analysis of idealised three-dimensional reactor cores, are presented to demonstrate the potential of the method. (author)

  9. Methods for the numerical calculation of the plasma potential from measured Langmuir probe characteristics

    International Nuclear Information System (INIS)

    Seifert, W.; Johanning, D.; Bankov, N.

    1986-01-01

    In a previous paper the results of the Langmuir probe experiment carried out on board of two INTERKOSMOS satellites have been described. The experiences have shown that the usage of high quality algorithms for analyzing the current-voltage-characteristics is necessary to yield real physical parameters. The key problem is the determination of the plasma potential. This paper reviews the different methods to determine the plasma potential especially under the circumstances of computer application. The test of the well developed methods shows, that for the evaluation of the applied methods a number of different factors, discussed in the following sections of this paper, has to be taken into account. The used test data are model values or real measurements obtained by the satellite missions IK-10, IK-18 and BULGARIA-1300. The computer procedures have been realized as FORTRAN-subroutines for the BESM 6 and ES 1040. (author)

  10. The dimension split element-free Galerkin method for three-dimensional potential problems

    Science.gov (United States)

    Meng, Z. J.; Cheng, H.; Ma, L. D.; Cheng, Y. M.

    2018-02-01

    This paper presents the dimension split element-free Galerkin (DSEFG) method for three-dimensional potential problems, and the corresponding formulae are obtained. The main idea of the DSEFG method is that a three-dimensional potential problem can be transformed into a series of two-dimensional problems. For these two-dimensional problems, the improved moving least-squares (IMLS) approximation is applied to construct the shape function, which uses an orthogonal function system with a weight function as the basis functions. The Galerkin weak form is applied to obtain a discretized system equation, and the penalty method is employed to impose the essential boundary condition. The finite difference method is selected in the splitting direction. For the purposes of demonstration, some selected numerical examples are solved using the DSEFG method. The convergence study and error analysis of the DSEFG method are presented. The numerical examples show that the DSEFG method has greater computational precision and computational efficiency than the IEFG method.

  11. Methods for direct measurement of the plasma potential

    DEFF Research Database (Denmark)

    Andersen, S. A.; Christoffersen, G. B.; Jensen, Vagn Orla

    1972-01-01

    Reports on a simple experimental technique which can be used for determination of the plasma where the plasma potential prevails; these ions are accepted by the analyser plate when phi c= phi pl. Part of this technique has been used by Andersen, Jensen, Michelsen and Nielsen (1971) in measurements...

  12. Comparison of three methods for the estimation of cross-shock electric potential using Cluster data

    Directory of Open Access Journals (Sweden)

    A. P. Dimmock

    2011-05-01

    Full Text Available Cluster four point measurements provide a comprehensive dataset for the separation of temporal and spatial variations, which is crucial for the calculation of the cross shock electrostatic potential using electric field measurements. While Cluster is probably the most suited among present and past spacecraft missions to provide such a separation at the terrestrial bow shock, it is far from ideal for a study of the cross shock potential, since only 2 components of the electric field are measured in the spacecraft spin plane. The present paper is devoted to the comparison of 3 different techniques that can be used to estimate the potential with this limitation. The first technique is the estimate taking only into account the projection of the measured components onto the shock normal. The second uses the ideal MHD condition E·B = 0 to estimate the third electric field component. The last method is based on the structure of the electric field in the Normal Incidence Frame (NIF for which only the potential component along the shock normal and the motional electric field exist. All 3 approaches are used to estimate the potential for a single crossing of the terrestrial bow shock that took place on the 31 March 2001. Surprisingly all three methods lead to the same order of magnitude for the cross shock potential. It is argued that the third method must lead to more reliable results. The effect of the shock normal inaccuracy is investigated for this particular shock crossing. The resulting electrostatic potential appears too high in comparison with the theoretical results for low Mach number shocks. This shows the variability of the potential, interpreted in the frame of the non-stationary shock model.

  13. Inversion of potential field data using the finite element method on parallel computers

    Science.gov (United States)

    Gross, L.; Altinay, C.; Shaw, S.

    2015-11-01

    In this paper we present a formulation of the joint inversion of potential field anomaly data as an optimization problem with partial differential equation (PDE) constraints. The problem is solved using the iterative Broyden-Fletcher-Goldfarb-Shanno (BFGS) method with the Hessian operator of the regularization and cross-gradient component of the cost function as preconditioner. We will show that each iterative step requires the solution of several PDEs namely for the potential fields, for the adjoint defects and for the application of the preconditioner. In extension to the traditional discrete formulation the BFGS method is applied to continuous descriptions of the unknown physical properties in combination with an appropriate integral form of the dot product. The PDEs can easily be solved using standard conforming finite element methods (FEMs) with potentially different resolutions. For two examples we demonstrate that the number of PDE solutions required to reach a given tolerance in the BFGS iteration is controlled by weighting regularization and cross-gradient but is independent of the resolution of PDE discretization and that as a consequence the method is weakly scalable with the number of cells on parallel computers. We also show a comparison with the UBC-GIF GRAV3D code.

  14. Corrosion potential detection method, potential characteristic simulation method for reaction rate and plant monitoring system using the same

    International Nuclear Information System (INIS)

    Sakai, Masanori; Onaka, Noriyuki; Takahashi, Tatsuya; Yamanaka, Hiroshi.

    1995-01-01

    In a calculation controlling device for a plant monitoring system, concentrations of materials concerning reaction materials in a certain state of a reaction process, and an actually measured value for the potential of a material in this state are substituted into a reaction rate equation obtained in accordance with a reaction process model. With such procedures, a relation between the reaction rate (current value) and the potential of the material can be obtained. A potential at which the reaction rates of an anode reaction and a cathode reaction contained in a corrosion reaction are made equal is determined by a numerical value calculation, based on an electrochemical hybrid potential logic by using the reaction rate equation, the reaction rate information relative to the corrosion reaction of the material and the concentration of the material concerning the corrosion reaction is obtained by a numerical value calculation. Then, simulation for the corrosion potential is enabled based on the handling corresponding to the actual reaction. Further, even for a portion which can not be measured actually, the corrosion potential can be recognized by simulation. (N.H.)

  15. Determinantal method for complex angular momenta in potential scattering

    Energy Technology Data Exchange (ETDEWEB)

    Lee, B. W. [University of Pennsylvania, Philadelphia, PA (United States)

    1963-01-15

    In this paper I would like do describe a formulation of the complex angular momenta in potential scattering based on the Lippmann-Schwinger integral equation rather than on the Schrödinger differential equation. This is intended as a preliminary to the paper by SAWYER on the Regge poles and high energy limits in field theory (Bethe-Salpeter amplitudes), where the integral formulation is definitely more advantageous than the differential formulation.

  16. Sliding surface searching method for slopes containing a potential weak structural surface

    Directory of Open Access Journals (Sweden)

    Aijun Yao

    2014-06-01

    Full Text Available Weak structural surface is one of the key factors controlling the stability of slopes. The stability of rock slopes is in general concerned with set of discontinuities. However, in soft rocks, failure can occur along surfaces approaching to a circular failure surface. To better understand the position of potential sliding surface, a new method called simplex-finite stochastic tracking method is proposed. This method basically divides sliding surface into two parts: one is described by smooth curve obtained by random searching, the other one is polyline formed by the weak structural surface. Single or multiple sliding surfaces can be considered, and consequently several types of combined sliding surfaces can be simulated. The paper will adopt the arc-polyline to simulate potential sliding surface and analyze the searching process of sliding surface. Accordingly, software for slope stability analysis using this method was developed and applied in real cases. The results show that, using simplex-finite stochastic tracking method, it is possible to locate the position of a potential sliding surface in the slope.

  17. Comparison of different methods in estimating potential evapotranspiration at Muda Irrigation Scheme of Malaysia

    Directory of Open Access Journals (Sweden)

    Sobri Harun

    2012-04-01

    Full Text Available Evapotranspiration (ET is a complex process in the hydrological cycle that influences the quantity of runoff and thus the irrigation water requirements. Numerous methods have been developed to estimate potential evapotranspiration (PET. Unfortunately, most of the reliable PET methods are parameter rich models and therefore, not feasible for application in data scarce regions. On the other hand, accuracy and reliability of simple PET models vary widely according to regional climate conditions. The objective of the present study was to evaluate the performance of three temperature-based and three radiation-based simple ET methods in estimating historical ET and projecting future ET at Muda Irrigation Scheme at Kedah, Malaysia. The performance was measured by comparing those methods with the parameter intensive Penman-Monteith Method. It was found that radiation based methods gave better performance compared to temperature-based methods in estimation of ET in the study area. Future ET simulated from projected climate data obtained through statistical downscaling technique also showed that radiation-based methods can project closer ET values to that projected by Penman-Monteith Method. It is expected that the study will guide in selecting suitable methods for estimating and projecting ET in accordance to availability of meteorological data.

  18. The steady performance prediction of propeller-rudder-bulb system based on potential iterative method

    International Nuclear Information System (INIS)

    Liu, Y B; Su, Y M; Ju, L; Huang, S L

    2012-01-01

    A new numerical method was developed for predicting the steady hydrodynamic performance of propeller-rudder-bulb system. In the calculation, the rudder and bulb was taken into account as a whole, the potential based surface panel method was applied both to propeller and rudder-bulb system. The interaction between propeller and rudder-bulb was taken into account by velocity potential iteration in which the influence of propeller rotation was considered by the average influence coefficient. In the influence coefficient computation, the singular value should be found and deleted. Numerical results showed that the method presented is effective for predicting the steady hydrodynamic performance of propeller-rudder system and propeller-rudder-bulb system. Comparing with the induced velocity iterative method, the method presented can save programming and calculation time. Changing dimensions, the principal parameter—bulb size that affect energy-saving effect was studied, the results show that the bulb on rudder have a optimal size at the design advance coefficient.

  19. Objectively Determining the Educational Potential of Computer and Video-Based Courseware; or, Producing Reliable Evaluations Despite the Dog and Pony Show.

    Science.gov (United States)

    Barrett, Andrew J.; And Others

    The Center for Interactive Technology, Applications, and Research at the College of Engineering of the University of South Florida (Tampa) has developed objective and descriptive evaluation models to assist in determining the educational potential of computer and video courseware. The computer-based courseware evaluation model and the video-based…

  20. Biogeography of Aegagropila linnaei (Cladophorophyceae, Chlorophyta): a widespread freshwater alga with low effective dispersal potential shows a glacial imprint in its distribution

    NARCIS (Netherlands)

    Boedeker, C.; Eggert, A.; Immers, A.; Wakana, I.

    2010-01-01

    Aim:Aegagropila linnaei is a freshwater macroalga that is generally regarded as a rare species. It is apparently absent from large but seemingly suitable areas of the Northern Hemisphere, implying a limited dispersal potential and an imprint of Pleistocene glaciations in its biogeography. However,

  1. Supersymmetry, reflectionless symmetric potentials and the inverse method

    International Nuclear Information System (INIS)

    Bagchi, B.

    1990-01-01

    The role of inverse scattering method is illustrated to examine the connection between the multi-soliton solutions of Korteweg-de Vries (KdV) equation and discrete eigenvalues of Schrodinger equation. The necessity of normalization of the Schrodinger wave functions, which are constructed purely from a supersymmetric consideration is pointed out

  2. Method of renormalization potential for one model of Hartree-Fock-Slater type

    CERN Document Server

    Zasorin, Y V

    2002-01-01

    A new method of the potential renormalization for the quasiclassical model of the Hartree-Fock-Slater real potential is proposed. The method makes it possible to easily construct the wave functions and contrary to the majority od similar methods it does not require the knowledge of the real-type potential

  3. Radioisotope method potentialities in machine reliability and durability enhancement

    International Nuclear Information System (INIS)

    Postnikov, V.I.

    1975-01-01

    The development of a surface activation method is reviewed with regard to wear of machine parts. Examples demonstrating the highly promising aspects and practical application of the method are cited. The use of high-sensitivity instruments and variation of activation depth from 10 um to 0.5 mm allows to perform the investigations at a sensitivity of 0.05 um and to estimate the linear values of machine wear. Standard diagrams are presented for measuring the wear of different machine parts by means of surface activation. Investigations performed at several Soviet technological institutes afford a set of dependences, which characterize the distribution of radioactive isotopes in depth under different conditions of activation of diverse metals and alloys and permit to study the wear of any metal

  4. Canonical transformations method in the potential scattering problem

    International Nuclear Information System (INIS)

    Pavlenko, Yu.G.

    1984-01-01

    Canonical formalism of the first order is used in the present paper to solve the problem of scattering and other problems of quantum mechanics. The theory of canonical transformations (CT) being the basis of hamiltonian approach permits to develop several methods of integration being beyond the scope of the standard theory of perturbations. In this case it is essential for numerical counting that the theory permits to obtain algorithm for plotting highest approximations

  5. Coupling Empowerment Based Application of Extension Method for Geothermal Potential Assessment

    Directory of Open Access Journals (Sweden)

    Qing Zhang

    2018-01-01

    Full Text Available Plenty of mathematics researches provide feasibility to calculate the weights of geothermal controlling factors and have been applied in geothermal potential assessment. In order to avoid the disadvantages of subjective and objective weighting calculation methods, an extension theory integrated weighting method was put forward, by combining with the process of AHP and mean variance method. The improved method can reach an agreement on subjective understanding of impact factors’ roles and data-based calculation weights. Then by replacing the point values with intervals, the extension theory was used in classification of geothermal assessment, according to extension judgment matrix. The evaluation results showed perfect performance in classification of impact factors, especially in Wudalianchi area, where 10 out of 11 selected impact factors agreed well with the actual evaluation grades. The study can provide a guidance for primary stage of geothermal investigation including the impact factor selection, weights calculation for impact factors, and the factors’ classification in geothermal assessment.

  6. In-Situ Creep Monitoring Using the Potential Drop Method

    Science.gov (United States)

    Madhi, E.; Sposito, G.; Davies, C. M.; Cawley, P.; Nagy, P. B.

    2011-06-01

    A directional low-frequency Alternating Current Potential Drop (ACPD) sensor was developed for in-situ monitoring of creep in metals. The sensor relies on a modified ACPD technique that measures simultaneously both values of resistance in the axial and lateral directions using a square electrode configuration. As compared to the more commonly used in-line electrode configuration, the square arrangement used in this sensor is much more directional and thus allows the detection of creep-induced anisotropy and texture. The technique monitors the variation in the ratio of the measured axial and lateral resistances, therefore can efficiently separate the mostly isotropic common part of the resistivity variation caused by reversible temperature variations from the mostly anisotropic differential part caused by direct geometrical and indirect material effects of creep. Initially, this ratio is roughly proportional to the axial creep strain, while at later stages, the resistance ratio increases even faster with creep strain because of the formation of directional discontinuities such as preferentially oriented grain boundary cavities and multiple-site microcracks in the material.

  7. Potential National Security Applications of Nuclear Resonance Fluorescence Methods

    International Nuclear Information System (INIS)

    Warren, Glen A.; Peplowski, Patrick N.; Caggiano, Joseph A.

    2009-01-01

    The objective of this report is to document the initial investigation into the possible research issues related to the development of NRF-based national security applications. The report discusses several potential applications ranging from measuring uranium enrichment in UF6 canisters to characterization of gas samples. While these applications are varied, there are only a few research issues that need to be addressed to understand the limitation of NRF in solving these problems. These research issues range from source and detector development to measuring small samples. The next effort is to determine how best to answer the research issues, followed by a prioritization of those questions to ensure that the most important are addressed. These issues will be addressed through either analytical calculations, computer simulations, analysis of previous data or collection of new measurements. It will also be beneficial to conduct a thorough examination of a couple of the more promising applications in order to develop concrete examples of how NRF may be applied in specific situations. The goals are to develop an understanding of whether the application of NRF is limited by technology or physics in addressing national security applications, to gain a motivation to explore those possible applications, and to develop a research roadmap so that those possibilities may be made reality.

  8. The effect of PBL and film showing, frequent quizzes and lecture-based method on short-term performance of dentistry students

    Directory of Open Access Journals (Sweden)

    Sadr Lahijani M.S

    2004-01-01

    Full Text Available Background: Advocates have proposed that frequent testing increases the effectiveness of instruction by encouraging learners to study and review more often. It has also been argued that in this way, student errors can be identified and corrected earlier and good performance can be recognized, leading to more positive attitudes toward learning process. In problem-based learning (PBL, medical students reportedly take a more active role in learning and have better recall than students in a conventional learning environment. The hypothetical benefits of a PBL and studentbased environment and use of films in the class are the development of self-learning and problem-solving skills and enhancement of knowledge and motivation. Purpose: To examine the effect of combination of PBL method and film showing on the short-term performance of dentistry students and to compare it with lecture-based method and frequent quizzes. Methods: All students of 3 years (from 2000 till 2002 that had theoretical endodontic course (part 1 participated in this descriptive-analytic study. The scores of final examinations of this course were obtained from their files. Data were analyzed by SPSS software & ANOVA. Results: The results showed that by changing the way of learning (PBL and film showing in 2001, there was a statistical difference between scores of the students of 2000 and 2001. Also there was a statistical difference with the students’ scores in 2002- the group with frequent quizzes. Conclusion: The variables such as changing the way of learning, using different methods in teaching, showing scientific films in class or, as a whole, active learning have significant effects on the results of final examination. Key Words: PBL, lecture based method, education, frequent quizzes

  9. Carcinogenicity study of 3-monochloropropane-1, 2-diol (3-MCPD) administered by drinking water to B6C3F1 mice showed no carcinogenic potential.

    Science.gov (United States)

    Jeong, Jayoung; Han, Beom Seok; Cho, Wan-Seob; Choi, Mina; Ha, Chang-Su; Lee, Byoung-Seok; Kim, Yong-Bum; Son, Woo-Chan; Kim, Choong-Yong

    2010-09-01

    3-Monochloropropane-1, 2-diol (or 3-chloro-1,2-propanediol, 3-MCPD) is a well-known food processing contaminant found in a wide range of foods and ingredients. It has been classified as non-genotoxic carcinogen but its carcinogenic potential in the rodents has been controversial. The carcinogenicity to B6C3F1 mice by drinking water administration was assessed over a period of 104 weeks. Three groups, each comprising 50 male and 50 female mice received 3-MCPD at dosages of 30, 100 or 300 ppm up to Day 100 and 200 ppm onward (4.2, 14.3 and 33.0 mg/kg for males; 3.7, 12.2, and 31.0 mg/kg for females), were allocated. Survival was good, with at least 80% of males and 72% of females in each group surviving 104 weeks. Body weights and body weight gain were decreased in males and females receiving 200 ppm. Water and food consumptions of both sexes at 300/200 ppm were lowered. Emaciated or crouching position was observed for animals of both sexes exposed to 200 ppm. There were some differences in hematology and serum biochemistry compared with controls, although there was no histopathological evidence to support those changes. Histopathological examination did not reveal any neoplastic or non-neoplastic findings attributable to treatment with 3-MCPD. It is concluded that drinking water administration of 3-MCPD for 104 weeks revealed no evidence of carcinogenic potential.

  10. A method for computing the inter-residue interaction potentials for ...

    Indian Academy of Sciences (India)

    PRAKASH KUMAR

    2007-06-16

    Jun 16, 2007 ... overview of the methods used to reduce the amino acid alphabet; second, we .... The MDS is a widely used method in social sciences and psychometry ... structures) statistical potential functions is the method of choice for ...

  11. The Differential Proteome of the Probiotic Lactobacillus acidophilus NCFM Grown on the Potential Prebiotic Cellobiose Shows Upregulation of Two beta-Glycoside Hydrolases

    DEFF Research Database (Denmark)

    van Zanten, Gabriella Christina; Sparding, Nadja; Majumder, Avishek

    2015-01-01

    Probiotics, prebiotics, and combinations there of, that is, synbiotics, are known to exert beneficial health effects in humans; however interactions between pro-and prebiotics remain poorly understood at the molecular level. The present study describes changes in abundance of different proteins...... of the probiotic bacterium Lactobacillus acidophilus NCFM (NCFM) when grown on the potential prebiotic cellobiose as compared to glucose. Cytosolic cell extract proteomes after harvest at late exponential phase of NCFM grown on cellobiose or glucose were analyzed by two dimensional difference gel electrophoresis....... Many of these proteins were associated with energy metabolism, including the cellobiose related glycoside hydrolases phospho-β-glucosidase (LBA0881) and phospho-β-galactosidase II (LBA0726). The data provide insight into the utilization of the candidate prebiotic cellobiose by the probiotic bacterium...

  12. A method for evaluating photovoltaic potential in China based on GIS platform

    Science.gov (United States)

    Wang, L. Z.; Tan, H. W.; Ji, L.; Wang, D.

    2017-11-01

    Solar photovoltaic systems are commonly utilized in China. However, the associated research is still lack of its resource potential analysis in all regions in China. Based on the existed data about solar radiation and system conversion efficiency data, a new method for distributed photovoltaic potential assessment has been presented. The experiment of three kinds of solar photovoltaic system has been set up for the purpose of analyzing the relationship between conversion efficiency and environmental parameters. This paper fits the relationship between conversion efficiency and solar radiation intensity. This method takes into account the amount of solar radiation that is effectively generated and drives away the weak values. With the spatial analysis function of geographic information system (GIS) platform, frequency distribution of solar radiation intensity and PV potential in China can be derived. Furthermore, analytical results show that monocrystalline-silicon PV generation in the north-western and northern areas have reached a level of more than 200 kWh/(m2.a), making those areas be suitable for the development of PV system. However, the potential for southwest areas reaches a level of only 130 kWh/(m2.a). This paper can provide the baseline reference for solar energy development planning.

  13. Retinal single-layer analysis with optical coherence tomography shows inner retinal layer thinning in Huntington's disease as a potential biomarker.

    Science.gov (United States)

    Gulmez Sevim, Duygu; Unlu, Metin; Gultekin, Murat; Karaca, Cagatay

    2018-02-12

    There have been ongoing clinical trials of therapeutic agents in Huntington's disease (HD) which requires development of reliable biomarkers of disease progression. There have been studies in the literature with conflicting results on the involvement of retina in HD, and up to date there is not a study evaluating the single retinal layers in HD. We aimed to evaluate the specific retinal changes in HD and their usability as potential disease progression markers. This cross-sectional study used spectral-domain optical coherence tomography with automatic segmentation to measure peripapillary retinal nerve fiber layer (pRNFL) thickness and the thickness and volume of retinal layers in foveal scans of 15 patients with HD and 15 age- and sex-matched controls. Genetic testing results, disease duration, HD disease burden scores and Unified HD Rating Scales motor scores were acquired for the patients. Temporal pRNFL, macular RNFL (mRNFL), ganglion cell layer (GCL), inner plexiform layer (IPL), inner nuclear layer and outer plexiform layer thicknesses and IPL, retinal pigment epithelium and outer macular volume were found lower in HD compared to controls, while outer nuclear layer and outer retinal layer thickness were increased (p layer thicknesses, most significantly with mRNFL and GCL and disease progression markers. The outcomes of this study points out that retinal layers, most significantly mRNFL and GCL, are strongly correlated with the disease progression in HD and could serve as useful biomarkers for disease progression.

  14. Evaluation of the constant potential method in simulating electric double-layer capacitors

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Zhenxing; Laird, Brian B., E-mail: blaird@ku.edu [Department of Chemistry, University of Kansas, Lawrence, Kansas 66045 (United States); Yang, Yang; Olmsted, David L.; Asta, Mark [Department of Materials Science and Engineering, University of California, Berkeley, California 94720 (United States)

    2014-11-14

    A major challenge in the molecular simulation of electric double layer capacitors (EDLCs) is the choice of an appropriate model for the electrode. Typically, in such simulations the electrode surface is modeled using a uniform fixed charge on each of the electrode atoms, which ignores the electrode response to local charge fluctuations in the electrolyte solution. In this work, we evaluate and compare this Fixed Charge Method (FCM) with the more realistic Constant Potential Method (CPM), [S. K. Reed et al., J. Chem. Phys. 126, 084704 (2007)], in which the electrode charges fluctuate in order to maintain constant electric potential in each electrode. For this comparison, we utilize a simplified LiClO{sub 4}-acetonitrile/graphite EDLC. At low potential difference (ΔΨ ⩽ 2 V), the two methods yield essentially identical results for ion and solvent density profiles; however, significant differences appear at higher ΔΨ. At ΔΨ ⩾ 4 V, the CPM ion density profiles show significant enhancement (over FCM) of “inner-sphere adsorbed” Li{sup +} ions very close to the electrode surface. The ability of the CPM electrode to respond to local charge fluctuations in the electrolyte is seen to significantly lower the energy (and barrier) for the approach of Li{sup +} ions to the electrode surface.

  15. Evaluation of the constant potential method in simulating electric double-layer capacitors

    International Nuclear Information System (INIS)

    Wang, Zhenxing; Laird, Brian B.; Yang, Yang; Olmsted, David L.; Asta, Mark

    2014-01-01

    A major challenge in the molecular simulation of electric double layer capacitors (EDLCs) is the choice of an appropriate model for the electrode. Typically, in such simulations the electrode surface is modeled using a uniform fixed charge on each of the electrode atoms, which ignores the electrode response to local charge fluctuations in the electrolyte solution. In this work, we evaluate and compare this Fixed Charge Method (FCM) with the more realistic Constant Potential Method (CPM), [S. K. Reed et al., J. Chem. Phys. 126, 084704 (2007)], in which the electrode charges fluctuate in order to maintain constant electric potential in each electrode. For this comparison, we utilize a simplified LiClO 4 -acetonitrile/graphite EDLC. At low potential difference (ΔΨ ⩽ 2 V), the two methods yield essentially identical results for ion and solvent density profiles; however, significant differences appear at higher ΔΨ. At ΔΨ ⩾ 4 V, the CPM ion density profiles show significant enhancement (over FCM) of “inner-sphere adsorbed” Li + ions very close to the electrode surface. The ability of the CPM electrode to respond to local charge fluctuations in the electrolyte is seen to significantly lower the energy (and barrier) for the approach of Li + ions to the electrode surface

  16. Macrocyclic receptor showing extremely high Sr(II)/Ca(II) and Pb(II)/Ca(II) selectivities with potential application in chelation treatment of metal intoxication.

    Science.gov (United States)

    Ferreirós-Martínez, Raquel; Esteban-Gómez, David; Tóth, Éva; de Blas, Andrés; Platas-Iglesias, Carlos; Rodríguez-Blas, Teresa

    2011-04-18

    Herein we report a detailed investigation of the complexation properties of the macrocyclic decadentate receptor N,N'-Bis[(6-carboxy-2-pyridil)methyl]-4,13-diaza-18-crown-6 (H(2)bp18c6) toward different divalent metal ions [Zn(II), Cd(II), Pb(II), Sr(II), and Ca(II)] in aqueous solution. We have found that this ligand is especially suited for the complexation of large metal ions such as Sr(II) and Pb(II), which results in very high Pb(II)/Ca(II) and Pb(II)/Zn(II) selectivities (in fact, higher than those found for ligands widely used for the treatment of lead poisoning such as ethylenediaminetetraacetic acid (edta)), as well as in the highest Sr(II)/Ca(II) selectivity reported so far. These results have been rationalized on the basis of the structure of the complexes. X-ray crystal diffraction, (1)H and (13)C NMR spectroscopy, as well as theoretical calculations at the density functional theory (B3LYP) level have been performed. Our results indicate that for large metal ions such as Pb(II) and Sr(II) the most stable conformation is Δ(δλδ)(δλδ), while for Ca(II) our calculations predict the Δ(λδλ)(λδλ) form being the most stable one. The selectivity that bp18c6(2-) shows for Sr(II) over Ca(II) can be attributed to a better fit between the large Sr(II) ions and the relatively large crown fragment of the ligand. The X-ray crystal structure of the Pb(II) complex shows that the Δ(δλδ)(δλδ) conformation observed in solution is also maintained in the solid state. The Pb(II) ion is endocyclically coordinated, being directly bound to the 10 donor atoms of the ligand. The bond distances to the donor atoms of the pendant arms (2.55-2.60 Å) are substantially shorter than those between the metal ion and the donor atoms of the crown moiety (2.92-3.04 Å). This is a typical situation observed for the so-called hemidirected compounds, in which the Pb(II) lone pair is stereochemically active. The X-ray structures of the Zn(II) and Cd(II) complexes show that

  17. Landslide potential zonation in Baleghlu watershed (NW Iran) using AHP Fuzzy method

    Science.gov (United States)

    Jananeh, Keristineh; Roostai, Shahram

    2017-04-01

    Landslides and slope instabilities are among the important natural hazards, which cause human and financial casualties and loss of economic resources every year. These hazards mostly occur in natural slopes or those manipulated by human. Zonation of areas with regard to landslide potential is one of the means to identify areas prone to produce landslide and so, to conduct plannings and management based on the prepared zonation maps in order to reduce the casualties. This contribution investigates on the landslide potential zonation within the Baleghlu watershed. This watershed is located in the southeast of Sabalan volcano (NW Iran) within the longitudes of 47° 48` and 48° 12` E and northern latitudes of 37° 51` and 38° 16` N. Its main river is Baleghlu, which is later connected to the Arax river through the Qarasu and Dareh Roud rivers, and is finally terminated to the Caspian sea. The method of investigation is Fuzzy AHP in the GIS environment. First, the main factors including the slope and its direction, geology, soil, climate, distance from the road and river and land usage were investigated and then, after preparing data layers based on the above-mentioned parameters and giving weights to them in the GIS environment, the landslide potential map was prepared by Fuzzy AHP method. It was revealed that the slope factor with the value of 0.3882 has the highest weight, while the land usage factor with the value of 0.0287 has the lowest weight. According to the final zonation map of the landslide potential, the watershed was divided into 5 classes, ranging from very high potential class to the very low potential. The obtained results showed that the largest part of the watershed (32.21%) has low landslide potential, while about 13.5% of it has very high potential. Areas with very high and high landslide potential (327.39 km2 area) are mainly located in the northwest of the watershed, with some small areas distributed in the south and east, while areas with very

  18. Comparison of potential method in analytic hierarchy process for multi-attribute of catering service companies

    Science.gov (United States)

    Mamat, Siti Salwana; Ahmad, Tahir; Awang, Siti Rahmah

    2017-08-01

    Analytic Hierarchy Process (AHP) is a method used in structuring, measuring and synthesizing criteria, in particular ranking of multiple criteria in decision making problems. On the other hand, Potential Method is a ranking procedure in which utilizes preference graph ς (V, A). Two nodes are adjacent if they are compared in a pairwise comparison whereby the assigned arc is oriented towards the more preferred node. In this paper Potential Method is used to solve problem on a catering service selection. The comparison of result by using Potential method is made with Extent Analysis. The Potential Method is found to produce the same rank as Extent Analysis in AHP.

  19. Non-Water-Suppressed 1H MR Spectroscopy with Orientational Prior Knowledge Shows Potential for Separating Intra- and Extramyocellular Lipid Signals in Human Myocardium.

    Science.gov (United States)

    Fillmer, Ariane; Hock, Andreas; Cameron, Donnie; Henning, Anke

    2017-12-04

    Conditions such as type II diabetes are linked with elevated lipid levels in the heart, and significantly increased risk of heart failure; however, metabolic processes underlying the development of cardiac disease in type II diabetes are not fully understood. Here we present a non-invasive method for in vivo investigation of cardiac lipid metabolism: namely, IVS-McPRESS. This technique uses metabolite-cycled, non-water suppressed 1 H cardiac magnetic resonance spectroscopy with prospective and retrospective motion correction. High-quality IVS-McPRESS data acquired from healthy volunteers allowed us to investigate the frequency shift of extramyocellular lipid signals, which depends on the myocardial fibre orientation. Assuming consistent voxel positioning relative to myofibres, the myofibre angle with the magnetic field was derived from the voxel orientation. For separation and individual analysis of intra- and extramyocellular lipid signals, the angle myocardial fibres in the spectroscopy voxel take with the magnetic field should be within ±24.5°. Metabolite and lipid concentrations were analysed with respect to BMI. Significant correlations between BMI and unsaturated fatty acids in intramyocellular lipids, and methylene groups in extramyocellular lipids were found. The proposed IVS-McPRESS technique enables non-invasive investigation of cardiac lipid metabolism and may thus be a useful tool to study healthy and pathological conditions.

  20. Program impact pathway analysis of a social franchise model shows potential to improve infant and young child feeding practices in Vietnam.

    Science.gov (United States)

    Nguyen, Phuong H; Menon, Purnima; Keithly, Sarah C; Kim, Sunny S; Hajeebhoy, Nemat; Tran, Lan M; Ruel, Marie T; Rawat, Rahul

    2014-10-01

    By mapping the mechanisms through which interventions are expected to achieve impact, program impact pathway (PIP) analysis lays out the theoretical causal links between program activities, outcomes, and impacts. This study examines the pathways through which the Alive & Thrive (A&T) social franchise model is intended to improve infant and young child feeding (IYCF) practices in Vietnam. Mixed methods were used, including qualitative interviews with franchise management board members (n = 12), surveys with health providers (n = 120), counseling observations (n = 160), and household surveys (n = 2045). Six PIP components were assessed: 1) franchise management, 2) training and IYCF knowledge of health providers, 3) service delivery, 4) program exposure and utilization, 5) maternal behavioral determinants (knowledge, beliefs, and intentions) toward optimal IYCF practices, and 6) IYCF practices. Data were collected from A&T-intensive areas (A&T-I; mass media + social franchise) and A&T-nonintensive areas (A&T-NI; mass media only) by using a cluster-randomized controlled trial design. Data from 2013 were compared with baseline where similar measures were available. Results indicate that mechanisms are in place for effective management of the franchise system, despite challenges to routine monitoring. A&T training was associated with increased capacity of providers, resulting in higher-quality IYCF counseling (greater technical knowledge and communication skills during counseling) in A&T-I areas. Franchise utilization increased from 10% in 2012 to 45% in 2013 but fell below the expected frequency of 9-15 contacts per mother-child dyad. Improvements in breastfeeding knowledge, beliefs, intentions, and practices were greater among mothers in A&T-I areas than among those in A&T-NI areas. In conclusion, there are many positive changes along the impact pathway of the franchise services, but challenges in utilization and demand creation should be addressed to achieve the full

  1. [Estimation of Topsoil Carbon Sequestration Potential of Cropland Through Different Methods: A Case Study in Zhuanglang County, Gansu Province].

    Science.gov (United States)

    Shi, Chen-di; Xu, Ming-xiang; Qiu, Yu-jie

    2016-03-15

    By analyzing the sampled data and the SOC data of the second national soil survey by the mid 80s and the national cultivated land quality evaluation in 2006 in Zhuanglang County, the article studied the cropland topsoil organic carbon sequestration potential estimation using several different methods. The results showed that: (1) There was no significant difference among different estimation methods about cropland carbon sequestration potential in the same region. Taking cropland carbon sequestration potential in Zhuanglang County for example, the theoretical values estimated by maximum value method and classification grading method were 1. 13 Mt and 1.09 Mt, respectively. (2) The real values estimated by classification grading method, saturation method, weighting method were 0.37 Mt, 0.32 Mt, 0.28 Mt, respectively, which were about 1/3 of the theoretical value. (3) The SOC density increments to reach the real level of carbon sequestration potential estimated by classification grading method, saturation method and weighting method were 6.76 t · hm⁻², 5.21 t · hm⁻², 4.56 t · hm⁻² respectively. According to the topsoil carbon sequestration rate of cropland in Zhuanglang county in the recent 30 a, it would need about 24-34 a to achieve the real level. (4) At the county scale, the weighted method was superior to the saturation value method, and the saturation value method was better than the classification grading method in the actual carbon sequestration potential estimation. The classification grading method was better than the maximum value method in the ideal carbon sequestration potential estimation.

  2. Adolescent C57BL/6J mice show elevated alcohol intake, but reduced taste aversion, as compared to adult mice: a potential behavioral mechanism for binge drinking.

    Science.gov (United States)

    Holstein, Sarah E; Spanos, Marina; Hodge, Clyde W

    2011-10-01

    Binge alcohol drinking during adolescence is a serious health problem that may increase future risk of an alcohol use disorder. Although there are several different procedures by which to preclinically model binge-like alcohol intake, limited-access procedures offer the advantage of achieving high voluntary alcohol intake and pharmacologically relevant blood alcohol concentrations (BACs). Therefore, in the current study, developmental differences in binge-like alcohol drinking using a limited-access cycling procedure were examined. In addition, as alcohol drinking has been negatively correlated with sensitivity to the aversive properties of alcohol, we examined developmental differences in sensitivity to an alcohol-induced conditioned taste aversion (CTA). Binge-like alcohol consumption was investigated in adolescent (4 weeks) and adult (10 weeks) male C57BL/6J mice for 2 to 4 h/d for 16 days. Developmental differences in sensitivity to an alcohol-induced CTA were examined in adolescent and adult mice, with saline or alcohol (3 or 4 g/kg) repeatedly paired with the intake of a novel tastant (NaCl). Adolescent mice showed a significant increase in alcohol intake as compared to adults, with adolescents achieving higher BACs and increasing alcohol consumption over successive cycles of the binge procedure. Conversely, adolescent mice exhibited a dose-dependent reduction in sensitivity to the aversive properties of alcohol, as compared to adult mice, with adolescent mice failing to develop a CTA to 3 g/kg alcohol. Finally, extinction of an alcohol CTA was observed following conditioning with a higher dose of alcohol in adolescent, versus adult, mice. These results indicate that adolescent mice consume more alcohol, per kilogram body weight, than adults in a binge-like model of alcohol drinking and demonstrate a blunted sensitivity to the conditioned aversive effects of alcohol. Overall, this supports a behavioral framework by which heightened binge alcohol intake during

  3. A New Method for Obtaining the Baryons Mass under the Killingbeck Plus Isotonic Oscillator Potentials

    Directory of Open Access Journals (Sweden)

    Nasrin Salehi

    2016-01-01

    Full Text Available The spectrum of ground state and excited baryons (N, Δ, Λ, Σ, Ξ, and Ω particles has been investigated by using nonrelativistic quantum mechanics under the Killingbeck plus isotonic oscillator potentials. Using the Jacobi coordinates, anzast method, and generalized Gürsey Radicati (GR mass formula the three-body-wave equation is solved to calculate the different states of the considered baryons. A comparison between our calculations and the available experimental data shows that the position of the Roper resonances of the nucleon, the ground states, and the excited multiplets up to three GeV are in general well reproduced. Also one can conclude that the interaction between the quark constituents of baryon resonances could be described adequately by using the combination of Killingbeck and isotonic oscillator potentials form.

  4. An accurate method for the determination of unlike potential parameters from thermal diffusion data

    International Nuclear Information System (INIS)

    El-Geubeily, S.

    1997-01-01

    A new method is introduced by means of which the unlike intermolecular potential parameters can be determined from the experimental measurements of the thermal diffusion factor as a function of temperature. The method proved to be easy, accurate, and applicable two-, three-, and four-parameter potential functions whose collision integrals are available. The potential parameters computed by this method are found to provide a faith full representation of the thermal diffusion data under consideration. 3 figs., 4 tabs

  5. A transfer matrix method for the analysis of fractal quantum potentials

    International Nuclear Information System (INIS)

    Monsoriu, Juan A; Villatoro, Francisco R; Marin, Maria J; UrchueguIa, Javier F; Cordoba, Pedro Fernandez de

    2005-01-01

    The scattering properties of quantum particles on a sequence of potentials converging towards a fractal one are obtained by means of the transfer matrix method. The reflection coefficients for both the fractal potential and finite periodic potential are calculated and compared. It is shown that the reflection coefficient for the fractal potential has a self-similar structure associated with the fractal distribution of the potential whose degree of self-similarity has been quantified by means of the correlation function

  6. A transfer matrix method for the analysis of fractal quantum potentials

    Energy Technology Data Exchange (ETDEWEB)

    Monsoriu, Juan A [Departamento de Fisica Aplicada, Universidad Politecnica de Valencia, E-46022 Valencia (Spain); Villatoro, Francisco R [Departamento de Lenguajes y Ciencias de la Computacion, Universidad de Malaga, E-29071 Malaga (Spain); Marin, Maria J [Departamento de Termodinamica, Universitat de Valencia, E-46100 Burjassot (Spain); UrchueguIa, Javier F [Departamento de Fisica Aplicada, Universidad Politecnica de Valencia, E-46022 Valencia (Spain); Cordoba, Pedro Fernandez de [Departamento de Matematica Aplicada, Universidad Politecnica de Valencia, E-46022 Valencia (Spain)

    2005-07-01

    The scattering properties of quantum particles on a sequence of potentials converging towards a fractal one are obtained by means of the transfer matrix method. The reflection coefficients for both the fractal potential and finite periodic potential are calculated and compared. It is shown that the reflection coefficient for the fractal potential has a self-similar structure associated with the fractal distribution of the potential whose degree of self-similarity has been quantified by means of the correlation function.

  7. Validation and Recommendation of Methods to Measure Biogas Production Potential of Animal Manure

    Directory of Open Access Journals (Sweden)

    C. H. Pham

    2013-06-01

    Full Text Available In developing countries, biogas energy production is seen as a technology that can provide clean energy in poor regions and reduce pollution caused by animal manure. Laboratories in these countries have little access to advanced gas measuring equipment, which may limit research aimed at improving local adapted biogas production. They may also be unable to produce valid estimates of an international standard that can be used for articles published in international peer-reviewed science journals. This study tested and validated methods for measuring total biogas and methane (CH4 production using batch fermentation and for characterizing the biomass. The biochemical methane potential (BMP (CH4 NL kg−1 VS of pig manure, cow manure and cellulose determined with the Moller and VDI methods was not significantly different in this test (p>0.05. The biodegradability using a ratio of BMP and theoretical BMP (TBMP was slightly higher using the Hansen method, but differences were not significant. Degradation rate assessed by methane formation rate showed wide variation within the batch method tested. The first-order kinetics constant k for the cumulative methane production curve was highest when two animal manures were fermented using the VDI 4630 method, indicating that this method was able to reach steady conditions in a shorter time, reducing fermentation duration. In precision tests, the repeatability of the relative standard deviation (RSDr for all batch methods was very low (4.8 to 8.1%, while the reproducibility of the relative standard deviation (RSDR varied widely, from 7.3 to 19.8%. In determination of biomethane concentration, the values obtained using the liquid replacement method (LRM were comparable to those obtained using gas chromatography (GC. This indicates that the LRM method could be used to determine biomethane concentration in biogas in laboratories with limited access to GC.

  8. Study of Monte Carlo Simulation Method for Methane Phase Diagram Prediction using Two Different Potential Models

    KAUST Repository

    Kadoura, Ahmad

    2011-06-06

    Lennard‐Jones (L‐J) and Buckingham exponential‐6 (exp‐6) potential models were used to produce isotherms for methane at temperatures below and above critical one. Molecular simulation approach, particularly Monte Carlo simulations, were employed to create these isotherms working with both canonical and Gibbs ensembles. Experiments in canonical ensemble with each model were conducted to estimate pressures at a range of temperatures above methane critical temperature. Results were collected and compared to experimental data existing in literature; both models showed an elegant agreement with the experimental data. In parallel, experiments below critical temperature were run in Gibbs ensemble using L‐J model only. Upon comparing results with experimental ones, a good fit was obtained with small deviations. The work was further developed by adding some statistical studies in order to achieve better understanding and interpretation to the estimated quantities by the simulation. Methane phase diagrams were successfully reproduced by an efficient molecular simulation technique with different potential models. This relatively simple demonstration shows how powerful molecular simulation methods could be, hence further applications on more complicated systems are considered. Prediction of phase behavior of elemental sulfur in sour natural gases has been an interesting and challenging field in oil and gas industry. Determination of elemental sulfur solubility conditions helps avoiding all kinds of problems caused by its dissolution in gas production and transportation processes. For this purpose, further enhancement to the methods used is to be considered in order to successfully simulate elemental sulfur phase behavior in sour natural gases mixtures.

  9. A comparison of genotyping-by-sequencing analysis methods on low-coverage crop datasets shows advantages of a new workflow, GB-eaSy.

    Science.gov (United States)

    Wickland, Daniel P; Battu, Gopal; Hudson, Karen A; Diers, Brian W; Hudson, Matthew E

    2017-12-28

    Genotyping-by-sequencing (GBS), a method to identify genetic variants and quickly genotype samples, reduces genome complexity by using restriction enzymes to divide the genome into fragments whose ends are sequenced on short-read sequencing platforms. While cost-effective, this method produces extensive missing data and requires complex bioinformatics analysis. GBS is most commonly used on crop plant genomes, and because crop plants have highly variable ploidy and repeat content, the performance of GBS analysis software can vary by target organism. Here we focus our analysis on soybean, a polyploid crop with a highly duplicated genome, relatively little public GBS data and few dedicated tools. We compared the performance of five GBS pipelines using low-coverage Illumina sequence data from three soybean populations. To address issues identified with existing methods, we developed GB-eaSy, a GBS bioinformatics workflow that incorporates widely used genomics tools, parallelization and automation to increase the accuracy and accessibility of GBS data analysis. Compared to other GBS pipelines, GB-eaSy rapidly and accurately identified the greatest number of SNPs, with SNP calls closely concordant with whole-genome sequencing of selected lines. Across all five GBS analysis platforms, SNP calls showed unexpectedly low convergence but generally high accuracy, indicating that the workflows arrived at largely complementary sets of valid SNP calls on the low-coverage data analyzed. We show that GB-eaSy is approximately as good as, or better than, other leading software solutions in the accuracy, yield and missing data fraction of variant calling, as tested on low-coverage genomic data from soybean. It also performs well relative to other solutions in terms of the run time and disk space required. In addition, GB-eaSy is built from existing open-source, modular software packages that are regularly updated and commonly used, making it straightforward to install and maintain

  10. Advances in developing a new test method to assess spray drift potential from air blast sprayers

    Energy Technology Data Exchange (ETDEWEB)

    Grella, M.; Gil, E.; Balsari, P.; Marucco, P.; Gallart, M.

    2017-07-01

    Drift is one of the most important issues to consider for realising sustainable pesticide sprays. This study proposes and tests an alternative methodology for quantifying the drift potential (DP) of air blast sprayers, trying to avoid the difficulties faced in conducting field trials according to the standard protocol (ISO 22866:2005). For this purpose, an ad hoc test bench designed for DP comparative measurements was used. The proposed methodology was evaluated in terms of robustness, repetitiveness and coherence by arranging a series of trials at two laboratories. Representative orchard and vineyard air blast sprayers in eight configurations (combination of two forward speeds, two air fan flow rates, and two nozzle types) were tested. The test bench was placed perpendicular to the spray track to collect the fraction of spray liquid remaining in the air after the spray process and potentially susceptible to drift out of the treated area. Downwind spray deposition curves were obtained and a new approach was proposed to calculate an index value of the DP estimation that could allow the differences among the tested configurations to be described. Results indicated that forward speed of 1.67 m/s allows better discrimination among configurations tested. Highest DP reduction, over 87.5%, was achieved using the TVI nozzles in combination with low air fan flow rate in both laboratories; conversely, the highest DP value was obtained with the ATR nozzles in combination with high air fan flow rate. Although the proposed method shows a promising potential to evaluate drift potential of different sprayer types and nozzles types used for bush and tree crops further research and tests are necessary to improve and validate this method.

  11. Detailed balance method for chemical potential determination in Monte Carlo and molecular dynamics simulations

    International Nuclear Information System (INIS)

    Fay, P.J.; Ray, J.R.; Wolf, R.J.

    1994-01-01

    We present a new, nondestructive, method for determining chemical potentials in Monte Carlo and molecular dynamics simulations. The method estimates a value for the chemical potential such that one has a balance between fictitious successful creation and destruction trials in which the Monte Carlo method is used to determine success or failure of the creation/destruction attempts; we thus call the method a detailed balance method. The method allows one to obtain estimates of the chemical potential for a given species in any closed ensemble simulation; the closed ensemble is paired with a ''natural'' open ensemble for the purpose of obtaining creation and destruction probabilities. We present results for the Lennard-Jones system and also for an embedded atom model of liquid palladium, and compare to previous results in the literature for these two systems. We are able to obtain an accurate estimate of the chemical potential for the Lennard-Jones system at higher densities than reported in the literature

  12. The Application of 2-D Resistivity and Self Potential (SP) Methods in Determining the Water Flow

    Science.gov (United States)

    Nordiana, M. M.; Tajudeen Olugbenga, Adeeko; Afiq Saharudin, Muhamad; nabila, S.; El Hidayah Ismail, Noer

    2018-04-01

    Existence of water flow at urban area will decrease the shear strength and increase hydraulic conductivity of soil which finally caused subsurface problems at this area. To avoid landslide, slope instability and disturbance of the ecosystem, good and detailed planning must be done when developing hilly area. The understanding about geological condition has to be considering before construction activities be done. Six 2-D resistivity survey lines with minimum 5 m electrode spacing were executed using Pole-dipole array. The field investigation such as borehole was carried out at multiple locations in the area where the 2-D resistivity method have been conducted. The directions and intensities of the water were evaluated with self-potential (SP) method. Subsequently, the results from borehole were used to verify the results of electrical resistivity method. Interpretation of 2-D resistivity data showed a low resistivity value (ohm-m), which appears to be a zone that is fully saturated with sandy silt and this could be an influence factor the increasing water level because sandy silt is highly permeable in nature. The borehole, support the results of 2-D resistivity method relating a saturated zone in the survey area. There is a good correlation between the 2-D resistivity investigations and the results of borehole records.

  13. A MISO-ARX-Based Method for Single-Trial Evoked Potential Extraction

    Directory of Open Access Journals (Sweden)

    Nannan Yu

    2017-01-01

    Full Text Available In this paper, we propose a novel method for solving the single-trial evoked potential (EP estimation problem. In this method, the single-trial EP is considered as a complex containing many components, which may originate from different functional brain sites; these components can be distinguished according to their respective latencies and amplitudes and are extracted simultaneously by multiple-input single-output autoregressive modeling with exogenous input (MISO-ARX. The extraction process is performed in three stages: first, we use a reference EP as a template and decompose it into a set of components, which serve as subtemplates for the remaining steps. Then, a dictionary is constructed with these subtemplates, and EPs are preliminarily extracted by sparse coding in order to roughly estimate the latency of each component. Finally, the single-trial measurement is parametrically modeled by MISO-ARX while characterizing spontaneous electroencephalographic activity as an autoregression model driven by white noise and with each component of the EP modeled by autoregressive-moving-average filtering of the subtemplates. Once optimized, all components of the EP can be extracted. Compared with ARX, our method has greater tracking capabilities of specific components of the EP complex as each component is modeled individually in MISO-ARX. We provide exhaustive experimental results to show the effectiveness and feasibility of our method.

  14. Monitoring underground migration of sequestered CO2 using self-potential methods

    Science.gov (United States)

    Ishido, T.; Pritchett, J.; Tosha, T.; Nishi, Y.; Nakanishi, S.

    2013-12-01

    An appropriate monitoring program is indispensable for an individual geologic storage project to aid in answering various operational questions by detecting changes within the reservoir and to provide early warning of potential CO2 leakage through the caprock. Such a program is also essential to reduce uncertainties associated with reservoir parameters and to improve the predictive capability of reservoir models. Repeat geophysical measurements performed at the earth surface show particular promise for monitoring large subsurface volumes. To appraise the utility of geophysical techniques, Ishido et al. carried out numerical simulations of an aquifer system underlying a portion of Tokyo Bay and calculated the temporal changes in geophysical observables caused by changing underground conditions as computed by reservoir simulation (Energy Procedia, 2011). They used 'geophysical postprocessors' to calculate the resulting temporal changes in the earth-surface distributions of microgravity, self-potential (SP), apparent resistivity (from MT surveys) and seismic observables. The applicability of any particular method is likely to be highly site-specific, but these calculations indicate that none of these techniques should be ruled out altogether. Some survey techniques (gravity, MT resistivity) appear to be suitable for characterizing long-term changes, whereas others (seismic reflection, SP) are quite responsive to short term disturbances. The self-potential postprocessor calculates changes in subsurface electrical potential induced by pressure disturbances through electrokinetic coupling (Ishido & Pritchett, JGR 1999). In addition to electrokinetic coupling, SP anomalies may be generated by various other mechanisms such as thermoelectric coupling, electrochemical diffusion potential, etc. In particular, SP anomalies of negative polarity, which are frequently observed near wells, appear to be caused by an underground electrochemical mechanism similar to a galvanic cell

  15. The Electrical Self-Potential Method as a Non-Intrusive Snow-Hydrological Sensor

    Science.gov (United States)

    Kulessa, B.; Thompson, S. S.; Luethi, M. P.; Essery, R.

