Sample records for relevant experimental studies

  1. Scale-up considerations relevant to experimental studies of nuclear waste-package behavior

    Coles, D.G.; Peters, R.D.


    Results from a study that investigated whether testing large-scale nuclear waste-package assemblages was technically warranted are reported. It was recognized that the majority of the investigations for predicting waste-package performance to date have relied primarily on laboratory-scale experimentation. However, methods for the successful extrapolation of the results from such experiments, both geometrically and over time, to actual repository conditions have not been well defined. Because a well-developed scaling technology exists in the chemical-engineering discipline, it was presupposed that much of this technology could be applicable to the prediction of waste-package performance. A review of existing literature documented numerous examples where a consideration of scaling technology was important. It was concluded that much of the existing scale-up technology is applicable to the prediction of waste-package performance for both size and time extrapolations and that conducting scale-up studies may be technically merited. However, the applicability for investigating the complex chemical interactions needs further development. It was recognized that the complexity of the system, and the long time periods involved, renders a completely theoretical approach to performance prediction almost hopeless. However, a theoretical and experimental study was defined for investigating heat and fluid flow. It was concluded that conducting scale-up modeling and experimentation for waste-package performance predictions is possible using existing technology. A sequential series of scaling studies, both theoretical and experimental, will be required to formulate size and time extrapolations of waste-package performance.

  2. An experimental and theoretical study of reaction steps relevant to the methanol-to-hydrocarbons reaction

    Svelle, Stian


    The primary objective of the present work is to obtain new insight into the reaction mechanism of the zeolite catalyzed methanol-to-hydrocarbons (MTH) reaction. It was decided to use both experimental and computational techniques to reach this goal. An investigation of the n-butene + methanol system was therefore initiated. Over time, it became apparent that it was possible to determine the rate for the methylation of n-butene by methanol. The ethene and propene systems were therefore reexamined in order to collect kinetic information also for those cases. With the development of user-friendly quantum chemistry programs such as the Gaussian suite of programs, the possibility of applying quantum chemical methods to many types of problems has become readily available even for non-experts. When performing mechanistic studies, there is quite often a considerable synergy effect when combining experimental and computational approaches. The methylation reactions mentioned above turned out to be an issue well suited for quantum chemical investigations. The incentive for examining the halomethane reactivity was the clear analogy to the MTH reaction system. Alkene dimerization was also a reaction readily examined with quantum chemistry. As discussed in the introduction of this thesis, polymethylbenzenes, or their cationic counterparts, are suspected to be key intermediates in the MTH reaction. It was therefore decided to investigate the intrinsic reactivity of these species in the gas-phase by employing sophisticated mass spectrometric (MS) techniques in collaboration with the MS group at the Department of Chemistry, University of Oslo The data thus obtained will also be compared with results from an ongoing computational study on gas phase polymethylbenzenium reactivity. 6 papers presenting various studies are included. The titles are: 1) A Theoretical Investigation of the Methylation of Alkenes with Methanol over Acidic Zeolites. 2) A Theoretical Investigation of the

  3. Recent results from experimental studies on laser-plasma coupling in a shock ignition relevant regime

    Koester, P.; Antonelli, L.; Atzeni, S.; Badziak, J.; Baffigi, F.; Batani, D.; Cecchetti, C. A.; Chodukowski, T.; Consoli, F.; Cristoforetti, G.; De Angelis, R.; Folpini, G.; Gizzi, L. A.; Kalinowska, Z.; Krousky, E.; Kucharik, M.; Labate, L.; Levato, T.; Liska, R.; Malka, G.; Maheut, Y.; Marocchino, A.; Nicolai, P.; O'Dell, T.; Parys, P.; Pisarczyk, T.; Raczka, P.; Renner, O.; Rhee, Y. J.; Ribeyre, X.; Richetta, M.; Rosinski, M.; Ryc, L.; Skala, J.; Schiavi, A.; Schurtz, G.; Smid, M.; Spindloe, C.; Ullschmied, J.; Wolowski, J.; Zaras, A.


    Shock ignition (SI) is an appealing approach in the inertial confinement scenario for the ignition and burn of a pre-compressed fusion pellet. In this scheme, a strong converging shock is launched by laser irradiation at an intensity Iλ2 > 1015 W cm-2 µm2 at the end of the compression phase. In this intensity regime, laser-plasma interactions are characterized by the onset of a variety of instabilities, including stimulated Raman scattering, Brillouin scattering and the two plasmon decay, accompanied by the generation of a population of fast electrons. The effect of the fast electrons on the efficiency of the shock wave production is investigated in a series of dedicated experiments at the Prague Asterix Laser Facility (PALS). We study the laser-plasma coupling in a SI relevant regime in a planar geometry by creating an extended preformed plasma with a laser beam at ˜7 × 1013 W cm-2 (250 ps, 1315 nm). A strong shock is launched by irradiation with a second laser beam at intensities in the range 1015-1016 W cm-2 (250 ps, 438 nm) at various delays with respect to the first beam. The pre-plasma is characterized using x-ray spectroscopy, ion diagnostics and interferometry. Spectroscopy and calorimetry of the backscattered radiation is performed in the spectral range 250-850 nm, including (3/2)ω, ω and ω/2 emission. The fast electron production is characterized through spectroscopy and imaging of the Kα emission. Information on the shock pressure is obtained using shock breakout chronometry and measurements of the craters produced by the shock in a massive target. Preliminary results show that the backscattered energy is in the range 3-15%, mainly due to backscattered light at the laser wavelength (438 nm), which increases with increasing the delay between the two laser beams. The values of the peak shock pressures inferred from the shock breakout times are lower than expected from 2D numerical simulations. The same simulations reveal that the 2D effects play a

  4. Benchmark Thermochemistry for Biologically Relevant Adenine and Cytosine. A Combined Experimental and Theoretical Study.

    Emel'yanenko, Vladimir N; Zaitsau, Dzmitry H; Shoifet, Evgeni; Meurer, Florian; Verevkin, Sergey P; Schick, Christoph; Held, Christoph


    The thermochemical properties available in the literature for adenine and cytosine are in disarray. A new condensed phase standard (p° = 0.1 MPa) molar enthalpy of formation at T = 298.15 K was measured by using combustion calorimetry. New molar enthalpies of sublimation were derived from the temperature dependence of vapor pressure measured by transpiration and by the quarz-crystal microbalance technique. The heat capacities of crystalline adenine and cytosine were measured by temperature-modulated DSC. Thermodynamic data on adenine and cytosine available in the literature were collected, evaluated, and combined with our experimental results. Thus, the evaluated collection of data together with the new experimental results reported here has helped to resolve contradictions in the available enthalpies of formation. A set of reliable thermochemical data is recommended for adenine and cytosine for further thermochemical calculations. Quantum-chemical calculations of the gas phase molar enthalpies of formation of adenine and cytosine have been performed by using the G4 method and results were in excellent agreement with the recommended experimental data. The standard molar entropies of formation and the standard molar Gibbs functions of formation in crystal and gas state have been calculated. Experimental vapor-pressure data measured in this work were used to estimate pure-component PC-SAFT parameters. This allowed modeling solubility of adenine and cytosine in water over the temperature interval 278-310 K.

  5. Experimental Study of Water Cluster Molecules with Relevance to Mesospheric Clouds

    Robertson, Scott; Sternovsky, Zoltan; Horanyi, Mihaly


    We have begun an experimental investigation of the properties of the water cluster molecules responsible for clouds occurring in the polar mesopause. These clusters disturb the charge balance in the ionosphere by attaching electrons which then creates localized reductions in the electron density. A supersonic nozzle sprays a mixture of water vapor and argon into vacuum and the expansion leads to condensation of clusters with 4 to 11 water molecules. Initial measurements are of the collision cross section of these molecules with neutral gas. The cross sections have a minimum at six waters consistent with the tighter molecular arrangement predicted for this cluster number. Additional measurements are underway for charging processes.

  6. 16 CFR 1702.9 - Relevant experimental data.


    ... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Relevant experimental data. 1702.9 Section... AND REQUIREMENTS § 1702.9 Relevant experimental data. Experimental data are generated in both animals.... Therefore, the Commission considers experimental data obtained in animal studies to be an...

  7. The relevance of a rules-based maize marketing policy: an experimental case study of Zambia.

    Abbink, Klaus; Jayne, Thomas S; Moller, Lars C


    Strategic interaction between public and private actors is increasingly recognised as an important determinant of agricultural market performance in Africa and elsewhere. Trust and consultation tends to positively affect private activity while uncertainty of government behaviour impedes it. This paper reports on a laboratory experiment based on a stylised model of the Zambian maize market. The experiment facilitates a comparison between discretionary interventionism and a rules-based policy in which the government pre-commits itself to a future course of action. A simple precommitment rule can, in theory, overcome the prevailing strategic dilemma by encouraging private sector participation. Although this result is also borne out in the economic experiment, the improvement in private sector activity is surprisingly small and not statistically significant due to irrationally cautious choices by experimental governments. Encouragingly, a rules-based policy promotes a much more stable market outcome thereby substantially reducing the risk of severe food shortages. These results underscore the importance of predictable and transparent rules for the state's involvement in agricultural markets.

  8. Combining experimental and computational studies to understand and predict reactivities of relevance to homogeneous catalysis.

    Tsang, Althea S-K; Sanhueza, Italo A; Schoenebeck, Franziska


    This article showcases three major uses of computational chemistry in reactivity studies: the application after, in combination with, and before experiment. Following a brief introduction of suitable computational tools, challenges and opportunities in the implementation of computational chemistry in reactivity studies are discussed, exemplified with selected case studies from our and other laboratories.

  9. Experimental Animal Models of Pancreatic Carcinogenesis for Prevention Studies and Their Relevance to Human Disease

    Hitoshi Nakagama


    Full Text Available Pancreatic cancer is difficult to cure, so its prevention is very important. For this purpose, animal model studies are necessary to develop effective methods. Injection of N-nitrosobis(2-oxopropylamine (BOP into Syrian golden hamsters is known to induce pancreatic ductal adenocarcinomas, the histology of which is similar to human tumors. Moreover, K-ras activation by point mutations and p16 inactivation by aberrant methylation of 5’ CpG islands or by homozygous deletions have been frequently observed in common in both the hamster and humans. Thus, this chemical carcinogenesis model has an advantage of histopathological and genetic similarity to human pancreatic cancer, and it is useful to study promotive and suppressive factors. Syrian golden hamsters are in a hyperlipidemic state even under normal dietary conditions, and a ligand of peroxizome proliferator-activated receptor gamma was found to improve the hyperlipidemia and suppress pancreatic carcinogenesis. Chronic inflammation is a known important risk factor, and selective inhibitors of inducible nitric oxide synthase and cyclooxygenase-2 also have protective effects against pancreatic cancer development. Anti-inflammatory and anti-hyperlipidemic agents can thus be considered candidate chemopreventive agents deserving more attention.

  10. Experimental Animal Models of Pancreatic Carcinogenesis for Prevention Studies and Their Relevance to Human Disease

    Takahashi, Mami, E-mail:; Hori, Mika; Mutoh, Michihiro [Division of Cancer Development System, Carcinogenesis Research Group, National Cancer Center Research Institute, 1-1, Tsukiji 5-chome, Chuo-ku, Tokyo 104-0045 (Japan); Wakabayashi, Keiji [Graduate School of Nutritional and Environmental Sciences, University of Shizuoka, Yada 52-1, Suruga-ku, Shizuoka 422-8526 (Japan); Nakagama, Hitoshi [Division of Cancer Development System, Carcinogenesis Research Group, National Cancer Center Research Institute, 1-1, Tsukiji 5-chome, Chuo-ku, Tokyo 104-0045 (Japan)


    Pancreatic cancer is difficult to cure, so its prevention is very important. For this purpose, animal model studies are necessary to develop effective methods. Injection of N-nitrosobis(2-oxopropyl)amine (BOP) into Syrian golden hamsters is known to induce pancreatic ductal adenocarcinomas, the histology of which is similar to human tumors. Moreover, K-ras activation by point mutations and p16 inactivation by aberrant methylation of 5′ CpG islands or by homozygous deletions have been frequently observed in common in both the hamster and humans. Thus, this chemical carcinogenesis model has an advantage of histopathological and genetic similarity to human pancreatic cancer, and it is useful to study promotive and suppressive factors. Syrian golden hamsters are in a hyperlipidemic state even under normal dietary conditions, and a ligand of peroxizome proliferator-activated receptor gamma was found to improve the hyperlipidemia and suppress pancreatic carcinogenesis. Chronic inflammation is a known important risk factor, and selective inhibitors of inducible nitric oxide synthase and cyclooxygenase-2 also have protective effects against pancreatic cancer development. Anti-inflammatory and anti-hyperlipidemic agents can thus be considered candidate chemopreventive agents deserving more attention.

  11. Relevance of workplace social mixing during influenza pandemics: an experimental modelling study of workplace cultures.

    Timpka, T; Eriksson, H; Holm, E; Strömgren, M; Ekberg, J; Spreco, A; Dahlström, Ö


    Workplaces are one of the most important regular meeting places in society. The aim of this study was to use simulation experiments to examine the impact of different workplace cultures on influenza dissemination during pandemics. The impact is investigated by experiments with defined social-mixing patterns at workplaces using semi-virtual models based on authentic sociodemographic and geographical data from a North European community (population 136 000). A simulated pandemic outbreak was found to affect 33% of the total population in the community with the reference academic-creative workplace culture; virus transmission at the workplace accounted for 10·6% of the cases. A model with a prevailing industrial-administrative workplace culture generated 11% lower incidence than the reference model, while the model with a self-employed workplace culture (also corresponding to a hypothetical scenario with all workplaces closed) produced 20% fewer cases. The model representing an academic-creative workplace culture with restricted workplace interaction generated 12% lower cumulative incidence compared to the reference model. The results display important theoretical associations between workplace social-mixing cultures and community-level incidence rates during influenza pandemics. Social interaction patterns at workplaces should be taken into consideration when analysing virus transmission patterns during influenza pandemics.

  12. Experimental studies of keV energy neutron-induced reactions relevant to astrophysics and nuclear physics

    Shima, T.; Kii, T.; Kikuchi, T.; Okazaki, F.; Kobayashi, T.; Baba, T.; Nagai, Y. [Tokyo Inst. of Tech. (Japan). Faculty of Science; Igashira, M.


    Nuclear reactions induced by keV energy neutrons provide a plenty of informations for studies of both astrophysics and nuclear physics. In this paper we will show our experimental studies of neutron- induced reactions of light nuclei in the keV energy region by means of a pulsed keV neutron beam and high-sensitivity detectors. Also we will discuss astrophysical and nuclear-physical consequences by using the obtained results. (author)

  13. A combined experimental and theoretical study of reactions between the hydroxyl radical and oxygenated hydrocarbons relevant to astrochemical environments.

    Shannon, R J; Caravan, R L; Blitz, M A; Heard, D E


    The kinetics of the reactions of the hydroxyl radical (OH) with acetone and dimethyl ether (DME) have been studied between 63-148 K and at a range of pressures using laser-flash photolysis coupled with laser induced fluorescence detection of OH in a pulsed Laval nozzle apparatus. For acetone, a large negative temperature dependence was observed, with the rate coefficient increasing from k1 = (1.6 ± 0.8) × 10(-12) cm(3) molecule(-1) s(-1) at 148 K to (1.0 ± 0.1) × 10(-10) cm(3) molecule(-1) s(-1) at 79 K, and also increasing with pressure. For DME, a similar behaviour was found, with the rate coefficient increasing from k2 = (3.1 ± 0.5) × 10(-12) cm(3) molecule(-1) s(-1) at 138 K to (1.7 ± 0.1) × 10(-11) cm(3) molecule(-1) s(-1) at 63 K, and also increasing with pressure. The temperature and pressure dependence of the experimental rate coefficients are rationalised for both reactions by the formation and subsequent stabilisation of a hydrogen bonded complex, with a non-zero rate coefficient extrapolated to zero pressure supportive of quantum mechanical tunnelling on the timescale of the experiments leading to products. In the case of DME, experiments performed in the presence of O2 provide additional evidence that the yield of the CH3OCH2 abstraction product, which can recycle OH in the presence of O2, is ≥50%. The experimental data are modelled using the MESMER (Master Equation Solver for Multi Energy Well Reactions) code which includes a treatment of quantum mechanical tunnelling, and uses energies and structures of transition states and complexes calculated by ab initio methods. Good agreement is seen between experiment and theory, with MESMER being able to reproduce for both reactions the temperature behaviour between ~70-800 K and the pressure dependence observed at ~80 K. At the limit of zero pressure, the model predicts a rate coefficient of ~10(-11) cm(3) molecule(-1) s(-1) for the reaction of OH with acetone at 20 K, providing evidence that the

  14. Experimental Studies of Selected Aqueous Electrochemical Systems Relevant for Materials Processing in the Fabrications of Microelectronic Components and Direct Alcohol Fuel Cells

    Shi, Xingzhao

    A broad range of electrochemical techniques are employed in this dissertation to investigate a selected set of aqueous electrochemical systems that are relevant for materials processing in the fabrication of microelectronic devices and direct alcohol fuel cells. In terms of technical applications, this work covers three main experimental systems: (i) chemical mechanical planarization (CMP), (ii) electro-less nickel deposition, and (iii) direct alkaline glycerol fuel cells. The first two areas are related to electronic device fabrications and the third topic is related to cost-effective energy conversion. The common electrochemical aspect of these different systems is that, in all these cases the active material characteristics are governed by complex (often multi-step) reactions occurring at metal-liquid (aqueous) interfaces. Electro-analytical techniques are ideally suited for studying the detailed mechanisms of such reactions, and the present investigation is largely focused on developing adequate analytical strategies for probing these reaction mechanisms. In the fabrication of integrated circuits, certain steps of materials processing involve CMP of Al deposited on thin layers of diffusion barrier materials like Ta/TaN, Co, or Ti/TiN. A specific example of this situation is found in the processing of replacement metal gates used for high-k/metal-gate transistors. Since the commonly used barrier materials are nobler than Al, the Al interface in contact with the barrier can become prone to galvanic corrosion in the wet CMP environment. Using model systems of coupon electrodes and two specific barrier metals, Ta and Co, the electrochemical factors responsible for these corrosion effects are investigated here in a moderately acidic (pH = 4.0) abrasive-free solution. The techniques of cyclic voltammetry and impedance spectroscopy are combined with strategic measurements of galvanic currents and open circuit potentials (OCPs). L-ascorbic acid (AA) is employed as a

  15. Physiological relevance and performance of a minimal lung model – an experimental study in healthy and acute respiratory distress syndrome model piglets

    Chiew Yeong


    Full Text Available Abstract Background Mechanical ventilation (MV is the primary form of support for acute respiratory distress syndrome (ARDS patients. However, intra- and inter- patient-variability reduce the efficacy of general protocols. Model-based approaches to guide MV can be patient-specific. A physiological relevant minimal model and its patient-specific performance are tested to see if it meets this objective above. Methods Healthy anesthetized piglets weighing 24.0 kg [IQR: 21.0-29.6] underwent a step-wise PEEP increase manoeuvre from 5cmH2O to 20cmH2O. They were ventilated under volume control using Engström Care Station (Datex, General Electric, Finland, with pressure, flow and volume profiles recorded. ARDS was then induced using oleic acid. The data were analyzed with a Minimal Model that identifies patient-specific mean threshold opening and closing pressure (TOP and TCP, and standard deviation (SD of these TOP and TCP distributions. The trial and use of data were approved by the Ethics Committee of the Medical Faculty of the University of Liege, Belgium. Results and discussions 3 of the 9 healthy piglets developed ARDS, and these data sets were included in this study. Model fitting error during inflation and deflation, in healthy or ARDS state is less than 5.0% across all subjects, indicating that the model captures the fundamental lung mechanics during PEEP increase. Mean TOP was 42.4cmH2O [IQR: 38.2-44.6] at PEEP = 5cmH2O and decreased with PEEP to 25.0cmH2O [IQR: 21.5-27.1] at PEEP = 20cmH2O. In contrast, TCP sees a reverse trend, increasing from 10.2cmH2O [IQR: 9.0-10.4] to 19.5cmH2O [IQR: 19.0-19.7]. Mean TOP increased from average 21.2-37.4cmH2O to 30.4-55.2cmH2O between healthy and ARDS subjects, reflecting the higher pressure required to recruit collapsed alveoli. Mean TCP was effectively unchanged. Conclusion The minimal model is capable of capturing physiologically relevant TOP, TCP and SD of both healthy and ARDS lungs. The

  16. The Personal Relevance of the Social Studies.

    VanSickle, Ronald L.


    Conceptualizes a personal-relevance framework derived from Ronald L. VanSickle's five areas of life integrated with four general motivating goals from Abraham Maslow's hierarchy of needs and Richard and Patricia Schmuck's social motivation theory. Illustrates ways to apply the personal relevance framework to make social studies more relevant to…

  17. The Personal Relevance of the Social Studies.

    VanSickle, Ronald L.


    Conceptualizes a personal-relevance framework derived from Ronald L. VanSickle's five areas of life integrated with four general motivating goals from Abraham Maslow's hierarchy of needs and Richard and Patricia Schmuck's social motivation theory. Illustrates ways to apply the personal relevance framework to make social studies more relevant to…

  18. Experimental study of clay-hydrocarbon interactions relevant to the biodegradation of the Deepwater Horizon oil from the Gulf of Mexico.

    Warr, Laurence N; Friese, André; Schwarz, Florian; Schauer, Frieder; Portier, Ralph J; Basirico, Laura M; Olson, Gregory M


    Adding clay to marine oil pollution represents a promising approach to enhance bacterial hydrocarbon degradation in nutrient poor waters. In this study, three types of regionally available clays (Ca-bentonite, Fuller's Earth and kaolin) were tested to stimulate the biodegradation of source and weathered oil collected from the Deepwater Horizon spill. The weathered oil showed little biodegradation prior to experimentation and was extensively degraded by bacteria in the laboratory in a similar way as the alkane-rich source oil. For both oils, the addition of natural clay-flakes showed minor enhancement of oil biodegradation compared to the non-clay bearing control, but the clay-oil films did limit evaporation. Only alkanes of a molecular weight (MW) > 420 showed significant reduction by enhanced biodegradation following natural clay treatment. In contrast, all fertilized clay flakes showed major bacterial degradation of the oil, with a 6-10 times reduction in alkane content, and an up to 8 fold increase in the rate of O2 consumption. Compared to the control, such treatment showed particular reduction of longer chained alkanes (MW > 226). The application of natural and fertilized clay flakes also showed selective reduction of PAHs, mainly in the MW range of 200-300, but without significant change in the toxicity indices measured. These results imply that a large variety of clays may be used to boost oil biodegradation by aiding attachment of fertilizing nutrients to the oil.

  19. An Experimental Study of Single Suspended H2so4/nh3/h2o-aerosols : Atmospheric Relevance of Letovicite

    Colberg, C. A.; Krieger, U. K.; Luo, B.; Wernli, H.; Peter, Th.

    Aerosols in the atmosphere have a large effect on the radiative balance of the earth due to their scattering and absorbing properties. Some aerosols can also act as cloud con- densation nuclei (CCN) of cirrus clouds which play an important role for the global climate. The influence of NH3 and H2SO4 containing aerosols on cirrus formation are discussed. The thermodynamic and kinetic behavior of the H2SO4/NH3/H2O-system at atmospheric conditions is poorly understood. The reason for this uncertainty is that thermodynamic models are mainly based on experimental data obtained at room tem- perature and that the conditions at which aerosols crystallize cannot be predicted re- liably. Hence, laboratory experiments are needed to improve our knowledge of the chemical and physical state of inorganic aerosols in the atmosphere. In the present work laboratory measurements of individual H2SO4/NH3/H2O-aerosols in an electrodynamic particle trap are performed. The trap is located in a thermally in- sulated chamber where the relative humidity (RH), the total pressure and temperature are controlled. The DC-Voltage is used as a direct measure for the mass of the parti- cles. The radii of liquid droplets are determined by Mie-phase-function-analysis and RMS-deviation measurements of the intensity fluctuations provide information on the aerosol morphology. Raman-spectroscopy is used to identify liquid and solid parti- cles chemically. These four analytical tools provide independent information on the aerosol composition and structure. The thermodynamic behavior of single suspended particles is examined for different stoichiometries at different temperatures and relative humidities. The deliquescence and efflorescence relative humidities (DRH and ERH), as well as the water uptake and loss are studied. In general the thermodynamic data of the present work is in good agreement to the model with Clegg et al. [1998] and existing experimental data. The observed solid phases are, surprisingly

  20. Synthesis, spectroscopic characterization and crystallographic behavior of a biologically relevant novel indole-fused heterocyclic compound - Experimental and theoretical (DFT) studies

    Sharma, Sakshi; Brahmachari, Goutam; Banerjee, Bubun; Nurjamal, Khondekar; Kumar, Abhishek; Srivastava, Ambrish Kumar; Misra, Neeraj; Pandey, Sarvesh Kumar; Rajnikant; Gupta, Vivek K.


    The present communication deals with the eco-friendly synthesis, spectral properties and X-ray crystal structure of an indole derivative - Ethyl 2'-amino-3'-cyano-6'-methyl-5-nitro-2-oxospiro [indoline-3,4'-pyran]-5'-carboxylate. The title compound was synthesized in 87% yield. The crystal structure of the molecule is stabilized by intermolecular Nsbnd H … N, Nsbnd H … O and Csbnd H … π interactions. The molecule is organized in the crystal lattice forming sheet like structure. To interpret the experimental data, ab initio computations of the vibrational frequencies were carried out using the Gaussian 09 program followed by the full optimizations done using Density Functional Theory (DFT) at B3LYP/6-31 + G(d,p) level. The combined use of experiments and computations allowed a firm assignment of the majority of observed bands for the compound. The calculated highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) with frontier orbital gap were presented. The electronic and charge transfer properties have been explained on the basis of highest occupied molecular orbitals (HOMOs), lowest unoccupied molecular orbitals (LUMOs) and density of states (DOS). From the optimized geometry of the molecule, molecular electrostatic potential (MEP) distribution, frontier molecular orbitals (FMOs) of the title compound have been calculated in the ground state theoretically. The theoretical results showed good agreement with the experimental values. First hyperpolarizability values have been calculated to describe the nonlinear optical (NLO) property of the synthesized compound.

  1. On the relevance of the H2 + O reaction pathway for the surface formation of interstellar water - A combined experimental and modeling study

    Lamberts, Thanja; Fedoseev, Gleb; Ioppolo, Sergio; Chuang, Ko-Ju; Linnartz, Harold


    The formation of interstellar water has been commonly accepted to occur on the surfaces of icy dust grains in dark molecular clouds at low temperatures (10-20 K), involving hydrogenation reactions of oxygen allotropes. As a result of the large abundances of molecular hydrogen and atomic oxygen in these regions, the reaction H2 + O has been proposed to contribute significantly to the formation of water as well. However, gas phase experiments and calculations, as well as solid-phase experimental work contradict this hypothesis. Here, we use precisely executed temperature programmed desorption (TPD) experiments in an ultra-high vacuum setup combined with kinetic Monte Carlo simulations to establish an upper limit of the water production starting from H2 and O. These reactants are brought together in a matrix of CO2 in a series of (control) experiments at different temperatures and with different isotopological compositions. The amount of water detected with the quadrupole mass spectrometer upon TPD is found to o...

  2. Studies on Relevance, Ranking and Results Display

    Gelernter, Judith; Carbonell, Jaime


    This study considers the extent to which users with the same query agree as to what is relevant, and how what is considered relevant may translate into a retrieval algorithm and results display. To combine user perceptions of relevance with algorithm rank and to present results, we created a prototype digital library of scholarly literature. We confine studies to one population of scientists (paleontologists), one domain of scholarly scientific articles (paleo-related), and a prototype system (PaleoLit) that we built for the purpose. Based on the principle that users do not pre-suppose answers to a given query but that they will recognize what they want when they see it, our system uses a rules-based algorithm to cluster results into fuzzy categories with three relevance levels. Our system matches at least 1/3 of our participants' relevancy ratings 87% of the time. Our subsequent usability study found that participants trusted our uncertainty labels but did not value our color-coded horizontal results layout ...

  3. Statistical evaluation of multiple-locus linkage data in experimental species and its relevance to human studies: Application to nonobese diabetic (NOD) mouse and human insulin-dependent diabetes mellitus (IDDM)

    Risch, N. (Yale Univ. School of Medicine, New Haven, CT (United States)); Ghosh, S.; Todd, J.A.


    Common, familial human disorders generally do not follow Mendelian inheritance patterns, presumably because multiple loci are involved in disease susceptibility. One approach to mapping genes for such traits in humans is to first study an analogous form in an animal model, such as mouse, by using inbred strains and backcross experiments. Here the authors describe methodology for analyzing multiple-locus linkage data from such experimental backcrosses, particularly in light of multilocus genetic models, including the effects of epistasis. They illustrate these methods by using data from backcrosses involving nonobese diabetic mouse, which serves as an animal model for human insulin-dependent diabetes mellitus. They show that it is likely that a minimum of nine loci contribute to susceptibility, with strong epistasis effects among these loci. Three of the loci actually confer a protective effect in the homozygote, compared with the heterozygote. Further, they discuss the relevance of these studies for analogous studies of the human form of the trait. Specifically, they show that the magnitude of the gene effect in the experimental backcross is likely to correlate only weakly, at best, with the expected magnitude of effect for a human form, because in humans the gene effect will depend more heavily on disease allele frequencies than on the observed penetrance ratios; such allele frequencies are unpredictable. Hence, the major benefit from animal studies may be a better understanding of the disease process itself, rather than identification of cells through comparison mapping in humans by using regions of homology. 12 refs., 7 tabs.

  4. Identifying Relevant Studies in Software Engineering

    Zhang, He; Ali Babar, Muhammad; Tell, Paolo


    Context: Systematic literature review (SLR) has become an important research methodology in software engineering since the introduction of evidence-based software engineering (EBSE) in 2004. One critical step in applying this methodology is to design and execute appropriate and effective search....... Objective: The main objective of the research reported in this paper is to improve the search step of undertaking SLRs in software engineering (SE) by devising and evaluating systematic and practical approaches to identifying relevant studies in SE. Method: We have systematically selected and analytically...

  5. Carryover negligibility and relevance in bioequivalence studies.

    Ocaña, Jordi; Sanchez O, Maria P; Carrasco, Josep L


    The carryover effect is a recurring issue in the pharmaceutical field. It may strongly influence the final outcome of an average bioequivalence study. Testing a null hypothesis of zero carryover is useless: not rejecting it does not guarantee the non-existence of carryover, and rejecting it is not informative of the true degree of carryover and its influence on the validity of the final outcome of the bioequivalence study. We propose a more consistent approach: even if some carryover is present, is it enough to seriously distort the study conclusions or is it negligible? This is the central aim of this paper, which focuses on average bioequivalence studies based on 2 × 2 crossover designs and on the main problem associated with carryover: type I error inflation. We propose an equivalence testing approach to these questions and suggest reasonable negligibility or relevance limits for carryover. Finally, we illustrate this approach on some real datasets.

  6. Review of relevant studies of isolated systems

    Hansen, L.H.; Lundsager, P.


    The report presents the results of a review of studies relating to integration of wind energy in isolated power supply systems, based on a systematic literature survey. The purpose of the study is to develop a methodology consisting of a set of guidelinesfor wind energy projects in isolated energy...... systems and a set of tools and models that are operational on an engineering level. The review is based on a literature search in the ETDE Energy Database with a main search covering the period 7/88 to 6/97 andsupplemented by partial update periods. A few newer references have been included in the review......, most notably the IEC/PAS 62111 specification. The amount of wind energy literature related to the subject is excessively large, and a complete review inwhich every relevant abstract is identified and examined is not feasible within the framework of this (or probably any other) study. The review results...

  7. Long Pentraxin 3: Experimental and Clinical Relevance in Cardiovascular Diseases

    Fabrizia Bonacina


    Full Text Available Pentraxin 3 (PTX3 is an essential component of the humoral arm of innate immunity and belongs, together with the C-reactive protein (CRP and other acute phase proteins, to the pentraxins' superfamily: soluble, multifunctional, pattern recognition proteins. Pentraxins share a common C-terminal pentraxin domain, which in the case of PTX3 is coupled to an unrelated long N-terminal domain. PTX3 in humans, like CRP, correlates with surrogate markers of atherosclerosis and is independently associated with the risk of developing vascular events. Studies addressing the potential physiopathological role of CRP in the cardiovascular system were so far inconclusive and have been limited by the fact that the sequence and regulation have not been conserved during evolution between mouse and man. On the contrary, the conservation of sequence, gene organization, and regulation of PTX3 supports the translation of animal model findings in humans. While PTX3 deficiency is associated with increased inflammation, cardiac damage, and atherosclerosis, the overexpression limits carotid restenosis after angioplasty. These observations point to a cardiovascular protective effect of PTX3 potentially associated with the ability of tuning inflammation and favor the hypothesis that the increased levels of PTX3 in subjects with cardiovascular diseases may reflect a protective physiological mechanism, which correlates with the immunoinflammatory response observed in several cardiovascular disorders.




    The article provides an overview of experimental studies of charoite and charoite-containing rock formation hypotheses. The authors conducted experiments to clarify charoite and host rocks interaction and study charoite transformation processes at high temperatures. A series of experiments was aimed at improving the substandard charoite samples. The experiments show the formation of polymineral reaction zones due to the contact interaction between charoite and microcline-arfvedsonite lamproph...

  9. Creation of reliable relevance judgments in information retrieval systems evaluation experimentation through crowdsourcing: a review.

    Samimi, Parnia; Ravana, Sri Devi


    Test collection is used to evaluate the information retrieval systems in laboratory-based evaluation experimentation. In a classic setting, generating relevance judgments involves human assessors and is a costly and time consuming task. Researchers and practitioners are still being challenged in performing reliable and low-cost evaluation of retrieval systems. Crowdsourcing as a novel method of data acquisition is broadly used in many research fields. It has been proven that crowdsourcing is an inexpensive and quick solution as well as a reliable alternative for creating relevance judgments. One of the crowdsourcing applications in IR is to judge relevancy of query document pair. In order to have a successful crowdsourcing experiment, the relevance judgment tasks should be designed precisely to emphasize quality control. This paper is intended to explore different factors that have an influence on the accuracy of relevance judgments accomplished by workers and how to intensify the reliability of judgments in crowdsourcing experiment.

  10. A Study on Translation Process Based on Relevance Theory



    Relevance theory belongs to the field of pragmatics. Translation is a kind of communicative activity in nature. In the frame of relevance theory, translation is the process of cognition and inference. This paper focuses on the study of trans-lation process on the basis of relevance theory in order to improve the practice of translation.

  11. A Study on Translation Process Based on Relevance TheoryA Study on Translation Process Based on Relevance Theory



    Relevance theory belongs to the field of pragmatics. Translation is a kind of communicative activity in nature. In the frame of relevance theory, translation is the process of cognition and inference. This paper focuses on the study of translation process on the basis of relevance theory in order to improve the practice of translation.

  12. Group theories: relevance to group safety studies.

    Benevento, A L


    Promoting safety in the workplace has been attempted in a variety of ways. Increasingly, industries are using groups such as safety teams and quality circles to promote worker safety. Group influences on individual behavior and attitudes have long been studied in the social psychology literature, but the theories have not been commonly found outside the psychology arena. This paper describes the group theories of group polarization, risky shift, social loafing, groupthink and team think and attempts to apply these theories to existing studies that examine work group influences on safety. Interesting parallels were found but only one study examined group influences as their primary focus of research. Since groups are increasingly used for safety promotion, future research on safety that studies group influences with respect to current group theories is recommended.

  13. Carryover negligibility and relevance in bioequivalence studies

    Ocaña i Rebull, Jordi; Sánchez Olavarría, María Pilar; Carrasco Jordan, Josep Lluís


    The carryover effect is a recurring issue in the pharmaceutical field. It may strongly influence the final outcome of an average bioequivalence study. Testing a null hypothesis of zero carryover is useless: not rejecting it does not guarantee the non-existence of carryover, and rejecting it is not informative of the true degree of carryover and its influence on the validity of the final outcome of the bioequivalence study. We propose a more consistent approach: even if some carryover is prese...

  14. Measuring reinforcement learning and motivation constructs in experimental animals: relevance to the negative symptoms of schizophrenia.

    Markou, Athina; Salamone, John D; Bussey, Timothy J; Mar, Adam C; Brunner, Daniela; Gilmour, Gary; Balsam, Peter


    The present review article summarizes and expands upon the discussions that were initiated during a meeting of the Cognitive Neuroscience Treatment Research to Improve Cognition in Schizophrenia (CNTRICS; meeting. A major goal of the CNTRICS meeting was to identify experimental procedures and measures that can be used in laboratory animals to assess psychological constructs that are related to the psychopathology of schizophrenia. The issues discussed in this review reflect the deliberations of the Motivation Working Group of the CNTRICS meeting, which included most of the authors of this article as well as additional participants. After receiving task nominations from the general research community, this working group was asked to identify experimental procedures in laboratory animals that can assess aspects of reinforcement learning and motivation that may be relevant for research on the negative symptoms of schizophrenia, as well as other disorders characterized by deficits in reinforcement learning and motivation. The tasks described here that assess reinforcement learning are the Autoshaping Task, Probabilistic Reward Learning Tasks, and the Response Bias Probabilistic Reward Task. The tasks described here that assess motivation are Outcome Devaluation and Contingency Degradation Tasks and Effort-Based Tasks. In addition to describing such methods and procedures, the present article provides a working vocabulary for research and theory in this field, as well as an industry perspective about how such tasks may be used in drug discovery. It is hoped that this review can aid investigators who are conducting research in this complex area, promote translational studies by highlighting shared research goals and fostering a common vocabulary across basic and clinical fields, and facilitate the development of medications for the treatment of symptoms mediated by reinforcement learning and motivational deficits.

  15. Experimental studies o

    Mohammad Mohsen Sarafraz


    Full Text Available Experimental investigations on the influences of different contaminants to deionized water have been conducted under the sub-cooled flow boiling heat transfer inside the vertical annulus. Many experiments have been performed to investigate the influence of different operating parameters on the flow boiling heat transfer coefficient in the upward flow of contaminated water under the atmospheric pressure. The experimental apparatus provides the particular conditions to investigate the influence of heat flux (up to 132 kW/m2, flow rate (1.5–3.5 l/min, sub-cooling level (Max. 30 °C, and concentration of contaminants (1–5% by volume. According to the results, with increasing the heat flux and flow rate, the flow boiling heat transfer coefficient and rate of bubble formation significantly increase. Results also demonstrated that adding contaminants to the deionized water causes the flow boiling heat transfer coefficient to be deteriorated. Likewise, sub-cooling level may only influence on the onset of nucleate boiling and heat flux corresponding to beginning of nucleate boiling phenomenon which is called inception heat flux.

  16. An ERP Study on Self-Relevant Object Recognition

    Miyakoshi, Makoto; Nomura, Michio; Ohira, Hideki


    We performed an event-related potential study to investigate the self-relevance effect in object recognition. Three stimulus categories were prepared: SELF (participant's own objects), FAMILIAR (disposable and public objects, defined as objects with less-self-relevant familiarity), and UNFAMILIAR (others' objects). The participants' task was to…

  17. Topology of the interactions pattern in pharmaceutically relevant polymorphs of methylxanthines (caffeine, theobromine, and theophiline): combined experimental (¹H-¹⁴N nuclear quadrupole double resonance) and computational (DFT and Hirshfeld-based) study.

    Latosińska, Jolanta Natalia; Latosińska, Magdalena; Olejniczak, Grzegorz A; Seliger, Janez; Žagar, Veselko


    Three anhydrous methylxanthines: caffeine (1,3,7-trimethylxanthine; 1,3,7-trimethyl-1H-purine-2,6-(3H,7H)-dione) and its two metabolites theophylline (1,3-dimethylxanthine; 1,3-dimethyl-7H-purine-2,6-dione) and theobromine (3,7-dimethyl-xanthine; 3,7-dimethyl-7H-purine-2,6-dione), which reveal multifaceted therapeutic potential, have been studied experimentally in solid state by (1)H-(14)N NMR-NQR (nuclear magnetic resonance-nuclear quadrupole resonance) double resonance (NQDR). For each compound the complete NQR spectrum consisting of 12 lines was recorded. The multiplicity of NQR lines indicates the presence of a stable β form of anhydrous caffeine at 233 K and stable form II of anhydrous theobromine at 213 K. The assignment of signals detected in NQR experiment to particular nitrogen atoms was made on the basis of quantum chemistry calculations performed for monomer, cluster, and solid at the DFT/GGA/BLYP/DPD level. The shifts due to crystal packing interactions were evaluated, and the multiplets detected by NQR were assigned to N(9) in theobromine and N(1) and N(9) in caffeine. The ordering theobromine > theophylline > caffeine site and theophylline theobromine theobromine) to π···π stacking (caffeine). Substantial differences in the intermolecular interactions in stable forms of methylxanthines differing in methylation (site or number) were analyzed within the Hirshfeld surface-based approach. The analysis of local environment of the nitrogen nucleus permitted drawing some conclusions on the nature of the interactions required for effective processes of recognition and binding of a given methylxanthine to A1-A(2A) receptor (target for caffeine in the brain). Although the interactions responsible for linking neighboring methylxanthines molecules in crystals and methylxanthines with targets in the human organism can differ significantly, the knowledge of the topology of interactions provides reliable preliminary information about the nature of this binding.

  18. Experimental determination of creep properties of Beryllium irradiated to relevant fusion power reactor doses

    Scibetta, M.; Pellettieri, A.; Sannen, L.


    A dead weight machine has been developed to measure creep in irradiated beryllium relevant to fusion power reactors. Due to the external compressive load, the material will creep and the specimen will shrink. However, the specimen also swells due to the combined effect of internal pressure in helium bubbles and creep. One of the major challenges is to unmask swelling and derive intrinsic creep properties. This has been achieved through appropriate pre-annealing experiments. Creep has been measured on irradiated and unirradiated specimens. The temperature and stress dependence is characterized and modeled using the product of an Arrhenius' law for the temperature dependence and a power law for the stress dependence. Irradiation increases the sensitivity to creep but the irradiation effects can be rationalized by taking into account the irradiation-induced porosity. Experimental evidence supports dislocation climb by vacancy absorption to be the most plausible intrinsic creep mechanism.

  19. Studies relevant to the catalytic activation of carbon monoxide

    Ford, P.C.


    Research activity during the 1991--1992 funding period has been concerned with the following topics relevant to carbon monoxide activation. (1) Exploratory studies of water gas shift catalysts heterogenized on polystyrene based polymers. (2) Mechanistic investigation of the nucleophilic activation of CO in metal carbonyl clusters. (3) Application of fast reaction techniques to prepare and to investigate reactive organometallic intermediates relevant to the activation of hydrocarbons toward carbonylation and to the formation of carbon-carbon bonds via the migratory insertion of CO into metal alkyl bonds.

  20. Experimental Study on Hysucat Vessels

    M.S.Seif; M.Askari


    The paper contains the results of an experimental study on a planing catamaran. The aim of this study is resistance reduction with application of foils. Experiments are performed in different conditions and the results are compared with each other. The foils are used in different configurations and it is concluded that unsuitable design may result in larger resistance. But, it is also shown that, for a good design, the resistance may be reduced considerably.

  1. Experimental design applied to spin coating of 2D colloidal crystal masks: a relevant method?

    Colson, Pierre; Cloots, Rudi; Henrist, Catherine


    Monolayers of colloidal spheres are used as masks in nanosphere lithography (NSL) for the selective deposition of nanostructured layers. Several methods exist for the formation of self-organized particle monolayers, among which spin coating appears to be very promising. However, a spin coating process is defined by several parameters like several ramps, rotation speeds, and durations. All parameters influence the spreading and drying of the droplet containing the particles. Moreover, scientists are confronted with the formation of numerous defects in spin coated layers, limiting well-ordered areas to a few micrometers squared. So far, empiricism has mainly ruled the world of nanoparticle self-organization by spin coating, and much of the literature is experimentally based. Therefore, the development of experimental protocols to control the ordering of particles is a major goal for further progress in NSL. We applied experimental design to spin coating, to evaluate the efficiency of this method to extract and model the relationships between the experimental parameters and the degree of ordering in the particles monolayers. A set of experiments was generated by the MODDE software and applied to the spin coating of latex suspension (diameter 490 nm). We calculated the ordering by a homemade image analysis tool. The results of partial least squares (PLS) modeling show that the proposed mathematical model only fits data from strictly monolayers but is not predictive for new sets of parameters. We submitted the data to principal component analysis (PCA) that was able to explain 91% of the results when based on strictly monolayered samples. PCA shows that the ordering was positively correlated to the ramp time and negatively correlated to the first rotation speed. We obtain large defect-free domains with the best set of parameters tested in this study. This protocol leads to areas of 200 μm(2), which has never been reported so far.

  2. The relevance of analogue studies for understanding obsessions and compulsions.

    Abramowitz, Jonathan S; Fabricant, Laura E; Taylor, Steven; Deacon, Brett J; McKay, Dean; Storch, Eric A


    Analogue samples are often used to study obsessive-compulsive (OC) symptoms and related phenomena. This approach is based on the hypothesis that results derived from such samples are relevant to understanding OC symptoms in individuals with a diagnosis of obsessive-compulsive disorder (OCD). Two decades ago, Gibbs (1996) reviewed the available literature and found initial support for this hypothesis. Since then there have been many important advances addressing this issue. The purpose of the present review was to synthesize various lines of research examining the assumptions of using analogue samples to draw inferences about people with OCD. We reviewed research on the prevalence of OC symptoms in non-clinical populations, the dimensional (vs. categorical) nature of these symptoms, phenomenology, etiology, and studies on developmental and maintenance factors in clinical and analogue samples. We also considered the relevance of analogue samples in OCD treatment research. The available evidence suggests research with analogue samples is highly relevant for understanding OC symptoms. Guidelines for the appropriate use of analogue designs and samples are suggested.

  3. Experimental studies of antiprotonic helium

    Widmann, E


    This talk describes the experimental studies of metastable antiprotonic helium "atomcules" pHe/sup +/ (a neutral exotic atom consisting of a helium nucleus, an antiproton and an electron) performed at CERN-LEAR, and future plans for experiments at the forthcoming Antiproton Decelerator (AD) at CERN. Laser spectroscopy experiments are reviewed which led to the observation of a total of 13 resonant transitions of the antiproton in both p/sup 4/He/sup +/ and p/sup 3/He/sup +/, and revealed a hyperfine splitting in one transition. A level of precision has been reached where the most accurate 3-body calculations need to include QED effects like the Lamb-shift to come close to the experimental results. (52 refs).

  4. Experimental studies of glass refining

    Subramanian, R. S.; Cole, R.; Kondos, P.


    The basic components of the experimental apparatus were selected and acquired. Techniques were developed for the fabrication of the special crucibles necessary for the experiments. Arrangements were made for the analysis of glass and gas bubble samples for composition information. Donations of major equipment were received for this project from Owens, Illinois where a similar study had been conducted a few year ago. Decisions were made regarding the actual glass composition to be used, the gas to be used in the first experiments, and the temperatures at which the experiments should be conducted. A microcomputer was acquired, and work was begun on interfacing the video analyzer to it.

  5. [Experimental study of vestibular neurectomy].

    Pech, A; Cannoni, M; Appaix, M; Cahier, S; Lacour, M; Roll, J P


    The authors describe an experimental study carried out on baboons. After unilateral vestibular neurectomy, the behaviour disorders on the one hand, and on the other, modifications and temporal development of reflex muotatic excitability of the spine using Hoffmann's reflex method are analyzed. As far as behaviour is concerned, a four-day period of motor restriction following the operation causes more marked residual disorders in comparison with controls. From the neurophysiological point of view, neurectomy results in seriously disordered spinal reflexes characterized by ipsilateral hypo-excitability developing in there stages: a tw-day initial critical phase during which the disorders are at their worst, a four-day recuperative stage with partial regression of the disorders, finally a chronic compensation stage in which spinal excitability returns to normal after several months.

  6. Ideas for Hypertensive Experimental Study Prevented and Treated by TCM



    Hypertensive experimental studies prevented and treated by TCM are matured relevant studies of western medicine for reference, such as the hypotensive effect and elucidating its therapeutic mechanism. Comprehension in all literatures, most simple herbs and compound recipes show functions such as: Adjustment of renin-angiotensin-aldosterone system (RAAS), like angiotensin converting enzyme inhibitor (ACEI);

  7. Ideas for Hypertensive Experimental Study Prevented and Treated by TCM



    @@ Hypertensive experimental studies prevented and treated by TCM are matured relevant studies of western medicine for reference,such as the hypotensive effect and elucidating its therapeutic mechanism.Comprehension in all literatures, most simple herbs and compound recipes show functions such as: Adjustment of renin-angiotensin-aldosterone system (RAAS), like angiotensin converting enzyme inhibitor (ACEI);

  8. Experimental Studies on Electronic Portfolios in Turkey: A Literature Review

    Alan, Selahattin; Sünbül, Ali Murat


    In this study, a literature review was conducted about an individual's selected efforts, products stored in electronic format, and electronic portfolios that reflect the development and capacity of multimedia systems. In this context, relevant experimental studies performed in Turkey are collected to show e-portfolio application forms, their…

  9. Experimental and Numerical Models of Complex Clinical Scenarios; Strategies to Improve Relevance and Reproducibility of Joint Replacement Research.

    Bechtold, Joan E; Swider, Pascal; Goreham-Voss, Curtis; Soballe, Kjeld


    , material, and surgical features to influence implant-bone healing, using a selection of results from two decades of coordinated experimental and numerical work and (b) discuss limitations of such models and the implications for research reproducibility. Focusing model conditions toward the clinical scenario to be studied, and limiting conclusions to the conditions of a particular model can increase clinical relevance and research reproducibility.

  10. Experimental Work Conducted on MgO Inundated Hydration in WIPP-Relevant Brines

    Deng, H.; Xiong, Y.; Nemer, M. B.; Johnsen, S.


    Magnesium oxide (MgO) is being emplaced in the Waste Isolation Pilot Plant (WIPP) as an engineered barrier to mitigate the effect of microbial CO2 generation on actinide mobility in a postclosure repository environment. MgO will sequester CO2 and consume water in brine or water vapor in the gaseous phase. Martin Marietta (MM) MgO is currently being emplaced in the WIPP. A fractional-factorial experiment has been performed to study the inundated-hydration of MM MgO as a function of its particle size, solid-to-liquid ratio, and brine type. MgO hydration experiments have been carried out with three MgO particle sizes and two solid-to-liquid ratios in three WIPP-related brines: ERDA-6, GWB and simplified GWB. ERDA-6 is a synthetic NaCl-rich brine typical of a Castile brine reservoir below the repository. GWB is a synthetic MgCl2- and NaCl-rich brine representative of intergranular brines from the Salado Formation at or near the stratigraphic horizon of the repository. Simplified GWB contains amounts of Mg, Na, and Cl similar to those in GWB without other minor constituents. The hydration products include brucite (Mg(OH)2) and phase 5 (Mg3(OH)5Cl4H2O). In addition to phase 5, MgO hydration in GWB or simplified GWB produces brucite, whereas MgO hydrated in ERDA-6 only produces brucite. The MgO particle size has had a significant effect on the formation of hydration products: small MgO particles have hydrated before the large particles. MgO has hydrated faster in simplified GWB than in the other two brines. In ERDA-6, the solid-to-liquid ratio has affected the brine pH due to the presence of CaO (~1 wt %) as an impurity in MM MgO. GWB has sufficient dissolved Mg to buffer pH despite small amounts of CaO. Both our results and thermodynamic modeling indicate that phase-5 is the stable Mg-OH-Cl phase in Mg-Na-Cl-dominated brines with ionic strengths and chemical compositions similar to that of GWB. In contrast, phase-3 (Mg2(OH)3Cl4H2O) is the stable phase in the MgCl2

  11. Experimental studies of magnetic perovskites

    Golovanov, Vladimir Valentinovich


    The present work addresses the phenomenon of Giant Magnetoresistance (GMR) and the role of Jahn-Teller distortion in the conduction mechanism of GMR materials. For this purpose, GMR and related perovskites are studied experimentally using infrared reflection spectroscopy, synchrotron x-ray diffraction, and electrical transport measurements. Reflectivity and x-ray diffraction studies of a vacancy doped rhombohedrally distorted GMR material, La0.936Mn0.982O3, indicate the presence of dynamic Jahn-Teller distortion above the magnetic ordering temperature (Tc = 225K) and a substantial reduction of the distortion below Tc. In particular, above Tc, the optical conductivity of large single crystals of the material shows the broad peak around 10,000 cm-1, which shifts towards zero frequency as the ferromagnetic state develops. The peak is attributed to the Jahn-Teller splitting of the two-fold degenerate eg level. Powder x-ray diffraction measurements performed on the same material reveal a sharp 3% reduction of the rhombohedral distortion at the magnetic ordering temperature. This reduction reflects the decrease in the magnitude of the dynamic Jahn-Teller distortion at the magnetic ordering. The transport and magnetic measurements on non Jahn-Teller active La1-xSrxCoO3 perovskites show much lower magnetoresistance, compatible with the conventional double-exchange theory. The relatively high values of magnetoresistance for low doped (x ≤ 0.15) compounds at low temperatures are also interpreted in terms of the double-exchange model.


    Nadir eYehya


    Full Text Available Despite distinct epidemiology and outcomes, pediatric acute respiratory distress syndrome (PARDS is often managed based on evidence extrapolated from treatment of adults. The impact of non-pulmonary processes on mortality, as well as the lower mortality rate compared to adults with ARDS, renders the utilization of short-term mortality as a primary outcome measure for interventional studies problematic. However, data regarding alternatives to mortality are profoundly understudied, and proposed alternatives such as ventilator-free days may be themselves subject to hidden biases. Given the neuropsychiatric and functional impairment in adult survivors of ARDS, characterization of these morbidities in children with PARDS is of paramount importance. The purpose of this review is to frame these challenges in the context of the existing pediatric literature, and using adult ARDS as a guide, suggest potential clinically relevant outcomes deserving of further investigation. The goal is to identify important areas of study in order to better define clinical practice and facilitate future interventional trials in PARDS.

  13. Measuring reinforcement learning and motivation constructs in experimental animals: relevance to the negative symptoms of schizophrenia

    Markou, Athina; Salamone, John D.; Bussey, Timothy; Mar, Adam; Brunner, Daniela; Gilmour, Gary; Balsam, Peter


    The present review article summarizes and expands upon the discussions that were initiated during a meeting of the Cognitive Neuroscience Treatment Research to Improve Cognition in Schizophrenia (CNTRICS; A major goal of the CNTRICS meeting was to identify experimental procedures and measures that can be used in laboratory animals to assess psychological constructs that are related to the psychopathology of schizophrenia. The issues discussed in this review reflec...

  14. Time-Domain Simulations of Transient Species in Experimentally Relevant Environments

    Ueltschi, Tyler W.; Fischer, Sean A.; Apra, Edoardo; Tarnovsky, Alexander N.; Govind, Niranjan; El-Khoury, Patrick Z.; Hess, Wayne P.


    Simulating the spectroscopic properties of short-lived thermal and photochemical reaction intermediates and products is a challenging task, as these species often feature atypical molecular and electronic structures. The complex environments in which such species typically reside in practice add further complexity to the problem. Herein, we tackle this problem in silico using ab initio molecular dynamics (AIMD) simulations, employing iso-CHBr3, namely H(Br)C-Br-Br, as a prototypical system. This species was chosen because it features both a non-conventional C-Br-Br bonding pattern, as well as a strong dependence of its spectral features on the local environment in which it resides, as illustrated in recent experimental reports. The spectroscopic properties of iso-CHBr3 were measured by several groups that captured this transient intermediate in the photochemistry of CHBr3 in the gas phase, in rare gas matrices at 5K, and in solution under ambient laboratory conditions. We simulate the UV-Vis and IR spectra of iso-CHBr3 in all three media, including a Ne cluster (64 atoms) and a methylcyclohexane cage (14 solvent molecules) representative of the matrix isolated and solvated species. We exclusively perform fully quantum mechanical static and dynamic simulations. By comparing our condensed phase simulations to their experimental analogues, we stress the importance of (i) conformational sampling, even at cryogenic temperatures, and (ii) using a fully quantum mechanical description of both solute and bath to properly account for the experimental observables.

  15. Surface Propensity of Atmospherically Relevant Amino Acids Studied by XPS.

    Mocellin, Alexandra; Gomes, Anderson Herbert de Abreu; Araújo, Oscar Cardoso; de Brito, Arnaldo Naves; Bjorneholm, Olle


    Amino acids constitute an important fraction of the water-soluble organic nitrogen (WSON) compounds in aerosols and are involved in many processes in the atmosphere. In this work, we applied XPS to study aqueous solutions of four amino acids: glycine, alanine, valine and methionine, in their zwitterionic forms. We found that amino acids with hydrophilic side chains and smaller size, GLY and ALA, tend to stay in the bulk of the liquid, while the hydrophobic and bigger amino acids, VAL and MET, are found to concentrate more on the surface. We found experimental evidences that the amino acids have preferential orientation relative to the surface, with the hydrophobic side chain being closer to the surface than the hydrophilic carboxylate group. The observed amino acid surface propensity has implications in atmospheric science as the surface interaction play a central role in cloud droplet formation, and they should be considered in climate models.

  16. Relevance of the glutathione system in temporal lobe epilepsy: evidence in human and experimental models.

    Cárdenas-Rodríguez, Noemí; Coballase-Urrutia, Elvia; Pérez-Cruz, Claudia; Montesinos-Correa, Hortencia; Rivera-Espinosa, Liliana; Sampieri, Aristides; Carmona-Aparicio, Liliana


    Oxidative stress, which is a state of imbalance in the production of reactive oxygen species and nitrogen, is induced by a wide variety of factors. This biochemical state is associated with diseases that are systemic as well as diseases that affect the central nervous system. Epilepsy is a chronic neurological disorder, and temporal lobe epilepsy represents an estimated 40% of all epilepsy cases. Currently, evidence from human and experimental models supports the involvement of oxidative stress during seizures and in the epileptogenesis process. Hence, the aim of this review was to provide information that facilitates the processing of this evidence and investigate the therapeutic impact of the biochemical status for this specific pathology.

  17. Experimental evidence for the functional relevance of anion-π interactions

    Dawson, Ryan E.; Hennig, Andreas; Weimann, Dominik P.; Emery, Daniel; Ravikumar, Velayutham; Montenegro, Javier; Takeuchi, Toshihide; Gabutti, Sandro; Mayor, Marcel; Mareda, Jiri; Schalley, Christoph A.; Matile, Stefan


    Attractive in theory and confirmed to exist, anion-π interactions have never really been seen at work. To catch them in action, we prepared a collection of monomeric, cyclic and rod-shaped naphthalenediimide transporters. Their ability to exert anion-π interactions was demonstrated by electrospray tandem mass spectrometry in combination with theoretical calculations. To relate this structural evidence to transport activity in bilayer membranes, affinity and selectivity sequences were recorded. π-acidification and active-site decrowding increased binding, transport and chloride > bromide > iodide selectivity, and supramolecular organization inverted acetate > nitrate to nitrate > acetate selectivity. We conclude that anion-π interactions on monomeric surfaces are ideal for chloride recognition, whereas their supramolecular enhancement by π,π-interactions appears perfect to target nitrate. Chloride transporters are relevant to treat channelopathies, and nitrate sensors to monitor cellular signaling and cardiovascular diseases. A big impact on organocatalysis can be expected from the stabilization of anionic transition states on chiral π-acidic surfaces.

  18. Spectroscopic Studies of Molecular Systems relevant in Astrobiology

    Fornaro, Teresa


    In the Astrobiology context, the study of the physico-chemical interactions involving "building blocks of life" in plausible prebiotic and space-like conditions is fundamental to shed light on the processes that led to emergence of life on Earth as well as to molecular chemical evolution in space. In this PhD Thesis, such issues have been addressed both experimentally and computationally by employing vibrational spectroscopy, which has shown to be an effective tool to investigate the variety of intermolecular interactions that play a key role in self-assembling mechanisms of nucleic acid components and their binding to mineral surfaces. In particular, in order to dissect the contributions of the different interactions to the overall spectroscopic signals and shed light on the intricate experimental data, feasible computational protocols have been developed for the characterization of the spectroscopic properties of such complex systems. This study has been carried out through a multi-step strategy, starting the investigation from the spectroscopic properties of the isolated nucleobases, then studying the perturbation induced by the interaction with another molecule (molecular dimers), towards condensed phases like the molecular solid, up to the case of nucleic acid components adsorbed on minerals. A proper modeling of these weakly bound molecular systems has required, firstly, a validation of dispersion-corrected Density Functional Theory methods for simulating anharmonic vibrational properties. The isolated nucleobases and some of their dimers have been used as benchmark set for identifying a general, reliable and effective computational procedure based on fully anharmonic quantum mechanical computations of the vibrational wavenumbers and infrared intensities within the generalized second order vibrational perturbation theory (GVPT2) approach, combined with the cost-effective dispersion-corrected density functional B3LYP-D3, in conjunction with basis sets of

  19. Relevance of the Glutathione System in Temporal Lobe Epilepsy: Evidence in Human and Experimental Models

    Noemí Cárdenas-Rodríguez


    Full Text Available Oxidative stress, which is a state of imbalance in the production of reactive oxygen species and nitrogen, is induced by a wide variety of factors. This biochemical state is associated with diseases that are systemic as well as diseases that affect the central nervous system. Epilepsy is a chronic neurological disorder, and temporal lobe epilepsy represents an estimated 40% of all epilepsy cases. Currently, evidence from human and experimental models supports the involvement of oxidative stress during seizures and in the epileptogenesis process. Hence, the aim of this review was to provide information that facilitates the processing of this evidence and investigate the therapeutic impact of the biochemical status for this specific pathology.

  20. Relevance of the Glutathione System in Temporal Lobe Epilepsy: Evidence in Human and Experimental Models

    Cárdenas-Rodríguez, Noemí; Coballase-Urrutia, Elvia; Pérez-Cruz, Claudia; Montesinos-Correa, Hortencia; Rivera-Espinosa, Liliana; Sampieri, Aristides; Carmona-Aparicio, Liliana


    Oxidative stress, which is a state of imbalance in the production of reactive oxygen species and nitrogen, is induced by a wide variety of factors. This biochemical state is associated with diseases that are systemic as well as diseases that affect the central nervous system. Epilepsy is a chronic neurological disorder, and temporal lobe epilepsy represents an estimated 40% of all epilepsy cases. Currently, evidence from human and experimental models supports the involvement of oxidative stress during seizures and in the epileptogenesis process. Hence, the aim of this review was to provide information that facilitates the processing of this evidence and investigate the therapeutic impact of the biochemical status for this specific pathology. PMID:25538816

  1. A step-by-step guide to systematically identify all relevant animal studies.

    Leenaars, Marlies; Hooijmans, Carlijn R; van Veggel, Nieky; ter Riet, Gerben; Leeflang, Mariska; Hooft, Lotty; van der Wilt, Gert Jan; Tillema, Alice; Ritskes-Hoitinga, Merel


    Before starting a new animal experiment, thorough analysis of previously performed experiments is essential from a scientific as well as from an ethical point of view. The method that is most suitable to carry out such a thorough analysis of the literature is a systematic review (SR). An essential first step in an SR is to search and find all potentially relevant studies. It is important to include all available evidence in an SR to minimize bias and reduce hampered interpretation of experimental outcomes. Despite the recent development of search filters to find animal studies in PubMed and EMBASE, searching for all available animal studies remains a challenge. Available guidelines from the clinical field cannot be copied directly to the situation within animal research, and although there are plenty of books and courses on searching the literature, there is no compact guide available to search and find relevant animal studies. Therefore, in order to facilitate a structured, thorough and transparent search for animal studies (in both preclinical and fundamental science), an easy-to-use, step-by-step guide was prepared and optimized using feedback from scientists in the field of animal experimentation. The step-by-step guide will assist scientists in performing a comprehensive literature search and, consequently, improve the scientific quality of the resulting review and prevent unnecessary animal use in the future.

  2. Discovering ecologically relevant knowledge from published studies through geosemantic searching

    It is easier to search the globe for research on genes of a local plant or animal than to find local field research on that plant’s ecology. While internet applications can find the closest coffee shop, it is difficult to find where the nearest relevant research was conducted. As a result, ecologi...

  3. Photovoltaic plants: an experimental study

    Cirillo, E.; Fato, I.; Lazzarin, R.

    A photovoltaic unit, designed at the University of Bari and already in operation, is described as well as the methodology followed to measure the main characteristic parameters of its operation. The experimental results, compared with those obtained by applying semi-empirical calculations, suggest that load intermittence should be taken into account by introducing a parameter (N) into the calculation, and that intervention of the solar section control device should be considered.

  4. Experimental approach to shape field relevant blast wave profiles in compressed gas-driven shock tube

    Aravind eSundaramurthy


    Full Text Available Detonation of a high explosive produces shock-blast wave, shrapnel, and gaseous products. While direct exposure to blast is a concern near the epicenter, shock-blast can affect subjects even at farther distances, which is termed as primary blast injury, which is the theme of this work. The shock-blast profile is characterized with blast overpressure, positive time duration, and impulse as shock-blast wave parameters (SWPs. These parameters in turn are a function of field factors, such as the strength of high explosive and the distance of the human subjects from the epicenter. The shape and magnitude of the profile determine the severity of injury to the subjects. As shown in some of our recent works (Chandra et al., 2011;Sundaramurthy et al., 2012;Skotak et al., 2013, the profile not only determines the survival of the animal but also the acute and chronic biomechanical injuries along with the following bio-chemical sequelae. It is extremely important to carefully design and operate the shock tube to produce field relevant SWPs. Furthermore, it is vital to identify and eliminate the artifacts that are inadvertently introduced in the shock-blast profile that may affect the results. In this work, we examine the relationship between shock tube adjustable parameters (SAPs and SWPs that can be used to control the blast profile; the results can be easily applied to many of the laboratory shock tubes. Further, exact replication of shock profile (magnitude and shape can be related to field explosions and can be a standard in comparing results across different laboratories. 40 experiments are carried out by judiciously varying SAPs such as membrane thickness, breech length (66.68 to 1209.68 mm, measurement location, and type of driver gas (nitrogen, helium. The relationships between SAPs and the resulting shock-blast profiles are characterized. Finally, shock-blast profiles of a TNT explosion from ConWep software is compared with the profiles obtained

  5. Cytokines profiling by multiplex analysis in experimental arthritis: which pathophysiological relevance for articular versus systemic mediators?

    Paquet, Joseph; Goebel, Jean-Christophe; Delaunay, Camille; Pinzano, Astrid; Grossin, Laurent; Cournil-Henrionnet, Christel; Gillet, Pierre; Netter, Patrick; Jouzeau, Jean-Yves; Moulin, David


    We have taken advantage of the large screening capacity of a multiplex immunoassay to better define the respective contribution of articular versus systemic cytokines in experimental arthritis. We performed a follow up (from 7 hours to 14 days) multiplex analysis of 24 cytokines in synovial fluid and sera of rats developing Antigen-Induced Arthritis (AIA) and confronted their protein level changes with molecular, biochemical, histological and clinical events occurring in the course of the disease. The time-scheduled findings in arthritic joints correlated with time-dependent changes of cytokine amounts in joint effusions but not with their blood levels. From seven hours after sensitization, high levels of chemokines (MCP-1, MIP1α, GRO/KC, RANTES, eotaxin) were found in synovial fluid of arthritic knees whereas perivascular infiltration occurred in the synovium; local release of inflammatory cytokines (IFNγ, IL-1β, IL-6) preceded the spreading of inflammation and resulted in progressive degradation of cartilage and bone. Finally a local overexpression of several cytokines/adipocytokines poorly described in arthritis (IL-13, IL-18, leptin) was observed. Distinct panels of cytokines were found in arthritic fluid during AIA, and the expected effect of mediators correlated well with changes occurring in joint tissues. Moreover, multiplex analysis could be helpful to identify new pathogenic mediators and to elucidate the mechanisms supporting the efficacy of putative targeted therapies.

  6. Identification of immunologically relevant proteins of Chlamydophila abortus using sera from experimentally infected pregnant ewes.

    Marques, P X; Souda, Puneet; O'Donovan, J; Gutierrez, J; Gutierrez, E J; Worrall, S; McElroy, M; Proctor, A; Brady, C; Sammin, D; Basset, H F; Whitelegge, Julian P; Markey, B E; Nally, J E


    Chlamydophila abortus is an intracellular pathogen and the etiological agent of enzootic abortion of ewes (EAE). C. abortus has a biphasic development cycle; extracellular infectious elementary bodies (EB) attach and penetrate host cells, where they give rise to intracellular, metabolically active reticulate bodies (RB). RB divide by binary fission and subsequently mature to EB, which, on rupture of infected cells, are released to infect new host cells. Pregnant ewes were challenged with 2 x 10(6) inclusion forming units (IFU) of C. abortus cultured in yolk sac (comprising both EB and RB). Serum samples were collected at 0, 7, 14, 21, 27, 30, 35, 40, and 43 days postinfection (dpi) and used to identify antigens of C. abortus expressed during disease. Additionally, sera from fetal lambs were collected at 30, 35, 40, and 43 dpi. All serum samples collected from experimentally infected pregnant ewes reacted specifically with several antigens of EB as determined by one-dimensional (1-D) and 2-D gel electrophoresis; reactive antigens identified by mass spectrometry included the major outer membrane protein (MOMP), polymorphic outer membrane protein (POMP), and macrophage infectivity potentiator (MIP) lipoprotein.

  7. [Some notes on the history of the experimental surgery laboratory. Reflections on its relevance in education and surgical research].

    de la Garza-Rodea, Anabel Sofía; Padilla-Sánchez, Luis; de la Garza-Aguilar, Javier; Neri-Vela, Rolando


    The progress of medicine has largely been due to research, and for surgery, in particular, the experimental surgical laboratory has been considered fundamental to the surgeon's education. In this study, a general view of experimental surgery is given in animal models based on bioethical norms as well as to design, create and apply different surgical procedures before performing in humans. Experimental surgery also facilitates surgical teaching and promotes the surgeon's scientific reasoning. Methods. This is a retrospective and descriptive study. Data were collected from direct and indirect sources of available publications on the historical, bioethical and educational aspects of medicine, focusing on surgery. The important facts corresponding to the field of experimental surgery and applicable in Mexico were selected. Concepts of experimental surgical models and of the experimental surgery laboratory were described. Bioethical considerations are emphasized for care of experimental animals. Finally, this work focuses on the importance of surgical experimentation in current and future development of the surgical researcher. Conclusions. Experimentation with animal models in a surgical laboratory is essential for surgical teaching and promotes development of the scientific thought in the surgeon. It is necessary for surgical research and is fundamental for making progress in surgery, treatment and medicine as science.

  8. Experimental investigations relevant for hydrogen and fission product issues raised by the Fukushima accident

    Gupta, Sanjeev [Becker Technologies GmbH, Eschborn (Germany)


    The accident at Japan's Fukushima Daiichi nuclear power plant in March 2011, caused by an earthquake and a subsequent tsunami, resulted in a failure of the power systems that are needed to cool the reactors at the plant. The accident progression in the absence of heat removal systems caused Units 1-3 to undergo fuel melting. Containment pressurization and hydrogen explosions ultimately resulted in the escape of radioactivity from reactor containments into the atmosphere and ocean. Problems in containment venting operation, leakage from primary containment boundary to the reactor building, improper functioning of standby gas treatment system (SGTS), unmitigated hydrogen accumulation in the reactor building were identified as some of the reasons those added-up in the severity of the accident. The Fukushima accident not only initiated worldwide demand for installation of adequate control and mitigation measures to minimize the potential source term to the environment but also advocated assessment of the existing mitigation systems performance behavior under a wide range of postulated accident scenarios. The uncertainty in estimating the released fraction of the radionuclides due to the Fukushima accident also underlined the need for comprehensive understanding of fission product behavior as a function of the thermal hydraulic conditions and the type of gaseous, aqueous, and solid materials available for interaction, e.g., gas components, decontamination paint, aerosols, and water pools. In the light of the Fukushima accident, additional experimental needs identified for hydrogen and fission product issues need to be investigated in an integrated and optimized way. Additionally, as more and more passive safety systems, such as passive autocatalytic recombiners and filtered containment venting systems are being retrofitted in current reactors and also planned for future reactors, identified hydrogen and fission product issues will need to be coupled with the

  9. CancerResource: a comprehensive database of cancer-relevant proteins and compound interactions supported by experimental knowledge.

    Ahmed, Jessica; Meinel, Thomas; Dunkel, Mathias; Murgueitio, Manuela S; Adams, Robert; Blasse, Corinna; Eckert, Andreas; Preissner, Saskia; Preissner, Robert


    During the development of methods for cancer diagnosis and treatment, a vast amount of information is generated. Novel cancer target proteins have been identified and many compounds that activate or inhibit cancer-relevant target genes have been developed. This knowledge is based on an immense number of experimentally validated compound-target interactions in the literature, and excerpts from literature text mining are spread over numerous data sources. Our own analysis shows that the overlap between important existing repositories such as Comparative Toxicogenomics Database (CTD), Therapeutic Target Database (TTD), Pharmacogenomics Knowledge Base (PharmGKB) and DrugBank as well as between our own literature mining for cancer-annotated entries is surprisingly small. In order to provide an easy overview of interaction data, it is essential to integrate this information into a single, comprehensive data repository. Here, we present CancerResource, a database that integrates cancer-relevant relationships of compounds and targets from (i) our own literature mining and (ii) external resources complemented with (iii) essential experimental and supporting information on genes and cellular effects. In order to facilitate an overview of existing and supporting information, a series of novel information connections have been established. CancerResource addresses the spectrum of research on compound-target interactions in natural sciences as well as in individualized medicine; CancerResource is available at:

  10. Experimental study of MWEDM technology

    DI Shi-chun; HUANG Rui-ning; CHI Guan-xin; ZHAO Wan-sheng


    This work deals with an experimental investigation of the machining characteristics of Micro Wire Electrical Discharge Machining (MWEDM). The MWEDM process consists of only one cutting operation varying with machining conditions. Experimental results show that the peak current and pulse duration have an obvious influence on surface roughness and machining time, and they also have an optimum value for the highest cutting speed. The servo reference voltage influences the surface roughness and machining time as well. In particular,the surface characteristics of work-pieces and a micro wire electrode were analyzed in detail too. Utilizing a micro wire electrode with diameter 30μm, MWEDM can machine a micro slot 38μm wide, which proves that the discharge gap can be controlled not more than 4μm. It can also machine micro gears respectively with a module 40μm, thickness 1mm, and a module 100μm, thickness 3.5mm. All kinds of micro shaped holes and complex micro parts can be easily machined as well.

  11. Studies on Ammonia Spectral Signatures Relevant to Jupiter's Clouds

    Oza, A. U.; Marschall, J.; Wong, M. H.; Kalogerakis, K. S.


    Observational evidence and thermochemical models indicate an abundance of ammonia ice clouds in Jupiter's atmosphere. However, spectrally identifiable ammonia ice clouds are found covering less than 1% of Jupiter's atmosphere, notably in turbulent areas [1,2]. Current literature suggests two possible explanations: coating by a hydrocarbon haze and/or photochemical processing ("tanning")[2,3]. We are pursuing a research program investigating the above hypotheses. In the experiments, thin films of ammonia ices are deposited in a cryogenic apparatus, coated with hydrocarbons, and characterized by infrared spectroscopy. The ice films can be irradiated by ultraviolet light to study their photochemistry. The spectroscopic measurements aim to identify the processes that control the optical properties of the ice mixtures and quantify their dependence on the identity of the coating, the temperature, and the ice composition. We have observed a consistent suppression of the ammonia absorption feature at 3 μm with coverage by thin layers of hydrocarbons. Modeling calculations of the multi-layer thin films assist in the interpretation of the experimental results and reveal the role of optical interference in masking the aforementioned ammonia spectral feature. The implications of these results for Jupiter's atmosphere will be discussed. Funding from the NSF Planetary Astronomy Program under grant AST-0206270 and from the NASA Outer Planets Research Program under grant NNG06GF37G is gratefully acknowledged. The participation of Anand Oza (Princeton University) was made possible by the NSF Research Experiences for Undergraduates Program under grant PHY-0353745. 1. S. K. Atreya, A.-S. Wong, K. H. Baines, M. H. Wong, T. C. Owen, Planet. Space Science 53, 498 (2005). 2. K. H. Baines, R. W. Carlson, and L. W. Kamp, Icarus 159, 74 (2002). 3. A.-S. Wong, Y. L. Yung, and A. J. Friedson, Geophys. Res. Lett. 30, 1447 (2003).

  12. Acquisition and loss of desiccation tolerance in seeds : from experimental model to biological relevance

    Dekkers, Bas J W|info:eu-repo/dai/nl/326091572; Costa, Maria Cecilia D; Maia, Julio; Bentsink, Leónie|info:eu-repo/dai/nl/241338735; Ligterink, Wilco; Hilhorst, Henk W M


    MAIN CONCLUSION: Besides being an important model to study desiccation tolerance, the induction of desiccation tolerance in germinated seeds may also play an ecological role in seedling establishment. Desiccation tolerance (DT) is the ability of certain organisms to survive extreme water losses with

  13. Fisetin, a dietary flavonoid, ameliorates experimental colitis in mice: Relevance of NF-κB signaling.

    Sahu, Bidya Dhar; Kumar, Jerald Mahesh; Sistla, Ramakrishna


    Fisetin, a dietary flavonoid, is commonly found in many fruits and vegetables. Although studies indicate that fisetin has an anti-inflammatory property, little is known about its effects on intestinal inflammation. The present study investigated the effects of the fisetin on dextran sulphate sodium (DSS)-induced murine colitis, an animal model that resembles human inflammatory bowel disease. Fisetin treatment to DSS-exposed mice significantly reduced the severity of colitis and alleviated the macroscopic and microscopic signs of the disease. Moreover, fisetin reduced the levels of myeloperoxidase activity, the production of proinflammatory cytokines, tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β) and interleukin-6 (IL-6) and the expressions of COX-2 and iNOS in the colon tissues. Further studies revealed that fisetin suppressed the activation of NF-κB (p65) by inhibiting IκBα phosphorylation and NF-κB (p65)-DNA binding activity and attenuated the phosphorylation of Akt and the p38, but not ERK and JNK MAPKs in the colon tissues of DSS-exposed mice. In addition, DSS-induced decline in reduced glutathione (GSH) and the increase in malondialdehyde (MDA) levels were significantly restored by oral fisetin. Furthermore, the results from in vitro studies showed that fisetin significantly reduced the pro-inflammatory cytokine and mediator release and suppressed the degradation and phosphorylation of IκBα with subsequent nuclear translocation of NF-κB (p65) in lipopolysaccharide (LPS)-stimulated mouse primary peritoneal macrophages. These results suggest that fisetin exerts anti-inflammatory activity via inhibition of Akt, p38 MAPK and NF-κB signaling in the colon tissues of DSS-exposed mice. Thus, fisetin may be a promising candidate as pharmaceuticals or nutraceuticals in the treatment of inflammatory bowel disease. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Acquisition and loss of desiccation tolerance in seeds: from experimental model to biological relevance.

    Dekkers, Bas J W; Costa, Maria Cecilia D; Maia, Julio; Bentsink, Leónie; Ligterink, Wilco; Hilhorst, Henk W M


    Besides being an important model to study desiccation tolerance, the induction of desiccation tolerance in germinated seeds may also play an ecological role in seedling establishment. Desiccation tolerance (DT) is the ability of certain organisms to survive extreme water losses without accumulation of lethal damage. This was a key feature in the conquering of dry land and is currently found in all taxa including bacteria, fungi, roundworms and plants. Not surprisingly, studies in various fields have been performed to unravel this intriguing phenomenon. In flowering plants, DT is rare in whole plants (vegetative tissues), yet is common in seeds. In this review, we present our current understanding of the evolution of DT in plants. We focus on the acquisition of DT in seeds and the subsequent loss during and after germination by highlighting and comparing research in two model plants Medicago truncatula and Arabidopsis thaliana. Finally, we discuss the ability of seeds to re-establish DT during post-germination, the possible ecological meaning of this phenomenon, and the hypothesis that DT, in combination with dormancy, optimizes seedling establishment.

  15. Temporal dynamics of relief in avoidance conditioning and fear extinction: Experimental validation and clinical relevance.

    Vervliet, Bram; Lange, Iris; Milad, Mohammed R


    The learning principles that guide the acquisition and extinction of avoidance are not fully understood. We developed a novel paradigm to study the temporal dynamics of relief, a putative reinforcer of avoidance, and the recovery of fear and avoidance following extinction. During conditioning, the avoidance action canceled the aversive unconditional stimulus (US), without terminating the predictive conditional stimulus (CS). Relief pleasantness was rated after fixed CS offsets, when US omission occured. Avoidance was effective to one CS, but not to another, to track stimulus-specific avoidance learning. Fear was extinguished under response prevention in a separate context. Recovery tests took place 24 h later, in both contexts and with a monetary cost added to the avoidance action. We found that avoidance gradually became stimulus-specific during conditioning, but hardly recovered during delayed testing. Across all phases, initial omissions of the aversive US triggered relief that gradually declined over consecutive omissions, in line with a theoretical prediction error signal. Participants that scored low on distress tolerance, however, displayed sustained levels of relief over continuous omissions. We propose that such forms of sustained relief may produce over-reinforcement of foregoing avoidance actions and promote the development of pathological avoidance. The current paradigm represents an efficacious tool to study the temporal dynamics of relief across avoidance learning and fear extinction and to characterize relief dysregulations in relation to psychopathology. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  16. Kinematics of experimental forced folds and their relevance to cross-section balancing

    Couples, Gary D.; Stearns, David W.; Handin, John W.


    We report the results of a series of laboratory experiments in which packages of layers (consisting of rock and lead) are deformed under 50 MPa confining pressure into forced folds by the uplift and rotation of pre-machined steel forcing blocks. The models are not fully scaled, but the geometries resulting form the deformation are remarkably similar to many natural forced folds observed in the U.S. Rocky Mountains foreland. During the folding, detachment and quantifiable layer-parallel translation occur between the layered sequence and the forcing assembly, confirming limited observations from earlier model studies. Away from the fold, there is a pattern of movement in which the layered sequence first moves away from the uplift, but, with greater structural relief, those motions reverse their sense to become layer-parallel translations towards the uplift. The very ductile lead unit at the base of the layered sequence flows laterally, especially across the crest of the uplift to the downthrown block, in response to pressure gradients which are inherent to asymmetric uplifts. The flow of this ductile unit causes layer-parallel translation of the rock layers, thereby transporting material into the fold. If the models were to be treated as proposed cross sections, and if they were subjected to the usual techniques of cross-section balancing, incorrect interpretations would result; this is because there are no suitable sites for either pin lines or no-flow boundaries.

  17. Experimental studies of occupation times in turbulent flows

    Mann, J.; Ott, Søren; Pécseli, H.L.;


    The motion of passively convected particles in turbulent flows is studied experimentally in approximately homogeneous and isotropic turbulent flows, generated in water by two moving grids. The simultaneous trajectories of many small passively convected, neutrally buoyant, polystyrene particles ar....... In the present formulation, the results of the analysis are relevant for understanding details in the feeding rate of micro-organisms in turbulent waters, for instance....

  18. In support of descriptive studies; relevance to translational research

    Marincola Francesco M


    Full Text Available Abstract The contemporary scientific establishment equates hypothesis testing to good science. This stance bypasses the preliminary need to identify a worthwhile hypothesis through rigorous observation of natural processes. If alleviation of human suffering is claimed as the goal of a scientific undertaking, it would be unfair to test a hypothesis whose relevance to human disease has not been satisfactorily proven. Here, we argue that descriptive investigations based on direct human observation should be highly valued and regarded essential for the selection of worthwhile hypotheses while the pursuit of costly scientific investigations without such evidence is a desecration of the cause upon which biomedical research is grounded. There are good things so in the tide pools and interesting thoughts to be generated from the seeing. Every new eye applied to the peephole which looks out at the world may fish in some new beauty and some new pattern, and the world of the human mind must be enriched by such fishing. John Steinbeck – Foreword to the Third Edition of Ed Ricketts' "Tides".