    2015-12-01

    Building on growing momentum in the application of geophysical techniques to snow problems and, specifically, on new theory and an electrical geophysical snow hydrological model published recently; we demonstrate for the first time that the electrical self-potential geophysical technique can sense in-situ bulk meltwater fluxes. This has broad and immediate implications for snow measurement practice, modelling and operational snow forecasting. Our ability to measure, quantify and assimilate hydrological properties and processes of snow in operational models is disproportionally poor compared to the significance of seasonal snowmelt as a global water resource and major risk factor in flood and avalanche forecasting. Encouraged by recent theoretical, modelling and laboratory work, we show here that the diurnal evolution of aerially-distributed self-potential magnitudes closely track those of bulk meltwater fluxes in melting in-situ snowpacks at Rhone and Jungfraujoch glaciers, Switzerland. Numerical modelling infers temporally-evolving liquid water contents in the snowpacks on successive days in close agreement with snow-pit measurements. Muting previous concerns, the governing physical and chemical properties of snow and meltwater became temporally invariant for modelling purposes. Because measurement procedure is straightforward and readily automated for continuous monitoring over significant spatial scales, we conclude that the self-potential geophysical method is a highly-promising non-intrusive snow-hydrological sensor for measurement practice, modelling and operational snow forecasting.

  16. Control Systems for Hyper-Redundant Robots Based on Artificial Potential Method

    Directory of Open Access Journals (Sweden)

    Mihaela Florescu

    2015-06-01

    Full Text Available This paper presents the control method of hyper-redundant robots based on the artificial potential approach. The principles of this method are shown and a suggestive example is offered. Then, the artificial potential method is applied to the case of a tentacle robot starting from the dynamic model of the robot. In addition, a series of results that are obtained through simulation is presented.

  17. Groundwater potential prediction by using geoelectricity method a case study in Simpang Lima and around it

    Science.gov (United States)

    Rahmawati, D. R.; Supriyadi; Aryani, N. P.; Naufal, M. A.

    2018-03-01

    Water is an important natural resource, which is available both on surface as well as in recharge zone of weathered layer and in various other suitable water reservoir formations/structures below the surface. The study was conducted in Semarang City, Indonesian. Simpang Lima area were chosen since they have geology record of thick alluvium. The condition of Simpang Lima and around it which currently has developed into the main business area in Semarang City. This is marked by the presence like hotels, super market, that is more than one. This condition certainly requires a supply of water for various purposes that support economic efforts in the region. During this time the water needs are met by drilling wells and used as much as possible without taking into account the impact of water utilization. This study aims to determine the zones that have the potential existence of groundwater. The method used is Geoelectric method with Shlumberger configuration in 7 distributed spatial point. The results showed that there is a potential groundwater in eastern Pekunden, Erlanga, behind The Hotel Horizon, and Simpang Lima. Groundwater is found successively at an average depth of 15 meters under earth’s surface.

  18. A Two-Stage Method to Determine Optimal Product Sampling considering Dynamic Potential Market

    Science.gov (United States)

    Hu, Zhineng; Lu, Wei; Han, Bing

    2015-01-01

    This paper develops an optimization model for the diffusion effects of free samples under dynamic changes in potential market based on the characteristics of independent product and presents a two-stage method to figure out the sampling level. The impact analysis of the key factors on the sampling level shows that the increase of the external coefficient or internal coefficient has a negative influence on the sampling level. And the changing rate of the potential market has no significant influence on the sampling level whereas the repeat purchase has a positive one. Using logistic analysis and regression analysis, the global sensitivity analysis gives a whole analysis of the interaction of all parameters, which provides a two-stage method to estimate the impact of the relevant parameters in the case of inaccuracy of the parameters and to be able to construct a 95% confidence interval for the predicted sampling level. Finally, the paper provides the operational steps to improve the accuracy of the parameter estimation and an innovational way to estimate the sampling level. PMID:25821847

  19. Evaluation of in vitro antioxidant potential of different polarities stem crude extracts by different extraction methods of Adenium obesum

    Directory of Open Access Journals (Sweden)

    Mohammad Amzad Hossain

    2014-09-01

    Full Text Available Objective: To select best extraction method for the isolated antioxidant compounds from the stems of Adenium obesum. Methods: Two methods used for the extraction are Soxhlet and maceration methods. Methanol solvent was used for both extraction method. The methanol crude extract was defatted with water and extracted successively with hexane, chloroform, ethyl acetate and butanol solvents. The antioxidant potential for all crude extracts were determined by using 1, 1-diphenyl-2- picrylhydrazyl method. Results: The percentage of extraction yield by Soxhlet method is higher compared to maceration method. The antioxidant potential for methanol and its derived fractions by Soxhlet extractor method was highest in ethyl acetate and lowest in hexane crude extracts and found in the order of ethyl acetate>butanol>water>chloroform>methanol>hexane. However, the antioxidant potential for methanol and its derived fractions by maceration method was highest in butanol and lowest in hexane followed in the order of butanol>methanol>chloroform>water>ethyl acetate>hexane. Conclusions: The results showed that isolate antioxidant compounds effected on the extraction method and condition of extraction.

  20. A simple method for analyzing exome sequencing data shows distinct levels of nonsynonymous variation for human immune and nervous system genes.

    Directory of Open Access Journals (Sweden)

    Jan Freudenberg

    Full Text Available To measure the strength of natural selection that acts upon single nucleotide variants (SNVs in a set of human genes, we calculate the ratio between nonsynonymous SNVs (nsSNVs per nonsynonymous site and synonymous SNVs (sSNVs per synonymous site. We transform this ratio with a respective factor f that corrects for the bias of synonymous sites towards transitions in the genetic code and different mutation rates for transitions and transversions. This method approximates the relative density of nsSNVs (rdnsv in comparison with the neutral expectation as inferred from the density of sSNVs. Using SNVs from a diploid genome and 200 exomes, we apply our method to immune system genes (ISGs, nervous system genes (NSGs, randomly sampled genes (RSGs, and gene ontology annotated genes. The estimate of rdnsv in an individual exome is around 20% for NSGs and 30-40% for ISGs and RSGs. This smaller rdnsv of NSGs indicates overall stronger purifying selection. To quantify the relative shift of nsSNVs towards rare variants, we next fit a linear regression model to the estimates of rdnsv over different SNV allele frequency bins. The obtained regression models show a negative slope for NSGs, ISGs and RSGs, supporting an influence of purifying selection on the frequency spectrum of segregating nsSNVs. The y-intercept of the model predicts rdnsv for an allele frequency close to 0. This parameter can be interpreted as the proportion of nonsynonymous sites where mutations are tolerated to segregate with an allele frequency notably greater than 0 in the population, given the performed normalization of the observed nsSNV to sSNV ratio. A smaller y-intercept is displayed by NSGs, indicating more nonsynonymous sites under strong negative selection. This predicts more monogenically inherited or de-novo mutation diseases that affect the nervous system.

  1. Cell wall proteome of sugarcane stems: comparison of a destructive and a non-destructive extraction method showed differences in glycoside hydrolases and peroxidases.

    Science.gov (United States)

    Calderan-Rodrigues, Maria Juliana; Jamet, Elisabeth; Douché, Thibaut; Bonassi, Maria Beatriz Rodrigues; Cataldi, Thaís Regiani; Fonseca, Juliana Guimarães; San Clemente, Hélène; Pont-Lezica, Rafael; Labate, Carlos Alberto

    2016-01-11

    Sugarcane has been used as the main crop for ethanol production for more than 40 years in Brazil. Recently, the production of bioethanol from bagasse and straw, also called second generation (2G) ethanol, became a reality with the first commercial plants started in the USA and Brazil. However, the industrial processes still need to be improved to generate a low cost fuel. One possibility is the remodeling of cell walls, by means of genetic improvement or transgenesis, in order to make the bagasse more accessible to hydrolytic enzymes. We aimed at characterizing the cell wall proteome of young sugarcane culms, to identify proteins involved in cell wall biogenesis. Proteins were extracted from the cell walls of 2-month-old culms using two protocols, non-destructive by vacuum infiltration vs destructive. The proteins were identified by mass spectrometry and bioinformatics. A predicted signal peptide was found in 84 different proteins, called cell wall proteins (CWPs). As expected, the non-destructive method showed a lower percentage of proteins predicted to be intracellular than the destructive one (33% vs 44%). About 19% of CWPs were identified with both methods, whilst the infiltration protocol could lead to the identification of 75% more CWPs. In both cases, the most populated protein functional classes were those of proteins related to lipid metabolism and oxido-reductases. Curiously, a single glycoside hydrolase (GH) was identified using the non-destructive method whereas 10 GHs were found with the destructive one. Quantitative data analysis allowed the identification of the most abundant proteins. The results highlighted the importance of using different protocols to extract proteins from cell walls to expand the coverage of the cell wall proteome. Ten GHs were indicated as possible targets for further studies in order to obtain cell walls less recalcitrant to deconstruction. Therefore, this work contributed to two goals: enlarge the coverage of the sugarcane

  2. The Sturmian expansion: A well-depth-method for orbitals in a deformed potential

    International Nuclear Information System (INIS)

    Bang, J.M.; Vaagen, J.S.

    1980-01-01

    The Sturmian expansion method has over the years successfully been used to generate orbitals in a deformed potential. In this paper we review the method in detail including more recent extentions. The convergence properties are discussed in terms of examples of current interest for nucleon-transfer reactions. Comparisons with other methods are also made. (orig.)

  3. An efficient and accurate method to obtain the energy-dependent Green function for general potentials

    International Nuclear Information System (INIS)

    Kramer, T; Heller, E J; Parrott, R E

    2008-01-01

    Time-dependent quantum mechanics provides an intuitive picture of particle propagation in external fields. Semiclassical methods link the classical trajectories of particles with their quantum mechanical propagation. Many analytical results and a variety of numerical methods have been developed to solve the time-dependent Schroedinger equation. The time-dependent methods work for nearly arbitrarily shaped potentials, including sources and sinks via complex-valued potentials. Many quantities are measured at fixed energy, which is seemingly not well suited for a time-dependent formulation. Very few methods exist to obtain the energy-dependent Green function for complicated potentials without resorting to ensemble averages or using certain lead-in arrangements. Here, we demonstrate in detail a time-dependent approach, which can accurately and effectively construct the energy-dependent Green function for very general potentials. The applications of the method are numerous, including chemical, mesoscopic, and atomic physics

  4. Re-passivation Potential of Alloy 22 in Chloride plus Nitrate Solutions using the Potentiodynamic-Galvano-static-Potentiostatic Method

    International Nuclear Information System (INIS)

    Evans, Kenneth J.; Rebak, Raul B.

    2007-01-01

    In general, the susceptibility of Alloy 22 to suffer crevice corrosion is measured using the Cyclic Potentiodynamic Polarization (CPP) technique. This is a fast technique that gives rather accurate and reproducible values of re-passivation potential (ER1) in most cases. In the fringes of susceptibility, when the environment is not highly aggressive, the values of re-passivation potential using the CPP technique may not be highly reproducible, especially because the technique is fast. To circumvent this, the re-passivation potential of Alloy 22 was measured using a slower method that combines Potentiodynamic-Galvano-static-Potentiostatic steps (called here the Tsujikawa-Hisamatsu Electrochemical or THE method). The THE method applies the charge to the specimen in a more controlled way, which may give more reproducible re-passivation potential values, especially when the environment is not aggressive. The values of re-passivation potential of Alloy 22 in sodium chloride plus potassium nitrate solutions were measured using the THE and CPP methods. Results show that both methods yield similar values of re-passivation potential, especially under aggressive conditions. (authors)

  5. Ab initio pair potentials for FCC metals: An application of the method of Moebius transform

    International Nuclear Information System (INIS)

    Mookerjee, A.; Chen Nanxian; Kumar, V.; Satter, M.A.

    1991-10-01

    We use the method of Moebius transform introduced by one of us (Chen, Phys. Rev. Lett. 64, 1193 (1990)) to obtain pair potentials for fcc metals from first principles total energy calculations. The derivation is exact for radial potentials and it converges much faster than the earlier reported method of Carlsson-Gelatt-Ehrenreich. We have tested this formulation for Cu using the tight binding representation of the linear muffin tin orbital method. Our results agree with those obtained by Carlsson et al. and qualitatively with the other Morse-type pair potentials derived from effective medium theories. (author). 18 refs, 3 figs, 3 tabs

  6. A New Self-Constrained Inversion Method of Potential Fields Based on Probability Tomography

    Science.gov (United States)

    Sun, S.; Chen, C.; WANG, H.; Wang, Q.

    2014-12-01

    The self-constrained inversion method of potential fields uses a priori information self-extracted from potential field data. Differing from external a priori information, the self-extracted information are generally parameters derived exclusively from the analysis of the gravity and magnetic data (Paoletti et al., 2013). Here we develop a new self-constrained inversion method based on probability tomography. Probability tomography doesn't need any priori information, as well as large inversion matrix operations. Moreover, its result can describe the sources, especially the distribution of which is complex and irregular, entirely and clearly. Therefore, we attempt to use the a priori information extracted from the probability tomography results to constrain the inversion for physical properties. The magnetic anomaly data was taken as an example in this work. The probability tomography result of magnetic total field anomaly(ΔΤ) shows a smoother distribution than the anomalous source and cannot display the source edges exactly. However, the gradients of ΔΤ are with higher resolution than ΔΤ in their own direction, and this characteristic is also presented in their probability tomography results. So we use some rules to combine the probability tomography results of ∂ΔΤ⁄∂x, ∂ΔΤ⁄∂y and ∂ΔΤ⁄∂z into a new result which is used for extracting a priori information, and then incorporate the information into the model objective function as spatial weighting functions to invert the final magnetic susceptibility. Some magnetic synthetic examples incorporated with and without a priori information extracted from the probability tomography results were made to do comparison, results of which show that the former are more concentrated and with higher resolution of the source body edges. This method is finally applied in an iron mine in China with field measured ΔΤ data and performs well. ReferencesPaoletti, V., Ialongo, S., Florio, G., Fedi, M

  7. Relativistic extension of the Kay-Moses method for constructing transparent potentials in quantum mechanics

    International Nuclear Information System (INIS)

    Toyama, F.M.; Nogami, Y.; Zhao, Z.

    1993-01-01

    For the Dirac equation in one space dimension with a potential of the Lorentz scalar type, we present a complete solution for the problem of constructing a transparent potential. This is a relativistic extension of the Kay-Moses method which was developed for the nonrelativistic Schroedinger equation. There is an infinite family of transparent potentials. The potentials are all related to solutions of a class of coupled, nonlinear Dirac equations. In addition, it is argued that an admixture of a Lorentz vector component in the potential impairs perfect transparency

  8. Application of Exp-function method to potential Kadomtsev-Petviashvili equation

    International Nuclear Information System (INIS)

    Xian Daquan; Dai Zhengde

    2009-01-01

    Exact periodic kink-wave solution, periodic soliton and doubly periodic solutions for the potential Kadomtsev-Petviashvii (PKP) equation are obtained using Exp-function method with the help of Maple computation.

  9. V-amylose structural characteristics, methods of preparation, significance, and potential applications

    CSIR Research Space (South Africa)

    Obiro, WC

    2012-02-01

    Full Text Available , and postprandial hyperglycaemia in diabetics. Various aspects of V-amylose structure, methods of preparation, factors that affect its formation, and the significance and potential applications of the V-amylose complexes are reviewed....

  10. Double folding model of nucleus-nucleus potential: formulae, iteration method and computer code

    International Nuclear Information System (INIS)

    Luk'yanov, K.V.

    2008-01-01

    Method of construction of the nucleus-nucleus double folding potential is described. Iteration procedure for the corresponding integral equation is presented. Computer code and numerical results are presented

  11. Projection potentials and angular momentum convergence of total energies in the full-potential Korringa–Kohn–Rostoker method

    International Nuclear Information System (INIS)

    Zeller, Rudolf

    2013-01-01

    Although the full-potential Korringa–Kohn–Rostoker Green function method yields accurate results for many physical properties, the convergence of calculated total energies with respect to the angular momentum cutoff is usually considered to be less satisfactory. This is surprising because accurate single-particle energies are expected if they are calculated by Lloyd’s formula and because accurate densities and hence accurate double-counting energies should result from the total energy variational principle. It is shown how the concept of projection potentials can be used as a tool to analyse the convergence behaviour. The key factor blocking fast convergence is identified and it is illustrated how total energies can be improved with only a modest increase of computing time. (paper)

  12. On one pion exchange potential with quark exchange in the resonating group method

    International Nuclear Information System (INIS)

    Braeuer, K.; Faessler, A.; Fernandez, F.; Shimizu, K.

    1985-01-01

    The effect of quark exchange between different nucleons on the one pion exchange potential is studied in the framework of the resonating group method. The calculated phase shifts including the one pion exchange potential with quark exchange in addition to the one gluon plus sigma meson exchange are shown to be consistent with experiments. Especially the p-wave phase shifts are improved by taking into account the quark exchange on the one pion exchange potential. (orig.)

  13. Methods for increasing the biogas potential from the recalcitrant organic matter contained in manure

    DEFF Research Database (Denmark)

    Ahring, Birgitte Kiær; Angelidaki, Irini

    1998-01-01

    The biogas potential of manure could be significantly increased by treatment of the recalcitrant organic matter (biofibers) contained in the manure. Several treatment methods were tested. Mechanical maceration resulted in an average increase of the biogas potential of approx. 17% as shown...

  14. Application of quasiexactly solvable potential method to the N-body ...

    Indian Academy of Sciences (India)

    The quasiexactly solvable potential method is used to determine the energies and the corresponding exact eigenfunctions for a system of N particles with equal mass interacting via an anharmonic potential. For systems with five and seven particles, we compute the ground state and the first excited state only, and compare ...

  15. Novel Method for Sizing Metallic Bottom Crack Depth Using Multi-frequency Alternating Current Potential Drop Technique

    Science.gov (United States)

    Li, Yuting; Gan, Fangji; Wan, Zhengjun; Liao, Junbi; Li, Wenqiang

    2015-10-01

    Potential drop techniques are of two types: the direct current potential drop (DCPD) technique and alternating current potential drop (ACPD) technique, and both of them are used in nondestructive testing. ACPD, as a kind of valid method in sizing metal cracks, has been applied to evaluate metal structures. However, our review of most available approaches revealed that some improvements can be done in measuring depth of metal bottom crack by means of ACPD, such as accuracy and sensitivity of shallow crack. This paper studied a novel method which utilized the slope of voltage ratio-frequency curve to solve bottom crack depth by using a simple mathematic equation based on finite element analysis. It is found that voltage ratio varies linearly with frequency in the range of 5-15 Hz; this range is slightly higher than the equivalent frequency and lower than semi-permeable frequency. Simulation and experiment show that the novel method can measure the bottom crack depth accurately.

  16. The electrical self-potential method is a non-intrusive snow-hydrological sensor

    Science.gov (United States)

    Thompson, S. S.; Kulessa, B.; Essery, R. L. H.; Lüthi, M. P.

    2015-08-01

    Our ability to measure, quantify and assimilate hydrological properties and processes of snow in operational models is disproportionally poor compared to the significance of seasonal snowmelt as a global water resource and major risk factor in flood and avalanche forecasting. Encouraged by recent theoretical, modelling and laboratory work, we show here that the diurnal evolution of aerially-distributed self-potential magnitudes closely track those of bulk meltwater fluxes in melting in-situ snowpacks at Rhone and Jungfraujoch glaciers, Switzerland. Numerical modelling infers temporally-evolving liquid water contents in the snowpacks on successive days in close agreement with snow-pit measurements. Muting previous concerns, the governing physical and chemical properties of snow and meltwater became temporally invariant for modelling purposes. Because measurement procedure is straightforward and readily automated for continuous monitoring over significant spatial scales, we conclude that the self-potential geophysical method is a highly-promising non-intrusive snow-hydrological sensor for measurement practice, modelling and operational snow forecasting.

  17. Some free boundary problems in potential flow regime usinga based level set method

    Energy Technology Data Exchange (ETDEWEB)

    Garzon, M.; Bobillo-Ares, N.; Sethian, J.A.

    2008-12-09

    Recent advances in the field of fluid mechanics with moving fronts are linked to the use of Level Set Methods, a versatile mathematical technique to follow free boundaries which undergo topological changes. A challenging class of problems in this context are those related to the solution of a partial differential equation posed on a moving domain, in which the boundary condition for the PDE solver has to be obtained from a partial differential equation defined on the front. This is the case of potential flow models with moving boundaries. Moreover the fluid front will possibly be carrying some material substance which will diffuse in the front and be advected by the front velocity, as for example the use of surfactants to lower surface tension. We present a Level Set based methodology to embed this partial differential equations defined on the front in a complete Eulerian framework, fully avoiding the tracking of fluid particles and its known limitations. To show the advantages of this approach in the field of Fluid Mechanics we present in this work one particular application: the numerical approximation of a potential flow model to simulate the evolution and breaking of a solitary wave propagating over a slopping bottom and compare the level set based algorithm with previous front tracking models.

  18. Imaginary Time Step Method to Solve the Dirac Equation with Nonlocal Potential

    International Nuclear Information System (INIS)

    Zhang Ying; Liang Haozhao; Meng Jie

    2009-01-01

    The imaginary time step (ITS) method is applied to solve the Dirac equation with nonlocal potentials in coordinate space. Taking the nucleus 12 C as an example, even with nonlocal potentials, the direct ITS evolution for the Dirac equation still meets the disaster of the Dirac sea. However, following the recipe in our former investigation, the disaster can be avoided by the ITS evolution for the corresponding Schroedinger-like equation without localization, which gives the convergent results exactly the same with those obtained iteratively by the shooting method with localized effective potentials.

  19. An efficient method to find potentially universal population genetic markers, applied to metazoans

    Directory of Open Access Journals (Sweden)

    Chenuil Anne

    2010-09-01

    Full Text Available Abstract Background Despite the impressive growth of sequence databases, the limited availability of nuclear markers that are sufficiently polymorphic for population genetics and phylogeography and applicable across various phyla restricts many potential studies, particularly in non-model organisms. Numerous introns have invariant positions among kingdoms, providing a potential source for such markers. Unfortunately, most of the few known EPIC (Exon Primed Intron Crossing loci are restricted to vertebrates or belong to multigenic families. Results In order to develop markers with broad applicability, we designed a bioinformatic approach aimed at avoiding multigenic families while identifying intron positions conserved across metazoan phyla. We developed a program facilitating the identification of EPIC loci which allowed slight variation in intron position. From the Homolens databases we selected 29 gene families which contained 52 promising introns for which we designed 93 primer pairs. PCR tests were performed on several ascidians, echinoderms, bivalves and cnidarians. On average, 24 different introns per genus were amplified in bilaterians. Remarkably, five of the introns successfully amplified in all of the metazoan genera tested (a dozen genera, including cnidarians. The influence of several factors on amplification success was investigated. Success rate was not related to the phylogenetic relatedness of a taxon to the groups that most influenced primer design, showing that these EPIC markers are extremely conserved in animals. Conclusions Our new method now makes it possible to (i rapidly isolate a set of EPIC markers for any phylum, even outside the animal kingdom, and thus, (ii compare genetic diversity at potentially homologous polymorphic loci between divergent taxa.

  20. A new method to detect event-related potentials based on Pearson's correlation.

    Science.gov (United States)

    Giroldini, William; Pederzoli, Luciano; Bilucaglia, Marco; Melloni, Simone; Tressoldi, Patrizio

    2016-12-01

    Event-related potentials (ERPs) are widely used in brain-computer interface applications and in neuroscience.  Normal EEG activity is rich in background noise, and therefore, in order to detect ERPs, it is usually necessary to take the average from multiple trials to reduce the effects of this noise.  The noise produced by EEG activity itself is not correlated with the ERP waveform and so, by calculating the average, the noise is decreased by a factor inversely proportional to the square root of N , where N is the number of averaged epochs. This is the easiest strategy currently used to detect ERPs, which is based on calculating the average of all ERP's waveform, these waveforms being time- and phase-locked.  In this paper, a new method called GW6 is proposed, which calculates the ERP using a mathematical method based only on Pearson's correlation. The result is a graph with the same time resolution as the classical ERP and which shows only positive peaks representing the increase-in consonance with the stimuli-in EEG signal correlation over all channels.  This new method is also useful for selectively identifying and highlighting some hidden components of the ERP response that are not phase-locked, and that are usually hidden in the standard and simple method based on the averaging of all the epochs.  These hidden components seem to be caused by variations (between each successive stimulus) of the ERP's inherent phase latency period (jitter), although the same stimulus across all EEG channels produces a reasonably constant phase. For this reason, this new method could be very helpful to investigate these hidden components of the ERP response and to develop applications for scientific and medical purposes. Moreover, this new method is more resistant to EEG artifacts than the standard calculations of the average and could be very useful in research and neurology.  The method we are proposing can be directly used in the form of a process written in the well

  1. Application of quasiexactly solvable potential method to the N-body ...

    Indian Academy of Sciences (India)

    physics pp. 985–996. Application of quasiexactly solvable potential method to the N-body ... Application of QES method to N-particle quantum model interacting via an ... Now, if we choose the centre of mass R as the origin of the coordinates,.

  2. Crack monitoring method based on Cu coating sensor and electrical potential technique for metal structure

    Directory of Open Access Journals (Sweden)

    Hou Bo

    2015-06-01

    Full Text Available Advanced crack monitoring technique is the cornerstone of aircraft structural health monitoring. To achieve real-time crack monitoring of aircraft metal structures in the course of service, a new crack monitoring method is proposed based on Cu coating sensor and electrical potential difference principle. Firstly, insulation treatment process was used to prepare a dielectric layer on structural substrate, such as an anodizing layer on 2A12-T4 aluminum alloy substrate, and then a Cu coating crack monitoring sensor was deposited on the structure fatigue critical parts by pulsed bias arc ion plating technology. Secondly, the damage consistency of the Cu coating sensor and 2A12-T4 aluminum alloy substrate was investigated by static tensile experiment and fatigue test. The results show that strain values of the coating sensor and the 2A12-T4 aluminum alloy substrate measured by strain gauges are highly coincident in static tensile experiment and the sensor has excellent fatigue damage consistency with the substrate. Thirdly, the fatigue performance discrepancy between samples with the coating sensor and original samples was investigated. The result shows that there is no obvious negative influence on the fatigue performance of the 2A12-T4 aluminum alloy after preparing the Cu coating sensor on its surface. Finally, crack monitoring experiment was carried out with the Cu coating sensor. The experimental results indicate that the sensor is sensitive to crack, and crack origination and propagation can be monitored effectively through analyzing the change of electrical potential values of the coating sensor.

  3. A new method for solving the two-center problem with relativistic potentials

    International Nuclear Information System (INIS)

    Gareev, F.A.; Gizzatkulov, M.Ch.

    1977-01-01

    A method has been proposed for the solution of the two-center problem with realistic potentials. It consists of two steps: first, a separable approximation to the single particle potentials is made and then the two-center problem with these separable potentials is solved exactly. The only approximations are introduced at the first stage in a well controllable way. As an example, we have calculated the single-particle energies and wave functions in the field of two 16 O like the Woods-Saxon potentials as functions of their distance R

  4. Modified embedded-atom method interatomic potential for the Fe-Al system

    International Nuclear Information System (INIS)

    Lee, Eunkoo; Lee, Byeong-Joo

    2010-01-01

    An interatomic potential for the Fe-Al binary system has been developed based on the modified embedded-atom method (MEAM) potential formalism. The potential can describe various fundamental physical properties of Fe-Al binary alloys-structural, elastic and thermodynamic properties, defect formation behavior and interactions between defects-in reasonable agreement with experimental data or higher-level calculations. The applicability of the potential to atomistic investigations of various defect formation behaviors and their effects on the mechanical properties of high aluminum steels as well as Fe-Al binary alloys is demonstrated.

  5. METHODS OF DETERMINATION THE INTERIOR POTENTIAL OF ENTERPRISE IN MAKING STRATEGICAL ASSORTMENT DECISIONS

    Directory of Open Access Journals (Sweden)

    Svitlana Malyuk

    2015-11-01

    Full Text Available The analysis of the internal environment of the enterprise is aimed at assessing the strategic potential of the enterprise as a whole and its individual functional subsystems. The efficient activity of enterprise cannot be realized without a systematic definition and using the existing capabilities since, as a rule, the potential of the organization is higher than its actual implementation. It is not possible to put forward long-term goals, to form the most optimal strategy to achieve them without the characteristics of accumulated enterprises potential. From this point, the purpose of the paper is to study and establish the criteria that characterize the inner potential of the company during the implementation of assortment strategies. The method of evaluating of these indicators, as well as the selection of the assortment strategy according to the results has been suggested. Methods. The research of the internal potential of PJSC “Mykolaiv bakery № 1” is based on the expert questionnaire, which made it possible not only to identify a number of criteria for internal enterprises environment, which made it possible not only to identify a number of criteria for internal environment, as well as by experts to determine the parameter and boundary values of coefficients influencing the choice of the assortment strategy. The results of questionnaire showed that the main criteria of the characteristics of the internal potential of the company are: primary phases of the life cycle of the goods (were determined on the basis of the matrix "Market growth – Market Share"; prospects of producing the assortment groups of goods (calculated using the integral coefficient of goods assortment; changes in sales amount (described by trigonometric dependencies; degree of the goods assortment realization (evaluated using the coefficient of realization; assortments balance according to the Pareto rule (based on the Pareto rule, as well as expert survey; the

  6. Effective nucleus-nucleus potentials derived from the generator coordinate method

    Energy Technology Data Exchange (ETDEWEB)

    Friedrich, H; Canto, L F [Oxford Univ. (UK). Dept. of Theoretical Physics

    1977-11-07

    The equivalence of the generator coordinate method (GCM) and the resonating group method (RGM) and the formal equivalence of the RGM and the orthogonality condition model (OCM) lead to a relation connecting the effective nucleus-nucleus potentials of the OCM with matrix elements of the GCM. This relation may be used to derive effective nucleus-nucleus potentials directly from GCM matrix elements without explicit reference to the potentials of the RGM. In a first application local and l-independent effective potentials are derived from diagonal GCM matrix elements which represent the energy surfaces of a two-centre shell model. Using these potentials the OCM can reproduce the results of a full RGM calculation very well for the elastic scattering of two ..cap alpha..-particles and fairly well for elastic /sup 16/O-/sup 16/O scattering.

  7. Estimation of potential evapotranspiration of a coastal savannah environment; comparison of methods

    International Nuclear Information System (INIS)

    Asare, D.K.; Ayeh, E.O.; Amenorpe, G.; Banini, G.K.

    2011-01-01

    Six potential evapotranspiration models namely, Penman-Monteith, Hargreaves-Samani , Priestley-Taylor, IRMAK1, IRMAK2 and TURC, were used to estimate daily PET values at Atomic-Kwabenya in the coastal savannah environment of Ghana for the year 2005. The study compared PET values generated by six models and identified which ones compared favourably with the Penman-Monteith model which is the recommended standard method for estimating PET. Cross comparison analysis showed that only the daily estimates of PET of Hargreaves-Samani model correlated reasonably (r = 0.82) with estimates by the Penman-Monteith model. Additionally, PET values by the Priestley-Taylor and TURC models were highly correlated (r = 0.99) as well as those generated by IRMAK2 and TURC models (r = 0.96). Statistical analysis, based on pair comparison of means, showed that daily PET estimates of the Penman-Monteith model were not different from the Priestley-Taylor model for the Kwabenya-Atomic area located in the coastal savannah environment of Ghana. The Priestley-Taylor model can be used, in place of the Penman-Monteith model, to estimate daily PET for the Atomic-Kwabenya area of the coastal savannah environment of Ghana. The Hargreaves-Samani model can also be used to estimate PET for the study area because its PET estimates correlated reasonably with those of the Penman-Monteith model (r = 0.82) and requires only air temperature measurements as inputs. (au)

  8. Dynamic fracture testing of ferritic steels using direct current potential drop method

    International Nuclear Information System (INIS)

    Oh, Y. J.; Kim, J. H.; Hwang, I. S.; Park, Y. W.

    2000-01-01

    To apply leak-before-break (LBB) concept to nuclear pipes, the dynamic strain aging of low carbon steel materials has to be considered. For this goal, the J-R tests are needed over a range of temperatures and loading rates, including rapid dynamic loading conditions. In dynamic J-R tests, the unloading compliance method can not be applied and usually the direct current potential drop (DCPD) method has been used. But, even the DCPD method was known to have the problem in defining the crack initiation point due to a potential peak arising in early part of loading of ferromagnetic materials. In this study, potential peaks characteristics were investigated for SA106Gr.C piping steels, and the definition of crack initiation point was made by back tracking from final physical crack length, and it was proposed that this technique could be applied to DCPD method in dynamic loading J-R test

  9. Screening of Potential Remediation Methods for the 200-ZP-1 Operable Unit at the Hanford Site

    Energy Technology Data Exchange (ETDEWEB)

    Truex, Michael J.; Nimmons, Michael J.; Johnson, Christian D.; Dresel, P EVAN.; Murray, Christopher J.

    2006-08-07

    A screening-level evaluation of potential remediation methods for application to the contaminants of concern (COC) in the 200-ZP-1 Operable Unit at the Hanford Site was conducted based on the methods outlined in the Guidance for Conducting Remedial Investigations and Feasibility Studies under CERCLA Interim Final. The scope of this screening was to identify the most promising remediation methods for use in the more detailed analysis of remediation alternatives that will be conducted as part of the full feasibility study. The screening evaluation was conducted for the primary COC (potential major risk drivers). COC with similar properties were grouped for the screening evaluation. The screening evaluation was conducted in two primary steps. The initial screening step evaluated potential remediation methods based on whether they can be effectively applied within the environmental setting of the 200-ZP-1 Operable Unit for the specified contaminants. In the second step, potential remediation methods were screened using scoping calculations to estimate the scale of infrastructure, overall quantities of reagents, and conceptual approach for applying the method for each defined grouping of COC. Based on these estimates, each method was screened with respect to effectiveness, implementability, and relative cost categories of the CERCLA feasibility study screening process defined in EPA guidance.

  10. Determining the potential independent critical pitting temperature (CPT) by a potentiostatic method using the Avesta Cell

    International Nuclear Information System (INIS)

    Arnvig, P.E.; Bisgard, A.D.

    1996-01-01

    The development of a potentiostatic method for determining the potential independent Critical Pitting Temperature (CPT) using the Avesta Cell is presented. The new potentiostatic method has been used to determine the CPT for austenitic stainless steels. The precision of the potentiostatic method of approximately ±2 C is close to that of the traditional potentiodynamic method. The time required to determine a CPT is much shorter than when using the potentiodynamic method. A CPT is obtained within 1.5 to 3 hours for each specimen. The influence of various experimental parameters such as electrochemical potential, evaluation criteria for the CPT, test area, stabilization time prior to polarization and inert gas purging is described. The lack of sensitivity towards many of these parameters as well as the high reproducibility obtained is associated with fundamentals of the pitting process. It is argued that the potential independent CPT characterizes the stable propagating pitting event as opposed to the potential dependent CPT or pitting potentials, which to a larger extent are affected by the nucleation part of the pitting process

  11. Streaming Potential Modeling to Understand the Identification of Hydraulically Active Fractures and Fracture-Matrix Fluid Interactions Using the Self-Potential Method

    Science.gov (United States)

    Jougnot, D.; Roubinet, D.; Linde, N.; Irving, J.

    2016-12-01

    Quantifying fluid flow in fractured media is a critical challenge in a wide variety of research fields and applications. To this end, geophysics offers a variety of tools that can provide important information on subsurface physical properties in a noninvasive manner. Most geophysical techniques infer fluid flow by data or model differencing in time or space (i.e., they are not directly sensitive to flow occurring at the time of the measurements). An exception is the self-potential (SP) method. When water flows in the subsurface, an excess of charge in the pore water that counterbalances electric charges at the mineral-pore water interface gives rise to a streaming current and an associated streaming potential. The latter can be measured with the SP technique, meaning that the method is directly sensitive to fluid flow. Whereas numerous field experiments suggest that the SP method may allow for the detection of hydraulically active fractures, suitable tools for numerically modeling streaming potentials in fractured media do not exist. Here, we present a highly efficient two-dimensional discrete-dual-porosity approach for solving the fluid-flow and associated self-potential problems in fractured domains. Our approach is specifically designed for complex fracture networks that cannot be investigated using standard numerical methods due to computational limitations. We then simulate SP signals associated with pumping conditions for a number of examples to show that (i) accounting for matrix fluid flow is essential for accurate SP modeling and (ii) the sensitivity of SP to hydraulically active fractures is intimately linked with fracture-matrix fluid interactions. This implies that fractures associated with strong SP amplitudes are likely to be hydraulically conductive, attracting fluid flow from the surrounding matrix.

  12. Groundwater exploration by self-potential method; Shizen den`iho ni yoru chikasui tansa

    Energy Technology Data Exchange (ETDEWEB)

    Onaru, I; Irie, S; Mizunaga, H; Ushijima, K [Kyushu University, Fukuoka (Japan). Faculty of Engineering

    1997-05-27

    This paper describes results measured from the field experiments and data analysis of the groundwater exploration by self-potential method. The field survey was conducted in the vicinity of spring water source in the suburbs of Fukuoka City. For the field experiments, potential differences from the standard potential electrode set at the distance about 200 m were measured at multi-points, simultaneously. For the laboratory experiments, assuming that the groundwater flows in a permeable layer, streaming potential change was observed against the changes of flow rate and electrical conductivity. Thus, the generation of streaming potential was investigated. For the experiment using specimens obtained at the spring water source, the potential changed to negative and was stabilized in around -80 mV after 15 minutes. Numerical simulation was conducted by means of the three-dimensional finite difference method using parameters obtained from the laboratory experiments. From these results, the groundwater flow image could be obtained. It was also confirmed that the self-potential observed in the spring water source area was caused by the streaming potential. 11 refs., 9 figs.

  13. Use of a novel cell adhesion method and digital measurement to show stimulus-dependent variation in somatic and oral ciliary beat frequency in Paramecium.

    Science.gov (United States)

    Bell, Wade E; Hallworth, Richard; Wyatt, Todd A; Sisson, Joseph H

    2015-01-01

    When Paramecium encounters positive stimuli, the membrane hyperpolarizes and ciliary beat frequency increases. We adapted an established immobilization protocol using a biological adhesive and a novel digital analysis system to quantify beat frequency in immobilized Paramecium. Cells showed low mortality and demonstrated beat frequencies consistent with previous studies. Chemoattractant molecules, reduction in external potassium, and posterior stimulation all increased somatic beat frequency. In all cases, the oral groove cilia maintained a higher beat frequency than mid-body cilia, but only oral cilia from cells stimulated with chemoattactants showed an increase from basal levels. © 2014 The Author(s) Journal of Eukaryotic Microbiology © 2014 International Society of Protistologists.

  14. Assessment of geothermal energy potential by geophysical methods: Nevşehir Region, Central Anatolia

    Science.gov (United States)

    Kıyak, Alper; Karavul, Can; Gülen, Levent; Pekşen, Ertan; Kılıç, A. Rıza

    2015-03-01

    In this study, geothermal potential of the Nevşehir region (Central Anatolia) was assessed by using vertical electrical sounding (VES), self-potential (SP), magnetotelluric (MT), gravity and gravity 3D Euler deconvolution structure analysis methods. Extensive volcanic activity occurred in this region from Upper Miocene to Holocene time. Due to the young volcanic activity Nevşehir region can be viewed as a potential geothermal area. We collected data from 54 VES points along 5 profiles, from 28 MT measurement points along 2 profiles (at frequency range between 320 and 0.0001 Hz), and from 4 SP profiles (total 19 km long). The obtained results based on different geophysical methods are consistent with each other. Joint interpretation of all geological and geophysical data suggests that this region has geothermal potential and an exploration well validated this assessment beyond doubt.

  15. Solution of the schrodinger equation in one dimension by simple method for a simple step potential

    International Nuclear Information System (INIS)

    Ertik, H.

    2005-01-01

    The coefficients of the transmission and reflection for the simple-step barrier potential were calculated by a simple method. Their values were entirely different from those often encountered in the literature. Especially in the case that the total energy is equal to the barrier potential, the value of 0,20 for the reflection coefficient was obtained whereas this is zero in the literature. This may be considered as an interesting point

  16. Sensitivity of radiation methods of diagnosis of electric potentials in dielectric materials

    International Nuclear Information System (INIS)

    Sapozhkov, Yu.I.; Smekalin, L.F.; Yagushkin, N.I.

    1985-01-01

    On the base of the albedo method the characteristics of radiation methods of diagnosis of electric potentials inside dielectrics, such as sensitivity and resolution are considered. Investigations are carried out for electron energies of tens keV. It is shown that with energy growth the sensitivity to electric field in the dielectrics volume drops. The target atomic number growth reduces the sensitivity approximately 1/lnz. The albedo method resolution in the investigated energy range is constant. The results obtained testify to the usability radiation methods of the diagnosis for control of electric fields of dielectric structural materials in the course of their operation

  17. Charge-transfer modified embedded atom method dynamic charge potential for Li-Co-O system.

    Science.gov (United States)

    Kong, Fantai; Longo, Roberto C; Liang, Chaoping; Nie, Yifan; Zheng, Yongping; Zhang, Chenxi; Cho, Kyeongjae

    2017-11-29

    To overcome the limitation of conventional fixed charge potential methods for the study of Li-ion battery cathode materials, a dynamic charge potential method, charge-transfer modified embedded atom method (CT-MEAM), has been developed and applied to the Li-Co-O ternary system. The accuracy of the potential has been tested and validated by reproducing a variety of structural and electrochemical properties of LiCoO 2 . A detailed analysis on the local charge distribution confirmed the capability of this potential for dynamic charge modeling. The transferability of the potential is also demonstrated by its reliability in describing Li-rich Li 2 CoO 2 and Li-deficient LiCo 2 O 4 compounds, including their phase stability, equilibrium volume, charge states and cathode voltages. These results demonstrate that the CT-MEAM dynamic charge potential could help to overcome the challenge of modeling complex ternary transition metal oxides. This work can promote molecular dynamics studies of Li ion cathode materials and other important transition metal oxides systems that involve complex electrochemical and catalytic reactions.

  18. Generalized Heisenberg algebra and algebraic method: The example of an infinite square-well potential

    International Nuclear Information System (INIS)

    Curado, E.M.F.; Hassouni, Y.; Rego-Monteiro, M.A.; Rodrigues, Ligia M.C.S.

    2008-01-01

    We discuss the role of generalized Heisenberg algebras (GHA) in obtaining an algebraic method to describe physical systems. The method consists in finding the GHA associated to a physical system and the relations between its generators and the physical observables. We choose as an example the infinite square-well potential for which we discuss the representations of the corresponding GHA. We suggest a way of constructing a physical realization of the generators of some GHA and apply it to the square-well potential. An expression for the position operator x in terms of the generators of the algebra is given and we compute its matrix elements

  19. An induced current method for measuring zeta potential of electrolyte solution-air interface.

    Science.gov (United States)

    Song, Yongxin; Zhao, Kai; Wang, Junsheng; Wu, Xudong; Pan, Xinxiang; Sun, Yeqing; Li, Dongqing

    2014-02-15

    This paper reports a novel and very simple method for measuring the zeta potential of electrolyte solution-air interface. When a measuring electrode contacts the electrolyte solution-air interface, an electrical current will be generated due to the potential difference between the electrode-air surface and the electrolyte solution-air interface. The amplitude of the measured electric signal is linearly proportional to this potential difference; and depends only on the zeta potential at the electrolyte solution-air interface, regardless of the types and concentrations of the electrolyte. A correlation between the zeta potential and the measured voltage signal is obtained based on the experimental data. Using this equation, the zeta potential of any electrolyte solution-air interface can be evaluated quickly and easily by inserting an electrode through the electrolyte solution-air interface and measuring the electrical signal amplitude. This method was verified by comparing the obtained results of NaCl, MgCl2 and CaCl2 solutions of different pH values and concentrations with the zeta potential data reported in the published journal papers. Copyright © 2013 Elsevier Inc. All rights reserved.

  20. Spectral neighbor analysis method for automated generation of quantum-accurate interatomic potentials

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, Aidan P. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States). Multiscale Science Dept.; Swiler, Laura P. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States). Optimization and Uncertainty Quantification Dept.; Trott, Christian R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Scalable Algorithms Dept.; Foiles, Stephen M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Computational Materials and Data Science Dept.; Tucker, Garritt J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Computational Materials and Data Science Dept.; Drexel Univ., Philadelphia, PA (United States). Dept. of Materials Science and Engineering

    2015-03-15

    Here, we present a new interatomic potential for solids and liquids called Spectral Neighbor Analysis Potential (SNAP). The SNAP potential has a very general form and uses machine-learning techniques to reproduce the energies, forces, and stress tensors of a large set of small configurations of atoms, which are obtained using high-accuracy quantum electronic structure (QM) calculations. The local environment of each atom is characterized by a set of bispectrum components of the local neighbor density projected onto a basis of hyperspherical harmonics in four dimensions. The bispectrum components are the same bond-orientational order parameters employed by the GAP potential [1]. The SNAP potential, unlike GAP, assumes a linear relationship between atom energy and bispectrum components. The linear SNAP coefficients are determined using weighted least-squares linear regression against the full QM training set. This allows the SNAP potential to be fit in a robust, automated manner to large QM data sets using many bispectrum components. The calculation of the bispectrum components and the SNAP potential are implemented in the LAMMPS parallel molecular dynamics code. We demonstrate that a previously unnoticed symmetry property can be exploited to reduce the computational cost of the force calculations by more than one order of magnitude. We present results for a SNAP potential for tantalum, showing that it accurately reproduces a range of commonly calculated properties of both the crystalline solid and the liquid phases. In addition, unlike simpler existing potentials, SNAP correctly predicts the energy barrier for screw dislocation migration in BCC tantalum.

  1. Spectral neighbor analysis method for automated generation of quantum-accurate interatomic potentials

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, A.P., E-mail: athomps@sandia.gov [Multiscale Science Department, Sandia National Laboratories, PO Box 5800, MS 1322, Albuquerque, NM 87185 (United States); Swiler, L.P., E-mail: lpswile@sandia.gov [Optimization and Uncertainty Quantification Department, Sandia National Laboratories, PO Box 5800, MS 1318, Albuquerque, NM 87185 (United States); Trott, C.R., E-mail: crtrott@sandia.gov [Scalable Algorithms Department, Sandia National Laboratories, PO Box 5800, MS 1322, Albuquerque, NM 87185 (United States); Foiles, S.M., E-mail: foiles@sandia.gov [Computational Materials and Data Science Department, Sandia National Laboratories, PO Box 5800, MS 1411, Albuquerque, NM 87185 (United States); Tucker, G.J., E-mail: gtucker@coe.drexel.edu [Computational Materials and Data Science Department, Sandia National Laboratories, PO Box 5800, MS 1411, Albuquerque, NM 87185 (United States); Department of Materials Science and Engineering, Drexel University, Philadelphia, PA 19104 (United States)

    2015-03-15

    We present a new interatomic potential for solids and liquids called Spectral Neighbor Analysis Potential (SNAP). The SNAP potential has a very general form and uses machine-learning techniques to reproduce the energies, forces, and stress tensors of a large set of small configurations of atoms, which are obtained using high-accuracy quantum electronic structure (QM) calculations. The local environment of each atom is characterized by a set of bispectrum components of the local neighbor density projected onto a basis of hyperspherical harmonics in four dimensions. The bispectrum components are the same bond-orientational order parameters employed by the GAP potential [1]. The SNAP potential, unlike GAP, assumes a linear relationship between atom energy and bispectrum components. The linear SNAP coefficients are determined using weighted least-squares linear regression against the full QM training set. This allows the SNAP potential to be fit in a robust, automated manner to large QM data sets using many bispectrum components. The calculation of the bispectrum components and the SNAP potential are implemented in the LAMMPS parallel molecular dynamics code. We demonstrate that a previously unnoticed symmetry property can be exploited to reduce the computational cost of the force calculations by more than one order of magnitude. We present results for a SNAP potential for tantalum, showing that it accurately reproduces a range of commonly calculated properties of both the crystalline solid and the liquid phases. In addition, unlike simpler existing potentials, SNAP correctly predicts the energy barrier for screw dislocation migration in BCC tantalum.

  2. Spectral neighbor analysis method for automated generation of quantum-accurate interatomic potentials

    International Nuclear Information System (INIS)

    Thompson, A.P.; Swiler, L.P.; Trott, C.R.; Foiles, S.M.; Tucker, G.J.

    2015-01-01

    We present a new interatomic potential for solids and liquids called Spectral Neighbor Analysis Potential (SNAP). The SNAP potential has a very general form and uses machine-learning techniques to reproduce the energies, forces, and stress tensors of a large set of small configurations of atoms, which are obtained using high-accuracy quantum electronic structure (QM) calculations. The local environment of each atom is characterized by a set of bispectrum components of the local neighbor density projected onto a basis of hyperspherical harmonics in four dimensions. The bispectrum components are the same bond-orientational order parameters employed by the GAP potential [1]. The SNAP potential, unlike GAP, assumes a linear relationship between atom energy and bispectrum components. The linear SNAP coefficients are determined using weighted least-squares linear regression against the full QM training set. This allows the SNAP potential to be fit in a robust, automated manner to large QM data sets using many bispectrum components. The calculation of the bispectrum components and the SNAP potential are implemented in the LAMMPS parallel molecular dynamics code. We demonstrate that a previously unnoticed symmetry property can be exploited to reduce the computational cost of the force calculations by more than one order of magnitude. We present results for a SNAP potential for tantalum, showing that it accurately reproduces a range of commonly calculated properties of both the crystalline solid and the liquid phases. In addition, unlike simpler existing potentials, SNAP correctly predicts the energy barrier for screw dislocation migration in BCC tantalum

  3. The determination of the irritancy potential of surfactants using various methods of assessment.

    Science.gov (United States)

    Ciuchta, H P; Dodd, K T

    1978-01-01

    Several animal irritancy test methods whose criteria include sensory response, pain/discomfort or tissue damage were evaluated as to their ability to assess relative irritancy potential of the following surfactants: sodium lauryl polyether (12) sulfate (SLES), Miranol C2M (MC2M), Miranol MHT (MMHT), sodium coco methyl tauride (SCMT), triethanolamine lauryl sulfate (TEALS), ammonium lauryl sulfate (ALS) and sodium lauryl sulfate (SLS). Data from the mouse upper respiratory tract and mouse writhing tests indicated that SLES, MC2M and MMHT were the least irritating and SLS, ALS and TEALS were the most irritating. The blepharospasm test did not lend itself to this type of evaluation because sequential instillation of the surfactants produced eye anesthesia. Data from the Draize eye test indicated that SLES was the least irritating while MC2M was slightly more irritating. All other surfactants were equally irritating. The Draize skin test results showed that SLES again was the least irritating at all concentrations tested and that SLS and ALS along with TEALS and SCMT were the most irritating.

  4. Identification of aquifer potential in Karanganyar city by using vertical electrical sounding method

    Science.gov (United States)

    Marfuatik, L.; Koesuma, S.; Legowo, B.; Darsono

    2018-03-01

    The identification of aquifer was done by using Vertical Electrical Sounding (VES) method. This research aims to identify potential and depth of the aquifers. The locations of surveys are at ten points,namely TS1 (Alastuwo), TS2 (Wonorejo), TS3 (Kaling), TS4 (Kaling), TS5 (Buran), TS6 (Wonolopo), TS7 (Buran), TS8 (Ngijo), TS9 (Jati), and TS10 (Suruhkalang) where all located in Karanganyar regency. The survey path is about 500-600 meters length which can penetrate current to 100 – 200 meters in depth. The measurement was done by using OYO Mc OHM-EL Model 2119C. Geoelectrical data analysis was processed using Progress version 3.0 Software. The interpretation result shows that the locations of research area are included in Lawu-volcano rock formation which is breccias, lava, and tuff as the constituents. We found that unconfined aquifer in all of locations with different depth and confined aquifer just 7 locations start from 25.04 meters.

  5. The Prediction Methods for Potential Suspended Solids Clogging Types during Managed Aquifer Recharge

    Directory of Open Access Journals (Sweden)

    Xinqiang Du

    2014-04-01

    Full Text Available The implementation and development of managed aquifer recharge (MAR have been limited by the clogging attributed to physical, chemical, and biological reactions. In application field of MAR, physical clogging is usually the dominant type. Although numerous studies on the physical clogging mechanism during MAR are available, studies on the more detailed suspended clogging types and its prediction methods still remain few. In this study, a series of column experiments were inducted to show the process of suspended solids clogging process. The suspended solids clogging was divided into three types of surface clogging, inner clogging and mixed clogging based on the different clogging characteristics. Surface clogging indicates that the suspended solids are intercepted by the medium surface when suspended solids grain diameter is larger than pore diameter of infiltration medium. Inner clogging indicates that the suspended solids particles could transport through the infiltration medium. Mixed clogging refers to the comprehensive performance of surface clogging and inner clogging. Each suspended solids clogging type has the different clogging position, different changing laws of hydraulic conductivity and different deposition profile of suspended solids. Based on the experiment data, the ratio of effective medium pore diameter (Dp and median grain size of suspended solids (d50 was proposed as the judgment index for suspended solids clogging types. Surface clogging occurred while Dp/d50 was less than 5.5, inner clogging occurred while Dp/d50 was greater than 180, and mixed clogging occurred while Dp/d50 was between 5.5 and 180. In order to improve the judgment accuracy and applicability, Bayesian method, which considered more ratios of medium pore diameter (Dp and different level of grain diameter of suspended solids (di, were developed to predict the potential suspended solids types.

  6. An evaluation of diverse methods of obtaining effective Schroedinger interaction potentials for elastic scattering

    International Nuclear Information System (INIS)

    Amos, K.; Allen, L.J.; Steward, C.; Hodgson, P.E.; Sofianos, S.A.

    1995-01-01

    Direct solution of the Schroedinger equation and inversion methods of analysis of elastic scattering data are considered to evaluate the information that they can provide about the physical interaction between colliding nuclear particles. It was found that both optical model and inversion methods based upon inverse scattering theories are subject to ambiguities. Therefore, it is essential that elastic scattering data analyses are consistent with microscopic calculations of the potential. 25 refs

  7. An evaluation of diverse methods of obtaining effective Schroedinger interaction potentials for elastic scattering

    Energy Technology Data Exchange (ETDEWEB)

    Amos, K.; Allen, L.J.; Steward, C. [Melbourne Univ., Parkville, VIC (Australia). School of Physics; Hodgson, P.E. [Oxford Univ. (United Kingdom). Dept. of Physics; Sofianos, S.A. [University of South Africa (UNISA), Pretoria (South Africa). Dept. of Physics

    1995-10-01

    Direct solution of the Schroedinger equation and inversion methods of analysis of elastic scattering data are considered to evaluate the information that they can provide about the physical interaction between colliding nuclear particles. It was found that both optical model and inversion methods based upon inverse scattering theories are subject to ambiguities. Therefore, it is essential that elastic scattering data analyses are consistent with microscopic calculations of the potential. 25 refs.

  8. Novel Method To Identify Source-Associated Phylogenetic Clustering Shows that Listeria monocytogenes Includes Niche-Adapted Clonal Groups with Distinct Ecological Preferences

    DEFF Research Database (Denmark)

    Nightingale, K. K.; Lyles, K.; Ayodele, M.

    2006-01-01

    population are identified (TreeStats test). Analysis of sequence data for 120 L. monocytogenes isolates revealed evidence of clustering between isolates from the same source, based on the phylogenies inferred from actA and inlA (P = 0.02 and P = 0.07, respectively; SourceCluster test). Overall, the Tree...... are biologically valid. Overall, our data show that (i) the SourceCluster and TreeStats tests can identify biologically meaningful source-associated phylogenetic clusters and (ii) L. monocytogenes includes clonal groups that have adapted to infect specific host species or colonize nonhost environments......., including humans, animals, and food. If the null hypothesis that the genetic distances for isolates within and between source populations are identical can be rejected (SourceCluster test), then particular clades in the phylogenetic tree with significant overrepresentation of sequences from a given source...

  9. Efficient methods for including quantum effects in Monte Carlo calculations of large systems: extension of the displaced points path integral method and other effective potential methods to calculate properties and distributions.

    Science.gov (United States)

    Mielke, Steven L; Dinpajooh, Mohammadhasan; Siepmann, J Ilja; Truhlar, Donald G

    2013-01-07

    We present a procedure to calculate ensemble averages, thermodynamic derivatives, and coordinate distributions by effective classical potential methods. In particular, we consider the displaced-points path integral (DPPI) method, which yields exact quantal partition functions and ensemble averages for a harmonic potential and approximate quantal ones for general potentials, and we discuss the implementation of the new procedure in two Monte Carlo simulation codes, one that uses uncorrelated samples to calculate absolute free energies, and another that employs Metropolis sampling to calculate relative free energies. The results of the new DPPI method are compared to those from accurate path integral calculations as well as to results of two other effective classical potential schemes for the case of an isolated water molecule. In addition to the partition function, we consider the heat capacity and expectation values of the energy, the potential energy, the bond angle, and the OH distance. We also consider coordinate distributions. The DPPI scheme performs best among the three effective potential schemes considered and achieves very good accuracy for all of the properties considered. A key advantage of the effective potential schemes is that they display much lower statistical sampling variances than those for accurate path integral calculations. The method presented here shows great promise for including quantum effects in calculations on large systems.

  10. Bound states of the Dirac equation with some physical potentials by the Nikiforov-Uvarov method

    Energy Technology Data Exchange (ETDEWEB)

    Setare, Mohammad R; Haidari, S [Department of Physics, University of Kurdistan, Pasdaran Avenue, Sanandaj (Iran, Islamic Republic of)], E-mail: rezakord@ipm.ir, E-mail: heidary.somayeh@gmail.com

    2010-01-15

    Exact analytical solutions for the s-wave Dirac equation with the reflectionless-type, Rosen-Morse and Manning-Rosen potentials are obtained, under the condition of spin symmetry. We obtained bound state energy eigenvalues and corresponding spinor wave function in the framework of the Nikiforov-Uvarov (NU) method.

  11. Systematic Convergence in Applying Variational Method to Double-Well Potential

    Science.gov (United States)

    Mei, Wai-Ning

    2016-01-01

    In this work, we demonstrate the application of the variational method by computing the ground- and first-excited state energies of a double-well potential. We start with the proper choice of the trial wave functions using optimized parameters, and notice that accurate expectation values in excellent agreement with the numerical results can be…

  12. Methods for the Evaluation of the Bioactivity and Biocontrol Potential of Species of Trichoderma.

    Science.gov (United States)

    Steyaert, Johanna; Hicks, Emily; Kandula, Janaki; Kandula, Diwakar; Alizadeh, Hossein; Braithwaite, Mark; Yardley, Jessica; Mendoza-Mendoza, Artemio; Stewart, Alison

    2016-01-01

    Members of the genus Trichoderma comprise the majority of commercial fungal biocontrol agents of plant diseases. As such, there is a wealth of information available on the analysis of their biocontrol potential and the mechanisms behind their superior abilities. This chapter aims to summarize the most common methods utilized within a Trichoderma biocontrol program for assessing the biological properties of individual strains.

  13. Application of the DC potential drop and the partial unloading methods to fracture mechanics tests

    International Nuclear Information System (INIS)

    Heerens, J.; Schwalbe, K.H.; Hellmann, D.; Knaack, J.; Mueller-Roos, J.

    1985-01-01

    The ability of the DC potential drop method and the partial unloading technique to measure crack growth and to detect initation of crack growth has been investigated using a number of steels and aluminium alloys. It was found that within the range of parameters investigated both of these methods can be recommended for the determination of the R-curve; however, since at small amounts of crack growth the DC potential drop method gave more consistent results it is therefore considered to be superior. The initation values J(0) of J determined by fractography were compared with J(Ic) as obtained by current practice. It was found that J(Ic) is poorly related to initation or to specific amount of crack growth. A modification of the J(Ic) procedure is proposed. Two contacting arrangements of the DC potential drop method were checked for initation detection: one indicates initation by a potential minimum (related to a J value J(min)), the other by the intersection of the R-curve with the blunting line (related to a J value J(int)). (orig.) [de

  14. Ion-step method for surface potential sensing of silicon nanowires

    NARCIS (Netherlands)

    Chen, S.; van Nieuwkasteele, Jan William; van den Berg, Albert; Eijkel, Jan C.T.

    2016-01-01

    This paper presents a novel stimulus-response method for surface potential sensing of silicon nanowire (Si NW) field-effect transistors. When an "ion-step" from low to high ionic strength is given as a stimulus to the gate oxide surface, an increase of double layer capacitance is therefore expected.

  15. Potentiality if Rb-Sr method for dating the argillous sedimentary rocks

    International Nuclear Information System (INIS)

    Thomaz Filho, A.

    1976-01-01

    The potentiality of application Rb-Sr method in argillous sediments, using samples from paleozoic and mesozoic formation in brazilian sedimentaries basin was tested. Physical, chemistry and isotopic analysis of thirty eight samples were made in the laboratories of geochronology Research Center from the University of Sao Paulo. Four isochronic diagrams for the argillous sedimentary rocks were also proposed. (author)

  16. Race and Research Methods Anxiety in an Undergraduate Sample: The Potential Effects of Self-Perception

    Science.gov (United States)

    Eckberg, Deborah A.

    2015-01-01

    This study explores race as a potential predictor of research methods anxiety among a sample of undergraduates. While differences in academic achievement based on race and ethnicity have been well documented, few studies have examined racial differences in anxiety with regard to specific subject matter in undergraduate curricula. This exploratory…

  17. Assessing the marketing potential of communicating corporate social responsibility of a supply chain: method and application

    NARCIS (Netherlands)

    Verhees, F.J.H.M.; Kuipers, A.; Meulenberg, M.T.G.

    2006-01-01

    Abstract This article provides a method to assess the marketing potential of communicating corporate social responsibility of (agricultural) supply chains. The willingness of small firms in agricultural supply chains to make available information about certain dimensions of CSR is measured and

  18. Panel cutting method: new approach to generate panels on a hull in Rankine source potential approximation

    Directory of Open Access Journals (Sweden)

    Hee-Jong Choi

    2011-12-01

    Full Text Available In the present study, a new hull panel generation algorithm, namely panel cutting method, was developed to predict flow phenomena around a ship using the Rankine source potential based panel method, where the iterative method was used to satisfy the nonlinear free surface condition and the trim and sinkage of the ship was taken into account. Numerical computations were performed to investigate the validity of the proposed hull panel generation algorithm for Series 60 (CB=0.60 hull and KRISO container ship (KCS, a container ship designed by Maritime and Ocean Engineering Research Institute (MOERI. The computational results were validated by comparing with the existing experimental data.

  19. Panel cutting method: new approach to generate panels on a hull in Rankine source potential approximation

    Science.gov (United States)

    Choi, Hee-Jong; Chun, Ho-Hwan; Park, Il-Ryong; Kim, Jin

    2011-12-01

    In the present study, a new hull panel generation algorithm, namely panel cutting method, was developed to predict flow phenomena around a ship using the Rankine source potential based panel method, where the iterative method was used to satisfy the nonlinear free surface condition and the trim and sinkage of the ship was taken into account. Numerical computations were performed to investigate the validity of the proposed hull panel generation algorithm for Series 60 (CB=0.60) hull and KRISO container ship (KCS), a container ship designed by Maritime and Ocean Engineering Research Institute (MOERI). The computational results were validated by comparing with the existing experimental data.

  20. Pseudo-potential method for taking into account the Pauli principle in cluster systems

    International Nuclear Information System (INIS)

    Krasnopol'skii, V.M.; Kukulin, V.I.

    1975-01-01

    In order to take account of the Pauli principle in cluster systems (such as 3α, α + α + n) a convenient method of renormalization of the cluster-cluster deep attractive potentials with forbidden states is suggested. The renormalization consists of adding projectors upon the occupied states with an infinite coupling constant to the initial deep potential which means that we pass to pseudo-potentials. The pseudo-potential approach in projecting upon the noneigenstates is shown to be equivalent to the orthogonality condition model of Saito et al. The orthogonality of the many-particle wave function to the forbidden states of each two-cluster sub-system is clearly demonstrated

  1. Basal and prism dislocation cores in magnesium: comparison of first-principles and embedded-atom-potential methods predictions

    International Nuclear Information System (INIS)

    Yasi, J A; Nogaret, T; Curtin, W A; Trinkle, D R; Qi, Y; Hector, L G Jr

    2009-01-01

    The core structures of screw and edge dislocations on the basal and prism planes in Mg, and the associated gamma surfaces, were studied using an ab initio method and the embedded-atom-method interatomic potentials developed by Sun et al and Liu et al. The ab initio calculations predict that the basal plane dislocations dissociate into partials split by 16.7 Å (edge) and 6.3 Å (screw), as compared with 14.3 Å and 12.7 Å (Sun and Liu edge), and 6.3 Å and 1.4 Å (Sun and Liu screw), with the Liu screw dislocation being metastable. In the prism plane, the screw and edge cores are compact and the edge core structures are all similar, while ab initio does not predict a stable prismatic screw in stress-free conditions. These results are qualitatively understood through an examination of the gamma surfaces for interplanar sliding on the basal and prism planes. The Peierls stresses at T = 0 K for basal slip are a few megapascals for the Sun potential, in agreement with experiments, but are ten times larger for the Liu potential. The Peierls stresses for prism slip are 10–40 MPa for both potentials. Overall, the dislocation core structures from ab initio are well represented by the Sun potential in all cases while the Liu potential shows some notable differences. These results suggest that the Sun potential is preferable for studying other dislocations in Mg, particularly the (c + a) dislocations, for which the core structures are much larger and not accessible by ab initio methods

  2. Is Drug Use Related to the Choice of Potentially More Harmful Methods in Suicide Attempts?

    Directory of Open Access Journals (Sweden)

    Dartiu Xavier Da Silveira

    2014-01-01

    Full Text Available Objective To identify whether drug abuse is a risk factor for potentially more harmful methods of suicide attempts that could predict suicide completion in the future. Methods: The study involved the assessment of 86 patients who attempted suicide and who were admitted to the emergency ward of a Southwestern Brazilian general hospital. Results: Most patients were women (84.9%, young adults (30.53 ± 10.4 years, and single (61.6%. Recent drug use was reported by 53.5%, and 25.6% reported the use of drugs during the 24-hour period immediately before the suicide attempt. Most patients (75.6% ingested pills when attempting suicide–-a method considered potentially less harmful. Hanging, jumping, gas inhaling, and wrist cutting accounted for 22.2% of the attempts. Considering dual diagnoses, 54.7% presented with a depressive disorder, 8.1% with a disorder on the impulse control spectrum, and 26.7% reported an associated clinical condition. Recent drug use was predictive of the severity of the suicide attempt, as it was reported by 81% of those who engaged in more harmful attempts and by 46.2% of those who used less harmful methods ( P < 0.01; odds ratio = 4.96; confidence interval: 1.5–16.4. Conclusion: The identified variables associated with the use of potentially more harmful methods in suicide attempts were gender (male, presence of an impulsive control disorder, and recent use of psychoactive drugs.

  3. Synaptic neurochemistry: Potential targets for the development of new tracer imaging methods

    International Nuclear Information System (INIS)

    Frey, K.A.

    1991-01-01

    Radiotracer techniques for measuring biochemical and pharmacologic processes unique to the synapse and to chemically defined neuronal populations are now under investigation. These methods make use of neuronal biochemical specializations determined by invasive animal experiments and confirmed by human biopsy and autopsy. Early investigators focused on determination of neurotransmitter receptors. More recently, attention has turned to evaluation of presynaptic markers such as steps in neurotransmitter synthesis, storage and degradation, and to the potential evaluation of new postsynaptic markers, including chemical second-messenger activities and receptor-grated ion channel distributions. In this review, synaptic neurochemistry is presented with attention to potential radiotracer imaging methods. Strategies for selecting and applying neuropharmacologic methods to disorders of the human brain are outlined. The methodological requirements of new radiotracer imaging techniques are summarized according to their desired application. Finally, distinctions between in vitro and in vivo measurements of these processes are outlined, along with strategies for detecting such differences

  4. The effect of empirical potential functions on modeling of amorphous carbon using molecular dynamics method

    International Nuclear Information System (INIS)

    Li, Longqiu; Xu, Ming; Song, Wenping; Ovcharenko, Andrey; Zhang, Guangyu; Jia, Ding

    2013-01-01

    Empirical potentials have a strong effect on the hybridization and structure of amorphous carbon and are of great importance in molecular dynamics (MD) simulations. In this work, amorphous carbon at densities ranging from 2.0 to 3.2 g/cm 3 was modeled by a liquid quenching method using Tersoff, 2nd REBO, and ReaxFF empirical potentials. The hybridization, structure and radial distribution function G(r) of carbon atoms were analyzed as a function of the three potentials mentioned above. The ReaxFF potential is capable to model the change of the structure of amorphous carbon and MD results are in a good agreement with experimental results and density function theory (DFT) at low density of 2.6 g/cm 3 and below. The 2nd REBO potential can be used when amorphous carbon has a very low density of 2.4 g/cm 3 and below. Considering the computational efficiency, the Tersoff potential is recommended to model amorphous carbon at a high density of 2.6 g/cm 3 and above. In addition, the influence of the quenching time on the hybridization content obtained with the three potentials is discussed.

  5. Transforming high-dimensional potential energy surfaces into sum-of-products form using Monte Carlo methods

    Science.gov (United States)

    Schröder, Markus; Meyer, Hans-Dieter

    2017-08-01

    We propose a Monte Carlo method, "Monte Carlo Potfit," for transforming high-dimensional potential energy surfaces evaluated on discrete grid points into a sum-of-products form, more precisely into a Tucker form. To this end we use a variational ansatz in which we replace numerically exact integrals with Monte Carlo integrals. This largely reduces the numerical cost by avoiding the evaluation of the potential on all grid points and allows a treatment of surfaces up to 15-18 degrees of freedom. We furthermore show that the error made with this ansatz can be controlled and vanishes in certain limits. We present calculations on the potential of HFCO to demonstrate the features of the algorithm. To demonstrate the power of the method, we transformed a 15D potential of the protonated water dimer (Zundel cation) in a sum-of-products form and calculated the ground and lowest 26 vibrationally excited states of the Zundel cation with the multi-configuration time-dependent Hartree method.

  6. An auto-triggered anode potential lowering method on increase of after-pulses in a GM-counter

    International Nuclear Information System (INIS)

    Igarashi, Ryuji; Narita, Yuichi

    1982-01-01

    The number of after-pulses generated in an organic quenching GM-counter depends on the pulsed radiation intensity, and it can be usable for the intensity measurement. The increase of the number of after-pulse occurrence (occurring rate) per one exposure to pulsed radiation improves the efficiency in intensity measurement, and is effective to the measurement in low intensity region. The attempt to increase the number of after-pulse factors, to hold those in a GM-counter for more than the dead time and further to improve the after-pulse yield is the presently reported auto-triggered anode potential lowering method. In this report, the experimental apparatus and its procedure are described, and the experimental results about the dependence of after-pulse occurring rate are described on the anode potential lowering duration, on the lowered anode potential, on the high anode potential, and on the intensity of pulsed X-ray. The after-pulse occurring rate by this method showed the dependence on radiation intensity in the range from 4.5 x 10 -4 to 1.1 x 10 -2 mu R/burst, and the occurrence rate can be increased up to about 40 times as much as the mode to lower anode potential only during exposure in this range. (Wakatsuki, Y.)

  7. A direct current potential drop method for evaluating oxide film thickness formed in high-temperature water

    International Nuclear Information System (INIS)

    Anzai, Hideya; Ishibashi, Ryo; Saka, Masumi

    2016-01-01

    To establish an evaluation technique for oxide film thickness in-situ, the applicability of a four-point-probe direct current potential drop method is discussed in this study. Several samples of JIS SUS316L stainless steel with different oxide film thickness were prepared after immersing them in oxygenated pure water at 288°C for different periods. The oxide film thickness was measured by cross sectional observation using a transmission electron microscope. Potential drop on the oxide surface was measured every second during an acquisition period of about 20 s while a constant current was being injected into the sample simultaneously. This kind of measurement was repeatedly carried out at several arbitrary contact positions on the surface of the same sample. The measurement results showed that the potential drop slightly changed during the acquisition period and the tendency varied at the different contact positions. Multiple measurements at different contact positions revealed that the tendency could be categorized into two general types: the decreasing potential drop and the increasing potential drop, defined by the overall trend of the potential drop during the acquisition time. It was found that the ratio of contact positions with a decreasing potential drop tendency to all the contact positions of measurement tended to increase as applied current increased. This tendency depended on the oxide film thickness. The threshold value of applied current was found to correlate well with the oxide film thickness when the occurrence rate of decreasing potential drop ranged from 70 to 90% showing the best correlation at 70%. (author)

  8. Evaluating the Level of the Export-Import Potential of Industrial Enterprises: Methodical Support

    Directory of Open Access Journals (Sweden)

    Otenko Vasyl I.

    2017-04-01

    Full Text Available The article provides a detailed description of the methodical support for evaluating the level of development and use of the export-import potential of industrial enterprises. The place of evaluation in the system of management of the enterprise’s export-import potential (EIPE, as well as its conceptual content have been defined. An implementation of the proposed methodical support for evaluation of the EIPE has been displayed on the example of the major industrial enterprises of the city of Kharkiv. It has been substantiated that the objectivity and effectiveness of evaluation of the level of export-import potential of industrial enterprises is methodically ensured by: the system of partial indicators allowing for regular monitoring and diagnosing tendencies in the status and the use of the EIPE; the analytical tool – i.e. cluster, factor, and canonical analyzes to identify causal relationships in the components of potential and to determine the indicators of impact; the development and use of the EIPE, as well as the evaluation procedure itself, which is recommended for implementation in accordance with the appropriate stages.

  9. Methods for evaluating potential impacts to aquatic receptors at a metal-contaminated superfund site

    International Nuclear Information System (INIS)

    Hattemer-Frey, H.A.; Quinlan, R.E.; Krieger, G.R.

    1994-01-01

    An ecological risk assessment (ERA) was conducted for a metals mining site in the midwestern United States. Chemicals of potential concern were shown to be heavy metals associated with mine wastes and with base metal ore deposits that are characteristic of this area. Environmental receptors were identified by considering the relevant exposure pathways and the potential or known occurrence of species exposed via those pathways. Selection of key receptor species was designed to minimize the possibility that other species would be more exposed than the key species themselves and to include representation of sensitive organisms present at the subsites. In addition, an EPA-approved method was use to developed site-specific ambient water quality criteria. Ecological impacts were assessed using two complimentary approaches. First, potential chronic impacts were assessed by applying the toxicity quotient approach (i.e., a comparison of the measured concentration of site-related metals in surface water with available health-based criteria). Secondly, semi-quantitative comparative ecology data were used to obtain to provide a direct measure of impacts to key species. Results from these two approaches were used to provide a direct measure of impacts to key species. Results from these two approaches were used to obtain a realistic picture of actual and potential risks associated with exposure by key species to mining-related metals. This paper discusses the uncertainties associated with both methods and presents a method for interpreting disparate and sometimes confusing ecological data using the results from a case study

  10. Comparative studies on structural properties and antimicrobial potential of spinel ferrite nanoparticles synthesized using various methods

    Science.gov (United States)

    Baraliya, Jagdish D.; Rakhashiya, Purvi M.; Patel, Pooja P.; Thaker, Vrinda S.; Joshi, Hiren H.

    2017-05-01

    In this study, novel multifunctional magnetic iron-based nanoparticles (CoFe2O4) coated with silica, silica-DEG (diethylene glycol), PEG (polyethylene glycol) were synthesized using Auto Combustion Method (ACM), Co-precipitation Method (COPM), Citrate Precursor Method (CPM), Flash Combustion Method (FCM). These spinel ferrite nanoparticles also contain very high antibacterial properties to fulfill the requirements of a drug delivery system so that the antibiotic concentration could be minimized. A potential delivery system could be based on a ferromagnetic fluid. The effects of various preparation methods on the physical properties of the nanoparticles were examined. The nanoparticles were also tested against four human pathogenic bacteria (Gram negative E.coli, P. aeruginosa, Gram positive S. aureus, S. pyogenus) and two fungi (C. albicans, A.niger). It was revealed that a nanoparticle has strong antibacterial activity as compared to antifungal. Further, Gram positive bacteria are more affected than Gram negative bacteria. It was also clear that different methods of coating have great influence on the antimicrobial properties. It was observed that these nanoparticles have significantly different but potentially very high antimicrobial activities against the tested organisms than found elsewhere by other nanoparticles on the same organisms.

  11. Measurements of fatigue crack length at elevated temperature by D. C. electrical potential method

    International Nuclear Information System (INIS)

    Matsumoto, Masakatsu; Yamauchi, Isamu; Kodaira, Tsuneo

    1982-07-01

    The direct current (d.c.) electrical potential method was used to automatically and continuously measure the crack length in cyclic crack growth test at elevated temperature. This report describes some results concerning the calibration curves, i.e. the relation between electrical potential change and amount of crack extention, using SUS 304 and 2 1/4Cr-1Mo steels. It can be concluded that the measurements of fatigue crack length is possible even at elevated temperature as well as at room temperature with the equivalent accuracy. (author)

  12. An Excel‐based implementation of the spectral method of action potential alternans analysis

    Science.gov (United States)

    Pearman, Charles M.

    2014-01-01

    Abstract Action potential (AP) alternans has been well established as a mechanism of arrhythmogenesis and sudden cardiac death. Proper interpretation of AP alternans requires a robust method of alternans quantification. Traditional methods of alternans analysis neglect higher order periodicities that may have greater pro‐arrhythmic potential than classical 2:1 alternans. The spectral method of alternans analysis, already widely used in the related study of microvolt T‐wave alternans, has also been used to study AP alternans. Software to meet the specific needs of AP alternans analysis is not currently available in the public domain. An AP analysis tool is implemented here, written in Visual Basic for Applications and using Microsoft Excel as a shell. This performs a sophisticated analysis of alternans behavior allowing reliable distinction of alternans from random fluctuations, quantification of alternans magnitude, and identification of which phases of the AP are most affected. In addition, the spectral method has been adapted to allow detection and quantification of higher order regular oscillations. Analysis of action potential morphology is also performed. A simple user interface enables easy import, analysis, and export of collated results. PMID:25501439

  13. An Excel-based implementation of the spectral method of action potential alternans analysis.

    Science.gov (United States)

    Pearman, Charles M

    2014-12-01

    Action potential (AP) alternans has been well established as a mechanism of arrhythmogenesis and sudden cardiac death. Proper interpretation of AP alternans requires a robust method of alternans quantification. Traditional methods of alternans analysis neglect higher order periodicities that may have greater pro-arrhythmic potential than classical 2:1 alternans. The spectral method of alternans analysis, already widely used in the related study of microvolt T-wave alternans, has also been used to study AP alternans. Software to meet the specific needs of AP alternans analysis is not currently available in the public domain. An AP analysis tool is implemented here, written in Visual Basic for Applications and using Microsoft Excel as a shell. This performs a sophisticated analysis of alternans behavior allowing reliable distinction of alternans from random fluctuations, quantification of alternans magnitude, and identification of which phases of the AP are most affected. In addition, the spectral method has been adapted to allow detection and quantification of higher order regular oscillations. Analysis of action potential morphology is also performed. A simple user interface enables easy import, analysis, and export of collated results. © 2014 The Author. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.

  14. Show-Bix &

    DEFF Research Database (Denmark)

    2014-01-01

    The anti-reenactment 'Show-Bix &' consists of 5 dias projectors, a dial phone, quintophonic sound, and interactive elements. A responsive interface will enable the Dias projectors to show copies of original dias slides from the Show-Bix piece ”March på Stedet”, 265 images in total. The copies are...

  15. Multilevel fast multipole method based on a potential formulation for 3D electromagnetic scattering problems.

    Science.gov (United States)

    Fall, Mandiaye; Boutami, Salim; Glière, Alain; Stout, Brian; Hazart, Jerome

    2013-06-01

    A combination of the multilevel fast multipole method (MLFMM) and boundary element method (BEM) can solve large scale photonics problems of arbitrary geometry. Here, MLFMM-BEM algorithm based on a scalar and vector potential formulation, instead of the more conventional electric and magnetic field formulations, is described. The method can deal with multiple lossy or lossless dielectric objects of arbitrary geometry, be they nested, in contact, or dispersed. Several examples are used to demonstrate that this method is able to efficiently handle 3D photonic scatterers involving large numbers of unknowns. Absorption, scattering, and extinction efficiencies of gold nanoparticle spheres, calculated by the MLFMM, are compared with Mie's theory. MLFMM calculations of the bistatic radar cross section (RCS) of a gold sphere near the plasmon resonance and of a silica coated gold sphere are also compared with Mie theory predictions. Finally, the bistatic RCS of a nanoparticle gold-silver heterodimer calculated with MLFMM is compared with unmodified BEM calculations.

  16. A fluorescence high throughput screening method for the detection of reactive electrophiles as potential skin sensitizers

    Energy Technology Data Exchange (ETDEWEB)

    Avonto, Cristina; Chittiboyina, Amar G. [National Center for Natural Products Research, Research Institute of Pharmaceutical Sciences, School of Pharmacy, The University of Mississippi, University, MS 38677 (United States); Rua, Diego [The Center for Food Safety and Applied Nutrition, US Food and Drug Administration, College Park, MD 20740 (United States); Khan, Ikhlas A., E-mail: ikhan@olemiss.edu [National Center for Natural Products Research, Research Institute of Pharmaceutical Sciences, School of Pharmacy, The University of Mississippi, University, MS 38677 (United States); Division of Pharmacognosy, Department of BioMolecular Sciences, School of Pharmacy, The University of Mississippi, University, MS 38677 (United States)

    2015-12-01

    Skin sensitization is an important toxicological end-point in the risk assessment of chemical allergens. Because of the complexity of the biological mechanisms associated with skin sensitization, integrated approaches combining different chemical, biological and in silico methods are recommended to replace conventional animal tests. Chemical methods are intended to characterize the potential of a sensitizer to induce earlier molecular initiating events. The presence of an electrophilic mechanistic domain is considered one of the essential chemical features to covalently bind to the biological target and induce further haptenation processes. Current in chemico assays rely on the quantification of unreacted model nucleophiles after incubation with the candidate sensitizer. In the current study, a new fluorescence-based method, ‘HTS-DCYA assay’, is proposed. The assay aims at the identification of reactive electrophiles based on their chemical reactivity toward a model fluorescent thiol. The reaction workflow enabled the development of a High Throughput Screening (HTS) method to directly quantify the reaction adducts. The reaction conditions have been optimized to minimize solubility issues, oxidative side reactions and increase the throughput of the assay while minimizing the reaction time, which are common issues with existing methods. Thirty-six chemicals previously classified with LLNA, DPRA or KeratinoSens™ were tested as a proof of concept. Preliminary results gave an estimated 82% accuracy, 78% sensitivity, 90% specificity, comparable to other in chemico methods such as Cys-DPRA. In addition to validated chemicals, six natural products were analyzed and a prediction of their sensitization potential is presented for the first time. - Highlights: • A novel fluorescence-based method to detect electrophilic sensitizers is proposed. • A model fluorescent thiol was used to directly quantify the reaction products. • A discussion of the reaction workflow

  17. A fluorescence high throughput screening method for the detection of reactive electrophiles as potential skin sensitizers

    International Nuclear Information System (INIS)

    Avonto, Cristina; Chittiboyina, Amar G.; Rua, Diego; Khan, Ikhlas A.

    2015-01-01

    Skin sensitization is an important toxicological end-point in the risk assessment of chemical allergens. Because of the complexity of the biological mechanisms associated with skin sensitization, integrated approaches combining different chemical, biological and in silico methods are recommended to replace conventional animal tests. Chemical methods are intended to characterize the potential of a sensitizer to induce earlier molecular initiating events. The presence of an electrophilic mechanistic domain is considered one of the essential chemical features to covalently bind to the biological target and induce further haptenation processes. Current in chemico assays rely on the quantification of unreacted model nucleophiles after incubation with the candidate sensitizer. In the current study, a new fluorescence-based method, ‘HTS-DCYA assay’, is proposed. The assay aims at the identification of reactive electrophiles based on their chemical reactivity toward a model fluorescent thiol. The reaction workflow enabled the development of a High Throughput Screening (HTS) method to directly quantify the reaction adducts. The reaction conditions have been optimized to minimize solubility issues, oxidative side reactions and increase the throughput of the assay while minimizing the reaction time, which are common issues with existing methods. Thirty-six chemicals previously classified with LLNA, DPRA or KeratinoSens™ were tested as a proof of concept. Preliminary results gave an estimated 82% accuracy, 78% sensitivity, 90% specificity, comparable to other in chemico methods such as Cys-DPRA. In addition to validated chemicals, six natural products were analyzed and a prediction of their sensitization potential is presented for the first time. - Highlights: • A novel fluorescence-based method to detect electrophilic sensitizers is proposed. • A model fluorescent thiol was used to directly quantify the reaction products. • A discussion of the reaction workflow

  18. Simulating Ice Shelf Response to Potential Triggers of Collapse Using the Material Point Method

    Science.gov (United States)

    Huth, A.; Smith, B. E.

    2017-12-01

    Weakening or collapse of an ice shelf can reduce the buttressing effect of the shelf on its upstream tributaries, resulting in sea level rise as the flux of grounded ice into the ocean increases. Here we aim to improve sea level rise projections by developing a prognostic 2D plan-view model that simulates the response of an ice sheet/ice shelf system to potential triggers of ice shelf weakening or collapse, such as calving events, thinning, and meltwater ponding. We present initial results for Larsen C. Changes in local ice shelf stresses can affect flow throughout the entire domain, so we place emphasis on calibrating our model to high-resolution data and precisely evolving fracture-weakening and ice geometry throughout the simulations. We primarily derive our initial ice geometry from CryoSat-2 data, and initialize the model by conducting a dual inversion for the ice viscosity parameter and basal friction coefficient that minimizes mismatch between modeled velocities and velocities derived from Landsat data. During simulations, we implement damage mechanics to represent fracture-weakening, and track ice thickness evolution, grounding line position, and ice front position. Since these processes are poorly represented by the Finite Element Method (FEM) due to mesh resolution issues and numerical diffusion, we instead implement the Material Point Method (MPM) for our simulations. In MPM, the ice domain is discretized into a finite set of Lagrangian material points that carry all variables and are tracked throughout the simulation. Each time step, information from the material points is projected to a Eulerian grid where the momentum balance equation (shallow shelf approximation) is solved similarly to FEM, but essentially treating the material points as integration points. The grid solution is then used to determine the new positions of the material points and update variables such as thickness and damage in a diffusion-free Lagrangian frame. The grid does not store

  19. A method to analyze the potential of solar cells on roofs and facades in the Netherlands

    International Nuclear Information System (INIS)

    Van den Haspel, B.; Winter, R.; Corten, F.

    1993-06-01

    The purpose of the study on the title subject is to compile a database in which the surfaces of roofs and facades in the Netherlands can be characterized and calculated in order to analyze the technical potential of photovoltaic systems. The potential can be analyzed by deducting a production-cost curve. The database can be used for national studies, as well as for studies on a provincial level, while data are compiled per province. A brief summary is given of studies in other countries and one study in the Netherlands on the estimation of the potential. An overview is given of the available databases in the Netherlands which can be used in developing the roof and facade surface database. Finally, the method is described by which the most relevant data of surfaces and facades of buildings in the Netherlands can be compiled, put into a database and applied. 3 figs., 3 tabs., 1 appendix, 19 refs

  20. Standard test method for measurement of corrosion potentials of Aluminum alloys

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1997-01-01

    1.1 This test method covers a procedure for measurement of the corrosion potential (see Note 1) of an aluminum alloy in an aqueous solution of sodium chloride with enough hydrogen peroxide added to provide an ample supply of cathodic reactant. Note 1—The corrosion potential is sometimes referred to as the open-circuit solution or rest potential. 1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  1. Current matrix element in HAL QCD's wavefunction-equivalent potential method

    Science.gov (United States)

    Watanabe, Kai; Ishii, Noriyoshi

    2018-04-01

    We give a formula to calculate a matrix element of a conserved current in the effective quantum mechanics defined by the wavefunction-equivalent potentials proposed by the HAL QCD collaboration. As a first step, a non-relativistic field theory with two-channel coupling is considered as the original theory, with which a wavefunction-equivalent HAL QCD potential is obtained in a closed analytic form. The external field method is used to derive the formula by demanding that the result should agree with the original theory. With this formula, the matrix element is obtained by sandwiching the effective current operator between the left and right eigenfunctions of the effective Hamiltonian associated with the HAL QCD potential. In addition to the naive one-body current, the effective current operator contains an additional two-body term emerging from the degrees of freedom which has been integrated out.

  2. Is Drug Use Related to the Choice of Potentially More Harmful Methods in Suicide Attempts?

    OpenAIRE

    da Silveira, Dartiu Xavier; Fidalgo, Thiago Marques; Di Pietro, Monica; Santos, Jair Guilherme; Oliveira, Leonardo Q

    2014-01-01

    Objective To identify whether drug abuse is a risk factor for potentially more harmful methods of suicide attempts that could predict suicide completion in the future. Methods: The study involved the assessment of 86 patients who attempted suicide and who were admitted to the emergency ward of a Southwestern Brazilian general hospital. Results: Most patients were women (84.9%), young adults (30.53 ± 10.4 years), and single (61.6%). Recent drug use was reported by 53.5%, and 25.6% reported the...

  3. A study of potential energy curves from the model space quantum Monte Carlo method

    Energy Technology Data Exchange (ETDEWEB)

    Ohtsuka, Yuhki; Ten-no, Seiichiro, E-mail: tenno@cs.kobe-u.ac.jp [Department of Computational Sciences, Graduate School of System Informatics, Kobe University, Nada-ku, Kobe 657-8501 (Japan)

    2015-12-07

    We report on the first application of the model space quantum Monte Carlo (MSQMC) to potential energy curves (PECs) for the excited states of C{sub 2}, N{sub 2}, and O{sub 2} to validate the applicability of the method. A parallel MSQMC code is implemented with the initiator approximation to enable efficient sampling. The PECs of MSQMC for various excited and ionized states are compared with those from the Rydberg-Klein-Rees and full configuration interaction methods. The results indicate the usefulness of MSQMC for precise PECs in a wide range obviating problems concerning quasi-degeneracy.

  4. An improved potential drop method for measuring and monitoring defects in metallic structures

    International Nuclear Information System (INIS)

    Oppermann, W.; Keller, H.P.

    1993-01-01

    In the developed form described the direct current potential drop method is a reliable and relatively accurate procedure for the measuring and surveillance of surface cracks in metallic materials. There are also significant possibilities in practice of surveying cracks on the inaccessible side of the structure. The basis for the improvement in accuracy, in particular for short cracks, is firstly an improved measuring technique and secondly calibration curves determined using an electrolytic tank. Practical experience gained in conventional plants is to date positive. The opportunity exists of benefitting from the advantages that would be brought about by an increased use of the potential drop method in plant surveillance. In nuclear plants specifically this would achieve a reduction in the testing personnel's exposure to radiation. (orig.)

  5. Study on evaluation method for potential effect of natural phenomena on a HLW disposal system

    International Nuclear Information System (INIS)

    Kawamura, Makoto; Makino, Hitoshi; Umeda, Koji; Osawa, Hideaki; Seo, Toshihiro; Ishimaru, Tsuneaki

    2005-01-01

    Evaluation for the potential effect of natural phenomena on a HLW disposal system is an important issue in safety assessment. A scenario construction method for the effects on a HLW disposal system condition and performance has been developed for two purposes: the first being effective elicitation and organization of information from investigators of natural phenomena and performance assessor and the second being, maintenance of traceability of scenario construction processes with suitable records. In this method, a series of works to construct scenarios is divided into pieces to facilitate and to elicit the features of potential effect of natural phenomena on a HLW disposal system and is organized to create reasonable scenarios with consistency, traceability and adequate conservativeness within realistic view. (author)

  6. Microencapsulation as a novel delivery method for the potential antidiabetic drug, Probucol

    Directory of Open Access Journals (Sweden)

    Mooranian A

    2014-09-01

    Full Text Available Armin Mooranian,1 Rebecca Negrulj,1 Nigel Chen-Tan,2 Hesham S Al-Sallami,3 Zhongxiang Fang,4 TK Mukkur,5 Momir Mikov,6,7 Svetlana Golocorbin-Kon,6,7 Marc Fakhoury,8 Gerald F Watts,9 Vance Matthews,10 Frank Arfuso,5 Hani Al-Salami1 1Biotechnology and Drug Development Research Laboratory School of Pharmacy, Curtin Health Innovation Research Institute, Biosciences Research Precinct, Curtin University, Perth, Western Australia, Australia; 2Faculty of Science and Engineering, Curtin University, Perth, Western Australia, Australia; 3School of Pharmacy, University of Otago, Dunedin, New Zealand; 4School of Public Health, Curtin University, Perth, Western Australia, Australia; 5Curtin Health Innovation Research Institute, Biosciences Research Precinct, School of Biomedical Science, Curtin University, Perth, Western Australia, Australia; 6Department of Pharmacology, Toxicology and Clinical Pharmacology, Faculty of Medicine, University of Novi Sad, Serbia; 7Department of Pharmacy, Faculty of Medicine, University of Novi Sad, Serbia; 8Faculty of Medicine, University of Montreal, Montreal, Quebec, Canada; 9School of Medicine and Pharmacology, Royal Perth Hospital, University of Western Australia; 10Laboratory for Metabolic Dysfunction, UWA Centre for Medical Research, Harry Perkins Institute of Medical Research, Perth, Western Australia, Australia Introduction: In previous studies, we successfully designed complex multicompartmental microcapsules as a platform for the oral targeted delivery of lipophilic drugs in type 2 diabetes (T2D. Probucol (PB is an antihyperlipidemic and antioxidant drug with the potential to show benefits in T2D. We aimed to create a novel microencapsulated formulation of PB and to examine the shape, size, and chemical, thermal, and rheological properties of these microcapsules in vitro. Method: Microencapsulation was carried out using the Büchi-based microencapsulating system developed in our laboratory. Using the polymer, sodium

  7. Multilayer airdrome pavement modeling on the base of numeically-analythical method of potential

    Directory of Open Access Journals (Sweden)

    О.М. Шевченко

    2004-04-01

    Full Text Available  There are problems of the take into account the multilayered foundation distributive properties which are ignored in the elementary case of Winkler foundation at calculation of constructions on the elastic foundation. In article the apparatus realization of numerically-analytical method of potential for a problem about stress and strain state analysis is considered for the multilayered pavement consisting from two isotropic layers with a separating layer between.

  8. Numerical soliton-like solutions of the potential Kadomtsev-Petviashvili equation by the decomposition method

    International Nuclear Information System (INIS)

    Kaya, Dogan; El-Sayed, Salah M.

    2003-01-01

    In this Letter we present an Adomian's decomposition method (shortly ADM) for obtaining the numerical soliton-like solutions of the potential Kadomtsev-Petviashvili (shortly PKP) equation. We will prove the convergence of the ADM. We obtain the exact and numerical solitary-wave solutions of the PKP equation for certain initial conditions. Then ADM yields the analytic approximate solution with fast convergence rate and high accuracy through previous works. The numerical solutions are compared with the known analytical solutions

  9. Method for Estimating Evaporative Potential (IM/CLO) from ASTM Standard Single Wind Velocity Measures

    Science.gov (United States)

    2016-08-10

    IM/CLO) FROM ASTM STANDARD SINGLE WIND VELOCITY MEASURES DISCLAIMER The opinions or assertions contained herein are the private views of the...USARIEM TECHNICAL REPORT T16-14 METHOD FOR ESTIMATING EVAPORATIVE POTENTIAL (IM/CLO) FROM ASTM STANDARD SINGLE WIND VELOCITY... ASTM STANDARD SINGLE WIND VELOCITY MEASURES Adam W. Potter Biophysics and Biomedical Modeling Division U.S. Army Research Institute of Environmental

  10. Equation of motion method in appearance potential spectra of simple metals

    International Nuclear Information System (INIS)

    Tay, G.

    2004-01-01

    Full Text. The equation of motion method is applied to function Tk 1 K 2 K 3 K 4 which describes, the propagation of two particles in the presence of the core hole. Neglecting final state interactions and assuming constant matrix elements, X-ray yield and the associated appearance potential spectrum is found to depend on the convolution of the empty density of states above the Fermi level of the metal. (author)

  11. An Improved Isotropic Periodic Sum Method That Uses Linear Combinations of Basis Potentials

    KAUST Repository

    Takahashi, Kazuaki Z.

    2012-11-13

    Isotropic periodic sum (IPS) is a technique that calculates long-range interactions differently than conventional lattice sum methods. The difference between IPS and lattice sum methods lies in the shape and distribution of remote images for long-range interaction calculations. The images used in lattice sum calculations are identical to those generated from periodic boundary conditions and are discretely positioned at lattice points in space. The images for IPS calculations are "imaginary", which means they do not explicitly exist in a simulation system and are distributed isotropically and periodically around each particle. Two different versions of the original IPS method exist. The IPSn method is applied to calculations for point charges, whereas the IPSp method calculates polar molecules. However, both IPSn and IPSp have their advantages and disadvantages in simulating bulk water or water-vapor interfacial systems. In bulk water systems, the cutoff radius effect of IPSn strongly affects the configuration, whereas IPSp does not provide adequate estimations of water-vapor interfacial systems unless very long cutoff radii are used. To extend the applicability of the IPS technique, an improved IPS method, which has better accuracy in both homogeneous and heterogeneous systems has been developed and named the linear-combination-based isotropic periodic sum (LIPS) method. This improved IPS method uses linear combinations of basis potentials. We performed molecular dynamics (MD) simulations of bulk water and water-vapor interfacial systems to evaluate the accuracy of the LIPS method. For bulk water systems, the LIPS method has better accuracy than IPSn in estimating thermodynamic and configurational properties without the countercharge assumption, which is used for IPSp. For water-vapor interfacial systems, LIPS has better accuracy than IPSp and properly estimates thermodynamic and configurational properties. In conclusion, the LIPS method can successfully estimate

  12. An Improved Isotropic Periodic Sum Method That Uses Linear Combinations of Basis Potentials

    KAUST Repository

    Takahashi, Kazuaki Z.; Narumi, Tetsu; Suh, Donguk; Yasuoka, Kenji

    2012-01-01

    Isotropic periodic sum (IPS) is a technique that calculates long-range interactions differently than conventional lattice sum methods. The difference between IPS and lattice sum methods lies in the shape and distribution of remote images for long-range interaction calculations. The images used in lattice sum calculations are identical to those generated from periodic boundary conditions and are discretely positioned at lattice points in space. The images for IPS calculations are "imaginary", which means they do not explicitly exist in a simulation system and are distributed isotropically and periodically around each particle. Two different versions of the original IPS method exist. The IPSn method is applied to calculations for point charges, whereas the IPSp method calculates polar molecules. However, both IPSn and IPSp have their advantages and disadvantages in simulating bulk water or water-vapor interfacial systems. In bulk water systems, the cutoff radius effect of IPSn strongly affects the configuration, whereas IPSp does not provide adequate estimations of water-vapor interfacial systems unless very long cutoff radii are used. To extend the applicability of the IPS technique, an improved IPS method, which has better accuracy in both homogeneous and heterogeneous systems has been developed and named the linear-combination-based isotropic periodic sum (LIPS) method. This improved IPS method uses linear combinations of basis potentials. We performed molecular dynamics (MD) simulations of bulk water and water-vapor interfacial systems to evaluate the accuracy of the LIPS method. For bulk water systems, the LIPS method has better accuracy than IPSn in estimating thermodynamic and configurational properties without the countercharge assumption, which is used for IPSp. For water-vapor interfacial systems, LIPS has better accuracy than IPSp and properly estimates thermodynamic and configurational properties. In conclusion, the LIPS method can successfully estimate

  13. Design of potentially active ligands for SH2 domains by molecular modeling methods

    Directory of Open Access Journals (Sweden)

    Hurmach V. V.

    2014-07-01

    Full Text Available Search for new chemical structures possessing specific biological activity is a complex problem that needs the use of the latest achievements of molecular modeling technologies. It is well known that SH2 domains play a major role in ontogenesis as intermediaries of specific protein-protein interactions. Aim. Developing an algorithm to investigate the properties of SH2 domain binding, search for new potential active compounds for the whole SH2 domains class. Methods. In this paper, we utilize a complex of computer modeling methods to create a generic set of potentially active compounds targeting universally at the whole class of SH2 domains. A cluster analysis of all available three-dimensional structures of SH2 domains was performed and general pharmacophore models were formulated. The models were used for virtual screening of collection of drug-like compounds provided by Enamine Ltd. Results. The design technique for library of potentially active compounds for SH2 domains class was proposed. Conclusions. The original algorithm of SH2 domains research with molecular docking method was developed. Using our algorithm, the active compounds for SH2 domains were found.

  14. Study of the validity of a combined potential model using the Hybrid Reverse Monte Carlo method in Fluoride glass system

    Directory of Open Access Journals (Sweden)

    M. Kotbi

    2013-03-01

    Full Text Available The choice of appropriate interaction models is among the major disadvantages of conventional methods such as Molecular Dynamics (MD and Monte Carlo (MC simulations. On the other hand, the so-called Reverse Monte Carlo (RMC method, based on experimental data, can be applied without any interatomic and/or intermolecular interactions. The RMC results are accompanied by artificial satellite peaks. To remedy this problem, we use an extension of the RMC algorithm, which introduces an energy penalty term into the acceptance criteria. This method is referred to as the Hybrid Reverse Monte Carlo (HRMC method. The idea of this paper is to test the validity of a combined potential model of coulomb and Lennard-Jones in a Fluoride glass system BaMnMF7 (M = Fe,V using HRMC method. The results show a good agreement between experimental and calculated characteristics, as well as a meaningful improvement in partial pair distribution functions (PDFs. We suggest that this model should be used in calculating the structural properties and in describing the average correlations between components of fluoride glass or a similar system. We also suggest that HRMC could be useful as a tool for testing the interaction potential models, as well as for conventional applications.

  15. Novel Method for Sizing Metallic Bottom Crack Depth Using Multi-frequency Alternating Current Potential Drop Technique

    Directory of Open Access Journals (Sweden)

    Li Yuting

    2015-10-01

    Full Text Available Potential drop techniques are of two types: the direct current potential drop (DCPD technique and alternating current potential drop (ACPD technique, and both of them are used in nondestructive testing. ACPD, as a kind of valid method in sizing metal cracks, has been applied to evaluate metal structures. However, our review of most available approaches revealed that some improvements can be done in measuring depth of metal bottom crack by means of ACPD, such as accuracy and sensitivity of shallow crack. This paper studied a novel method which utilized the slope of voltage ratio-frequency curve to solve bottom crack depth by using a simple mathematic equation based on finite element analysis. It is found that voltage ratio varies linearly with frequency in the range of 5-15 Hz; this range is slightly higher than the equivalent frequency and lower than semi-permeable frequency. Simulation and experiment show that the novel method can measure the bottom crack depth accurately.