  19. Experimental studies of neutrino oscillations

    Kajita, Takaaki


    The 2015 Nobel Prize in physics has been awarded to Takaaki Kajita and Arthur McDonald "for the discovery of neutrino oscillations, which shows that neutrinos have mass". Takaaki Kajita of Tokyo University is a Japanese physicist, known for neutrino experiments at the Kamiokande and its successor, Super-Kamiokande. This volume of collected works of Kajita on neutrino oscillations provides a good glimpse into as well as a record of the rise and the role of Asian research in the frontiers of neutrino physics. Japan is now a major force in the study of the 3 families of neutrinos. Much remains to be done to clarify the Dirac vs. Majorana nature of the neutrino, and the cosmological implications of the neutrino. The collected works of Kajita and his Super-Kamiokande group will leave an indelible foot-print in the history of big and better science.


    Cuzdriorean Dan Dacian


    Full Text Available This empirical study extends the study conducted by Vladu, Grosanu and Cuzdriorean (2012 and reached similar conclusions. This particular research was conducted with the scope of assessing the impact of: positive bias, persuasive language, creative visual manipulation and performance comparisons over the unsophisticated users of accounting opinion. We have chosen this particular category since retail investors have been identified as relying on the information provided in corporate annual reports for decision making (Wills, 2008. Based on their relative inexperience and limited knowledge of these investors it is plausible that they can be mislead easily comparing to more sophisticated users of accounting information, as financial analysts. The main argument for conducting such a research is the fact that little research was conducted so far and the effects of creative disclosure on investment decision cannot be assessed so far. Based on this, we conducted a laboratory experiment where participants where provided with an informational set of financial data and required to make an investment decision. Our results document that the users perceptions is strongly affected by creative disclosure, contradictory with previous results documented in the literature, that their opinion cannot be influenced since they relay mostly on numerical information and less on the narrative segments of the financial statements. Even if our sample compressed few participants, we consider the results conclusive. A further research can extend the sample and test if our research hypothesis can be validated. Another possible spring of research can deal with the assessing of the opinion of the users of accounting information that are not considered unsophisticated, as financial analysts.

  1. Practical Interests, Relevant Alternatives, and Knowledge Attributions: an Empirical Study.

    May, Joshua; Sinnott-Armstrong, Walter; Hull, Jay G; Zimmerman, Aaron


    In defending his interest-relative account of knowledge, Jason Stanley relies heavily on intuitions about several bank cases. We experimentally test the empirical claims that Stanley seems to make concerning our common-sense intuitions about these cases. Additionally, we test the empirical claims that Jonathan Schaffer seems to make, regarding the salience of an alternative, in his critique of Stanley. Our data indicate that neither raising the possibility of error nor raising stakes moves most people from attributing knowledge to denying it. However, the raising of stakes (but not alternatives) does affect the level of confidence people have in their attributions of knowledge. We argue that our data impugn what both Stanley and Schaffer claim our common-sense judgments about such cases are.

  2. Ovine and Caprine Toxoplasmosis: Experimental Study

    Shawkat Q. Lafi


    Full Text Available Eighteen mature ewes of the Mytilene breed and 18 mature Local- Damascus crossbred goats, seronegative for Toxoplasma gondii (T. gondii by ELISA were used. All animals were mated after synchronization of estrus. On day 90 of pregnancy, animals were randomly assigned to 3 experimental groups; 6 ewes (S1 and 6 goats (G1 were orally inoculated by stomach tube with 1000 oocysts; 6 ewes (S2 and 6 goats (G2 were orally inoculated with a non-infected control inoculum. On day 140+2 of pregnancy, the remaining 6 ewes (S3 and 6 goats (G3 were inoculated by stomach tube with 3000 oocysts. Positive T. godii DNA was detected in 94% of fetal and maternal blood, 95% fetal tissue, 89% pre-colostral udder secretions and 12.5% milk samples using Polymerase Chain Reaction (PCR. Infected animals and their live newborns was seropositive (ELISA until the end of the study. PCR was able to detect T. gondii DNA in maternal blood of infected animals 3-5 days before abortion occurred. This time period may be used to implement preventive and therapeutic measure to reduce abortion rate and associated economic losses. Since milk and milk products are important food sources in rural areas and in many cases it is used unpasteurized before consumption. The T. gondii DNA, detected by PCR in milk samples of infected animals, increases the possibility that the parasite is transmitted through consumption of unpasteurized milk which is a highly relevant result for public health considerations and providing valuable information for future research.

  3. Experimental Economics method to study pupils motivation

    Lionel Page


    Experimental Economics provide a new set of tools in the tool box of the education economist. This paper review why experimental method may be useful to study how pupils behaviour, formed from their preference and beliefs, may influence their success or failure at school, what are its advantages and what are its limits. Behavioural Economics - Education - Public Policy

  4. Assessing the relevance of ecotoxicological studies for regulatory decision making

    Rudén, Christina; Adams, Julie; Ågerstrand, Marlene; Brock, Theo C.M.; Poulsen, Veronique; Schlekat, Christian E.; Wheeler, James R.; Henry, Tala R.


    Regulatory policies in many parts of the world recognize either the utility of or the mandate that all available studies be considered in environmental or ecological hazard and risk assessment (ERA) of chemicals, including studies from the peer-reviewed literature. Consequently, a vast array of d

  5. Study on the relevance of some of the description methods for plateau-honed surfaces

    Yousfi, M.; Mezghani, S.; Demirci, I.; El Mansori, M.


    Much work has been undertaken in recent years into the determination of a complete parametric description of plateau-honed surfaces with the intention of making a link between the process conditions, the surface topography and the required functional performances. Different advanced techniques (plateau/valleys decomposition using the normalized Abbott-Firestone curve or morphological operators, multiscale decomposition using continuous wavelets transform, etc) were proposed and applied in different studies. This paper re-examines the current state of developments and addresses a discussion on the relevance of the different proposed parameters and characterization methods for plateau-honed surfaces by considering the control loop manufacturing-characterization-function. The relevance of appropriate characterization is demonstrated through two experimental studies. They consider the effect of the most plateau honing process variables (the abrasive grit size and abrasive indentation velocity in finish-honing and the plateau-honing stage duration and pressure) on cylinder liner surface textures and hydrodynamic friction of the ring-pack system.

  6. The Importance of Physiologically Relevant Cell Lines for Studying Virus–Host Interactions

    David Hare


    Full Text Available Viruses interact intimately with the host cell at nearly every stage of replication, and the cell model that is chosen to study virus infection is critically important. Although primary cells reflect the phenotype of healthy cells in vivo better than cell lines, their limited lifespan makes experimental manipulation challenging. However, many tumor-derived and artificially immortalized cell lines have defects in induction of interferon-stimulated genes and other antiviral defenses. These defects can affect virus replication, especially when cells are infected at lower, more physiologically relevant, multiplicities of infection. Understanding the selective pressures and mechanisms underlying the loss of innate signaling pathways is helpful to choose immortalized cell lines without impaired antiviral defense. We describe the trials and tribulations we encountered while searching for an immortalized cell line with intact innate signaling, and how directed immortalization of primary cells avoids many of the pitfalls of spontaneous immortalization.

  7. Methodologies and study designs relevant to medical education research.

    Turner, Teri L; Balmer, Dorene F; Coverdale, John H


    Research is an important part of educational scholarship. Knowledge of research methodologies is essential for both conducting research as well as determining the soundness of the findings from published studies. Our goals for this paper therefore are to inform medical education researchers of the range and key components of educational research designs. We will discuss both qualitative and quantitative approaches to educational research. Qualitative methods will be presented according to traditions that have a distinguished history in particular disciplines. Quantitative methods will be presented according to an evidence-based hierarchy akin to that of evidence-based medicine with the stronger designs (systematic reviews and well conducted educational randomized controlled trials) at the top, and weaker designs (descriptive studies without comparison groups, or single case studies) at the bottom. It should be appreciated, however, that the research question determines the study design. Therefore, the onus is on the researcher to choose a design that is appropriate to answering the question. We conclude with an overview of how educational researchers should describe the study design and methods in order to provide transparency and clarity.

  8. Estimation and relevance of depth correction in paediatric renal studies

    Lythgoe, M.F.; Gradwell, M.J.; Evans, K.; Gordon, I. [Department of Radiology, Great Ormond Street Hospital for Children NHS Trust, London (United Kingdom)


    Measurement of absolute renal function by gamma camera techniques requires knowledge of kidney depth to correct for soft tissue attenuation, there is debate about the need to take depth into account when only relative renal function is estimated. The aim of this study was to derive a formula for renal depth in children and to assess the importance of depth correction when relative renal function is assessed with dimercaptosuccinic acid (DMSA) on the gamma camera. In this study, kidney depths were derived from measurements on abdominal computerised tomography (CT) images in 57 children in the supine position with two normally located kidneys. Using best-subset regression analysis, one formula for both left and right kidney depth (KD, cm) was developed based on the easily measured parameters of height (H, cm) and body weight (W, kg). The inclusion of extra variables was found to significantly improve the model compared with a model using weight alone (P<0.005). A second group of 19 children who underwent technetium-99m DMSA scans, had differential function estimated from both anterior and posterior views and the geometric mean method. The mean difference in differential renal function calculated by the geometric mean method versus the posterior image was only 1.2%. In conclusion, we present a new formula for the estimation of paediatric kidney depth for the absolute quantitation of kidney uptake. Further, for normally located kidneys it appears unnecessary to use the geometric mean method or to correct for individual renal depth when calculating differential function. (orig.) With 2 figs., 1 tab., 22 refs.

  9. Towards studies of organizational behaviour with greater local relevance

    Peter B. Smith


    Full Text Available Theories of organizational behaviour mostly originated in North America. In testing their applicability elsewhere, attention must be given to differences in local environments and inthe values of local employees. Within Latin America, the prevalence of high collectivism and power distance are particularly important. Employees’ attachment to their organization has been shown to differ within collectivistic cultures. The argument is illustrated by two Latin American studies. Firstly, the ways in which managers handle work events within Mexico, Colombia, Brazil, Chile and Argentina are compared. Secondly, cross-national work problems of employees from these countries are surveyed. The results emphasize the need to take account of variability within the region, and the need to use measures that capture locally important issues. -- Las teorías del comportamiento organizacional se han originado principalmente en Américadel Norte. Al probar su aplicabilidad en otras regiones culturales, debe prestarse atención a las diferencias en los ambientes y en los valores de los empleados locales. Dentro de Latinoamérica, la prevalencia de altos niveles de colectivismo y distancia al poder es particularmenteimportante. En ese sentido, se ha demostrado que el apego de los empleados hacia su organización difiere dentro de las culturas colectivistas. El argumento se ilustra por dosestudios latinoamericanos. En el primero, se compara la forma en que los gerentes manejan los eventos laborales dentro de México, Colombia, Brasil, Chile y Argentina. En el segundo,se examinan los problemas laborales transnacionales de los empleados de estos países. Los resultados enfatizan la necesidad de utilizar medidas que capturen aspectos localmente importantes.

  10. Differences of relevance in implicit and explicit memory tests:An ERP study

    LI YueTing; LI Qi; GUO ChunYan


    An ERP study was conducted to explore the differences between other-relevant words and possessor-relevant words in implicit and explicit memory tests.The results show that other-relevant words are associated with a more negative ERP than possessor-relevant words during 300-900 ms whether in the implicit or the explicit memory tests.The N400 effect is also found in semantic processing of social materials.There is an ERP dissociation of retrieval formats between the implicit and the explicit memory tests during 700-900 ms,namely,there is no difference between other-relevant words and possessor-relevant words in the implicit memory while there is a significant difference between them in the explicit memory.Observed through Curry 6.0,the analysis of neural sources for other-relevant words and possessor-relevant words indicates that they have different locations.At 400 ms,activity is found in the left precuneus during possessor-relevant words processing.Both the right and the left precuneus are activated during other-relevant words processing.However,at 600 ms their location is both in the left precuneus.In a word,our results show that there exists a cognitive difference between other-relevant words and possessor-relevant words,and other-relevant words closely related to the percipient himself/herself are strongly responded to,which reflects that there is a bigger attention bias to the stimuli concerning the percipient himself/herself than to processor-relevant words.

  11. Experimental design of a waste glass study

    Piepel, G.F.; Redgate, P.E.; Hrma, P.


    A Composition Variation Study (CVS) is being performed to support a future high-level waste glass plant at Hanford. A total of 147 glasses, covering a broad region of compositions melting at approximately 1150{degrees}C, were tested in five statistically designed experimental phases. This paper focuses on the goals, strategies, and techniques used in designing the five phases. The overall strategy was to investigate glass compositions on the boundary and interior of an experimental region defined by single- component, multiple-component, and property constraints. Statistical optimal experimental design techniques were used to cover various subregions of the experimental region in each phase. Empirical mixture models for glass properties (as functions of glass composition) from previous phases wee used in designing subsequent CVS phases.

  12. On Feature Relevance in Image-Based Prediction Models: An Empirical Study

    Konukoglu, E.; Ganz, Melanie; Van Leemput, Koen


    the community. In this article, we present an empirical study on the relevant features produced by two recently developed discriminative learning algorithms: neighborhood approximation forests (NAF) and the relevance voxel machine (RVoxM). Specifically, we examine whether the sets of features these methods...

  13. Teaching Social Studies for Newcomer English Language Learners: Toward Culturally Relevant Pedagogy

    Choi, Yoonjung


    Through this case study the author explores how an exemplary teacher utilized social studies curriculum and pedagogy to engage English language learners (ELLs) in learning in a culturally relevant and meaningful way and discusses practical implications for teaching and learning.

  14. Teaching Social Studies for Newcomer English Language Learners: Toward Culturally Relevant Pedagogy

    Choi, Yoonjung


    Through this case study the author explores how an exemplary teacher utilized social studies curriculum and pedagogy to engage English language learners (ELLs) in learning in a culturally relevant and meaningful way and discusses practical implications for teaching and learning.

  15. Laboratory Study of Magnetic Reconnection in 3D Geometry Relevant to Magnetopause and Magnetotail

    Ren, Y.; Lu, Q.; Ji, H.; Mao, A.; Wang, X.; E, P.; Wang, Z.; Xiao, Q.; Ding, W.; Zheng, J.


    Laboratory Study of Magnetic Reconnection in 3D Geometry Relevant to Magnetopause and Magnetotail Y. Ren1,2, Quaming Lu3, Hantao Ji1,2, Aohua Mao1, Xiaogang Wang1, Peng E1, Zhibin Wang1, Qingmei Xiao1, Weixing Ding4, Jinxing Zheng51 Harbin Institute of Technology, Harbin, China2 Princeton Plasma Physics Laboratory, Princeton University, Princeton, NJ 08543 3University of Science and Technology of China, Hefei, China 4University of California at Los Angeles, Los Angeles, CA, 90095 5ASIPP, Hefei, China A new magnetic reconnection experiment, Harbin reconnection eXperiment (HRX), is currently being designed as a key part of Space Plasma Environment Research Facility (SPERF) at Harbin Institute of Technology in Harbin, China. HRX aims to provide a unique experimental platform for studying reconnections in 3D geometry relevant to magnetopause and magnetotail to address: the role of electron and ion-scale dynamics in the current sheet; particle and energy transfer from magnetosheath to magnetosphere; particle energization/heating mechanisms during magnetic reconnection; 3D effects in fast reconnection, e.g. the role of 3D magnetic null point. HRX employs a unique set of coils to generate the required 3D magnetic geometry and provides a wide range of plasma parameters. Here, important motivating scientific problems are reviewed and the physics design of HRX is presented, including plasma parameters determined from Vlasov scaling law, reconnection scenarios explored using vacuum magnetic field calculations and numerical simulations of HRX using hybrid and MHD codes. Plasma diagnostics plan and engineering design of important coils will also be briefly presented.

  16. Plutonium chemistry under conditions relevant for WIPP performance assessment. Review of experimental results and recommendations for future work

    Oversby, Virginia M.


    The Waste Isolation Pilot Plant (WIPP), located at a depth of 650 m in bedded salt at a site approximately 40 km east of Carlsbad, New Mexico, was constructed by the US Department of Energy for the disposal of transuranic wastes arising from defense-related activities. The disposal site is regulated by the US Environmental Protection Agency (EPA). During the process leading to certification of the site for initial emplacement of waste, EEG and their contractors reviewed the DOE Compliance Certification Application (CCA) and raised a number of issues. This report reviews the issues related to the chemistry of plutonium as it will affect the potential for release of radioactivity under WIPP conditions. Emphasis is placed on conditions appropriate for the Human Intrusion scenario(s), since human intrusion has the largest potential for releasing radioactivity to the environment under WIPP conditions. The most significant issues that need to be addressed in relation to plutonium chemistry under WIPP conditions are (1) the effects of heterogeneity in the repository on Pu concentrations in brines introduced under the human intrusion scenario, (2) the redox state of Pu in solution and potential for plutonium in solid phases to have a different redox state from that in the solution phase, (3) the effect of organic ligands on the solubility of Pu in WIPP-relevant brines, and (4) the effects of TRU waste characteristics in determining the solubility of Pu. These issues are reviewed with respect to the treatment they received in the DOE CCA, DOE’s response to EEG’s comments on the CCA, and EPA’s response to those comments as reflected in the final EPA rule that led to the opening of the WIPP. Experimental results obtained in DOE’s Actinide Source-Term Test Program (STTP) during the last two years are reviewed and interpreted in the light of other developments in the field of Pu solution chemistry. This analysis is used as the basis for a conceptual model for Pu

  17. Experimental Approaches to Studying Biological Electron Transfer.

    Scott, Robert A.; And Others


    Provides an overview on biological electron-transfer reactions, summarizing what is known about how distance, spatial organization, medium, and other factors affect electron transfer. Experimental approaches, including studies of bimolecular electron transfer reactions (electrostatic effects and precursor complexes), are considered. (JN)

  18. Experimental Studies on Biosensing by SPR

    Sun, Xiaochun; Shiokawa, Showko; Matsui, Yosikazu


    Biosensing using surface plasmon resonance is experimentally studied. The results obtained by detecting the bioresponse of the α-Feto protein system and cyclic experiments show that this technique has potential application in the field of biosensing. The effects of an organic layer on detecting sensitivity and restoration of sensors are also discussed.




    Experimental study of the BNL Electron Beam Test Stand (EBTS), which is a prototype of the Relativistic Heavy Ion Collider (RHIC) Electron Beam Ion Source (EBIS), is currently underway. The basic physics and engineering aspects of a high current EBIS implemented in EBTS are outlined and construction of its main systems is presented. Efficient transmission of a 10 A electron beam through the ion trap has been achieved. Experimental results on generation of multiply charged ions with both continuous gas and external ion injection confirm stable operation of the ion trap.

  20. Experimental study of negative capacitance in LEDs

    FENG Lie-feng; WANG Jun; ZHU Chuan-yun; CONG Hong-xia; CHEN Yong; WANG Cun-da


    The experimental study on negative capacitance(NC) of various light-emitting diodes(LEDs) is presented.Experimental result shows that all LEDs display the NC phenomenon.The voltage modulated electroluminescence(VMEL) experiment confirms that the reason of negative capacitance is the strong recombination of the injected carriers in the active region of luminescence.The measures also verify that the dependence of NC on voltage and frequency in different LEDs is similar: NC phenomenon is more obvious with higher voltage or lower frequency.

  1. Pore-Scale Research of Trapping Mechanisms and Caprock Sealing Efficiency Relevant to CO2 Sequestration: Experimental Capability Development at EMSL/PNNL

    Wietsma, T. W.; Zhang, C.; Oostrom, M.; Grate, J. W.


    Capture and sequestration of anthropogenic CO2 in depleted oil and gas reservoirs, unminable coal seams and deep saline aquifer are being intensively studied as a promising strategy to mitigate CO2 emission into the atmosphere. Two critical research areas are trapping mechanisms and caprock sealing efficiency, which are controlled by interfacial processes at the fluid-fluid and fluid-rock interfaces. Fundamental understanding of capillary/viscous effects and host rock heterogeneity on trapping mechanisms and sealing efficiency can be gained through micromodel pore-scale displacement experiments. Experimental capabilities are being developed at the Environmental Molecular Sciences Lab (EMSL), Pacific Northwest National Laboratory (PNNL) to study coupled flow and reactive transport processes in complex systems at the pore-scale at relevant storage pressures and temperatures. This presentation highlights our strategies for design and construction of a unique high-pressure system for micromodel experimentation and a capability for visualizing dynamic interfacial processes using a solvatochromic dye under supercritical conditions. Preliminary results on displacement of brine by supercritical CO2 will be presented.

  2. Experimental and Modelling Studies of Biomass Pyrolysis

    Ka Leung Lam; Adetoyese Olajire Oyedu~; Chi Wai Hui


    The analysis on the feedstock pyrolysis characteristic and the impacts of process parameters on pyrolysis outcomes can assist in the designing, operating and optimizing pyrolysis processes. This work aims to utilize both experimental and modelling approaches to perform the analysis on three biomass feedstocks--wood sawdust, bamboo shred and Jatropha Curcas seed cake residue, and to provide insights for the design_and operation of pyro-lysis processes. For the experimental part, the study investigated the effect of heating rate, final pyrolysis tempera- ture and sample size on pyrolysis using common thermal analysis techniques. For the modelling part, a transient mathematical model that integrates the feedstock characteristic from the experimental study was used to simulate the pyrolysis progress of selected biomass feedstock particles for reactor scenarios. The model composes of several sub-models that describe pyrolysis kinetic and heat flow, particle heat transfer, particle shrinking and reactor opera-tion. With better understanding of the effects of process conditions and feedstock characteristics on pyrolysis through both experimental and modelling studies, this work discusses on the considerations of and interrelation between feedstock size, pyrolysis energy usage, processing time and product quality for the design and operation of pyrolysis processes.

  3. Influencing Tomorrow: A Study of Emerging Influence Techniques and Their Relevance to United States Information Operations


    groups and governmental institutions; the possibility of economic loss directed at entrepreneurs; or the prospect of United States undue influence or... INFLUENCING TOMORROW: A STUDY OF EMERGING INFLUENCE TECHNIQUES AND THEIR RELEVANCE TO UNITED STATES INFORMATION OPERATIONS A...

  4. Experimental Analysis of the Input Variables’ Relevance to Forecast Next Day’s Aggregated Electric Demand Using Neural Networks

    Pablo García


    Full Text Available Thanks to the built in intelligence (deployment of new intelligent devices and sensors in places where historically they were not present, the Smart Grid and Microgrid paradigms are able to take advantage from aggregated load forecasting, which opens the door for the implementation of new algorithms to seize this information for optimization and advanced planning. Therefore, accuracy in load forecasts will potentially have a big impact on key operation factors for the future Smart Grid/Microgrid-based energy network like user satisfaction and resource saving, and new methods to achieve an efficient prediction in future energy landscapes (very different from the centralized, big area networks studied so far. This paper proposes different improved models to forecast next day’s aggregated load using artificial neural networks, taking into account the variables that are most relevant for the aggregated. In particular, seven models based on the multilayer perceptron will be proposed, progressively adding input variables after analyzing the influence of climate factors on aggregated load. The results section presents the forecast from the proposed models, obtained from real data.

  5. GA(2)LEN skin test study II: clinical relevance of inhalant allergen sensitizations in Europe

    Burbach, G J; Heinzerling, L M; Edenharter, G


    BACKGROUND: Skin prick testing is the standard for diagnosing IgE-mediated allergies. A positive skin prick reaction, however, does not always correlate with clinical symptoms. A large database from a Global Asthma and Allergy European Network (GA(2)LEN) study with data on clinical relevance...... was used to determine the clinical relevance of sensitizations against the 18 most frequent inhalant allergens in Europe. The study population consisted of patients referred to one of the 17 allergy centres in 14 European countries (n = 3034, median age = 33 years). The aim of the study was to assess...... the clinical relevance of positive skin prick test reactions against inhalant allergens considering the predominating type of symptoms in a pan-European population of patients presenting with suspected allergic disease. METHODS: Clinical relevance of skin prick tests was recorded with regard to patient history...

  6. It's All About You: an ERP study of emotion and self-relevance in discourse.

    Fields, Eric C; Kuperberg, Gina R


    Accurately communicating self-relevant and emotional information is a vital function of language, but we have little idea about how these factors impact normal discourse comprehension. In an event-related potential (ERP) study, we fully crossed self-relevance and emotion in a discourse context. Two-sentence social vignettes were presented either in the third or the second person (previous work has shown that this influences the perspective from which mental models are built). ERPs were time-locked to a critical word toward the end of the second sentence which was pleasant, neutral, or unpleasant (e.g., A man knocks on Sandra's/your hotel room door. She/You see(s) that he has agift/tray/gunin his hand.). We saw modulation of early components (P1, N1, and P2) by self-relevance, suggesting that a self-relevant context can lead to top-down attentional effects during early stages of visual processing. Unpleasant words evoked a larger late positivity than pleasant words, which evoked a larger positivity than neutral words, indicating that, regardless of self-relevance, emotional words are assessed as motivationally significant, triggering additional or deeper processing at post-lexical stages. Finally, self-relevance and emotion interacted on the late positivity: a larger late positivity was evoked by neutral words in self-relevant, but not in non-self-relevant, contexts. This may reflect prolonged attempts to disambiguate the emotional valence of ambiguous stimuli that are relevant to the self. More broadly, our findings suggest that the assessment of emotion and self-relevance are not independent, but rather that they interactively influence one another during word-by-word language comprehension.

  7. Experimental study of rare charged pion decays

    Pocanic, Dinko; van der Schaaf, Andries


    The combination of simple dynamics, small number of available decay channels, and extremely well controlled radiative and loop corrections, make charged pion decays a sensitive means for testing the underlying symmetries and the universality of weak fermion couplings, as well as for improving our understanding of pion structure and chiral dynamics. This paper reviews the current state of experimental study of the allowed rare decays of charged pions: (a) leptonic, $\\pi^+ \\to e^+\

  8. Experimental studies on transitional separated boundary layers

    Serna Serrano, José


    Separated transitional boundary layers appear on key aeronautical processes such as the flow around wings or turbomachinery blades. The aim of this thesis is the study of these flows in representative scenarios of technological applications, gaining knowledge about phenomenology and physical processes that occur there and, developing a simple model for scaling them. To achieve this goal, experimental measurements have been carried out in a low speed facility, ensuring the flow homogeneity and...

  9. Salton and Buckley’s Landmark Research in Experimental Text Information Retrieval. A Review of: Salton, G., & Buckley, C. (1990. Improving retrieval performance by relevance feedback. Journal of the American Society for Information Science, 41(4, 288–297.

    Christine F. Marton


    using both positive and negative weights based on whether the terms are coming from relevant or non-relevant documents. Yet, no new terms are actually added with negative weights; the contribution of non-relevant document terms is to modify the weighting of new terms coming from relevant documents. . . . The probabilistic model . . . is based on the distribution of query terms in relevant and non-relevant documents, This is expressed as a term weight, with the rank of each retrieved document then being the sum of the term weights for terms contained in the document that match query terms. (pp. 1-2Second, while the vector space model “has an inherent relationship between term reweighting and query expansion” (p. 2, the probabilistic model does not. Thus, query expansion is optional, but given its usefulness, various schemes have been proposed for expanding queries using terms from retrieved relevant documents.In the Salton and Buckley study 3 versions of each of the two relevance feedback methods were utilized, with two different levels of query expansion, and run on 6 different test collections. More specifically, they queried test collections that ranged in size from small to large, and that represented different domains of knowledge, including medicine and engineering with 72 experimental runs in total.Salton and Buckley examined 3 variants of the vector space model, the second and third of which were based on the first. The first model was the classic Rocchio algorithm (1971, which uses reduced document weights to modify the queries. The second model was the “Ide regular” algorithm, which reweights both relevant and non-relevant query terms (Ide, 1971. And the third model was the “Ide dec-hi” algorithm, which reweights all identified relevant items but only one retrieved nonrelevant item, the one retrieved first in the initial set of search results (Ide & Salton, 1971.As well, 3 variants of the probabilistic model developed by S.E. Robertson (Robertson

  10. Transversal Traits in Science Education Research Relevant for Teaching and Research: A Meta-Interpretative Study

    Lopes, J. Bernardino; Silva, Antonio Alberto; Cravino, Jose P.; Costa, Nilza; Marques, Luis; Campos, Carlos


    This study is a meta-interpretative analysis that focuses on research conducted and published by other researchers. Concepts central to this study include global practical relevance, curriculum design, and formative situation. We analyzed 35 studies selected from 374 published studies in the years 2000 and 2001 in three journals referenced in the…

  11. Experimental study of the chaotic waterwheel

    Rutherford, George; Erxleben, Amy; Rosa, Epaminondas, Jr.


    The chaotic waterwheel is often given as an example of a mechanical system that can exhibit chaotic behavior. Its early demonstration by Malkus and the realization that it can be modeled by the Lorenz equations has secured it a prominent place in almost every general presentation of chaos. It seems quite surprising, then, that no experimental investigations of this textbook system have ever been published. To fill this historic gap, and to initiate an experimental study of this incredibly rich dynamic system, our lab has constructed a research-grade waterwheel consisting of a vacuum-formed polycarbonate frame in which 36 cylindrical cells are mounted on an 18 inch diameter. The wheel and its axis can be tilted, and water is fed into the top of the wheel and drains out through thin tubes at the bottom of each cell. An aluminum skirt at the wheel's periphery passes through a variable gap magnet to provide magnetic braking. Angular time series data are collected with an absolute rotary encoder. The data are smoothed and angular velocity and acceleration are calculated via fast fourier transforms. The data show quasi-uniform rotation as well as periodic and chaotic motion and agree fairly well with computer simulations of the idealized wheel equations. We will discuss differences between the experimental data and the simulation predictions as well as plans for future studies.

  12. Transfer of elements relevant to nuclear fuel cycle from soil to boreal plants and animals in experimental meso- and microcosms.

    Tuovinen, Tiina S; Kasurinen, Anne; Häikiö, Elina; Tervahauta, Arja; Makkonen, Sari; Holopainen, Toini; Juutilainen, Jukka


    Uranium (U), cobalt (Co), molybdenum (Mo), nickel (Ni), lead (Pb), thorium (Th) and zinc (Zn) occur naturally in soil but their radioactive isotopes can also be released into the environment during the nuclear fuel cycle. The transfer of these elements was studied in three different trophic levels in experimental mesocosms containing downy birch (Betula pubescens), narrow buckler fern (Dryopteris carthusiana) and Scandinavian small-reed (Calamagrostis purpurea ssp. Phragmitoides) as producers, snails (Arianta arbostorum) as herbivores, and earthworms (Lumbricus terrestris) as decomposers. To determine more precisely whether the element uptake of snails is mainly via their food (birch leaves) or both via soil and food, a separate microcosm experiment was also performed. The element uptake of snails did not generally depend on the presence of soil, indicating that the main uptake route was food, except for U, where soil contact was important for uptake when soil U concentration was high. Transfer of elements from soil to plants was not linear, i.e. it was not correctly described by constant concentration ratios (CR) commonly applied in radioecological modeling. Similar nonlinear transfer was found for the invertebrate animals included in this study: elements other than U were taken up more efficiently when element concentration in soil or food was low.

  13. Experimental study of natural circulation circuit

    Lemos, Wanderley F.; Su, Jian, E-mail:, E-mail: [Coordenacao dos Programas de Pos-Graduacao de Engenharia (LASME/COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Lab. de Simulacao e Metodos Numericos; Faccini, Jose L.H., E-mail: [Instituto de Engenharia Nuclear (LTE/IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil). Lab. de Termo-Hidraulica Experimental


    This work presents an experimental study about fluid flows behavior in natural circulation, under conditions of single-phase flow. The experiment was performed through experimental thermal-hydraulic circuit built at IEN. This test equipment has performance similar to passive system of residual heat removal present in Advanced Pressurized Water Reactors (APWR). This experimental study aims to observing and analyzing the natural circulation phenomenon, using this experimental circuit that was dimensioned and built based on concepts of similarity and scale. This philosophy allows the analysis of natural circulation behavior in single-phase flow conditions proportionally to the functioning real conditions of a nuclear reactor. The experiment was performed through procedures to initialization of hydraulic feeding of primary and secondary circuits and electrical energizing of resistors installed inside heater. Power controller has availability to adjust values of electrical power to feeding resistors, in order to portray several conditions of energy decay of nuclear reactor in a steady state. Data acquisition system allows the measurement and monitoring of the evolution of the temperature in various points through thermocouples installed in strategic points along hydraulic circuit. The behavior of the natural circulation phenomenon was monitored by graphical interface on computer screen, showing the temperature evolutions of measuring points and results stored in digital spreadsheets. The results stored in digital spreadsheets allowed the getting of data to graphic construction and discussion about natural circulation phenomenon. Finally, the calculus of Reynolds number allowed the establishment for a correlation of friction in function of geometric scales of length, heights and cross section of tubing, considering a natural circulation flow throughout in the region of hot leg. (author)

  14. Experimental study on partial coherence source

    Zhao Xue Qing; Yuan Xiao; LiuJingRu; Wang Long Hua; Tang Ying; Huang, Kerson


    Partial coherence source is a key part in the laser system using echelon-free introduced spatial incoherence beam smoothing technique. Different kinds of partial coherence sources have been studied experimentally for improving the uniformity of laser intensity distribution. It is found that the source produced by excimer laser scattering on the surface of a teflon plate is ideal. The properties of this kind of source are studied. As a result, the uniformity of source beam intensity distribution, the beam spatial coherence and energy transfer efficiency of the source are obtained

  15. An experimental study of passive regenerator geometries

    Engelbrecht, Kurt; Nielsen, Kaspar Kirstein; Pryds, Nini


    this article studies the effects of regenerator geometry on performance for flat plate regenerators. This paper investigates methods of improving the performance of flat plate regenerators for use in AMR systems and studies how manufacturing variation affects regenerator performance. In order to eliminate...... experimental uncertainty associated with magnetocaloric material properties, all regenerators are made of aluminum. The performance of corrugated plates and dimpled plates are compared to traditional flat plate regenerators for a range of cycle times and utilizations. Each regenerator is built using 18...

  16. Transfer of elements relevant to nuclear fuel cycle from soil to boreal plants and animals in experimental meso- and microcosms

    Tuovinen, Tiina S., E-mail: [Department of Environmental Science, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio (Finland); Kasurinen, Anne; Häikiö, Elina [Department of Environmental Science, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio (Finland); Tervahauta, Arja [Department of Biology, University of Eastern Finland, P.O. Box FI-70211, Kuopio (Finland); Makkonen, Sari; Holopainen, Toini; Juutilainen, Jukka [Department of Environmental Science, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio (Finland)


    Uranium (U), cobalt (Co), molybdenum (Mo), nickel (Ni), lead (Pb), thorium (Th) and zinc (Zn) occur naturally in soil but their radioactive isotopes can also be released into the environment during the nuclear fuel cycle. The transfer of these elements was studied in three different trophic levels in experimental mesocosms containing downy birch (Betula pubescens), narrow buckler fern (Dryopteris carthusiana) and Scandinavian small-reed (Calamagrostis purpurea ssp. Phragmitoides) as producers, snails (Arianta arbostorum) as herbivores, and earthworms (Lumbricus terrestris) as decomposers. To determine more precisely whether the element uptake of snails is mainly via their food (birch leaves) or both via soil and food, a separate microcosm experiment was also performed. The element uptake of snails did not generally depend on the presence of soil, indicating that the main uptake route was food, except for U, where soil contact was important for uptake when soil U concentration was high. Transfer of elements from soil to plants was not linear, i.e. it was not correctly described by constant concentration ratios (CR) commonly applied in radioecological modeling. Similar nonlinear transfer was found for the invertebrate animals included in this study: elements other than U were taken up more efficiently when element concentration in soil or food was low. - Highlights: • We studied transfer of elements in boreal food chain using meso- and microcosms. • Elements related to nuclear fuel cycle and mining were examined. • Higher uptake at lower soil concentrations was observed for primary producers. • Snails took up elements mainly from food but for U also soil was an element source. • Non-linear transfer of essential elements was observed for herbivore and decomposer.

  17. Experimental percolation studies of random networks

    Feinerman, A.; Weddell, J.


    This report establishes an experimental method of studying electrically percolating networks at a higher resolution than previously implemented. This method measures the current across a conductive sheet as a function of time as elliptical pores are cut into the sheet. This is done utilizing a Universal Laser System X2-600 100 W CO2 laser system with a 76 × 46 cm2 field and 394 dpc (dots/cm) resolution. This laser can cut a random system of elliptical pores into a conductive sheet with a potential voltage applied across it and measures the current versus time. This allows for experimental verification of a percolation threshold as a function of the ellipse's aspect ratio (minor/major diameter). We show that as an ellipse's aspect ratio approaches zero, the percolation threshold approaches one. The benefit of this method is that it can experimentally measure the effect of removing small pores, as well as pores with complex geometries, such as an asterisk from a conductive sheet.

  18. Experimental Setups for Single Event Effect Studies

    N. H. Medina


    Full Text Available Experimental setups are being prepared to test and to qualify electronic devices regarding their tolerance to Single Event Effect (SEE. A multiple test setup and a new beam line developed especially for SEE studies at the São Paulo 8 UD Pelletron accelerator were prepared. This accelerator produces proton beams and heavy ion beams up to 107Ag. A Super conducting Linear accelerator, which is under construction, may fulfill all of the European Space Agency requirements to qualify electronic components for SEE.

  19. Integrating couple relationship education in antenatal education - a study of perceived relevance among expectant Danish parents.

    Axelsen, Solveig Forberg; Brixval, Carina Sjöberg; Due, Pernille; Koushede, Vibeke


    Little is known about which elements antenatal education should encompass to meet the needs of parents today. Psycho-social aspects relating to couple- and parenthood have generally not been covered in Danish antenatal education, although studies suggest that parents need this information. The aim of this study was to examine perceived relevance of couple relationship topics integrated in an antenatal programme among intervention participants in the NEWBORN trial. Our study shows that 84% of the participants found it relevant to learn about communication skills and changes in the relationship during and after pregnancy.

  20. Integrating couple relationship education in antenatal education - A study of perceived relevance among expectant Danish parents

    Axelsen, Solveig Forberg; Brixval, Carina Sjöberg; Due, Pernille;


    Little is known about which elements antenatal education should encompass to meet the needs of parents today. Psycho-social aspects relating to couple- and parenthood have generally not been covered in Danish antenatal education, although studies suggest that parents need this information. The aim...... of this study was to examine perceived relevance of couple relationship topics integrated in an antenatal programme among intervention participants in the NEWBORN trial. Our study shows that 84% of the participants found it relevant to learn about communication skills and changes in the relationship during...

  1. Can analysis of Platichthys flesus otoliths provide relevant data on historical metal pollution in estuaries? Experimental and in situ approaches

    Selleslagh, Jonathan, E-mail: [Université de Bordeaux, CNRS, UMR EPOC 5805, Station Marine d' Arcachon, place du docteur Peyneau, 33120 Arcachon (France); Echard, Aurélie [IRSTEA Centre de Bordeaux, unité EABX, 50 avenue de Verdun, 33612 Cestas (France); Pécheyran, Christophe [Université de Pau et des pays de l' Adour, CNRS, LCABIE-IPREM UMR 5254, 64053 Pau (France); Baudrimont, Magalie [Université de Bordeaux, CNRS, UMR EPOC 5805, Station Marine d' Arcachon, place du docteur Peyneau, 33120 Arcachon (France); Lobry, Jérémy; Daverat, Françoise [IRSTEA Centre de Bordeaux, unité EABX, 50 avenue de Verdun, 33612 Cestas (France)


    otoliths were complex, the concentrations were correlated with those in the water. Analysis of flounder specimens collected from 2007 to 2014 in the Gironde estuary (SW France) showed interannual variability in Pb concentrations, with higher values for fish otoliths from 2007 to 2010 than those from 2012 to 2014. This trend indicated a decrease in Pb in the Gironde estuary over the last decade, which is consistent with the results of other surveys on bivalves. Our study demonstrates that it is possible to use otolith microchemistry as a tool in assessing and retracing long-term metal pollution in estuarine systems. - Highlights: • Platichthys flesus was exposed to a cocktail of metals at realistic environmental concentrations. • Bioaccumulation of metals in tissue and otolith was linked to exposure level. • Cartography of metal in fish otolith was realized for the first time. • Otolith microchemistry of P. flesus was suggested as relevant tool to assess and retrace metal pollution. • Otoliths of P. flesus specimens collected from 2007 to 2014 in the Gironde estuary were analyzed.

  2. Experimental study of rf pulsed heating

    Laurent, L; Nantista, C; Dolgashev, V; Higashi, Y; Aicheler, M; Tantawi, S; Wuensch, W


    Cyclic thermal stresses produced by rf pulsed heating can be the limiting factor on the attainable reliable gradients for room temperature linear accelerators. This is especially true for structures that have complicated features for wakefield damping. These limits could be pushed higher by using special types of copper, copper alloys, or other conducting metals in constructing partial or complete accelerator structures. Here we present an experimental study aimed at determining the potential of these materials for tolerating cyclic thermal fatigue due to rf magnetic fields. A special cavity that has no electric field on the surface was employed in these studies. The cavity shape concentrates the magnetic field on one flat surface where the test material is placed. The materials tested in this study have included oxygen free electronic grade copper, copper zirconium, copper chromium, hot isostatically pressed copper, single crystal copper, electroplated copper, Glidcop (R), copper silver, and silver plated co...

  3. Experimental study of ore gabbro liquid immiscibility

    SANG; Zunan; XIA; Bin; ZHOU; Yongsheng; JIN; Zhenmin


    In this paper, the authors present the results of a preliminary experimental study on partial melting of fine-grained gabbro, Panzhihua, Sichuan Province, China. Experiments were conducted under (confining) pressure ranging from 450 to 500 MPa and temperature of 900-1200℃. The results show that the initial melt is distributed along grain boundaries and triple junctions. Liquid immiscibility phenomena are noted in the melt with two compositional different melt phases, i.e. matrix and sphere phases. The matrix phase is relatively rich in Si, Al and K, and is depleted in Mg, Fe, Ca, Na and Ti, whereas the sphere phase shows opposite trends. The calculation of the melt free energy indicates that the liquid immiscibility is governed by the rule of thermodynamics, as the liquid immiscibility would result in the decrease in free energy of the melt system. The field relationships suggest that the liquid immiscibility may have played an important role in the generation of ore magma of Panzhihua V-Ti magnetite ore deposit. This study thus provides experimental constraints on the mechanism of the formation of V-Ti magnetite deposite.