  16. The ab initio model potential method. Second series transition metal elements

    International Nuclear Information System (INIS)

    Barandiaran, Z.; Seijo, L.; Huzinaga, S.

    1990-01-01

    The ab initio core method potential model (AIMP) has already been presented in its nonrelativistic version and applied to the main group and first series transition metal elements [J. Chem. Phys. 86, 2132 (1987); 91, 7011 (1989)]. In this paper we extend the AIMP method to include relativistic effects within the Cowan--Griffin approximation and we present relativistic Zn-like core model potentials and valence basis sets, as well as their nonrelativistic Zn-like core and Kr-like core counterparts. The pilot molecular calculations on YO, TcO, AgO, and AgH reveal that the 4p orbital is indeed a core orbital only at the end part of the series, whereas the 4s orbital can be safely frozen from Y to Cd. The all-electron and model potential results agree in 0.01--0.02 A in R e and 25--50 cm -1 in bar ν e if the same type of valence part of the basis set is used. The comparison of the relativistic results on AgH with those of the all-electron Dirac--Fock calculations by Lee and McLean is satisfactory: the absolute value of R e is reproduced within the 0.01 A margin and the relativistic contraction of 0.077 A is also very well reproduced (0.075 A). Finally, the relative magnitude of the effects of the core orbital change, mass--velocity potential, and Darwin potential on the net relativistic effects are analyzed in the four molecules studied

  17. Variance of a potential of mean force obtained using the weighted histogram analysis method.

    Science.gov (United States)

    Cukier, Robert I

    2013-11-27

    A potential of mean force (PMF) that provides the free energy of a thermally driven system along some chosen reaction coordinate (RC) is a useful descriptor of systems characterized by complex, high dimensional potential energy surfaces. Umbrella sampling window simulations use potential energy restraints to provide more uniform sampling along a RC so that potential energy barriers that would otherwise make equilibrium sampling computationally difficult can be overcome. Combining the results from the different biased window trajectories can be accomplished using the Weighted Histogram Analysis Method (WHAM). Here, we provide an analysis of the variance of a PMF along the reaction coordinate. We assume that the potential restraints used for each window lead to Gaussian distributions for the window reaction coordinate densities and that the data sampling in each window is from an equilibrium ensemble sampled so that successive points are statistically independent. Also, we assume that neighbor window densities overlap, as required in WHAM, and that further-than-neighbor window density overlap is negligible. Then, an analytic expression for the variance of the PMF along the reaction coordinate at a desired level of spatial resolution can be generated. The variance separates into a sum over all windows with two kinds of contributions: One from the variance of the biased window density normalized by the total biased window density and the other from the variance of the local (for each window's coordinate range) PMF. Based on the desired spatial resolution of the PMF, the former variance can be minimized relative to that from the latter. The method is applied to a model system that has features of a complex energy landscape evocative of a protein with two conformational states separated by a free energy barrier along a collective reaction coordinate. The variance can be constructed from data that is already available from the WHAM PMF construction.

  18. First-principle optimal local pseudopotentials construction via optimized effective potential method

    International Nuclear Information System (INIS)

    Mi, Wenhui; Zhang, Shoutao; Wang, Yanchao; Ma, Yanming; Miao, Maosheng

    2016-01-01

    The local pseudopotential (LPP) is an important component of orbital-free density functional theory, a promising large-scale simulation method that can maintain information on a material’s electron state. The LPP is usually extracted from solid-state density functional theory calculations, thereby it is difficult to assess its transferability to cases involving very different chemical environments. Here, we reveal a fundamental relation between the first-principles norm-conserving pseudopotential (NCPP) and the LPP. On the basis of this relationship, we demonstrate that the LPP can be constructed optimally from the NCPP for a large number of elements using the optimized effective potential method. Specially, our method provides a unified scheme for constructing and assessing the LPP within the framework of first-principles pseudopotentials. Our practice reveals that the existence of a valid LPP with high transferability may strongly depend on the element.

  19. Potentials and limits of modern tomographic methods (CT, MR, PET) in molecular imaging

    International Nuclear Information System (INIS)

    Hentschel, M.; Paul, D.; Moser, E.; Brink, I.

    2007-01-01

    The present survey gives an introduction into the basics of computed tomography, magnetic resonance tomography and positron emission tomography. The current potentials of these methods in relation to their temporal, spatial and contrast resolutions as well as their sensitivities within clinical routine and experimental studies (in vitro, ex vivo) will be presented. Computed tomography constitutes the anatomical reference method with well defined contrast, high spatial resolution but low sensitivity (10 -2 mol/l) for functional and molecular imaging. Magnetic resonance tomography represents the anatomical method for research with variable tissue contrast, physiological image information, highest spatial resolution but moderate sensitivity (10 -3 -10 -5 mol/l) for functional and molecular imaging. Positron emission tomography offers good suitability for molecular imaging due to highest sensitivity (10 -11 -10 -12 mol/l). However, the spatial resolution of positron emission tomography is low. (orig.)

  20. Comparing the Efficacy of Excitatory Transcranial Stimulation Methods Measuring Motor Evoked Potentials

    Directory of Open Access Journals (Sweden)

    Vera Moliadze

    2014-01-01

    Full Text Available The common aim of transcranial stimulation methods is the induction or alterations of cortical excitability in a controlled way. Significant effects of each individual stimulation method have been published; however, conclusive direct comparisons of many of these methods are rare. The aim of the present study was to compare the efficacy of three widely applied stimulation methods inducing excitability enhancement in the motor cortex: 1 mA anodal transcranial direct current stimulation (atDCS, intermittent theta burst stimulation (iTBS, and 1 mA transcranial random noise stimulation (tRNS within one subject group. The effect of each stimulation condition was quantified by evaluating motor-evoked-potential amplitudes (MEPs in a fixed time sequence after stimulation. The analyses confirmed a significant enhancement of the M1 excitability caused by all three types of active stimulations compared to sham stimulation. There was no significant difference between the types of active stimulations, although the time course of the excitatory effects slightly differed. Among the stimulation methods, tRNS resulted in the strongest and atDCS significantly longest MEP increase compared to sham. Different time courses of the applied stimulation methods suggest different underlying mechanisms of action. Better understanding may be useful for better targeting of different transcranial stimulation techniques.

  1. According to the Method of Gulez Evaluation of the Recreational Potential of Kafkasör Urban Forest

    Directory of Open Access Journals (Sweden)

    Hilal Yılmaz

    2009-04-01

    Full Text Available Urban people not only attempt to satisfy their hunger for nature by performing some recreational activities in natural areas in their proximities but also they challenge to regain disappeared natural areas in and around their cities in order to make residential areas more liveable. When considered the conditions today, urban trees and forests have turned out to be obligatory facilities for urban people since they provide not only recreational services but also contributions to city aesthetics, public health (with clean air and oxygen supply, human psychology, city and national economy and urban ecology. In this study, it was aimed to determine the existent recreational potentials of Kafkasör urban forest in Artvin city by evaluating the recreational conditions of urban forests. For this aim, recreational value of Artvin Urban Forest tried to be calculated according to Gülez’s method in order to determine existent potentials of recreational areas. As the result of the study, it was found that recreational potential rate of the area was 66.9 %, which shows the area has high recreational potential. The most important factor affecting this high potential was found to be the landscape characteristics the area has and recreational facilities the area provides.

  2. A method for physically based model analysis of conjunctive use in response to potential climate changes

    Science.gov (United States)

    Hanson, R.T.; Flint, L.E.; Flint, A.L.; Dettinger, M.D.; Faunt, C.C.; Cayan, D.; Schmid, W.

    2012-01-01

    Potential climate change effects on aspects of conjunctive management of water resources can be evaluated by linking climate models with fully integrated groundwater-surface water models. The objective of this study is to develop a modeling system that links global climate models with regional hydrologic models, using the California Central Valley as a case study. The new method is a supply and demand modeling framework that can be used to simulate and analyze potential climate change and conjunctive use. Supply-constrained and demand-driven linkages in the water system in the Central Valley are represented with the linked climate models, precipitation-runoff models, agricultural and native vegetation water use, and hydrologic flow models to demonstrate the feasibility of this method. Simulated precipitation and temperature were used from the GFDL-A2 climate change scenario through the 21st century to drive a regional water balance mountain hydrologic watershed model (MHWM) for the surrounding watersheds in combination with a regional integrated hydrologic model of the Central Valley (CVHM). Application of this method demonstrates the potential transition from predominantly surface water to groundwater supply for agriculture with secondary effects that may limit this transition of conjunctive use. The particular scenario considered includes intermittent climatic droughts in the first half of the 21st century followed by severe persistent droughts in the second half of the 21st century. These climatic droughts do not yield a valley-wide operational drought but do cause reduced surface water deliveries and increased groundwater abstractions that may cause additional land subsidence, reduced water for riparian habitat, or changes in flows at the Sacramento-San Joaquin River Delta. The method developed here can be used to explore conjunctive use adaptation options and hydrologic risk assessments in regional hydrologic systems throughout the world.

  3. A combined vector potential-scalar potential method for FE computation of 3D magnetic fields in electrical devices with iron cores

    Science.gov (United States)

    Wang, R.; Demerdash, N. A.

    1991-01-01

    A method of combined use of magnetic vector potential based finite-element (FE) formulations and magnetic scalar potential (MSP) based formulations for computation of three-dimensional magnetostatic fields is introduced. In this method, the curl-component of the magnetic field intensity is computed by a reduced magnetic vector potential. This field intensity forms the basic of a forcing function for a global magnetic scalar potential solution over the entire volume of the region. This method allows one to include iron portions sandwiched in between conductors within partitioned current-carrying subregions. The method is most suited for large-scale global-type 3-D magnetostatic field computations in electrical devices, and in particular rotating electric machinery.

  4. The versatile biopolymer chitosan: potential sources, evaluation of extraction methods and applications.

    Science.gov (United States)

    Kaur, Surinder; Dhillon, Gurpreet Singh

    2014-05-01

    Among the biopolymers, chitin and its derivative chitosan (CTS) have been receiving increasing attention. Both are composed of randomly distributed β-(1-4)-linked d-glucosamine and N-acetyl glucosamine units. On commercial scale, CTS is mainly obtained from the crustacean shells. The chemical methods employed for extraction of CTS from crustacean shells are laden with many disadvantages. Waste fungal biomass represents a potential biological source of CTS, in fact with superior physico-chemical properties, such as high degree of deacetylation, low molecular weight, devoid of protein contamination and high bioactivity. Researchers around the globe are attempting to commercialize CTS production and extraction from fungal sources. Fungi are promising and environmentally benign source of CTS and they have the potential to completely replace crustacean-derived CTS. Waste fungal biomass resulting from various pharmaceutical and biotechnological industries is grown on inexpensive agro-industrial wastes and its by-products are a rich and inexpensive source of CTS. CTS is emerging as an important natural polymer having broad range of applications in different fields. In this context, the present review discusses the potential sources of CTS and their advantages and disadvantages. This review also deals with potential applications of CTS in different fields. Finally, the various attributes of CTS sought in different applications are discussed.

  5. Method and apparatus for determining the spontaneous earth potential log from downhole gradient measurements

    International Nuclear Information System (INIS)

    Maciejewski, W. J.

    1985-01-01

    A method and apparatus for measuring the differential or gradient of an earth variable within a well bore (e.g., the spontaneous earth potential) and producing improved logs of this gradient or differential and its integral variable essentially free of any accumulated instrument and base line drift or error. The differential spontaneous potential of an earth formation traversed by a well bore is measured at repeated multiple depths by moving a pair of closely spaced electrodes through the well bore wherein each electrode is electrically insulated externally from the other and from a third downhole local ground (such as the well tool cable) to which each is internally resistively referenced. The measured electrical potential across the closely spaced electrodes is amplified and digitized before being transmitted to the earth's surface, whereupon an averaged value of such differential measurements within a traveling data window of predetermined length and adjacent to each successive measurement is used to adjust for base line drift, noise and instrument induced error. The resulting compensated differential logs are integrated, resulting in spontaneous potential logs of improved character

  6. A universal meteorological method to identify potential risk of wind erosion on heavy-textured soils

    Directory of Open Access Journals (Sweden)

    Středová Hana

    2015-06-01

    Full Text Available The climate of Central Europe, mainly winter seasons with no snow cover at lower altitudes and a spring drought as well, might cause erosion events on heavy-textured soils. The aim of this paper is to define a universal method to identify the potential risk of wind erosion on heavy-textured soils. The categorization of potential wind erosion risk due to meteorological conditions is based on: (i an evaluation of the number of freeze-thaw episodes forming bare soil surfaces during the cold period of year; and (ii, an evaluation of the number of days with wet soil surfaces during the cold period of year. In the period 2001–2012 (from November to March, episodes with temperature changes from positive to negative and vice versa (thaw-freeze and freeze-thaw cycles and the effects of wet soil surfaces in connection with aggregate disintegration, are identified. The data are spatially interpolated by GIS tools for areas in the Czech Republic with heavy-textured soils. Blending critical categories is used to locate potential risks. The level of risk is divided into six classes. Those areas identified as potentially most vulnerable are the same localities where the highest number of erosive episodes on heavy-textured soils was documented.

  7. Standard test method for measurement of oxidation-reduction potential (ORP) of soil

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2009-01-01

    1.1 This test method covers a procedure and related test equipment for measuring oxidation-reduction potential (ORP) of soil samples removed from the ground. 1.2 The procedure in Section 9 is appropriate for field and laboratory measurements. 1.3 Accurate measurement of oxidation-reduction potential aids in the analysis of soil corrosivity and its impact on buried metallic structure corrosion rates. 1.4 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  8. A novel method for extraction of neural response from single channel cochlear implant auditory evoked potentials.

    Science.gov (United States)

    Sinkiewicz, Daniel; Friesen, Lendra; Ghoraani, Behnaz

    2017-02-01

    Cortical auditory evoked potentials (CAEP) are used to evaluate cochlear implant (CI) patient auditory pathways, but the CI device produces an electrical artifact, which obscures the relevant information in the neural response. Currently there are multiple methods, which attempt to recover the neural response from the contaminated CAEP, but there is no gold standard, which can quantitatively confirm the effectiveness of these methods. To address this crucial shortcoming, we develop a wavelet-based method to quantify the amount of artifact energy in the neural response. In addition, a novel technique for extracting the neural response from single channel CAEPs is proposed. The new method uses matching pursuit (MP) based feature extraction to represent the contaminated CAEP in a feature space, and support vector machines (SVM) to classify the components as normal hearing (NH) or artifact. The NH components are combined to recover the neural response without artifact energy, as verified using the evaluation tool. Although it needs some further evaluation, this approach is a promising method of electrical artifact removal from CAEPs. Copyright © 2016 IPEM. Published by Elsevier Ltd. All rights reserved.

  9. Relativistic symmetries in the Rosen—Morse potential and tensor interaction using the Nikiforov—Uvarov method

    International Nuclear Information System (INIS)

    Ikhdair Sameer M; Hamzavi Majid

    2013-01-01

    Approximate analytical bound-state solutions of the Dirac particle in the fields of attractive and repulsive Rosen—Morse (RM) potentials including the Coulomb-like tensor (CLT) potential are obtained for arbitrary spin-orbit quantum number κ. The Pekeris approximation is used to deal with the spin-orbit coupling terms κ (κ± 1)r −2 . In the presence of exact spin and pseudospin (p-spin) symmetries, the energy eigenvalues and the corresponding normalized two-component wave functions are found by using the parametric generalization of the Nikiforov—Uvarov (NU) method. The numerical results show that the CLT interaction removes degeneracies between the spin and p-spin state doublets. (general)

  10. A novel method for beef potentiator preparation and identification of its characteristic aroma compounds.

    Science.gov (United States)

    Gao, Xianli; Yan, Shuang; Yang, Bao; Lu, Jian; Jin, Zhao

    2014-06-01

    Beef potentiator (BP) is the most popular savoury flavour and regarded as the soul of the modern food industry. In this work, BP was prepared by a novel method with Aspergillus oryzae and Aspergillus niger (BPSF). Three other BPs prepared using commercial enzymes (Protamex, Flavourzyme and papain; BPCEs) were used as controls to investigate its aroma characteristics and related compounds. Sensory evaluation showed that BPSF possessed more favourable and distinctive sauce-like, meat-like, roast and alcoholic attributes when compared with BPCEs. Significantly higher contents (peak areas) and proportions of pyrazines, pyrroles, sulfurous compounds and alcohols in BPSF were responsible for its sensory characteristics, and most of these aroma compounds were derived from microbial metabolism during beef koji preparation and the Maillard reaction. BP prepared by synergistic fermentation with A. oryzae and A. niger is a potential alternative for BP preparation. © 2013 Society of Chemical Industry.

  11. Talking with TV shows

    DEFF Research Database (Denmark)

    Sandvik, Kjetil; Laursen, Ditte

    2014-01-01

    User interaction with radio and television programmes is not a new thing. However, with new cross-media production concepts such as X Factor and Voice, this is changing dramatically. The second-screen logic of these productions encourages viewers, along with TV’s traditional one-way communication...... mode, to communicate on interactive (dialogue-enabling) devices such as laptops, smartphones and tablets. Using the TV show Voice as our example, this article shows how the technological and situational set-up of the production invites viewers to engage in new ways of interaction and communication...

  12. Systematic method for resource rating with two applications to potential wilderness areas

    International Nuclear Information System (INIS)

    Voelker, A.H.; Wedow, H.; Oakes, E.; Scheffler, P.K.

    1979-09-01

    A versatile method was developed to rate the energy- and mineral-resource potentials of areas in which land-management and resource-development decisions must be reached with a minimum expenditure of money and time. The method surveys published and personal information on resources in the region being assessed, selects the most appropriate information, synthesizes the information into map overlays and tract descriptions, rates the potential of tracts for particular resources, rates the overall importance of each tract for resource development, and documents the ratings and their significance. Basic criteria considered by the assessment team include the favorability and certainty ratings, the overall availability of each rated resource within this country, the size of a given tract, economic factors, and the number of resources in a tract. The method was applied to two separate but roughly similar geologic regions, the Idaho-Wyoming-Utah thrust belt and the central Appalachians. Undeveloped tracts of national forestland in these regions that are being considered for possible designation under the Roadless Area Review and Evaluation (RARE II) planning process were rated for their resource value. Results support earlier indications that the 63 tracts comprising the western thrust belt possess a high potential for future resource development. Nearly one-half of these tracts were rated either 3 or 4. However, the wide spread of the importance ratings between 1 and 4 suggests that some tracts or portions of tracts can be added to the National Wilderness System without compromising resource development. The 72 eastern thrust belt tracts were given lower ratings, which indicates the reduced significance of the few remaining roadless areas in this region in satisfying the nation's near-term resource needs

  13. Talk Show Science.

    Science.gov (United States)

    Moore, Mitzi Ruth

    1992-01-01

    Proposes having students perform skits in which they play the roles of the science concepts they are trying to understand. Provides the dialog for a skit in which hot and cold gas molecules are interviewed on a talk show to study how these properties affect wind, rain, and other weather phenomena. (MDH)

  14. Obesity in show cats.

    Science.gov (United States)

    Corbee, R J

    2014-12-01

    Obesity is an important disease with a high prevalence in cats. Because obesity is related to several other diseases, it is important to identify the population at risk. Several risk factors for obesity have been described in the literature. A higher incidence of obesity in certain cat breeds has been suggested. The aim of this study was to determine whether obesity occurs more often in certain breeds. The second aim was to relate the increased prevalence of obesity in certain breeds to the official standards of that breed. To this end, 268 cats of 22 different breeds investigated by determining their body condition score (BCS) on a nine-point scale by inspection and palpation, at two different cat shows. Overall, 45.5% of the show cats had a BCS > 5, and 4.5% of the show cats had a BCS > 7. There were significant differences between breeds, which could be related to the breed standards. Most overweight and obese cats were in the neutered group. It warrants firm discussions with breeders and cat show judges to come to different interpretations of the standards in order to prevent overweight conditions in certain breeds from being the standard of beauty. Neutering predisposes for obesity and requires early nutritional intervention to prevent obese conditions. Journal of Animal Physiology and Animal Nutrition © 2014 Blackwell Verlag GmbH.

  15. Honored Teacher Shows Commitment.

    Science.gov (United States)

    Ratte, Kathy

    1987-01-01

    Part of the acceptance speech of the 1985 National Council for the Social Studies Teacher of the Year, this article describes the censorship experience of this honored social studies teacher. The incident involved the showing of a videotape version of the feature film entitled "The Seduction of Joe Tynan." (JDH)

  16. Atomistic simulations of materials: Methods for accurate potentials and realistic time scales

    Science.gov (United States)

    Tiwary, Pratyush

    This thesis deals with achieving more realistic atomistic simulations of materials, by developing accurate and robust force-fields, and algorithms for practical time scales. I develop a formalism for generating interatomic potentials for simulating atomistic phenomena occurring at energy scales ranging from lattice vibrations to crystal defects to high-energy collisions. This is done by fitting against an extensive database of ab initio results, as well as to experimental measurements for mixed oxide nuclear fuels. The applicability of these interactions to a variety of mixed environments beyond the fitting domain is also assessed. The employed formalism makes these potentials applicable across all interatomic distances without the need for any ambiguous splining to the well-established short-range Ziegler-Biersack-Littmark universal pair potential. We expect these to be reliable potentials for carrying out damage simulations (and molecular dynamics simulations in general) in nuclear fuels of varying compositions for all relevant atomic collision energies. A hybrid stochastic and deterministic algorithm is proposed that while maintaining fully atomistic resolution, allows one to achieve milliseconds and longer time scales for several thousands of atoms. The method exploits the rare event nature of the dynamics like other such methods, but goes beyond them by (i) not having to pick a scheme for biasing the energy landscape, (ii) providing control on the accuracy of the boosted time scale, (iii) not assuming any harmonic transition state theory (HTST), and (iv) not having to identify collective coordinates or interesting degrees of freedom. The method is validated by calculating diffusion constants for vacancy-mediated diffusion in iron metal at low temperatures, and comparing against brute-force high temperature molecular dynamics. We also calculate diffusion constants for vacancy diffusion in tantalum metal, where we compare against low-temperature HTST as well

  17. Electrochemical noise measurements techniques and the reversing dc potential drop method applied to stress corrosion essays

    International Nuclear Information System (INIS)

    Aly, Omar Fernandes; Andrade, Arnaldo Paes de; MattarNeto, Miguel; Aoki, Idalina Vieira

    2002-01-01

    This paper aims to collect information and to discuss the electrochemical noise measurements and the reversing dc potential drop method, applied to stress corrosion essays that can be used to evaluate the nucleation and the increase of stress corrosion cracking in Alloy 600 and/or Alloy 182 specimens from Angra I Nuclear Power Plant. Therefore we will pretend to establish a standard procedure to essays to be realized on the new autoclave equipment on the Laboratorio de Eletroquimica e Corrosao do Departamento de Engenharia Quimica da Escola Politecnica da Universidade de Sao Paulo - Electrochemical and Corrosion Laboratory of the Chemical Engineering Department of Polytechnical School of Sao Paulo University, Brazil. (author)

  18. Cost and effectiveness comparison of two methods for screening potential blood donors for anaemia in Vietnam.

    Science.gov (United States)

    Tyrrell, A; Worrall, E; Que, T N; Bates, I

    2011-06-01

    To compare the cost and effectiveness of Copper Sulphate (CS) and HemoCue (HC) methods for screening blood donors for anaemia. Robust information from developing countries about cost and effectiveness of anaemia screening methods for blood donors is scarce. In such countries there are widespread shortages of blood, so the most cost-effective method should maximise blood supply without compromising donor safety. Economic data (e.g. staff time, equipment and buildings) were collected from direct observation of procedures and purchase data from Hanoi's Central Blood Bank administrative department. A framework for comparing the cost and effectiveness of anaemia screening methods was developed and a cost per effective (i.e. usable and accurate) test was generated for each method. Samples from 100 potential donors from the Hanoi Central Blood Bank (static) and 198 from two mobile units were tested. The mean probability of an ineffective anaemia test was 0·1 (0·05-0·2). The average cost of an HC test was $0·75 (static $0·61 and mobile $0·89) and a CS test was $0·31 (static $0·17 and mobile $0·45). The difference between static and mobile units was predominantly due to transport costs; the difference between the two methods was predominantly due to the HC microcuvettes. In this setting the CS yields greater value for money than the HC method for screening blood donors. The relative cost and effectiveness of CS and HC may be different in places with higher staff turnover, lower test accuracy, higher anaemia prevalence or lower workload than in Vietnam. © 2010 Liverpool School of Tropical Medicine. Transfusion Medicine © 2010 British Blood Transfusion Society.

  19. Comparison of the common spatial interpolation methods used to analyze potentially toxic elements surrounding mining regions.

    Science.gov (United States)

    Ding, Qian; Wang, Yong; Zhuang, Dafang

    2018-04-15

    The appropriate spatial interpolation methods must be selected to analyze the spatial distributions of Potentially Toxic Elements (PTEs), which is a precondition for evaluating PTE pollution. The accuracy and effect of different spatial interpolation methods, which include inverse distance weighting interpolation (IDW) (power = 1, 2, 3), radial basis function interpolation (RBF) (basis function: thin-plate spline (TPS), spline with tension (ST), completely regularized spline (CRS), multiquadric (MQ) and inverse multiquadric (IMQ)) and ordinary kriging interpolation (OK) (semivariogram model: spherical, exponential, gaussian and linear), were compared using 166 unevenly distributed soil PTE samples (As, Pb, Cu and Zn) in the Suxian District, Chenzhou City, Hunan Province as the study subject. The reasons for the accuracy differences of the interpolation methods and the uncertainties of the interpolation results are discussed, then several suggestions for improving the interpolation accuracy are proposed, and the direction of pollution control is determined. The results of this study are as follows: (i) RBF-ST and OK (exponential) are the optimal interpolation methods for As and Cu, and the optimal interpolation method for Pb and Zn is RBF-IMQ. (ii) The interpolation uncertainty is positively correlated with the PTE concentration, and higher uncertainties are primarily distributed around mines, which is related to the strong spatial variability of PTE concentrations caused by human interference. (iii) The interpolation accuracy can be improved by increasing the sample size around the mines, introducing auxiliary variables in the case of incomplete sampling and adopting the partition prediction method. (iv) It is necessary to strengthen the prevention and control of As and Pb pollution, particularly in the central and northern areas. The results of this study can provide an effective reference for the optimization of interpolation methods and parameters for

  20. A method for determination of X-ray elastic constants of materials showing non-linear sin2ψ diagrams and its application to Zn-Ni-alloy electroplate

    International Nuclear Information System (INIS)

    Sasaki, Toshihiko; Kuramoto, Makoto; Yoshioka, Yasuo.

    1990-01-01

    This paper describes the method and the experiment for the determination of the x-ray elastic constants of Zn-Ni-alloy electroplate. For this material, the sin 2 ψ method is not adequate to use because this material shows severely curved sin 2 ψ diagrams. Therefore, a new method developed by the authors was explained first. This new method is effective for materials showing nonlinear sin 2 ψ diagrams. Secondly, the experiment was made on the application of this method to the Zn-Ni-alloy electroplate. And it was found out that the experimental data agreed well to the theory of this method. As a result, the following values were obtained as the x-ray elastic constants of the sample measured: (1+ν)/E=8.44 TPa -1 ν/E=2.02 TPa -1 (author)

  1. Application of self-potential method in uranium exploration - a case study from Arbail, Karnataka, India

    International Nuclear Information System (INIS)

    Anantharaman, K.B.; Narasimha Rao, B.; Sethuram, S.; Rao, K.K.

    1986-01-01

    The application of non-radiometric geophysical methods like magnetic, electrical resistivity, induced polarisation, electromagnetic and seismic for uranium exploration has been discussed by many workers. In thispaper it has been demonstrated that the self-potential technique which is simple, fast and cheap can also be effectively and meaningfully employed. For this purpose, a case study from Arbail (Lat 14 0 , 50' 40'', Long 74 0 38' 25''), India where uranium mineralisation is known to occur in association with sulphides, is presented. The method of downward continuation is used to estimate the depth to the top of the target and the results thus obtained are correlated with the data obtained from subsequent borehole drilling. (author)

  2. DIFFERENTIAL DIAGNOSTICS MODEL RESEARCH BY MEANS OF THE POTENTIAL FUNCTIONS METHOD FOR NEUROLOGY DISEASES CLASSIFICATION

    Directory of Open Access Journals (Sweden)

    V. Z. Stetsyuk

    2016-10-01

    Full Text Available Informatization in medicine offers a lot of opportunities to enhance quality of medical support, accuracy of diagnosis and provides the use of accumulated experience. Modern program systems are utilized now as additional tools to get appropriate advice. This article offers the way to provide help for neurology department doctor of NCSH «OKHMATDYT» during diagnosis determining. It was decided to design the program system for this purpose based on differential diagnostic model. The key problems in differential diagnosis are symptoms similarity between each other in one disease group and the absence of key symptom. Therefore the differential diagnostic model is needed. It is constructed using the potential function method in characteristics space. This characteristics space is formed by 100-200 points - patients with their symptoms. The main feature of this method here is that the decision function is building during recognition step united with learning that became possible with the help of modern powerful computers.

  3. Complex absorbing potentials within EOM-CC family of methods: Theory, implementation, and benchmarks

    Energy Technology Data Exchange (ETDEWEB)

    Zuev, Dmitry; Jagau, Thomas-C.; Krylov, Anna I. [Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482 (United States); Bravaya, Ksenia B. [Department of Chemistry, Boston University, Boston, Massachusetts 02215-2521 (United States); Epifanovsky, Evgeny [Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482 (United States); Department of Chemistry, University of California, Berkeley, California 94720 (United States); Q-Chem, Inc., 6601 Owens Drive, Suite 105 Pleasanton, California 94588 (United States); Shao, Yihan [Q-Chem, Inc., 6601 Owens Drive, Suite 105 Pleasanton, California 94588 (United States); Sundstrom, Eric; Head-Gordon, Martin [Department of Chemistry, University of California, Berkeley, California 94720 (United States)

    2014-07-14

    A production-level implementation of equation-of-motion coupled-cluster singles and doubles (EOM-CCSD) for electron attachment and excitation energies augmented by a complex absorbing potential (CAP) is presented. The new method enables the treatment of metastable states within the EOM-CC formalism in a similar manner as bound states. The numeric performance of the method and the sensitivity of resonance positions and lifetimes to the CAP parameters and the choice of one-electron basis set are investigated. A protocol for studying molecular shape resonances based on the use of standard basis sets and a universal criterion for choosing the CAP parameters are presented. Our results for a variety of π{sup *} shape resonances of small to medium-size molecules demonstrate that CAP-augmented EOM-CCSD is competitive relative to other theoretical approaches for the treatment of resonances and is often able to reproduce experimental results.

  4. The energy show

    International Nuclear Information System (INIS)

    1988-01-01

    The Energy Show is a new look at the problems of world energy, where our supplies come from, now and in the future. The programme looks at how we need energy to maintain our standards of living. Energy supply is shown as the complicated set of problems it is - that Fossil Fuels are both raw materials and energy sources, that some 'alternatives' so readily suggested as practical options are in reality a long way from being effective. (author)

  5. Optimizing event-related potential based brain-computer interfaces: a systematic evaluation of dynamic stopping methods

    Science.gov (United States)

    Schreuder, Martijn; Höhne, Johannes; Blankertz, Benjamin; Haufe, Stefan; Dickhaus, Thorsten; Tangermann, Michael

    2013-06-01

    Objective. In brain-computer interface (BCI) research, systems based on event-related potentials (ERP) are considered particularly successful and robust. This stems in part from the repeated stimulation which counteracts the low signal-to-noise ratio in electroencephalograms. Repeated stimulation leads to an optimization problem, as more repetitions also cost more time. The optimal number of repetitions thus represents a data-dependent trade-off between the stimulation time and the obtained accuracy. Several methods for dealing with this have been proposed as ‘early stopping’, ‘dynamic stopping’ or ‘adaptive stimulation’. Despite their high potential for BCI systems at the patient's bedside, those methods are typically ignored in current BCI literature. The goal of the current study is to assess the benefit of these methods. Approach. This study assesses for the first time the existing methods on a common benchmark of both artificially generated data and real BCI data of 83 BCI sessions, allowing for a direct comparison between these methods in the context of text entry. Main results. The results clearly show the beneficial effect on the online performance of a BCI system, if the trade-off between the number of stimulus repetitions and accuracy is optimized. All assessed methods work very well for data of good subjects, and worse for data of low-performing subjects. Most methods, however, are robust in the sense that they do not reduce the performance below the baseline of a simple no stopping strategy. Significance. Since all methods can be realized as a module between the BCI and an application, minimal changes are needed to include these methods into existing BCI software architectures. Furthermore, the hyperparameters of most methods depend to a large extend on only a single variable—the discriminability of the training data. For the convenience of BCI practitioners, the present study proposes linear regression coefficients for directly estimating

  6. A Comparison of Streaming and Microelectrophoresis Methods for Obtaining the zeta Potential of Granular Porous Media Surfaces.

    Science.gov (United States)

    Johnson

    1999-01-01

    The electrokinetic behavior of granular quartz sand in aqueous solution is investigated by both microelectrophoresis and streaming potential methods. zeta potentials of surfaces composed of granular quartz obtained via streaming potential methods are compared to electrophoretic mobility zeta potential values of colloid-sized quartz fragments. The zeta values generated by these alternate methods are in close agreement over a wide pH range and electrolyte concentrations spanning several orders of magnitude. Streaming measurements performed on chemically heterogeneous mixtures of physically homogeneous sand are shown to obey a simple mixing model based on the surface area-weighted average of the streaming potentials associated with the individual end members. These experimental results support the applicability of the streaming potential method as a means of determining the zeta potential of granular porous media surfaces. Copyright 1999 Academic Press.

  7. [Investigation of potential toxic factors for fleece-flower root: from perspective of processing methods evolution].

    Science.gov (United States)

    Cui, He-Rong; Bai, Zhao-Fang; Song, Hai-Bo; Jia, Tian-Zhu; Wang, Jia-Bo; Xiao, Xiao-He

    2016-01-01

    In recent years, the rapid growth of reports on fleece-flower root-caused liver damages has drawn wide attention of both at home and abroad, however, there were rare literature on toxicology of fleece-flower root in ancient Chinese medicine. But why there are so many reports on toxicology of fleece-flower root now compared with the ancient literature? As a typical tonic medicine, the clinical utility of fleece-flower root was largely limited by its standardization and reliability of processing methods in ancient Chinese medicine. The ancient processing methods of fleece-flower root emphasized nine times of steaming and nine times of drying, while the modern processes have been simplified into one time of steaming. Whether the differences between ancient and modern processing methods are the potential cause of the increased events of fleece-flower root-caused liver damages. We will make deep analysis and provide new clues and perspectives for the research on its toxicity. This article, therefore, would discuss the affecting factors and key problems in toxicity attenuation of fleece-flower root on the basis of sorting out the processing methods of fleece-flower root in ancient medical books and modern standards, in order to provide the reference for establishing specification for toxicity attenuation of fleece-flower root. Copyright© by the Chinese Pharmaceutical Association.

  8. An Improved Unmixing-Based Fusion Method: Potential Application to Remote Monitoring of Inland Waters

    Directory of Open Access Journals (Sweden)

    Yulong Guo

    2015-02-01

    Full Text Available Although remote sensing technology has been widely used to monitor inland water bodies; the lack of suitable data with high spatial and spectral resolution has severely obstructed its practical development. The objective of this study is to improve the unmixing-based fusion (UBF method to produce fused images that maintain both spectral and spatial information from the original images. Images from Environmental Satellite 1 (HJ1 and Medium Resolution Imaging Spectrometer (MERIS were used in this study to validate the method. An improved UBF (IUBF algorithm is established by selecting a proper HJ1-CCD image band for each MERIS band and thereafter applying an unsupervised classification method in each sliding window. Viewing in the visual sense—the radiance and the spectrum—the results show that the improved method effectively yields images with the spatial resolution of the HJ1-CCD image and the spectrum resolution of the MERIS image. When validated using two datasets; the ERGAS index (Relative Dimensionless Global Error indicates that IUBF is more robust than UBF. Finally, the fused data were applied to evaluate the chlorophyll a concentrations (Cchla in Taihu Lake. The result shows that the Cchla map obtained by IUBF fusion captures more detailed information than that of MERIS.

  9. Developmental instability in German Iris flower as a potential biomonitoring method

    Directory of Open Access Journals (Sweden)

    Barišić-Klisarić Nataša

    2016-01-01

    Full Text Available In light of the increasing need for appropriate, cost-effective detection methods of anthropogenic pollution, we evaluated the biomonitoring potential of flower developmental instability (DI on a widely planted decorative species, Iris germanica, under in situ conditions. DI was measured by fluctuating and radial asymmetries of parts of Iris germanica perianth (810 fall lengths and widths, from clones already growing in two distinct types of habitats with contrasting levels of anthropogenic pollution: in unpolluted (rural areas, Novi Banovci, Stari Banovci and Belegiš (flowers from 137 clones sampled, and in a polluted (urban Belgrade metropolitan area (flowers from 133 clones sampled. Our results revealed significantly higher flower radial asymmetry in the polluted habitats compared to unpolluted ones (for three out of four univariate indices, as well as both multivariate ones, but failed to detect a similar effect on fluctuating asymmetry indices. The results of our study therefore demonstrate the potential of DI (when estimated by flower radial asymmetry in Iris germanica as a cost-effective biomonitoring method for in situ pollution detection based on readily measurable flower parts and moderate sample sizes. [Projekat Ministarstva nauke Republike Srbije, br. 173025: Evolution in heterogeneous environments: mechanisms of adaptation, biomonitoring and conservation of biodiversity

  10. Resource potential methods using for efficiency of activities in the region increase

    Directory of Open Access Journals (Sweden)

    M. P. Vasiliev

    2016-01-01

    Full Text Available The article considers impact methods on the economic results, the effectiveness of the regional economic complex should be based on a high quality of the basic characteristics classification of the region state. Application composition techniques to ensure a comprehensive impact on the achievement of this goal should in synthesized form to union, adopt a target orientation of development of the region with the parameters objectively revealing his condition. Ensuring organizational, economic, financial and investment techniques to achieve the planned targets and requires specifying align resource potential of the region with the available capacity of the regional economic complex to promote economic growth, improve the efficiency of operations. The main characteristics of the potential resource opportunities in the region are the skill level of workers, the degree of depreciation of fixed assets and their renewability, increased innovation in the region, its branches and facilities, strengthening of competitive advantages, the annual average number of employees, the cost of fixed and current assets, financial stability. In the region the opportunity to potentially affect the ability of its structural components to achieve the financial and economic performance targets acts as efficiency ability to provide stable dynamics of regional production efficiency, enhance the level of benefits to achieve the planned efficiency used (consumed resource. Applying of certain methods or their entire structure, created to provide a comprehensive impact on the goal achievement, in the synthesized form of target orientation combines regional development with the parameters most objectively revealing his condition. Achieving the appropriate organizational, economic, financial, investment or other measures to achieve planned targets that are expressed by the level of efficiency of activity in the conditions of the most complete involvement and intensity of use in

  11. Determining the U-Value of Façades Using the Thermometric Method: Potentials and Limitations

    Directory of Open Access Journals (Sweden)

    David Bienvenido-Huertas

    2018-02-01

    Full Text Available The thermal transmittance of building envelopes determines to a large extent the energy demand of buildings. Thus, there is a keen interest in having methods which can precisely evaluate thermal transmittance. From a scientific point of view, this study analyses the viability of the application of the thermometric method (THM, one of the most used methods in Spain. For this purpose, the test method has been improved by determining the adequate test conditions, the selection and installation of equipment, data acquisition and post-processing, and the estimation of uncertainty. We analyse eight case studies in a Mediterranean climate (Csa to determine the potentials and limitations of the method. The results show that the values obtained through THM are valid under winter environmental conditions with relative uncertainties between 6% and 13%, while difficulties to perform the test in optimal conditions, and therefore to obtain valid results in warmer seasons, are detected. In this regard, the case studies which obtained a greater number of observations by performing the filtrate conditions were able to obtain representative results. Furthermore, there are significant differences depending on the kind of equipment and probes used during the experimental campaign. Finally, in warm climate regions a data filtrate can be considered for observations of a temperature difference higher than 5 °C, obtaining valid results for the case studies, although the rise in the thermal gradient can guarantee a greater stability of data.

  12. Prognostic potential of n-cadherin in oral squamous cell carcinoma via immunohistochemical methods

    International Nuclear Information System (INIS)

    Chandolia, B.; Arora, M.; Rajliwal, P.

    2017-01-01

    To assess the prognostic potential for N-cadherin in oral squamous cell carcinoma and oral epithelial dysplasia. Study Design: A cross-sectional study, analytical study. Place and Duration of Study: Maharishi Markandeshwar College of Dental Science Research (MMCDSR), Ambala, India, from 2011 to 2014. Methodology: Immunohistochemistry was used to observe the N-cadherin expression in 100 cases having epithelium with normal oral mucosa, oral epithelial dysplastic lesions and oral squamous cell carcinoma (OSCC). For statistical significance, SPSS 13.0 was used to calculate the data by Mann-Whitney and Kruskal-Wallis tests. Results: In OSCC, N-cadherin expression was more evident than in oral epithelial dysplasia followed by the normal oral epithelium that did not show any dysplastic changes (p=0.001). Conversely, N-cadherin expression was not significant among the histological grade of OSCC. Conclusion: N-cadherin can be used as a potential biomarker for early diagnosis of OSCC. However, the N-cadherin expression did not show any correlation with the histological grade of OSCC. (author)

  13. Prognostic Potential of N-Cadherin in Oral Squamous Cell Carcinoma via Immunohistochemical Methods.

    Science.gov (United States)

    Chandolia, Betina; Rajliwal, Jai Parkash; Bajpai, Manas; Arora, Manika

    2017-08-01

    To assess the prognostic potential for N-cadherin in oral squamous cell carcinoma and oral epithelial dysplasia. Across-sectional study, analytical study. Maharishi Markandeshwar College of Dental Science Research (MMCDSR), Ambala, India, from 2011 to 2014. Immunohistochemistry was used to observe the N-cadherin expression in 100 cases having epithelium with normal oral mucosa, oral epithelial dysplastic lesions and oral squamous cell carcinoma (OSCC). For statistical significance, SPSS 13.0 was used to calculate the data by Mann-Whitney and Kruskal-Wallis tests. In OSCC, N-cadherin expression was more evident than in oral epithelial dysplasia followed by the normal oral epithelium that did not show any dysplastic changes (p=0.001). Conversely, N-cadherin expression was not significant among the histological grade of OSCC. N-cadherin can be used as a potential biomarker for early diagnosis of OSCC. However, the N-cadherin expression did not show any correlation with the histological grade of OSCC.

  14. A yeast glycolipid biosurfactant, mannosylerythritol lipid, shows potential moisturizing activity toward cultured human skin cells: the recovery effect of MEL-A on the SDS-damaged human skin cells.

    Science.gov (United States)

    Morita, Tomotake; Kitagawa, Masaru; Suzuki, Michiko; Yamamoto, Shuhei; Sogabe, Atsushi; Yanagidani, Shusaku; Imura, Tomohiro; Fukuoka, Tokuma; Kitamoto, Dai

    2009-01-01

    Mannosylerythritol lipids (MELs) are produced in large amounts from renewable vegetable oils by Pseudozyma antarctica, and are the most promising biosurfactants known due to its versatile interfacial and biochemical actions. In order to broaden the application in cosmetics and pharmaceuticals, the skin care property of MEL-A, the major component of MELs, was investigated using a three-dimensional cultured human skin model. The skin cells were cultured and treated with sodium dodecyl sulfate (SDS) solution of 1 wt%, and the effects of different lipids on the SDS-damaged cells were then evaluated on the basis of the cell viability. The viability of the damaged cells was markedly recovered by the addition of MEL-A in a dose-dependent manner. Compared to the control, MEL-A solutions of 5 wt% and 10 wt% gave the recovery rate of 73% and 91%, respectively, while ceramide solution of 1 wt% gave the rate of over 100%. This revealed that MEL-A shows a ceramide-like moisturizing activity toward the skin cells. Considering the drawbacks of natural ceramides, namely limited amount and high production cost, the yeast biosurfactants should have a great potential as a novel moisturizer for treating the damaged skin.

  15. Knowledge and usage of methods of online promotion by students as potential entrepreneurs

    Directory of Open Access Journals (Sweden)

    Siemieniak Paulina

    2017-01-01

    Full Text Available According to popular belief, it has never been easier to raise funds to run and manage one’s own business. In an era of startups popping up like mushrooms, crowdfunding, business angels, venture capital and mobile Internet, investing in a business is a much easier undertaking than it was two decades ago. Furthermore, Augmented Reality available through mobile devices like smartphones or tablets, the Internet of Things, which makes the consumer feel like a science fiction character in their own home, or Virtual Reality shopping, a Matrix movie-like experience in a testing phase at the moment, provide increasingly more innovative ways to take one’s first steps in business, gather momentum, and win loyal customers. According to the results, running one’s own business is not a popular professional plan among young people, which is especially surprising given the fact that the majority of the respondents were students of specialisations that equipped them with knowledge facilitating entrepreneurial activities. Running one’s own business seemed to be an attractive career path for about 30% of the respondents. Although they realise the significance of the Internet in running their own business, they do not believe that this is always a necessary tool. The students declared knowledge of multiple methods of communication and promotion and often use social media channels, but rarely expressed the desire to use these measures. A particular way of using the Internet to foster entrepreneurship are methods of online promotion like Social Media Marketing or Search Engine Optimization. Those tools enable reaching potential customers and engaging in an active dialogue with them about their favourite brands, products and services. They also allow exchange of information with the entrepreneur and are currently one of the fundamental tools for creating a company’s success. The article presents the results of research on the knowledge of methods of online

  16. Semiquantitative evaluation of "9"9mTctrodat1 binding potential by two methods of SPECT image reconstruction

    International Nuclear Information System (INIS)

    Leite, Melissa Furlaneto Lellis; Reis, Marilia Alves dos; Oliveira, Cassio Miri; Castiglioni, Mario Luiz Vieira; Bressan, Rodrigo Affonseca

    2017-01-01

    TRODAT-1 is a radiopharmaceutical derived from tropane and linked to Technetium-99m (["9"9"mTc] TRODAT-1) has been used in studies of dopamine transporter (DAT) in central nervous system. Associated with the SPECT technique of acquisition, is able to detect changes in neurological disorders like Parkinson´s disease, evaluating the binding potential (BP) of DAT. The aim of this study was to evaluate the influence of the image reconstruction methods, Filtered Back Projection (FBP) and iterative reconstruction (OSEM), in BP values at the striatal region in 30 healthy volunteers. Images were analyzed by visual inspection and semi-quantitative analysis. Regions of interest (ROI) were made over striatal areas on both sides. Nonparametric Wilcoxon statistical analysis was performed between the BP values from the FBP and OSEM methods. Our results showed that the reconstruction methods have a statistical significant BP values difference in the total striatum (Z = -2,2787 p = 0.005), right striatum (Z = -2,602 p = 0.009) and left striatum (Z= 2,746 p = 0.006). The effect size was calculated to see if there influence in this test: the 'large effect size' for all measurements was observed (total striatum r= -0.51; right striatum r= -0.48; left striatum r= -0.50). FBP is the usual method of reconstruction for brain SPECT images, and our results showed influence of the OSEM method in BP. It is concluded that the method of image reconstruction adopted should be standardized to avoid incorrect evaluations of BP values using ["9"9"mTc]TRODAT-1. (author)

  17. Semiquantitative evaluation of {sup 99}mTctrodat1 binding potential by two methods of SPECT image reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Leite, Melissa Furlaneto Lellis; Reis, Marilia Alves dos; Oliveira, Cassio Miri; Castiglioni, Mario Luiz Vieira; Bressan, Rodrigo Affonseca, E-mail: mefurlaneto@hotmail.com, E-mail: rodrigoabressan@gmail.com, E-mail: mario.castiglioni@uol.com.br [Universidade Federal de Sao Paulo (UNIFESP), SP (Brazil)

    2017-11-01

    TRODAT-1 is a radiopharmaceutical derived from tropane and linked to Technetium-99m ([{sup 99m}Tc] TRODAT-1) has been used in studies of dopamine transporter (DAT) in central nervous system. Associated with the SPECT technique of acquisition, is able to detect changes in neurological disorders like Parkinson´s disease, evaluating the binding potential (BP) of DAT. The aim of this study was to evaluate the influence of the image reconstruction methods, Filtered Back Projection (FBP) and iterative reconstruction (OSEM), in BP values at the striatal region in 30 healthy volunteers. Images were analyzed by visual inspection and semi-quantitative analysis. Regions of interest (ROI) were made over striatal areas on both sides. Nonparametric Wilcoxon statistical analysis was performed between the BP values from the FBP and OSEM methods. Our results showed that the reconstruction methods have a statistical significant BP values difference in the total striatum (Z = -2,2787 p = 0.005), right striatum (Z = -2,602 p = 0.009) and left striatum (Z= 2,746 p = 0.006). The effect size was calculated to see if there influence in this test: the 'large effect size' for all measurements was observed (total striatum r= -0.51; right striatum r= -0.48; left striatum r= -0.50). FBP is the usual method of reconstruction for brain SPECT images, and our results showed influence of the OSEM method in BP. It is concluded that the method of image reconstruction adopted should be standardized to avoid incorrect evaluations of BP values using [{sup 99m}Tc]TRODAT-1. (author)

  18. THE POTENTIAL AND LIMITATIONS OF VISUALISATION AS A METHOD IN LEARNING SOCIAL SCIENCES AND HUMANITIES

    Directory of Open Access Journals (Sweden)

    Tatyana T. Sidelnikova

    2016-06-01

    Full Text Available Introduction: the paper is concerned with potential and barriers of application of visualisation as a method in learning social sciences and humanities. Using and employing visual aids becomes the most important resource in modern pedagogical theory and learning process due to the improvement of traditional pedagogical tools and new interpretation of well-known methods. Materials and Methods: the methods of observation, analysis of test results, results of examination session, data of questionnaires were used during the elaboration of the paper. Results: a good visual aid in teaching political science is the smiley as a simplified graphical representation expressing the emotions of a speaker or a writer. Observation, survey and results of examinations indicate that the above visual solutions not only improve students’ knowledge of subjects, but also improve the intellectual activity, contribute to the formation of the methodical approach to learning, associative thinking and creativity. Discussion and Conclusion: visualisation is a sign presentation of the content, functions, structures, stages of a process, a phenomenon through schematisation and associative and illustrative arrays. At the same time it is a way of transforming knowledge into real visual product with the author’s personal touch. Initially, students learn to reflect by drawing the essence of rather abstract concepts such as “parity”, “power” “freedom” etc. Assignments of higher levels involve the use of associative arrays, free images. By doing this, students do not just paint, but on their own initiative work with colours, seek to schematise information, sometimes dressing comments in lyrics.

  19. Showing Value (Editorial

    Directory of Open Access Journals (Sweden)

    Denise Koufogiannakis

    2009-06-01

    Full Text Available When Su Cleyle and I first decided to start Evidence Based Library and Information Practice, one of the things we agreed upon immediately was that the journal be open access. We knew that a major obstacle to librarians using the research literature was that they did not have access to the research literature. Although Su and I are both academic librarians who can access a wide variety of library and information literature from our institutions, we belong to a profession where not everyone has equal access to the research in our field. Without such access to our own body of literature, how can we ever hope for practitioners to use research evidence in their decision making? It would have been contradictory to the principles of evidence based library and information practice to do otherwise.One of the specific groups we thought could use such an open access venue for discovering research literature was school librarians. School librarians are often isolated and lacking access to the research literature that may help them prove to stakeholders the importance of their libraries and their role within schools. Certainly, school libraries have been in decline and the use of evidence to show value is needed. As Ken Haycock noted in his 2003 report, The Crisis in Canada’s School Libraries: The Case for Reform and Reinvestment, “Across the country, teacher-librarians are losing their jobs or being reassigned. Collections are becoming depleted owing to budget cuts. Some principals believe that in the age of the Internet and the classroom workstation, the school library is an artifact” (9. Within this context, school librarians are looking to our research literature for evidence of the impact that school library programs have on learning outcomes and student success. They are integrating that evidence into their practice, and reflecting upon what can be improved locally. They are focusing on students and showing the impact of school libraries and

  20. Standard Test Method for Half-Cell Potentials of Uncoated Reinforcing Steel in Concrete

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2009-01-01

    1.1 This test method covers the estimation of the electrical corrosion potential of uncoated reinforcing steel in field and laboratory concrete, for the purpose of determining the corrosion activity of the reinforcing steel. 1.2 This test method is limited by electrical circuitry. Concrete surface in building interiors and desert environments lose sufficient moisture so that the concrete resistivity becomes so high that special testing techniques not covered in this test method may be required (see 5.1.4.1). Concrete surfaces that are coated or treated with sealers may not provide an acceptable electrical circuit. The basic configuration of the electrical circuit is shown in Fig. 1. 1.3 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It ...

  1. A simple in chemico method for testing skin sensitizing potential of chemicals using small endogenous molecules.

    Science.gov (United States)

    Nepal, Mahesh Raj; Shakya, Rajina; Kang, Mi Jeong; Jeong, Tae Cheon

    2018-06-01

    Among many of the validated methods for testing skin sensitization, direct peptide reactivity assay (DPRA) employs no cells or animals. Although no immune cells are involved in this assay, it reliably predicts the skin sensitization potential of a chemical in chemico. Herein, a new method was developed using endogenous small-molecular-weight compounds, cysteamine and glutathione, rather than synthetic peptides, to differentiate skin sensitizers from non-sensitizers with an accuracy as high as DPRA. The percent depletion of cysteamine and glutathione by test chemicals was measured by an HPLC equipped with a PDA detector. To detect small-size molecules, such as cysteamine and glutathione, a derivatization by 4-(4-dimethylaminophenylazo) benzenesulfonyl chloride (DABS-Cl) was employed prior to the HPLC analysis. Following test method optimization, a cut-off criterion of 7.14% depletion was applied to differentiate skin sensitizers from non-sensitizers in combination of the ratio of 1:25 for cysteamine:test chemical with 1:50 for glutathione:test chemical for the best predictivity among various single or combination conditions. Although overlapping HPLC peaks could not be fully resolved for some test chemicals, high levels of sensitivity (100.0%), specificity (81.8%), and accuracy (93.3%) were obtained for 30 chemicals tested, which were comparable or better than those achieved with DPRA. Copyright © 2018 Elsevier B.V. All rights reserved.

  2. A systemic method for evaluating the potential impacts of floods on network infrastructures

    Directory of Open Access Journals (Sweden)

    J. Eleutério

    2013-04-01

    Full Text Available Understanding network infrastructures and their operation under exceptional circumstances is fundamental for dealing with flood risks and improving the resilience of a territory. This work presents a method for evaluating potential network infrastructure dysfunctions and damage in cases of flooding. In contrast to existing approaches, this method analyses network infrastructures on an elementary scale, by considering networks as a group of elements with specific functions and individual vulnerabilities. Our analysis places assets at the centre of the evaluation process, resulting in the construction of damage-dysfunction matrices based on expert interviews. These matrices permit summarising the different vulnerabilities of network infrastructures, describing how the different components are linked to each other and how they can disrupt the operation of the network. They also identify the actions and resources needed to restore the system to operational status following damage and dysfunctions, an essential point when dealing with the question of resilience. The method promotes multi-network analyses and is illustrated by a French case study. Sixty network experts were interviewed during the analysis of the following networks: drinking water supply, waste water, public lighting, gas distribution and electricity supply.

  3. Advanced neutron imaging methods with a potential to benefit from pulsed sources

    International Nuclear Information System (INIS)

    Strobl, M.; Kardjilov, N.; Hilger, A.; Penumadu, D.; Manke, I.

    2011-01-01

    During the last decade neutron imaging has seen significant improvements in instrumentation, detection and spatial resolution. Additionally, a variety of new applications and methods have been explored. As a consequence of an outstanding development nowadays various techniques of neutron imaging go far beyond a two- and three-dimensional mapping of the attenuation coefficients for a broad range of samples. Neutron imaging has become sensitive to neutron scattering in the small angle scattering range as well as with respect to Bragg scattering. Corresponding methods potentially provide spatially resolved and volumetric data revealing microstructural inhomogeneities, texture variations, crystalline phase distributions and even strains in bulk samples. Other techniques allow for the detection of refractive index distribution through phase sensitive measurements and the utilization of polarized neutrons enables radiographic and tomographic investigations of magnetic fields and properties as well as electrical currents within massive samples. All these advanced methods utilize or depend on wavelength dependent signals, and are hence suited to profit significantly from pulsed neutron sources as will be discussed.

  4. Development and validation of a method to estimate the potential wind erosion risk in Germany

    Science.gov (United States)

    Funk, Roger; Deumlich, Detlef; Völker, Lidia

    2017-04-01

    The introduction of the Cross Compliance (CC) regulations for soil protection resulted in the demand for the classification of the the wind erosion risk on agricultural areas in Germany nationwide. A spatial highly resolved method was needed based on uniform data sets and validation principles, which provides a fair and equivalent procedure for all affected farmers. A GIS-procedure was developed, which derives the site specific wind erosion risk from the main influencing factors: soil texture, wind velocity, wind direction and landscape structure following the German standard DIN 19706. The procedure enables different approaches in the Federal States and comparable classification results. Here, we present the approach of the Federal State of Brandenburg. In the first step a complete soil data map was composed in a grid size of 10 x 10 m. Data were taken from 1.) the Soil quality Appraisal (scale 1:10.000), 2.) the Medium-scale Soil Mapping (MMK, 1:25.000), 3.) extrapolating the MMK, 4.) new Soil quality Appraisal (new areas after coal-mining). Based on the texture and carbon content the wind erosion susceptibility was divided in 6 classes. This map was combined with data of the annual average wind velocity resulting in an increase of the risk classes for wind velocities > 5 ms-1 and a decrease for structure is regarded by allocating a height to each landscape element, corresponding to the described features in the digital "Biotope and Land Use Map". The "hill shade" procedure of ArcGIS was used to set virtual shadows behind the landscape elements for eight directions. The relative frequency of wind from each direction was used as a weighting factor and multiplied with the numerical values of the shadowed cells. Depending on the distance to the landscape element the shadowing effect was combined with the risk classes. The results show that the wind erosion risk is obviously reduced by integrating landscape structures into the risk assessment. After the renewed

  5. Online monitoring method using Equipotential Switching Direct Current potential drop for piping wall loss by flow accelerated corrosion

    International Nuclear Information System (INIS)

    Ryu, Kyung Ha; Lee, Tae Hyun; Kim, Ji Hak; Hwang, Il Soon; Lee, Na Young; Kim, Ji Hyun; Park, Jin Ho; Sohn, Chang Ho

    2010-01-01

    The flow accelerated corrosion (FAC) phenomenon persistently impacts plant reliability and personnel safety. We have shown that Equipotential Switching Direct Current Potential Drop (ES-DCPD) can be employed to detect piping wall loss induced by FAC. It has been demonstrated to have sufficient sensitivity to cover both long and short lengths of piping. Based on this, new FAC screening and inspection approaches have been developed. For example, resolution of ES-DCPD can be adjusted according to its monitoring purpose. The developed method shows good integrity during long test periods. It also shows good reproducibility. The Seoul National University FAC Accelerated Simulation Loop (SFASL) has been constructed for ES-DCPD demonstration purposes. During one demonstration, the piping wall was thinned by 23.7% through FAC for a 13,000 min test period. In addition to the ES-DCPD method, ultrasonic technique (UT) has been applied to SFASL for verification while water chemistry was continually monitored and controlled using electrochemical sensors. Developed electrochemical sensors showed accurate and stable water conditions in the SFASL during the test period. The ES-DCPD results were also theoretically predicted by the Sanchez-Caldera's model. The UT, however, failed to detect thinning because of its localized characteristics. Online UT that covers only local areas cannot assure the detection of wall loss.

  6. Method for assessment of the technical potential of the plant agricultural waste suitable for energy purposes in Bulgaria

    International Nuclear Information System (INIS)

    Georgiev, V.

    2004-01-01

    A method for assessment of technical potential of quantitatively important plant agriculture waste; straw from wheat and barley; corn stalks; sunflower stalks and heads; tobacco stalks; orchard prunings and vineyard prunings suitable for energy purposes for Bulgarian conditions is developed. Data for assessment of the technical potential for 2002 using this method are presented. A comparison between technical potential of mentioned wastes, final energy consumption in agriculture and all branches of Bulgarian economy for 2002 is made. (author)

  7. A new method for detecting interactions between the senses in event-related potentials

    DEFF Research Database (Denmark)

    Gondan, Matthias; Röder, B.

    2006-01-01

    Event-related potentials (ERPs) can be used in multisensory research to determine the point in time when different senses start to interact, for example, the auditory and the visual system. For this purpose, the ERP to bimodal stimuli (AV) is often compared to the sum of the ERPs to auditory (A......) and visual (V) stimuli: AV - (A + V). If the result is non-zero, this is interpreted as an indicator for multisensory interactions. Using this method, several studies have demonstrated auditory-visual interactions as early as 50 ms after stimulus onset. The subtraction requires that A, V, and AV do...... not contain common activity: This activity would be subtracted twice from one ERP and would, therefore, contaminate the result. In the present study, ERPs to unimodal, bimodal, and trimodal auditory, visual, and tactile stimuli (T) were recorded. We demonstrate that (T + TAV) - (TA + TV) is equivalent to AV...

  8. Constructing Tissue Microarrays: Protocols and Methods Considering Potential Advantages and Disadvantages for Downstream Use.

    Science.gov (United States)

    Bingle, Lynne; Fonseca, Felipe P; Farthing, Paula M

    2017-01-01

    Tissue microarrays were first constructed in the 1980s but were used by only a limited number of researchers for a considerable period of time. In the last 10 years there has been a dramatic increase in the number of publications describing the successful use of tissue microarrays in studies aimed at discovering and validating biomarkers. This, along with the increased availability of both manual and automated microarray builders on the market, has encouraged even greater use of this novel and powerful tool. This chapter describes the basic techniques required to build a tissue microarray using a manual method in order that the theory behind the practical steps can be fully explained. Guidance is given to ensure potential disadvantages of the technique are fully considered.

  9. Fast Measurement of Methanol Concentration in Ionic Liquids by Potential Step Method

    Directory of Open Access Journals (Sweden)

    Michael L. Hainstock

    2015-01-01

    Full Text Available The development of direct methanol fuel cells required the attention to the electrolyte. A good electrolyte should not only be ionic conductive but also be crossover resistant. Ionic liquids could be a promising electrolyte for fuel cells. Monitoring methanol was critical in several locations in a direct methanol fuel cell. Conductivity could be used to monitor the methanol content in ionic liquids. The conductivity of 1-butyl-3-methylimidazolium tetrafluoroborate had a linear relationship with the methanol concentration. However, the conductivity was significantly affected by the moisture or water content in the ionic liquid. On the contrary, potential step could be used in sensing methanol in ionic liquids. This method was not affected by the water content. The sampling current at a properly selected sampling time was proportional to the concentration of methanol in 1-butyl-3-methylimidazolium tetrafluoroborate. The linearity still stood even when there was 2.4 M water present in the ionic liquid.

  10. Arsenic: A Review of the Element's Toxicity, Plant Interactions, and Potential Methods of Remediation.

    Science.gov (United States)

    Hettick, Bryan E; Cañas-Carrell, Jaclyn E; French, Amanda D; Klein, David M

    2015-08-19

    Arsenic is a naturally occurring element with a long history of toxicity. Sites of contamination are found worldwide as a result of both natural processes and anthropogenic activities. The broad scope of arsenic toxicity to humans and its unique interaction with the environment have led to extensive research into its physicochemical properties and toxic behavior in biological systems. The purpose of this review is to compile the results of recent studies concerning the metalloid and consider the chemical and physical properties of arsenic in the broad context of human toxicity and phytoremediation. Areas of focus include arsenic's mechanisms of human toxicity, interaction with plant systems, potential methods of remediation, and protocols for the determination of metals in experimentation. This assessment of the literature indicates that controlling contamination of water sources and plants through effective remediation and management is essential to successfully addressing the problems of arsenic toxicity and contamination.

  11. Molecular Methods Used for the Identification of Potentially Probiotic Lactobacillus reuteri Strains

    Directory of Open Access Journals (Sweden)

    Agnes Weiss

    2005-01-01

    Full Text Available Forty potentially probiotic Lactobacillus strains as well as reference strains of different genera were grown under standardised conditions. Cell masses were harvested and DNA was isolated. For identification, all strains were subjected to genus-specific polymerase chain reaction (PCR, and the affiliation with the genus Lactobacillus was confirmed for all isolates. Using two species-specific primer-pairs for Lactobacillus reuteri, specific amplicons were observed for eight of the forty investigated strains. For differentiation, these eight strains as well as the reference strains of the species L. reuteri and closely related species were subjected to randomly amplified polymorphic DNA (RAPD-PCR using fourteen arbitrary primers. Two selected strains as well as probiotic and common reference strains were further investigated applying pulsed field gel electrophoresis (PFGE. With the latter two methods, individual profiles were found for most strains, but no difference between probiotic and common strains could be made out.

  12. Estimating the Technical Potential of Grid-Connected PV Systems in Indonesia : A Comparison of a Method Based on Open Access Data with a Method Based on GIS

    NARCIS (Netherlands)

    Kunaifi, Kunaifi; Reinders, Angelina H.M.E.; Smets, Arno

    2017-01-01

    In this paper, we compare two methods for estimating the technical potential of grid-connected PV systems in Indonesia. One was a method developed by Veldhuis and Renders [1] and the other is a new method using Geographic Information System (GIS) and multi-criteria decision making (MCDM). The first

  13. An Investigation of Applications for Thermodynamic Work Potential Methods: Working Tables and Charts for Estimation of Thermodynamic Work Potential in Equilibrium Mixtures of Jet-A and Air

    Science.gov (United States)

    Mavris, Dimitri; Roth, Bryce; McDonald, Rob

    2002-01-01

    The objective of this report is to provide a tool to facilitate the application of thermodynamic work potential methods to aircraft and engine analysis. This starts with a discussion of the theoretical background underlying these methods, which is then used to derive various equations useful for thermodynamic analysis of aircraft engines. The work potential analysis method is implemented in the form of a set of working charts and tables that can be used to graphically evaluate work potential stored in high-enthalpy gas. The range of validity for these tables is 300 to 36,000 R, pressures between between 0.01 atm and 100 atm, and fuel-air ratios from zero to stoichiometric. The derivations and charts assume mixtures of Jet-A and air as the working fluid. The thermodynamic properties presented in these charts were calculated based upon standard thermodynamic curve fits.

  14. Relativistic Energy Analysis of Five-Dimensional q-Deformed Radial Rosen-Morse Potential Combined with q-Deformed Trigonometric Scarf Noncentral Potential Using Asymptotic Iteration Method

    International Nuclear Information System (INIS)

    Pramono, Subur; Suparmi, A.; Cari, Cari

    2016-01-01

    We study the exact solution of Dirac equation in the hyperspherical coordinate under influence of separable q-deformed quantum potentials. The q-deformed hyperbolic Rosen-Morse potential is perturbed by q-deformed noncentral trigonometric Scarf potentials, where all of them can be solved by using Asymptotic Iteration Method (AIM). This work is limited to spin symmetry case. The relativistic energy equation and orbital quantum number equation l_D_-_1 have been obtained using Asymptotic Iteration Method. The upper radial wave function equations and angular wave function equations are also obtained by using this method. The relativistic energy levels are numerically calculated using Matlab, and the increase of radial quantum number n causes the increase of bound state relativistic energy level in both dimensions D=5 and D=3. The bound state relativistic energy level decreases with increasing of both deformation parameter q and orbital quantum number n_l.

  15. Optimization of potential field method parameters through networks for swarm cooperative manipulation tasks

    Directory of Open Access Journals (Sweden)

    Rocco Furferi

    2016-10-01

    Full Text Available An interesting current research field related to autonomous robots is mobile manipulation performed by cooperating robots (in terrestrial, aerial and underwater environments. Focusing on the underwater scenario, cooperative manipulation of Intervention-Autonomous Underwater Vehicles (I-AUVs is a complex and difficult application compared with the terrestrial or aerial ones because of many technical issues, such as underwater localization and limited communication. A decentralized approach for cooperative mobile manipulation of I-AUVs based on Artificial Neural Networks (ANNs is proposed in this article. This strategy exploits the potential field method; a multi-layer control structure is developed to manage the coordination of the swarm, the guidance and navigation of I-AUVs and the manipulation task. In the article, this new strategy has been implemented in the simulation environment, simulating the transportation of an object. This object is moved along a desired trajectory in an unknown environment and it is transported by four underwater mobile robots, each one provided with a seven-degrees-of-freedom robotic arm. The simulation results are optimized thanks to the ANNs used for the potentials tuning.

  16. A Method to Analyze the Potential of Optical Remote Sensing for Benthic Habitat Mapping

    Directory of Open Access Journals (Sweden)

    Rodrigo A. Garcia

    2015-10-01

    Full Text Available Quantifying the number and type of benthic classes that are able to be spectrally identified in shallow water remote sensing is important in understanding its potential for habitat mapping. Factors that impact the effectiveness of shallow water habitat mapping include water column turbidity, depth, sensor and environmental noise, spectral resolution of the sensor and spectral variability of the benthic classes. In this paper, we present a simple hierarchical clustering method coupled with a shallow water forward model to generate water-column specific spectral libraries. This technique requires no prior decision on the number of classes to output: the resultant classes are optically separable above the spectral noise introduced by the sensor, image based radiometric corrections, the benthos’ natural spectral variability and the attenuating properties of a variable water column at depth. The modeling reveals the effect reducing the spectral resolution has on the number and type of classes that are optically distinct. We illustrate the potential of this clustering algorithm in an analysis of the conditions, including clustering accuracy, sensor spectral resolution and water column optical properties and depth that enabled the spectral distinction of the seagrass Amphibolis antartica from benthic algae.

  17. A Simple and Rapid Method to Evaluate Potentially Mineralizable Nitrogen in Sewage Sludge Amended Calcareous Soils

    Directory of Open Access Journals (Sweden)

    Yazdan Lotfi

    2005-06-01

    Full Text Available Potentially mineralizable nitrogen (PMN can be usually considered as labile nitrogen. Measurement of PMN is expensive and time consuming; therefore, a simpler and more rapid alternative may facilitate routine laboratory analysis. The objective of this study was to determine the relationship between PMN and biological index of nitrogen availability (BINA. The studied soil was previously treated with 0, 25, and 100 tons ha-1 of sewage sludge with 0, 1, 2 and 3 consecutive years of application. Soil samples were taken 6 months after the latest application. PMN was measured according to Stanford and Smith procedure (20 weeks of aerobic incubation with 2 weeks leaching intervals and BINA measured as described by Bundy and Meisinger (7 days of anaerobic incubation at 40˚ C followed by extraction of NH4+. Results showed that PMN was significantly correlated with BINA (r = 0.938, P

  18. Simple and easy method to evaluate uptake potential of nanoparticles in mammalian cells using a flow cytometric light scatter analysis.

    Science.gov (United States)

    Suzuki, Hiroshi; Toyooka, Tatsushi; Ibuki, Yuko

    2007-04-15

    Many classes of nanoparticles have been synthesized and widely applied, however, there is a serious lack of information concerning their effects on human health and the environment. Considering that their use will increase, accurate and cost-effective measurement techniques for characterizing "nanotoxicity" are required. One major toxicological concern is that nanoparticles are easily taken up in the human body. In this study, we developed a method of evaluating the uptake potential of nanosized particles using flow cytometric light scatter. Suspended titanium dioxide (TiO2) particles (5, 23, or 5000 nm) were added to Chinese hamster ovary cells. Observation by confocal laser scanning microscopy showed that the TiO2 particles easily moved to the cytoplasm of the cultured mammalian cells, not to the nucleus. The intensity of the side-scattered light revealed that the particles were taken up in the cells dose-, time-, and size-dependently. In addition, surface-coating of TiO2 particles changed the uptake into the cells, which was accurately reflected in the intensity of the side-scattered light. The uptake of other nanoparticles such as silver (Ag) and iron oxide (Fe3O4) also could be detected. This method could be used for the initial screening of the uptake potential of nanoparticles as an index of "nanotoxicity".

  19. A new calculational method to assess the therapeutic potential of Auger electron emission

    International Nuclear Information System (INIS)

    Humm, J.L.; Charlton, D.E.

    1989-01-01

    This paper discusses a new computer code to estimate the efficacy of Auger electron sources in cancer therapy. Auger electron emission accompanies the decay of many radionuclides already commonly used in nuclear medicine, for example; 99m Tc and 201 Tl. The range of these electrons is in general sub-cellular, therefore, the toxicity of the source depends on the site of decay relative to the genetic material of the cell. Electron track structure methods have been used which enable the study of energy deposition from Auger sources down to the Angstrom level. A figure for the minimum energy required per single strand break is obtained by fitting our energy deposition calculations for 125 I decays in a model of the DNA to experimental data on break lengths from 125 I labeled plasmid fragments. This method is used to investigate the efficiency of double strand break production by other Auger sources which have potential value for therapy. The high RBE of Auger sources depends critically on the distance between the source and target material. The application of Auger emitters for therapy may necessitate a carrier molecule that can append the source to the DNA. Many DNA localizing agents are known in the field of chemotherapy, some of which could be carrier molecules for Auger sources; the halogenated thymidine precursors are under scrutiny in this field. The activation of Auger cascades in situ by high energy, collimated X ray and neutron beams is also assessed

  20. Effective Fragment Potential Method for H-Bonding: How To Obtain Parameters for Nonrigid Fragments.

    Science.gov (United States)

    Dubinets, Nikita; Slipchenko, Lyudmila V

    2017-07-20

    Accuracy of the effective fragment potential (EFP) method was explored for describing intermolecular interaction energies in three dimers with strong H-bonded interactions, formic acid, formamide, and formamidine dimers, which are a part of HBC6 database of noncovalent interactions. Monomer geometries in these dimers change significantly as a function of intermonomer separation. Several EFP schemes were considered, in which fragment parameters were prepared for a fragment in its gas-phase geometry or recomputed for each unique fragment geometry. Additionally, a scheme in which gas-phase fragment parameters are shifted according to relaxed fragment geometries is introduced and tested. EFP data are compared against the coupled cluster with single, double, and perturbative triple excitations (CCSD(T)) method in a complete basis set (CBS) and the symmetry adapted perturbation theory (SAPT). All considered EFP schemes provide a good agreement with CCSD(T)/CBS for binding energies at equilibrium separations, with discrepancies not exceeding 2 kcal/mol. However, only the schemes that utilize relaxed fragment geometries remain qualitatively correct at shorter than equilibrium intermolecular distances. The EFP scheme with shifted parameters behaves quantitatively similar to the scheme in which parameters are recomputed for each monomer geometry and thus is recommended as a computationally efficient approach for large-scale EFP simulations of flexible systems.

  1. Development of a novel method to detect a potential inhalation of nanoaerosols

    Energy Technology Data Exchange (ETDEWEB)

    Marie-Desvergne, C; Mossuz, V [LABM, Medical Biology Analyses Laboratory, CEA, 17 rue des Martyrs, 38054 Grenoble Cedex 9 (France); Tardif, F; Motellier, S, E-mail: veronique.mossuz@cea.fr [NanoChemistry and NanoSafety Laboratory, LITEN, CEA, 17 rue des Martyrs, 38054 Grenoble Cedex 9 (France)

    2011-07-06

    In the context of the precautionary principle for engineered nanoparticles, a test able to verify the non exposure of individuals to nanoaerosols seems to be of great interest, especially for workers involved with nanomaterials. A novel method is proposed to detect the presence of nanoparticles in the nose. Different materials, including paper and polycarbonate, have been tested for their sampling efficiency towards ZnO nanoparticles. The detection of nanoparticles is performed by elemental analysis using Total Reflection X-Ray Fluorescence (TXRF). For an optimal sensitivity of the TXRF signal, samples have to be deposited on a smooth surface. Therefore, different materials have been compared as sample carrier. The results indicate that pure paper is the most efficient material for sampling nanoparticles (ZnO), while the use of polycarbonate, and even more flexible polyester, as sample carrier allows a better sensitivity for TXRF analysis. Therefore, the sampling device made of paper is digested under slightly acidic conditions in a microwave oven after collection, and the resulting solution is deposited on polyester for TXRF analysis. Internal calibration is performed thanks to an addition of Rb to the samples. The proposed method allows the chemical identification of nanoparticles deposited in the nose: a qualitative signature of a potential nanoaerosol inhalation.

  2. A Stochastic Inversion Method for Potential Field Data: Ant Colony Optimization

    Science.gov (United States)

    Liu, Shuang; Hu, Xiangyun; Liu, Tianyou

    2014-07-01

    Simulating natural ants' foraging behavior, the ant colony optimization (ACO) algorithm performs excellently in combinational optimization problems, for example the traveling salesman problem and the quadratic assignment problem. However, the ACO is seldom used to inverted for gravitational and magnetic data. On the basis of the continuous and multi-dimensional objective function for potential field data optimization inversion, we present the node partition strategy ACO (NP-ACO) algorithm for inversion of model variables of fixed shape and recovery of physical property distributions of complicated shape models. We divide the continuous variables into discrete nodes and ants directionally tour the nodes by use of transition probabilities. We update the pheromone trails by use of Gaussian mapping between the objective function value and the quantity of pheromone. It can analyze the search results in real time and promote the rate of convergence and precision of inversion. Traditional mapping, including the ant-cycle system, weaken the differences between ant individuals and lead to premature convergence. We tested our method by use of synthetic data and real data from scenarios involving gravity and magnetic anomalies. The inverted model variables and recovered physical property distributions were in good agreement with the true values. The ACO algorithm for binary representation imaging and full imaging can recover sharper physical property distributions than traditional linear inversion methods. The ACO has good optimization capability and some excellent characteristics, for example robustness, parallel implementation, and portability, compared with other stochastic metaheuristics.

  3. Fair and efficient tariffs for wind energy : principles, method, proposal, data and potential consequences in France

    International Nuclear Information System (INIS)

    Chabot, B.

    2001-01-01

    In 2000, the government of France announced a national energy plan that included the installation of 5,000 to 10,000 MW of wind power by 2010. It also announced a new system based on fixed tariffs that would replace the EOLE 2005 calls for tenders for projects under 12 MW. This paper described the principles and methods used to develop this fair and efficient tariff system for wind energy in France. The Agence de l'Environnement et de la Maitrise de l'Energie (ADEME) uses the Profitability Index Method to help define a wind energy tariff system for wind power plants under 12 MW. This paper presents some figures of the related over-cost incurred with the new tariff system which makes it possible for energy developers in France to develop huge wind potential at a pace equal to other countries with fixed premium prices. The over-cost of the new tariff system is not too high, plus it could be passed equally over all consumers of electricity. The tariff system will help France comply with its national, European and international commitments regarding climate change and with the future European directive on electricity generated from renewable energy sources. 8 refs., 1 tab., 4 figs

  4. Measurement of the total antioxidant potential in chronic obstructive pulmonary diseases with a novel automated method

    International Nuclear Information System (INIS)

    Ceylan, E.; Gencer, M.; Uzer, E.; Celik, H.

    2007-01-01

    To determine the oxidative and antioxidative status of plasma of patients with chronic obstructive pulmonary disease (COPD) and to compare these values with healthy smokers and healthy non-smokers control subjects using a more recently developed automated measurement method. This study involved 40 COPD patients, 25 healthy smokers, and 25 non-healthy smokers who attended the Chest Disease Outpatient Clinic in Harran University Research Hospital, Turkey between the period March 2006 and June 2006. We calculated the total antioxidant potential (TAOP) to determine the antioxidative status of plasma and we measured the total peroxide levels to determine the oxidative status of plasma. The TAOP of plasma was significantly lower in patients with COPD than in healthy smokers and healthy non-smokers (p< 0.001). In contrast, the mean total peroxide level of plasma was significantly higher in COPD patients than in healthy smokers and healthy non-smokers (p<0.001). We found a decreased in TAOP COPD patients using a simple, rapid and reliably automated colorimetric assay, which may suitable for use in routine clinical biochemistry laboratory and considerably facilitates the assessment of this useful clinical parameter. We suggest that this novel method may be used as a routine test to evaluate and follow-up the levels of oxidative stress in COPD. (author)

  5. Advantages and limitations of potential methods for the analysis of bacteria in milk: a review.

    Science.gov (United States)

    Tabit, Frederick Tawi

    2016-01-01

    Contamination concerns in the dairy industry are motivated by outbreaks of disease in humans and the inability of thermal processes to eliminate bacteria completely in processed products. HACCP principles are an important tool used in the food industry to identify and control potential food safety hazards in order to meet customer demands and regulatory requirements. Milk testing is of importance to the milk industry regarding quality assurance and monitoring of processed products by researchers, manufacturers and regulatory agencies. Due to the availability of numerous methods used for analysing the microbial quality of milk in literature and differences in priorities of stakeholders, it is sometimes confusing to choose an appropriate method for a particular analysis. The objective of this paper is to review the advantages and disadvantages of selected techniques that can be used in the analysis of bacteria in milk. SSC, HRMA, REP, and RAPD are the top four techniques which are quick and cost-effective and possess adequate discriminatory power for the detection and profiling of bacteria. The following conclusions were arrived at during this review: HRMA, REP and RFLP are the techniques with the most reproducible results, and the techniques with the most discriminatory power are AFLP, PFGE and Raman Spectroscopy.

  6. Application of commercial sensor manufacturing methods for NOx/NH3 mixed potential sensors for emissions control

    Energy Technology Data Exchange (ETDEWEB)

    Brosha, Eric L [Los Alamos National Laboratory; Mukundan, Rangachary [Los Alamos National Laboratory; Nelson, Mark A [Los Alamos National Laboratory; Sekhar, Praveen [Los Alamos National Laboratory; Williamson, Todd [Los Alamos National Laboratory; Garzon, Fernando H [Los Alamos National Laboratory

    2009-01-01

    The purpose of this research effort is to develop a low cost on-board Nitrogen Oxide (NO{sub x})/Ammonia (NH{sub 3}) sensor that can not only be used for emissions control but has the potential to improve efficiency through better monitoring of the combustion process and feedback control in both vehicle and stationary systems. Over the past decade, Los AJamos National Laboratory (LANL) has developed a unique class of electrochemical gas sensors for the detection of carbon monoxide, hydrocarbons, hydrogen and nitrogen oxides. These sensors are based on the mixed-potential phenomenon and are a modification of the existing automotive lambda (oxygen) sensor and have the potential to meet the stringent sensitivity, selectivity and stability requirements of an on-board emissions/engine control sensor system. The current state of the art LANL technology is based on the stabilization of the electrochemical interfaces and relies on an externally heated, hand-made, tape cast device. We are now poised to apply our patented sensing principles in a mass production sensor platform that is more suitable for real world engine-out testing such as on dynamometers for vehicle applications and for exhaust-out testing in heavy boilers/SCR systems in power plants. In this present work, our goal is to advance towards commercialization of this technology by packaging the unique LANL sensor design in a standard automotive sensor-type platform. This work is being performed with the help of a leading US technical ceramics firm, utilizing commercial manufacturing techniques. Initial tape cast platforms with screen printed metal oxide and Pt sensor electrodes have shown promising results but also clearly show the need for us to optimize the electrode and electrolyte compositions/morphologies and interfaces of these devices in order to demonstrate a sensitive, selective, and stable NO{sub x} sensor. Our previous methods and routes to preparing stable and reproducible mixed potential sensors

  7. A universal method to assess the potential of phosphorus loss from soil to aquatic ecosystems.

    Science.gov (United States)

    Pöthig, Rosemarie; Behrendt, Horst; Opitz, Dieter; Furrer, Gerhard

    2010-02-01

    Phosphorus loss from terrestrial to the aquatic ecosystems contributes to eutrophication of surface waters. To maintain the world's vital freshwater ecosystems, the reduction of eutrophication is crucial. This needs the prevention of overfertilization of agricultural soils with phosphorus. However, the methods of risk assessment for the P loss potential from soils lack uniformity and are difficult for routine analysis. Therefore, the efficient detection of areas with a high risk of P loss requires a simple and universal soil test method that is cost effective and applicable in both industrialized and developing countries. Soils from areas which varied highly in land use and soil type were investigated regarding the degree of P saturation (DPS) as well as the equilibrium P concentration (EPC(0)) and water-soluble P (WSP) as indicators for the potential of P loss. The parameters DPS and EPC(0) were determined from P sorption isotherms. Our investigation of more than 400 soil samples revealed coherent relationships between DPS and EPC(0) as well as WSP. The complex parameter DPS, characterizing the actual P status of soil, is accessible from a simple standard measurement of WSP based on the equation [Formula: see text]. The parameter WSP in this equation is a function of remaining phosphorous sorption capacity/total accumulated phosphorous (SP/TP). This quotient is independent of soil type due to the mutual compensation of the factors SP and TP. Thus, the relationship between DPS and WSP is also independent of soil type. The degree of P saturation, which reflects the actual state of P fertilization of soil, can be calculated from the easily accessible parameter WSP. Due to the independence from soil type and land use, the relation is valid for all soils. Values of WSP, which exceed 5 mg P/kg soil, signalize a P saturation between 70% and 80% and thus a high risk of P loss from soil. These results reveal a new approach of risk assessment for P loss from soils to

  8. Volatile organic compounds in pesticide formulations: Methods to estimate ozone formation potential

    Science.gov (United States)

    Zeinali, Mazyar; McConnell, Laura L.; Hapeman, Cathleen J.; Nguyen, Anh; Schmidt, Walter F.; Howard, Cody J.

    2011-05-01

    The environmental fate and toxicity of active ingredients in pesticide formulations has been investigated for many decades, but relatively little research has been conducted on the fate of pesticide co-formulants or inerts. Some co-formulants are volatile organic compounds (VOCs) and can contribute to ground-level ozone pollution. Effective product assessment methods are required to reduce emissions of the most reactive VOCs. Six emulsifiable concentrate pesticide products were characterized for percent VOC by thermogravimetric analysis (TGA) and gas chromatography-mass spectrometry (GC-MS). TGA estimates exceeded GC-MS by 10-50% in all but one product, indicating that for some products a fraction of active ingredient is released during TGA or that VOC contribution was underestimated by GC-MS. VOC profiles were examined using TGA-Fourier transform infrared (FTIR) evolved gas analysis and were compared to GC-MS results. The TGA-FTIR method worked best for products with the simplest and most volatile formulations, but could be developed into an effective product screening tool. An ozone formation potential ( OFP) for each product was calculated using the chemical composition from GC-MS and published maximum incremental reactivity ( MIR) values. OFP values ranged from 0.1 to 3.1 g ozone g -1 product. A 24-h VOC emission simulation was developed for each product assuming a constant emission rate calculated from an equation relating maximum flux rate to vapor pressure. Results indicate 100% VOC loss for some products within a few hours, while other products containing less volatile components will remain in the field for several days after application. An alternate method to calculate a product OFP was investigated utilizing the fraction of the total mass of each chemical emitted at the end of the 24-h simulation. The ideal assessment approach will include: 1) unambiguous chemical composition information; 2) flexible simulation models to estimate emissions under

  9. Sensitivity analysis and parameter estimation for distributed hydrological modeling: potential of variational methods

    Directory of Open Access Journals (Sweden)

    W. Castaings

    2009-04-01

    Full Text Available Variational methods are widely used for the analysis and control of computationally intensive spatially distributed systems. In particular, the adjoint state method enables a very efficient calculation of the derivatives of an objective function (response function to be analysed or cost function to be optimised with respect to model inputs.

    In this contribution, it is shown that the potential of variational methods for distributed catchment scale hydrology should be considered. A distributed flash flood model, coupling kinematic wave overland flow and Green Ampt infiltration, is applied to a small catchment of the Thoré basin and used as a relatively simple (synthetic observations but didactic application case.

    It is shown that forward and adjoint sensitivity analysis provide a local but extensive insight on the relation between the assigned model parameters and the simulated hydrological response. Spatially distributed parameter sensitivities can be obtained for a very modest calculation effort (~6 times the computing time of a single model run and the singular value decomposition (SVD of the Jacobian matrix provides an interesting perspective for the analysis of the rainfall-runoff relation.

    For the estimation of model parameters, adjoint-based derivatives were found exceedingly efficient in driving a bound-constrained quasi-Newton algorithm. The reference parameter set is retrieved independently from the optimization initial condition when the very common dimension reduction strategy (i.e. scalar multipliers is adopted.

    Furthermore, the sensitivity analysis results suggest that most of the variability in this high-dimensional parameter space can be captured with a few orthogonal directions. A parametrization based on the SVD leading singular vectors was found very promising but should be combined with another regularization strategy in order to prevent overfitting.

  10. Computing wave functions in multichannel collisions with non-local potentials using the R-matrix method

    Science.gov (United States)

    Bonitati, Joey; Slimmer, Ben; Li, Weichuan; Potel, Gregory; Nunes, Filomena

    2017-09-01

    The calculable form of the R-matrix method has been previously shown to be a useful tool in approximately solving the Schrodinger equation in nuclear scattering problems. We use this technique combined with the Gauss quadrature for the Lagrange-mesh method to efficiently solve for the wave functions of projectile nuclei in low energy collisions (1-100 MeV) involving an arbitrary number of channels. We include the local Woods-Saxon potential, the non-local potential of Perey and Buck, a Coulomb potential, and a coupling potential to computationally solve for the wave function of two nuclei at short distances. Object oriented programming is used to increase modularity, and parallel programming techniques are introduced to reduce computation time. We conclude that the R-matrix method is an effective method to predict the wave functions of nuclei in scattering problems involving both multiple channels and non-local potentials. Michigan State University iCER ACRES REU.

  11. Microencapsulation as a novel delivery method for the potential antidiabetic drug, Probucol.

    Science.gov (United States)

    Mooranian, Armin; Negrulj, Rebecca; Chen-Tan, Nigel; Al-Sallami, Hesham S; Fang, Zhongxiang; Mukkur, T K; Mikov, Momir; Golocorbin-Kon, Svetlana; Fakhoury, Marc; Watts, Gerald F; Matthews, Vance; Arfuso, Frank; Al-Salami, Hani

    2014-01-01

    In previous studies, we successfully designed complex multicompartmental microcapsules as a platform for the oral targeted delivery of lipophilic drugs in type 2 diabetes (T2D). Probucol (PB) is an antihyperlipidemic and antioxidant drug with the potential to show benefits in T2D. We aimed to create a novel microencapsulated formulation of PB and to examine the shape, size, and chemical, thermal, and rheological properties of these microcapsules in vitro. Microencapsulation was carried out using the Büchi-based microencapsulating system developed in our laboratory. Using the polymer, sodium alginate (SA), empty (control, SA) and loaded (test, PB-SA) microcapsules were prepared at a constant ratio (1:30). Complete characterizations of microcapsules, in terms of morphology, thermal profiles, dispersity, and spectral studies, were carried out in triplicate. PB-SA microcapsules displayed uniform and homogeneous characteristics with an average diameter of 1 mm. The microcapsules exhibited pseudoplastic-thixotropic characteristics and showed no chemical interactions between the ingredients. These data were further supported by differential scanning calorimetric analysis and Fourier transform infrared spectral studies, suggesting microcapsule stability. The new PB-SA microcapsules have good structural properties and may be suitable for the oral delivery of PB in T2D. Further studies are required to examine the clinical efficacy and safety of PB in T2D.

  12. A Method for Measuring Fast Time Evolutions of the Plasma Potential by Means of a Simple Emissive Probe

    DEFF Research Database (Denmark)

    Iizuka, S.; Michelsen, Poul; Juul Rasmussen, Jens

    1981-01-01

    potential is measured across a high resistance. During each sweep of the probe voltage, the changing of the sign of the probe current, which is sampled at a specific time, gives rise to a negative pulse, driving the pen-lift of an X-Y recorder. Since the real floating potential is measured where the probe......A method is presented for obtaining the temporal evolution of the plasma potential, which is assumed to be given by the floating potential of a simple emissive probe. The construction of the probe is also described. The method avoids the slow time response of the usual technique where the floating...

  13. Assessment of the microbial growth potential of slow sand filtrate with the biomass production potential test in comparison with the assimilable organic carbon method.

    Science.gov (United States)

    van der Kooij, Dick; Veenendaal, Harm R; van der Mark, Ed J; Dignum, Marco

    2017-11-15

    Slow sand filtration is the final treatment step at four surface-water supplies in the Netherlands. The microbial growth potential (MGP) of the finished water was measured with the assimilable organic carbon (AOC) method using pure cultures and the biomass production potential (BPP) test. In the BPP test, water samples were incubated untreated at 25 °C and the active-biomass concentration was measured by adenosine tri-phosphate (ATP) analysis. Addition of a river-water inoculum improved the test performance and characteristic growth and maintenance profiles of the water were obtained. The maximum ATP concentration attained within seven days and the cumulative biomass production after 14 days of incubation (BPC 14 , d ng ATP L -1 ) showed highly significant and strong linear relationships with the AOC in the slow sand filtrates. The lowest AOC and BPC 14 levels were observed in the supplies applying dune filtration without ozonation in post treatment, with AOC/TOC = 1.7 ± 0.3 μg acetate-C equivalents mg -1 C and BPC 14 /TOC = 16.3 ± 2.2 d ng ATP mg -1 C, corresponding with 1.2 ± 0.19 ng ATP mg -1 C. These characteristics may represent the lowest specific MGP of natural organic matter achievable by biofiltration at temperatures ≤20 °C. The AOC and BPC 14 concentrations in the slow sand filtrate of the supply treating lake water by ozonation with granular-activated-carbon filtration and slow sand filtration as post treatment increased with decreasing temperature. The BPP test revealed that this slow sand filtrate sampled at 2 °C contained growth-promoting compounds that were not detected with the AOC test. These observations demonstrate the utility of the BPP test for assessing the MGP of drinking water and show the performance limits of biofiltration for MGP reduction. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Cost-Effective Method for Free-Energy Minimization in Complex Systems with Elaborated Ab Initio Potentials.

    Science.gov (United States)

    Bistafa, Carlos; Kitamura, Yukichi; Martins-Costa, Marilia T C; Nagaoka, Masataka; Ruiz-López, Manuel F

    2018-05-22

    We describe a method to locate stationary points in the free-energy hypersurface of complex molecular systems using high-level correlated ab initio potentials. In this work, we assume a combined QM/MM description of the system although generalization to full ab initio potentials or other theoretical schemes is straightforward. The free-energy gradient (FEG) is obtained as the mean force acting on relevant nuclei using a dual level strategy. First, a statistical simulation is carried out using an appropriate, low-level quantum mechanical force-field. Free-energy perturbation (FEP) theory is then used to obtain the free-energy derivatives for the target, high-level quantum mechanical force-field. We show that this composite FEG-FEP approach is able to reproduce the results of a standard free-energy minimization procedure with high accuracy, while simultaneously allowing for a drastic reduction of both computational and wall-clock time. The method has been applied to study the structure of the water molecule in liquid water at the QCISD/aug-cc-pVTZ level of theory, using the sampling from QM/MM molecular dynamics simulations at the B3LYP/6-311+G(d,p) level. The obtained values for the geometrical parameters and for the dipole moment of the water molecule are within the experimental error, and they also display an excellent agreement when compared to other theoretical estimations. The developed methodology represents therefore an important step toward the accurate determination of the mechanism, kinetics, and thermodynamic properties of processes in solution, in enzymes, and in other disordered chemical systems using state-of-the-art ab initio potentials.

  15. Preparation of Raspberry-like Superhydrophobic SiO2 Particles by Sol-gel Method and Its Potential Applications

    Directory of Open Access Journals (Sweden)

    Xu Gui-Long

    2011-12-01

    Full Text Available Raspberry‐like SiO2 particles with a nano‐micro‐binary structure were prepared by a simple sol‐gel method using tetraethoxysilane (TEOS and methyltriethoxysilane (MTES as precursors. The chemical components and morphology of the SiO2 particles were characterized by Fourier transform infrared spectroscopy (FT‐IR and a Transmission electron microscope (TEM. The surface topography and wetting behaviour of the raspberry‐like SiO2 surface were observed with a Scanning electron microscope (SEM and studied by the water/oil contact angle (CA, respectively. The thermal stability of the prepared SiO2 particles was characterized by TGA analysis. The results show that the highly dispersed SiO2 particles initially prepared by the sol‐gel method turn into raspberry‐like particles with during the aging process. The raspberry‐like SiO2 particles show superhydrophobicity and superoleophilicity across a wide range of pH values. The SiO2 particles were thermally stable up to 475°C, while above this temperature the hydrophobicity decreases and finally becomes superhydrophobic when the temperature reaches 600°C. The raspberry‐like SiO2 particles which were prepared have potential applications in the fields of superhydrophobic surfaces, water‐oil separation, anti‐corrosion and fluid transportation.

  16. Development of Air Quality Impact Assessment Method of Potential Volcanic Hazard near the Korean Peninsula

    Science.gov (United States)

    Sunwoo, Y.; Kim, Y. J.; Kim, D.; Park, J. E.; Hong, K. H.

    2016-12-01

    Many volcanos are located within 1,500 km of Korea which implies that a potential disaster is always possible. Several eruption precursors were observed rather recently at Mt. Baekdu, which has sparked intensive research on volcanic disasters in Korea. For assessment of potential volcanic hazard in Korea, we developed classification method of volcanic eruption dates using the Hybrid Single-Particle Lagrangian Integrated Trajectory model (HYSPLIT-4) regarding air quality impact. And, we conducted 3 dimensional chemistry transport modeling for selected eruption dates. WRF-ARW(version 3.6.1) meteorological modeling was employed for high resolution HYSPLIT input meteorological data,. The modeling domain covers Northeast Asia including Korea, Japan, east China, and part of Russia. Forward trajectories were calculated every 3 hours for 1 year (2010) and the trajectories were initiated from 3 volcanoes, Mt. Baekdu, Mt. Aso, and Mt. Tarumae. Selected eruption dates were classified into 5 classes using 4 parameters, PBL, trajectory retention time, initial trajectory altitude and exposed population. The number of significant days for volcanic eruption impact were 7 for Mt. Baekdu (spring and fall), 7 for Mt. Aso (summer), 1 for Mt. Tarumae (spring), and these were classified as class A, with the highest risk of incurring severe air pollution episodes in the receptor area. In addition, we analyzed the spatio-temporal distributions of these trajectories in the receptor area to help determine the period and domain of the volcanic eruption 3 dimensional chemistry transport modeling. Using class A eruption dates, we conducted CMAQ(v5.0.2) modeling for calculate full chemical reactions of volcanic gases and ashes in troposphere.

  17. Methods of mineral potential assessment of uranium deposits: A mineral systems approach

    International Nuclear Information System (INIS)

    Jaireth, S.

    2014-01-01

    deposit). The five questions include: i) what is the architecture and size of the system; ii) what is P-T and geodynamic history of the system; iii) what is the nature of the fluids and fluid reservoirs in the system; iv) what is the nature of fluid pathways; and v) what is the chemistry of metal transport and deposition in space as well as time. Analysis of fertile mineral systems can provide useful information on geological processes essential to form an economic mineral deposit in an area. Mappable features of these processes in geological datasets can then be used to estimate probabilities visualised in the form of mineral potential, prospectivity and favourability maps. The probabilities (levels of mineral potential, favourability index) can be either shown using non-numerical (high, moderate and low), ordinal (numbers expressing ranking) and cardinal (numbers expressing quantities) scales. This paper will discuss advantages and disadvantages of various GIS-based methods of qualitative assessment and will also present a number of case studies illustrating mineral potential assessment of uranium deposits carried out in Geoscience Australia. (author)

  18. A clinically feasible method for the detection of potential collision in proton therapy

    Energy Technology Data Exchange (ETDEWEB)

    Zou Wei; Lin Haibo; Plastaras, John P.; Wang Huanshu; Bui, Viet; Vapiwala, Neha; McDonough, James; Tochner, Zelig; Both, Stefan [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States); Department of Radiation Oncology, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States) and Department of Mechanical Engineering, Drexel University, Philadelphia, Pennsylvania 19104 (United States); Department of Radiation Oncology, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States)

    2012-11-15

    Purpose: Potential collision between the patient/couch and the gantry could delay the start of the treatment and reduce clinical efficiency. The ability to accurately detect possible collisions during the treatment planning phase is desired. Such collision detection should account for the specific proton gantry design, the treatment beam configuration, couch orientation, and the patient specific geometry. In this paper the authors developed an approach to detect possible patient-machine collisions using patient treatment plan data. Methods: The geometry of the machine and the patient was reconstructed relative to the isocenter of the proton treatment room. The surface contour of the gantry was first captured from the proton computer aided design and reconstructed to account for specific gantry rotation, snout position, collimator rotation, and range compensator dimensions based on the patient treatment plan data. The patient body and couch contours were captured from the patient's CT DICOM structure file. They were reconstructed relative to the isocenter taking into account treatment couch rotation. For potential collision that occurs at body portions where no CT images exist, scout images are used to construct the body contour. A software program was developed using a ray casting algorithm that was applied to detect collisions by determining if any of the patient and couch contour points fall into the spatial polygons formed by the proton gantry surfaces. Results: Twenty-four patient plans with or without potential collisions were retrospectively identified and analyzed using the collision detection software. In addition, five collision cases were artificially generated using an anthropomorphic phantom. The program successfully detected the collisions in all cases. The calculation time for each case was within 20 s. The software program was implemented in the authors' clinic to detect patient-gantry or gantry-couch collisions in the treatment planning

  19. Assessing the potential of random forest method for estimating solar radiation using air pollution index

    International Nuclear Information System (INIS)

    Sun, Huaiwei; Gui, Dongwei; Yan, Baowei; Liu, Yi; Liao, Weihong; Zhu, Yan; Lu, Chengwei; Zhao, Na

    2016-01-01

    Highlights: • Models based on random forests for daily solar radiation estimation are proposed. • Three sites within different air pollution index conditions are considered. • Performance of random forests is better than that of empirical methodologies. • Special attention is given to the use of air pollution index. • The potential of air pollution index is assessed by random forest models. - Abstract: Simulations of solar radiation have become increasingly common in recent years because of the rapid global development and deployment of solar energy technologies. The effect of air pollution on solar radiation is well known. However, few studies have attempting to evaluate the potential of the air pollution index in estimating solar radiation. In this study, meteorological data, solar radiation, and air pollution index data from three sites having different air pollution index conditions are used to develop random forest models. We propose different random forest models with and without considering air pollution index data, and then compare their respective performance with that of empirical methodologies. In addition, a variable importance approach based on random forest is applied in order to assess input variables. The results show that the performance of random forest models with air pollution index data is better than that of the empirical methodologies, generating 9.1–17.0% lower values of root-mean-square error in a fitted period and 2.0–17.4% lower values of root-mean-square error in a predicted period. Both the comparative results of different random forest models and variance importance indicate that applying air pollution index data is improves estimation of solar radiation. Also, although the air pollution index values varied largely from season to season, the random forest models appear more robust performances in different seasons than different models. The findings can act as a guide in selecting used variables to estimate daily solar

  20. Unified method to integrate and blend several, potentially related, sources of information for genetic evaluation.

    Science.gov (United States)

    Vandenplas, Jérémie; Colinet, Frederic G; Gengler, Nicolas

    2014-09-30

    A condition to predict unbiased estimated breeding values by best linear unbiased prediction is to use simultaneously all available data. However, this condition is not often fully met. For example, in dairy cattle, internal (i.e. local) populations lead to evaluations based only on internal records while widely used foreign sires have been selected using internally unavailable external records. In such cases, internal genetic evaluations may be less accurate and biased. Because external records are unavailable, methods were developed to combine external information that summarizes these records, i.e. external estimated breeding values and associated reliabilities, with internal records to improve accuracy of internal genetic evaluations. Two issues of these methods concern double-counting of contributions due to relationships and due to records. These issues could be worse if external information came from several evaluations, at least partially based on the same records, and combined into a single internal evaluation. Based on a Bayesian approach, the aim of this research was to develop a unified method to integrate and blend simultaneously several sources of information into an internal genetic evaluation by avoiding double-counting of contributions due to relationships and due to records. This research resulted in equations that integrate and blend simultaneously several sources of information and avoid double-counting of contributions due to relationships and due to records. The performance of the developed equations was evaluated using simulated and real datasets. The results showed that the developed equations integrated and blended several sources of information well into a genetic evaluation. The developed equations also avoided double-counting of contributions due to relationships and due to records. Furthermore, because all available external sources of information were correctly propagated, relatives of external animals benefited from the integrated

  1. Oral rinse as a potential method to culture Candida isolate from AIDS patients

    Directory of Open Access Journals (Sweden)

    Desiana Radithia

    2011-12-01

    Full Text Available Background: Candida isolate is easily sampled from oral cavity by swabbing directly on the candidiasis lesion, to be smeared onto slides for direct examination or cultured in a growth medium. This method is by far the gold standard for defining candidiasis diagnosis. However it is difficult to apply on sensitive patients and almost impossible on patients showing no clinical appearance of oral candidiasis. AIDS patients are very prone to candida infection and have a tendency of repetitive infection involving mixed species. As many candida species show different susceptibility to anti-fungal agents, it is necessary to identify the species causing the infection in the management of oral candidiasis. Oral rinse is a suggested method to obtain candida isolate to be cultured for further analysis such as species identification. This method is simple and less risky on infection transmission as less tools are required in the procedure. Purpose: This study aimed to assess the application of oral rinse as an alternative method to culture Candida isolate from AIDS patients. Methods: A cross-sectional observative study was conducted in HIV/AIDS in-Patient Facility of Intermediate Care Unit for Infection Disease, Dr. Soetomo Hospital Surabaya. Fourteen stadium 4 AIDS patients matching criteria were swabbed on 1/3-posterior of the tongue, and then given 10 ml phosphate buffer saline to rinse vigorously for 15 seconds. Both specimens were cultured on Sabouraud’s dextrose agar and colony growth was observed. Results: Candida colonies were able to grow from all 14 isolates (100% by both methods. Qualitatively, cultures from oral rinse specimens were more populated than cultures from swab specimens. Conclusion: Oral rinse is an applicable technique to obtain Candida species isolate. This technique is safe, easy, non-invasive, and needs less tools therefore less risky for HIV transmission.Latar belakang: Isolat Candida mudah diambil dengan cara mengusap lesi

  2. Potential Suitable Methods for Measuring the Effects of Animal-Assisted Activities and Therapy: a Review

    Directory of Open Access Journals (Sweden)

    Machová K.