  4. Experimental study of diffusion charging of aerosols

    Pui, D.Y.H.


    The electrical charging of aerosol particles by unipolar gaseous ions was studied theoretically and experimentally. The primary objective of the study was to make precise determinations of the aerosol particle charge under various conditions of charging and to compare the experimental results with those predicted by theory. Experiments were performed using monodisperse oleic acid aerosols generated by a vibrating orifice generator, monodisperse NaCl and DOP (di-octyl phthalate) aerosols generated by an electrostatic classification method, and sulfuric acid aerosols generated by the photo-chemical conversion of gaseous SO/sub 2/ in the smog chamber. The experiments covered a particle size range of 0.0075 to 5.04 diameter. The corresponding range in Knudsen number (Kn = lambda/sub i//a, lambda/sub i/ = mean free path of ions, a = particle radius) was from 0.0056 to 3.86. The charging parameter, n/sub 0/t, was varied between 2.56 x 10/sup 6/ to 5.1 x 10/sup 7/ ion-s/cc, where n/sub 0/ is the concentration of ions and t is the charging time. Comparisons of the results with available aerosol charging theories indicate that there is reasonable agreement between the theory and experiment in the continuum regime (Kn << 1) where the classical Fuchs--Pluvinage equation is expected to apply. However, in the free molecular (Kn >> 1) and the transition regimes (Kn approx. or equal to 1), where the ion mean free path is no longer small in comparison with particle size, there is considerable discrepancy between the experimental data and available charging theories. A semi-empirical equation was developed which agrees well with the experimental data over the entire range of particle size and charging parameters covered in the experiments. Theoretical results are presented showing the distribution of charges on the particles as a function of particle size and the charging parameter n/sub 0/t. 70 figures, 24 tables, 112 references. (auth)

  5. Ecological relevance of biomarkers in monitoring studies of macro-invertebrates and fish in Mediterranean rivers.

    Colin, Nicole; Porte, Cinta; Fernandes, Denise; Barata, Carlos; Padrós, Francesc; Carrassón, Maite; Monroy, Mario; Cano-Rocabayera, Oriol; de Sostoa, Adolfo; Piña, Benjamín; Maceda-Veiga, Alberto


    Mediterranean rivers are probably one of the most singular and endangered ecosystems worldwide due to the presence of many endemic species and a long history of anthropogenic impacts. Besides a conservation value per se, biodiversity is related to the services that ecosystems provide to society and the ability of these to cope with stressors, including climate change. Using macro-invertebrates and fish as sentinel organisms, this overview presents a synthesis of the state of the art in the application of biomarkers (stress and enzymatic responses, endocrine disruptors, trophic tracers, energy and bile metabolites, genotoxic indicators, histopathological and behavioural alterations, and genetic and cutting edge omic markers) to determine the causes and effects of anthropogenic stressors on the biodiversity of European Mediterranean rivers. We also discuss how a careful selection of sentinel species according to their ecological traits and the food-web structure of Mediterranean rivers could increase the ecological relevance of biomarker responses. Further, we provide suggestions to better harmonise ecological realism with experimental design in biomarker studies, including statistical analyses, which may also deliver a more comprehensible message to managers and policy makers. By keeping on the safe side the health status of populations of multiple-species in a community, we advocate to increase the resilience of fluvial ecosystems to face present and forecasted stressors. In conclusion, this review provides evidence that multi-biomarker approaches detect early signs of impairment in populations, and supports their incorporation in the standardised procedures of the Water Frame Work Directive to better appraise the status of European water bodies.

  6. Experimental study of oxidative DNA damage

    Loft, S; Deng, Xiaohong; Tuo, J


    compounds have been studied in animal experiments mainly in rats and mice, and generally with measurement of 8-oxodG with HPLC-EC. A large number of well-known carcinogens induce 8-oxodG formation in liver and/or kidneys. Moreover several animal studies have shown a close relationship between induction...... of the use of 2-nitropropane as a model for oxidative DNA damage relate particularly to formation of 8-aminoguanine derivatives that may interfere with HPLC-EC assays and have unknown consequences. Other model compounds for induction of oxidative DNA damage, such as ferric nitriloacetate, iron dextran......, potassium bromate and paraquat, are less potent and/or more organ specific. Inflammation and activation of an inflammatory response by phorbol esters or E. coli lipopolysaccharide (LPS) induce oxidative DNA damage in many target cells and enhance benzene-induced DNA damage in mouse bone marrow. Experimental...

  7. Experimental and computational thermochemical study of oxindole

    Miranda, Margarida S., E-mail: msmirand@fc.up.p [Centro de Investigacao em Quimica, Departamento de Quimica e Bioquimica, Faculdade de Ciencias da Universidade do Porto, Rua do Campo Alegre, 687, P-4169-007 Porto (Portugal); Centro de Geologia da Universidade do Porto, Rua do Campo Alegre, 687, P-4169-007 Porto (Portugal); Matos, M. Agostinha R., E-mail: marmatos@fc.up.p [Centro de Investigacao em Quimica, Departamento de Quimica e Bioquimica, Faculdade de Ciencias da Universidade do Porto, Rua do Campo Alegre, 687, P-4169-007 Porto (Portugal); Morais, Victor M.F., E-mail: vmmorais@icbas.up.p [Centro de Investigacao em Quimica, Departamento de Quimica e Bioquimica, Faculdade de Ciencias da Universidade do Porto, Rua do Campo Alegre, 687, P-4169-007 Porto (Portugal); Instituto de Ciencias Biomedicas Abel Salazar, ICBAS, Universidade do Porto, P-4099-003 Porto (Portugal); Liebman, Joel F., E-mail: jliebman@umbc.ed [Department of Chemistry and Biochemistry, University of Maryland, Baltimore County, Baltimore, MD 21250 (United States)


    An experimental and computational thermochemical study was performed for oxindole. The standard (p{sup 0}=0.1MPa) molar enthalpy of formation of solid oxindole was derived from the standard molar energy of combustion, in oxygen, at T = 298.15 K, measured by static bomb combustion calorimetry. The respective standard molar enthalpy of sublimation, at T = 298.15 K, was measured by Calvet microcalorimetry. The standard molar enthalpy of formation in the gas phase was derived as -(66.8 {+-} 3.2) kJ . mol{sup -1}. Density functional theory calculations with the B3LYP hybrid functional and the 6-31G* and 6-311G** sets have also been performed in order to obtain the most stable conformation of oxindole. A comparison has been made between the structure of oxindole and that of the related two-ring molecules: indoline and 2-indanone and the one-ring molecules: pyrrolidine and 2,3-dihydropyrrole. The G3(MP2)//B3LYP method and appropriate reactions were used to obtain estimates of the standard molar enthalpy of formation of oxindole in the gas phase, at T = 298.15 K. Computationally obtained estimates of the enthalpy of formation of oxindole are in very good agreement with the experimental gas phase value. The aromaticity of oxindole was evaluated through the analysis of the nucleus independent chemical shifts (NICS) obtained from the B3LYP/6-311G** wave functions.

  8. Experimental Study on Unconfined Vapor Cloud Explosion

    毕明树; ABULITI; Abudula


    An experimental system was setup to study the pressure field of unconfined vapor cloud explosions.The semi-spherical vapor clouds were formed by slotted 0.02mm polyethylene film.In the Center of the cloud was an ignition electrode that met ISO6164"Explosion protection System" and NFPA68 "Guide for Venting of Deflagrations". A data-acquisition system,with dymame responding time less than 0.001s with 0.5% accuracy,recorded the pressure-time diagram of acetylene-air mixture explosion with stoichiometrical ratio.The initial cloud diameters varied from 60cm to 300cm.Based on the analysis of experimental data,the quantitative relationship is obtained for the cloud explosion pressure,the cloud radius and the distance from ignition point .Present results provide a useful way to evaluate the building damage caused by unconfined vapor cloud explosions and to determine the indispensable explosion grade in the application of multi-energy model.

  9. An Experimental Study of Soft Lubrication

    Wu, Qianhong; Gacka, Thomas; Nathan, Rungun; Wu, Li-Zhu; Cbmss Team


    Lift generation in soft porous media, as a planing surface glides over it, is a new topic in porous media flow with superior potential for lubrication and squeeze damping. This paper presents the first experimental study of this phenomenon. The experimental setup consists of a running conveyer belt covered with a soft porous sheet, and a stationary instrumented inclined planar upper board. Twelve pressure transducers mounted on the upper board captured the pore pressure generation, while a load cell was used to capture the total lifting force, arising from both the pore pressure and the compression of the solid fibers. One finds that the pore pressure distribution is consistent with theoretical predictions (Feng and Weinbaum, JFM, 2000; Wu et al., MSSE, 2006, 2011), and depends on the running belt velocity, U, the mechanical properties of the porous material, and the compression ratios of the porous layer. For a typical trial (h2/h1=5,h2/h0=1, U=3.8 m/s, where h2, h1, and h0 are the leading edge, trailing edge, and undeformed porous layer thicknesses, respectively), 68% of the lifting force was generated by the pore pressure. It conclusively demonstrates the validity of using soft porous materials for super lubrication. applications. Villanova Cellular Biomechanics and Sports Science Laboratory.

  10. Metabolic Desynchronization in Critical Conditions: Experimental Study

    G. V. Livanov


    Full Text Available Objective. To conduct an experimental study of the impact of the time of administration of succinic acid preparations on central nervous system (CNS function and gas exchange while simulating metabolic therapy for severe poisoning by ethyl alcohol. The study was performed on 74 male albino rats weighing 140—180 g. Acute severe and very severe intoxication was simulated, by intraabdominally administering 30% ethanol to the rats. Cytoflavin was used to simulate experimental therapy. The rate of gas exchange was estimated by the oxygen uptake determined by the closed chamber method in a Regnault apparatus (Germany. Spontaneous bioelectrical activity was recorded in the frontooccipital lead by the routine procedure. External pain stimulation and rhythmical photostimulation were employed to evaluate cerebral responsiveness. Heterodirectional EEG changes in the «early» and «late» administration of succinate were not followed by the similar alterations of gas exchange: oxygen consumption in both the «early» and «late» administration of succinate remained significantly lower than in the control animals. With the late administration of succinate to the animals with mixed (toxic and hypoxic coma, the so-called discrepancy between the noticeably increased energy production and brutally diminished metabolism occurred. It may be just the pathological mechanism that was the basis for higher mortality in the late succinate administration group. The findings and their analysis make it possible to advance a hypothesis that succinate may cause metabolic desynchronization if activation of metabolic processes takes place under severe tissue respiratory tissue depression. In these cases, there is a severe damage to tissue and chiefly the brain. This manifests itself as EEG epileptiform activity splashes preceding the animals’ death. Therefore, resuscitation aimed at restoring the transport of oxygen and its involvement in tissue energy processes should

  11. Study on Immune Relevant Vector Machine Based Intelligent Fault Detection and Diagnosis Algorithm

    Zhong-hua Miao


    Full Text Available An immune relevant vector machine (IRVM based intelligent classification method is proposed by combining the random real-valued negative selection (RRNS algorithm and the relevant vector machine (RVM algorithm. The method proposed is aimed to handle the training problem of missing or incomplete fault sampling data and is inspired by the “self/nonself” recognition principle in the artificial immune systems. The detectors, generated by the RRNS, are treated as the “nonself” training samples and used to train the RVM model together with the “self” training samples. After the training succeeds, the “nonself” detection model, which requires only the “self” training samples, is obtained for the fault detection and diagnosis. It provides a general way solving the problems of this type and can be applied for both fault detection and fault diagnosis. The standard Fisher's Iris flower dataset is used to experimentally testify the proposed method, and the results are compared with those from the support vector data description (SVDD method. Experimental results have shown the validity and practicability of the proposed method.

  12. Perceptions of unfairness in price increases: an experimental study

    Verônica Feder Mayer


    Full Text Available This experimental study investigates antecedents and consequences of perceptions of price unfairness in a price increase situation. The proposed theoretical model states that consumer dependence on the service provider as well as the relevance the consumer attributes to the service (for the consumer's life will affect his/her degree of (a unfairness price perception, (b anger, and (c intention to complain and retaliate. The results support all the hypotheses specified in the model. The findings not only indicate that some situations of unfairness price perception lead to stronger emotions and more dramatic reactions from consumers, but also allow us to predict which situations of perceived unfairness offer greater risks and have greater potential for conflict.

  13. Studies relevant to the catalytic activation of carbon monoxide. Technical progress report, September 1991

    Ford, P.C.


    Research activity during the 1991--1992 funding period has been concerned with the following topics relevant to carbon monoxide activation. (1) Exploratory studies of water gas shift catalysts heterogenized on polystyrene based polymers. (2) Mechanistic investigation of the nucleophilic activation of CO in metal carbonyl clusters. (3) Application of fast reaction techniques to prepare and to investigate reactive organometallic intermediates relevant to the activation of hydrocarbons toward carbonylation and to the formation of carbon-carbon bonds via the migratory insertion of CO into metal alkyl bonds.

  14. Cognitive network structure: an experimental study

    Guazzini, Andrea; Bagnoli, Franco; Carletti, Timoteo; Grotto, Rosapia Lauro


    In this paper we present first experimental results about a small group of people exchanging private and public messages in a virtual community. Our goal is the study of the cognitive network that emerges during a chat seance. We used the Derrida coefficient and the triangle structure under the working assumption that moods and perceived mutual affinity can produce results complementary to a full semantic analysis. The most outstanding outcome is the difference between the network obtained considering publicly exchanged messages and the one considering only privately exchanged messages: in the former case, the network is very homogeneous, in the sense that each individual interacts in the same way with all the participants, whilst in the latter the interactions among different agents are very heterogeneous, and are based on "the enemy of my enemy is my friend" strategy. Finally a recent characterization of the triangular cliques has been considered in order to describe the intimate structure of the network. E...

  15. Experimental studies on ozonation of ethylenethiourea

    Xinyu Dong; Junwang Meng; Bo Yang; Yang Zhang; Jie Gan; Xi Shu; Jinian Shu


    The experimental study on ozonation of ethylenethiourea (ETU) is conducted. The reaction of gas-phase ETU with 0.63 × l06 mol/L ozone is carried out in a 200-L reaction chamber. The secondary organic aerosol (SOA) resulted from the ozonation of gas-phase ETU is observed with a scanning mobility particle size (SMPS). The rapid exponential growth of SOA reveals that the atmospheric lifetime of ETU vapor towards ozone reaction is less than four days. The ozonation of dry ETU particles, ETU-contained water droplets and ETU aqueous solution is investigated with a vacuum ultraviolet photoionization aerosol time-of-flight mass spectrometer (VUVATOFMS). The formation of 2-imidazoline is observed in the ozonation of dry ETU particles and ETU-contained water droplets. The formation of 2-imidazoline and ethylenerea is observed in the ozonation of ETU aqueous solution.

  16. [Endodontics in horses. An experimental study].

    Garcia, F; Sanromán, F; Llorens, M P


    A total of 44 experimental endodontic treatments were performed in incisors of eight horses of different ages. Four different endodontic pastes were used: Cloropercha, AH26 De Trey, Eugenol-Endometasone, and Universal N2. Gutta-percha points were also included in the last two treatments. Access to the pulp cavity of incisors was gained through their vestibular and occlusal faces. Holes drilled in vestibular faces were sealed with composite and those drilled in occlusal faces were sealed with Amalgama. Animals were observed during eighteen months at least after endodontics. Radiographic controls were done just after surgery and before slaughtering. Treated incisors and alveoli were studied histopathologically. During the experiment all animals were in good condition. They ate apparently without trouble, and neither clinical nor radiological signs were present.

  17. Lipid peroxidation in experimental uveitis: sequential studies.

    Goto, H; Wu, G S; Chen, F; Kristeva, M; Sevanian, A; Rao, N A


    Previously we have detected the occurrence of retinal lipid peroxidation initiated by phagocyte-derived oxygen radicals in experimental autoimmune uveitis (EAU). In the current studies, the confirmation of inflammation-mediated lipid peroxidation was proceeded further to include measurement of multiple parameters, including conjugated dienes, ketodienes, thiobarbituric acid reactive substances and fluorescent chromolipids. The assay for myeloperoxidase, a measure for the number of polymorphonuclear leukocytes in the inflammatory sites was also carried out. The levels of all these parameters were followed through the course of EAU development. The sequential evaluation of histologic changes using both light and electron microscopy was also carried out and the results were correlated with lipid peroxidation indices. These data suggest that the retinal lipid peroxidation plays a causative role in the subsequent retinal degeneration.

  18. A Solution Study of Silica Condensation and Speciation With relevance to in vitro investigations of biosilicification

    Belton, David J.; Deschaume, Olivier; Patwardhan, Siddharth V.; Perry, Carole C.


    With both mild synthesis conditions, a high level of organisation and functionality, biosilicas constitute a source of wonder and inspiration for both materials scientists and biologists. In order to understand how such biomaterials are formed and to apply this knowledge to the generation of novel bioinspired materials, a detailed study of the materials, as formed under biologically relevant conditions, is required. In this contribution, data from a detailed study of silica speciation and condensation using a model bio-inspired silica precursor (silicon catechol complex, SCC) is presented. The silicon complex quickly and controllably dissociates under neutral pH conditions to well-defined, metastable solutions of orthosilicic acid. The formation of silicomolybdous (blue) complexes was used to monitor and study different stages of silicic acid condensation. In parallel, the rates of silicomolybdic (yellow) complex formation, with mathematical modelling of the species present was used to follow the solution speciation of polysilicic acids. The results obtained from the two assays correlate well and monomeric silicic acid, trimeric silicic acids and different classes of oligomeric polysilicic acids and silica nuclei can be identified and their periods of stability during the early stages of silica condensation measured. For experiments performed at a range of temperatures (273–323K) an activation energy of 77kJ·mol−1 was obtained for the formation of trimers. The activation energies for the forward and reverse condensation reactions for addition of monomers to polysilicic acids (273–293 ± 1K) were 55.0 and 58.6kJ·mol−1 respectively. For temperatures above 293K, these energies were reduced to 6.1 and 7.3 kJ·mol−1 indicating a probable change in the prevailing condensation mechanism. The impact of pH on the rates of condensation were measured. There was a direct correlation between the apparent third order rate constant for trimer formation and pH (4.7–6

  19. Experimental and theoretical study of reflux condensation

    Bakke, Knut


    This thesis studies the separation of gas mixtures in a reflux condenser. also called a dephlegmator. Reflux condensation is separation of a gas mixture, in reflux flow with condensing liquid, under continuous heat removal. A numerical model of a dephlegmator for binary mixtures was developed. The model may readily be extended to multi-component mixtures, as the solution method is based on a matrix solver. Separation of a binary mixture in a reflux condenser test rig is demonstrated. The test facility contains a single-tube test section that was designed and built as part of the project. Test mixtures of propane and n-butane were used, and a total of 15 experiments are reported. Limited degree of separation was achieved due to limited heat transfer area and narrow boiling point range of the test mixture. The numerical model reproduces the experimental data within reasonable accuracy. Deviation between calculated and measured properties is less than 6% of the measured temperature and less than 5% of the measured flow rate. The model is based on mechanistic models of physical processes and is not calibrated or tuned to fit the experimental data. The numerical model is applied to a number of separation processes. These case studies show that the required heat transfer area increases rapidly with increments in top product composition (light component). Flooding limits the amount of reflux liquid. The dephlegmator is suitable for separation of feed mixtures that are rich in light components. The gliding temperature in the dephlegmation process enables utilization of top product as refrigerant, with subsequent energy saving as a result. 61 refs., 50 figs., 34 tabs.

  20. Relevance of animal studies in regulatory toxicology : current approaches and future opportunities

    Sandt, J.J.M. van de; Feron, V.J.


    With rapidly increasing knowledge of toxicological processes, the scientific value and relevance of toxicity studies for risk assessment must be re-evaluated. In this paper, it is proposed that the rigid risk evaluation currently required should be replaced by a more flexible, case-by-case approach,

  1. Clinical relevance of studies on the accuracy of visual inspection for detecting caries lesions

    Gimenez, Thais; Piovesan, Chaiana; Braga, Mariana M


    the clinical relevance and methodological quality of studies on the accuracy of visual inspection for assessing caries lesions. Two independent reviewers searched several databases through July 2013 to identify papers/articles published in English. Other sources were checked to identify unpublished literature...

  2. An experimental study of nerve bypass graft

    XU Jie; LI Xue-shi


    Objective: To study the use of a nerve "bypass" graft as a possible alternative to neurolysis or segmental resection with interposition grafting in the treatment of neuroma-in-continuity. Methods: A sciatic nerve crush injury model was established in the Sprague-Dawley rat by compression with a straight hemostatic forceps. Epineurial windows were created proximal and distal to the injury site. An 8-mm segment of radial nerve was harvested and coaptated to the sciatic nerve at the epineurial window sites proximal and distal to the compressed segment (bypass group). A sciatic nerve crush injury without bypass served as a control. Nerve conduction studies were performed over an 8-week period. Sciatic nerves were then harvested and studied under transmission electron microscopy. Myelinated axon counts were obtained. Results: Nerve conduction velocity was significantly faster in the bypass group than in the control group at 8 weeks (63.57 m/s±5.83 m/s vs. 54.88 m/s±4.79m/s, P<0.01). Myelinated axon counts in distal segments were found more in the experimental sciatic nerve than in the control sciatic nerve. Significant axonal growth was noted in the bypass nerve segment itself. Conclusion: Nerve bypass may serve to augment peripheral axonal growth while avoiding further loss of the native nerve.

  3. Experimental studies of biomass gasification with air

    Huili Liu; Jianhang Hu; Hua Wang; Chao Wang; Juanqin Li


    In this work,experimental studies of biomass gasification under different operating conditions were carried out in an updraft gasifier combined with a copper slag reformer.The influence of gasification temperature,equivalence ratio (ER) and copper slag catalyst addition on gas production and tar yield were investigated.The experimental results showed that the content of H2 and CO,gas yield and LHV increased,while the tar yield and the content of CO2,CH4 and C2Hx in the gas product decreased with the temperature.At 800 ℃,with the increase of ER,the LHV,the tar yield and the content of H2,CO,CH4 and C2Hx in gas products decreased,while the gas yield and the content of CO2 increased.Copper slag was introduced into the secondary reformer for tar decomposition.The Fe3O4 phase in the fresh copper slag was reduced to FeO (Fe2+) and metallic Fe by the gas product.Fe species (FeO and metallic Fe) acted as the active sites for tar catalytic decomposition.The catalytic temperature had a significant influence on tar conversion and the composition of the gas product.Typically,the tar conversion of about 17%-54% could be achieved when the catalytic temperature was varied from 750 to 950 ℃.Also,the content of H2 and CO increased with the catalytic temperature,while that of CO2,CH4 and C2Hx in the gas product decreased.It was demonstrated that copper slag was a good catalyst for upgrading the gas product from biomass gasification.

  4. Attentional bias in snus users: an experimental study.

    Rune Aune Mentzoni

    Full Text Available The use of nicotine in the form of "snus" is substantial and increasing in some geographic areas, in particular among young people. It has previously been suggested that addictions may operate through a mechanism of attentional bias, in which stimuli representative of the dependent substance increase in salience, thus increasing the addictive behavior. However, this hypothesis has not been tested for the case of snus. The current experiment used a modified Stroop task and a dot-probe task to investigate whether 40 snus users show an attentional bias towards snus-relevant stimuli, compared to 40 non-snus users. There were no significant differences between the two groups on reaction times or accuracy on either Stroop or dot-probe task, thus failing to show an attentional bias towards snus-relevant stimuli for snus users. This could imply that other mechanisms may contribute to maintenance of snus use than for other addictions. However, this is the first experimental study investigating attentional bias in snus users, and more research is warranted.

  5. Analysis of experimental studies on gully erosion: a global review

    Castillo, Carlos; Gómez, Jose A.


    Research on gully erosion has increased significantly in the last decades. Despite the growing interest on the topic, relevant knowledge gaps still remain a challenge for gully erosion researchers (Poesen, 2011). Moreover, many of these studies are mainly descriptive, with little quantitative data allowing a comparison of the severity of the processes among different environments and conditions. The aim of this communication is to analyse the available experimental data in gully erosion literature involving quantitative information from the Web of Science datasets. Our objective is to investigate relevant trends of this type of erosion on the world scale. We have evaluated the role of gully erosion in the overall soil losses as well as the magnitude of the morphological variables. Also, we analysed the characteristics of image-based and field surveys regarding the technique employed, duration and data collection frequency. In this communication, we intend to provide insights on the evolution of gully erosion research up to the present moment in order to gain perspectives on the design of future efforts in the topic. References Poesen, J. 2011. Challenges in gully erosion research. Landform Analysis, Vol. 17: 5-9.

  6. The false memory syndrome: experimental studies and comparison to confabulations.

    Mendez, M F; Fras, I A


    False memories, or recollections that are factually incorrect but strongly believed, remain a source of confusion for both psychiatrists and neurologists. We propose model for false memories based on recent experimental investigations, particularly when analyzed in comparison to confabulations, which are the equivalent of false memories from neurological disease. Studies using the Deese/Roedinger-McDermott experimental paradigm indicate that false memories are associated with the need for complete and integrated memories, self-relevancy, imagination and wish fulfillment, familiarity, emotional facilitation, suggestibility, and sexual content. In comparison, confabulations are associated with the same factors except for emotional facilitation, suggestibility, and sexual content. Both false memories and confabulations have an abnormal sense of certainty for their recollections, and neuroanatomical findings implicate decreased activity in the ventromedial frontal lobe in this certainty. In summary, recent studies of false memories in comparison to confabulations support a model of false memories as internally-generated but suggestible and emotionally-facilitated fantasies or impulses, rather than repressed memories of real events. Furthermore, like confabulations, in order for false memories to occur there must be an attenuation of the normal, nonconscious, right frontal "doubt tag" regarding their certainty.

  7. Studies of the surface reactivity of metal oxyhydroxides and sulfides with relevance to environmental chemistry

    Pierre-Louis, Andro-Marc

    With the benefits of an ever increasing advance of industrialization around the globe come formidable environmental problems. Three environmental problems that have relevance to the research described in this thesis are the 1) buildup of atmospheric CO2 gas through the burning of fossil fuels, 2) eutrophication of aquatic systems, and 3) the acidification of environments from acid mine drainage (AMD) resulting from coal-mining activities. In particular research is presented in this thesis that investigated the surface chemistry of CO2 and phosphate (PO43-) on a suite of environmentally relevant iron oxyhydroxide materials and the chemistry of phospholipid molecules on environmentally relevant iron sulfide surfaces to suppress AMD. To develop a microscopic understanding of the surface chemistry of the different systems, an array of experimental and computational techniques were used in the research. Techniques included X-ray photoelectron spectroscopy, atomic adsorption, X-ray diffraction, scanning transmission microscopy with electron dispersive X-ray spectroscopy (STEM/EDS), ion chromatography (IC), and attenuated total reflectance Fourier transform Infrared (ATR-FTIR). Results from the latter technique were interpreted with the aid of density function theory (DFT) calculations. Iron oxyhydroxides, which consisted of ferrihydrite (FeOOH), goethite (α-FeOOH), ferrimagnetic ferrihydrite (FerriFh), and aluminum-doped iron oxyhydroxide (content from 0-100 mol%) were synthesized and studied before and after exposure to gaseous CO2, CO32-, and PO43- species. FeOOH and mixed Al/Fe oxyhydroxide surfaces showed high affinities for the formation of carbonate and bicarbonate species upon exposure to gaseous CO2. Within the Al/Fe oxyhydroxide circumstance, a low Al level of incorporation in the iron oxyhydroxide structure caused a slight increase in surface area and increase in the amount of oxyanion (e.g., CO32- or PO43-) adsorption up to an Al level of 30 mol%. Significant

  8. Experimental methods in studying child language acquisition.

    Ambridge, Ben; Rowland, Caroline F


    This article reviews the some of the most widely used methods used for studying children's language acquisition including (1) spontaneous/naturalistic, diary, parental report data, (2) production methods (elicited production, repetition/elicited imitation, syntactic priming/weird word order), (3) comprehension methods (act-out, pointing, intermodal preferential looking, looking while listening, conditioned head turn preference procedure, functional neuroimaging) and (4) judgment methods (grammaticality/acceptability judgments, yes-no/truth-value judgments). The review outlines the types of studies and age-groups to which each method is most suited, as well as the advantage and disadvantages of each. We conclude by summarising the particular methodological considerations that apply to each paradigm and to experimental design more generally. These include (1) choosing an age-appropriate task that makes communicative sense (2) motivating children to co-operate, (3) choosing a between-/within-subjects design, (4) the use of novel items (e.g., novel verbs), (5) fillers, (6) blocked, counterbalanced and random presentation, (7) the appropriate number of trials and participants, (8) drop-out rates (9) the importance of control conditions, (10) choosing a sensitive dependent measure (11) classification of responses, and (12) using an appropriate statistical test. WIREs Cogn Sci 2013, 4:149-168. doi: 10.1002/wcs.1215 For further resources related to this article, please visit the WIREs website. The authors declare no conflict of interest. Copyright © 2013 John Wiley & Sons, Ltd.

  9. Study of higher excited states of some polyatomic molecules relevant for plasma physics and environment

    Marinkovic, B P, E-mail: [Institute of Physics, Belgrade 11080, Pregrevica 118 (Serbia) and College for Electrical Engineering and Computing, Belgrade 11010, Vojvode Stepe 283 (Serbia)


    Studies of higher excited states of some polyatomic molecules relevant for plasma physics and environment have been presented. Spectra of chlorofluorocarbons are discussed together with their influence on ozone layer depletion and global warming. Tetrahydrofuran molecule was studied by photoabsorption and electron energy loss spectroscopy while the states are assigned following extensive ab initio calculations. Nitrous oxide and hydrogen sulphide spectra are discussed in terms of identifying valence and Rydberg character of excited states.

  10. A Solution Study of Silica Condensation and Speciation With relevance to in vitro investigations of biosilicification

    Belton, David J.; Deschaume, Olivier; Patwardhan, Siddharth V.; Perry, Carole C.


    With both mild synthesis conditions, a high level of organisation and functionality, biosilicas constitute a source of wonder and inspiration for both materials scientists and biologists. In order to understand how such biomaterials are formed and to apply this knowledge to the generation of novel bioinspired materials, a detailed study of the materials, as formed under biologically relevant conditions, is required. In this contribution, data from a detailed study of silica speciation and con...

  11. Experimental and Theoretical Studies of Atmosphereic Inorganic Chlorine Chemistry

    Sander, Stanley P.; Friedl, Randall R.


    Over the last five years substantial progress has been made in defining the realm of new chlorine chemistry in the polar stratosphere. Application of existing experimental techniques to potentially important chlorine-containing compounds has yielded quantitative kinetic and spectroscopic data as well as qualitative mechanistic insights into the relevant reactions.

  12. Theoretical studies of oxides relevant to the combustion of fossil fuels

    Hicks, Jason Michael

    : adsorption isotherms, Gibbs free energy, enthalpy, entropy and desorption free energy. It was found that, when the maximum loading was compared to the regeneration costs, IRMOF-10 had the best performance, followed by IRMOF-8 then IRMOF-1. During the combustion of coal, not only is CO2 produced, but also the trace elements of arsenic and selenium escape into the environment though this process. Both arsenic and selenium are known to have a harmful effects on the environment and human health. Arsenic is also known to poison the catalytic converter used in selective catalytic reduction of NOx . These trace elements have been found on fly ash or in the hot flue gases released into the atmosphere. In flue gases they most often exist as oxides. There have been many experimental and a few theoretical studies on the monomeric oxides, AsOx and SeOx, where x = 1, 2, or 3. However, little is known concerning the corresponding dimeric oxides, As2Ox and Se2Ox, where x = 3 or 5, though these compounds are expected from their similarities to nitrogen and sulfur chemistry, respectively. From an experimental perspective, they are very challenging to study due to the high temperatures, complex environments and low concentrations needed for a direct study of the form and structures of the dimeric oxides. From a theoretical perspective, they can be challenging to study due to their multireference character and the need for both dynamic and non-dynamic electron correlation due to bonds forming and breaking during isomerization. However, high level multireference ab initio methods which account for both dynamic and non-dynamic electron correlation can be used. In the work contained in this thesis, GVVPT2 and CR-CC(2,3) were used to study the relative stabilities of all relevant isomers and transition states of As2Ox and Se2Ox. The structures used where generated through DFT using the B3LYP functional. Not only were plausible stationary points located for all species, it was further confirmed

  13. An experimental investigation of stimulated Brillouin scattering in laser-produced plasmas relevant to inertial confinement fusion

    Bradley, K.S. [Univ. of California, Davis, CA (US)


    Despite the apparent simplicity of controlled fusion, there are many phenomena which have prevented its achievement. One phenomenon is laser-plasma instabilities. An investigation of one such instability, stimulated Brillouin scattering (SBS), is reported here. SBS is a parametric process whereby an electromagnetic wave (the parent wave) decays into another electromagnetic wave and an ion acoustic wave (the daughter waves). SBS impedes controlled fusion since it can scatter much or all of the incident laser light, resulting in poor drive symmetry and inefficient laser-plasma coupling. It is widely believed that SBS becomes convectively unstable--that is, it grows as it traverses the plasma. Though it has yet to be definitively tested, convective theory is often invoked to explain experimental observations, even when one or more of the theory`s assumptions are violated. In contrast, the experiments reported here not only obeyed the assumptions of the theory, but were also conducted in plasmas with peak densities well below quarter-critical density. This prevented other competing or coexisting phenomena from occurring, thereby providing clearly interpretable results. These are the first SBS experiments that were designed to be both a clear test of linear convective theory and pertinent to controlled fusion research. A crucial part of this series of experiments was the development of a new instrument, the Multiple Angle Time Resolving Spectrometer (MATRS). MATRS has the unique capability of both spectrally and temporally resolving absolute levels of scattered light at many angles simultaneously, and is the first of its kind used in laser-plasma experiments. A detailed comparison of the theoretical predictions and the experimental observations is made.

  14. Experimental Study of Olivine-rich Troctolites

    Mu, S.; Faul, U.


    This experimental study is designed to complement field observations of olivine-rich troctolites in ophiolites and from mid-ocean ridges. The olivine-rich troctolites are characterized by high volume proportion of olivine with interstitial plagioclase and clinopyroxene. Typically the clinopyroxene occurs in the form of few large, poikilitic grains. The primary purpose of this study is to investigate the effects of cooling process on the geometry of the interstitial phases (clinopyroxene and plagioclase). Experiments are conducted in a piston cylinder apparatus by first annealing olivine plus a basaltic melt with a composition designed to be in equilibrium with four phases at ~ 1 GPa and 1250ºC. Initially, we anneal the olivine-basalt aggregates at 1350 °C and 0.7 GPa for one week to produce a steady state microstructure. At this temperature only olivine and minor opx are present as crystalline phases. We then cool the samples over two weeks below their solidus temperature, following different protocols. The post-run samples are sectioned, polished, and imaged at high resolution and analyzed by using a field emission SEM. Initial observations show that under certain conditions clinopyroxene nucleates distributed throughout the aggregate at many sites, forming relatively small, rounded to near euhedral grains. Under certain conditions few cpx grains nucleate and grow with a poikilitic shape, partially or fully enclosing olivine grains, as is observed in natural samples. As for partially molten aggregates quenched form the annealing temperature, the microstructure will be characterized by tracing phase boundaries on screen by using ImageJ software. The geometry of the interstitial phases will be quantified by determining the grain boundary wetness, in this case the ratio of the length of polyphase to single phase (olivine-olivine) boundaries. Compositional data will also be used to study the change in major element compositions before and after the cooling process.

  15. Experimental study of finite Larmor radius effects

    Struve, K.W.


    Linear Z-pinches in Ar, Kr, Xe, N/sub 2/, and He are experimentally studied in regimes where strong finite Larmor radius effects could provide a significant stabilizing effect. Scaling arguments show that for deuterium such a pinch has an electron line density of order 2 x 10/sup 15//cm. For higher Z plasmas a higher line density is allowed, the exact value of which depends on the average ion charge. The pinch is formed by puffing gas axially through the cathode towards the anode of an evacuated pinch chamber. When the gas reaches the anode, the pinch bank is fired. The pinch current rises in 2 to 3 to a maximum of 100 to 200 kA. The pinch bank capacitance is 900, and the external inductance is 100 nH. Additionally, the bank is fused to increase dI/dt. The primary diagnostics are a framing camera, a spatially resolved Mach-Zehnder interferometer, and X-ray absorption.

  16. Experimental studies of fiber concrete creep

    Korneeva Irina


    Full Text Available The results of two-stage experimental studies of the strength and deformation characteristics of fibrous concrete reinforced with steel fiber. In the experiments we used steel fiber with bent ends, which practically does not form "hedgehogs", which allows to achieve an even distribution of the fiber by volume. At the first stage, the cube and prismatic strength, deformability at central compression, a number of special characteristics are determined: water absorption, frost resistance, abrasion; the optimal percentage of fiber reinforcement and the maximum size of the coarse aggregate fraction were selected. Fiber reinforcement led to an increase in the strength of concrete at compression by 1,35 times and an increase in the tensile strength at bending by 3,4 times. At the second stage, the creep of fibrous concrete and plain concrete of similar composition at different stress levels was researched. Creep curves are plotted. It is shown that the use of fiber reinforcement leads to a decrease in creep strain by 21 to 30 percent, depending on the stress level.

  17. Pulmonary emphysema induced by methylphenidate: experimental study

    Gabriel Victor Guimarães Rapello

    Full Text Available CONTEXT AND OBJECTIVE: Methylphenidate is the most widely used drug for treating attention deficit hyperactivity disorder. However, it has important side effects, such as abdominal pain, insomnia, anorexia and loss of appetite, and also some cases of early severe emphysema after drug abuse have been reported. Our aim was to investigate the development of pulmonary emphysema in rats that were subjected to different doses of methylphenidate. DESIGN AND SETTING: Experimental study carried out at the laboratory of a public university. METHODS: Eighteen male Wistar rats were divided into three groups: control (0.9% saline solution; MP 0.8 (methylphenidate, 0.8 mg/kg; MP 1.2 (methylphenidate, 1.2 mg/kg. After 90 days of daily gavage, the animals were sacrificed and lung tissue samples were prepared for analysis on the mean alveolar diameter (Lm. RESULTS: The Lm was greater in MP 0.8 (47.91 ± 3.13; P < 0.01 and MP 1.2 (46.36 ± 4.39; P < 0.05 than in the control group (40.00 ± 3.48. CONCLUSION: Methylphenidate caused an increase in the alveolar diameter of rats, which was compatible with human pulmonary emphysema.

  18. Experimental study of trimethyl aluminum decomposition

    Zhang, Zhi; Pan, Yang; Yang, Jiuzhong; Jiang, Zhiming; Fang, Haisheng


    Trimethyl aluminum (TMA) is an important precursor used for metal-organic chemical vapor deposition (MOCVD) of most Al-containing structures, in particular of nitride structures. The reaction mechanism of TMA with ammonia is neither clear nor certain due to its complexity. Pyrolysis of trimethyl metal is the start of series of reactions, thus significantly affecting the growth. Experimental study of TMA pyrolysis, however, has not yet been conducted in detail. In this paper, a reflectron time-of-flight mass spectrometer is adopted to measure the TMA decomposition from room temperature to 800 °C in a special pyrolysis furnace, activated by soft X-ray from the synchrotron radiation. The results show that generation of methyl, ethane and monomethyl aluminum (MMA) indicates the start of the pyrolysis process. In the low temperature range from 25 °C to 700 °C, the main product is dimethyl aluminum (DMA) from decomposition of TMA. For temperatures larger than 700 °C, the main products are MMA, DMA, methyl and ethane.

  19. Learning, forecasting and optimizing : An experimental study

    Bao, Te; Duffy, John; Hommes, Cars

    Rational Expectations (RE) models have two crucial dimensions: (i) agents on average correctly forecast future prices given all available information, and (ii) given expectations, agents solve optimization problems and these solutions in turn determine actual price realizations. Experimental tests

  20. Learning, forecasting and optimizing: an experimental study

    Bao, T.; Duffy, J.; Hommes, C.


    Rational Expectations (RE) models have two crucial dimensions: (i) agents on average correctly forecast future prices given all available information, and (ii) given expectations, agents solve optimization problems and these solutions in turn determine actual price realizations. Experimental tests o

  1. Learning, forecasting and optimizing : An experimental study

    Bao, Te; Duffy, John; Hommes, Cars


    Rational Expectations (RE) models have two crucial dimensions: (i) agents on average correctly forecast future prices given all available information, and (ii) given expectations, agents solve optimization problems and these solutions in turn determine actual price realizations. Experimental tests o

  2. Learning, forecasting and optimizing: an experimental study

    Bao, T.; Duffy, J.; Hommes, C.


    Rational Expectations (RE) models have two crucial dimensions: 1) agents correctly forecast future prices given all available information, and 2) given expectations, agents solve optimization problems and these solutions in turn determine actual price realizations. Experimental testing of such model

  3. Evapotranspiration studies for protective barriers: Experimental plans

    Link, S.O.; Waugh, W.J.


    This document describes a general theory and experimental plans for predicting evapotranspiration in support of the Protective Barrier Program. Evapotranspiration is the combined loss of water from plants and soil surfaces to the atmosphere. 45 refs., 1 fig., 4 tabs.

  4. Experimental and modeling studies on the absorption of NO in aqueous ferrous EDTA solutions

    Gambardella, F; Alberts, MS; Winkelman, JGM; Heeres, EJ; Alberts, Michel S.; Heeres, H.J.


    This work describes an experimental and modeling study on an industrial relevant process (i.e., the absorption of NO in aqueous Fell(EDTA) solutions) to accurately determine the equilibrium constant of the reaction in the temperature range of 299-329 K. The experiments were carried out in a stirred

  5. Animal models of Parkinson's disease: limits and relevance to neuroprotection studies.

    Bezard, Erwan; Yue, Zhenyu; Kirik, Deniz; Spillantini, Maria Grazia


    Over the last two decades, significant strides has been made toward acquiring a better knowledge of both the etiology and pathogenesis of Parkinson's disease (PD). Experimental models are of paramount importance to obtain greater insights into the pathogenesis of the disease. Thus far, neurotoxin-based animal models have been the most popular tools employed to produce selective neuronal death in both in vitro and in vivo systems. These models have been commonly referred to as the pathogenic models. The current trend in modeling PD revolves around what can be called the disease gene-based models or etiologic models. The value of utilizing multiple models with a different mechanism of insult rests on the premise that dopamine-producing neurons die by stereotyped cascades that can be activated by a range of insults, from neurotoxins to downregulation and overexpression of disease-related genes. In this position article, we present the relevance of both pathogenic and etiologic models as well as the concept of clinically relevant designs that, we argue, should be utilized in the preclinical development phase of new neuroprotective therapies before embarking into clinical trials.

  6. Experimental and computational studies of nanofluids

    Vajjha, Ravikanth S.

    The goals of this dissertation were (i) to experimentally investigate the fluid dynamic and heat transfer performance of nanofluids in a circular tube, (ii) to study the influence of temperature and particle volumetric concentration of nanofluids on thermophysical properties, heat transfer and pumping power, (iii) to measure the rheological properties of various nanofluids and (iv) to investigate using a computational fluid dynamic (CFD) technique the performance of nanofluids in the flat tube of a radiator. Nanofluids are a new class of fluids prepared by dispersing nanoparticles with average sizes of less than 100 nm in traditional heat transfer fluids such as water, oil, ethylene glycol and propylene glycol. In cold regions of the world, the choice of base fluid for heat transfer applications is an ethylene glycol or propylene glycol mixed with water in different proportions. In the present research, a 60% ethylene glycol (EG) or propylene glycol (PG) and 40% water (W) by mass fluid mixture (60:40 EG/W or 60:40 PG/W) was used as a base fluid, which provides freeze protection to a very low level of temperature. Experiments were conducted to measure the convective heat transfer coefficient and pressure loss of nanofluids flowing in a circular tube in the fully developed turbulent regime. The experimental measurements were carried out for aluminum oxide (Al2O3), copper oxide (CuO) and silicon dioxide (SiO2) nanoparticles dispersed in 60:40 EG/W base fluid. Experiments revealed that the heat transfer coefficient of nanofluids showed an increase with the particle volumetric concentration. Pressure loss was also observed to increase with the nanoparticle volumetric concentration. New correlations for the Nusselt number and the friction factor were developed. The effects of temperature and particle volumetric concentration on different thermophysical properties (e.g. viscosity, thermal conductivity, specific heat and density) and subsequently on the Prandtl number

  7. Exploring the Relevance of Search Engines: An Overview of Google as a Case Study

    Ricardo Beltrán-Alfonso


    Full Text Available The huge amount of data on the Internet and the diverse list of strategies used to try to link this information with relevant searches through Linked Data have generated a revolution in data treatment and its representation. Nevertheless, the conventional search engines like Google are kept as strategies with good reception to do search processes. The following article presents a study of the development and evolution of search engines, more specifically, to analyze the relevance of findings based on the number of results displayed in paging systems with Google as a case study. Finally, it is intended to contribute to indexing criteria in search results, based on an approach to Semantic Web as a stage in the evolution of the Web.

  8. A 5 year prospective study of patient-relevant outcomes after total knee replacement

    Nilsdotter, A-K; Toksvig-Larsen, S; Roos, E M


    OBJECTIVE: To prospectively describe self-reported outcomes up to 5 years after total knee replacement (TKR) in Osteoarthritis (OA) and to study which patient-relevant factors may predict outcomes for pain and physical function (PF). METHODS: 102 consecutive patients with knee OA, 63 women and 39...... postoperatively. RESULTS: Response rate at 5 years was 86%. At 6 months significant improvement was seen in all KOOS and SF-36 scores (P

  9. Creativity and the homospatial process. Experimental studies.

    Rothenberg, A


    Through empirical studies involving intensive and extensive interviewing of outstanding creative persons in literature, visual art, and science, a specific creative cognitive operation involving complex mental imagery was identified. This operation has been designated the "homospatial process" and defined as actively conceiving two or more discrete entities occupying the same space, a conception leading to the articulation of new identities. Four experimental assessments involving exposure to stimuli designed to evoke the homospatial process have been carried out with groups of talented persons as follows: (1) 43 writers produced short poetic metaphors in response to 10 different pairs of slide stimuli. Subjects were randomly assigned to view the pairs either superimposed upon one another, and thereby appearing to occupy the same spatial location, or separated and side by side on the screen as a control condition. (2) 46 writers were similarly divided and exposed for a shortened period of time to the same stimuli in order to encourage mental elaboration in the creation of poetic metaphors. (3) Drawings were created by 43 artists separated into a group exposed to three superimposed images and a control group exposed to the same component images side by side. (4) 39 artists were separated into a group exposed to three superimposed images and a control group exposed to the same images constructed into a single-image figure-ground display. Findings were that, in all four experiments, subjects' productions in response to the superimposed visual stimuli were rated significantly higher in creativity, by independent experts, than productions in response to the control condition. Therefore, the externalized representations of the homospatial process facilitated both literary and artistic creativity.

  10. Experimental Study of Yishou Tiaozhi Tablet(

    ZHONG; Yi


    [1]XU SY. Screening method on lowering lipid drug and inhibiting arteriosclerosis drug. Pharmacological Experimental Methodology. Beijing: The People's Health Publishing House, 1985∶781-783.[2]LI YL. Assay of alkali hydrolytic decomposition method on serum HYP determination. Clinical Journal of Decimology 1988;6(2)∶69-71.[3]LI ZJ, HAN CS, WANG JX. Practical Radioimmunology. Beijing: The Scientific Technological Archive Publishing House, 1989∶198-221.[4]GAO YC. Effect of Yixing decoction on rats' serum lipid level in hyperlipidemia and its mechanism. Academic Journal of Traditional Chinese Medicine 1990;(5)∶53-56.[5]Manninen V, Tenkanen L. Lipid alteration and decline in the incidence of coronary heart disease in the Helsinki Heart Study. JAMA 1988;260∶641-651.[6]HUANG JG, translated. The atherosclerous lipid marker. Fascicle of Cardiovascular Disease in Journal of Foreign Medicine 1987;14(1)∶4-9.[7]YANG RX. Lp(a) and atherosclerosis. Journal of Progression on Cardiovascular Disease 1994;15(4)∶221-223.[8]Colin J, Schwartz MD. A modern view of atherogenesis. Am J Cardio 1993;71∶9B-14B.[9]LIN XQ. Exploration on relationship between HYP and atherosclerosis in hyperlipidemia. Journal of Chinese Circulation 1993;8(3)∶160-163.[10].CHEN SH. Hyperlipidemia and platelet high response. Fascicle of Cardiovascular Disease in Journal of Foreign Medicine 1989;16(5)∶257-262.

  11. Perceptions on Social Networking: A Study on Their Operational Relevance for the Navy


    In a 1967 sociometry study, researchers Jeffrey Travers and Stanley Milgram published An Experimental Study of the Small World Problem in which they...compromise U.S. security defenses. 1. Social Networks—Past and Present The sociometry research in the 1969 Travers and Milgram acquaintance chain

  12. Experimental Study of a Thermoelectric Generation System

    Zhu, Junpeng; Gao, Junling; Chen, Min


    A flat wall-like thermoelectric generation system is developed for applications in exhaust heat of kilns. The design of the whole experimental setup is presented. The essential performance of the thermoelectric generation system is tested, including open-circuit voltage, output power, and system....... System-level simulation is carried out using a quasi-one-dimensional numerical model that enables direct comparison with experimental results. The results of both experiment and simulation will provide a foundation to improve and optimize complex thermoelectric generation systems....

  13. Computatonal and experimental study of laminar flames

    Smooke, M.D.; Long, M.B. [Yale Univ., New Haven, CT (United States)


    This research has centered on an investigation of the effects of complex chemistry and detailed transport on the structure and extinction of hydrocarbon flames in counterflow, cylindrical and coflowing axisymmetric configurations. The authors have pursued both computational and experimental aspects of the research in parallel. The computational work has focused on the application of accurate and efficient numerical methods for the solution of the one and two-dimensional nonlinear boundary value problems describing the various reacting systems. Detailed experimental measurements were performed on axisymmetric coflow flames using two-dimensional imaging techniques. In particular, spontaneous Raman scattering and laser induced fluorescence were used to measure the temperature, major and minor species profiles.

  14. Biomass thermochemical gasification: Experimental studies and modeling

    Kumar, Ajay

    The overall goals of this research were to study the biomass thermochemical gasification using experimental and modeling techniques, and to evaluate the cost of industrial gas production and combined heat and power generation. This dissertation includes an extensive review of progresses in biomass thermochemical gasification. Product gases from biomass gasification can be converted to biopower, biofuels and chemicals. However, for its viable commercial applications, the study summarizes the technical challenges in the gasification and downstream processing of product gas. Corn stover and dried distillers grains with solubles (DDGS), a non-fermentable byproduct of ethanol production, were used as the biomass feedstocks. One of the objectives was to determine selected physical and chemical properties of corn stover related to thermochemical conversion. The parameters of the reaction kinetics for weight loss were obtained. The next objective was to investigate the effects of temperature, steam to biomass ratio and equivalence ratio on gas composition and efficiencies. DDGS gasification was performed on a lab-scale fluidized-bed gasifier with steam and air as fluidizing and oxidizing agents. Increasing the temperature resulted in increases in hydrogen and methane contents and efficiencies. A model was developed to simulate the performance of a lab-scale gasifier using Aspen Plus(TM) software. Mass balance, energy balance and minimization of Gibbs free energy were applied for the gasification to determine the product gas composition. The final objective was to optimize the process by maximizing the net energy efficiency, and to estimate the cost of industrial gas, and combined heat and power (CHP) at a biomass feedrate of 2000 kg/h. The selling price of gas was estimated to be 11.49/GJ for corn stover, and 13.08/GJ for DDGS. For CHP generation, the electrical and net efficiencies were 37 and 86%, respectively for corn stover, and 34 and 78%, respectively for DDGS. For

  15. Blast mitigation experimental and numerical studies


    Presents experimental methods of material and structural response to dynamic blast loads Includes computational analysis of material and structural response to dynamic blast loads Offers mitigation measures for structures in various environments Relates lab experiments to larger field tests Features more than 150 illustrations



    A series of Fe2O3-elimination experiments were conducted on feldspar samples from Tangshan Stone-powder Plant. These experimental methods include scrubbing desliming, flotation, rod milling and high gradient magnetic separation. Some technical factors of feldspar concentration and a new technological flow-sheet of ceramics raw material concentration were put forward.

  17. Study on Co-doped ZnO comparatively by first-principles calculations and relevant experiments

    Su, Y. L.; Zhang, Q. Y.; Zhou, N.; Ma, C. Y.; Liu, X. Z.; Zhao, J. J.


    Co-doped ZnO was studied using first-principles methods with comparison to experimental results taken from epitaxial Zn1-xCoxO (x 0.05) films. Density of Co2+ ions was determined using absorption spectra for the first time, and then a definite correlation between metallic Co clusters and the magnetism of the ZnCoO films was proved and the average number of Co atoms in the metallic Co clusters was estimated to be less than 200 using a superparamagnetic model. First-principles calculations of ZnCoO alloys and the relevant problems were discussed by comparing the electronic structures with absorption spectra and the results calculated by Tanabe-Sugano theory. U correction was proved to be necessary for calculating the band-gap energy of ZnCoO alloys, but other optical properties related to Co2+ ions are incorrect and the conclusion for magnetic properties is ambiguous due to uncertainty of the calculated highly localized states, which are in pressing for solution in study of material properties relevant to electronic structure.

  18. Model refinement for offshore platforms: Experimental study

    Zhang, Min; Chen, Zongli; Wu, Yanjian


    Offshore jacket platforms are widely used in offshore oil and gas exploitation. Finite element models of such structures need to have many degrees of freedom (DOFs) to represent the geometrical detail of complex structures, thereby leading to incompatibility in the number of DOFs of experimental models. To bring them both to the same order while ensuring that the essential eigen- properties of the refined model match those of experimental models, an extended model refinement procedure is presented in this paper. Vibration testing of an offshore jacket platform model is performed to validate the applicability of the proposed approach. A full-order finite element model of the platform is established and then tuned to meet the measured modal properties identified from the acceleration signals. Both model reduction and modal expansion methods are investigated, as well as various scenarios of sensor arrangements. Upon completion of the refinement, the updated jacket platform model matches the natural frequencies of the measured model well.

  19. Experimental studies of Steel Corrugated Constructions

    Lazarev Yuriy


    Full Text Available The purpose of this particular article is to assess existing calculations of steel corrugated constructions. Steel Corrugated Construction is a perspective type of constructions, which is exhibiting numerous advantages in comparison with one that currently applied in automobile and railroad networks (reinforced concrete water-throughput pipes, reinforced concrete frame bridges. The evaluation of experimental data on models of constructions of this particular type has been carried out in order to improve calculations of Steel Corrugated Constructions.

  20. Experimental Studies of the Fluvial System.


    drainage basins, alluvial fans, fan deltas, experiments, geomorphic, sedimentology , placers *w 20. ATRACr (Cktma -m reverse ab if neceeiv d IdentIfy by... sedimentology . A monograph has been prepared that SDD , 1473 Era’noNOF)MOV6SISOSOLETE UNCLASSIFIED SECURITY CLASSIFICATION OF THIS PAGE (lhen Data...LANDFORMS AND SEDIMENTOLOGY 9) ALLUVIAL FANS EXPEP1-1EWAL FtD I ES Experimental Procedure FLUVIAL FAN EXPERIMT TT Fluvial Fan Evolution Growth Patterns Growth


    Barannikov, V.; Nikolaeva, E; Kasatkina, S.


    This paper presents an experimental technique to investigate the dynamic behavior of copper under compression using the split Hopkinson pressure bar. We propose to measure thermophysical characteristics of copper specimens with the use of a classic adiabatic calorimeter. The measurements of heat energy, microand macrohardness and density of deformed specimens are made. The obtained results indicate that the evolution of the material structure plays a leading role in the dynamic process of pla...

  2. The effects of study-task relevance on perceptual repetition priming

    Holbrook, Jon B.; Bost, Preston R.; Cave, Carolyn Backer


    Repetition priming is easily elicited in many traditional paradigms, and the possibility that perceptual priming may be other than an automatic consequence of perception has received little consideration. This issue is explored in two experiments. In Experiment 1, participants named the target from a four-item category search study task more quickly than the nontarget study items at a later naming test. Experiment 2 extended this finding to conditions in which stimuli were individually presented at study. In three different study tasks, stimuli relevant to study-task completion elicited priming on a later test, but stimuli presented outside the context of a task did not. In both experiments, recognition was above chance for nonrelevant stimuli, suggesting that participants explicitly remembered stimuli that did not elicit priming. Results suggest that priming is sensitive to study-task demands and may reflect a more adaptive and flexible mechanism for modification of perceptual processing than previously appreciated.

  3. Developing optimal search strategies for retrieving clinically relevant qualitative studies in EMBASE.

    Walters, Leslie A; Wilczynski, Nancy L; Haynes, R Brian


    Qualitative researchers address many issues relevant to patient health care. Their studies appear in an array of journals, making literature searching difficult. Large databases such as EMBASE provide a means of retrieving qualitative research, but these studies represent only a minuscule fraction of published articles, making electronic retrieval problematic. Little work has been done on developing search strategies for the detection of qualitative studies. The objective of this study was to develop optimal search strategies to retrieve qualitative studies in EMBASE for the 2000 publishing year. The authors conducted an analytic survey, comparing hand searches of journals with retrievals from EMBASE for candidate search terms and combinations. Search strategies reached peak sensitivities at 94.2% and peak specificities of 99.7%. Combining search terms to optimize the combination of sensitivity and specificity resulted in values over 89% for both. The authors identified search strategies with high performance for retrieving qualitative studies in EMBASE.

  4. Epidemiological and histopathological study of relevance of Guizhou Maotai liquor and liver diseases

    Jun Wu; Yu-Mei Yao; Ying-Ying Zhang; Lan-Zhen Ren; Lan Ye; Ling Li; Hui-Na Zhang; Ming-Liang Cheng; Guo-Hao Zhang; Rong-Wei Zhai; Neng-Hui Huang; Cheng-Xiu Li; Tian-Yong Luo; Shuang Lu; Zhi-Qin Yu


    AIM: To explore the relevance of Maotai liquor and liverdiseases.METHODS: Epidemiological study was conducted on groupsof subjects, each consisting of 3 subjects from the Maotailiquor group consisting of 99 individuals and one from thenon-alcoholic control group consisting of 33 individuals.Liver biopsy was performed on 23 volunteers from GuizhouMaotai Distillery who had a constant and long history ofdrinking Maotai liquor. Experimental histopathological studywas conducted as follows: sixty male Wistar rats weredivided into 3 groups randomly and fed with Maotai liquor,ordinary white wine, and physiological saline respectivelyfor a period of 8 and 12 weeks The rats were sacrificed inbatches, then serum ALT,AST, TBil, and AKP weremeasured. Rat livers were harvested to measure the liverindexes, GSH, and MDA. Histopathological examinationswere also performod. Another eighty mica were randomlydivided into 4 groups and fed with Maotei (at differentdosages of 10 mi @ kg-1 and 20 mi @ kg-1 ), ethanol, andphysiological saline. The animals were sacrificed after 4weeks and serum ALT was determined. Then the livers wereharvested and liver indexes and MDA were measured.RESULTS: The incidence rate of hepatic symptoms,splenomegaly, liver function imlairment, reversal ofAIbumin/Glolulin and increased diameter of portal veins inthe Maotai liquor group were 1.0 %(1/99), 1.0 %(1/99), 1.0% (1/99), 1.0 % (1/99), 0(0/99)and 0(0/99), 0(0/99) ,0(0/99),0(0/99), 0 (0/99), respectively. There was no significantdifference between the Maotai group and the non-alcoholiccontrol group( P > 0.05). Various degree of fatty infiltrationof hepatocytes was found in the 23 volunteers receiving liverbiopsy, uut there was no obvious hepatic fibrosis orcirrhosis. A compsrison was made between the Maotailiquor group and the ordinary white wine group. It wasfound that hepatic MDA in rats and mice were 0.33 + 0.10and 0.49 + 0.23 respectively in Maotai group and 0.61 + 0.22and0.66+0.32 in the ordinary white

  5. Electron microscopic study of experimental thallotoxicosis.

    Deshimaru, M; Miyakawa, T; Sumiyoshi, S; Yasuoka, F; Kawano, K


    To adult male rats 2 mg per rat of thallium acetate: CH3 COOT1 was given orally daily for six months. Clinically, the experimental rats revealed only alopecia and showed no neurological signs. Pathological findings were noted in muscle and cerebrum. Marked changes were observed in muscles and were as follows: swelling and vacuolation of mitochondria, destruction of cristae, ruptures of mitochondrial membranes, degeneration of sarcoplasmic reticulum and destruction of myofilaments. In the cerebrum, there were vacuolation of mitochondria, dilatation of Golgi cisterns in hypothalamus and thalamus. Sciatic nerve, liver and kidney were intact. From this, we consider that T1+ ions selectively affect the muscle and its mitochondria.

  6. Ovine and Caprine Toxoplasmosis: Experimental Study


    Eighteen mature ewes of the Mytilene breed and 18 mature Local- Damascus crossbred goats, seronegative for Toxoplasma gondii (T. gondii) by ELISA were used. All animals were mated after synchronization of estrus. On day 90 of pregnancy, animals were randomly assigned to 3 experimental groups; 6 ewes (S1) and 6 goats (G1) were orally inoculated by stomach tube with 1000 oocysts; 6 ewes (S2) and 6 goats (G2) were orally inoculated with a non-infected control inoculum. On day 140+2 of pregnancy,...

  7. Experimental study of the nucleon spin structure

    Litmaath, M.F.


    After introducing the theoretical framework, which includes DIS, the Quark Parton Model (QPM) and QCD, we describe the implementation of the experiment. The SMC uses a beam of 190 GeV naturally polarized muons, scattering off nucleons in a large cryogenic target containing protons or deuterons that are polarized through Dynamic Nuclear Polarization (DNP). The target material is located in two cells in a row, with opposite polarizations. Every 5 hours the polarizations of both cells are reversed. The target polarization is measured by an NMR system. The polarization of the beam is measured in a polarimeter, located downstream of the main experimental setup. (orig.).

  8. Experimental and Numerical Study of Damaged Cantilever

    Rytter, A.; Krawczuk, M.; Kirkegaard, Poul Henning


    The introduction of a crack in a steel structure will cause a local change in the stiffness and damping capacity. The change in stiffness will lead to a change of some of the natural frequencies of the structure and a discontinuity in the associated mode shapes. This paper contains a presentation...... of the results from experimental and numerical tests with hollow section cantileves containing fatigue cracks. Two different finite-element (FE) models have been used to estimate the modal parameters numerically. The first FE model consists of beam elements. The second FE model consists of traditional...

  9. The relevance of a rules-based maize marketing policy: An experimental case study of Zambia

    Abbink, K.; Jayne, T.S.; Moller, L.C.


    Strategic interaction between public and private actors is increasingly recognized as an important determinant of agricultural market performance in Africa and elsewhere. Trust and consultation tend to positively affect private activity while uncertainty of government behavior impedes it. This paper

  10. Feasibility study of the AOSTA experimental campaign

    Carta M.


    Full Text Available The reduction of the nuclear waste is one of the most important nuclear issues. The high radiotoxicity of the spent fuel is due to plutonium and some minor actinides (MAs such as neptunium, americium and curium, above all. One way to reduce their hazard is to destroy by fission MAs in appropriate nuclear reactors. To allow the MAs destruction an important effort have been done on the nuclear data due to the poor knowledge in this field. In the framework of one of the NEA Expert Group on Integral Experiments for Minor Actinide Management an analysis of the feasibility of MAs irradiation campaign in the TAPIRO fast research reactor is carried out. This paper provides preliminary results obtained by calculations modelling the irradiation, in different TAPIRO irradiation channels, of some CEA samples coming from the French experimental campaign OSMOSE, loaded with different contents of MAs, in order to access, through particular peak spectrometry, to their capture cross section. On the basis of neutron transport calculation results, obtained by both deterministic and Monte Carlo methods, an estimate of the irradiated samples counting levels from the AOSTA (Activation of OSMOSE Samples in TAPIRO experimental campaign is provided.

  11. A Experimental Study of Viscous Vortex Rings.

    Dziedzic, Mauricio

    Motivated by the role played by vortex rings in the process of turbulent mixing, the work is focused on the problem of stability and viscous decay of a single vortex ring. A new classification is proposed for vortex rings which is based on extensive hot-wire measurements of velocity in the ring core and wake and flow visualization. Vortex rings can be classified as laminar, wavy, turbulence-producing, and turbulent. Prediction of vortex ring type is shown to be possible based on the vortex ring Reynolds number. Linear growth rates of ring diameter with time are observed for all types of vortex rings, with different growth rates occurring for laminar and turbulent vortex rings. Data on the viscous decay of vortex rings are used to provide experimental confirmation of the accuracy of Saffman's equation for the velocity of propagation of a vortex ring. Experimental data indicate that instability of the vortex ring strongly depends on the mode of generation and can be delayed by properly adjusting the generation parameters. A systematic review of the literature on vortex-ring interactions is presented in the form of an appendix, which helps identify areas in which further research may be fruitful.

  12. [Experimental studies of sonography of the meniscus].

    Casser, H R; Füsting, M; Tenbrock, F


    The aim of this examination was to recognize and, if possible, avoid the origin of artifact images in sonograms caused anatomically and by the physics of ultrasound. Experimental investigations were carried out in a waterbath on models of knee joints using Schlierenoptics and on specimens from corpse knees. When a sector transducer was used, the artifact images that originated in the joint cavity appeared outside the cavity on the sonogram so that there were no danger of mistaking them for reflected images of tears in lesions of the meniscus. In sonography, the surfaces of tears reflect a strong signal, but diagnosis depends on the position of the edges of the tears to the direction of the ultrasonic waves, which means to get a reliable record of tears of the meniscus is only possible by means of a dynamic examination technique.

  13. Experimental Study of Pollutant Transfer within Dwellings

    Koffi, Juslin; Allard, Francis; Husaunndee, Ahmad


    A mechanical ventilation principle used in French residential buildings was tested in the experimental house of the CSTB research centre. The experiments dealt with pollutant removal efficiency of this ventilation principle, mainly with air tightness and the influence of internal doors. Tracer gas constant injection method was used to simulate the pollution source in the living room. SF6 concentrations were measured in several rooms. The results showed that the air flow routes were in agreement with the theory as long as internal doors were closed. When doors were open, the air pattern was disturbed a lot; a great quantity of the emitted pollutant was measured in the bedrooms. Besides, stack effect promotes the pollutant moving towards the bedrooms under higher indoor-outdoor air temperature differences. In addition, the results showed that if the opening of the bedroom window increases the air change rate, it does not guarantee a good indoor air quality.

  14. Experimental study of external fuel vaporization

    Szetela, E. J.; Tevelde, J. A.


    The fuel properties used in the design of a flash vaporization system for aircraft gas turbine engines were evaluated in experiments using a flowing system to determine critical temperature and pressure, boiling points, dew points, heat transfer coefficients, deposit formation rates, and deposit removal. Three fuels were included in the experiments: Jet-A, an experimental referree broad specification fuel, and a premium No. 2 diesel fuel. Engine conditions representing a NASA Energy Efficient Engine at sea-level take-off, cruise, and idle were simulated in the vaporization system and it was found that single phase flow was maintained in the heat exchanger and downstream of the throttle. Deposits encountered in the heat exchanger represented a thermal resistance as high as 1300 sq M K/watt and a deposit formation rate over 1000 gC/sq cm hr.

  15. Theoretical and experimental studies of elementary physics

    Bodek, A.; Ferbel, T.; Melissinos, A.C.; Olsen, S.; Slattery, P.; Tipton, P.; Das, A.; Hagen, C.R.; Rajeev, S.G.; Okubo, S.


    The experimental high energy physics program is directed toward the execution of experiments that probe the basic constituents of matter and the forces between them. These experiments are carried out at national and international accelerator facilities. At the current time, we are primarily concentrating on the following projects: Direct photon production in hadronic reactions (Fermilab E706); Production of hybrid mesons in the nuclear Coulomb field; The D-Zero experiment at the Tevatron collider; Deep inelastic neutrino- and electron-nucleon scattering at FNAL and SLAC; Nonlinear QED at critical field strengths at SLAC; The Experiments at KEK (AMY, 17keV neutrino); The CDF experiment at the Tevatron collider; and SSC-related detector R D on scintillating tile- and diamond-based calorimetry and microstrip tracking detectors.

  16. Experimental study of collisional granular flows down an inclined plane

    Azanza, Emmanuel; Chevoir, François; Moucheront, Pascal


    The collisional flow of a slightly inelastic granular material down a rough inclined plane is usually described by kinetic theories. We present an experimental study aimed at analysing the assumptions and the quantitative predictions of such theories. A two-dimensional channel coupled to a model granular material and image analysis allow detailed and complete measurement of the kinematics and structure of the flows. We determine the range of inclination and particle flux for which the flow is stationary and uniform. The characteristic profiles of solid fraction, mean velocity and granular temperature are systematically measured. Both the true collisional and the dilute kinetic regimes are examined. We show that a quasi-hydrodynamic description of these regimes seems relevant, and that the pressure and the viscosity terms are in good qualitative agreement with the prediction of the kinetic theory. The profiles are well described by the kinetic theory near the top of the flow, at low solid fraction. Conversely there are large discrepancies near the rough plane, where the material is structured in layers.

  17. Computational and experimental study of laminar flames

    Smooke, Mitchell [Yale Univ., New Haven, CT (United States)


    During the past three years, our research has centered on an investigation of the effects of complex chemistry and detailed transport on the structure and extinction of hydrocarbon flames in coflowing axisymmetric configurations. We have pursued both computational and experimental aspects of the research in parallel on both steady-state and time-dependent systems. The computational work has focused on the application of accurate and efficient numerical methods for the solution of the steady-state and time-dependent boundary value problems describing the various reacting systems. Detailed experimental measurements were performed on axisymmetric coflow flames using two-dimensional imaging techniques. Previously, spontaneous Raman scattering, chemiluminescence, and laser-induced fluorescence were used to measure the temperature, major and minor species profiles. Particle image velocimetry (PIV) has been used to investigate velocity distributions and for calibration of time-varying flames. Laser-induced incandescence (LII) with an extinction calibration was used to determine soot volume fractions, while soot surface temperatures were measured with three-color optical pyrometry using a color digital camera. A blackbody calibration of the camera allows for determination of soot volume fraction as well, which can be compared with the LII measurements. More recently, we have concentrated on a detailed characterization of soot using a variety of techniques including time-resolved LII (TiRe-LII) for soot primary particles sizes, multi-angle light scattering (MALS) for soot radius of gyration, and spectrally-resolved line of sight attenuation (spec-LOSA). Combining the information from all of these soot measurements can be used to determine the soot optical properties, which are observed to vary significantly depending on spatial location and fuel dilution. Our goal has been to obtain a more fundamental understanding of the important fluid dynamic and chemical interactions in

  18. A Simple, Inexpensive, and Field-Relevant Microcosm Tidal Simulator for Use in Marsh Macrophyte Studies

    Rachel M. MacTavish


    Full Text Available Premise of the study: A microcosm unit with tidal simulation was developed to address the challenge of maintaining ecologically relevant tidal regimes while performing controlled greenhouse experiments on smooth cordgrass, Spartina alterniflora. Methods and Results: We designed a simple, inexpensive, easily replicated microcosm unit with tidal simulation and tested whether S. alterniflora growth in microcosms with tidal simulation was similar to that of tidally influenced plants in the field on Sapelo Island, Georgia. After three months of exposure to either natural or simulated tidal treatment, plants in microcosms receiving tidal simulation had similar stem density, height, and above- and belowground biomass to plants in field plots. Conclusions: The tidal simulator developed may provide an inexpensive, effective method for conducting studies on S. alterniflora and other tidally influenced plants in controlled settings to be used not only to complement field studies, but also in locations without coastal access.

  19. Lab-on-a-brane: A novel physiologically relevant planar arterial model to study transendothelial transport

    Budhwani, Karim Ismail

    The tremendous quality of life impact notwithstanding, cardiovascular diseases and Cancer add up to over US$ 700bn each year in financial costs alone. Aging and population growth are expected to further expand the problem space while drug research and development remain expensive. However, preclinical costs can be substantially mitigated by substituting animal models with in vitro devices that accurately model human cardiovascular transport. Here we present a novel physiologically relevant lab-on-a-brane that simulates in vivo pressure, flow, strain, and shear waveforms associated with normal and pathological conditions in large and small blood vessels for studying molecular transport across the endothelial monolayer. The device builds upon previously demonstrated integrated microfluidic loop design by: (a) introducing nanoscale pores in the substrate membrane to enable transmembrane molecular transport, (b) transforming the substrate membrane into a nanofibrous matrix for 3D smooth muscle cell (SMC) tissue culture, (c) integrating electrospinning fabrication methods, (d) engineering an invertible sandwich cell culture device architecture, and (e) devising a healthy co-culture mechanism for human arterial endothelial cell (HAEC) monolayer and multiple layers of human smooth muscle cells (HSMC) to accurately mimic arterial anatomy. Structural and mechanical characterization was conducted using confocal microscopy, SEM, stress/strain analysis, and infrared spectroscopy. Transport was characterized using FITC-Dextran hydraulic permeability protocol. Structure and transport characterization successfully demonstrate device viability as a physiologically relevant arterial mimic for testing transendothelial transport. Thus, our lab-on-a-brane provides a highly effective and efficient, yet considerably inexpensive, physiologically relevant alternative for pharmacokinetic evaluation; possibly reducing animals used in pre-clinical testing, clinical trials cost from false

  20. Minimally invasive swine experimental model for the in vivo study of liver metabolism of drugs

    Piazza, Ornella; Romano, Rosalba; Scarpati, Giuliana; Esposito, Ciro; Cavaglià, Enrico; Corona, Marco


    Purpose: To develop a clinically relevant porcine model for the study of hepatic metabolism of drugs by means of hepatic vein catheterization. Materials and Methods: review of literature and elaboration of a hypothesis, design of an experimental method. Results: recent clinical studies were conducted by withdrawing cirrhotic patients’ blood from right hepatic vein during hepatic vein pressure gradient measurements. Basing on our personal clinical experience a...

  1. Electron microscopy of human peripheral nerves of clinical relevance to the practice of nerve blocks. A structural and ultrastructural review based on original experimental and laboratory data.

    Reina, M A; Arriazu, R; Collier, C B; Sala-Blanch, X; Izquierdo, L; de Andrés, J


    The goal is to describe the ultrastructure of normal human peripheral nerves, and to highlight key aspects that are relevant to the practice of peripheral nerve block anaesthesia. Using samples of sciatic nerve obtained from patients, and dural sac, nerve root cuff and brachial plexus dissected from fresh human cadavers, an analysis of the structure of peripheral nerve axons and distribution of fascicles and topographic composition of the layers that cover the nerve is presented. Myelinated and unmyelinated axons, fascicles, epineurium, perineurium and endoneurium obtained from patients and fresh cadavers were studied by light microscopy using immunohistochemical techniques, and transmission and scanning electron microscopy. Structure of perineurium and intrafascicular capillaries, and its implications in blood-nerve barrier were revised. Each of the anatomical elements is analyzed individually with regard to its relevance to clinical practice to regional anaesthesia. Routine practice of regional anaesthetic techniques and ultrasound identification of nerve structures has led to conceptions, which repercussions may be relevant in future applications of these techniques. In this regard, the ultrastructural and histological perspective accomplished through findings of this study aims at enlightening arising questions within the field of regional anaesthesia. Copyright © 2013 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Published by Elsevier España. All rights reserved.

  2. An experimental study of human birth models

    Baumer, Alexa; Gossmann, Roseanna; Fauci, Lisa J.; Leftwich, Megan C.


    The laboring uterus is a complex and dynamic fluid system. Relatively little is known about the fluid properties in this system. However, the two primary fluids of interest, amniotic fluid and vernix caseosa, likely play integral roles in the force transferred to the fetus during the final stages of parturition. This investigation probes the role of fluid in the force transfer during delivery by considering physical models that determine the role of various components of the full system. The first experimental model represents the fetus passing through the birth canal as concentric cylinders with a fluid filled gap. The rigid, inner cylinder moves through the highly flexible outer cylinder at a prescribed velocity. The geometry of the inner cylinder is varied by aspect ratio and length. A total of five different inner geometries are used to fully investigate the parameter space. As the inner cylinder moves through the outer cylinder, strain measurements are taken. These measurements are converted to force measurements as a function of time and position in the outer cylinder. The results of these experiments are compared with numerical results to form a more complete picture of force transfer. This model can be used as the foundation for predicting the force needed to deliver a fetus in the final stages of parturition. Additionally, more complex models, that incorporate uterine contraction forces, are being developed.

  3. Economic principles in communication: an experimental study.

    De Jaegher, Kris; Rosenkranz, Stephanie; Weitzel, Utz


    This paper experimentally investigates how economic principles affect communication. In a simple sender-receiver game with common interests over payoffs, the sender can send a signal without a pre-given meaning in an infrequent or frequent state of the world. When the signal is costly, several theories (focal point theory, the intuitive criterion, evolutionary game theory) predict an efficient separating equilibrium, where the signal is sent in the infrequent state of the world (also referred to as Horn׳s rule). To analyze whether Horn׳s rule applies, and if so, which theory best explains it, we develop and test variants of the sender-receiver game where the theories generate discriminatory hypotheses. In costly signaling variants, our participants follow Horn׳s rule most of the time, in a manner that is best explained by focal point theory. In costless signaling variants, evolutionary game theory best explains our results. Here participants coordinate significantly more (less) often on a separating equilibrium where the signal is sent in the frequent state if they are primed to associate the absence of a signal with the infrequent (frequent) state of the world. We also find indications that a similar priming effect applies to costly signals. Thus, while the frequency with which participants follow Horn׳s rule in costly signaling variants is best explained by Horn׳s rule, the priming effect shows that some of our participants׳ behavior is best explained by evolutionary game theory even when signals are costly.

  4. Experimental studies of a drumlike silencer.

    Choy, Y S; Huang, Lixi


    The theoretical finding of the broadband performance of a reactive silencer is validated experimentally. The silencer consists of two highly stretched membranes lining part of the duct and backed by two long and shallow cavities. The test rig was built with a small square duct of 5 cm in dimension, and each cavity is 5 cm deep and 25 cm long. Two types of metal foils, stainless steel and copper, were used, and the lowest membrane-to-air mass ratio was 1.3. A transmission loss in excess of 10 dB was achieved over more than one octave band. For one configuration close to the optimal parameters, the predicted ratio of the frequency band limits is 2.47, while the experiment gave 2.35. Three spectral peaks were found in the stopband, as predicted, but the peaks were broader than prediction, indicating the presence of significant sound energy dissipation mechanisms. Comparison with theoretical simulation shows that the cavity damping dominates over membrane friction. Tests using heavier membranes and membrane with different levels of tension also agree with predictions. Issues of practical implementation of the concept as a flow-through silencer are also addressed.

  5. Experimental study on HVAC sound parameters

    Bujoreanu, C.; Benchea, M.


    HVAC system represent major source of buildings internal noise and therefore they are designed to provide a human acoustic comfort besides the thermal and air quality requirements. The paper experimentally investigates three types of commercial air handler units (AHU) with different ducts cross-section sizes and inlet-outlet configuration. The measurements are performed in an anechoic room. The measurements are carried out at different fan's speeds, ranging the power-charge from 30-100% while the duct air flow is slowly adjusted from full open to full closed, between 0-500 Pa. The sound pressure levels of the radiant units are rated using NR curves. Also, the supply and the outdoor ducts sound levels are compared in order to point the frequencies where the noise must be reduced. Third-octave band analysis of random noise of an air handling unit from a HVAC system is realized, using measurement procedures that agrees the requirements of the ISO 3744:2011 and ISO 5136:2010 standards. The comparatively results highlight the effects of the geometry, air flow pressure and power-charging dependencies upon the sound level. This is the start for a noise reduction strategy.

  6. Using music to study the evolution of cognitive mechanisms relevant to language.

    Patel, Aniruddh D


    This article argues that music can be used in cross-species research to study the evolution of cognitive mechanisms relevant to spoken language. This is because music and language share certain cognitive processing mechanisms and because music offers specific advantages for cross-species research. Music has relatively simple building blocks (tones without semantic properties), yet these building blocks are combined into rich hierarchical structures that engage complex cognitive processing. I illustrate this point with regard to the processing of musical harmonic structure. Because the processing of musical harmonic structure has been shown to interact with linguistic syntactic processing in humans, it is of interest to know if other species can acquire implicit knowledge of harmonic structure through extended exposure to music during development (vs. through explicit training). I suggest that domestic dogs would be a good species to study in addressing this question.

  7. A Numerical/Experimental Study of Nitinol Actuator Springs

    Auricchio, Ferdinando; Scalet, Giulia; Urbano, Marco


    This study deals with the numerical modeling, simulation and experimental analysis of shape-memory alloy (SMA) helicoidal springs. An experimental campaign is conducted on both SMA straight wires and helicoidal springs that experienced the same annealing process. Then, we use such experimental results to investigate three phenomenological constitutive models able to represent SMA macroscopic behavior. In particular, after the identification of all the material parameters from experimental results on SMA wires, we inspect the thermo-mechanical behavior of SMA helicoidal springs by comparing numerical predictions to experimental data. Finally, we discuss models capabilities and some aspects characterizing SMA material behavior.

  8. Thinking outside the (Voice) Box: A Case Study of Students' Perceptions of the Relevance of Anatomy to Speech Pathology

    Weir, Kristy A.


    Speech pathology students readily identify the importance of a sound understanding of anatomical structures central to their intended profession. In contrast, they often do not recognize the relevance of a broader understanding of structure and function. This study aimed to explore students' perceptions of the relevance of anatomy to speech…

  9. Study Gaps Relevant to Use of Complementary Medicine in Patients With Leukemia: A Review Study



    Full Text Available Context A review of the literature of recent decades has shown that few studies have been conducted on the effects of various types of complementary medicine on patients with leukemia. Therefore, the present study aimed to find research gaps in the use of different types of complementary medicine in patients with leukemia to be applied in future studies. Evidence Acquisition The present study was a review-type design based on a review of the literature on different types of complementary medicine in patients with leukemia, up to 2015. The search was conducted through electronic databases and search engines. According to the inclusion and exclusion criteria, 8 studies which had been conducted on the use of complementary medicine in patients with leukemia were selected for the identification of gaps. Results The overall results showed that few studies have been conducted on the use of exercise, massage therapy, music therapy, acupressure, and healing touch in patients with leukemia, and these subjects are potential research areas for many different studies. However, no studies have been carried out on the effects of acupuncture, relaxation, and yoga on these patients. Conclusions The results of this review showed that the number of studies on the use of complementary medicine in leukemia patients is very limited (especially in Iran, and it can be the subject of numerous studies in the future.

  10. Theoretical & Experimental Studies of Elementary Particles

    McFarland, Kevin


    Abstract High energy physics has been one of the signature research programs at the University of Rochester for over 60 years. The group has made leading contributions to experimental discoveries at accelerators and in cosmic rays and has played major roles in developing the theoretical framework that gives us our ``standard model'' of fundamental interactions today. This award from the Department of Energy funded a major portion of that research for more than 20 years. During this time, highlights of the supported work included the discovery of the top quark at the Fermilab Tevatron, the completion of a broad program of physics measurements that verified the electroweak unified theory, the measurement of three generations of neutrino flavor oscillations, and the first observation of a ``Higgs like'' boson at the Large Hadron Collider. The work has resulted in more than 2000 publications over the period of the grant. The principal investigators supported on this grant have been recognized as leaders in the field of elementary particle physics by their peers through numerous awards and leadership positions. Most notable among them is the APS W.K.H. Panofsky Prize awarded to Arie Bodek in 2004, the J.J. Sakurai Prizes awarded to Susumu Okubo and C. Richard Hagen in 2005 and 2010, respectively, the Wigner medal awarded to Susumu Okubo in 2006, and five principal investigators (Das, Demina, McFarland, Orr, Tipton) who received Department of Energy Outstanding Junior Investigator awards during the period of this grant. The University of Rochester Department of Physics and Astronomy, which houses the research group, provides primary salary support for the faculty and has waived most tuition costs for graduate students during the period of this grant. The group also benefits significantly from technical support and infrastructure available at the University which supports the work. The research work of the group has provided educational opportunities

  11. Study on C-E Translation of Advertisements Based on Relevance Theory



    The main errors in translating Chinese advertisements into English are pragmatic failures in which target-language readers fail to find the optimal relevance between the target text and source text.The translation strategies proposed under the guidance of Relevance Theory can effectively help translators find out optimal relevance in the process of translating Chinese ad-vertisements into English to avoid pragmatic failures .