    2016-09-01

    Full Text Available Dogs are companions of humans since time beyond memory and their use in rehabilitation processes is increasingly frequent. Dogs can be used for animal-assisted activities (AAA as well as animal-assisted therapy (AAT. The effects, however, have not been fully demonstrated, reasons for this including difficulties in providing evidence of positive action. According to previous studies, there is a decrease in heart and respiratory rate, blood pressure reduction, more positive mood as well as warming of muscles, which promotes relaxation of spastic areas. Regulation of hormone levels might also occur as a result of AAA/AAT. Indeed, increases in oxytocin levels and decreases of cortisol have been found. However, a unified methodology for clear measuring the entire impact of AAA/AAT on patients is missing. This survey evaluated different methods for measuring the effects of AAA/AAT, with results showing that the most suitable ones, selected on the basis of the effect of rehabilitation, comprise thermography, spectral analysis of heart rate, electromyography (EMG, polyelectromyography (PEMG, and blood sampling. Because AAT making use of dogs has not yet been recognized as an official method of treatment, it is very important to find out objective means to evidence its beneficial effects. Highlights:

  3. A vector field method on the distorted Fourier side and decay for wave equations with potentials

    CERN Document Server

    Donninger, Roland

    2016-01-01

    The authors study the Cauchy problem for the one-dimensional wave equation \\partial_t^2 u(t,x)-\\partial_x^2 u(t,x)+V(x)u(t,x)=0. The potential V is assumed to be smooth with asymptotic behavior V(x)\\sim -\\tfrac14 |x|^{-2}\\mbox{ as } |x|\\to \\infty. They derive dispersive estimates, energy estimates, and estimates involving the scaling vector field t\\partial_t+x\\partial_x, where the latter are obtained by employing a vector field method on the âeoedistortedâe Fourier side. In addition, they prove local energy decay estimates. Their results have immediate applications in the context of geometric evolution problems. The theory developed in this paper is fundamental for the proof of the co-dimension 1 stability of the catenoid under the vanishing mean curvature flow in Minkowski space; see Donninger, Krieger, Szeftel, and Wong, âeoeCodimension one stability of the catenoid under the vanishing mean curvature flow in Minkowski spaceâe, preprint arXiv:1310.5606 (2013).

  4. Development of a piping thickness monitoring system using equipotential switching direct current potential drop method

    International Nuclear Information System (INIS)

    Kyung Ha, Ryu; Na Young, Lee; Il Soon, Hwang

    2007-01-01

    As nuclear power plants age, low alloy steel piping undergoes wall thickness reduction due to Flow Accelerated Corrosion (FAC). Persisting pipe rupture accidents prompted thinned pipe management programs. As a consequence extensive inspection activities are made based on the Ultrasonic Technique (UT). As the inspection points increase, time is needed to cover required inspection areas. In this paper, we present the Wide Range Monitoring (WiRM) concept with Equipotential Switching Direct Current Potential Drop (ES-DCPD) method by which FAC-active areas can be screened for detailed UT inspections. To apply ES-DCPD, we developed an electric resistance network model and electric field model based on Finite Element Analysis (FEA) to verify its feasibility. Experimentally we measured DCPD of the pipe elbow and confirmed the validity using UT inspections. For a more realistic validation test, we designed a high temperature flow test loop with environmental parameters turned for FAC simulation in the laboratory. Using electrochemical monitoring of water chemistry and local flow velocity prediction by computational fluid dynamic model, FAC rate is estimated. Based on the FAC prediction model and the simulation loop test, we plan to demonstrate the applicability of ES-DCPD in the PWR secondary environment. (authors)

  5. Charge transfer interaction using quasiatomic minimal-basis orbitals in the effective fragment potential method

    International Nuclear Information System (INIS)

    Xu, Peng; Gordon, Mark S.

    2013-01-01

    The charge transfer (CT) interaction, the most time-consuming term in the general effective fragment potential method, is made much more computationally efficient. This is accomplished by the projection of the quasiatomic minimal-basis-set orbitals (QUAMBOs) as the atomic basis onto the self-consistent field virtual molecular orbital (MO) space to select a subspace of the full virtual space called the valence virtual space. The diagonalization of the Fock matrix in terms of QUAMBOs recovers the canonical occupied orbitals and, more importantly, gives rise to the valence virtual orbitals (VVOs). The CT energies obtained using VVOs are generally as accurate as those obtained with the full virtual space canonical MOs because the QUAMBOs span the valence part of the virtual space, which can generally be regarded as “chemically important.” The number of QUAMBOs is the same as the number of minimal-basis MOs of a molecule. Therefore, the number of VVOs is significantly smaller than the number of canonical virtual MOs, especially for large atomic basis sets. This leads to a dramatic decrease in the computational cost

  6. Obtaining of Solids With Potential Corrosion Inhibitory Effects by Electrocoagulation Vinasse Methods

    Directory of Open Access Journals (Sweden)

    Dra. Elaine Ojeda-Armaignac

    2015-11-01

    Full Text Available In this paper, electrocoagulation experiments are performed at different vinasse samples with a viewto obtaining solids with potential corrosion inhibitory effects. Experimental tests were performed with samples of complex sugar «Argeo Martínez» Guantánamo province, «Urbano Noris Holguín province, in the antique complex Destillery-Brewery «Hatuey» of the province of Santiago de Cuba and in the rum factory of Appleton» in Kingston Jamaica. Electrocoagulation preliminary tests performed with the vinasse from distilleries of Santiago de Cuba, Guantánamo and Holguín allowed the definition of thevariables and their domain, which were considered in the design of experiments to obtain the most favorable conditions of operation. Preliminary experiments corroborated that increasing the current density and pH, increase linearly solids obtained and current density values exceeding 0,194 5 A/cm2 are not feasible because they increase the energy consumption process and the increase of solids is negligible. Validation of electrocoagulation method was demonstrated with results of the experimentaldesign from Jamaica´s vinasse, that were similar to those obtained with Cuban vinasse; reaching favorable conditions for operation at current density of 0,194 5/cm2, pH equal to 8,97 and time 5,6 min, resulting in 15,42 g of total solids for a minimum consumption of 8,44 kW·h/kg.

  7. Exploring the potential of the cosmic-ray neutron method to measure interception storage dynamics

    Science.gov (United States)

    Jakobi, Jannis; Bogena, Heye; Huisman, Johan Alexander; Diekkrüger, Bernd; Vereecken, Harry

    2017-04-01

    Cosmic-ray neutron soil moisture probes are an emerging technology that relies on the negative correlation between near-surface fast neutron counts and soil moisture content. Hydrogen atoms in the soil, which are mainly present as water, moderate the secondary neutrons on the way back to the surface. Any application of this method needs to consider the sensitivity of the neutron counts to additional sources of hydrogen (e.g. above- and below-ground biomass, humidity of the lower atmosphere, lattice water of the soil minerals, organic matter and water in the litter layer, intercepted water in the canopy, and soil organic matter). In this study, we analyzed the effects of canopy-intercepted water on the cosmic-ray neutron counts. For this, an arable field cropped with sugar beet was instrumented with several cosmic-ray neutron probes and a wireless sensor network with more than 140 in-situ soil moisture sensors. Additionally rainfall interception was estimated using a new approach coupling throughfall measurements and leaf wetness sensors. The derived interception storage was used to correct for interception effects on cosmic ray neutrons to enhance soil water content prediction. Furthermore, the potential for a simultaneous prediction of above- and below-ground biomass, soil moisture and interception was tested.

  8. An Effective Method for Detecting Potential Woodland Vernal Pools Using High-Resolution LiDAR Data and Aerial Imagery

    Science.gov (United States)

    Effective conservation of woodland vernal pools – important components of regional amphibian diversity and ecosystem services – depends on locating and mapping these pools accurately. Current methods for identifying potential vernal pools are primarily based on visual interpretat...

  9. Novel Method for Sizing Metallic Bottom Crack Depth Using Multi-frequency Alternating Current Potential Drop Technique

    OpenAIRE

    Li Yuting; Gan Fangji; Wan Zhengjun; Liao Junbi; Li Wenqiang

    2015-01-01

    Potential drop techniques are of two types: the direct current potential drop (DCPD) technique and alternating current potential drop (ACPD) technique, and both of them are used in nondestructive testing. ACPD, as a kind of valid method in sizing metal cracks, has been applied to evaluate metal structures. However, our review of most available approaches revealed that some improvements can be done in measuring depth of metal bottom crack by means of ACPD, such as accuracy and sensitivity of s...

  10. On the use of a Hamiltonian with projected potential for the calculation of scattering wave functions : Methods and general properties

    International Nuclear Information System (INIS)

    Colle, R.; Simonucci, S.

    1996-01-01

    The theoretical framework of a method that utilizes a projected potential operator to construct scattering wave functions is presented. Theorems and spectral properties of a Hamiltonian with the potential energy operator represented in terms of L'2(R'3)-functions are derived. The computational advantages offered by the method for calculating spectroscopic quantities, like resonance energies, decay probabilities and photoionization cross-sections, are discussed

  11. Magnetism of hexagonal close-packed nickel calculated by full-potential linearized augmented plane wave method

    International Nuclear Information System (INIS)

    Tian, F.; Tian, H.; Whitmore, L.; Ye, L.Y.

    2015-01-01

    The energy dependent on volume of hexagonal close-packed (hcp) nickel with different magnetism is calculated by full-potential linearized augmented plane wave method. Based on the calculation ferromagnetic state is found to be the most stable state. The magnetic moment of hcp Ni is calculated and compared to those calculated by different pseudo-potential methods. Furthermore, it is also compared to that of face-centered cubic (fcc) one with the reason discussed

  12. A method for locating potential tree-planting sites in urban areas: a case study of Los Angeles, USA

    Science.gov (United States)

    Chunxia Wua; Qingfu Xiaoa; Gregory E. McPherson

    2008-01-01

    A GIS-based method for locating potential tree-planting sites based on land cover data is introduced. Criteria were developed to identify locations that are spatially available for potential tree planting based on land cover, sufficient distance from impervious surfaces, a minimum amount of pervious surface, and no crown overlap with other trees. In an ArcGIS...

  13. A new method for temperature-field reconstruction during ultrasound-monitored cryosurgery using potential-field analogy.

    Science.gov (United States)

    Thaokar, Chandrajit; Rossi, Michael R; Rabin, Yoed

    2016-02-01

    The current study aims at developing computational tools in order to gain information about the thermal history in areas invisible to ultrasound imaging during cryosurgery. This invisibility results from the high absorption rate of the ultrasound energy by the frozen region, which leads to an apparent opacity in the cryotreated area and a shadow behind it. A proof-of-concept for freezing-front estimation is demonstrated in the current study, using the new potential-field analogy method (PFAM). This method is further integrated with a recently developed temperature-field reconstruction method (TFRM) to estimate the temperature distribution within the frozen region. This study uses prostate cryosurgery as a developmental model and trans-rectal ultrasound imaging as a choice of practice. Results of this study indicate that the proposed PFAM is a viable and computationally inexpensive solution to estimate the extent of freezing in the acoustic shadow region. Comparison of PFAM estimations and experimental data shows an average mismatch of less than 2 mm in freezing-front location, which is comparable to the uncertainty in ultrasound imaging. Comparison of the integrated PFAM + TFRM scheme with a full-scale finite-elements analysis (FEA) indicates an average mismatch of 0.9 mm for the freezing front location and 0.1 mm for the lethal temperature isotherm of -45 °C. Comparison of the integrated PFAM + TFRM scheme with experimental temperature measurements show a difference in the range of 2 °C and 6 °C for selected points of measurement. Results of this study demonstrate the integrated PFAM + TFRM scheme as a viable and computationally inexpensive means to gain information about the thermal history in the frozen region during ultrasound-monitored cryosurgery. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. A scoping review of the potential for chart stimulated recall as a clinical research method.

    Science.gov (United States)

    Sinnott, Carol; Kelly, Martina A; Bradley, Colin P

    2017-08-22

    Chart-stimulated recall (CSR) is a case-based interviewing technique, which is used in the assessment of clinical decision-making in medical education and professional certification. Increasingly, clinical decision-making is a concern for clinical research in primary care. In this study, we review the prior application and utility of CSR as a technique for research interviews in primary care. Following Arksey & O'Malley's method for scoping reviews, we searched seven databases, grey literature, reference lists, and contacted experts in the field. We excluded studies on medical education or competence assessment. Retrieved citations were screened by one reviewer and full texts were ordered for all potentially relevant abstracts. Two researchers independently reviewed full texts and performed data extraction and quality appraisal if inclusion criteria were met. Data were collated and summarised using a published framework on the reporting of qualitative interview techniques, which was chosen a priori. The preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines informed the review report. From an initial list of 789 citations, eight studies using CSR in research interviews were included in the review: six from North America, one from the Netherlands, and one from Ireland. The most common purpose of included studies was to examine the influence of guidelines on physicians' decisions. The number of interviewees ranged from seven to twenty nine, while the number of charts discussed per interview ranged from one to twelve. CSR gave insights into physicians' reasoning for actions taken or not taken; the unrecorded social and clinical influences on decisions; and discrepancies between physicians' real and perceived practice. Ethical concerns and the training and influence of the researcher were poorly discussed in most of the studies. Potential pitfalls included the risk of recall, selection and observation biases. Despite the proven validity

  15. Zeta potential and Raman studies of PVP capped Bi2S3 nanoparticles synthesized by polyol method

    Science.gov (United States)

    Tarachand, Sathe, Vasant G.; Okram, Gunadhor S.

    2018-05-01

    Here we report the synthesis and characterisation of polyvinylpyrrolidone (PVP) capped Bi2S3 nanoparticles via one step catalyst-free polyol method. Raman spectroscopy, dynamic light scattering and zeta potential analysis were performed on it. Rietveld refinement of powder XRD of PVP capped samples confirmed the formation of single phase orthorhombic Bi2S3 for all PVP capped samples. The presence of eight obvious Raman modes further confirmed the formation of stoichiometric Bi2S3. Dynamic light scattering (DLS) studies show a clear increase in hydrodynamic diameter for samples made with increasing PVP concentration. Particle size obtained from DLS and XRD (using Scherrer's formula) combine with change in full width half maxima of Raman modes collectively suggest overall improvement in crystallinity and quality of product on introducing PVP. In zeta potential (ζ) measurement, steric hindrance of carbon chains plays very crucial role and a systematic reduction of ζ value is observed for samples made with decreasing PVP concentration. An isoelectric point is obtained for sample made with low PVP (1g). Present results are likely to open a window for its medical and catalytic applications.

  16. Hierarchy of model Kohn–Sham potentials for orbital-dependent functionals: A practical alternative to the optimized effective potential method

    International Nuclear Information System (INIS)

    Kohut, Sviataslau V.; Staroverov, Viktor N.; Ryabinkin, Ilya G.

    2014-01-01

    We describe a method for constructing a hierarchy of model potentials approximating the functional derivative of a given orbital-dependent exchange-correlation functional with respect to electron density. Each model is derived by assuming a particular relationship between the self-consistent solutions of Kohn–Sham (KS) and generalized Kohn–Sham (GKS) equations for the same functional. In the KS scheme, the functional is differentiated with respect to density, in the GKS scheme—with respect to orbitals. The lowest-level approximation is the orbital-averaged effective potential (OAEP) built with the GKS orbitals. The second-level approximation, termed the orbital-consistent effective potential (OCEP), is based on the assumption that the KS and GKS orbitals are the same. It has the form of the OAEP plus a correction term. The highest-level approximation is the density-consistent effective potential (DCEP), derived under the assumption that the KS and GKS electron densities are equal. The analytic expression for a DCEP is the OCEP formula augmented with kinetic-energy-density-dependent terms. In the case of exact-exchange functional, the OAEP is the Slater potential, the OCEP is roughly equivalent to the localized Hartree–Fock approximation and related models, and the DCEP is practically indistinguishable from the true optimized effective potential for exact exchange. All three levels of the proposed hierarchy require solutions of the GKS equations as input and have the same affordable computational cost

  17. Application of biclustering of gene expression data and gene set enrichment analysis methods to identify potentially disease causing nanomaterials

    Directory of Open Access Journals (Sweden)

    Andrew Williams

    2015-12-01

    Full Text Available Background: The presence of diverse types of nanomaterials (NMs in commerce is growing at an exponential pace. As a result, human exposure to these materials in the environment is inevitable, necessitating the need for rapid and reliable toxicity testing methods to accurately assess the potential hazards associated with NMs. In this study, we applied biclustering and gene set enrichment analysis methods to derive essential features of altered lung transcriptome following exposure to NMs that are associated with lung-specific diseases. Several datasets from public microarray repositories describing pulmonary diseases in mouse models following exposure to a variety of substances were examined and functionally related biclusters of genes showing similar expression profiles were identified. The identified biclusters were then used to conduct a gene set enrichment analysis on pulmonary gene expression profiles derived from mice exposed to nano-titanium dioxide (nano-TiO2, carbon black (CB or carbon nanotubes (CNTs to determine the disease significance of these data-driven gene sets.Results: Biclusters representing inflammation (chemokine activity, DNA binding, cell cycle, apoptosis, reactive oxygen species (ROS and fibrosis processes were identified. All of the NM studies were significant with respect to the bicluster related to chemokine activity (DAVID; FDR p-value = 0.032. The bicluster related to pulmonary fibrosis was enriched in studies where toxicity induced by CNT and CB studies was investigated, suggesting the potential for these materials to induce lung fibrosis. The pro-fibrogenic potential of CNTs is well established. Although CB has not been shown to induce fibrosis, it induces stronger inflammatory, oxidative stress and DNA damage responses than nano-TiO2 particles.Conclusion: The results of the analysis correctly identified all NMs to be inflammogenic and only CB and CNTs as potentially fibrogenic. In addition to identifying several

  18. Investigation of toxigenic potential of fungal species by the use of simple screening method

    Directory of Open Access Journals (Sweden)

    Bočarov-Stančić Aleksandra S.

    2009-01-01

    Full Text Available Potential for the biosynthesis of aflatoxin B1 (AFLB1, ochratoxin A (OTA, diacetoxyscirpenol (DAS, T-2 toxin (T2, and zearalenone (ZON was investigated in different fungal species belonging to the genera: Aspergillus, Fusarium and Penicillium. The majority of investigated isolates originated from cereal grains, crushed oil soybean seed and fodder mixtures. The simple screening method developed by Filtenborg et al. (1983 was applied with few modifications concerning the type of the medium and cultivation temperature. In order to optimise the biosynthetic conditions for different mycotoxins, the following control cultures, known as mycotin producers were used: OTA - A. ochraceus CBS 108.08, DAS - F. semitectum (SL-B i SL-C, T2 - F. sporotrichioides (ITM-391, M-1-1, R-2301 and ZON - F. graminearum (GZ-LES. The fungi were cultivated on the standard medium (YESA - 2% yeast extract, 15% sucrose and 2% agar, pH 6.5, three modifications of the basic medium (YESAZn - the standard medium supplemented with 0.23 mg/l ZnSO4 x 5 H2O; PPSA - the medium in which yeast extract was replaced with peptone-1; PPSAZn - the medium in which yeast extract was replaced with peptone-1 and supplemented with 0.23 mg/l ZnSO4 x 5 H2O, and the potato-dextrose agar (PDA. The earlier biosynthesis of tested mycotoxins was recorded under the following cultivation conditions of fungal species: AFLB1 - after 14 days on PDA at 27±1°C, OTA - after 10 days on YESA and YESAZn at 27±1°C, DAS - after 10 days on PPSA and PPSAZn at 27±1°C, T2 - after 7 days on PPSAZn and PPSA at room temperature (20-24°C, and ZON - after 1 week on YESA and YESAZn at room temperature (21-24°C.

  19. Methods of removing uranium from drinking water. 1. A literature survey. 2. Present municipal water treatment and potential removal methods

    International Nuclear Information System (INIS)

    Drury, J.S.; Michelson, D.; Ensminger, J.T.; Lee, S.Y.; White, S.K.

    1982-12-01

    Literature was searched for methods of removing uranium from drinking water. U.S. manufacturers and users of water-treatment equipment and products were also contacted regarding methods of removing uranium from potable water. Based on the results of these surveys, it was recommended that untreated, partially treated, and finished water samples from municipal water-treatment facilities be analyzed to determine the extent of removal of uranium by presently used procedures, and that additional laboratory studies be performed to determine what changes are needed to maximize the effectiveness of treatments that are already in use in existing water-treatment plants

  20. Comparative study of in situ methods for potential and actual evapotranspiration determination and their calculation by simulation model

    International Nuclear Information System (INIS)

    Kolev, B.

    2006-01-01

    Four in situ methods for potential and actual evapotranspiration determining were compared: neutron gauge, tensiometers, gypsum blocks and lysimeters. The actual and potential evapotranspiration were calculated by water balance equation and by using a simulation model for their determination. The aim of this study was mainly pointed on calculations of water use efficiency and transpiration coefficient in potential production situation. This makes possible to choose the best way for water consumption optimization for a given crop. The final results find with the best of the methods could be used for applying the principles of sustainable agricultural production in random object of Bulgarian agricultural area

  1. Potential Analysis of Thunderstorm Occurrence Using SWEAT Method at Meteorology Station Sultan Iskandar Muda

    Directory of Open Access Journals (Sweden)

    Ulfah Kurnia

    2018-01-01

    radiosonde data has been done on two monsoon, they are summer and winter to forecast potential occurrence of thunderstorm since period April-December 2016 and January-March 2017. The radiosonde data was got from Meteorological Station of Sultan Iskandar Muda that had been measured every two times a day. The measuring time is 00Z and 12Z. Radiosonde data is processed by Software Rawinsonde Observation (RAOB versi 5.7 until get information about the atmosphere parameters such as temperature, dew point, and wind speed. The atmosphere parameters can be used to forecast the potential occurrence of thunderstorm for the next twelve hours, using SWEAT (Severe Weather Threat method until get SWEAT Index for every radiosonde measurement. Based on the research that has been done, the range of SWEAT Index for Meteorological Station of Sultan Iskandar Muda area is about 39,8 - 355,4. The result of analysis SWEAT method verified with the actual data (synop data that is observed at Meteorological Station of Sultan Iskandar Muda and get the suitability of persentase between forecast data with actual condition is 58,62% - 66, 67%. Keyword: Thunderstorm, SWEAT Method, SWEAT Index, Synop Data, Meteorological REFERENCE Budiarti, M., Muslim, M., dan Ilhamsyah, Y. 2012. Studi Indeks Stabilitas Udara Terhadap Prediksi Kejadian Badai Guntur (Thunderstorm di Wilayah Stasiun Meteorologi Cengkareng Banten. Jurnal Meteorologi dan Geofisika Vol. 13 No. 2 tahun 2012 : 111-117. Duhah, S., Andrius, dan Tauladani, R. 2010. Penggunaan Metode SWEAT Untuk Perkiraan Kejadian Badai Guntur di Atas Kota Pekanbaru Pada Bulan Oktober Hingga November 2009. Jurnal Photon Vol. 1 No. 1. Fadholi, A. 2012. Analisa Kondisi Atmosfer pada Kejadian Cuaca Ekstrem Hujan Es (Hail. Jurnal Ilmu Fisika Indonesia Volume 1 Nomor 2 (D. Fitrianti, N., Fauziyah, A. R., dan Fadila, R. 2015. Analisa Pola Hidup dan Spasial Awan Cumulonimbus Menggunakan Citra Radar (Studi Kasus Wilayah Bima Bulan Januari 2015. Jurnal Meteorologi Klimatologi

  2. Steady state method to determine unsaturated hydraulic conductivity at the ambient water potential

    Science.gov (United States)

    HUbbell, Joel M.

    2014-08-19

    The present invention relates to a new laboratory apparatus for measuring the unsaturated hydraulic conductivity at a single water potential. One or more embodiments of the invented apparatus can be used over a wide range of water potential values within the tensiometric range, requires minimal laboratory preparation, and operates unattended for extended periods with minimal supervision. The present invention relates to a new laboratory apparatus for measuring the unsaturated hydraulic conductivity at a single water potential. One or more embodiments of the invented apparatus can be used over a wide range of water potential values within the tensiometric range, requires minimal laboratory preparation, and operates unattended for extended periods with minimal supervision.

  3. Antioxidant Potential of the Giant Mushroom, Macrocybe gigantea (Agaricomycetes), from India in Different Drying Methods.

    Science.gov (United States)

    Gaur, Tanvi; Rao, P B

    2016-01-01

    Free radicals are responsible for several diseases like cancer, atherosclerosis, gastric ulcers, and several others. Studies have shown that mushrooms possess antioxidant activity and Macrocybe gigantea was recently added to the list of mushrooms under cultivation in India. The methanolic extracts were prepared from lyophilized and oven-dried samples of MA1 and MA2 strains of M. gigantea and their antioxidant properties were studied. MA2 showed comparatively higher total antioxidant activity (111.88 µg/mg) than MA1 (97.00 µg/mg). The scavenging activity on 2,2'-diphenyl picryl hydrazyl free radical (74.41%), ferrous chelating (83.74%), reducing power (0.371), and superoxide anion radical (72.05%) was significantly higher in freeze-dried MA2 than MA1 at 200 µg/mL. Correspondingly, the EC50 values were lower in freeze-dried states (96.03 µg/mL, 95.00 µg/mL, and 68.12 µg/mL in MA2 and 105.12 µg/mL, 109.8 µg/mL, and 74.60 µg/mL in MA1) than in oven-dried states (97.97 µg/mL, 120.2 µg/mL, and 125.33 µg/mL in MA2 and 108.3 µg/mL, 131.2 µg/mL, and 147.5 µg/mL in MA1, respectively). In addition, total phenolic, total flavonoid, and ortho-dihydroxy phenol content was examined and their values were comparatively higher in freeze-dried MA2 (18.00 mg/g of gallic acid equivalents, 1.67 mg/g of quercetin equivalents, and 1.10 mg/g of catechol equivalents, respectively) than in MA1 and oven-dried states in both strains. Further, MA2 showed lower EC50 values in freeze-dried samples than MA1 and oven-dried states in both strains. These results suggested that MA2 contains higher antioxidant potential than MA1 and freeze-drying by lyophilization retains higher antioxidants than heat drying by a hot air oven in both the strains; thus, they can be a good source of nutraceuticals.

  4. MiOXSYS: a novel method of measuring oxidation reduction potential in semen and seminal plasma.

    Science.gov (United States)

    Agarwal, Ashok; Sharma, Rakesh; Roychoudhury, Shubhadeep; Du Plessis, Stefan; Sabanegh, Edmund

    2016-09-01

    To measure oxidative reduction potential (ORP) in semen and seminal plasma and to establish their reference levels. ORP levels were measured in semen and seminal plasma. Tertiary hospital. Twenty-six controls and 33 infertile men. None. Static ORP (sORP) and capacitance ORP (cORP) were measured in semen and seminal plasma at time 0 and 120 minutes. Correlation of ORP was assessed between [1] semen and seminal plasma and [2] time 0 and 120 minutes. The association with sperm parameters was studied in (a) controls and (b) infertile patients, and a receiver operating characteristic curve was generated to establish the sORP cutoff. Semen sORP and cORP levels were associated with seminal plasma levels at time 0 and time 120 minutes. In controls and infertile patients, an inverse relationship of sORP levels was established with concentration and total sperm count in semen as well as seminal plasma at time 0 and 120 minutes. Classification of subjects based on sperm motility showed that subjects with abnormal motility present with poor concentration, total count, morphology, and elevated levels of semen and seminal plasma sORP at time 120 minutes. The sORP cutoff of 1.48 in semen and 2.09 in seminal plasma based on motility was able to distinguish subjects with normal semen quality from those with abnormal semen quality. The MiOXSYS System can reliably measure ORP levels in semen and seminal plasma. ORP levels are not affected by semen age, making this new technology easy to employ in a clinical setting. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  5. The analysis of metabolites in human sweat: analytical methods and potential application to investigation of pressure ischaemia of soft tissues.

    Science.gov (United States)

    Taylor, R P; Polliack, A A; Bader, D L

    1994-01-01

    A straightforward technique was developed for sweat collection applicable to tissues subjected to external load without introducing distortion of underlying tissues, and for analysis of six metabolites in the collected sweat. Chloride was measured colorimetrically and lactate, urea and urate by enzymatic methods on a centrifugal analyser. Sodium and potassium were measured by flame photometry. The methods showed good precision, recovery and linearity. To assess the technique sweat was collected: (i) from the sacrum, ischium, forearm and calf in healthy individuals at 32 degrees C for 1 h; (ii) from the sacrum of healthy subjects at ambient temperature for 9 h; (iii) at ambient temperature from the sacrum of a patient with a history of pressure sores. Sweat rates were greater at the sacrum and ischium than the calf or forearm. There were differences in the concentrations of lactate and urea between sites but these were smaller when expressed as amount secreted. Sweat rates were significantly lower in groups (ii) and (iii), but sweat could be collected reliably. This technique has potential clinical application to the investigation of susceptibility to pressure sores.

  6. Triple-component nanocomposite films prepared using a casting method: Its potential in drug delivery

    Directory of Open Access Journals (Sweden)

    Sadia Gilani

    2018-04-01

    Full Text Available The purpose of this study was to fabricate a triple-component nanocomposite system consisting of chitosan, polyethylene glycol (PEG, and drug for assessing the application of chitosan–PEG nanocomposites in drug delivery and also to assess the effect of different molecular weights of PEG on nanocomposite characteristics. The casting/solvent evaporation method was used to prepare chitosan–PEG nanocomposite films incorporating piroxicam-β-cyclodextrin. In order to characterize the morphology and structure of nanocomposites, X-ray diffraction technique, scanning electron microscopy, thermogravimetric analysis, and Fourier transmission infrared spectroscopy were used. Drug content uniformity test, swelling studies, water content, erosion studies, dissolution studies, and anti-inflammatory activity were also performed. The permeation studies across rat skin were also performed on nanocomposite films using Franz diffusion cell. The release behavior of films was found to be sensitive to pH and ionic strength of release medium. The maximum swelling ratio and water content was found in HCl buffer pH 1.2 as compared to acetate buffer of pH 4.5 and phosphate buffer pH 7.4. The release rate constants obtained from kinetic modeling and flux values of ex vivo permeation studies showed that release of piroxicam-β-cyclodextrin increased with an increase in concentration of PEG. The formulation F10 containing 75% concentration of PEG showed the highest swelling ratio (3.42±0.02 in HCl buffer pH 1.2, water content (47.89±1.53% in HCl buffer pH 1.2, maximum cumulative drug permeation through rat skin (2405.15±10.97 μg/cm2 in phosphate buffer pH 7.4, and in vitro drug release (35.51±0.26% in sequential pH change mediums, and showed a significantly (p<0.0001 higher anti-inflammatory effect (0.4 cm. It can be concluded from the results that film composition had a particular impact on drug release properties. The different molecular weights of PEG have a

  7. Sensitivity of potential evapotranspiration estimation to the Thornthwaite and Penman-Monteith methods in the study of global drylands

    Science.gov (United States)

    Yang, Qing; Ma, Zhuguo; Zheng, Ziyan; Duan, Yawen

    2017-12-01

    Drylands are among those regions most sensitive to climate and environmental changes and human-induced perturbations. The most widely accepted definition of the term dryland is a ratio, called the Surface Wetness Index (SWI), of annual precipitation to potential evapotranspiration (PET) being below 0.65. PET is commonly estimated using the Thornthwaite (PET Th) and Penman-Monteith equations (PET PM). The present study compared spatiotemporal characteristics of global drylands based on the SWI with PET Th and PET PM. Results showed vast differences between PET Th and PET PM; however, the SWI derived from the two kinds of PET showed broadly similar characteristics in the interdecadal variability of global and continental drylands, except in North America, with high correlation coefficients ranging from 0.58 to 0.89. It was found that, during 1901-2014, global hyper-arid and semi-arid regions expanded, arid and dry sub-humid regions contracted, and drylands underwent interdecadal fluctuation. This was because precipitation variations made major contributions, whereas PET changes contributed to a much lesser degree. However, distinct differences in the interdecadal variability of semi-arid and dry sub-humid regions were found. This indicated that the influence of PET changes was comparable to that of precipitation variations in the global dry-wet transition zone. Additionally, the contribution of PET changes to the variations in global and continental drylands gradually enhanced with global warming, and the Thornthwaite method was found to be increasingly less applicable under climate change.

  8. Exploring the methods of data analysis in multifocal visual evoked potentials

    DEFF Research Database (Denmark)

    Malmqvist, Lasse; Santiago de Abreu, Lucimar; Fraser, C.

    2016-01-01

    Purpose: The multifocal visual evoked potential (mfVEP) provides a topographical assessment of visual function, which has already shown potential for use in patients with glaucoma and multiple sclerosis. However, the variability in mfVEP measurements has limited its broader application. The purpo...

  9. Studying learning in the healthcare setting: the potential of quantitative diary methods.

    Science.gov (United States)

    Ciere, Yvette; Jaarsma, Debbie; Visser, Annemieke; Sanderman, Robbert; Snippe, Evelien; Fleer, Joke

    2015-08-01

    Quantitative diary methods are longitudinal approaches that involve the repeated measurement of aspects of peoples' experience of daily life. In this article, we outline the main characteristics and applications of quantitative diary methods and discuss how their use may further research in the field of medical education. Quantitative diary methods offer several methodological advantages, such as measuring aspects of learning with great detail, accuracy and authenticity. Moreover, they enable researchers to study how and under which conditions learning in the health care setting occurs and in which way learning can be promoted. Hence, quantitative diary methods may contribute to theory development and the optimization of teaching methods in medical education.

  10. Development of a liquid chromatography tandem mass spectrometry method for iothalamate measurement to assess renal function for potential kidney donation.

    Science.gov (United States)

    Rhea, Jeanne M; Ritchie, James C; Molinaro, Ross J

    2013-05-01

    Chronic kidney disease often goes undetected due to the insensitivity of current methods to accurately assess glomerular filtration rate (GFR) in early stages of renal dysfunction. The clearance of exogenously introduced iothalamate, a commonly used radiopaque agent, is an alternative to inulin clearance for the assessment of renal function and its use in calculating GFR can serve as a screening tool for kidney transplant donors. A method was developed to measure iothalamate in plasma and urine samples by HPLC combined with electrospray positive ionization tandem mass spectrometry (MS/MS). Iothalamate is isolated from plasma by methanol extraction and urine using a quick-spin filtration approach, then monitored by multiple reaction monitoring using the hydrogen adduct mass transitions. Iohexol was used as an internal standard. Iothalamate was measured within an analytical run time of 5 min, with a lower limit of quantification of 18.75 ng/ml. The intraassay and interassay variations of the plasma and urine iothalamate assays were both calculated using the patient's urine flow rate and plasma and urine iothalamate values. Linear correlations tested by LC-MS/MS and an accepted capillary electrophoresis (CE) assay showed similar results (GFR, r=0.92, Sy/x=10.3). We developed and validated an LC-MS/MS method for quantitating iothalamate in plasma and urine to calculate GFR used for screening potential kidney donors in our hospital system. A less sensitive mass spectrometry system does not sacrifice analytical or clinical sensitivity for measuring GFR. Copyright © 2012 Elsevier B.V. All rights reserved.

  11. Theoretical validation of potential habitability via analytical and boosted tree methods: An optimistic study on recently discovered exoplanets

    Science.gov (United States)

    Saha, S.; Basak, S.; Safonova, M.; Bora, K.; Agrawal, S.; Sarkar, P.; Murthy, J.

    2018-04-01

    Seven Earth-sized planets, known as the TRAPPIST-1 system, was discovered with great fanfare in the last week of February 2017. Three of these planets are in the habitable zone of their star, making them potentially habitable planets (PHPs) a mere 40 light years away. The discovery of the closest potentially habitable planet to us just a year before - Proxima b and a realization that Earth-type planets in circumstellar habitable zones are a common occurrence provides the impetus to the existing pursuit for life outside the Solar System. The search for life has two goals essentially: looking for planets with Earth-like conditions (Earth similarity) and looking for the possibility of life in some form (habitability). An index was recently developed, the Cobb-Douglas Habitability Score (CDHS), based on Cobb-Douglas habitability production function (CD-HPF), which computes the habitability score by using measured and estimated planetary parameters. As an initial set, radius, density, escape velocity and surface temperature of a planet were used. The proposed metric, with exponents accounting for metric elasticity, is endowed with analytical properties that ensure global optima and can be scaled to accommodate a finite number of input parameters. We show here that the model is elastic, and the conditions on elasticity to ensure global maxima can scale as the number of predictor parameters increase. K-NN (K-Nearest Neighbor) classification algorithm, embellished with probabilistic herding and thresholding restriction, utilizes CDHS scores and labels exoplanets into appropriate classes via feature-learning methods yielding granular clusters of habitability. The algorithm works on top of a decision-theoretical model using the power of convex optimization and machine learning. The goal is to characterize the recently discovered exoplanets into an "Earth League" and several other classes based on their CDHS values. A second approach, based on a novel feature-learning and

  12. 2D Stabilised analytic signal method in DC pole-pole potential data ...

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    synthetic error prone secondary pole-pole potential data. 1. Introduction. Analytical signal .... The meaning of the rest of the parameters is self- evident. The three ..... interpretation using 3-D analytic signal; Geophysics 57. 116–125. Starostenko ...

  13. Characterizing the surface charge of synthetic nanomembranes by the streaming potential method

    OpenAIRE

    Datta, Subhra; Conlisk, A. T.; Kanani, Dharmesh M.; Zydney, Andrew L.; Fissell, William H.; Roy, Shuvo

    2010-01-01

    The inference of the surface charge of polyethylene glycol (PEG)-coated and uncoated silicon membranes with nanoscale pore sizes from streaming potential measurements in the presence of finite electric double layer (EDL) effects is studied theoretically and experimentally. The developed theoretical model for inferring the pore wall surface charge density from streaming potential measurements is applicable to arbitrary pore cross-sectional shapes and accounts for the effect of finite salt conc...

  14. Novel recurrent chromosomal aberrations detected in clonal plasma cells of light chain amyloidosis patients show potential adverse prognostic effect: first results from a genome-wide copy number array analysis.

    Science.gov (United States)

    Granzow, Martin; Hegenbart, Ute; Hinderhofer, Katrin; Hose, Dirk; Seckinger, Anja; Bochtler, Tilmann; Hemminki, Kari; Goldschmidt, Hartmut; Schönland, Stefan O; Jauch, Anna

    2017-07-01

    Immunoglobulin light chain (AL) amyloidosis is a rare plasma cell dyscrasia characterized by the deposition of abnormal amyloid fibrils in multiple organs, thus impairing their function. In the largest cohort studied up to now of 118 CD138-purified plasma cell samples from previously untreated immunoglobulin light chain amyloidosis patients, we assessed in parallel copy number alterations using high-density copy number arrays and interphase fluorescence in situ hybridization (iFISH). We used fluorescence in situ hybridization probes for the IgH translocations t(11;14), t(4;14), and t(14;16) or any other IgH rearrangement as well as numerical aberrations of the chromosome loci 1q21, 8p21, 5p15/5q35, 11q22.3 or 11q23, 13q14, 15q22, 17p13, and 19q13. Recurrent gains included chromosomes 1q (36%), 9 (24%), 11q (24%), as well as 19 (15%). Recurrent losses affected chromosome 13 (29% monosomy) and partial losses of 14q (19%), 16q (14%) and 13q (12%), respectively. In 88% of patients with translocation t(11;14), the hallmark chromosomal aberration in AL amyloidosis, a concomitant gain of 11q22.3/11q23 detected by iFISH was part of the unbalanced translocation der(14)t(11;14)(q13;q32) with the breakpoint in the CCND1/MYEOV gene region. Partial loss of chromosome regions 14q and 16q were significantly associated to gain 1q. Gain 1q21 detected by iFISH almost always resulted from a gain of the long arm of chromosome 1 and not from trisomy 1, whereas deletions on chromosome 1p were rarely found. Overall and event-free survival analysis found a potential adverse prognostic effect of concomitant gain 1q and deletion 14q as well as of deletion 1p. In conclusion, in the first whole genome report of clonal plasma cells in AL amyloidosis, novel aberrations and hitherto unknown potential adverse prognostic effects were uncovered. Copyright© 2017 Ferrata Storti Foundation.

  15. Nonlinear response time-dependent density functional theory combined with the effective fragment potential method

    Energy Technology Data Exchange (ETDEWEB)

    Zahariev, Federico; Gordon, Mark S., E-mail: mark@si.msg.chem.iastate.edu [Department of Chemistry, Iowa State University, Ames, Iowa 50011 (United States)

    2014-05-14

    This work presents an extension of the linear response TDDFT/EFP method to the nonlinear-response regime together with the implementation of nonlinear-response TDDFT/EFP in the quantum-chemistry computer package GAMESS. Included in the new method is the ability to calculate the two-photon absorption cross section and to incorporate solvent effects via the EFP method. The nonlinear-response TDDFT/EFP method is able to make correct qualitative predictions for both gas phase values and aqueous solvent shifts of several important nonlinear properties.

  16. Development of a fluorescent antibody method for the detection of Enterococcus faecium and its potential for coastal aquatic environment monitoring.

    Science.gov (United States)

    Caruso, Gabriella; Monticelli, L S; Caruso, R; Bergamasco, A

    2008-02-01

    A direct, microscopic fluorescent antibody method was developed to detect the occurrence of Enterococcus faecium in coastal aquatic environments and was compared with the conventional membrane filtering method. The "in situ" application of the antibody-based protocol in the analysis of water samples collected from coastal polyhaline habitats demonstrated good sensitivity and ease of implementation. Data obtained with the microscopic technique were in agreement with those obtained from culture counts. The fluorescent antibody method proved to be a rapid and reliable technique for the detection of E. faecium. The advantages and limitations intrinsic to the method are discussed, highlighting the potential of this new technique for monitoring coastal aquatic environments.

  17. Optimization and scale up of microfluidic nanolipomer production method for preclinical and potential clinical trials.

    Science.gov (United States)

    Gdowski, Andrew; Johnson, Kaitlyn; Shah, Sunil; Gryczynski, Ignacy; Vishwanatha, Jamboor; Ranjan, Amalendu

    2018-02-12

    The process of optimization and fabrication of nanoparticle synthesis for preclinical studies can be challenging and time consuming. Traditional small scale laboratory synthesis techniques suffer from batch to batch variability. Additionally, the parameters used in the original formulation must be re-optimized due to differences in fabrication techniques for clinical production. Several low flow microfluidic synthesis processes have been reported in recent years for developing nanoparticles that are a hybrid between polymeric nanoparticles and liposomes. However, use of high flow microfluidic synthetic techniques has not been described for this type of nanoparticle system, which we will term as nanolipomer. In this manuscript, we describe the successful optimization and functional assessment of nanolipomers fabricated using a microfluidic synthesis method under high flow parameters. The optimal total flow rate for synthesis of these nanolipomers was found to be 12 ml/min and flow rate ratio 1:1 (organic phase: aqueous phase). The PLGA polymer concentration of 10 mg/ml and a DSPE-PEG lipid concentration of 10% w/v provided optimal size, PDI and stability. Drug loading and encapsulation of a representative hydrophobic small molecule drug, curcumin, was optimized and found that high encapsulation efficiency of 58.8% and drug loading of 4.4% was achieved at 7.5% w/w initial concentration of curcumin/PLGA polymer. The final size and polydispersity index of the optimized nanolipomer was 102.11 nm and 0.126, respectively. Functional assessment of uptake of the nanolipomers in C4-2B prostate cancer cells showed uptake at 1 h and increased uptake at 24 h. The nanolipomer was more effective in the cell viability assay compared to free drug. Finally, assessment of in vivo retention in mice of these nanolipomers revealed retention for up to 2 h and were completely cleared at 24 h. In this study, we have demonstrated that a nanolipomer formulation can be successfully

  18. Measurement of compartment elasticity using pressure related ultrasound: a method to identify patients with potential compartment syndrome.

    Science.gov (United States)

    Sellei, R M; Hingmann, S J; Kobbe, P; Weber, C; Grice, J E; Zimmerman, F; Jeromin, S; Gansslen, A; Hildebrand, F; Pape, H C

    2015-01-01

    PURPOSE OF THE STUDY Decision-making in treatment of an acute compartment syndrome is based on clinical assessment, supported by invasive monitoring. Thus, evolving compartment syndrome may require repeated pressure measurements. In suspected cases of potential compartment syndromes clinical assessment alone seems to be unreliable. The objective of this study was to investigate the feasibility of a non-invasive application estimating whole compartmental elasticity by ultrasound, which may improve accuracy of diagnostics. MATERIAL AND METHODS In an in-vitro model, using an artificial container simulating dimensions of the human anterior tibial compartment, intracompartmental pressures (p) were raised subsequently up to 80 mm Hg by infusion of saline solution. The compartmental depth (mm) in the cross-section view was measured before and after manual probe compression (100 mm Hg) upon the surface resulting in a linear compartmental displacement (Δd). This was repeated at rising compartmental pressures. The resulting displacements were related to the corresponding intra-compartmental pressures simulated in our model. A hypothesized relationship between pressures related compartmental displacement and the elasticity at elevated compartment pressures was investigated. RESULTS With rising compartmental pressures, a non-linear, reciprocal proportional relation between the displacement (mm) and the intra-compartmental pressure (mm Hg) occurred. The Pearson's coefficient showed a high correlation (r2 = -0.960). The intraobserver reliability value kappa resulted in a statistically high reliability (κ = 0.840). The inter-observer value indicated a fair reliability (κ = 0.640). CONCLUSIONS Our model reveals that a strong correlation between compartmental strain displacements assessed by ultrasound and the intra-compartmental pressure changes occurs. Further studies are required to prove whether this assessment is transferable to human muscle tissue. Determining the complete

  19. Exploring the potential of the drawing intervention method for design and evaluation by young children

    NARCIS (Netherlands)

    Barendregt, W.; Bekker, M.M.

    2013-01-01

    This paper describes the preliminary results of an exploratory study on the use of the Drawing Intervention method for both design and evaluation activities with young children (4-7). In this study we wanted to a) investigate how a variant of this method can be used to evaluate a game with younger

  20. Influence of adsorption and deproteination on potential free thyroxine reference methods

    DEFF Research Database (Denmark)

    Holm, Steen S; Andreasen, Lisbeth; Hansen, Palle Steen

    2002-01-01

    There is a need for consensus concerning reference methods to be used for calibration of commercial free-thyroxine (FT(4)) assays.......There is a need for consensus concerning reference methods to be used for calibration of commercial free-thyroxine (FT(4)) assays....

  1. Studying learning in the healthcare setting: the potential of quantitative diary methods

    NARCIS (Netherlands)

    Ciere, Yvette; Jaarsma, Debbie; Visser, Annemieke; Sanderman, Robbert; Snippe, Evelien; Fleer, Joke

    2015-01-01

    Quantitative diary methods are longitudinal approaches that involve the repeated measurement of aspects of peoples’ experience of daily life. In this article, we outline the main characteristics and applications of quantitative diary methods and discuss how their use may further research in the

  2. In situ performance and potential applications of a thermal bed-load measurement method

    CSIR Research Space (South Africa)

    Ilgner, HJ

    2010-09-01

    Full Text Available Methods to detect the flow condition at the pipeline invert are reviewed. New results of a small heated plate inserted into a non-metallic pipe are presented. This thermal method is based on mini-heaters and can detect erratic flow behaviour near...

  3. Recording strategies and selection potential of feed intake measured using the X-ray method in rainbow trout

    Directory of Open Access Journals (Sweden)

    Mäntysaari Esa A

    2006-06-01

    Full Text Available Abstract This study examines the way long-term feed intake should be recorded accurately for selective breeding purposes, and estimates selection potential in feed intake using the X-ray method to record individual daily feed intake in rainbow trout (Oncorhynchus mykiss. The analysis showed that the point estimates of daily feed intake displayed low repeatabilities (r = 0.09–0.32. This indicates that a minimum of three repeated records were needed to accurately record average feed intake at a fixed age. To effectively breed for feed intake over the whole growing period, it is necessary to determine average feed intake at different ages, since there were only moderate phenotypic and genetic correlations between average daily feed intake recorded at 140 g, 750 g and 2000 g wet mass. Heritability for average daily feed intake was low (average h2 = 0.10, indicating that modest genetic changes can be obtained in response to selection. It was concluded that selection to genetically change long-term feed intake can be successful, yet repeated observations at several life stages are needed to ensure the accuracy of feed intake estimates and the efficiency of selection.