  12. Experimental studies on urea degradation in seawater

    Rajendran, A.; Joseph, T.; Reddy, C.V.G.

    The rate of urea degradation in seawater was studied under various conditions and the kinetics of urea degradation was evaluated. Urea decomposition experiments showed that the rates and quantity of ammonium oxidation were slower in the relatively...

  13. A Tentative Study on the Relevance of Progressivism to ELT:Perspective of Learner-centredness



    For the sake of its inseparability to the science of language, English language teaching (ELT) tends to be researched, despite diverse voices within its domain, from the perspective of linguistics. It is noticeable, however, that ELT in this research conducted is literally referred to as an educational conception, though pertinent linguistics knowledge is to be inevitably in-volved. Given this situation, ELT is categorised as an intra-discipline of education, establishing the basic ground of the academic enquiries throughout the context. Relevant issues are to be further examined concerning to what extent learner-centredness mani-fests its definition within modern pedagogical approaches and methods of ELT, so as to indicate the philosophical significance of education in language teaching. A critical insight is to be given into the limitations of learner-centredness in ELT practice through two case studies thereafter, which is expected to benefit the development of ELT professionalism in the changing prac-tice of language education.

  14. Breast cancer education for Navajo women: a pilot study evaluating a culturally relevant video.

    Sanderson, Priscilla R; Teufel-Shone, Nicolette I; Baldwin, Julie A; Sandoval, Nellie; Robinson, Frances


    This pilot study evaluated a culturally specific video designed to teach Navajo women about breast cancer treatment options. Fourteen Navajo women diagnosed with breast cancer and 26 healthcare providers participated in a mixed-method evaluation that documented their perceptions immediately and 6 months after viewing the video. After initial viewing, women reported reduced anxiety about treatment and interest in support groups. Six months later, women said the video prompted them to seek more information from printed sources and their provider. Younger Navajo women who were 44 to 51 years old were more likely to attend support groups than women who were 55-67 years. Providers corroborated the positive effects of the video. The providers believed the video encouraged patients to seek information about breast cancer and to ask questions about treatment plans and side effects. A culturally relevant video for Navajo women can be an effective teaching tool and can enhance patient-provider communication.

  15. Turbulence study in the vicinity of piano key weir: relevance, instrumentation, parameters and methods

    Tiwari, Harinarayan; Sharma, Nayan


    This research paper focuses on the need of turbulence, instruments reliable to capture turbulence, different turbulence parameters and some advance methodology which can decompose various turbulence structures at different levels near hydraulic structures. Small-scale turbulence research has valid prospects in open channel flow. The relevance of the study is amplified as we introduce any hydraulic structure in the channel which disturbs the natural flow and creates discontinuity. To recover this discontinuity, the piano key weir (PKW) might be used with sloped keys. Constraints of empirical results in the vicinity of PKW necessitate extensive laboratory experiments with fair and reliable instrumentation techniques. Acoustic Doppler velocimeter was established to be best suited within range of some limitations using principal component analysis. Wavelet analysis is proposed to decompose the underlying turbulence structure in a better way.

  16. Turbulence study in the vicinity of piano key weir: relevance, instrumentation, parameters and methods

    Tiwari, Harinarayan; Sharma, Nayan


    This research paper focuses on the need of turbulence, instruments reliable to capture turbulence, different turbulence parameters and some advance methodology which can decompose various turbulence structures at different levels near hydraulic structures. Small-scale turbulence research has valid prospects in open channel flow. The relevance of the study is amplified as we introduce any hydraulic structure in the channel which disturbs the natural flow and creates discontinuity. To recover this discontinuity, the piano key weir (PKW) might be used with sloped keys. Constraints of empirical results in the vicinity of PKW necessitate extensive laboratory experiments with fair and reliable instrumentation techniques. Acoustic Doppler velocimeter was established to be best suited within range of some limitations using principal component analysis. Wavelet analysis is proposed to decompose the underlying turbulence structure in a better way.

  17. Laboratory Studies of Chemical and Photochemical Processes Relevant to Stratospheric Ozone

    Villalta, Peter W.; Zahniser, Mark S.; Nelson, David D.; Kolb, Charles E.


    The purpose of this project is to reduce the uncertainty in several key gas-phase kinetic processes which impact our understanding of stratospheric ozone. The main emphasis of this work is on measuring rate coefficients and product channels for reactions of HO(x) and NO(x) species in the temperature range 200 K to 240 K relevant to the lower stratosphere. The results of these studies will improve models of stratospheric ozone chemistry and predictions of perturbations due to human influences. The second year's effort has focussed the design and construction of the proposed high pressure flow reactor on three separate areas: (1) the construction of the high pressure flow reactor; (2) characterization of the turbulent flow profile; and (3) demonstration of the instrument by measuring HO2 + NO2 and HO2 + NO reaction rate coefficients.

  18. Clinical relevance of cluster analysis in phenotyping allergic rhinitis in a real-life study.

    Bousquet, Philippe Jean; Devillier, Philippe; Tadmouri, Abir; Mesbah, Kamal; Demoly, Pascal; Bousquet, Jean


    Disease stratification, using phenotypic characterization performed either by hypothesis- or data-driven methods, was developed to improve clinical decisions. However, cluster analysis has not been used for allergic rhinitis. To define clusters in allergic rhinitis and to compare them with ARIA (Allergic Rhinitis and Its Impact on Asthma), a hypothesis-driven approach. A French observational prospective multicenter study (EVEIL: Echelle visuelle analogique dans la rhinite allergique) was carried out on 990 patients consulting general practitioners for allergic rhinitis and treated as per clinical practice. In this study, changes in symptom scores, visual analogue scales and quality of life were measured at baseline and after 14 days of treatment. A post hoc analysis was performed to identify clusters of patients with allergic rhinitis – using Ward's hierarchical method – and to define their clinical relevance at baseline and after 14 days of treatment. The cluster approach was compared to the ARIA approach. Patients were clustered into 4 phenotypes which partly followed the ARIA classes. These phenotypes differed in their disease severity including symptoms and quality of life. Physicians in real-life practice prescribed medication regardless of the phenotype and severity, with the exception of patients with ocular symptoms. Prescribed treatments were comparable in hypothesis- and data-driven analyses. The prevalence of uncontrolled patients during treatment was similar in the 4 clusters, but was significantly different according to the ARIA classes. Cluster analysis using demographic and clinical parameters only does not appear to add relevant information for disease stratification in allergic rhinitis. © 2015 S. Karger AG, Basel.

  19. Relevance of cohort studies for the study of transplant infectious diseases.

    Berger, Christoph; Boggian, Katia; Cusini, Alexia; van Delden, Christian; Garzoni, Christian; Hirsch, Hans H; Khanna, Nina; Koller, Michael; Manuel, Oriol; Meylan, Pascal; Nadal, David; Weisser, Maja; Mueller, Nicolas J


    The debate on the merits of observational studies as compared with randomized trials is ongoing. We will briefly touch on this subject, and demonstrate the role of cohort studies for the description of infectious disease patterns after transplantation. The potential benefits of cohort studies for the clinical management of patients outside of the expected gain in epidemiological knowledge are reviewed. The newly established Swiss Transplantation Cohort Study and in particular the part focusing on infectious diseases will serve as an illustration. A neglected area of research is the indirect value of large, multicenter cohort studies. These benefits can range from a deepened collaboration to the development of common definitions and guidelines. Unfortunately, very few data exist on the role of such indirect effects on improving quality of patient management. This review postulates an important role for cohort studies, which should not be viewed as inferior but complementary to established research tools, in particular randomized trials. Randomized trials remain the least bias-prone method to establish knowledge regarding the significance of diagnostic or therapeutic measures. Cohort studies have the power to reflect a real-world situation and to pinpoint areas of knowledge as well as of uncertainty. Prerequisite is a prospective design requiring a set of inclusive data coupled with the meticulous insistence on data retrieval and quality.

  20. Experimental study on dynamic gas adsorption

    Qin Yueping; Wang Yaru; Yang Xiaobin; Liu Wei; Luo Wei


    In order to predict the actual adsorption amount as gas adsorption reaches the equilibrium,this research designed a dynamic gas adsorption experiment under constant temperature and pressure,and also studied the isopiestic adsorption characteristics of coal samples with same quality but different sizes.Through the experiment,the study found the adsorption-time changing relationships under different pressures of four different size samples.After regression analysis,we obtained the functional relationship between adsorption and time.According to this,the research resulted in the actual adsorption amount when gas adsorption reaches the equilibrium.In addition,the current study obtained the relationship between adsorption and pressure as well as the effect of the coal size to the adsorption rate.These results have great theoretical and practical significance for the prediction of gas amount in coal seam and gas adsorption process.

  1. Experimental studies on bioactive potential of rutin

    Shagun Dubey


    Full Text Available Background: Plant-derived phytochemicals are gaining wide popularity owing to their diverse therapeutic potential and less side effects. Rutin is one of the plant-derived flavonoid. Rutin has demonstrated cardio protective, analgesic, and anticancer effects. Aim: The current work was focused to evaluate bioactive potential of rutin. Materials and Methods: Rutin was isolated from tobacco leaves. The structure was confirmed by H 1 NMR spectroscopy. The isolated rutin was studied for possible antibacterial, antifungal, anthelmintic, larvicidal, and cytotoxic effects. Results: Results of studies demonstrated that rutin effectively inhibited growth of bacteria and fungi, as well as demonstrated anthelmintic potential. There was a positive response for larvicidal and cytotoxic effects. Conclusion: These studies justify chemotherapeutic potential of rutin.

  2. Experimental studies of actinides in molten salts

    Reavis, J.G.


    This review stresses techniques used in studies of molten salts containing multigram amounts of actinides exhibiting intense alpha activity but little or no penetrating gamma radiation. The preponderance of studies have used halides because oxygen-containing actinide compounds (other than oxides) are generally unstable at high temperatures. Topics discussed here include special enclosures, materials problems, preparation and purification of actinide elements and compounds, and measurements of various properties of the molten volts. Property measurements discussed are phase relationships, vapor pressure, density, viscosity, absorption spectra, electromotive force, and conductance. 188 refs., 17 figs., 6 tabs.

  3. Litigation and audit quality; two experimental studies

    Dijk, M. van


    This study examines the effect of litigation risk on auditors' willingness to yield to management pressure and to omit audit steps of the audit program in case of budget pressure. The results show that litigation risk has a significant impact on audit quality.

  4. Incisional Hernia: An Experimental and Clinical Study

    M. van 't Riet (Martijne)


    markdownabstract__Abstract__ Incisional hernia is one of the most common long-term complications of abdominal surgery. In prospective studies with sufficient follow-up, incidences of incisional hernia after laparotomy up to 20% are reported. Incisional hernia can be defined as an internal abdominal

  5. Glass polymorphism in glycerol-water mixtures: II. Experimental studies.

    Bachler, Johannes; Fuentes-Landete, Violeta; Jahn, David A; Wong, Jessina; Giovambattista, Nicolas; Loerting, Thomas


    We report a detailed experimental study of (i) pressure-induced transformations in glycerol-water mixtures at T = 77 K and P = 0-1.8 GPa, and (ii) heating-induced transformations of glycerol-water mixtures recovered at 1 atm and T = 77 K. Our samples are prepared by cooling the solutions at ambient pressure at various cooling rates (100 K s(-1)-10 K h(-1)) and for the whole range of glycerol mole fractions, χ(g). Depending on concentration and cooling rates, cooling leads to samples containing amorphous ice (χg ≥ 0.20), ice (χ(g) ≤ 0.32), and/or "distorted ice" (0 density amorphous ice (HDA). PIA of ice domains within the glycerol-water mixtures is shown to be possible only up to χ(g) ≈ 0.32 (T = 77 K). This is rather surprising since it has been known that at χ(g) solution of χ(g) ≈ 0.38. Accordingly, in the range 0.32 density amorphous ice) transformation. At 0.15 glycerol-water domains and, finally, the melting of ice at high temperatures. Our work exemplifies the complex "phase" behavior of glassy binary mixtures due to phase-separation (ice formation) and polyamorphism, and the relevance of sample preparation, concentration as well as cooling rates. The presence of the distorted ice (called "interphase" by us) also explains the debated "drift anomaly" upon melting. These results are compatible with the high-pressure study by Suzuki and Mishima indicating disappearance of polyamorphism at P ≈ 0.03-0.05 GPa at χ(g) ≈ 0.12-0.15 [J. Chem. Phys., 2014, 141, 094505].

  6. Experimental study of highly viscous impinging jets

    Gomon, M. [Univ. of Texas, Austin, TX (United States). Dept. of Mechanical Engineering


    The objective of this research is to study the behavior of highly viscous gravity-driven jets filling a container. Matters of interest are the formation of voids in the fluid pool during the filling process and the unstable behavior of the fluid in the landing region which manifests itself as an oscillating motion. The working fluids used in this research are intended to simulate the flow behavior of molten glass. Qualitative and quantitative results are obtained in a parametric study. The fraction of voids present in the fluid pool after the filling of the container is measured for different parameter values of viscosity and mass flow rate. Likewise, frequencies of the oscillating jet are measured. Results are inconclusive with regard to a correlation between parameter settings and void fractions. As for frequencies, power law correlations are established.

  7. Theoretical and Experimental Studies in Reactive Scattering.


    containing He and the neutral beam formed, cleansed of ions by appropriate electrostatic deflection plates, is reionized in a second charge exchange...H3 (having D3h symmetry) which could therefore support bound states. The technique of neutralization and reionization of H’ in order to study H 3 was...technique has been used again recently by Gaillard and co-workers 7 . By placing an electric field between the neutralization and reionization gas cells they

  8. Research on Hygiene Based on Fieldwork and Experimental Studies.

    Yajima, Ichiro


    Several experimental studies on hygiene have recently been performed and fieldwork studies are also important and essential tools. However, the implementation of experimental studies is insufficient compared with that of fieldwork studies on hygiene. Here, we show our well-balanced implementation of both fieldwork and experimental studies of toxic-element-mediated diseases including skin cancer and hearing loss. Since the pollution of drinking well water by toxic elements induces various diseases including skin cancer, we performed both fieldwork and experimental studies to determine the levels of toxic elements and the mechanisms behind the development of toxic-element-related diseases and to develop a novel remediation system. Our fieldwork studies in several countries including Bangladesh, Vietnam and Malaysia demonstrated that drinking well water was polluted with high concentrations of several toxic elements including arsenic, barium, iron and manganese. Our experimental studies using the data from our fieldwork studies demonstrated that these toxic elements caused skin cancer and hearing loss. Further experimental studies resulted in the development of a novel remediation system that adsorbs toxic elements from polluted drinking water. A well-balanced implementation of both fieldwork and experimental studies is important for the prediction, prevention and therapy of toxic-element-mediated diseases.

  9. The Power of Phase I Studies to Detect Clinical Relevant QTc Prolongation: A Resampling Simulation Study

    Georg Ferber


    Full Text Available Concentration-effect (CE models applied to early clinical QT data from healthy subjects are described in the latest E14 Q&A document as promising analysis to characterise QTc prolongation. The challenges faced if one attempts to replace a TQT study by thorough ECG assessments in Phase I based on CE models are the assurance to obtain sufficient power and the establishment of a substitute for the positive control to show assay sensitivity providing protection against false negatives. To demonstrate that CE models in small studies can reliably predict the absence of an effect on QTc, we investigated the role of some key design features in the power of the analysis. Specifically, the form of the CE model, inclusion of subjects on placebo, and sparse sampling on the performance and power of this analysis were investigated. In this study, the simulations conducted by subsampling subjects from 3 different TQT studies showed that CE model with a treatment effect can be used to exclude small QTc effects. The number of placebo subjects was also shown to increase the power to detect an inactive drug preventing false positives while an effect can be underestimated if time points around tmax are missed.

  10. Guidance on assessing the methodological and reporting quality of toxicologically relevant studies: A scoping review.

    Samuel, Gbeminiyi O; Hoffmann, Sebastian; Wright, Robert A; Lalu, Manoj Mathew; Patlewicz, Grace; Becker, Richard A; DeGeorge, George L; Fergusson, Dean; Hartung, Thomas; Lewis, R Jeffrey; Stephens, Martin L


    Assessments of methodological and reporting quality are critical to adequately judging the credibility of a study's conclusions and to gauging its potential reproducibility. To aid those seeking to assess the methodological or reporting quality of studies relevant to toxicology, we conducted a scoping review of the available guidance with respect to four types of studies: in vivo and in vitro, (quantitative) structure-activity relationships ([Q]SARs), physico-chemical, and human observational studies. Our aims were to identify the available guidance in this diverse literature, briefly summarize each document, and distill the common elements of these documents for each study type. In general, we found considerable guidance for in vivo and human studies, but only one paper addressed in vitro studies exclusively. The guidance for (Q)SAR studies and physico-chemical studies was scant but authoritative. There was substantial overlap across guidance documents in the proposed criteria for both methodological and reporting quality. Some guidance documents address toxicology research directly, whereas others address preclinical research generally or clinical research and therefore may not be fully applicable to the toxicology context without some translation. Another challenge is the degree to which assessments of methodological quality in toxicology should focus on risk of bias - as in clinical medicine and healthcare - or be broadened to include other quality measures, such as confirming the identity of test substances prior to exposure. Our review is intended primarily for those in toxicology and risk assessment seeking an entry point into the extensive and diverse literature on methodological and reporting quality applicable to their work.

  11. Clinical relevance of studies on the accuracy of visual inspection for detecting caries lesions: a systematic review.

    Gimenez, Thais; Piovesan, Chaiana; Braga, Mariana M; Raggio, Daniela P; Deery, Chris; Ricketts, David N; Ekstrand, Kim R; Mendes, Fausto Medeiros


    Although visual inspection is the most commonly used method for caries detection, and consequently the most investigated, studies have not been concerned about the clinical relevance of this procedure. Therefore, we conducted a systematic review in order to perform a critical evaluation considering the clinical relevance and methodological quality of studies on the accuracy of visual inspection for assessing caries lesions. Two independent reviewers searched several databases through July 2013 to identify papers/articles published in English. Other sources were checked to identify unpublished literature. The eligible studies were those which (1) assessed the accuracy of the visual method for detecting caries lesions on occlusal, approximal or smooth surfaces, in primary or permanent teeth, (2) used a reference standard, and (3) reported data about sample size and accuracy of the methods. Aspects related to clinical relevance and the methodological quality of the studies were evaluated. 96 of the 5,578 articles initially identified met the inclusion criteria. In general, most studies failed in considering some clinically relevant aspects: only 1 included study validated activity status of lesions, no study considered its prognosis, 79 studies did not consider a clinically relevant outcome, and only 1 evaluated a patient-centred outcome. Concerning methodological quality, the majority of the studies presented a high risk of bias in sample selection. In conclusion, studies on the accuracy of the visual method for caries detection should consider clinically relevant outcomes besides accuracy; moreover, they should be conducted with higher methodological quality, mainly regarding sample selection.

  12. Review of relevant studies of isolated systems[Integration of wind energy

    Hansen, L.H.; Lundsager, P.


    The report presents the results of a review of studies relating to integration of wind energy in isolated power supply systems, based on a systematic literature survey. The purpose of the study is to develop a methodology consisting of a set of guidelines for wind energy projects in isolated energy systems and a set of tools and models that are operational on an engineering level. The review is based on a literature search in the ETDE Energy Database with a main search covering the period 7/88 to 6/97 and supplemented by partial update periods. A few newer references have been included in the review, most notably the IEC/PAS 62111 specification. The amount of wind energy literature related to the subject is excessively large, and a complete review in which every relevant abstract is identified and examined is not feasible within the framework of this (or probably any other) study. The review results have been organised according to the following keywords: methods & guides, economics, concept of application, system solutions, case studies, financial programmes, dedicated software tools. None of the found references presents methods or tools that contradict the philosophy of Risoe's methodology as it is described in the report. It is therefore concluded that Risoe's methodology makes a good platform for further development. (au)

  13. Experimental study on a simplified crossflow turbine

    Chiyembekezo S. Kaunda, Cuthbert Z. Kimambo, Torbjorn K. Nielsen


    Full Text Available The main aim of the study is to enhance the design of a Crossflow turbine, as an appropriate technology for small-scale power generation. This study evaluates the performance of a simplified Crossflow turbine at conditions other than the ‘best efficiency point’. It also explores the ‘reaction’ behavior of the Crossflow turbine as well as characterizes the torque transfer in the two stages of the turbine. The experiments were conducted on a physical simplified Crossflow turbine model using the test facilities in the Waterpower Laboratory at the Norwegian University of Science and Technology. The results show that the maximum turbine efficiency is 79%, achieved at a head of 5m and reduced speed of 13.4; making it a low speed turbine. This turbine efficiency compares well with some reported efficiency values. The result also show that the turbine is efficient when it operates with a degree of reaction and this is achieved at large valve openings; validating observations that the Crossflow turbine is not a pure impulse turbine. Performance evaluation outside the best efficiency point shows that the efficiency decreases with increase in head above the best efficiency head. The turbine efficiency is not sensitive to flow variations: except at a head of 3m, at all tested heads, 25% of the flow at best efficiency point still generates efficiency of above 50%. Torque characterization shows that the second stage plays a significant role in torque transfer, especially when at large valve openings. Therefore, design efforts must also look at how the flow inside the runner interior space can be controlled so that the jet enters the second stage with optimum flow angles. The use of strain gauge to characterize the torque produced using momentum principle as employed in this study presents an additional opportunity to analyze the trends in the torque transfer.

  14. Experimental study of relative, turbulent diffusion

    Mann, J.; Ott, Søren; Andersen, J.S.


    The purpose is to study relative turbulent diffusion under controlled, reproducible conditions in the laboratory in order to estimate the constant C in Richardson-Obukhov's law. We get C #approx# 0.4 -- 0.6. We furthermore measure the distance-neighbourfunction, which is the probability density...... system with two computers each equipped with a frame grabber card. In the search for the best experimentalmethods we have revised the concept of local homogeneity and derived a law for the velocity--acceleration structure function. A second by-product of this effort is a relatively simple derivation...

  15. Experimental study of a solar still

    Hassoun, Z. Sari; Aliane, K.; Berrezoug, H. I.


    This work concerns the study of a solar distiller. Particular attention is paid to the different operating characteristics such as: temperature, global and internal efficiency, performance and the performance factor during the distillation process. We have also established the overall heat balance in transition. A series of tests was carried out during the summer under the sea water to see the evolution of different parameters of the distiller. The daily output of solar still is 1.8litre / day. All the dissolved solids (TDS), conductivity and pH of the water were measured.

  16. The class inclusion question: a case study in applying pragmatics to the experimental study of cognition.

    Politzer, Guy


    For more than 70 years, Piaget's class-inclusion task (given, e.g., five asters and three tulips, the child is asked whether "there are more asters or more flowers") has been the object of experimental investigation. Inclusion is of considerable importance for cognitive science as it is a key concept for logical operations and knowledge representation. It is shown that the question can be characterised by a kind of privative ambiguity which is at the source of the younger children's answer, "more asters". A relevance-theoretic explanation of children's interpretation of the question and of the subsequent responses is expounded. This account can explain the effect of all the factors that are known to influence performance (e.g., role of collections, counting, typicality, qualification, syntax, etc.), a review of which is presented. It is further tested experimentally. The development of performance is explained on the basis of the way children disambiguate the question. This study exemplifies the two ways in which pragmatic analysis is pertinent to the study of children's (as well as adults') reasoning and judgement, namely in explaining and predicting participants' comprehension of the statements and questions, and in taking into account attribution processes that occur in the experimental setting.

  17. Experimental Study of Fractal Image Compression Algorithm

    Chetan R. Dudhagara


    Full Text Available Image compression applications have been increasing in recent years. Fractal compression is a lossy compression method for digital images, based on fractals. The method is best suited for textures and natural images, relying on the fact that parts of an image often resemble other parts of the same image. In this paper, a study on fractal-based image compression and fixed-size partitioning will be made, analyzed for performance and compared with a standard frequency domain based image compression standard, JPEG. Sample images will be used to perform compression and decompression. Performance metrics such as compression ratio, compression time and decompression time will be measured in JPEG cases. Also the phenomenon of resolution/scale independence will be studied and described with examples. Fractal algorithms convert these parts into mathematical data called "fractal codes" which are used to recreate the encoded image. Fractal encoding is a mathematical process used to encode bitmaps containing a real-world image as a set of mathematical data that describes the fractal properties of the image. Fractal encoding relies on the fact that all natural, and most artificial, objects contain redundant information in the form of similar, repeating patterns called fractals.

  18. [An experimental study on freudian slips].

    Köhler, Thomas; Simon, Patrick


    We attempted to replicate findings of a frequently cited study by Motley. This author had used a tachistoskope to present his participants pairs of words which had a meaning after exchanging the initial letters of each word ("spoonerisms"). In accordance with the psychoanalytic theory of Freudian slips, Motley was able to show that under the impression of a sexually stimulating situation more sexual words were read; under the threat of electric shock spoonerisms appeared more often in words with reference to electricity. In our study we tried to induce spoonerisms by presentation of short written texts of erotic, aggressive and neutral content. It could be shown that after reading the erotic and the aggressive text, slips were produced more often than following the text of neutral content. In addition, significantly more slips of erotic kind occurred after reading the erotic text, whereas more aggressive slips were observed immediately after lecture of the text with aggressive content. We were therefore able to replicate Motley's findings and thus also corroborated assumptions made by Freud on the origin of slips of the tongue.

  19. Acrolein and embryogenesis: an experimental study

    Chhibber, G.; Cilani, S.H.


    The effects of acrolein were studied on the chick embryos of 48 and 72 hr of incubation. Acrolein was dissolved in physiological saline and injected into the air sacs of the eggs at doses ranging from 0.001 to 0.1 mg per egg. The controls received and equal amount of saline only (0.1 ml per egg). All the embryos including controls were examined at Day 13. In all, 600 eggs were utilized for this investigation. At 48 hr incubation, the percentage survival ranged from 80 to 0 as the dosage of acrolein was increased. Embryonic mortality following 72 hr incubation did not increase significantly at any dose level. Gross malformations such as short and twisted limbs, everted viscera, microphthalmia, short and twisted neck, and hemorrhage over the body were observed. The frequency and the types of gross abnormalities did not vary much in the 48- or 72-hr-treated groups. The incidence of malformation in the controls was low. The results of this study indicates that acrolein is embryotoxic at higher doses and moderately teratogenic to chick embryogenesis.

  20. Achieving Rigour and Relevance in Information Systems Studies: Using grounded theory to investigate organizational cases

    Hans Lehmann, Ph.D.


    Full Text Available This paper builds on the belief that rigorous Information Systems (IS research can help practitioners to better understand and to adapt to emerging situations. Contrary to the view seeing rigour and relevance as a dichotomy, it is maintained that IS researchers have a third choice; namely, to be both relevant and rigorous. The paper proposes ways in which IS research can contribute to easing the practitioners’ burden of adapting to changes by providing timely, relevant, and rigorous research. It is argued that synergy between relevance and rigour is possible and that classic grounded theory methodology in combination with case-based data provides a good framework for rigorous and relevant research of emerging phenomena in information systems.

  1. Experimental techniques for cement hydration studies

    Andreas Luttge


    Full Text Available Cement hydration kinetics is a complex problem of dissolution, nucleation and growth that is still not well understood, particularly in a quantitative way. While cement systems are unique in certain aspects they are also comparable to natural mineral systems. Therefore, geochemistry and particularly the study of mineral dissolution and growth may be able to provide insight and methods that can be utilized in cement hydration research. Here, we review mainly what is not known or what is currently used and applied in a problematic way. Examples are the typical Avrami approach, the application of Transition State Theory (TST to overall reaction kinetics and the problem of reactive surface area. Finally, we suggest an integrated approach that combines vertical scanning interferometry (VSI with other sophisticated analytical techniques such as atomic force microscopy (AFM and theoretical model calculations based on a stochastic treatment.

  2. Experimental study on phase perception in speech

    BU Fanliang; CHEN Yanpu


    As the human ear is dull to the phase in speech, little attention has been paid tophase information in speech coding. In fact, the speech perceptual quality may be degeneratedif the phase distortion is very large. The perceptual effect of the STFT (Short time Fouriertransform) phase spectrum is studied by auditory subjective hearing tests. Three main con-clusions are (1) If the phase information is neglected completely, the subjective quality of thereconstructed speech may be very poor; (2) Whether the neglected phase is in low frequencyband or high frequency band, the difference from the original speech can be perceived by ear;(3) It is very difficult for the human ear to perceive the difference of speech quality betweenoriginal speech and reconstructed speech while the phase quantization step size is shorter thanπ/7.

  3. Experimental Studies of Top Quark Production

    Wagner-Kuhr, Jeannine


    In this review article three promising aspects of top quark production are discussed: the charge asymmetry in top quark pair production, the search for resonant top quark pair production, and electroweak single top quark production. First, an overview of the theoretical predictions of top quark pair and single top quark production is given. Then, for each topic the general analysis strategy and improvements are exemplarily explained using selected analyses and are put into the context of the global status at the beginning of LHC Run II and progress in this field. The example analyses discussed in more detail in this article use data from the LHC experiment CMS and for the charge asymmetry studies also data from the Tevatron experiment CDF have been used.

  4. Patterns of power communication: an experimental study

    Kali Prasad


    Full Text Available "Communication in one form or others is the basis of all social interaction. This paper deals with a particular aspect of communication namely, the effect of power and authority on the communication patterns that are set up between individuals. In such situation usually a power differential exists between the individuals as in the case of an employer and an employee, and this is responsible for setting up different attitudes in the mind of the people. The aim of the experiment described here is to study the reactions in individuals to expression of praise and hostility. The main finding is that those who are in power e.g. the employers are not so susceptible to praise as those who are subordinate to them. Also, a superior power person is less disturbed by hostile act of a subordinate than vice versa.

  5. Experimental Study of Lunar and SNC Magmas

    Rutherford, Malcolm J.


    The research described in this progress report involved the study of petrological, geochemical, and volcanic processes that occur on the Moon and the SNC meteorite parent body, generally accepted to be Mars. The link between these studies is that they focus on two terrestrial-type parent bodies somewhat smaller than earth, and the fact that they focus on the types of magmas (magma compositions) present, the role of volatiles in magmatic processes, and on processes of magma evolution on these planets. We are also interested in how these processes and magma types varied over time.In earlier work on the A15 green and A17 orange lunar glasses, we discovered a variety of metal blebs. Some of these Fe-Ni metal blebs occur in the glass; others (in A17) were found in olivine phenocrysts that we find make up about 2 vol 96 of the orange glass magma. The importance of these metal spheres is that they fix the oxidation state of the parent magma during the eruption, and also indicate changes during the eruption . They also yield important information about the composition of the gas phase present, the gas that drove the lunar fire-fountaining. During the tenure of this grant, we have continued to work on the remaining questions regarding the origin and evolution of the gas phase in lunar basaltic magmas, what they indicate about the lunar interior, and how the gas affects volcanic eruptions. Work on Martian magmas petrogenesis questions during the tenure of this grant has resulted in advances in our methods of evaluating magmatic oxidation state variations in Mars and some new insights into the compositional variations that existed in the SNC magmas over time . Additionally, Minitti has continued to work on the problem of possible shock effects on the abundance and distribution of water in Mars minerals.

  6. A Pilot Study of Ion - Molecule Reactions at Temperatures Relevant to the Atmosphere of Titan

    Zymak, Illia; Žabka, Ján; Polášek, Miroslav; Španěl, Patrik; Smith, David


    Reliable theoretical models of the chemical kinetics of the ionosphere of Saturn's moon, Titan, is highly dependent on the precision of the rates of the reactions of ambient ions with hydrocarbon molecules at relevant temperatures. A Variable Temperature Selected Ions Flow Tube technique, which has been developed primarily to study these reactions at temperatures within the range of 200-330 K, is briefly described. The flow tube temperature regulation system and the thermalisation of ions are also discussed. Preliminary studies of two reactions have been carried out to check the reliability and efficacy of kinetics measurements: (i) Rate constants of the reaction of CH3 + ions with molecular oxygen were measured at different temperatures, which indicate values in agreement with previous ion cyclotron resonance measurements ostensibly made at 300 K. (ii) Formation of CH3 + ions in the reaction of N2 + ions with CH4 molecules were studied at temperatures within the range 240-310 K which showed a small but statistically significant decrease of the ratio of product CH3 + ions to reactant N2 + ions with reaction temperature.

  7. The relevance of VDRL as routine test in pregnant women: a critcal study.

    Ikeme, A C C; Okeke, T C


    To critically determine the relevance of Venereal Diseases Research Laboratories (VDRL) investigation as a routine serological screening for syphilis among pregnant women who receive antenatal care at the University of Nigeria Teaching Hospital (UNTH). A retrospective chart review of result of serological test for syphilis among pregnant women during a five year period (1st January, 1997 to 31st December 2001) was undertaken. A total of 7469 women booked. 7175 had routine serological test. 294 of the booked women failed to submit themselves for screening. The prevalence rate of syphilis in this study was 0.125%. VDRL seroreactivity had in previous studies in this center declined from 3.06% to 1.30%. It further declined to 0.98% in this study. The results strongly show a continuing very low prevalence rate of syphilis in Enugu. Nevertheless, we support continued screening of pregnant women inspite of this low prevalence rate, since this will eradicated the effects of undiagnosed and untreated syphilis.

  8. Experimental Study on Hydrocarbon Fuel Thermal Stability

    J.S.Chin; A.H.Lefebvre


    The-thermal stability characteristics of kerosine-type fuels are examined using a heated-tube apparatus which allows independent control of fuel pressure,fuel temperature,tube-wall temperature and fuel flow rate.This method is identified simply as a "constant wall temperature method”,It is different from a previous widely used method ,which is identified as a “Constant heat flux method”,It is a single-pass system.Rate of deposition on the tube walls are measured by weighing the test tube before and after each test.For a fuel temperature of 250℃,it is found that deposition rates increease continuously with increase in tubewall temperature.This finding contradicts the results of previous studies which had led to the conclusion that deposition rates increase with increase in wall temperature up to a certain value(around 650K) beyond which any further increase in wall temperature causes the rate of deposition to decline.The present results show clearly that the constant wall temperature method is more suitable for assessing the thermal stability of gas turbine fuels.


    Igor WACHTER


    Full Text Available The aim of this scientific paper is an analysis of the minimum ignition temperature of dust layer and the minimum ignition temperatures of dust clouds. It could be used to identify the threats in industrial production and civil engineering, on which a layer of combustible dust could occure. Research was performed on spent coffee grounds. Tests were performed according to EN 50281-2-1:2002 Methods for determining the minimum ignition temperatures of dust (Method A. Objective of method A is to determine the minimum temperature at which ignition or decomposition of dust occurs during thermal straining on a hot plate at a constant temperature. The highest minimum smouldering and carbonating temperature of spent coffee grounds for 5 mm high layer was determined at the interval from 280 °C to 310 °C during 600 seconds. Method B is used to determine the minimum ignition temperature of a dust cloud. Minimum ignition temperature of studied dust was determined to 470 °C (air pressure – 50 kPa, sample weight 0.3 g.

  10. Antithrombotic activity of argan oil: an in vivo experimental study.

    Mekhfi, Hassane; Belmekki, Fatima; Ziyyat, Abderrahim; Legssyer, Abdelkhaleq; Bnouham, Mohamed; Aziz, Mohammed


    Argan oil has been shown to inhibit in vitro and ex vivo platelet aggregation without extending bleeding time. In this report, we examined in vivo the antithrombotic activity of argan oil in an experimental thrombosis model in mice: acute pulmonary thromboembolism and in vitro its effect in a coagulation assay. Acute pulmonary thromboembolism was induced, after argan oil treatment, by an intravenous injection of a collagen and epinephrine mixture. The paralyzed and dead mice in each group were numbered and the percentage of protection against acute pulmonary thromboembolism was calculated. The histologic study was conducted in lung tissue to estimate the percentage of opened and occluded vessels by platelet thrombi. The coagulation assay was monitored in platelet-poor plasma from normal rats by measuring the clotting parameters (activated partial thromboplastin time, prothrombin time, and thrombin time) in the presence and absence of argan oil. Argan oil (1 mL/100 g/day), administered orally, showed an antithrombotic activity preventing the paralysis or death (50%) induced by the collagen-epinephrine intravenous injection. This observation was confirmed by the lung histologic examination, in which the density of occluded blood vessels was significantly decreased (62.16 ± 3.95%). However, the argan oil remained inactive for the coagulation parameters of activated partial thromboplastin time, prothrombin time, and thrombin time at variance with heparin, an anticoagulant reference drug. The antithrombotic activity of argan oil seemed unrelated to the anticoagulant activity. We suggest that argan oil might be an interesting natural dietary source for the nutritional prevention of hemostasis and cardiovascular disorders. Clinical trials would be necessary and relevant to confirm this hypothesis. Copyright © 2012 Elsevier Inc. All rights reserved.

  11. Experimental developments for the study of explosive nucleosynthesis in stars

    Erikson, Luke

    For several years now, the n-SNS collaboration has been working to place a small neutrino detector at the Spallation Neutron Source at Oak Ridge National Lab. If successful, the experiment may produce the needed neutrino-nucleus cross sections on solid targets such as iron and aluminum. These reaction probabilities are of great interest for a number of reasons, including: neutrino astronomy, explosive nucleosynthesis, and nuclear structure. However, success for this project requires a very efficient cosmic ray detector to exclude backgrounds. The system would need to be ~99% efficient while remaining affordable in a difficult financial climate for basic science. The first half of this thesis addresses a prototype cosmic ray veto based on extruded scintillator with embedded wave-length-shifting fibers. This approach has been successfully used before, and may provide the performance needed for this project. However, our results suggest some additional research and development would be required to meet the requirements for the n-SNS experiment. The second half of this thesis relates to experimental work to study the resonance strength of the 23 Mg(p,g) 24 Al reaction. For this purpose a radioactive ion beam experiment has been conducted at TRIUMF using the DRAGON experiment. This reaction is thought to play an important role during explosive nucleosynthesis such as novae and X-ray bursts. If so, then accurate knowledge of this break-out reaction would help explain the isotopic abundances around that mass range in the universe. Our results suggest the rate of this reaction at astrophysically relevant energies is lower than predicted and might further exclude explosive binary systems as the production site for such elements as 26 Al.

  12. Markets and morals: an experimental survey study.

    Julio J Elias

    Full Text Available Most societies prohibit some market transactions based on moral concerns, even when the exchanges would benefit the parties involved and would not create negative externalities. A prominent example is given by payments for human organs for transplantation, banned virtually everywhere despite long waiting lists and many deaths of patients who cannot find a donor. Recent research, however, has shown that individuals significantly increase their stated support for a regulated market for human organs when provided with information about the organ shortage and the potential beneficial effects a price mechanism. In this study we focused on payments for human organs and on another "repugnant" transaction, indoor prostitution, to address two questions: (A Does providing general information on the welfare properties of prices and markets modify attitudes toward repugnant trades? (B Does additional knowledge on the benefits of a price mechanism in a specific context affect attitudes toward price-based transactions in another context? By answering these questions, we can assess whether eliciting a market-oriented approach may lead to a relaxation of moral opposition to markets, and whether there is a cross-effect of information, in particular for morally controversial activities that, although different, share a reference to the "commercialization" of the human body. Relying on an online survey experiment with 5,324 U.S. residents, we found no effect of general information about market efficiency, consistent with morally controversial markets being accepted only when they are seen as a solution to a specific problem. We also found some cross-effects of information about a transaction on the acceptance of the other; however, the responses were mediated by the gender and (to a lesser extent religiosity of the respondent--in particular, women exposed to information about legalizing prostitution reduced their stated support for regulated organ payments. We

  13. Markets and morals: an experimental survey study.

    Elias, Julio J; Lacetera, Nicola; Macis, Mario


    Most societies prohibit some market transactions based on moral concerns, even when the exchanges would benefit the parties involved and would not create negative externalities. A prominent example is given by payments for human organs for transplantation, banned virtually everywhere despite long waiting lists and many deaths of patients who cannot find a donor. Recent research, however, has shown that individuals significantly increase their stated support for a regulated market for human organs when provided with information about the organ shortage and the potential beneficial effects a price mechanism. In this study we focused on payments for human organs and on another "repugnant" transaction, indoor prostitution, to address two questions: (A) Does providing general information on the welfare properties of prices and markets modify attitudes toward repugnant trades? (B) Does additional knowledge on the benefits of a price mechanism in a specific context affect attitudes toward price-based transactions in another context? By answering these questions, we can assess whether eliciting a market-oriented approach may lead to a relaxation of moral opposition to markets, and whether there is a cross-effect of information, in particular for morally controversial activities that, although different, share a reference to the "commercialization" of the human body. Relying on an online survey experiment with 5,324 U.S. residents, we found no effect of general information about market efficiency, consistent with morally controversial markets being accepted only when they are seen as a solution to a specific problem. We also found some cross-effects of information about a transaction on the acceptance of the other; however, the responses were mediated by the gender and (to a lesser extent) religiosity of the respondent--in particular, women exposed to information about legalizing prostitution reduced their stated support for regulated organ payments. We relate these

  14. Medical waste to energy: experimental study.

    Arcuri, C; Luciani, F; Piva, P; Bartuli, F N; Ottria, L; Mecheri, B; Licoccia, S


    Although waste is traditionally assessed as a pollutant which needs to be reduced or lessened, its management is certainly necessary. Nowadays, biological fuel cells, through the direct conversion of organic matter to electricity using biocatalysts, represent a technology able to produce sustainable energy by means of waste treatment. This study aims to propose a mean to generate energy from blood and saliva, that are common risk-infectious medical waste. Material employed (purchased by Sigma-Aldrich) were: Glucose oxidase (GOx), Nafion perfluorinated resin solution at 5% in a mixture of lower aliphatic alcohols and water, Polyethylene oxide. Stock solutions of D (+) glucose were prepared in a 0.1 M phosphate buffer solution and stored at 4 °C for at least 24 h before use. Carbon cloth electrode ELAT HT 140 E-W with a platinum loading of 5 gm-2 was purchased by E-Tek. Electrospun Nafion fibers were obtained as follows. Scanning electron microscopy was used to characterize the electrode morphologies. In order to develop an effective immobilization strategy of GOx on the electrode surface, Nafion fibers (a fully fluorinated ion conducting polymer used as a membrane material in enzymatic fuel cells - EFC) were selected as immobilizing polymer matrix. In this work, exploiting the nafion fibers capability of being able to cathalize Gox activity, we have tried to produce an enzymatic fuel cell which could produce energy from the blood and the saliva within medical-dental waste. Medical waste refers to all those materials produced by the interaction among doctor and patient, such as blood and saliva. During our research we will try to complete an EFC prototype able to produce energy from blood and saliva inside the risk-infectious medical waste in order to contribute to the energy requirements of a consulting room.

  15. Markets and Morals: An Experimental Survey Study

    Elias, Julio J.; Lacetera, Nicola; Macis, Mario


    Most societies prohibit some market transactions based on moral concerns, even when the exchanges would benefit the parties involved and would not create negative externalities. A prominent example is given by payments for human organs for transplantation, banned virtually everywhere despite long waiting lists and many deaths of patients who cannot find a donor. Recent research, however, has shown that individuals significantly increase their stated support for a regulated market for human organs when provided with information about the organ shortage and the potential beneficial effects a price mechanism. In this study we focused on payments for human organs and on another “repugnant” transaction, indoor prostitution, to address two questions: (A) Does providing general information on the welfare properties of prices and markets modify attitudes toward repugnant trades? (B) Does additional knowledge on the benefits of a price mechanism in a specific context affect attitudes toward price-based transactions in another context? By answering these questions, we can assess whether eliciting a market-oriented approach may lead to a relaxation of moral opposition to markets, and whether there is a cross-effect of information, in particular for morally controversial activities that, although different, share a reference to the “commercialization” of the human body. Relying on an online survey experiment with 5,324 U.S. residents, we found no effect of general information about market efficiency, consistent with morally controversial markets being accepted only when they are seen as a solution to a specific problem. We also found some cross-effects of information about a transaction on the acceptance of the other; however, the responses were mediated by the gender and (to a lesser extent) religiosity of the respondent—in particular, women exposed to information about legalizing prostitution reduced their stated support for regulated organ payments. We relate

  16. Clinical relevance of comorbidity in anxiety disorders : A report from the Netherlands Study of Depression and Anxiety (NESDA)

    Hofmeijer-Sevink, Mieke Klein; Batelaan, Neeltje M.; van Megen, Harold J. G. M.; Penninx, Brenda W.; Cath, Danielle C.; van den Hout, Marcel A.; van Balkom, Anton J. L. M.

    Background: To study the clinical relevance of type of comorbidity and number of comorbid disorders in anxiety disorders. Four groups were compared according to sociodemographic-, vulnerability- and clinical factors: single anxiety disorder, anxiety-anxiety comorbidity, anxiety-depressive

  17. Clinical relevance of comorbidity in anxiety disorders : A report from the Netherlands Study of Depression and Anxiety (NESDA)

    Hofmeijer-Sevink, Mieke Klein; Batelaan, Neeltje M.; van Megen, Harold J. G. M.; Penninx, Brenda W.; Cath, Danielle C.; van den Hout, Marcel A.; van Balkom, Anton J. L. M.


    Background: To study the clinical relevance of type of comorbidity and number of comorbid disorders in anxiety disorders. Four groups were compared according to sociodemographic-, vulnerability- and clinical factors: single anxiety disorder, anxiety-anxiety comorbidity, anxiety-depressive comorbidit

  18. Clinical relevance of comorbidity in anxiety disorders : A report from the Netherlands Study of Depression and Anxiety (NESDA)

    Hofmeijer-Sevink, Mieke Klein; Batelaan, Neeltje M.; van Megen, Harold J. G. M.; Penninx, Brenda W.; Cath, Danielle C.; van den Hout, Marcel A.; van Balkom, Anton J. L. M.


    Background: To study the clinical relevance of type of comorbidity and number of comorbid disorders in anxiety disorders. Four groups were compared according to sociodemographic-, vulnerability- and clinical factors: single anxiety disorder, anxiety-anxiety comorbidity, anxiety-depressive comorbidit

  19. Theoretical and Experimental Studies in Accelerator Physics

    Rosenzweig, James [Univ. of California, Los Angeles, CA (United States). Dept. of Physics and Astronomy


    . We note also that PBPL graduates remain as close elaborators for the program after leaving UCLA. The UCLA PBPL program is a foremost developer of on-campus facilities, such as the Neptune and Pegasus Laboratories, providing a uniquely strong environment for student-based research. In addition, the PBPL is a strong user of off-campus national lab facilities, such as SLAC FACET and NLCTA, and the BNL ATF. UCLA has also vigorously participated in the development of these facilities. The dual emphases on off- and on-campus opportunities permit the PBPL to address in an agile way a wide selection of cutting-edge research topics. The topics embraced by this proposal illustrate this program aspect well. These include: GV/m dielectric wakefield acceleration/coherent Cerenkov radiation experiments at FACET (E-201) and the ATF; synergistic laser-excited dielectric accelerator and light source development; plasma wakefield (PWFA) experiments on “Trojan horse” ionization injection (FACET E-210), quasi-nonlinear PWFA at BNL and the production at Neptune high transformer ratio plasma wakes; the inauguration of a new type of RF photoinjector termed “hybrid” at UCLA, and application to PWFA; space-charge dominated beam and cathode/near cathode physics; the study of advanced IFEL systems, for very high energy gain and utilization of novel OAM modes; the physcis of inverse Compton scattering (ICS), with applications to e+ production and γγ colliders; electron diffraction; and advanced beam diagnostics using coherent imaging techniques. These subjects are addressed under the leadership of PBPL director Prof. James Rosenzweig in Task A, and Prof. Pietro Musumeci in Task J, which was initiated following his OHEP Outstanding Junior Investigator award.

  20. Injury Based on Its Study in Experimental Models

    M. Mendes-Braz


    Full Text Available The present review focuses on the numerous experimental models used to study the complexity of hepatic ischemia/reperfusion (I/R injury. Although experimental models of hepatic I/R injury represent a compromise between the clinical reality and experimental simplification, the clinical transfer of experimental results is problematic because of anatomical and physiological differences and the inevitable simplification of experimental work. In this review, the strengths and limitations of the various models of hepatic I/R are discussed. Several strategies to protect the liver from I/R injury have been developed in animal models and, some of these, might find their way into clinical practice. We also attempt to highlight the fact that the mechanisms responsible for hepatic I/R injury depend on the experimental model used, and therefore the therapeutic strategies also differ according to the model used. Thus, the choice of model must therefore be adapted to the clinical question being answered.

  1. Atomic spectroscopy on fusion relevant ions and studies of light impurities in the JET tokamak

    Tunklev, M


    The spectrum and energy levels of C IV and the 3l-4l system of the Mg-like ions in the iron group elements have been investigated. This has led to several hundred identified transitions, many of them previously unknown. Using the Charge Exchange Diagnostic system at JET, ion temperatures, rotation velocities and densities have been derived from visible spectroscopic measurements on fully ionised light impurities, such as He, C, N and Ne. The existence of plume contribution from beam produced hydrogen-like ions has been proven beyond any doubt to affect the deduction of the active charge exchange signal of He II. In the case of C VI the plume signal was estimated to be at least a factor of five lower than the active charge exchange signal. Line integrated passive charge exchange emission between neutral background atoms and fully stripped impurity ions has been investigated and modelled. When the synthetic spectrum is fitted into the experimentally detected spectra the neutral background density can be deduced. The importance of including background atoms (H, D and T) as charge exchange donors, not only in state 2s, but also in state 1s, has shown to be crucial in high temperature shots. Transport of light impurities has been studied with gas puff injections into steady state H-mode plasmas. The results suggest that light impurities are transported as described by the neo-classical Pfirsch-Schlueter regime at the edge, whilst in the centre, sawtoothing, preferably to Banana transport, is mixing the plasma and increases the measured values on the diffusion. For the peaking of impurities in a steady state plasma an anomalous treatment was more in agreement with the experimental data. Certain confinement information, previously predicted theoretically as a part of the peaking equation, has been experimentally verified

  2. An evaluation study on the relevance and effectiveness of training activities in Northern Uganda.

    Cicciò, Luigi; Makumbi, M; Sera, Diana


    In-service training is required for quality health service delivery, particularly in a human resource constrained setting. However, detailed evaluation of training effectiveness is rarely conducted because the improved theoretical knowledge demonstrated by trainees during training is commonly used as a proxy indicator of effectiveness. This study focused on a trained health workforce in Northern Uganda. The retention of specifically-trained staff 12-15 months after attending training was examined, as was the relevance and usefulness of the training as perceived by the health workers. This cross-sectional descriptive study used a structured questionnaire to interview 104 health workers (mainly paramedics) who received training in the Northern Uganda Malaria, AIDS & HIV and TB Program in the period July 2007 to February 2008. Of the 104 interviewed health workers, 71% were still deployed at the original work site at the time of the interview and 87% reported they found the training event attended to be useful. However, any form of follow up was provided to only 40% of respondents, and 25% reported having attended another similar training event on the same topic at some point in time. All programs with a substantial training component should conduct a periodic methodical evaluation of the training.

  3. Selected, annotated bibliography of studies relevant to the isolation of nuclear wastes. [705 references

    Hyder, L.K.; Fore, C.S.; Vaughan, N.D.; Faust, R.A.


    This annotated bibliography of 705 references represents the first in a series to be published by the Ecological Sciences Information Center containing scientific, technical, economic, and regulatory information relevant to nuclear waste isolation. Most references discuss deep geologic disposal, with fewer studies of deep seabed disposal; space disposal is also included. The publication covers both domestic and foreign literature for the period 1954 to 1980. Major chapters selected are Chemical and Physical Aspects; Container Design and Performance; Disposal Site; Envirnmental Transport; General Studies and Reviews; Geology, Hydrology and Site Resources; Regulatory and Economic Aspects; Repository Design and Engineering; Transportation Technology; Waste Production; and Waste Treatment. Specialized data fields have been incorporated to improve the ease and accuracy of locating pertinent references. Specific radionuclides for which data are presented are listed in the Measured Radionuclides field, and specific parameters which affect the migration of these radionuclides are presented in the Measured Parameters field. The references within each chapter are arranged alphabetically by leading author, corporate affiliation, or title of the document. When the author is not given, the corporate affiliation appears first. If these two levels of authorship are not given, the title of the document is used as the identifying level. Indexes are provided for author(s), keywords, subject category, title, geographic location, measured parameters, measured radionuclides, and publication description.

  4. A Case Study: Are Traditional Face-To-Face Lectures Still Relevant When Teaching Engineering Courses?

    LillAnne Jackson


    Full Text Available In this rapidly changing age, with virtually all information available on the Internet including courses, students may not find any reason to physically attend the lectures. In spite of the many benefits the online lectures and materials bring to teaching, this drift from the traditional (norm face-to-face lectures is also creating further barriers, such as difficulty in communicating and building personal relationships, between students and instructor. In this paper we carry out a study that presents and analyzes factors that motivate students to attend a (1 face-to-face instruction in-class versus an (2 online class. This study is based on an anonymous and voluntary survey that was conducted in the School of Engineering at University of Victoria, BC, Canada. This paper presents and shares the detailed results and analysis of this survey that also includes some interesting and useful comments from the students. Based on the results, analysis and comments the paper suggests methodologies of how to improve face-to-face in-class instructions to make them more relevant to the current global information age.

  5. Relevance of blood cultures in acute pyelonephritis in a single-center retrospective study.

    Ledochowski, Stanislas; Abraham, Paul-Samuel; Jacob, Xavier; Dumitrescu, Oana; Lina, Gérard; Lepape, Alain; Piriou, Vincent; Wallet, Florent; Friggeri, Arnaud


    Pyelonephritides are frequently encountered diagnosis in Emergency Departments. Urinalyses have a central place in the management of this situation but the usefulness of blood cultures is not clear. We conducted a single-center retrospective study of 24 months to study the microbiological relevance of blood cultures in pyelonephritis. We included patients with blood cultures (BC) and urine cultures (UC) drawn at the same time, if they were not exposed to antibiotics prior to these tests. Of our 264 patients, 39 (15 %) had no bacteriological documentation. There were 83 (31 %) bacteremic patients. Seven patients had contaminated or sterile UC with positive BC. Four patients had positive UC and BC with the latter allowing identification of a pathogen absent from the UC (n = 1) or identifying the main pathogen in three cases. A total of 11 patients theoretically benefited from BC representing 4.2 % of our population. Excluding one patient who was known to be infected with multi-drug resistant bacteria, all empirical antibiotics regimens were effective against the identified pathogens. We did not reveal any significant therapeutic impact of blood cultures in the management of pyelonephritis, when BC and UC are performed before any antimicrobials treatment.

  6. Laboratory Studies of Phosphine Chemistry Relevant to the Jovian and Saturnian Atmospheres

    Liu, Yingdi; Matsiev, Daniel; Robertson, Robert; White, Jason


    The photochemistry of phosphine (PH3) in the tropospheres of Saturn and Jupiter is initiated by ultraviolet (UV) radiation and then follows a cascade of chemical reactions that result in P-H hydrides as well as the condensed chromophore red phosphorus (P4). A key intermediate in this pathway is diphosphine (P2H4). The rate constants for the photodissociation of phosphine into initial phosphino radicals and consequently into formation of diphosphine are currently unavailable, limiting their applicability to observational measurements. The condensation of diphosphine to ice in the cold tropospheres is also poorly understood due to the difficulties in synthesizing, handling, and analyzing the compound.Our presentation will describe two experiments at SRI International to produce rate constants for the photochemistry initiated by UV light interacting with phosphine and diphosphine and properties related to the condensed phases of these species. One study seeks to produce property values for application in photochemical and cloud/haze models. Specifically, we extend the measured vapor pressure curve for diphosphine to temperatures relevant to temperatures of Saturn and Jupiter. A sophisticated vapor pressure cell has been constructed and tested and is coupled to a Fourier transform infrared (FTIR) and mass spectrometer for high-fidelity species diagnostics. A companion study investigates phosphine photochemistry to measure the rate constants of key intermediate species related to the loss of PH3 and the formation of P2H4. The experiments employ laser photolysis at 193 nm followed by time-resolved mid-IR laser-based species detection of reactants, and the products provide basic chemical kinetic data useful for interpreting phosphine photochemistry in planetary atmospheres.These two studies are intended to supply basic physical measurements to aid in the interpretation of outer planet atmospheric observations. For both studies, we will present our latest laboratory

  7. Inner detached frequency response curves: an experimental study

    Gatti, Gianluca; Brennan, Michael J.


    Certain nonlinear vibrating systems have frequency response curves (FRCs), in which isolated detached curves exist inside the main continuous FRC. The behavior of these systems has hitherto been studied analytically and numerically, but to the authors' knowledge, there is no record of an inner detached FRC being detected experimentally. These curves may be hidden by numerical or experimental analysis, particularly when a system is subject to swept or stepped-sine excitation. Their existence may thus lead to unexpected dramatic changes in the amplitude of the system response. This paper presents an experimental study that involves the design, construction and testing of a specific system that has an isolated detached FRC inside the main continuous FRC. The experimental design of the test rig is supported by multibody dynamic simulations, and in the experimental tests the existence of a detached FRC was verified.

  8. [Study on effect of spine surgery on gastric function and its efficacy of relevant treatments].

    Lin, X; Wu, J; Du, J


    To study the effect of spine surgery (SpS) on gastric function and the efficacy of relevant treatments. Sixty patients in the spine surgery group, 20 patients in the extremity surgery (ES) group and 20 healthy subjects in the control group were observed. Electrogastrography (EGG) was used to observe gastroelectric activity before and after operation. Twenty patients among the SpS group were examined with barium meal under actinoscopy to observe the gastric peristaltic waves before and after operation. The SpS group was randomly subdivided into 3 groups, and treated by Xiangsha Yangwei pill (XSYW), moxibustion and motilium respectively. At the same time, the EGG of various groups was observed and the change of preoperative and postoperative EGG were compared. The gastroelectric rhythm of SpS group was remarkably abnormal, both frequency and amplitude of EGG were significantly different from the other two groups (P 0.05). SpS could change the gastroelectric rhythm to cause the gastric functional disorder and induce gastroparesis, EGG can get satisfactory results in the diagnosis of these illnesses. XSYW, moxibustion and motilium all have significant effects on the gastric function after SpS.

  9. Suicide in the Greek penal system and the problem of various limitations in relevant studies.

    Themeli, Olga


    Suicides in prison are not merely self-destructive acts or a "cry for help." They reflect the inherent need for freedom and the repercussions of imprisonment. SPACE statistics on suicides in prison reveal a rate above 10 per 10,000 in 10 European countries, 4 of which have a rate above 20. Greek data do not appear in all SPACE statistics. This fact has stimulated the present paper. Unpublished data obtained from the Greek Ministry of Justice reveal that Greece belongs to the group of countries with a rate below 10 in 1995 (the year of SPACE statistics). However, the suicide rates fluctuated widely in Greece from a low rate of 3.2 per 10,000 prisoners (convicted, on remand, or hospitalized) in 1982 to the incredibly high rate of nearly 40 in the year 1979 (11 suicides, 10 of which occurred in prison hospitals). A review of the literature indicates that various limitations mentioned in relevant studies lie in the unreliability of data (doubts about the validity of official statistics, missing data in archives, missing files on the victims, suicide in juvenile institutions not always recorded separately, etc.). The research emphasizes the importance of improving suicide statistics (recording, clearing up the incidents of deaths that are recorded without specification of cause, etc.) in order to plan and enforce suicide prevention and intervention strategies that seem to "work" in a particular milieu and are not debatable (e.g., the use of "suicide proof" cells).

  10. Teaching Inductive Reasoning: Some Theory and Three Experimental Studies.

    Klauer, Karl Josef


    Three studies involving 174 elementary school students supported the hypothesis that training in an inductive strategy would enhance performance on tests measuring fluid intelligence, support learning school-relevant declarative knowledge, and improve problem solving. Implications for teaching and testing are discussed. (SLD)

  11. Building a clinically relevant cognitive task: case study of the AX paradigm.

    MacDonald, Angus W


    Tasks developed for basic cognitive neuroscience are often ill suited for experimental psychopathology. The development of the expectancy variant of AX continuous performance task to test theories about context processing in schizophrenia is used as an illustration of how this has been done in one research program. Four design principles are recommended: tasks should (1) have a foundation in existing literature and therefore stay as close as possible to an existing task; (2) be simple, which is frequently accomplished by paring down a task to evaluate the function of interest; (3) probe a mechanism of interest, with conditions that selectively manipulate this mechanism; and (4) have the potential to distinguish a specific deficit on the mechanism of interest from a generalized impairment. Data from a number of studies support several aspects of context-processing theory; however unpredicted results have also been reported. The development of the expectancy AX paradigm continues, and future developments that may enhance its usefulness are also described.


    Linda J. COLLINS


    Full Text Available Online professional development (oPD for teachers should focus on designing web-based learning opportunities that help practicing educators solve the tough problems of practice when working in their schools. Technology, pedagogy, and content knowledge can be integrated in the design of online professional development modules to enhance task relevance for maximum learning and transformation. The purpose of this study was to learn which tasks in an online professional development module were ranked by in-service educators as relevant to their work with English language learners (ELLs. Using Q methodology, the researcher asked participants to rank the relevancy of 36 online tasks from an online professional development module designed and developed at an American university. Participants used a -5 to 5 forced distribution to rank online activities from “Least relevant to my work with ELLs” to “Most relevant to my work with ELLs” followed by a semi-structured interview to explain their decisions. After data analysis, two factors emerged, indicating that participants’ perceptions on task relevance differed by professional roles and educational settings. The participants also favored didactic online tasks over interactive tasks. The findings from the oPD participants’ responses have the potential to serve as the basis for future online professional development design and for planning other relevant activities to be applied to the e-learning environment.


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    3 Department of Physics, Arts and Science Faculty, Dumlupınar University, Kütahya, Turkey. 4 Department ... been studied experimentally and theoretically using nuclear magnetic resonance (NMR) spectroscopy. 1H, 13C, ... INTRODUCTION.

  14. The relevance and role of homestays in medical education: a scoping study.

    Hughes, Bonnie Olivia; Moshabela, Mosa; Owen, Jenni; Gaede, Bernhard


    The community-based medical education curriculum is growing in popularity as a strategy to bring universal health coverage to underserved communities by providing medical students with hands-on training in primary health care. Accommodation and immersion of medical students within the community will become increasingly important to the success of community-based curricula. In the context of tourism, homestays, where local families host guests, have shown to provide an immersive accommodation experience. By exploring homestays in the educational context, this scoping study investigates their role in providing an immersive pedagogical experience for medical students. A scoping review was performed using the online databases ScienceDirect and the Duke University Library Database, which searches Academic Search Complete, JSTOR, LexisNexis Academic, Web of Science, Proquest, PubMed and WorldCat. Using the inclusion term 'homestays' and excluding the term 'tourism', 181 results were returned. AClose assessment using inclusion criteria narrowed this to 14 relevant articles. There is very little published research specific to the experience of medical students in community homestays, indicating a gap in the literature. However, the existing educational outcomes suggest homestays may have the potential to serve a significant role in medical education, especially as a component of decentralised or community-based programmes. The literature reveals that educational homestays influence language learning, cultural immersion, and the development of professional skills for health science careers. These outcomes relate to the level of engagement between students and hosts, including the catalytic role of community liaisons. Homestays offer a unique depth of experience that has the potential to enrich the education of participating students, and require further research, particularly in the context of distributed and decentralised training platforms for medical and health sciences

  15. Experimental Study on the Langlee Wave Energy Converter

    Lavelle, John; Kofoed, Jens Peter

    This report concerns the experimental study of the 1:20 scale model of the Langlee Wave Energy Converter (WEC) carried out at Aalborg University’s wave basin during the summer of 2010.......This report concerns the experimental study of the 1:20 scale model of the Langlee Wave Energy Converter (WEC) carried out at Aalborg University’s wave basin during the summer of 2010....

  16. Elaboration of a guide including relevant project and logistic information: a case study

    Costa, Tchaikowisky M. [Faculdade de Tecnologia e Ciencias (FTC), Itabuna, BA (Brazil); Bresci, Claudio T.; Franca, Carlos M.M. [PETROBRAS, Rio de Janeiro, RJ (Brazil)


    For every mobilization of a new enterprise it is necessary to quickly obtain the greatest amount of relative information in regards to location and availability of infra-structure, logistics, and work site amenities. Among this information are reports elaborated for management of the enterprise, (organizational chart, work schedule, objectives, contacts, etc.) as well as geographic anomalies, social-economic and culture of the area to be developed such as territorial extension, land aspects, local population, roads and amenities (fuel stations ,restaurants and hotels), infra-structure of the cities (health, education, entertainment, housing, transport, etc.) and logistically the distance between cities the estimated travel time, ROW access maps and notable points, among other relevant information. With the idea of making this information available for everyone involved in the enterprise, it was elaborated for GASCAC Spread 2A a rapid guide containing all the information mentioned above and made it available for all the vehicles used to transport employees and visitors to the spread. With this, everyone quickly received the majority of information necessary in one place, in a practical, quick, and precise manner, since the information is always used and controlled by the same person. This study includes the model used in the gas pipeline GASCAC Spread 2A project and the methodology used to draft and update the information. Besides the above, a file in the GIS format was prepared containing all necessary planning, execution and tracking information for enterprise activities, from social communication to the execution of the works previously mentioned. Part of the GIS file information was uploaded to Google Earth so as to disclose the information to a greater group of people, bearing in mind that this program is free of charge and easy to use. (author)

  17. Environmental relevance of laboratory-derived kinetic models to predict trace metal bioaccumulation in gammarids: Field experimentation at a large spatial scale (France).

    Urien, N; Lebrun, J D; Fechner, L C; Uher, E; François, A; Quéau, H; Coquery, M; Chaumot, A; Geffard, O


    Kinetic models have become established tools for describing trace metal bioaccumulation in aquatic organisms and offer a promising approach for linking water contamination to trace metal bioaccumulation in biota. Nevertheless, models are based on laboratory-derived kinetic parameters, and the question of their relevance to predict trace metal bioaccumulation in the field is poorly addressed. In the present study, we propose to assess the capacity of kinetic models to predict trace metal bioaccumulation in gammarids in the field at a wide spatial scale. The field validation consisted of measuring dissolved Cd, Cu, Ni and Pb concentrations in the water column at 141 sites in France, running the models with laboratory-derived kinetic parameters, and comparing model predictions and measurements of trace metal concentrations in gammarids caged for 7 days to the same sites. We observed that gammarids poorly accumulated Cu showing the limited relevance of that species to monitor Cu contamination. Therefore, Cu was not considered for model predictions. In contrast, gammarids significantly accumulated Pb, Cd, and Ni over a wide range of exposure concentrations. These results highlight the relevance of using gammarids for active biomonitoring to detect spatial trends of bioavailable Pb, Cd, and Ni contamination in freshwaters. The best agreements between model predictions and field measurements were observed for Cd with 71% of good estimations (i.e. field measurements were predicted within a factor of two), which highlighted the potential for kinetic models to link Cd contamination to bioaccumulation in the field. The poorest agreements were observed for Ni and Pb (39% and 48% of good estimations, respectively). However, models developed for Ni, Pb, and to a lesser extent for Cd, globally underestimated bioaccumulation in caged gammarids. These results showed that the link between trace metal concentration in water and in biota remains complex, and underlined the limits of

  18. Social Studies Pedagogy for Latino/a Newcomer Youth: Toward a Theory of Culturally and Linguistically Relevant Citizenship Education

    Jaffee, Ashley Taylor


    This study examines how teachers in 4 urban newcomer high schools conceptualized and implemented social studies education for Latino/a newcomer youth through an emerging framework of culturally and linguistically relevant citizenship education. Through a multi-site, collective case study design, the perspectives and decision making of social…

  19. Social Studies Pedagogy for Latino/a Newcomer Youth: Toward a Theory of Culturally and Linguistically Relevant Citizenship Education

    Jaffee, Ashley Taylor


    This study examines how teachers in 4 urban newcomer high schools conceptualized and implemented social studies education for Latino/a newcomer youth through an emerging framework of culturally and linguistically relevant citizenship education. Through a multi-site, collective case study design, the perspectives and decision making of social…

  20. Establishment of HK-2 Cells as a Relevant Model to Study Tenofovir-Induced Cytotoxicity

    Rachel A. Murphy


    Full Text Available Tenofovir (TFV is an antiviral drug approved for treating Human Immunodeficiency Virus (HIV and Hepatitis B. TFV is administered orally as the prodrug tenofovir disoproxil fumarate (TDF which then is deesterified to the active drug TFV. TFV induces nephrotoxicity characterized by renal failure and Fanconi Syndrome. The mechanism of this toxicity remains unknown due to limited experimental models. This study investigated the cellular mechanism of cytotoxicity using a human renal proximal tubular epithelial cell line (HK-2. HK-2 cells were grown for 48 h followed by 24 to 72 h exposure to 0–28.8 μM TFV or vehicle, phosphate buffered saline (PBS. MTT (MTT, 3-(4,5-dimethylthiazol-2-yl-2,5-Diphenyltetrazolium Bromide and Trypan blue indicated that TFV diminished cell viability at 24–72 h. TFV decreased ATP levels at 72 h when compared to vehicle, reflecting mitochondrial dysfunction. TFV increased the oxidative stress biomarkers of protein carbonylation and 4-hydroxynonenol (4-HNE adduct formation. Tumor necrosis factor alpha (TNFα was released into the media following exposure to 14.5 and 28.8 μM TFV. Caspase 3 and 9 cleavage was induced by TFV compared to vehicle at 72 h. These studies show that HK-2 cells are a sensitive model for TFV cytotoxicity and suggest that mitochondrial stress and apoptosis occur in HK-2 cells treated with TFV.

  1. $^{206}$ Po sources for production and release studies relevant for high power spallation targets

    The knowledge of the evaporation behaviour of Po is of essential importance for several scientific and technological applications, like accelerator driven systems (ADS) or the LIEBE project at CERN-ISOLDE. Fundamental investigations on the experimental conditions for the formation of volatile Po species as well as on the chemical composition of the volatile compounds are necessary for a safe operation of such facilities. $^{206}$Po, a mainly $\\gamma$- ray-emitting Po isotope with a half-life of 8.8 d, is best suited for model studies, due to the lower radiation hazard compared to the longer-lived $\\alpha$-emitting isotopes $^{208-210}$Po as well as the easy-to-measure $\\gamma$-ray emission. We propose the production of $^{206}$Po samples in several matrices via the implantation of its precursor $^{210}$Fr into selected metal foils at CERN-ISOLDE. Using these samples, experiments will be carried out at PSI studying the volatilization of Po from different matrices under varying chemical conditions.

  2. Non-spatial pre-training in the water maze as a clinically relevant model for evaluating learning and memory in experimental TBI.

    Wagner, Amy K; Brayer, Samuel W; Hurwitz, Max; Niyonkuru, Christian; Zou, Huichao; Failla, Michelle; Arenth, Patricia; Manole, Mioara D; Skidmore, Elizabeth; Thiels, Edda


    Explicit and implicit learning and memory networks exist where each network can facilitate or inhibit cognition. Clinical evidence suggests that implicit networks are relatively preserved after traumatic brain injury (TBI). Non-spatial pre-training (NSPT) in the Morris Water Maze (MWM) provides the necessary behavioral components to complete the task, while limiting the formation of spatial maps. Our study utilized NSPT in the MWM to assess implicit and explicit learning and memory system deficits in the controlled cortical impact (CCI) model of TBI. 76 adult male Sprague-Dawley rats were divided: CCI vs. sham surgery, NSPT vs. No-NSPT, and cued vs. non-cued groups. NSPT occurred for 4d prior to surgery (dynamic hidden platform location, extra-maze cues covered, static pool entry point). Acquisition (d14-18), Probe/Visible Platform (d19), and Reversal (d20-21) trials were conducted with or without extra-maze cues. Novel time allocation and search strategy selection metrics were utilized. Results indicated implicit and explicit learning/memory networks are distinguishable in the MWM. In the cued condition, NSPT reduced thigmotaxis, improved place learning, and largely eliminated the apparent injury-induced deficits typically observed between untrained CCI and sham rats. However, among NSPT groups, incorporation of cues into search strategy selection for CCI rats was relatively impaired compared to shams. Non-cued condition performance showed sham/NSPT and CCI/NSPT rats perform similarly, suggesting implicit memory networks are largely intact 2weeks after CCI. Place learning differences between CCI/NSPT and sham/NSPT rats more accurately reflect spatial deficits in our CCI model compared to untrained controls. These data suggest NSPT as a clinically relevant construct for evaluating potential neurorestorative and neuroprotective therapies. These findings also support development of non-spatial cognitive training paradigms for evaluating rehabilitation relevant

  3. Experimental study on the characteristics of semiconductor opening switch

    Su Jian Cang; Ding Yong Zhong; Song Zhi Min; Ding Zhen Jie; Liu Guo Zhi


    An experimental set-up is developed to measure the characteristics of semiconductor opening switch (SOS). The parameters, such as interruption impedance, current int eruption time, voltage gain, pulse duration and energy transfer efficiency, are studied experimentally. The experimental results show that forward pumping time and reverse pumping time are important parameters for semiconductor opening switches. The influences of forward pumping time and reverse pumping time on interruption time, voltage gain, and energy transfer efficiency are obtained. In the interruption process, the impedance variation is divided into three phases: that is rapid increasing phase, slow change phase and completely interruption phase

  4. Matrix-Isolation Spectroscopy and Computational Studies of Reactive Organic Molecules of Relevance to Interstellar Space

    Kopff, Laura A.; Kreifels, Terese A.; Schaffer, Christopher J.; Haenni, Benjamin C.; Esselman, Brian J.; McMahon, Robert J.


    Matrix isolation, the process of trapping a molecule in an inert gas at low temperature, provides a means for studying highly reactive intermediates, such as carbenes or radicals. Reactive species can be characterized by IR, UV-vis and/or EPR spectroscopy. Comparison of experimental and computed spectral data, as well as chemical reactivity, is used for structural assignment. Highly-unsaturated carbon chains are well known compounds in the interstellar medium (ISM). Detection of these molecules relies mostly on radioastronomy, making the detection of the linear HC2nH series difficult. The electronic structure changes from even carbon chain lengths (HC2nH) to odd chain lengths (HC2n+1H), changing from closed shell to open shell species. The odd series further alternate from a diradical character (HC3H) to a localized carbene (HC5H). This poster will present the synthesis and spectroscopy of the HC3H and HC7H species and derivatives. The study of arylcarbenes is vital to understanding the chemistry of carbon-rich environments, such as discharges, interstellar clouds, and circumstellar envelopes. The identification of small, sulfur containing molecules, and the identification of aromatics in the ISM make future thiophene and benzothiophene detections a real possibility. Studies on 2- and 3- diazomethyl substituted benzothiophenes are underway to assess their photochemical reactivity and potential for forming benzothiophene carbenes. Macrocylic polyynes are proposed to be involved in carbon condensation via the ring coalescence and annealing model to produce graphitic sheets or fullerenes. To simplify a complex system we are computationally studying the series of ethynyl-substituted cyclobutadienes and their possible involvement in the build-up of larger carbon containing molecules in the ISM.

  5. Systematically Identifying Relevant Research: Case Study on Child Protection Social Workers' Resilience

    McFadden, Paula; Taylor, Brian J.; Campbell, Anne; McQuilkin, Janice


    Context: The development of a consolidated knowledge base for social work requires rigorous approaches to identifying relevant research. Method: The quality of 10 databases and a web search engine were appraised by systematically searching for research articles on resilience and burnout in child protection social workers. Results: Applied Social…

  6. Systematically Identifying Relevant Research: Case Study on Child Protection Social Workers' Resilience

    McFadden, Paula; Taylor, Brian J.; Campbell, Anne; McQuilkin, Janice


    Context: The development of a consolidated knowledge base for social work requires rigorous approaches to identifying relevant research. Method: The quality of 10 databases and a web search engine were appraised by systematically searching for research articles on resilience and burnout in child protection social workers. Results: Applied Social…

  7. Clinically relevant QTc prolongation due to overridden drug-drug interaction alerts: A retrospective cohort study

    I.H. van der Sijs (Heleen); R. Kowlesar (Ravi); A.P.J. Klootwijk (Peter); S.P. Nelwan (Stefan); A.G. Vulto (Arnold); T. van Gelder (Teun)


    textabstractAIMS: To investigate whether, in patients in whom drug-drug interaction (DDI) alerts on QTc prolongation were overridden, the physician had requested an electrocardiogram (ECG), and if these ECGs showed clinically relevant QTc prolongation. METHODS: For all patients with overridden DDI a

  8. A comprehensive experimental and modeling study of isobutene oxidation

    Zhou, Chong-Wen


    Isobutene is an important intermediate in the pyrolysis and oxidation of higher-order branched alkanes, and it is also a component of commercial gasolines. To better understand its combustion characteristics, a series of ignition delay time (IDT) and laminar flame speed (LFS) measurements have been performed. In addition, flow reactor speciation data recorded for the pyrolysis and oxidation of isobutene is also reported. Predictions of an updated kinetic model described herein are compared with each of these data sets, as well as with existing jet-stirred reactor (JSR) species measurements. IDTs of isobutene oxidation were measured in four different shock tubes and in two rapid compression machines (RCMs) under conditions of relevance to practical combustors. The combination of shock tube and RCM data greatly expands the range of available validation data for isobutene oxidation models to pressures of 50 atm and temperatures in the range 666–1715 K. Isobutene flame speeds were measured experimentally at 1 atm and at unburned gas temperatures of 298–398 K over a wide range of equivalence ratios. For the flame speed results, there was good agreement between different facilities and the current model in the fuel-rich region. Ab initio chemical kinetics calculations were carried out to calculate rate constants for important reactions such as H-atom abstraction by hydroxyl and hydroperoxyl radicals and the decomposition of 2-methylallyl radicals. A comprehensive chemical kinetic mechanism has been developed to describe the combustion of isobutene and is validated by comparison to the presently considered experimental measurements. Important reactions, highlighted via flux and sensitivity analyses, include: (a) hydrogen atom abstraction from isobutene by hydroxyl and hydroperoxyl radicals, and molecular oxygen; (b) radical–radical recombination reactions, including 2-methylallyl radical self-recombination, the recombination of 2-methylallyl radicals with

  9. Adolescents' prosocial responses to ostracism: an experimental study.

    Coyne, Sarah M; Gundersen, Nicola; Nelson, David A; Stockdale, Laura


    Ostracism can lead to strong behavioral responses, including diminished prosocial behavior. To date, experimental research examining this effect has only been conducted with adults. The current study consisted of 40 adolescents, half of whom were experimentally ostracized using the Cyberball paradigm. Participants' subsequent levels of pronounced prosocial behavior were measured, and personality traits were examined as possible moderators in participant behavioral responses. Results revealed that, compared to controls, ostracized adolescents showed less prosocial behavior, and this was moderated by having an "open" personality.

  10. Student perception of relevance of biology content to everyday life: A study in higher education biology courses

    Himschoot, Agnes Rose

    The purpose of this mixed method case study was to examine the effects of methods of instruction on students' perception of relevance in higher education non-biology majors' courses. Nearly ninety percent of all students in a liberal arts college are required to take a general biology course. It is proposed that for many of those students, this is the last science course they will take for life. General biology courses are suspected of discouraging student interest in biology with large enrollment, didactic instruction, covering a huge amount of content in one semester, and are charged with promoting student disengagement with biology by the end of the course. Previous research has been aimed at increasing student motivation and interest in biology as measured by surveys and test results. Various methods of instruction have been tested and show evidence of improved learning gains. This study focused on students' perception of relevance of biology content to everyday life and the methods of instruction that increase it. A quantitative survey was administered to assess perception of relevance pre and post instruction over three topics typically taught in a general biology course. A second quantitative survey of student experiences during instruction was administered to identify methods of instruction used in the course lecture and lab. While perception of relevance dropped in the study, qualitative focus groups provided insight into the surprising results by identifying topics that are more relevant than the ones chosen for the study, conveying the affects of the instructor's personal and instructional skills on student engagement, explanation of how active engagement during instruction promotes understanding of relevance, the roll of laboratory in promoting students' understanding of relevance as well as identifying external factors that affect student engagement. The study also investigated the extent to which gender affected changes in students' perception of

  11. Reactivity, characterization, equilibrium thermodynamics and hetero-bimetallic studies of tridentate and tetradentate complexes relevant to syngas catalysis

    Imler, Gregory H.

    The unifying objective of this work is the study of model systems that will assist in the development of new metal catalysts capable of converting carbon monoxide and hydrogen (syngas) into organic oxygenates at mild temperature and pressure. The selective catalytic transformation of carbon monoxide and hydrogen to liquid fuels and chemical feedstocks represents a major "Grand Challenge" of catalysis science. A core objective is the study of a macrocycle that is related to a porphyrin ligand in order to circumvent some of the disadvantages of utilizing porphyrins in catalysis. The rhodium complex of the macrocycle dibenzotetramethylaza[14]annulene ([(tmtaa)Rh]2]) was reacted with a series of small molecules relevant to CO reduction and hydrogenation. Several complexes were formed that demonstrated the ability to partially reduce and hydrogenate carbon monoxide, including the dirhodium ketone (Rh-C(O)-Rh) and an example of a thermodynamically favorable metal formyl complex ((tmtaa)Rh-C(O)H). An important feature of this work is the measurement of thermodynamic data to provide experimental benchmarks for obtaining key species in CO reduction and hydrogenation. A thorough study of the (tmtaa)Rh system will help in identifying structural features that assist or hinder CO hydrogenation. All reactions are monitored by 1H NMR which permits determination of solution thermodynamics from equilibrium constants obtained by NMR peak integrations. DFT calculations have supplemented experimental results by providing estimates to compare with the experimentally determined thermodynamic data. These computations also provide insight into the structures and thermodynamics of species that cannot be observed directly such as short lived intermediates and thermodynamically unfavorable products. Heterobimetallic complexes of (tmtaa)Rh• with a second metal radical have been utilized to attempt to convert CO to organic products. Reactivity with CO and H2 has been accomplished, with most

  12. Experimental systems for studying Plasmodium/HIV coinfection.

    Frischknecht, Friedrich; Fackler, Oliver T


    Coinfections with Human Immunodeficiency Virus (HIV) and Plasmodium, the causative agents of AIDS and malaria, respectively, are frequent and their comorbidity especially in sub-Saharan Africa is high. While clinical studies suggest an influence of the two pathogens on the outcome of the respective infections, experimental studies on the molecular and immunological impact of coinfections are rare. This reflects the limited availability of suitable model systems that reproduce key properties of both pathologies. Here, we discuss key aspects of coinfection with a focus on currently established experimental systems, their limitations for coinfection studies and potential strategies for their improvement.

  13. Research designs for experimental single-case studies

    Ralf Spieß


    Full Text Available This overview describes the most important designs for single case experimental studies, which are ABAB-design, multiple baseline design, alternating treatments design and changing criterion design. The logic of experimental control in single case studies is explained and it is described, how these different designs are able to provide internal validity and enable causal interpretations of intervention outcome. An important precondition of valid interpretation is objective and reliable data assessment. Data evaluation by visual inspection is explained and several methods of statistical data analysis are discussed. To establish generability across persons, situations, and settings, the importance of replication studies is highlighted.