  4. Automated Analysis of Facial Cues from Videos as a Potential Method for Differentiating Stress and Boredom of Players in Games

    Directory of Open Access Journals (Sweden)

    Fernando Bevilacqua

    2018-01-01

    Full Text Available Facial analysis is a promising approach to detect emotions of players unobtrusively; however approaches are commonly evaluated in contexts not related to games or facial cues are derived from models not designed for analysis of emotions during interactions with games. We present a method for automated analysis of facial cues from videos as a potential tool for detecting stress and boredom of players behaving naturally while playing games. Computer vision is used to automatically and unobtrusively extract 7 facial features aimed at detecting the activity of a set of facial muscles. Features are mainly based on the Euclidean distance of facial landmarks and do not rely on predefined facial expressions, training of a model, or the use of facial standards. An empirical evaluation was conducted on video recordings of an experiment involving games as emotion elicitation sources. Results show statistically significant differences in the values of facial features during boring and stressful periods of gameplay for 5 of the 7 features. We believe our approach is more user-tailored, convenient, and better suited for contexts involving games.

  5. The method of effective potentials in the quantum-statistical theory of plasmas

    International Nuclear Information System (INIS)

    Ebeling, W; Filinov, A; Bonitz, M; Filinov, V; Pohl, T

    2006-01-01

    We provide a survey of the concept and several successful applications of effective potentials. After introducing Kelbg's expression we discuss several useful approximations and additional generalizations including non-diagonal expressions. Finally, we present the recent results concerning non-diagonal contributions and the relation to effective interactions arising from the dynamics of Gaussian wave packets

  6. Transmembrane Potential Modeling: Comparison between Methods of Constant Electric Field and Ion Imbalance

    Czech Academy of Sciences Publication Activity Database

    Melcr, Josef; Bonhenry, Daniel; Timr, Štěpán; Jungwirth, Pavel

    2016-01-01

    Roč. 12, č. 5 (2016), s. 2418-2425 ISSN 1549-9618 R&D Projects: GA ČR(CZ) GBP208/12/G016 Institutional support: RVO:61388963 Keywords : membrane potential * molecular dynamics * ion imbalance Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 5.245, year: 2016

  7. A comparison of six potential evapotranspiration methods for regional use in the Southeastern United States

    Science.gov (United States)

    Jianbiao Lu; Ge Sun; Steven G. McNulty; Devendra Amatya

    2005-01-01

    Potential evapotranspiration (PET) is an important index of hydrologic budgets at different spatial scales and is a critical variable for understanding regional biological processes. It is often an important variable in estimating actual evapotranspiration (AET) in rainfall-runoff and ecosystem modeling. However, PET is defined in different ways in the literature and...

  8. Modified-surface-energy methods for deriving heavy-ion potentials

    International Nuclear Information System (INIS)

    Sierk, A.J.

    1977-01-01

    The use of a modified-surface-energy approach for the calculation of heavy-ion interaction potentials is discussed. It is not possible to simultaneously fit elastic scattering, ion interaction barriers, and fission barriers with the same set of constants in this model. Possible explanations of this deficiency are discussed

  9. Rapid Methods to Estimate Potential Exposure to Semivolatile Organic Compounds in the Indoor Environment

    DEFF Research Database (Denmark)

    Little, John C.; Weschler, Charles J.; Nazaroff, William W

    2012-01-01

    A systematic and efficient strategy is needed to assess and manage potential risks to human health that arise from the manufacture and use of thousands of chemicals. Among available tools for rapid assessment of large numbers of chemicals, significant gaps are associated with the capability...

  10. Characterization of Bacterial Hydrocarbon Degradation Potential in the Red Sea Through Metagenomic and Cultivation Methods

    KAUST Repository

    Bianchi, Patrick

    2018-02-01

    Prokaryotes are the main actors in biogeochemical cycles that are fundamental in global nutrient cycling. The characterization of microbial communities and isolates can enhance the comprehension of such cycles. Potentially novel biochemical processes can be discovered in particular environments with unique characteristics. The Red Sea can be considered as a unique natural laboratory due to its peculiar hydrology and physical features including temperature, salinity and water circulation. Moreover the Red Sea is subjected to hydrocarbon pollution by both anthropogenic and natural sources that select hydrocarbon degrading prokaryotes. Due to its unique features the Red Sea has the potential to host uncharacterized novel microorganisms with hydrocarbondegrading pathways. The focus of this thesis is on the characterization at the metagenomic level of the water column of the Red Sea and on the isolation and characterization of novel hydrocarbon-degrading species and genomes adapted to the unique environmental characteristics of the basin. The presence of metabolic genes responsible of both linear and aromatic hydrocarbon degradation has been evaluated from a metagenomic survey and a meta-analysis of already available datasets. In parallel, water column-based microcosms have been established with crude oil as the sole carbon source, with aim to isolate potential novel bacterial species and provide new genome-based insights on the hydrocarbon degradation potential available in the Red Sea.

  11. Geophysical methods for fracture characterization in and around potential sites for nuclear waste disposal

    International Nuclear Information System (INIS)

    Majer, E.L.; Lee, K.H.; Morrison, H.F.

    1992-08-01

    Historically, geophysical methods have been used extensively to successfully explore the subsurface for petroleum, gas, mineral, and geothermal resources. Their application, however, for site characterization, and monitoring the performance of near surface waste sites or repositories has been somewhat limited. Presented here is an overview of the geophysical methods that could contribute to defining the subsurface heterogeneity and extrapolating point measurements at the surface and in boreholes to volumetric descriptions in a fractured rock. In addition to site characterization a significant application of geophysical methods may be in performance assessment and in monitoring the repository to determine if the performance is as expected

  12. On-orbit assembly of a team of flexible spacecraft using potential field based method

    Science.gov (United States)

    Chen, Ti; Wen, Hao; Hu, Haiyan; Jin, Dongping

    2017-04-01

    In this paper, a novel control strategy is developed based on artificial potential field for the on-orbit autonomous assembly of four flexible spacecraft without inter-member collision. Each flexible spacecraft is simplified as a hub-beam model with truncated beam modes in the floating frame of reference and the communication graph among the four spacecraft is assumed to be a ring topology. The four spacecraft are driven to a pre-assembly configuration first and then to the assembly configuration. In order to design the artificial potential field for the first step, each spacecraft is outlined by an ellipse and a virtual leader of circle is introduced. The potential field mainly depends on the attitude error between the flexible spacecraft and its neighbor, the radial Euclidian distance between the ellipse and the circle and the classical Euclidian distance between the centers of the ellipse and the circle. It can be demonstrated that there are no local minima for the potential function and the global minimum is zero. If the function is equal to zero, the solution is not a certain state, but a set. All the states in the set are corresponding to the desired configurations. The Lyapunov analysis guarantees that the four spacecraft asymptotically converge to the target configuration. Moreover, the other potential field is also included to avoid the inter-member collision. In the control design of the second step, only small modification is made for the controller in the first step. Finally, the successful application of the proposed control law to the assembly mission is verified by two case studies.

  13. Calculations of wavefunctions and energies of electron system in Coulomb potential by variational method without a basis set

    International Nuclear Information System (INIS)

    Bykov, V.P.; Gerasimov, A.V.

    1992-08-01

    A new variational method without a basis set for calculation of the eigenvalues and eigenfunctions of Hamiltonians is suggested. The expansion of this method for the Coulomb potentials is given. Calculation of the energy and charge distribution in the two-electron system for different values of the nuclear charge Z is made. It is shown that at small Z the Coulomb forces disintegrate the electron cloud into two clots. (author). 3 refs, 4 figs, 1 tab

  14. Provincial carbon intensity abatement potential estimation in China: A PSO–GA-optimized multi-factor environmental learning curve method

    International Nuclear Information System (INIS)

    Yu, Shiwei; Zhang, Junjie; Zheng, Shuhong; Sun, Han

    2015-01-01

    This study aims to estimate carbon intensity abatement potential in China at the regional level by proposing a particle swarm optimization–genetic algorithm (PSO–GA) multivariate environmental learning curve estimation method. The model uses two independent variables, namely, per capita gross domestic product (GDP) and the proportion of the tertiary industry in GDP, to construct carbon intensity learning curves (CILCs), i.e., CO 2 emissions per unit of GDP, of 30 provinces in China. Instead of the traditional ordinary least squares (OLS) method, a PSO–GA intelligent optimization algorithm is used to optimize the coefficients of a learning curve. The carbon intensity abatement potentials of the 30 Chinese provinces are estimated via PSO–GA under the business-as-usual scenario. The estimation reveals the following results. (1) For most provinces, the abatement potentials from improving a unit of the proportion of the tertiary industry in GDP are higher than the potentials from raising a unit of per capita GDP. (2) The average potential of the 30 provinces in 2020 will be 37.6% based on the emission's level of 2005. The potentials of Jiangsu, Tianjin, Shandong, Beijing, and Heilongjiang are over 60%. Ningxia is the only province without intensity abatement potential. (3) The total carbon intensity in China weighted by the GDP shares of the 30 provinces will decline by 39.4% in 2020 compared with that in 2005. This intensity cannot achieve the 40%–45% carbon intensity reduction target set by the Chinese government. Additional mitigation policies should be developed to uncover the potentials of Ningxia and Inner Mongolia. In addition, the simulation accuracy of the CILCs optimized by PSO–GA is higher than that of the CILCs optimized by the traditional OLS method. - Highlights: • A PSO–GA-optimized multi-factor environmental learning curve method is proposed. • The carbon intensity abatement potentials of the 30 Chinese provinces are estimated by

  15. Synthetic Methods and Exploring Biological Potential of Various Substituted Quinoxalin-2-one Derivatives

    OpenAIRE

    Mohammad Asif

    2016-01-01

    Substituted quinoxaline have considerable interest in chemistry, biology and pharmacology. Quinoxaline derivatives are capable with variety of biological activities and possess different biological activities, of which the most potent are anti-microbial, analgesic and anti-inflammatory activities. It facilitated the researchers to develop various methods for their synthesis and their applications. In this review represented different methods of synthesis, reactivity and various biological act...

  16. Recent developments in the use of temperature, resistivity and self-potential methods for monitoring embankment dam performance

    Energy Technology Data Exchange (ETDEWEB)

    Sheffer, M.R. [BC Hydro, Vancouver, BC (Canada); Johansson, S.; Sjodahl, P. [HydroResearch AB, Taby (Sweden)

    2009-07-01

    Significant research is being undertaken in the application and development of non-intrusive geophysical techniques as a result of the need for more comprehensive surveillance to detect internal erosion in embankment dams. Seepage and piezometric measurements are the most common methods utilized for dam surveillance. However, the spatial resolution of these measurements is generally not refined enough to detect small, local seepage changes. This paper summarized the current state of the art in the application of temperature, electrical resistivity and self-potential methods to seepage monitoring at embankment dam sites. The paper presented recent developments in using the technique and interpreting seepage parameters for each method. The methods were discussed in the context of both investigation and monitoring applications. It was concluded that the resistivity method is a non-destructive method that is well suited to long-term monitoring and has the ability to cover the entire dam. 25 refs., 11 figs.

  17. A Highly Accurate Regular Domain Collocation Method for Solving Potential Problems in the Irregular Doubly Connected Domains

    Directory of Open Access Journals (Sweden)

    Zhao-Qing Wang

    2014-01-01

    Full Text Available Embedding the irregular doubly connected domain into an annular regular region, the unknown functions can be approximated by the barycentric Lagrange interpolation in the regular region. A highly accurate regular domain collocation method is proposed for solving potential problems on the irregular doubly connected domain in polar coordinate system. The formulations of regular domain collocation method are constructed by using barycentric Lagrange interpolation collocation method on the regular domain in polar coordinate system. The boundary conditions are discretized by barycentric Lagrange interpolation within the regular domain. An additional method is used to impose the boundary conditions. The least square method can be used to solve the overconstrained equations. The function values of points in the irregular doubly connected domain can be calculated by barycentric Lagrange interpolation within the regular domain. Some numerical examples demonstrate the effectiveness and accuracy of the presented method.

  18. Characterization of Bacterial Hydrocarbon Degradation Potential in the Red Sea Through Metagenomic and Cultivation Methods

    KAUST Repository

    Bianchi, Patrick

    2018-01-01

    The focus of this thesis is on the characterization at the metagenomic level of the water column of the Red Sea and on the isolation and characterization of novel hydrocarbon-degrading species and genomes adapted to the unique environmental characteristics of the basin. The presence of metabolic genes responsible of both linear and aromatic hydrocarbon degradation has been evaluated from a metagenomic survey and a meta-analysis of already available datasets. In parallel, water column-based microcosms have been established with crude oil as the sole carbon source, with aim to isolate potential novel bacterial species and provide new genome-based insights on the hydrocarbon degradation potential available in the Red Sea.

  19. A Parallel Reaction Monitoring Mass Spectrometric Method for Analysis of Potential CSF Biomarkers for Alzheimer's Disease

    DEFF Research Database (Denmark)

    Brinkmalm, Gunnar; Sjödin, Simon; Simonsen, Anja Hviid

    2018-01-01

    SCOPE: The aim of this study was to develop and evaluate a parallel reaction monitoring mass spectrometry (PRM-MS) assay consisting of a panel of potential protein biomarkers in cerebrospinal fluid (CSF). EXPERIMENTAL DESIGN: Thirteen proteins were selected based on their association with neurode......SCOPE: The aim of this study was to develop and evaluate a parallel reaction monitoring mass spectrometry (PRM-MS) assay consisting of a panel of potential protein biomarkers in cerebrospinal fluid (CSF). EXPERIMENTAL DESIGN: Thirteen proteins were selected based on their association...... with neurodegenerative diseases and involvement in synaptic function, secretory vesicle function, or innate immune system. CSF samples were digested and two to three peptides per protein were quantified using stable isotope-labeled peptide standards. RESULTS: Coefficients of variation were generally below 15%. Clinical...

  20. Determination of the maximum-depth to potential field sources by a maximum structural index method

    Science.gov (United States)

    Fedi, M.; Florio, G.

    2013-01-01

    A simple and fast determination of the limiting depth to the sources may represent a significant help to the data interpretation. To this end we explore the possibility of determining those source parameters shared by all the classes of models fitting the data. One approach is to determine the maximum depth-to-source compatible with the measured data, by using for example the well-known Bott-Smith rules. These rules involve only the knowledge of the field and its horizontal gradient maxima, and are independent from the density contrast. Thanks to the direct relationship between structural index and depth to sources we work out a simple and fast strategy to obtain the maximum depth by using the semi-automated methods, such as Euler deconvolution or depth-from-extreme-points method (DEXP). The proposed method consists in estimating the maximum depth as the one obtained for the highest allowable value of the structural index (Nmax). Nmax may be easily determined, since it depends only on the dimensionality of the problem (2D/3D) and on the nature of the analyzed field (e.g., gravity field or magnetic field). We tested our approach on synthetic models against the results obtained by the classical Bott-Smith formulas and the results are in fact very similar, confirming the validity of this method. However, while Bott-Smith formulas are restricted to the gravity field only, our method is applicable also to the magnetic field and to any derivative of the gravity and magnetic field. Our method yields a useful criterion to assess the source model based on the (∂f/∂x)max/fmax ratio. The usefulness of the method in real cases is demonstrated for a salt wall in the Mississippi basin, where the estimation of the maximum depth agrees with the seismic information.

  1. Methods of simulating low redox potential (Eh) for a basalt repository

    International Nuclear Information System (INIS)

    Jantzen, C.M.

    1983-01-01

    Basalt groundwaters have inherently low redox potentials, approximately -0.4V, which can be measured with platinum electrodes, but are difficult to reproduce during leaching experiments. In the presence of deionized water, crushed basalt reaches the measured Eh-pH values of a basalt repository. Other waste package components, such as iron, will interact with groundwater in different ways under oxic or anoxic conditions since the presence of any redox active solid will affect the groundwater Eh. 26 references, 4 figures

  2. An improved potential drop method for measuring and monitoring defects in structures

    International Nuclear Information System (INIS)

    Oppermann, W.; Keller, H.P.

    1991-01-01

    In its advanced form, the direct-current potential probe measuring technique is a reliable and relatively exact procedure for measuring and monitoring surface defects. In addition, there is the possibility - important for practical purposes - of measuring cracks at the inaccessible side of a component part. The improved accuracy, in particular with regard to short defects, is based on advanced measuring techniques and calibration curves determined at the electrolytical tank. (orig./DG) [de

  3. Molecular Methods Used for the Identification of Potentially Probiotic Lactobacillus reuteri Strains

    OpenAIRE

    Weiss, Agnes; Lettner, Hans Peter; Kramer, Walter; Mayer, Helmut Karl; Kneifel, Wolfgang

    2005-01-01

    Forty potentially probiotic Lactobacillus strains as well as reference strains of different genera were grown under standardised conditions. Cell masses were harvested and DNA was isolated. For identification, all strains were subjected to genus-specific polymerase chain reaction (PCR), and the affiliation with the genus Lactobacillus was confirmed for all isolates. Using two species-specific primer-pairs for Lactobacillus reuteri, specific amplicons were observed for eight of the forty inves...

  4. The computation of ionization potentials for second-row elements by ab initio and density functional theory methods

    International Nuclear Information System (INIS)

    Jursic, B.S.

    1996-01-01

    Up to four ionization potentials of elements from the second-row of the periodic table were computed using the ab initio (HF, MP2, MP3, MP4, QCISD, GI, G2, and G2MP2) and DFT (B3LY, B3P86, B3PW91, XALPHA, HFS, HFB, BLYP, BP86, BPW91, BVWN, XAPLY, XAP86, XAPW91, XAVWN, SLYR SP86, SPW91 and SVWN) methods. In all of the calculations, the large 6-311++G(3df,3pd) gaussian type of basis set was used. The computed values were compared with the experimental results and suitability of the ab initio and DFF methods were discussed, in regard to reproducing the experimental data. From the computed ionization potentials of the second-row elements, it can be concluded that the HF ab initio computation is not capable of reproducing the experimental results. The computed ionization potentials are too low. However, by using the ab initio methods that include electron correlation, the computed IPs are becoming much closer to the experimental values. In all cases, with the exception of the first ionization potential for oxygen, the G2 computation result produces ionization potentials that are indistinguishable from the experimental results

  5. The Potential Application of Qualitative Evaluation Methods in European Regional Development : Reflections on the Use of Performance Story Reporting in Australian Natural Resource Management

    NARCIS (Netherlands)

    Vanclay, Frank

    2015-01-01

    Vanclay F. The potential application of qualitative evaluation methods in European regional development: reflections on the use of Performance Story Reporting in Australian natural resource management, Regional Studies. This paper argues that qualitative evaluation methods potentially have a useful

  6. The potentialities of nuclear geophysical methods in ore testing of ferrous metals

    International Nuclear Information System (INIS)

    Ochkur, A.P.; Voznesenskij, L.I.; Fedorov, S.V.

    1976-01-01

    To study iron ores of simple composition, the gamma-gamma method is used successfully, determining iron contents in boreholes, in the walls of mine workings and in sampling hacked off rocks. The X-ray diffraction method is used effectively in analysing iron ores of complex composition ensuring that the contents of Fe, Mn and Ca are determined in them. Neutron-capture spectrometric gamma-logging is a promising method for determining the total iron content in the mined ore. Manganese ores are singled out in the boreholes by data from thermal neutron and neutron-activation logging. The X-ray diffraction method is used to analyse powder samples in mine workings. To single out and estimate chromites in boreholes, a combination of neutron-capture spectrometric gamma-logging, gamma-gamma logging and epithermal neutron-neutron logging is used. The X-ray diffraction method determines the contents of Cr, Ca and Fe in powder and coarse-ground samples of chromites

  7. On the potential of computational methods and numerical simulation in ice mechanics

    International Nuclear Information System (INIS)

    Bergan, Paal G; Cammaert, Gus; Skeie, Geir; Tharigopula, Venkatapathi

    2010-01-01

    This paper deals with the challenge of developing better methods and tools for analysing interaction between sea ice and structures and, in particular, to be able to calculate ice loads on these structures. Ice loads have traditionally been estimated using empirical data and 'engineering judgment'. However, it is believed that computational mechanics and advanced computer simulations of ice-structure interaction can play an important role in developing safer and more efficient structures, especially for irregular structural configurations. The paper explains the complexity of ice as a material in computational mechanics terms. Some key words here are large displacements and deformations, multi-body contact mechanics, instabilities, multi-phase materials, inelasticity, time dependency and creep, thermal effects, fracture and crushing, and multi-scale effects. The paper points towards the use of advanced methods like ALE formulations, mesh-less methods, particle methods, XFEM, and multi-domain formulations in order to deal with these challenges. Some examples involving numerical simulation of interaction and loads between level sea ice and offshore structures are presented. It is concluded that computational mechanics may prove to become a very useful tool for analysing structures in ice; however, much research is still needed to achieve satisfactory reliability and versatility of these methods.

  8. Molecular wave function and effective adiabatic potentials calculated by extended multi-configuration time-dependent Hartree-Fock method

    Energy Technology Data Exchange (ETDEWEB)

    Kato, Tsuyoshi; Ide, Yoshihiro; Yamanouchi, Kaoru [Department of Chemistry, School of Science, The University of Tokyo, 7-3-1, Hongo Bunkyo-ku, Tokyo, 113-0033 (Japan)

    2015-12-31

    We first calculate the ground-state molecular wave function of 1D model H{sub 2} molecule by solving the coupled equations of motion formulated in the extended multi-configuration time-dependent Hartree-Fock (MCTDHF) method by the imaginary time propagation. From the comparisons with the results obtained by the Born-Huang (BH) expansion method as well as with the exact wave function, we observe that the memory size required in the extended MCTDHF method is about two orders of magnitude smaller than in the BH expansion method to achieve the same accuracy for the total energy. Second, in order to provide a theoretical means to understand dynamical behavior of the wave function, we propose to define effective adiabatic potential functions and compare them with the conventional adiabatic electronic potentials, although the notion of the adiabatic potentials is not used in the extended MCTDHF approach. From the comparison, we conclude that by calculating the effective potentials we may be able to predict the energy differences among electronic states even for a time-dependent system, e.g., time-dependent excitation energies, which would be difficult to be estimated within the BH expansion approach.

  9. Airy function approach and Numerov method to study the anharmonic oscillator potentials V(x = Ax2α + Bx2

    Directory of Open Access Journals (Sweden)

    N. Al Sdran

    2016-06-01

    Full Text Available The numerical solutions of the time independent Schrödinger equation of different one-dimensional potentials forms are sometime achieved by the asymptotic iteration method. Its importance appears, for example, on its efficiency to describe vibrational system in quantum mechanics. In this paper, the Airy function approach and the Numerov method have been used and presented to study the oscillator anharmonic potential V(x = Ax2α + Bx2, (A>0, B<0, with (α = 2 for quadratic, (α =3 for sextic and (α =4 for octic anharmonic oscillators. The Airy function approach is based on the replacement of the real potential V(x by a piecewise-linear potential v(x, while, the Numerov method is based on the discretization of the wave function on the x-axis. The first energies levels have been calculated and the wave functions for the sextic system have been evaluated. These specific values are unlimited by the magnitude of A, B and α. It’s found that the obtained results are in good agreement with the previous results obtained by the asymptotic iteration method for α =3.

  10. Method Development and Application to Determine Potential Plant Uptake of Antibiotics and Other Drugs in Irrigated Crop Production Systems

    Science.gov (United States)

    Recent studies have shown the detection of pharmaceuticals in surface waters across the United States. The objective of this study was to develop methods, and apply them, to evaluate the potential for food chain transfer when pharmaceutical containing wastewaters are used for cr...

  11. Generalisation of the method of images for the calculation of inviscid potential flow past several arbitrarily moving parallel circular cylinders

    Czech Academy of Sciences Publication Activity Database

    Kharlamov, Alexander A.; Filip, Petr

    2012-01-01

    Roč. 77, č. 1 (2012), s. 77-85 ISSN 0022-0833 Institutional research plan: CEZ:AV0Z20600510 Keywords : circular cylinders * cylinder between two walls * generalised method of images * ideal fluid * potential flow Subject RIV: BK - Fluid Dynamics Impact factor: 1.075, year: 2012

  12. An implicit boundary integral method for computing electric potential of macromolecules in solvent

    Science.gov (United States)

    Zhong, Yimin; Ren, Kui; Tsai, Richard

    2018-04-01

    A numerical method using implicit surface representations is proposed to solve the linearized Poisson-Boltzmann equation that arises in mathematical models for the electrostatics of molecules in solvent. The proposed method uses an implicit boundary integral formulation to derive a linear system defined on Cartesian nodes in a narrowband surrounding the closed surface that separates the molecule and the solvent. The needed implicit surface is constructed from the given atomic description of the molecules, by a sequence of standard level set algorithms. A fast multipole method is applied to accelerate the solution of the linear system. A few numerical studies involving some standard test cases are presented and compared to other existing results.

  13. An Evaluation of Two Hydrograph Separation Methods of Potential Use in Regional Water Quality Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Huff, D.D.

    1999-01-01

    Streamflow data are more useful for evaluating hydrologic model results and studying water quality once baseflow and storm runoff have been separated. However, it is important to select an appropriate hydrograph separation method. They examined tow methods and evaluated their conceptual basis, ease of application, cost of data processing, and acceptability of results. they chose the quick flow hydrograph separation method, which is in use at the Coweeta Hydrologic Laboratory, because it gives acceptable results and is easy and inexpensive to use. For regional assessment, they anticipate that the Coweeta program will be useful as an aid in developing general quantitative relationships between changes in land use and the associated changes in surface runoff yield and water quality degradation.

  14. Potential of the PIGE method in the analysis of biological and mineral materials

    International Nuclear Information System (INIS)

    Havranek, V.

    2006-01-01

    A possible application of the PIGE method for the analysis of the biological and mineral samples has been tested using a 3.5 MeV Van de Graaff accelerator. The limits of detection of 4 mg/kg for fluorine, 10 mg/kg for aluminium and 200 mg/kg for phosphorus were achieved with a 3.15 MeV proton beam (8 mm in diameter, 20 nA current and 1000 s irradiation time). The PIGE method was found to be a suitable method for the determination of fluorine in the samples analyzed. With this technique, total fluorine in the sample can be quantitated without any chemical treatment. In the analysis of the phosphorus in thick biological samples, PIGE can compete with PIXE and is probably less sensitive to matrix effects and spectra fitting, which may bring about a higher accuracy of the results

  15. [Current teaching, learning and examination methods in medical education and potential applications in rehabilitative issues].

    Science.gov (United States)

    Schwarzkopf, S R; Morfeld, M; Gülich, M; Lay, W; Horn, K; Mau, W

    2007-04-01

    With introduction of the new Federal Medical Licensing Regulations (Approbationsordnung) in Germany, integrated teaching in "Rehabilitation, Physical Medicine, Naturopathic Treatment" (Querschnittsbereich Q12) has become obligatory for the first time. Furthermore, the new Regulations require the medical faculties in Germany to realize an innovative didactic orientation in teaching. This paper provides an overview of recent applications of teaching techniques and examination methods in medical education with special consideration of the new integrated course Q12 and further teaching methods related to rehabilitative issues. Problem-oriented learning (POL), problem-based learning (PBL), bedside teaching, eLearning, and the examination methods Objective Structured Clinical Examination (OSCE) and Triple Jump are in the focus. This overview is intended as the basis for subsequent publications of the Commission for Undergraduate and Postgraduate Training of the German Society of Rehabilitation Science (DGRW), which will present examples of innovative teaching material.

  16. Delta self-consistent field method to obtain potential energy surfaces of excited molecules on surfaces

    DEFF Research Database (Denmark)

    Gavnholt, Jeppe; Olsen, Thomas; Engelund, Mads

    2008-01-01

    is a density-functional method closely resembling standard density-functional theory (DFT), the only difference being that in Delta SCF one or more electrons are placed in higher lying Kohn-Sham orbitals instead of placing all electrons in the lowest possible orbitals as one does when calculating the ground......-state energy within standard DFT. We extend the Delta SCF method by allowing excited electrons to occupy orbitals which are linear combinations of Kohn-Sham orbitals. With this extra freedom it is possible to place charge locally on adsorbed molecules in the calculations, such that resonance energies can...... be estimated, which is not possible in traditional Delta SCF because of very delocalized Kohn-Sham orbitals. The method is applied to N2, CO, and NO adsorbed on different metallic surfaces and compared to ordinary Delta SCF without our modification, spatially constrained DFT, and inverse...

  17. Relativistic effect of pseudospin symmetry and tensor coupling on the Mie-type potential via Laplace transformation method

    International Nuclear Information System (INIS)

    Eshghi, M.; Ikhdair, S. M.

    2014-01-01

    A relativistic Mie-type potential for spin-1/2 particles is studied. The Dirac Hamiltonian contains a scalar S(r) and a vector V(r) Mie-type potential in the radial coordinates, as well as a tensor potential U(r) in the form of Coulomb potential. In the pseudospin (p-spin) symmetry setting Σ = C ps and Δ = V(r), an analytical solution for exact bound states of the corresponding Dirac equation is found. The eigenenergies and normalized wave functions are presented and particular cases are discussed with any arbitrary spin—orbit coupling number κ. Special attention is devoted to the case Σ = 0 for which p-spin symmetry is exact. The Laplace transform approach (LTA) is used in our calculations. Some numerical results are obtained and compared with those of other methods. (general)

  18. Introducing a new family of short-range potentials and their numerical solutions using the asymptotic iteration method

    Science.gov (United States)

    Assi, I. A.; Sous, A. J.

    2018-05-01

    The goal of this work is to derive a new class of short-range potentials that could have a wide range of physical applications, specially in molecular physics. The tridiagonal representation approach has been developed beyond its limitations to produce new potentials by requiring the representation of the Schrödinger wave operator to be multidiagonal and symmetric. This produces a family of Hulthén potentials that has a specific structure, as mentioned in the introduction. As an example, we have solved the nonrelativistic wave equation for the new four-parameter short-range screening potential numerically using the asymptotic iteration method, where we tabulated the eigenvalues for both s -wave and arbitrary l -wave cases in tables.

  19. Growing Sandalwood in Nepal—Potential silvicultural methods and research priorities

    Science.gov (United States)

    Peter E. Neil

    1990-01-01

    Interest in sandalwood has increased recently in Nepal as a result of a royal directive to plant it in the Eastern Development Region. The most suitable seed sources, seed acquisition, nursery techniques, direct sowing and plantation establishment methods are discussed here on the basis of results from elsewhere. Suggestions are made as to what research is most needed...

  20. Potential Use of Agile Methods in Selected DoD Acquisitions: Requirements Development and Management

    Science.gov (United States)

    2014-04-01

    guidelines. 9 Kanban is a technique for managing workflow originating from the lean engineering methods pioneered by Toyota. [Reinertsen 2009...Cockburn, Alistair, & Pols, Andy. Patterns for Effective Use Cas- es. Addison-Wesley, 2002. Anderson, David. Kanban . Blue Hole Press, 2010. CMU/SEI-2013

  1. A fluorescence high throughput screening method for the detection of reactive electrophiles as potential skin sensitizers

    Science.gov (United States)

    Skin sensitization is an important toxicological end-point in the risk assessment of chemical allergens. Because of the complexity of the biological mechanisms associated with skin sensitization integrated approaches combining different chemical, biological and in silico methods are recommended to r...

  2. Methods of mineral potential assessment of uranium deposits: A mineral systems approach

    International Nuclear Information System (INIS)

    Jaireth, S.

    2014-01-01

    Conclusions: • Choice of methods depends on the objective; • Basics: – Know your mineral system (deposit-type): SCIENCE; – Create useful datasets: A MUST; • Mineral system approach can be rewarding. For successful examples visit GA’s website; • Don’t overdo or oversell it (only detailed exploration such as drilling can find a deposit)

  3. A simple method for estimating potential relative radiation (PRR) for landscape-vegetation analysis.

    Science.gov (United States)

    Kenneth B. Jr. Pierce; Todd Lookingbill; Dean. Urban

    2005-01-01

    Radiation is one of the primary influences on vegetation composition and spatial pattern. Topographic orientation is often used as a proxy for relative radiation load due to its effects on evaporative demand and local temperature. Common methods for incorporating this information (i.e., site measures of slope and aspect) fail to include daily or annual changes in solar...

  4. Experience-Sampling Research Methods and Their Potential for Education Research

    Science.gov (United States)

    Zirkel, Sabrina; Garcia, Julie A.; Murphy, Mary C.

    2015-01-01

    Experience-sampling methods (ESM) enable us to learn about individuals' lives in context by measuring participants' feelings, thoughts, actions, context, and/or activities as they go about their daily lives. By capturing experience, affect, and action "in the moment" and with repeated measures, ESM approaches allow researchers…

  5. A simple method for estimating potential source term bypass fractions from confinement structures

    International Nuclear Information System (INIS)

    Kalinich, D.A.; Paddleford, D.F.

    1997-01-01

    Confinement structures house many of the operating processes at the Savannah River Site (SRS). Under normal operating conditions, a confinement structure in conjunction with its associated ventilation systems prevents the release of radiological material to the environment. However, under potential accident conditions, the performance of the ventilation systems and integrity of the structure may be challenged. In order to calculate the radiological consequences associated with a potential accident (e.g. fires, explosion, spills, etc.), it is necessary to determine the fraction of the source term initially generated by the accident that escapes from the confinement structure to the environment. While it would be desirable to estimate the potential bypass fraction using sophisticated control-volume/flow path computer codes (e.g. CONTAIN, MELCOR, etc.) in order to take as much credit as possible for the mitigative effects of the confinement structure, there are many instances where using such codes is not tractable due to limits on the level-of-effort allotted to perform the analysis. Moreover, the current review environment, with its emphasis on deterministic/bounding-versus probabilistic/best-estimate-analysis discourages using analytical techniques that require the consideration of a large number of parameters. Discussed herein is a simplified control-volume/flow path approach for calculating source term bypass fraction that is amenable to solution in a spreadsheet or with a commercial mathematical solver (e.g. MathCad or Mathematica). It considers the effects of wind and fire pressure gradients on the structure, ventilation system operation, and Halon discharges. Simple models are used to characterize the engineered and non-engineered flow paths. By making judicious choices for the limited set of problem parameters, the results from this approach can be defended as bounding and conservative

  6. Efficient and Adaptive Methods for Computing Accurate Potential Surfaces for Quantum Nuclear Effects: Applications to Hydrogen-Transfer Reactions.

    Science.gov (United States)

    DeGregorio, Nicole; Iyengar, Srinivasan S

    2018-01-09

    We present two sampling measures to gauge critical regions of potential energy surfaces. These sampling measures employ (a) the instantaneous quantum wavepacket density, an approximation to the (b) potential surface, its (c) gradients, and (d) a Shannon information theory based expression that estimates the local entropy associated with the quantum wavepacket. These four criteria together enable a directed sampling of potential surfaces that appears to correctly describe the local oscillation frequencies, or the local Nyquist frequency, of a potential surface. The sampling functions are then utilized to derive a tessellation scheme that discretizes the multidimensional space to enable efficient sampling of potential surfaces. The sampled potential surface is then combined with four different interpolation procedures, namely, (a) local Hermite curve interpolation, (b) low-pass filtered Lagrange interpolation, (c) the monomial symmetrization approximation (MSA) developed by Bowman and co-workers, and (d) a modified Shepard algorithm. The sampling procedure and the fitting schemes are used to compute (a) potential surfaces in highly anharmonic hydrogen-bonded systems and (b) study hydrogen-transfer reactions in biogenic volatile organic compounds (isoprene) where the transferring hydrogen atom is found to demonstrate critical quantum nuclear effects. In the case of isoprene, the algorithm discussed here is used to derive multidimensional potential surfaces along a hydrogen-transfer reaction path to gauge the effect of quantum-nuclear degrees of freedom on the hydrogen-transfer process. Based on the decreased computational effort, facilitated by the optimal sampling of the potential surfaces through the use of sampling functions discussed here, and the accuracy of the associated potential surfaces, we believe the method will find great utility in the study of quantum nuclear dynamics problems, of which application to hydrogen-transfer reactions and hydrogen

  7. Investigation of potential analytical methods for redox control of the vitrification process

    International Nuclear Information System (INIS)

    Goldman, D.S.

    1985-11-01

    An investigation was conducted to evaluate several analytical techniques to measure ferrous/ferric ratios in simulated and radioactive nuclear waste glasses for eventual redox control of the vitrification process. Redox control will minimize the melt foaming that occurs under highly oxidizing conditions and the metal precipitation that occurs under highly reducing conditions. The analytical method selected must have a rapid response for production problems with minimal complexity and analyst involvement. The wet-chemistry, Moessbauer spectroscopy, glass color analysis, and ion chromatography techniques were explored, with particular emphasis being placed on the Moessbauer technique. In general, all of these methods can be used for nonradioactive samples. The Moessbauer method can readily analyze glasses containing uranium and thorium. A shielded container was designed and built to analyze fully radioactive glasses with the Moessbauer spectrometer in a hot cell environment. However, analyses conducted with radioactive waste glasses containing 90 Sr and 137 Cs were unsuccessful, presumably due to background radiation problems caused by the samples. The color of glass powder can be used to analyze the ferrous/ferric ratio for low chromium glasses, but this method may not be as precise as the others. Ion chromatography was only tested on nonradioactive glasses, but this technique appears to have the required precision due to its analysis of both Fe +2 and Fe +3 and its anticipated adaptability for radioactivity samples. This development would be similar to procedures already in use for shielded inductively coupled plasma emission (ICP) spectrometry. Development of the ion chromatography method is therefore recommended; conventional wet-chemistry is recommended as a backup procedure

  8. Modeling of the Through-the-Thickness Electric Potentials of a Piezoelectric Bimorph Using the Spectral Element Method

    Directory of Open Access Journals (Sweden)

    Xingjian Dong

    2014-02-01

    Full Text Available An efficient spectral element (SE with electric potential degrees of freedom (DOF is proposed to investigate the static electromechanical responses of a piezoelectric bimorph for its actuator and sensor functions. A sublayer model based on the piecewise linear approximation for the electric potential is used to describe the nonlinear distribution of electric potential through the thickness of the piezoelectric layers. An equivalent single layer (ESL model based on first-order shear deformation theory (FSDT is used to describe the displacement field. The Legendre orthogonal polynomials of order 5 are used in the element interpolation functions. The validity and the capability of the present SE model for investigation of global and local responses of the piezoelectric bimorph are confirmed by comparing the present solutions with those obtained from coupled 3-D finite element (FE analysis. It is shown that, without introducing any higher-order electric potential assumptions, the current method can accurately describe the distribution of the electric potential across the thickness even for a rather thick bimorph. It is revealed that the effect of electric potential is significant when the bimorph is used as sensor while the effect is insignificant when the bimorph is used as actuator, and therefore, the present study may provide a better understanding of the nonlinear induced electric potential for bimorph sensor and actuator.

  9. Economics show CO2 EOR potential in central Kansas

    Science.gov (United States)

    Dubois, M.K.; Byrnes, A.P.; Pancake, R.E.; Willhite, G.P.; Schoeling, L.G.

    2000-01-01

    Carbon dioxide (CO2) enhanced oil recovery (EOR) may be the key to recovering hundreds of millions of bbl of trapped oil from the mature fields in central Kansas. Preliminary economic analysis indicates that CO2 EOR should provide an internal rate of return (IRR) greater than 20%, before income tax, assuming oil sells for \\$20/bbl, CO2 costs \\$1/Mcf, and gross utilization is 10 Mcf of CO2/bbl of oil recovered. If the CO2 cost is reduced to \\$0.75/Mcf, an oil price of $17/bbl yields an IRR of 20%. Reservoir and economic modeling indicates that IRR is most sensitive to oil price and CO2 cost. A project requires a minimum recovery of 1,500 net bbl/acre (about 1 million net bbl/1-mile section) under a best-case scenario. Less important variables to the economics are capital costs and non-CO2 related lease operating expenses.

  10. The potential of soft computing methods in NPP instrumentation and control

    International Nuclear Information System (INIS)

    Hampel, R.; Chaker, N.; Kaestner, W.; Traichel, A.; Wagenknecht, M.; Gocht, U.

    2002-01-01

    The method of signal processing by soft computing include the application of fuzzy logic, synthetic neural networks, and evolutionary algorithms. The article contains an outline of the objectives and results of the application of fuzzy logic and methods of synthetic neural networks in nuclear measurement and control. The special requirements to be met by the software in safety-related areas with respect to reliability, evaluation, and validation are described. Possible uses may be in off-line applications in modeling, simulation, and reliability analysis as well as in on-line applications (real-time systems) for instrumentation and control. Safety-related aspects of signal processing are described and analyzed for the fuzzy logic and synthetic neural network concepts. Application are covered in selected examples. (orig.)

  11. Potential of accuracy profile for method validation in inductively coupled plasma spectrochemistry

    International Nuclear Information System (INIS)

    Mermet, J.M.; Granier, G.

    2012-01-01

    Method validation is usually performed over a range of concentrations for which analytical criteria must be verified. One important criterion in quantitative analysis is accuracy, i.e. the contribution of both trueness and precision. The study of accuracy over this range is called an accuracy profile and provides experimental tolerance intervals. Comparison with acceptability limits fixed by the end user defines a validity domain. This work describes the computation involved in the building of the tolerance intervals, particularly for the intermediate precision with within-laboratory experiments and for the reproducibility with interlaboratory studies. Computation is based on ISO 5725‐4 and on previously published work. Moreover, the bias uncertainty is also computed to verify the bias contribution to accuracy. The various types of accuracy profile behavior are exemplified with results obtained by using ICP-MS and ICP-AES. This procedure allows the analyst to define unambiguously a validity domain for a given accuracy. However, because the experiments are time-consuming, the accuracy profile method is mainly dedicated to method validation. - Highlights: ► An analytical method is defined by its accuracy, i.e. both trueness and precision. ► The accuracy as a function of an analyte concentration is an accuracy profile. ► Profile basic concepts are explained for trueness and intermediate precision. ► Profile-based tolerance intervals have to be compared with acceptability limits. ► Typical accuracy profiles are given for both ICP-AES and ICP-MS techniques.

  12. METHODICAL APPROACH TO AN ASSESSMENT OF THE POTENTIAL OF THE BUSINESS MODEL OF THE ENTERPRISE

    Directory of Open Access Journals (Sweden)

    Artur D. Bobryshev

    2018-01-01

    Full Text Available Purpose: the development of a methodical approach to carrying out objective assessment of a business model of the enterprise at justifi cation of investment decisions in the industry.Methods: the study is based on the application of methods of analysis of financial state of enterprises, structural, statistical analyses, expert assessments and business modeling. Actual information about the industry obtained from the materials of the Center server corporate disclosure.Results: widely known abroad the concept of business modeling is gradually finding its deserved recognition in the preparation of investment decisions in industry. Meanwhile, up to the present time specialists are not offered objective mechanism for assessing the degree of optimality of the business model of the industrial enterprise. Judgments about the excellence or badness of a business model are made on the basis of intuitive perception of experts about the completeness of the reflection in it of the main components of modern business. However, this approach in the justification of investment in industrial enterprise entails too high a price to erroneous conclusions based on subjective perceptions. To ensure an objective assessment of excellence models, the proposed methodological rationale of this work is based on comparing the actual parameters of the business and its target the formalized values.Conclusions and Relevance: the recommended use of the mathematical apparatus of the factor analysis of the business model of the industrial enterprise makes the work to support investment decisions in a scientifically sound procedure that guarantees obtaining reliable results.

  13. Failed back surgery syndrome - the potential and role of imaging methods

    International Nuclear Information System (INIS)

    Nekula, J.; Herman, M.; Burval, S.; Vaverka, M.

    1997-01-01

    An account is presented of early and late complications after surgery of invertebral disc prolapse in the lumbar area, and the authors' experience is compared with published data. Forty percent patients after lumbar discectomy have residual complaints; identification of their causes is the objective of imaging methods. Changes in the epidural space develop after disc surgery, owing to which epidural fibrosis is found in 40% CT and 60% MR examinations of even asymptomatic patients. Although being unable to discriminate between symptomatic and asymptomatic fibrosis, current imaging methods permit discriminating between a relapse of hernia and epidural fibrosis, which is the problem the radiologist is most frequently required to solve. This is possible in CT and MR examination with intravenous administration of a contrast substance. MR is superior to CT in that this technique visualizes the spine along its whole length, in all the 3 planes, and differentiates more precisely between the soft parts. MR is also useful in the diagnosis of spondylodiscitis, although modern isotope methods are more sensitive in this respect. Arachnopathies and periradiculitis are diagnosed most precisely by myelography. (orig.). 30 figs., 16 refs

  14. Possible experiments to distinguish between different methods of treating the Pauli principle in nuclear potential models

    International Nuclear Information System (INIS)

    Krolle, D.; Assenbaum, H.J.; Funck, C.; Langanke, K.

    1987-01-01

    The finite Pauli repulsion model of Walliser and Nakaichi-Maeda and the orthogonality condition model are two microscopically motivated potential models for the description of nuclear collisions which, however, differ from each other in the way they incorporate antisymmetrization effects into the nucleus-nucleus interaction. We have used α+α scattering at low energies as a tool to distinguish between the two different treatments of the Pauli principle. Both models are consistent with the presently available on-shell (elastic) and off-shell (bremsstrahlung) data. We suggest further measurements of α+α bremsstrahlung including the coplanar laboratory differential cross section in Harvard geometry at α-particle angles of around 27 0 and the γ-decay width of the 4 + resonance at E/sub c.m./ = 11.4 MeV, because in both cases the two models make significantly different predictions

  15. Nomogram Method as Means for Resource Potential Efficiency Predicative Aid of Petrothermal Energy

    Science.gov (United States)

    Gabdrakhmanova, K. F.; Izmailova, G. R.; Larin, P. A.; Vasilyeva, E. R.; Madjidov, M. A.; Marupov, S. R.

    2018-05-01

    The article describes the innovative approach when predicting the resource potential efficiency of petrothermal energy. Various geothermal gradients representative of Bashkortostan and Tatarstan republics regions were considered. With the help of nomograms, the authors analysed fluid temperature dependency graphs at the outlet and the thermal power versus fluid velocity along the wellbore. From the family of graphs plotted by us, velocities corresponding to specific temperature were found. Then, according to thermal power versus velocity curve, power levels corresponding to these velocities relative to the selected fluid temperature were found. On the basis of two dependencies obtained, nomograms were plotted. The result of determining the petrothermal energy production efficiency is a family of isocline lines that enables one to select the optimum temperature and injection rate to obtain the required amount of heat for a particular depth and geothermal gradient.

  16. A Novel Method for Determining the Inhibitory Potential of Anti-HIV Drugs

    Science.gov (United States)

    Shen, Lin; Rabi, S. Alireza; Siliciano, Robert F.

    2009-01-01

    In the absence of a cure, most HIV-1-infected individuals will require life-long treatment. It is therefore essential to optimize highly active antiretroviral therapy. Recent research has shown that the slope parameter or Hill coefficient, which describes the steepness of a dose-response curve, is a critical missing dimension in the evaluation of antiviral drug activity. Based on this finding, the instantaneous inhibitory potential (IIP) has been derived as a new measure of antiviral drug activity. IIP incorporates the slope parameter and thus is a more accurate pharmacodynamic measure of antiviral activity than current measures such as IC50 and inhibitory quotient. However, it remains important to determine how to use IIP to predict the in vivo efficacy of anti-HIV-1 drugs. This article discusses recent advances in in vitro measures of antiviral activity and the therapeutic implications of the dose-response curve slope and IIP. PMID:19837466

  17. Combining genomic sequencing methods to explore viral diversity and reveal potential virus-host interactions

    Directory of Open Access Journals (Sweden)

    Cheryl-Emiliane Tien Chow

    2015-04-01

    Full Text Available Viral diversity and virus-host interactions in oxygen-starved regions of the ocean, also known as oxygen minimum zones (OMZs, remain relatively unexplored. Microbial community metabolism in OMZs alters nutrient and energy flow through marine food webs, resulting in biological nitrogen loss and greenhouse gas production. Thus, viruses infecting OMZ microbes have the potential to modulate community metabolism with resulting feedback on ecosystem function. Here, we describe viral communities inhabiting oxic surface (10m and oxygen-starved basin (200m waters of Saanich Inlet, a seasonally anoxic fjord on the coast of Vancouver Island, British Columbia using viral metagenomics and complete viral fosmid sequencing on samples collected between April 2007 and April 2010. Of 6459 open reading frames (ORFs predicted across all 34 viral fosmids, 77.6% (n=5010 had no homology to reference viral genomes. These fosmids recruited a higher proportion of viral metagenomic sequences from Saanich Inlet than from nearby northeastern subarctic Pacific Ocean (Line P waters, indicating differences in the viral communities between coastal and open ocean locations. While functional annotations of fosmid ORFs were limited, recruitment to NCBI’s non-redundant ‘nr’ database and publicly available single-cell genomes identified putative viruses infecting marine thaumarchaeal and SUP05 proteobacteria to provide potential host linkages with relevance to coupled biogeochemical cycling processes in OMZ waters. Taken together, these results highlight the power of coupled analyses of multiple sequence data types, such as viral metagenomic and fosmid sequence data with prokaryotic single cell genomes, to chart viral diversity, elucidate genomic and ecological contexts for previously unclassifiable viral sequences, and identify novel host interactions in natural and engineered ecosystems.

  18. An improved fast multipole method for electrostatic potential calculations in a class of coarse-grained molecular simulations

    International Nuclear Information System (INIS)

    Poursina, Mohammad; Anderson, Kurt S.

    2014-01-01

    This paper presents a novel algorithm to approximate the long-range electrostatic potential field in the Cartesian coordinates applicable to 3D coarse-grained simulations of biopolymers. In such models, coarse-grained clusters are formed via treating groups of atoms as rigid and/or flexible bodies connected together via kinematic joints. Therefore, multibody dynamic techniques are used to form and solve the equations of motion of such coarse-grained systems. In this article, the approximations for the potential fields due to the interaction between a highly negatively/positively charged pseudo-atom and charged particles, as well as the interaction between clusters of charged particles, are presented. These approximations are expressed in terms of physical and geometrical properties of the bodies such as the entire charge, the location of the center of charge, and the pseudo-inertia tensor about the center of charge of the clusters. Further, a novel substructuring scheme is introduced to implement the presented far-field potential evaluations in a binary tree framework as opposed to the existing quadtree and octree strategies of implementing fast multipole method. Using the presented Lagrangian grids, the electrostatic potential is recursively calculated via sweeping two passes: assembly and disassembly. In the assembly pass, adjacent charged bodies are combined together to form new clusters. Then, the potential field of each cluster due to its interaction with faraway resulting clusters is recursively calculated in the disassembly pass. The method is highly compatible with multibody dynamic schemes to model coarse-grained biopolymers. Since the proposed method takes advantage of constant physical and geometrical properties of rigid clusters, improvement in the overall computational cost is observed comparing to the tradition application of fast multipole method

  19. An improved fast multipole method for electrostatic potential calculations in a class of coarse-grained molecular simulations

    Science.gov (United States)

    Poursina, Mohammad; Anderson, Kurt S.

    2014-08-01

    This paper presents a novel algorithm to approximate the long-range electrostatic potential field in the Cartesian coordinates applicable to 3D coarse-grained simulations of biopolymers. In such models, coarse-grained clusters are formed via treating groups of atoms as rigid and/or flexible bodies connected together via kinematic joints. Therefore, multibody dynamic techniques are used to form and solve the equations of motion of such coarse-grained systems. In this article, the approximations for the potential fields due to the interaction between a highly negatively/positively charged pseudo-atom and charged particles, as well as the interaction between clusters of charged particles, are presented. These approximations are expressed in terms of physical and geometrical properties of the bodies such as the entire charge, the location of the center of charge, and the pseudo-inertia tensor about the center of charge of the clusters. Further, a novel substructuring scheme is introduced to implement the presented far-field potential evaluations in a binary tree framework as opposed to the existing quadtree and octree strategies of implementing fast multipole method. Using the presented Lagrangian grids, the electrostatic potential is recursively calculated via sweeping two passes: assembly and disassembly. In the assembly pass, adjacent charged bodies are combined together to form new clusters. Then, the potential field of each cluster due to its interaction with faraway resulting clusters is recursively calculated in the disassembly pass. The method is highly compatible with multibody dynamic schemes to model coarse-grained biopolymers. Since the proposed method takes advantage of constant physical and geometrical properties of rigid clusters, improvement in the overall computational cost is observed comparing to the tradition application of fast multipole method.

  20. Using a binary logistic regression method and GIS for evaluating and mapping the groundwater spring potential in the Sultan Mountains (Aksehir, Turkey)

    Science.gov (United States)

    Ozdemir, Adnan

    2011-07-01

    SummaryThe purpose of this study is to produce a groundwater spring potential map of the Sultan Mountains in central Turkey, based on a logistic regression method within a Geographic Information System (GIS) environment. Using field surveys, the locations of the springs (440 springs) were determined in the study area. In this study, 17 spring-related factors were used in the analysis: geology, relative permeability, land use/land cover, precipitation, elevation, slope, aspect, total curvature, plan curvature, profile curvature, wetness index, stream power index, sediment transport capacity index, distance to drainage, distance to fault, drainage density, and fault density map. The coefficients of the predictor variables were estimated using binary logistic regression analysis and were used to calculate the groundwater spring potential for the entire study area. The accuracy of the final spring potential map was evaluated based on the observed springs. The accuracy of the model was evaluated by calculating the relative operating characteristics. The area value of the relative operating characteristic curve model was found to be 0.82. These results indicate that the model is a good estimator of the spring potential in the study area. The spring potential map shows that the areas of very low, low, moderate and high groundwater spring potential classes are 105.586 km 2 (28.99%), 74.271 km 2 (19.906%), 101.203 km 2 (27.14%), and 90.05 km 2 (24.671%), respectively. The interpretations of the potential map showed that stream power index, relative permeability of lithologies, geology, elevation, aspect, wetness index, plan curvature, and drainage density play major roles in spring occurrence and distribution in the Sultan Mountains. The logistic regression approach has not yet been used to delineate groundwater potential zones. In this study, the logistic regression method was used to locate potential zones for groundwater springs in the Sultan Mountains. The evolved model

  1. Soil Stabilization Methods with Potential for Application at the Nevada National Security Site: A Literature Review

    Energy Technology Data Exchange (ETDEWEB)

    Shillito, Rose [DRI; Fenstermaker, Lynn [DRI

    2014-01-01

    Nuclear testing at the Nevada National Security Site (NNSS) has resulted in large areas of surficial radionuclide-contaminated soils. Much of the radionuclide contamination is found at or near the soil surface, and due to the dry climate setting, and the long half-life of radioactive isotopes, soil erosion poses a long-term health risk at the NNSS. The objective of this literature review is to present a survey of current stabilization methods used for minimizing soil erosion, both by water and wind. The review focuses on in situ uses of fundamental chemical and physical mechanisms for soil stabilization. A basic overview of the physical and chemical properties of soil is also presented to provide a basis for assessing stabilization methods. Some criteria for stabilization evaluation are identified based on previous studies at the NNSS. Although no specific recommendations are presented as no stabilization method, alone or in combination, will be appropriate in all circumstances, discussions of past and current stabilization procedures and specific soil tests that may aid in current or future soil stabilization activities at the NNSS are presented. However, not all Soils Corrective Action Sites (CASs) or Corrective Action Units (CAUs) will require stabilization of surficial radionuclide-contaminated soils. Each Soils CAS or CAU should be evaluated for site-specific conditions to determine if soil stabilization is necessary or practical for a given specific site closure alternative. If stabilization is necessary, then a determination will be made as to which stabilization technique is the most appropriate for that specific site.

  2. Potential benefit of the CT adaptive statistical iterative reconstruction method for pediatric cardiac diagnosis

    Science.gov (United States)

    Miéville, Frédéric A.; Ayestaran, Paul; Argaud, Christophe; Rizzo, Elena; Ou, Phalla; Brunelle, Francis; Gudinchet, François; Bochud, François; Verdun, Francis R.

    2010-04-01

    Adaptive Statistical Iterative Reconstruction (ASIR) is a new imaging reconstruction technique recently introduced by General Electric (GE). This technique, when combined with a conventional filtered back-projection (FBP) approach, is able to improve the image noise reduction. To quantify the benefits provided on the image quality and the dose reduction by the ASIR method with respect to the pure FBP one, the standard deviation (SD), the modulation transfer function (MTF), the noise power spectrum (NPS), the image uniformity and the noise homogeneity were examined. Measurements were performed on a control quality phantom when varying the CT dose index (CTDIvol) and the reconstruction kernels. A 64-MDCT was employed and raw data were reconstructed with different percentages of ASIR on a CT console dedicated for ASIR reconstruction. Three radiologists also assessed a cardiac pediatric exam reconstructed with different ASIR percentages using the visual grading analysis (VGA) method. For the standard, soft and bone reconstruction kernels, the SD is reduced when the ASIR percentage increases up to 100% with a higher benefit for low CTDIvol. MTF medium frequencies were slightly enhanced and modifications of the NPS shape curve were observed. However for the pediatric cardiac CT exam, VGA scores indicate an upper limit of the ASIR benefit. 40% of ASIR was observed as the best trade-off between noise reduction and clinical realism of organ images. Using phantom results, 40% of ASIR corresponded to an estimated dose reduction of 30% under pediatric cardiac protocol conditions. In spite of this discrepancy between phantom and clinical results, the ASIR method is as an important option when considering the reduction of radiation dose, especially for pediatric patients.

  3. Use of the piezoelectric film for the determination of cracks and defects - the passive and active electric potential CT method

    International Nuclear Information System (INIS)

    Kubo, S; Sakagami, T; Suzuki, T; Maeda, T; Nakatani, K

    2008-01-01

    The passive and active electric potential CT method was proposed by using piezoelectric film for identification of cracks and defects. This method is based on the principle of mutual conversion between mechanical strains and electric potential of piezoelectric material. A smart-layer was constructed using the piezoelectric film, and attached on a structure with a defect. When the structure was subjected to a mechanical load, the electric potential distribution appeared passively on the piezoelectric film due to the direct piezoelectric effect. The defect can be identified from the distribution with the help of inverse analysis. It was found that the crack could be identified reasonably, although the defect depth was not well estimated for the defects located far from the layer. When the electric signal was input to the smart-layer, acoustic wave was actively emitted from the layer due to the inverse piezoelectric effect, and a reflected wave was received on the layer. It was found that the depth of the defect could be estimated well. The simultaneous use of the passive method and the active method is promising for the identification of the defect.

  4. An Effective Method for Detecting Potential Woodland Vernal Pools Using High-Resolution LiDAR Data and Aerial Imagery

    Directory of Open Access Journals (Sweden)

    Qiusheng Wu

    2014-11-01

    Full Text Available Effective conservation of woodland vernal pools—important components of regional amphibian diversity and ecosystem services—depends on locating and mapping these pools accurately. Current methods for identifying potential vernal pools are primarily based on visual interpretation and digitization of aerial photographs, with variable accuracy and low repeatability. In this paper, we present an effective and efficient method for detecting and mapping potential vernal pools using stochastic depression analysis with additional geospatial analysis. Our method was designed to take advantage of high-resolution light detection and ranging (LiDAR data, which are becoming increasingly available, though not yet frequently employed in vernal pool studies. We successfully detected more than 2000 potential vernal pools in a ~150 km2 study area in eastern Massachusetts. The accuracy assessment in our study indicated that the commission rates ranged from 2.5% to 6.0%, while the proxy omission rate was 8.2%, rates that are much lower than reported errors of previous vernal pool studies conducted in the northeastern United States. One significant advantage of our semi-automated approach for vernal pool identification is that it may reduce inconsistencies and alleviate repeatability concerns associated with manual photointerpretation methods. Another strength of our strategy is that, in addition to detecting the point-based vernal pool locations for the inventory, the boundaries of vernal pools can be extracted as polygon features to characterize their geometric properties, which are not available in the current statewide vernal pool databases in Massachusetts.

  5. Potential Use of Lime as Nitric Acid Source for Alternative Electrolyte Fuel-Cell Method

    Science.gov (United States)

    Christianto, V.; Smarandache, Florentin

    2011-04-01

    Despite growing popularity for the use of biofuel and other similar methods to generate renewable energy sources from natural plantation in recent years, there is also growing concern over its disadvantage, i.e. that the energy use of edible plants may cause unwanted effects, because the plantation price tends to increase following the oil price. Therefore an alternative solution to this problem is to find `natural plantation' which have no direct link to `food chain' (for basic foods, such as palm oil etc.).

  6. Potential methods for determination of crack length of specimens in fracture mechanics

    International Nuclear Information System (INIS)

    Russenberger, M.E.

    1979-01-01

    For a wide and general use of neutron radiography in materials testing, transportable neutron sources are required which are strong enough for satisfactory pictures at a permissible radiation exposure time. These neutron sources are still lacking, and this shartage must be met by the development of better sources and imaging techniques which make better use of the given neutron flux- A simple method is presented that provides a better image quality due to a better absorption of neutrons, a larger amount of conversion radiation detected by the film, and reduced intrinsic unshapness. (orig.) [de

  7. Potential of high resolution protein mapping as a method of monitoring the human immune system

    International Nuclear Information System (INIS)

    Anderson, N.L.; Anderson, N.G

    1980-01-01

    Immunology traditionally deals with complex cellular systems and heterogeneous mixtures of effector molecules (primarily antibodies). Some sense has emerged from this chaos through the use of functional assays. Such an approach however naturally leaves a great deal undiscovered since the assays are simple and the assayed objects are complex. In this chapter some experimental approaches to immunological problems are described using high-resolution two-dimensional electrophoresis, a method that can resolve thousands of proteins and can thus begin to treat immunological entities at their appropriate level of complexity. In addition, the possible application of this work to the problem of monitoring events in the individual human immune system are discussed

  8. Method of Observation and their Effects in the Selection of Potential Football Goalkeepers

    Directory of Open Access Journals (Sweden)

    Zerf Mohammed

    2017-11-01

    Full Text Available The criteria and methods for goalkeeper selection are more strict and complex than those of field players. Founded on its principles, the present study tried to examine the strengths and weaknesses of selection process practised by Algerian coaches. Interpret by Algerian scientists in their subjectivity in evaluating the amount of body fat and its effect on physical performance. Seen it's built with the naked eye. Confirmed by FIFA in two categories normal vs overweight, they should work harder under these conditions. For this proposal, eight teams from the leagues of Oran, Algeria Championship second division were involved in the study. Their goalkeepers were classified into the following groups: total (GK = 28, Main goalkeeper (MG = 14 and replacement goalkeeper (RG = 14. Tested at the end of the outward phase by penalty kicks test, ‘T’ Drill Test, Ruler Drop Test (TR and anthropometric parameters (BH, BMI, BFP, BW. Backed on the applied statistical where our total sample is categorised in overweight, as well as no statistically significant differences between the two groups in all the comparisons practised. Our results confirm the weaknesses of traditional methods. Admit by similar studies in their subjective in evaluating the amount of body fat and its effect on physical performance correlate to anthropometric measurement.

  9. A simple method of equine limb force vector analysis and its potential applications

    Directory of Open Access Journals (Sweden)

    Sarah Jane Hobbs

    2018-02-01

    Full Text Available Background Ground reaction forces (GRF measured during equine gait analysis are typically evaluated by analyzing discrete values obtained from continuous force-time data for the vertical, longitudinal and transverse GRF components. This paper describes a simple, temporo-spatial method of displaying and analyzing sagittal plane GRF vectors. In addition, the application of statistical parametric mapping (SPM is introduced to analyse differences between contra-lateral fore and hindlimb force-time curves throughout the stance phase. The overall aim of the study was to demonstrate alternative methods of evaluating functional (asymmetry within horses. Methods GRF and kinematic data were collected from 10 horses trotting over a series of four force plates (120 Hz. The kinematic data were used to determine clean hoof contacts. The stance phase of each hoof was determined using a 50 N threshold. Vertical and longitudinal GRF for each stance phase were plotted both as force-time curves and as force vector diagrams in which vectors originating at the centre of pressure on the force plate were drawn at intervals of 8.3 ms for the duration of stance. Visual evaluation was facilitated by overlay of the vector diagrams for different limbs. Summary vectors representing the magnitude (VecMag and direction (VecAng of the mean force over the entire stance phase were superimposed on the force vector diagram. Typical measurements extracted from the force-time curves (peak forces, impulses were compared with VecMag and VecAng using partial correlation (controlling for speed. Paired samples t-tests (left v. right diagonal pair comparison and high v. low vertical force diagonal pair comparison were performed on discrete and vector variables using traditional methods and Hotelling’s T2 tests on normalized stance phase data using SPM. Results Evidence from traditional statistical tests suggested that VecMag is more influenced by the vertical force and impulse, whereas

  10. A method for selecting potential geosites. The case of glacial geosites in the Chablais area (French and Swiss Prealps)

    Science.gov (United States)

    Perret, Amandine; Reynard, Emmanuel

    2014-05-01

    Since 2009, an Interreg IVA project (123 Chablais), dealing with the promotion of natural and cultural heritage in the Chablais area, has been developed. It is linked to the creation of the Chablais Geopark. In a context of development of smart forms of tourism, the objective was to develop a strategy promoting the glacial heritage to a wide public in an area where the glaciers have almost disappeared. The recognition of specific places as geoheritage is the result of a double process: a scientific one, based on more or less sophisticated methods, and a social one, that is the acknowledgment by the society. One of the first scientific tasks is to produce a list of "potential geosites" that will be assessed in more details. However, this selection is often a weak point of inventories. It often seems like a "black box" without any transparency. In this project (123 Chablais) we carried out an inventory of glacial geosites, using the method developed by Reynard et al. (2007, 2012). However, a method has been created to enlighten the selection process, and to enhance choices in geoheritage management. As it was not possible to consider all sites in the Chablais area, a mixed selection approach was developed, halfway between completeness and specificity (Martin, 2012). The first step was the creation of a list of "points of interest", established using different sources: literature review, fieldwork and use of GIS to cross information. A selection was then performed according to two criteria: correspondence with a glacial stage (time axis) and belonging to a type of forms (spatial axis). Finally, selected sites aimed at providing a representative overview of the regional glacial witnesses. Therefore, representative sites of the regional geology were selected as well as sites presenting regional peculiarities Temporal and spatial attributes were given to the 101 points of interest identified. From a temporal point of view, this inventory aimed at presenting the main

  11. Donating blood for research: a potential method for enhancing customer satisfaction of permanently deferred blood donors.

    Science.gov (United States)

    Waller, Daniel; Thijsen, Amanda; Garradd, Allira; Hayman, Jane; Smith, Geoff

    2017-01-01

    Each year, a large number of individuals in Australia are deferred from donating blood. A deferral may have a negative impact on donor satisfaction and subsequent word-of-mouth communication. The Australian Red Cross Blood Service (the Blood Service) is, therefore, investigating options for managing service interactions with deferred donors to maintain positive relationships. While public research institutes in Australia have established independent research donor registries, other countries provide programmes allowing deferred donors to donate blood for research via blood collection agencies. This study examined attitudes towards donating blood for research use in a sample of permanently deferred Australian donors. Donors permanently deferred because of a risk of variant Creutzfeldt-Jakob disease (n=449) completed a postal survey that examined attitudes towards research donation. The majority of participants were interested in donating blood for research (96%), and joining a registry of research donors (93%). Participants preferred to donate for transfusion or clinical research, and were willing to travel large distances. Results indicated that positive attitudes towards the Blood Service would be extended if the opportunity to donate blood was provided. These findings indicate a desire for continued engagement with the Blood Service despite deferral. Donating blood for research is a potential way of maintaining positive relationships with permanently deferred donors which also benefits the health research community. Through maintaining positive relationships with deferred donors, positive word-of-mouth activity can be stimulated. Further work is needed to determine the feasibility of implementing research donation through the Blood Service in Australia.

  12. Potentials of NO{sub X} emission reduction methods in SI hydrogen engines: Simulation study

    Energy Technology Data Exchange (ETDEWEB)

    Safari, H.; Jazayeri, S.A. [Department of Mechanical Engineering, K.N. Toosi University of Technology, No.15, Pardis Street, Vanak Square, Tehran (Iran); Ebrahimi, R. [Department of Aerospace Engineering, K.N. Toosi University of Technology, 4th Tehranpars Square, East Vafadar Street, Tehran (Iran)

    2009-01-15

    The ever increasing cost of hydrocarbon fuels and more stringent emission standards may resolve challenges in producing hydrogen and using it as an alternative fuel in industries. Internal combustion engines are well-established technology and hydrogen fuel in such engines is considered as an attractive choice in exploiting clean, efficient and renewable hydrogen energy. This work presents an improved thermo-kinetics model for simulation of hydrogen combustion in SI engines. The turbulent propagating flame is modeled using turbulent burning velocity model. During combustion the charge is divided into three zones containing unburned charge, flame and burned gas. The adiabatic flame is assumed to be in thermodynamic equilibrium while the detailed chemical kinetics scheme is considered for burned and unburned zones. The results were first validated against published experiments. Good agreements were obtained between simulation and experiment for varying equivalence ratio, ignition timing and compression ratio. Detailed analysis of engine NO{sub X} emission was performed afterward. The lean-burn and EGR strategies' potentials were examined by the current model. The effects of different amounts of cooled dry EGR and hot wet EGR on the NO{sub X} emission, engine power output and indicated thermal efficiency were investigated and compared theoretically. (author)

  13. Computational Methods to Assess the Production Potential of Bio-Based Chemicals.

    Science.gov (United States)

    Campodonico, Miguel A; Sukumara, Sumesh; Feist, Adam M; Herrgård, Markus J

    2018-01-01

    Elevated costs and long implementation times of bio-based processes for producing chemicals represent a bottleneck for moving to a bio-based economy. A prospective analysis able to elucidate economically and technically feasible product targets at early research phases is mandatory. Computational tools can be implemented to explore the biological and technical spectrum of feasibility, while constraining the operational space for desired chemicals. In this chapter, two different computational tools for assessing potential for bio-based production of chemicals from different perspectives are described in detail. The first tool is GEM-Path: an algorithm to compute all structurally possible pathways from one target molecule to the host metabolome. The second tool is a framework for Modeling Sustainable Industrial Chemicals production (MuSIC), which integrates modeling approaches for cellular metabolism, bioreactor design, upstream/downstream processes, and economic impact assessment. Integrating GEM-Path and MuSIC will play a vital role in supporting early phases of research efforts and guide the policy makers with decisions, as we progress toward planning a sustainable chemical industry.

  14. Regge-pole description of potential scattering by means of the phase-integral method

    International Nuclear Information System (INIS)

    Amaha, A.

    1992-01-01

    The application of Regge-pole theory to different atomic and molecular scattering has shown to have promising interpretational power in the differential cross sections. Differential cross sections can be analysed in terms of interference between the 'background' amplitude and a few Regge-pole positions of the scattering matrix (S matrix) representing surface waves around the interaction region. By the analytic continuation of the radial Schroedinger differential equation into the complex plane of angular momentum one can determine the analytic properties of the S matrix which contains the physical information in the scattering processes. For interaction potentials fulfilling certain properties, the study of the S matrix leads to the study of the F matrix introduced by Froeman and Froeman for the treatment of connection problems for phase-integral solutions of the differential equation. In this thesis the quantum mechanical scattering problem is analysed in the framework of Regge-pole theory with the use of the complex-angular-momentum formalism. To determine the S matrix, the relevant F matrix elements which give the stokes constants are derived and their properties are studied. The poles of the S matrix for particular complex values of the angular momentum quantum number are the Regge-poles. Using the Regge-pole positions and residues together with the background integral, the differential cross sections are calculated and compared with corresponding partial-wave representations

  15. Meniscus repair and regeneration: review on current methods and research potential

    Directory of Open Access Journals (Sweden)

    C Scotti

    2013-01-01

    Full Text Available Meniscus regeneration is an unsolved clinical challenge. Despite the wide acceptance of the degenerative consequences of meniscectomy, no surgical procedure has succeeded to date in regenerating a functional and long-lasting meniscal fibrocartilage. Research proposed a number of experimental approaches encompassing all the typical strategies of regenerative medicine: cell-free scaffolds, gene therapy, intra-articular delivery of progenitor cells, biological glues for enhanced bonding of reparable tears, partial and total tissue engineered meniscus replacement. None of these approaches has been completely successful and can be considered suitable for all patients, as meniscal tears require specific and patient-related treatments depending on the size and type of lesion. Recent advances in cell biology, biomaterial science and bioengineering (e.g., bioreactors have now the potential to drive meniscus regeneration into a series of clinically relevant strategies. In this tutorial paper, the clinical need for meniscus regeneration strategies will be explained, and past and current experimental studies on meniscus regeneration will be reported.

  16. A new approach to the method of source-sink potentials for molecular conduction

    Energy Technology Data Exchange (ETDEWEB)

    Pickup, Barry T., E-mail: B.T.Pickup@sheffield.ac.uk, E-mail: P.W.Fowler@sheffield.ac.uk; Fowler, Patrick W., E-mail: B.T.Pickup@sheffield.ac.uk, E-mail: P.W.Fowler@sheffield.ac.uk; Borg, Martha [Department of Chemistry, University of Sheffield, Sheffield S3 7HF (United Kingdom); Sciriha, Irene [Department of Mathematics, University of Malta, Msida (Malta)

    2015-11-21

    We re-derive the tight-binding source-sink potential (SSP) equations for ballistic conduction through conjugated molecular structures in a form that avoids singularities. This enables derivation of new results for families of molecular devices in terms of eigenvectors and eigenvalues of the adjacency matrix of the molecular graph. In particular, we define the transmission of electrons through individual molecular orbitals (MO) and through MO shells. We make explicit the behaviour of the total current and individual MO and shell currents at molecular eigenvalues. A rich variety of behaviour is found. A SSP device has specific insulation or conduction at an eigenvalue of the molecular graph (a root of the characteristic polynomial) according to the multiplicities of that value in the spectra of four defined device polynomials. Conduction near eigenvalues is dominated by the transmission curves of nearby shells. A shell may be inert or active. An inert shell does not conduct at any energy, not even at its own eigenvalue. Conduction may occur at the eigenvalue of an inert shell, but is then carried entirely by other shells. If a shell is active, it carries all conduction at its own eigenvalue. For bipartite molecular graphs (alternant molecules), orbital conduction properties are governed by a pairing theorem. Inertness of shells for families such as chains and rings is predicted by selection rules based on node counting and degeneracy.

  17. Oxygen Reduction on Gas-Diffusion Electrodes for Phosphoric Acid Fuel Cells by a Potential Decay Method

    DEFF Research Database (Denmark)

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

    1995-01-01

    The reduction of gaseous oxygen on carbon supported platinum electrodes has been studied at 150 degrees C with polarization and potential decay measurements. The electrolyte was either 100 weight percent phosphoric acid or that acid with a fluorinated additive, potassium perfluorohexanesulfonate ......6F13SO3K). The pseudo-Tafel curves of the overpotential vs. log (ii(L)/(i(L) - i)) show a two-slope behavior, probably due to different adsorption mechanisms. The potential relaxations as functions of log (t + tau) and log (-d eta/dt) have been plotted. The variations of these slopes...

  18. Retention of data in heat-damaged SIM cards and potential recovery methods.

    Science.gov (United States)

    Jones, B J; Kenyon, A J

    2008-05-02

    Examination of various SIM cards and smart card devices indicates that data may be retained in SIM card memory structures even after heating to temperatures up to 450 degrees C, which the National Institute of Standards and Technology (NIST) has determined to be approximately the maximum average sustained temperature at desk height in a house fire. However, in many cases, and certainly for temperatures greater than 450 degrees C, the SIM card chip has suffered structural or mechanical damage that renders simple probing or rewiring ineffective. Nevertheless, this has not necessarily affected the data, which is stored as charge in floating gates, and alternative methods for directly accessing the stored charge may be applicable.

  19. A simple method of equine limb force vector analysis and its potential applications.

    Science.gov (United States)

    Hobbs, Sarah Jane; Robinson, Mark A; Clayton, Hilary M

    2018-01-01

    Ground reaction forces (GRF) measured during equine gait analysis are typically evaluated by analyzing discrete values obtained from continuous force-time data for the vertical, longitudinal and transverse GRF components. This paper describes a simple, temporo-spatial method of displaying and analyzing sagittal plane GRF vectors. In addition, the application of statistical parametric mapping (SPM) is introduced to analyse differences between contra-lateral fore and hindlimb force-time curves throughout the stance phase. The overall aim of the study was to demonstrate alternative methods of evaluating functional (a)symmetry within horses. GRF and kinematic data were collected from 10 horses trotting over a series of four force plates (120 Hz). The kinematic data were used to determine clean hoof contacts. The stance phase of each hoof was determined using a 50 N threshold. Vertical and longitudinal GRF for each stance phase were plotted both as force-time curves and as force vector diagrams in which vectors originating at the centre of pressure on the force plate were drawn at intervals of 8.3 ms for the duration of stance. Visual evaluation was facilitated by overlay of the vector diagrams for different limbs. Summary vectors representing the magnitude (VecMag) and direction (VecAng) of the mean force over the entire stance phase were superimposed on the force vector diagram. Typical measurements extracted from the force-time curves (peak forces, impulses) were compared with VecMag and VecAng using partial correlation (controlling for speed). Paired samples t -tests (left v. right diagonal pair comparison and high v. low vertical force diagonal pair comparison) were performed on discrete and vector variables using traditional methods and Hotelling's T 2 tests on normalized stance phase data using SPM. Evidence from traditional statistical tests suggested that VecMag is more influenced by the vertical force and impulse, whereas VecAng is more influenced by the

  20. Approximate analytical solution of the Dirac equation for pseudospin symmetry with modified Po schl-Teller potential and trigonometric Scarf II non-central potential using asymptotic iteration method

    International Nuclear Information System (INIS)

    Pratiwi, B N; Suparmi, A; Cari, C; Yunianto, M; Husein, A S

    2016-01-01

    We apllied asymptotic iteration method (AIM) to obtain the analytical solution of the Dirac equation in case exact pseudospin symmetry in the presence of modified Pcischl- Teller potential and trigonometric Scarf II non-central potential. The Dirac equation was solved by variables separation into one dimensional Dirac equation, the radial part and angular part equation. The radial and angular part equation can be reduced into hypergeometric type equation by variable substitution and wavefunction substitution and then transform it into AIM type equation to obtain relativistic energy eigenvalue and wavefunctions. Relativistic energy was calculated numerically by Matlab software. And then relativistic energy spectrum and wavefunctions were visualized by Matlab software. The results show that the increase in the radial quantum number n_r causes decrease in the relativistic energy spectrum. The negative value of energy is taken due to the pseudospin symmetry limit. Several quantum wavefunctions were presented in terms of the hypergeometric functions. (paper)

  1. A Laplace transform/potential-theoretic method for acoustic propagation in subsonic flows

    International Nuclear Information System (INIS)

    Hariharan, S.I.; Sawyer, Scott; Dane Quinn, D.

    2003-01-01

    This paper introduces a competitive computational approach for determining time-dependent far-field sound generated by subsonic flows around lifting airfoils. The procedure assumes the linearity of the sound field away from a bounded region surrounding the airfoil. It is assumed that the sound pressure on the boundary of this enclosed region (referred to as the Kirchhoff surface) is specified, possibly by another procedure such as solving the full Euler equations. Away from the Kirchhoff surface, the Euler equations are linearized about a uniform mean flow. It is well known that linearized Euler equations can be uncoupled into a scalar convective wave equation. However, due to the anisotropy present in the convective wave equation, it is difficult to compute solutions. In this context, direct numerical simulation of the convective wave equation requires proper numerical descriptions of far-field boundary conditions which is a non-trivial task. Moreover, if accurate far-field conditions can be formulated, the computational cost of direct simulation can be prohibitive even in a modest computational domain. In this paper, we present an alternate solution procedure. First, the problem is transformed via the Laplace transform (with appropriate initial conditions) into a reduced wave equation. The convective term in the reduced wave equation is removed using a dependent variable transformation. Then we use Gothert's rule, to obtain a Helmholtz like equation with complex wave number, which is subsequently solved using double layer potential theory. Finally upon application of numerical inverse Laplace transform techniques, far-field acoustic pressure is obtained as a function of space and time

  2. Paired-pulse flash-visual evoked potentials: new methods revive an old test.

    Science.gov (United States)

    Cantello, Roberto; Strigaro, Gionata; Prandi, Paolo; Varrasi, Claudia; Mula, Marco; Monaco, Francesco

    2011-08-01

    We aimed at reviving with modern technology the paired flash-visual evoked potential (F-VEP) testing of the visual system excitability. In the 1960s, methodological problems hindered this test, which was expected to provide important physiologic information. We studied 22 consenting healthy subjects (10 men). We recorded F-VEPs from electrodes over occipital and central brain regions. We delivered single flashes, mixed at random to flash pairs at the interstimulus interval (ISI) of 333, 125, 62.5, 50, 33, and 16.5 ms, (i.e. an internal frequency (IF) of 3, 8, 16, 20, 30, and 60 Hz). Recordings were performed with the subject's eyes closed and opened. The F-VEP was split into a "main complex" and an "afterdischarge", which we analyzed statistically in relation to the eye state (closed or open) and to the changes due to paired stimulation. The eye state affected the single F-VEP size, latency and shape significantly (p<0.05). On paired stimulation, the test (second) F-VEP exhibited significant (p<0.05), ISI-dependent size changes, such as a progressive decrease for ISIs from 62.5 to 16.5 ms (IFs of 16-60 Hz), whose timing/amount varied significantly (p<0.05) according to the eye state and to the F-VEP epoch considered. Suppression of the test F-VEP was never complete, even for the shortest ISI (ISI=16.5 ms, IF=60 Hz). The eye state (closed or open) must be considered meticulously when studying F-VEPs. F-VEP changes on paired stimulation express neural inhibition within the visual system, which can be depicted as ISI-dependent curves. Modern equipment and simplified measures render this an easy test, with statistical validity, providing specific information on the excitability properties of the visual system. Copyright © 2011 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  3. A multi-criteria, ecosystem-service value method used to assess catchment suitability for potential wetland reconstruction in Denmark

    DEFF Research Database (Denmark)

    Odgaard, Mette Vestergaard; Turner, Katrine Grace; Bøcher, Peder Klith

    2017-01-01

    Wetlands provide a range of ecosystem services such as drought resistance, flood resistance, nutrient deposition, biodiversity, etc. This study presents a new multi-criteria, ecosystems service value-driven method to drive the optimal placement of restored wetlands in terms of maximizing selected...... for potential wetland reconstruction (i.e. restoration)? Five key ecosystem services indicators produced or affected by wetlands in Denmark were mapped (recreational potential, biodiversity, nitrogen mitigation potential, inverse land rent, and flash-flood risk). These services were compared to current...... ecosystem services which a wetland can provide or affect. We aim to answer two questions: 1) which of the ecosystem services indicators defines the placement of wetlands today? 2) Based on the ecosystem services indicator assessment, what are the recommendations for future selection of catchments...

  4. pd Scattering Using a Rigorous Coulomb Treatment: Reliability of the Renormalization Method for Screened-Coulomb Potentials

    International Nuclear Information System (INIS)

    Hiratsuka, Y.; Oryu, S.; Gojuki, S.

    2011-01-01

    Reliability of the screened Coulomb renormalization method, which was proposed in an elegant way by Alt-Sandhas-Zankel-Ziegelmann (ASZZ), is discussed on the basis of 'two-potential theory' for the three-body AGS equations with the Coulomb potential. In order to obtain ASZZ's formula, we define the on-shell Moller function, and calculate it by using the Haeringen criterion, i. e. 'the half-shell Coulomb amplitude is zero'. By these two steps, we can finally obtain the ASZZ formula for a small Coulomb phase shift. Furthermore, the reliability of the Haeringen criterion is thoroughly checked by a numerically rigorous calculation for the Coulomb LS-type equation. We find that the Haeringen criterion can be satisfied only in the higher energy region. We conclude that the ASZZ method can be verified in the case that the on-shell approximation to the Moller function is reasonable, and the Haeringen criterion is reliable. (author)

  5. Characterizing Ductile Damage and Failure: Application of the Direct Current Potential Drop Method to Uncracked Tensile Specimens

    OpenAIRE

    Brinnel, V.; Döbereiner, B.; Münstermann, Sebastian

    2014-01-01

    Modern high-strength steels exhibit excellent ductility properties but their application is hindered by traditional design rules. A characterization of necessary safety margins for the ductile failure of these steels is therefore required. Direct observation of ductile damage within tests is currently not possible, only limited measurements can be made with synchrotron or X-ray radiation facilities. The direct current potential drop (DCPD) method can determine ductile crack propagation with l...

  6. Applying the trigger review method after a brief educational intervention: potential for teaching and improving safety in GP specialty training?

    OpenAIRE

    McKay, John; de Wet, Carl; Kelly, Moya; Bowie, Paul

    2013-01-01

    Background:\\ud The Trigger Review Method (TRM) is a structured approach to screening clinical records for undetected patient safety incidents (PSIs) and identifying learning and improvement opportunities. In Scotland, TRM participation can inform GP appraisal and has been included as a core component of the national primary care patient safety programme that was launched in March 2013. However, the clinical workforce needs up-skilled and the potential of TRM in GP training has yet to be teste...

  7. An accurate potential energy surface for the F + H2 → HF + H reaction by the coupled-cluster method

    International Nuclear Information System (INIS)

    Chen, Jun; Sun, Zhigang; Zhang, Dong H.

    2015-01-01

    A three dimensional potential energy surface for the F + H 2 → HF + H reaction has been computed by the spin unrestricted coupled cluster method with singles, doubles, triples, and perturbative quadruples [UCCSDT(2) Q ] using the augmented correlation-consistent polarised valence quadruple zeta basis set for the fluorine atom and the correlation-consistent polarised valence quadruple zeta basis set for the hydrogen atom. All the calculations are based on the restricted open-shell Hartree-Fock orbitals, together with the frozen core approximations, and the UCCSD(T)/complete basis set (CBS) correction term was included. The global potential energy surface was calculated by fitting the sampled ab initio points without any scaling factor for the correlation energy part using a neutral network function method. Extensive dynamics calculations have been carried out on the potential energy surface. The reaction rate constants, integral cross sections, product rotational states distribution, and forward and backward scattering as a function of collision energy of the F + HD → HF + D, F + HD → DF + H, and F + H 2 reaction, were calculated by the time-independent quantum dynamics scattering theory using the new surface. The satisfactory agreement with the reported experimental observations previously demonstrates the accuracy of the new potential energy surface

  8. A high-throughput and quantitative method to assess the mutagenic potential of translesion DNA synthesis

    Science.gov (United States)

    Taggart, David J.; Camerlengo, Terry L.; Harrison, Jason K.; Sherrer, Shanen M.; Kshetry, Ajay K.; Taylor, John-Stephen; Huang, Kun; Suo, Zucai

    2013-01-01

    Cellular genomes are constantly damaged by endogenous and exogenous agents that covalently and structurally modify DNA to produce DNA lesions. Although most lesions are mended by various DNA repair pathways in vivo, a significant number of damage sites persist during genomic replication. Our understanding of the mutagenic outcomes derived from these unrepaired DNA lesions has been hindered by the low throughput of existing sequencing methods. Therefore, we have developed a cost-effective high-throughput short oligonucleotide sequencing assay that uses next-generation DNA sequencing technology for the assessment of the mutagenic profiles of translesion DNA synthesis catalyzed by any error-prone DNA polymerase. The vast amount of sequencing data produced were aligned and quantified by using our novel software. As an example, the high-throughput short oligonucleotide sequencing assay was used to analyze the types and frequencies of mutations upstream, downstream and at a site-specifically placed cis–syn thymidine–thymidine dimer generated individually by three lesion-bypass human Y-family DNA polymerases. PMID:23470999

  9. The Potential of Subjective Semantic Methods in Exploring the Perception of Architecture

    Directory of Open Access Journals (Sweden)

    Vyrva A.U.,

    2016-01-01

    Full Text Available This research focuses on empirical explorations of psychological features and mechanisms of the percep¬tion of urban architecture and on the specifics of the perception of buildings of various architectural styles. The techniques employed included those of personality and architectural semantic differential and the Value Spectrum technique. Four factors were found to have a significant impact on an individual’s percep¬tion and understanding of architectural space: ‘passive-active’, ‘whole-split’, ‘open-closed’, and ‘expressive’. People tend to attribute more semantic features and values to listed buildings or buildings that bear witness of a certain historical period than to those buildings that look alike and represent a typical example of mass housing. No significant sex differences were found in the individuals’ evaluations of buildings. Consistent quantitative differences were revealed between the images of listed buildings and of mass housing. The paper describes the relevance of various research methods in explorations of architectural images.

  10. Constraining Basin Depth and Fault Displacement in the Malombe Basin Using Potential Field Methods

    Science.gov (United States)

    Beresh, S. C. M.; Elifritz, E. A.; Méndez, K.; Johnson, S.; Mynatt, W. G.; Mayle, M.; Atekwana, E. A.; Laó-Dávila, D. A.; Chindandali, P. R. N.; Chisenga, C.; Gondwe, S.; Mkumbwa, M.; Kalaguluka, D.; Kalindekafe, L.; Salima, J.

    2017-12-01

    The Malombe Basin is part of the Malawi Rift which forms the southern part of the Western Branch of the East African Rift System. At its southern end, the Malawi Rift bifurcates into the Bilila-Mtakataka and Chirobwe-Ntcheu fault systems and the Lake Malombe Rift Basin around the Shire Horst, a competent block under the Nankumba Peninsula. The Malombe Basin is approximately 70km from north to south and 35km at its widest point from east to west, bounded by reversing-polarity border faults. We aim to constrain the depth of the basin to better understand displacement of each border fault. Our work utilizes two east-west gravity profiles across the basin coupled with Source Parameter Imaging (SPI) derived from a high-resolution aeromagnetic survey. The first gravity profile was done across the northern portion of the basin and the second across the southern portion. Gravity and magnetic data will be used to constrain basement depths and the thickness of the sedimentary cover. Additionally, Shuttle Radar Topography Mission (SRTM) data is used to understand the topographic expression of the fault scarps. Estimates for minimum displacement of the border faults on either side of the basin were made by adding the elevation of the scarps to the deepest SPI basement estimates at the basin borders. Our preliminary results using SPI and SRTM data show a minimum displacement of approximately 1.3km for the western border fault; the minimum displacement for the eastern border fault is 740m. However, SPI merely shows the depth to the first significantly magnetic layer in the subsurface, which may or may not be the actual basement layer. Gravimetric readings are based on subsurface density and thus circumvent issues arising from magnetic layers located above the basement; therefore expected results for our work will be to constrain more accurate basin depth by integrating the gravity profiles. Through more accurate basement depth estimates we also gain more accurate displacement

  11. Verification of the Viability of Equipotential Switching Direct Current Potential Drop Method for Piping Wall Loss Monitoring with Signal Sensitivity Analysis

    International Nuclear Information System (INIS)

    Ryu, Kyung Ha; Hwang, Il Soon; Kim, Ji Hyun

    2008-01-01

    Flow accelerated corrosion (FAC) phenomenon of low alloy carbon steels in nuclear power plant has been known as one of major degradation mechanisms. It has a potential to cause nuclear pipe rupture accident which may directly impact on the plant reliability and safety. Recently, the equipotential switching direct current potential drop (ES-DCPD) method has been developed, by the present authors, as a method to monitor wall loss in a piping. This method can rapidly monitor the thinning of piping, utilizing either the wide range monitoring (WiRM) or the narrow range monitoring (NaRM) technique. WiRM is a method to monitor wide range of straight piping, whereas NaRM focuses significantly on a narrow range such as an elbow. WiRM and NaRM can improve the reliability of the current FAC screening method that is based on computer modeling on fluid flow conditions. In this paper, the measurements by ES-DCPD are performed with signal sensitivity analyses in the laboratory environment for extended period and showed the viability of ES-DCPD for real plant applications.

  12. Impedances of electrochemically impregnated nickel electrodes as functions of potential, KOH concentration, and impregnation method

    Science.gov (United States)

    Reid, Margaret A.

    1989-01-01

    Impedances of fifteen electrodes form each of the four U.S. manufactures were measured at 0.200 V vs. the Hg/HgO reference electrode. This corresponds to a voltage of 1.145 for a Ni/H2 cell. Measurements were also made of a representative sample of these at 0.44 V. At the higher voltage, the impedances were small and very similar, but at the lower voltage there were major differences between manufacturers. Electrodes from the same manufacturers showed only small differences. The impedances of electrodes from two manufacturers were considerably different in 26 percent KOH from those in 31 percent KOH. These preliminary results seen to correlate with the limited data from earlier life testing of cells from these manufacturers. The impedances of cells being tested for Space Station Freedom are being followed, and more impendance measurements of electrodes are being performed as functions of manufacturer, voltage, electrolyte concentration, and cycle history in hopes of finding better correlations of impedance with life.

  13. Resting-State Functional Connectivity in the Infant Brain: Methods, Pitfalls, and Potentiality

    Directory of Open Access Journals (Sweden)

    Chandler R. L. Mongerson

    2017-08-01

    Full Text Available Early brain development is characterized by rapid growth and perpetual reconfiguration, driven by a dynamic milieu of heterogeneous processes. Postnatal brain plasticity is associated with increased vulnerability to environmental stimuli. However, little is known regarding the ontogeny and temporal manifestations of inter- and intra-regional functional connectivity that comprise functional brain networks. Resting-state functional magnetic resonance imaging (rs-fMRI has emerged as a promising non-invasive neuroinvestigative tool, measuring spontaneous fluctuations in blood oxygen level dependent (BOLD signal at rest that reflect baseline neuronal activity. Over the past decade, its application has expanded to infant populations providing unprecedented insight into functional organization of the developing brain, as well as early biomarkers of abnormal states. However, many methodological issues of rs-fMRI analysis need to be resolved prior to standardization of the technique to infant populations. As a primary goal, this methodological manuscript will (1 present a robust methodological protocol to extract and assess resting-state networks in early infancy using independent component analysis (ICA, such that investigators without previous knowledge in the field can implement the analysis and reliably obtain viable results consistent with previous literature; (2 review the current methodological challenges and ethical considerations associated with emerging field of infant rs-fMRI analysis; and (3 discuss the significance of rs-fMRI application in infants for future investigations of neurodevelopment in the context of early life stressors and pathological processes. The overarching goal is to catalyze efforts toward development of robust, infant-specific acquisition, and preprocessing pipelines, as well as promote greater transparency by researchers regarding methods used.

  14. Resting-State Functional Connectivity in the Infant Brain: Methods, Pitfalls, and Potentiality.

    Science.gov (United States)

    Mongerson, Chandler R L; Jennings, Russell W; Borsook, David; Becerra, Lino; Bajic, Dusica

    2017-01-01

    Early brain development is characterized by rapid growth and perpetual reconfiguration, driven by a dynamic milieu of heterogeneous processes. Postnatal brain plasticity is associated with increased vulnerability to environmental stimuli. However, little is known regarding the ontogeny and temporal manifestations of inter- and intra-regional functional connectivity that comprise functional brain networks. Resting-state functional magnetic resonance imaging (rs-fMRI) has emerged as a promising non-invasive neuroinvestigative tool, measuring spontaneous fluctuations in blood oxygen level dependent (BOLD) signal at rest that reflect baseline neuronal activity. Over the past decade, its application has expanded to infant populations providing unprecedented insight into functional organization of the developing brain, as well as early biomarkers of abnormal states. However, many methodological issues of rs-fMRI analysis need to be resolved prior to standardization of the technique to infant populations. As a primary goal, this methodological manuscript will (1) present a robust methodological protocol to extract and assess resting-state networks in early infancy using independent component analysis (ICA), such that investigators without previous knowledge in the field can implement the analysis and reliably obtain viable results consistent with previous literature; (2) review the current methodological challenges and ethical considerations associated with emerging field of infant rs-fMRI analysis; and (3) discuss the significance of rs-fMRI application in infants for future investigations of neurodevelopment in the context of early life stressors and pathological processes. The overarching goal is to catalyze efforts toward development of robust, infant-specific acquisition, and preprocessing pipelines, as well as promote greater transparency by researchers regarding methods used.

  15. In operando observation system for electrochemical reaction by soft X-ray absorption spectroscopy with potential modulation method

    International Nuclear Information System (INIS)

    Nagasaka, Masanari; Kosugi, Nobuhiro; Yuzawa, Hayato; Horigome, Toshio

    2014-01-01

    In order to investigate local structures of electrolytes in electrochemical reactions under the same scan rate as a typical value 100 mV/s in cyclic voltammetry (CV), we have developed an in operando observation system for electrochemical reactions by soft X-ray absorption spectroscopy (XAS) with a potential modulation method. XAS spectra of electrolytes are measured by using a transmission-type liquid flow cell with built-in electrodes. The electrode potential is swept with a scan rate of 100 mV/s at a fixed photon energy, and soft X-ray absorption coefficients at different potentials are measured at the same time. By repeating the potential modulation at each fixed photon energy, it is possible to measure XAS of electrochemical reaction at the same scan rate as in CV. We have demonstrated successful measurement of the Fe L-edge XAS spectra of aqueous iron sulfate solutions and of the change in valence of Fe ions at different potentials in the Fe redox reaction. The mechanism of these Fe redox processes is discussed by correlating the XAS results with those at different scan rates

  16. YouTube as a potential training method for laparoscopic cholecystectomy.

    Science.gov (United States)

    Lee, Jun Suh; Seo, Ho Seok; Hong, Tae Ho

    2015-08-01

    The purpose of this study was to analyze the educational quality of laparoscopic cholecystectomy (LC) videos accessible on YouTube, one of the most important sources of internet-based medical information. The keyword 'laparoscopic cholecystectomy' was used to search on YouTube and the first 100 videos were analyzed. Among them, 27 videos were excluded and 73 videos were included in the study. An arbitrary score system for video quality, devised from existing LC guidelines, were used to evaluate the quality of the videos. Video demographics were analyzed by the quality and source of the video. Correlation analysis was performed. When analyzed by video quality, 11 (15.1%) were evaluated as 'good', 40 (54.8%) were 'moderate', and 22 (30.1%) were 'poor', and there were no differences in length, views per day, or number of likes, dislikes, and comments. When analyzed by source, 27 (37.0%) were uploaded by primary centers, 20 (27.4%) by secondary centers, 15 (20.5%) by tertiary centers, 5 (6.8%) by academic institutions, and 6 (8.2%) by commercial institutions. The mean score of the tertiary center group (6.0 ± 2.0) was significantly higher than the secondary center group (3.9 ± 1.4, P = 0.001). The video score had no correlation with views per day or number of likes. Many LC videos are accessible on YouTube with varying quality. Videos uploaded by tertiary centers showed the highest educational value. This discrepancy in video quality was not recognized by viewers. More videos with higher quality need to be uploaded, and an active filtering process is necessary.

  17. Methods for calculations of potential and producible associated with marine energies: case studies in the Channel - Atlantic

    International Nuclear Information System (INIS)

    Ledoux, Sebastien; Chotard, David; Mazeiraud, Vincent; Garcia, Nicolas; Saillard, Thibault; Mensencal, Yvon; Mouslim, Hakim

    2015-01-01

    Faced with the development of Marine Renewable Energy (MRE) in recent years and demand from regional public authorities to evaluate the energy potential of their coastal domains, it was necessary to design an integrated tool for determining, at the scale of a site and then a region, first the gross resource per energy type and then its technical potential followed by its technico-economic potential. In response to this need, Artelia mobilised its experts in maritime and river hydraulics and in energy with the aim of developing a tool dedicated to calculating MRE production capacities. With this operational objective in mind, ARTELIA undertook R and D actions in order to determine the state of the art in calculation methods and in tools already developed and in use in other European countries spearheading this activity, especially the United Kingdom (Atlas of UK Marine Renewable Energy Resources, ABPmer,) and the United States (in particular the work of the EPRI (Electric Power Research Institute)). The tool was then developed and applied successively in the framework of calculating the MRE potential of the coastal domain of the Poitou-Charentes region (client: Poitou-Charentes regional council), then through study assessments performed on the marine current power potential of Lower Normandy (client: DREAL Basse-Normandie) and on the MRE potential of the Aquitaine coast (client: Aquitaine regional council - GIP Littoral Aquitain). The tool allows for the assessment of the resources, technical and techno-economic potentials It has been applied to the following topics: marine current power (offshore and in estuaries and rivers), wave power (offshore, near-shore and coastal) and wind power (offshore and floating turbines). This article provides a brief summary of the various aspects of the tool implemented, illustrated through a few examples drawn from the studies referred to above. (authors)

  18. Influence of the Determination Methods of K and C Parameters on the Ability of Weibull Distribution to Suitably Estimate Wind Potential and Electric Energy

    Directory of Open Access Journals (Sweden)

    Ruben M. Mouangue

    2014-05-01

    Full Text Available The modeling of the wind speed distribution is of great importance for the assessment of wind energy potential and the performance of wind energy conversion system. In this paper, the choice of two determination methods of Weibull parameters shows theirs influences on the Weibull distribution performances. Because of important calm winds on the site of Ngaoundere airport, we characterize the wind potential using the approach of Weibull distribution with parameters which are determined by the modified maximum likelihood method. This approach is compared to the Weibull distribution with parameters which are determined by the maximum likelihood method and the hybrid distribution which is recommended for wind potential assessment of sites having nonzero probability of calm. Using data provided by the ASECNA Weather Service (Agency for the Safety of Air Navigation in Africa and Madagascar, we evaluate the goodness of fit of the various fitted distributions to the wind speed data using the Q – Q plots, the Pearson’s coefficient of correlation, the mean wind speed, the mean square error, the energy density and its relative error. It appears from the results that the accuracy of the Weibull distribution with parameters which are determined by the modified maximum likelihood method is higher than others. Then, this approach is used to estimate the monthly and annual energy productions of the site of the Ngaoundere airport. The most energy contribution is made in March with 255.7 MWh. It also appears from the results that a wind turbine generator installed on this particular site could not work for at least a half of the time because of higher frequency of calm. For this kind of sites, the modified maximum likelihood method proposed by Seguro and Lambert in 2000 is one of the best methods which can be used to determinate the Weibull parameters.

  19. The development of crack measurement system using the direct current potential drop method for use in the hot cell

    International Nuclear Information System (INIS)

    Kim, Do-Sik; Ahn, Sang-Bok; Lee, Key-Soon; Kim, Yong-Suk; Kwon, Sang-Chul

    1999-01-01

    The crack length measurement system using the direct current potential drop (DCPD) method was developed for the detection of crack growth initiation and subsequent crack growth. The experimental precautions and data processing procedure required for its application were also described find discussed. The system presented herein was specially built for use in fracture toughness testing of unirradiated or irradiated pressure tube materials from nuclear reactor. The application of this system for fracture toughness determination was illustrated from the test of curved compact tension specimens removed from CANDU reactor pressure tubes. The crack extension was monitored using the DCPD method. It is found that the changes of the potential drop and the changes of the crack length have a linear relationship. The final crack front was marked by heat-tinting after the test and the specimen broken open for determination of the initial and final physical crack length. The physical crack lengths, obtained by the 9-point average method described in ASTM E1737-96 on heat-tinted fracture surface, were used to calibrate the DCPD method for each test on an individual basis by matching the change in voltage to the crack extension. It is found that this system can be recommended for determination of the J-integral resistance (J-R) curve of unirradiated or irradiation materials in the hot cell, especially when testing at elevated temperature and in the environment chamber or furnace. (author)

  20. Strategies for Solving Potential Problems Associated with Laboratory Diffusion and Batch Experiments - Part 1: An Overview of Conventional Test Methods

    International Nuclear Information System (INIS)

    Zhang, M.; Takeda, M.; Nakajima, H.

    2006-01-01

    Laboratory diffusion testing as well as batch experiments are well established and widely adopted techniques for characterizing the diffusive and adsorptive properties