  14. Relevant assay to study the adhesion of Plasmodium falciparum-infected erythrocytes to the placental epithelium.

    Philippe Boeuf

    Full Text Available In placental malaria, Plasmodium falciparum-infected erythrocytes adhere to the apical plasma membrane of the placental epithelium, triggering an impairment of placental function detrimental to the fetus. The design of anti-adhesion intervention strategies requires a detailed understanding of the mechanisms involved. However, most adhesion assays lack in vivo relevance and are hardly quantitative. Here, we describe a flow cytometry-based adhesion assay that is fully relevant by using apical epithelial plasma membrane vesicles as the adhesion matrix, and being applicable to infected erythrocytes directly isolated from patients. Adhesion is measured both as the percentage of pathogens bound to epithelial membrane vesicles as well as the mean number of vesicles bound per infected erythrocytes. We show that adhesins alternative to those currently identified could be involved. This demonstrates the power of this assay to advance our understanding of epithelial adhesion of infected erythrocytes and in the design of intervention strategies.

  15. Theoretical and experimental study of the characteristics of short wind waves

    王伟; 沈正


    By virtue of a novel experimental method, Phillips’ blockage theory was verified, while some of the experimental phenomena could not be well explained by Phillips’ theory. Deriving from the dynamic equations, the results obtained expound the experimental phenomena satisfactorily. The relevant conclusions have significant and great pushing effects on ocean remote sensing techniques and potential value to ocean remote sensing techniques.

  16. Co-evolution of conventions and networks : an experimental study

    Corten, R.; Buskens, V.W.


    We study the emergence of conventions in dynamic networks experimentally. Conventions are modeled in terms of coordination games in which actors can choose both their behavior and their interaction partners. We study how macro-level outcomes of the process in terms of Pareto-efficiency and heterogen

  17. Experimental Studies on Turbulence Kinetic Energy in Confined Vortex Flows

    L.Yan; G.H.Vatistas; 等


    Turbulence kinetic energies in confined vortex flows have been studied.The studies were based on the experiments performed in a vortex chamber,In the experiments,a Laser Doppler Anemometry(LDA) was used to perform flow measurements inside the vortex chamber,which provided the data for the kinetic energy analysis.The studies concentrated on the influences of the contraction ratio and the inlet air flow rate on the kinetic energy,and analyzed the characteristics of the kinetic energy in the confined vortex flows,including the distributions of the tangential component,radial component and total turbulence kinetic energy,In the paper,both the experimental techniques and the experimental results were presented.Based on a similarity analyis and the experimental data,an empirical scaling formula was proposed so that the tangential component of the turbulence kinetic energy was dependent only on the parameter of the contraction ratio.

  18. The reaction between iodine and organic coatings under severe PWR accident conditions. An experimental parameter study

    Hellmann, S.; Funke, F.; Greger, G.U.; Bleier, A.; Morell, W. [Siemens AG, Power Generation Group, Erlangen (Germany)


    An extensive experimental parameter study was performed on the deposition and on the resuspension kinetics in the reaction system iodine/organically coated surfaces. Both reactions in the gas phase and in the liquid phase were investigated and kinetic rate constants suitable for modelling were derived. Previous experimental studies on the reaction of iodine with organic coated surfaces were mostly limited to temperatures below 100{sup o}C. Thus, this parameter study aims at filling a gap and providing kinetic data on heterogeneous reactions with organic surfaces in the accident-relevant temperature range of 100-160{sup o}C. Two types of laboratory experiments carried out at Siemens/KWU using coatings representative for German power plants (epoxy-tape paint), namely gas phase tests and liquid phase tests. (author) 6 figs., 6 tabs., 5 refs.

  19. Evaluating experimental molecular physics studies of radiation damage in DNA*

    Śmiałek, Małgorzata A.


    The field of Atomic and Molecular Physics (AMP) is a mature field exploring the spectroscopy, excitation, ionisation of atoms and molecules in all three phases. Understanding of the spectroscopy and collisional dynamics of AMP has been fundamental to the development and application of quantum mechanics and is applied across a broad range of disparate disciplines including atmospheric sciences, astrochemistry, combustion and environmental science, and in central to core technologies such as semiconductor fabrications, nanotechnology and plasma processing. In recent years the molecular physics also started significantly contributing to the area of the radiation damage at molecular level and thus cancer therapy improvement through both experimental and theoretical advances, developing new damage measurement and analysis techniques. It is therefore worth to summarise and highlight the most prominent findings from the AMP community that contribute towards better understanding of the fundamental processes in biologically-relevant systems as well as to comment on the experimental challenges that were met for more complex investigation targets. Contribution to the Topical Issue "Low-Energy Interactions related to Atmospheric and Extreme Conditions", edited by S. Ptasinska, M. Smialek-Telega, A. Milosavljevic, B. Sivaraman.

  20. Low-temperature Kinetic Studies of OH Radical Reactions Relevant to Planetary Atmospheres

    Townsend, T. M.; Antiñolo, M.; Ballesteros, B.; Jimenez, E.; Canosa, A.


    In the solar system, the temperature (T) of the atmosphere of giant planets or their satellites is only several tens of Kelvin (K). The temperature of the tropopause of Titan (satellite of Saturn) and the surface of Mars is 70 K and 210 K, respectively. In the Earth's atmosphere, T decreases from 298 K (surface) to 210 K close to the T-inversion region (tropopause). The principal oxidants in the Earth's lower atmosphere are ozone, the hydroxyl (OH) radical and hydrogen peroxide. A number of critical atmospheric chemical problems depend on the Earth's oxidising capacity, which is essentially the global burden of these oxidants. In the interstellar clouds and circumstellar envelopes, OH radicals have also been detected. As the chemistry of atmospheres is highly influenced by temperature, the knowledge of the T-dependence of the rate coefficients for OH-reactions (k) is the key to understanding the underlying molecular mechanisms. In general, these reactions take place on a short temporal scale. Therefore, a detection technique with high temporal resolution is required. Measurements of k at low temperatures can be achieved by maintaining a thermalised environment using either cryogenic cooling (T>200 K) or supersonic gas expansion with a Laval nozzle (several tens of K). The pulsed laser photolysis technique coupled with laser induced fluorescence detection has been widely used in our laboratory to determine the rate coefficients of OH-reactions with different volatile organic compounds, such as alcohols (1), saturated and unsaturated aliphatic aldehydes (2), linear ketones (3), as a function of temperature (260 350 K). An experimental system based on the CRESU (Cinetique de Reaction en Ecoulement Supersonique Uniforme or Reaction Kinetics in a Uniform Supersonic Flow) technique is currently under construction. This technique will allow the performance of kinetic studies of OH-reactions of astrophysical interest at temperatures lower than 200 K.

  1. Experimental pretesting of public health campaigns: a case study.

    Whittingham, Jill; Ruiter, Robert A C; Zimbile, Filippo; Kok, Gerjo


    The aim of the present study is to demonstrate the merits of evaluating new public health campaign materials in the developmental phase using an experimental design. This is referred to as experimental pretesting. In practice, most new materials are tested only after they have been distributed using nonexperimental or quasiexperimental designs. In cases where materials are pretested prior to distribution, pretesting is usually done using qualitative research methods such as focus groups. Although these methods are useful, they cannot reliably predict the effectiveness of new campaign materials in a developmental phase. Therefore, we suggest when pretesting new materials, not only qualitative research methods but also experimental research methods must be used. The present study discusses an experimental pretest study of new campaign materials intended for distribution in a national sexually transmitted infection (STI) AIDS prevention campaign in the Netherlands. The campaign material tested was the storyline of a planned television commercial on safe sex. A storyboard that consisted of drawings and text was presented to members of the target population, namely, students between the ages of 14 and 16 enrolled in vocational schools. Results showed positive effects on targeted determinants of safe sexual behavior. The advantages, practical implications, and limitations of experimental pretesting are discussed.

  2. Analytical and Experimental Study of Residual Stresses in CFRP

    Chia-Chin Chiang


    Full Text Available Fiber Bragg Grating sensors (FBGs have been utilized in various engineering and photoelectric fields because of their good environment tolerance. In this research, residual stresses of carbon fiber reinforced polymer composites (CFRP were studied using both experimental and analytical approach. The FBGs were embedded inside middle layers of CFRP to study the formation of residual stress during curing process. Finite element analysis was performed using ABAQUS software to simulate the CFRP curing process. Both experimental and simulation results showed that the residual stress appeared during cooling process and the residual stresses could be released when the CFRP was machined to a different shape.

  3. Experimental study of buoyancy driven natural ventilation through horizontal openings

    Heiselberg, Per; Li, Zhigang


    An experimental study of buoyancy driven natural ventilation through single-sided horizontal openings was performed in a full-scale laboratory test rig. Measurements were made for opening ratios L/D range from 0.027 to 4.455, where L and D are the length and the diameter of the opening, respectiv......An experimental study of buoyancy driven natural ventilation through single-sided horizontal openings was performed in a full-scale laboratory test rig. Measurements were made for opening ratios L/D range from 0.027 to 4.455, where L and D are the length and the diameter of the opening...

  4. Diffusion in liquids a theoretical and experimental study

    Tyrrell, H J V


    Diffusion in Liquids: A Theoretical and Experimental Study aims to discuss the principles, applications, and advances in the field of diffusion, thermal diffusion, and thermal conduction in liquid systems. The book covers topics such as the principles of non-equilibrium thermodynamics; diffusion in binary and multicompetent systems; and experimental methods of studying diffusion processes in liquids. Also covered in the book are topics such as the theoretical interpretations of diffusion coefficients; hydrodynamic and kinetic theories; and diffusion in electrolyte systems. The text is recommen

  5. Experimental study of interband and intraband crosstalk in WDM networks


    The impacts of interband and intraband crosstalk are studied and compared experimentally. Results show that interband crosstalk can be removed with narrow-band filters and has no influence on signal. Intraband crosstalk will result in signal eye diagram close and BER increasing. When the polarization states of signal and crosstalk align, intraband crosstalk seriously decreases signal quality. But when they misalign, it has little influence. Coherent and incoherent crosstalk are studied experimentally. Results show that coherent crosstalk is less harmful to system performance than incoherent crosstalk.

  6. An experimental and modeling study of diethyl carbonate oxidation

    Nakamura, Hisashi


    Diethyl carbonate (DEC) is an attractive biofuel that can be used to displace petroleum-derived diesel fuel, thereby reducing CO2 and particulate emissions from diesel engines. A better understanding of DEC combustion characteristics is needed to facilitate its use in internal combustion engines. Toward this goal, ignition delay times for DEC were measured at conditions relevant to internal combustion engines using a rapid compression machine (RCM) and a shock tube. The experimental conditions investigated covered a wide range of temperatures (660-1300K), a pressure of 30bar, and equivalence ratios of 0.5, 1.0 and 2.0 in air. To provide further understanding of the intermediates formed in DEC oxidation, species concentrations were measured in a jet-stirred reactor at 10atm over a temperature range of 500-1200K and at equivalence ratios of 0.5, 1.0 and 2.0. These experimental measurements were used to aid the development and validation of a chemical kinetic model for DEC.The experimental results for ignition in the RCM showed near negative temperature coefficient (NTC) behavior. Six-membered alkylperoxy radical (RO˙2) isomerizations are conventionally thought to initiate low-temperature branching reactions responsible for NTC behavior, but DEC has no such possible 6- and 7-membered ring isomerizations. However, its molecular structure allows for 5-, 8- and 9-membered ring RO˙2 isomerizations. To provide accurate rate constants for these ring structures, ab initio computations for RO˙2⇌Q˙OOH isomerization reactions were performed. These new RO˙2 isomerization rate constants have been implemented in a chemical kinetic model for DEC oxidation. The model simulations have been compared with ignition delay times measured in the RCM near the NTC region. Results of the simulation were also compared with experimental results for ignition in the high-temperature region and for species concentrations in the jet-stirred reactor. Chemical kinetic insights into the

  7. Enhanced Field Emission Studies on Niobium Surfaces Relevant to High Field Superconducting Radio-Frequency Devices

    Wang, Tong [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States)


    address concerns on the effect of natural air drying process on EFE, a comparative study was conducted on Nb and the results showed insignificant difference under the experimental conditions. Nb thin films deposited on Cu present a possible alternative to bulk Nb in superconducting cavities. The EFE performance of a preliminary energetically deposited Nb thin film sample are presented.

  8. RC Columns Strengthened with Novel CFRP Systems: An Experimental Study

    Annalisa Napoli


    Full Text Available This paper presents an experimental study undertaken to investigate the seismic behavior of full scale square (300 mm × 300 mm reinforced concrete (RC columns strengthened with novel systems employing carbon fiber-reinforced polymers (CFRP wraps. Experimental tests were carried out by subjecting specimens to a constant axial load and a cyclically reversed horizontal force applied in displacement control. Results have allowed for investigating the influence of the used strengthening systems on the specimens’ performance in terms of flexural strength and ductility as well as on the exhibited failure modes. The effectiveness of the studied techniques is also evaluated by comparing the performance of tested specimens with that of companion columns strengthened with alternative CFRP systems investigated in a previous experimental campaign.

  9. Conversion of eugenol to methyleugenol: Computational study and experimental

    Kurniawan, Muhammad Arsyik; Matsjeh, Sabirin; Triono, Sugeng


    This study provides comprehensive benchmark calculations for the computational study and experimental research on conversion of eugenol to methyleugenol with different pathway of the transition state compounds. First-principle calculation (DFT) were used to generate the structure optimization, energies of species. The calculation parameter are used to predict reactant, product and transition state species as guide to predict the experimental development of chemical characterization method including NMR and IR. The calculation showed significant effect of NaOH in formation of transition state in reaction. Experimentally, the step was nucleophilic substitution reaction of eugenolate ion to dimethylsulfate compound, it was obtained methyleugenol compound with purity of 90.73 %, which analyzed by Infrared and H-NMR spectrometer.

  10. The Relevance of Cultural and Media Studies to Theatre and Television in Bali

    Mark Hobart


    Full Text Available AbstractA critical approach to Balinese society presents a starkly different picturefrom the representations that Balinese usually tell themselves, whichare largely myths to disguise a painful reality. Bali no longer belongsto Balinese but to international capital, a process of alienation by whichBalinese energetically commoditize their culture while claiming theopposite. Even the frames of reference for discussing what is happeningare inadequate because they predate the rise of contemporary consumercapitalism and the mass media. That is why critical media and culturalstudies, disciplines designed precisely to address such phenomena, arepotentially so relevant for Indonesian intellectuals.

  11. Cultural Relevance for Rural Community Development in China: A Case Study in Bai, Jingpo and Huyaodai Communities of Yunnan Province

    Cai Kui; Du Juan; Dai Cong; Hu Huabin


    A three-year study over the Bai, Jingpo and Huayaodai communities in Yunnan Province reveals that the community development is significantly influenced in various ways by such cultural factors as the concepts of development; concepts and traditions of inter-community relationships, consumption, marriage and gender; patterns of decision-making and production, resource and income allocation; as well as the role of information dissemination systems, religion and ritual. Based on the analysis over the interactive relevance between each factor and community development, some strategies and methods for dealing with such a cultural relevance in development projects are recommended.

  12. Impact of micropollutants on the life-history traits of the mosquito Aedes aegypti: On the relevance of transgenerational studies.

    Prud'homme, Sophie M; Chaumot, Arnaud; Cassar, Eva; David, Jean-Philippe; Reynaud, Stéphane


    Hazard assessment of chemical contaminants often relies on short term or partial life-cycle ecotoxicological tests, while the impact of low dose throughout the entire life cycle of species across multiple generations has been neglected. This study aimed at identifying the individual and population-level consequences of chronic water contamination by environmental concentrations of three organic micropollutants, ibuprofen, bisphenol A and benzo[a]pyrene, on Aedes aegypti mosquito populations in experimental conditions. Life-history assays spanning the full life-cycle of exposed individuals and their progeny associated with population dynamics modelling evidenced life-history traits alterations in unexposed progenies of individuals chronically exposed to 1 μg/L ibuprofen or 0.6 μg/L benzo[a]pyrene. The progeny of individuals exposed to ibuprofen showed an accelerated development while the progeny of individuals exposed to benzo[a]pyrene showed a developmental acceleration associated with an increase in mortality rate during development. These life-history changes due to pollutants exposure resulted in relatively shallow increase of Ae. aegypti asymptotic population growth rate. Multigenerational exposure for six generations revealed an evolution of population response to ibuprofen and benzo[a]pyrene across generations, leading to a loss of previously identified transgenerational effects and to the emergence of a tolerance to the bioinsecticide Bacillus turingiensis israelensis (Bti). This study shed light on the short and long term impact of environmentally relevant doses of ibuprofen and benzo[a]pyrene on Ae. aegypti life-history traits and insecticide tolerance, raising unprecedented perspectives about the influence of surface water pollution on vector-control strategies. Overall, our approach highlights the importance of considering the entire life cycle of organisms, and the necessity to assess the transgenerational effects of pollutants in ecotoxicological

  13. From clinically relevant outcome measures to quality of life in epilepsy : A time trade-off study

    de Kinderen, Reina J A; Wijnen, Ben F M; van Breukelen, Gerard; Postulart, Debby; Majoie, Marian H J M; Aldenkamp, Albert P; Evers, Silvia M A A


    OBJECTIVES: A proposed method for bridging the gap between clinically relevant epilepsy outcome measures and quality-adjusted life years is to derive utility scores for epilepsy health states. The aim of this study is to develop such a utility-function and to investigate the impact of the epilepsy o

  14. Using Relevant Video Clips from Popular Media to Enhance Learning in Large Introductory Psychology Classes: A Pilot Study

    Rowland-Bryant, Emily; Skinner, Amy L.; Dixon, Lee; Skinner, Christopher H.; Saudargas, Richard


    The purpose of this study was to enhance students' learning by supplementing a multimedia lesson with interesting and relevant video clips (VCs). Undergraduate students watched a target material PowerPoint (tmPP) presentation with voice-over lecture covering the Big Five trait theory of personality. Students were randomly assigned to one of four…

  15. Perspectives of Employees with Intellectual Disabilities on Themes Relevant to Their Job Satisfaction. An Explorative Study Using Photovoice

    Akkerman, Alma; Janssen, Cees G. C.; Kef, Sabina; Meininger, Herman P.


    Background: This study explored the perspectives of people with intellectual disabilities on themes relevant to their job satisfaction in integrated and sheltered employment. Method: The photovoice method was used. Nine participants with moderate to mild intellectual disabilities, working in integrated and sheltered employment, took pictures of…

  16. The Effects of Topic Familiarity, Author Expertise, and Content Relevance on Norwegian Students' Document Selection: A Mixed Methods Study

    McCrudden, Matthew T.; Stenseth, Tonje; Bråten, Ivar; Strømsø, Helge I.


    This mixed methods study investigated the extent to which author expertise and content relevance were salient to secondary Norwegian students (N = 153) when they selected documents that pertained to more familiar and less familiar topics. Quantitative results indicated that author expertise was more salient for the less familiar topic (nuclear…


    S. O. Losenkova


    Full Text Available We have carried out an experimental study of dose-dependent gastroprotective activity of transdermal plaster with ethylmethylhydroxypyridine succinate (mexidol, the purpose of which was the histological study of gastric mucosa, determination of lipid peroxidation (LP in gastric tissue supernatant, weight study of thymus, spleen, and adrenals. Ethylmethylhydroxypyridine succinate has gastroprotective action in transdermal implementation at 20-75 mg/kg dose on the model of 18-hour immobilization of animals which had been starving for 24 hours.

  18. Computational and Experimental Study of an Industrial Centrifugal Compressor Volute

    HarriPitkanen; HannuEsa; 等


    A centrifugal compressor with a vaneless diffuser was studied experimentally and numericallly.The main target of the study was to analyze the volute flow.Two different volute geometries was studied.The numerical solution was done by using a steady-state RANS code at both design and off-design conditions.Both calculated and measured pressure and velocity distributions are presented.

  19. Spectroscopic studies of atomic and molecular species relevant to the optical fibre transmission bands

    Meldau, J


    The work presented in this thesis, although all relevant to wavelength standards in the optical fibre transmission windows at 1.3 mu m and 1.55 mu m, can be split into three main parts. Firstly, the work carried out at the University of Strathclyde concerning accurate line position measurements of some molecules having absorption bands at 1.5 mu m ( sup 1 sup 5 NH sub 3 , C sub 2 H sub 2 and sup 1 sup 3 C sup 1 sup 2 CH sub 2) and 1.3 mu m ( sup 1 sup 3 C sub 2 D-2 and sup 1 sup 2 C sub 2 D sub 2) with a Fourier transform spectrometer (FTS). The FTS measurements were undertaken primarily to provide a comprehensive list of fairly strong lines relevant to the optical fibre regions as potential wavelength references for the National Physical Laboratory (NPL). The sup 1 sup 3 C sup 1 sup 2 CH sub 2 overtone and combination bands were assigned and fitted. Secondly, the development of two diode laser spectrometers was carried out at the University of Strathclyde to perform an optical double resonance experiment in ...

  20. Experimental Study of Stable Surfaces for Anti-Slug Control in Multi-phase Flow

    Pedersen, Simon; Løhndorf, Petar Durdevic; Yang, Zhenyu


    The severe slugging flow is always challenging in oil & gas production, especially for the current offshore based production. The slugging flow can cause a lot of potential problems, such as those relevant to production safety, fatigue as well as capability. As one typical phenomenon in multi......-phase flow dynamics, the slug can be avoided or eliminated by proper facility design and control of operational conditions. Based on a testing facility which can emulate a pipeline-riser or a gas-lifted production well in a scaled-down manner, this paper experimentally studies the correlations of key...

  1. MOOSES: Multiple Option Observation System for Experimental Studies.

    Tapp, Jon; Wehby, Joseph

    The Multiple Option Observation System for Experimental Studies (MOOSES) is a flexible data collection and analysis package for applied behavioral research that addresses the needs of researchers interested in live coding of observational data. MOOSES allows the researcher to design a coding system for a particular research question. General types…

  2. Experimental and numerical study of an autonomous flap

    Bernhammer, L.O.; Navalkar, S.T.; Sodja, J.; De Breuker, R.; Karpel, M.


    This paper presents the experimental and numerical study of an autonomous load alleviation concept using trailing edge flaps. The flaps are autonomous units, which for instance can be used for gust load alleviation. The unit is self-powered and self-actuated through trailing edge tabs which are moun

  3. Real versus Simulated Mobile Phone Exposures in Experimental Studies

    Dimitris J. Panagopoulos


    Full Text Available We examined whether exposures to mobile phone radiation in biological/clinical experiments should be performed with real-life Electromagnetic Fields (EMFs emitted by commercially available mobile phone handsets, instead of simulated EMFs emitted by generators or test phones. Real mobile phone emissions are constantly and unpredictably varying and thus are very different from simulated emissions which employ fixed parameters and no variability. This variability is an important parameter that makes real emissions more bioactive. Living organisms seem to have decreased defense against environmental stressors of high variability. While experimental studies employing simulated EMF-emissions present a strong inconsistency among their results with less than 50% of them reporting effects, studies employing real mobile phone exposures demonstrate an almost 100% consistency in showing adverse effects. This consistency is in agreement with studies showing association with brain tumors, symptoms of unwellness, and declines in animal populations. Average dosimetry in studies with real emissions can be reliable with increased number of field measurements, and variation in experimental outcomes due to exposure variability becomes less significant with increased number of experimental replications. We conclude that, in order for experimental findings to reflect reality, it is crucially important that exposures be performed by commercially available mobile phone handsets.

  4. Experimental Study of the WEPTOS Wave Energy Converter

    Pecher, Arthur; Kofoed, Jens Peter; Marchalot, Tanguy

    This report presents the results of an experimental study on the power conversion capabilities and structural loads of the WEPTOS wave energy converter. The investigation focuses mainly at identifying the performance of the WEPTOS prototype in a wide range of production wave states and at the moo...

  5. Experimental Study on a Rotor for WEPTOS Wave Energy Converter

    Pecher, Arthur; Kofoed, Jens Peter; Marchalot, Tanguy

    This report presents the results of an experimental study of the power conversion capabilities of one single rotor of the WEPTOS wave energy converter. The investigation focuses mainly on defining the optimal weight distribution in the rotor in order to improve the hydraulic performance through...

  6. Experimental study of radioimmunotherapy versus chemotherapy for colorectal cancer

    Jong, G.M. de; Bleichrodt, R.P.; Eek, A.; Oyen, W.J.G.; Boerman, O.C.; Hendriks, T.


    BACKGROUND: Radioimmunotherapy (RIT) has been shown to reduce the incidence of local recurrence of colorectal cancer in an experimental model. The aim of the present study was to investigate the survival benefit of RIT compared with chemotherapy. METHODS: An anastomosis was constructed in male Wag/R

  7. Chemometric Optimization Studies in Catalysis Employing High-Throughput Experimentation

    Pereira, S.R.M.


    The main topic of this thesis is the investigation of the synergies between High-Throughput Experimentation (HTE) and Chemometric Optimization methodologies in Catalysis research and of the use of such methodologies to maximize the advantages of using HTE methods. Several case studies were analysed

  8. Experimental and numerical study of pulsating transversal jets

    Goldfeld, M. A.; Fedorova, N. N.; Fedorchenko, I. A.; Pozdnyakov, G. A.; Timofeev, K. Yu.; Zhakharova, Yu. V.


    Paper presents results of joint experimental and numerical investigation of pulsating jet penetration into still air and supersonic flow. Goal of the study is to investigate two-dimensional (2D) Hartmann generator (HG) properties and clear up its possibilities in providing better mixing between air and secondary (injected) gases.

  9. Public opinion polls, voter turnout, and welfare: An experimental study

    Großer, J.; Schram, A.


    We experimentally study the impact of public opinion poll releases on voter turnout and welfare in a participation game. We find higher overall turnout rates when polls inform the electroate about the levels of support for the candidates than when polls are prohibited. Distinguishing between allied

  10. Base flow and exhaust plume interaction. Part 1: Experimental study

    Schoones, M.M.J.; Bannink, W.J.


    An experimental study of the flow field along an axi-symmetric body with a single operating exhaust nozzle has been performed in the scope of an investigation on base flow-jet plume interactions. The structure of under-expanded jets in a co-flowing supersonic free stream was described using analytic

  11. Premium auctions and risk preferences: an experimental study

    Brunner, C.; Hu, A.; Oechssler, J.


    In premium auctions, the highest losing bidder receives a reward from the seller. This paper studies the private value English premium auction (EPA) for different risk attitudes of bidders. We explicitly derive the symmetric equilibrium for bidders with CARA utilities and conduct an experimental stu

  12. Experimental Studies of Few-nucleon Systems at Intermediate Energies

    Stephan, E.; Kistryn, St.; Kalantar-Nayestanaki, N.


    Systems composed of 3 nucleons are a subject of precise experimental studies for many years. At the first stage the investigations were mainly focused on elastic nucleon-deuteron scattering, slowly extending to systematic measurements of the deuteron breakup reaction. Intermediate energies, below th

  13. Capillary microreactors for lactic acid extraction: experimental and modelling study

    Susanti, Susanti; Winkelman, Jozef; Schuur, Boelo; Heeres, Hero; Yue, Jun


    Lactic acid is an important biobased chemical and, among others, is used for the production of poly-lactic acid. Down-stream processing using state of the art technology is energy intensive and leads to the formation of large amounts of salts. In this presentation, experimental and modeling studies

  14. Experimental Study of the Weptos Wave Energy Converter

    Pecher, Arthur; Kofoed, Jens Peter; Larsen, Tommy


    This paper presents the power performance results of the experimental study of the WEPTOS wave energy converter (WEC). This novel device combines an established and efficient wave energy absorbing mechanism with an adjustable structure that can regulate the amount of incoming wave energy and redu...

  15. Can Facebook Make Students Remember? An Experimental Study from Japan

    Acar, Adam


    This study experimentally manipulated the way students submit their assignments and tested the number of new words that are learned in each condition. The results showed that students who submitted their assignments through Facebook learned as much as those who submitted their assignment in a traditional way. In the light of these findings, we can…

  16. Surface roughness measurement using dichromatic speckle pattern: an experimental study.

    Fujii, H; Lit, J W


    Surface roughness is studied experimentally by making use of the statistical properties of dichromatic speckle patterns. The rms intensity difference between two speckle patterns produced by two argon laser lines are analyzed in the far field as functions of the object surface roughness and the difference in the two wavenumbers of the illuminating light. By applying previously derived formulas, the rms surface roughness is obtained from rms intensity differences. Glass and metal rough surfaces are used. Other than the scattering arrangement, the experimental setup has a simple spectrometric system and an electronic analyzing circuit.

  17. Theoretical and Experimental Study of Time Reversal in Cubic Crystals

    陆铭慧; 张碧星; 汪承灏


    The self-adaptive focusing of the time reversal in anisotropic media is studied theoretically and experimentally. It is conducted for the compressional wave field in the cubic crystal silicon. The experimental result is in agreement with our theoretical analysis. The focusing gain and the displacement distributions of the time reversal field are analysed in detail. It is shown that the waves from different elements of the transducer array arrive at the original place of the source simultaneously after the time reversal operation. The waveform distortions caused by the velocity anisotropy can automatically be compensated for after the time reversal processing.

  18. An experimental and numerical study of water jet cleaning process

    Guha, Anirban; Balachandar, Ram


    In this paper, we have experimentally, numerically and theoretically investigated the water jet cleaning process. Very high speed water jets (~80-200 m/s) are used in such cleaning operations. These jets diffuse in the surrounding atmosphere by the process of air entrainment and this contributes to the spreading of the jet and subsequent decay of pressure. Estimation of this pressure decay and subsequent placement of the cleaning object is of paramount importance in manufacturing and material processing industries. Also, the pressure distribution on the cleaning surface needs to be assessed in order to understand and optimize the material removal process. Experimental study is performed to understand the pressure characteristics. A Semi-empirical model for capturing the air entrainment has been added to the commercial CFD package FLUENT. The simulation results are validated against ours as well as previous experimental findings. The numerical results have shown that the optimal stand-off distance in cleaning ...

  19. Experimental study on CHF enhancement of plate by ultrasonic

    Kim, Dae Hun; Kweon, Young Chel [Sunmoon Univ., Asan (Korea, Republic of); Jeong, Ji Hwan [Chonan College of Foreign Studies, Chonan (Korea, Republic of)


    Augmentation of CHF by ultrasonic is experimentally studied under subcooling pool boiling condition. Experiment is carried out for downward-facing plate with and without the ultrasonic. The working fluid is distilled water. Experimental apparatus is composed of a bath, power supply, test section, ultrasonic generator, DAQ system. Experiment is performed with the subcooling temperature of 5 .deg. C, 20 .deg. C, 40 .deg. C and the inclined angle of 0 .deg., 10 .deg., 20 .deg., 45 .deg., 90 .deg.. From the experimental results, it is found that ultrasonic effect enhances CHF of the downward-facing plate. As increasing the degree of subcooling, the rate of CHF increase is enhanced. As increasing the inclined angle, the rate of CHF increase decreases. Also, we can see that the heat transfer mechanism of CHF augmentation is closely connected with the dynamic behavior of bubble generation and departure.

  20. Experimental models used for the study of antihepatotoxic agents

    Feroz Ahmad; Nahida Tabassum


    Both in vitro and in vivo liver models have been developed in the past years to study the hepatoprotective agents. These systems measure the ability of the test drug to prevent or cure liver toxicity (induced by various hepatotoxins) in experimental animals. In in vitro models fresh hepatocytes are treated with hepatotoxin and the effect of the test drug on the same is evaluated. In in vivo models, a toxic dose or repeated doses of a known hepatotoxin are administered to induce liver damage in experimental animals. The test substance is administered along with, prior to and/or after the toxin treatment. Various chemical agents normally used to induce hepatotoxicty in experimental animals for the evaluation of hepatoprotective agents include carbon tetrachloride, paracetamol, Acrylamide, adriamycin, alcohol, antitubercular drugs etc. The present article explains the mechanism of action of various hepatotoxic chemical/drugs, their dosage and route of administration.

  1. Experimental study of photo counting imaging based on APD

    Qu, Huiming; Li, Yuan-yuan; Cao, Dan; Zheng, Qi; Ji, Zhong-Jie; Chen, Qian


    Photo counting imaging is a promising imaging method for very low-level-light condition and super high-speed imaging. An experimental setup with Geiger mode silicon avalanche photodiode single-photon counter was established in this study. This experimental setup achieved photon counting imaging through serial two-dimensional scanning mode of single APD. It extracts the extremely weak signal from the noise by scanning image, and then reconstructs the photon distribution image. The feasibility of the experiment platform was verified with many experiments. The resolution bar was scanned and imaged in different lighting condition. A Lena image was also scanned and imaged among several illumination conditions. The resolution ability and imaging quality are evaluated in different illumination surroundings. The imaging limited condition was concluded based on existing APD sensor. The experimental result indicates that the imaging based Geiger mode APD is an excellent candidate for very low level light imaging.

  2. Experimental and theoretical study on hollow-cone spray

    Chang, Keh-Chin; Wang, Muh-Rong; Wu, Wen-Jing; Hong, Chia-Hong


    A theoretical and experimental investigation has been conducted to study the two-phase turbulent structure in an isothermal hollow-cone spray. Mean and fluctuating velocity components, drop number density, as well as drop-size distribution were measured with a nonintrusive diagnostic tool, a two-component phase Doppler particle analyzer. Complete initial conditions required for theoretical calculations were also provided with measurements. Theoretical calculations were made with an Eulerian-Lagrangian formulism. Turbulent dispersion effects were numerically simulated using a Monte Carlo method. Turbulence modulation effects were also taken into account in the modeling. The well-defined experimental data were used to assess the accuracy of the resultant Eulerian-Lagrangian model. Comparisons showed that the theoretical predictions, based upon the Eulerian-Lagrangian model, yielded reasonable agreement with the experimental data. The improvements made by inclusion of the selected turbulence modulation model were insignificant in this work.


    Omole Moses Kayode


    Full Text Available This prospective study was carried out in a state hospital, Sokemu, Abeokuta to determine the relevance of Drug Information Centre (DIC to the practice of Health Care Professionals in the Hospital. A total of 120 questionnaires were administered to the hospital health care professionals. Total number of respondents was 107 corresponding to 89.2% of the total population with years of experience in service ranging from 5- 15 years.Eighty five 85 (79.4% believed that Drug Information Centre was relevant to their professional practice, 12 (11.2% believed that it was not relevant to their professional practice, while 10 (9.4% were not sure of the relevance of the DIC to their professional practice.Forty three (43 (19.2% respondents required latest Information on drugs, 25 (11.2% required information on side effects, 29 (12.9% on dosage form, 27 (12.1% on dosage regimen, 12 (5.4% on indications, 27 (12.1% on contra-indications, 19 (8.5% on brand names and 21 (9.4% required drug information on all the listed areas.Forty seven (47 (43.9% claimed that they obtained Drug Information from relevant textbooks, 74 (69.2% from colleagues, 16 (15.0% from internet, 23 (21.5% from journal and largest number 102 (95.3% claimed they obtained information from the Pharmacists who are medical representatives of pharmaceutical companies as well as from hospital pharmacists.Drug Information Centre was found to be relevant to the practice of health care professionals at a state hospital, Sokemu in Abeokuta, Nigeria. Hypothesis testing showed significant relationship of p<0.05.

  4. Experimental and numerical study of open-air active cooling

    Al-Fifi, Salman Amsari

    The topic of my thesis is Experimental and Numerical Study of Open Air Active Cooling. The present research is intended to investigate experimentally and Numerically the effectiveness of cooling large open areas like stadiums, shopping malls, national gardens, amusement parks, zoos, transportation facilities and government facilities or even in buildings outdoor gardens and patios. Our cooling systems are simple cooling fans with different diameters and a mist system. This type of cooling systems has been chosen among the others to guarantee less energy consumption, which will make it the most favorable and applicable for cooling such places mentioned above. In the experiments, the main focus is to study the temperature domain as a function of different fan diameters aerodynamically similar in different heights till we come up with an empirical relationship that can determine the temperature domain for different fan diameters and for different heights of these fans. The experimental part has two stages. The first stage is devoted to investigate the maximum range of airspeed and profile for three different fan diameters and for different heights without mist, while the second stage is devoted to investigate the maximum range of temperature and profile for the three different diameter fans and for different heights with mist. The computational study is devoted to built an experimentally verified mathematical model to be used in the design and optimization of water mist cooling systems, and to compare the mathematical results to the experimental results and to get an insight of how to apply such evaporative mist cooling for different places for different conditions. In this study, numerical solution is presented based on experimental conditions, such dry bulb temperature, wet bulb temperature, relative humidity, operating pressure and fan airspeed. In the computational study, all experimental conditions are kept the same for the three fans except the fan airspeed

  5. Deep learning relevance

    Lioma, Christina; Larsen, Birger; Petersen, Casper


    train a Recurrent Neural Network (RNN) on existing relevant information to that query. We then use the RNN to "deep learn" a single, synthetic, and we assume, relevant document for that query. We design a crowdsourcing experiment to assess how relevant the "deep learned" document is, compared......What if Information Retrieval (IR) systems did not just retrieve relevant information that is stored in their indices, but could also "understand" it and synthesise it into a single document? We present a preliminary study that makes a first step towards answering this question. Given a query, we...... to existing relevant documents. Users are shown a query and four wordclouds (of three existing relevant documents and our deep learned synthetic document). The synthetic document is ranked on average most relevant of all....

  6. Pseudoepitheliomatous hyperplasia after diode laser oral surgery. An experimental study

    Seoane, Juan; González-Mosquera, Antonio; García-Martín, José-Manuel; García-Caballero, Lucía; Varela-Centelles, Pablo


    Background To examine the process of epithelial reparation in a surgical wound caused by diode laser. Material and Methods An experimental study with 27 Sprage-Dawley rats was undertaken. The animals were randomly allocated to two experimental groups, whose individuals underwent glossectomy by means of a diode laser at different wattages, and a control group treated using a number 15 scalpel blade. The animals were slaughtered at the 2nd, 7th, and 14th day after glossectomy. The specimens were independently studied by two pathologists (blinded for the specimens’ group). Results At the 7th day, re-epithelisation was slightly faster for the control group (conventional scalpel) (p=0.011). At the 14th day, complete re-epithelization was observed for all groups. The experimental groups displayed a pseudoepitheliomatous hyperplasia. Conclusions It is concluded that, considering the limitations of this kind of experimental studies, early re-epithelisation occurs slightly faster when a conventional scalpel is used for incision, although re-epithelisation is completed in two weeks no matter the instrument used. In addition, pseudoepitheliomatous hyperplasia is a potential event after oral mucosa surgery with diode laser. Knowledge about this phenomenon (not previously described) may prevent diagnostic mistakes and inadequate treatment approaches, particularly when dealing with potentially malignant oral lesions. Key words:Diode laser, animal model, oral biopsy, oral cancer, oral precancer, pseudoepitheliomatous hyperplasia. PMID:26116841

  7. Experimental asbestos studies in the UK: 1912-1950.

    Greenberg, Morris


    The asbestos industry originated in the UK in the 1870s. By 1898, asbestos had many applications and was reported to be one of the four leading causes of severe occupational disease. In 1912, the UK government sponsored an experimental study that reported that exposure to asbestos produced no more than a modicum of pulmonary fibrosis in guinea pigs. In the 1930s, the newly established Medical Research Council, with assistance from industry, sponsored a study of the effects of exposing animals to asbestos by injection (intratracheal and subcutaneous) and by inhalation in the factory environment. Government reports, publications, and contemporary records obtained by legal discovery have been reviewed in the context of the stage of scientific development and the history of the times. Experimenters were engaged in a learning process during the 1912-1950 period, and their reports of the effects of asbestos were inconsistent. Pathologists who studied the effects of asbestos experimentally, at whole animal, tissue and cellular levels, advanced experimental methodology and mechanistic knowledge. In the hands of public relations experts, however, research was exploited to preserve an industry and perpetuate preventable diseases, a practice that continues to this day. © 2017 Wiley Periodicals, Inc.

  8. Study about the relevance and the disclosure of biological assets of listed companies in BM&FBOVESPA

    Luciana Holtz


    Full Text Available The main objective this article is to verify that the information content of biological assets disclosed in the financial statements are relevant and, the secondary objective perform content analysis of the notes verifying the compliance of information supplied by entities with CPC 29. The study sample was composed of publicly traded stock companies listed on the BM & FBOVESPA with data for the year 2010 and 2011. The empirical tests were conducted applying relevance models, using observations of 347 active companies characterizing a study model pooled ordinary least squares – POLS, including companies that have reported biological assets into account specific .The companies that had values of biological assets posted have had analyzed explanatory notes referring to this account. The results provide empirical evidence that the information content of biological assets disclosed by companies is not relevant to the sample. In relation the content analysis of the notes was checked a partial compliance of the standard, there is a disparity in the information disclosure practices by the companies analyzed, as well as an omission of items required by the standard. Can be inferred that loss of the relevance has occurred, in part, by the poor quality of the notes, which may make it difficult for outside users in interpreting the information disclosed.

  9. Experimental Study of Explosion Limits of Refrigerants and Lubricants’ Mixture

    Shi, Y.Q.; Chen, Guangming; Chen, Q.


    The explosion limits of refrigerants and lubricants’ mixture were studied. The refrigerants like R161, R1234yf and R152a are combustible. Lubricants, to a certain extent, are combustion-supporting. In many actual conditions, lubricants and refrigerants are mixed together. In this paper, a test device which can be run automatically was established according to ASTM E681-09, and the explosive experimental of refrigerants and lubricants’ mixture in some ratio was studied. By altering the proport...

  10. Experimental Studies on Thermal and Electrical Properties of Platinum Nanofilms

    ZHANG Xing; ZHANG Qing-Guang; CAO Bing-Yang; FUJII Motoo; TAKAHASHI Koji; IKUTA Tatsuya


    @@ We experimentally studied the in-plane thermal and electrical properties of a suspended platinum nanofilm in thickness of 15 nm. The measured results show that the in-plane thermal conductivity, the electrical conductivity and the resistance-temperature coefficient of the studied nanofilm are much less than those of the bulk material,while the Lorenz number is greater than the bulk value.

  11. Experimental and Analytical Studies of Solar System Chemistry

    Burnett, Donald S.


    The cosmochemistry research funded by this grant resulted in the publications given in the attached Publication List. The research focused in three areas: (1) Experimental studies of trace element partitioning. (2) Studies of the minor element chemistry and O isotopic compositions of MgAlO4 spinels from Ca-Al-Rich Inclusions in carbonaceous chondrite meteorites, and (3) The abundances and chemical fractionations of Th and U in chondritic meteorites.

  12. Experimental endotoxemia as a model to study neuroimmune mechanisms in human visceral pain.

    Benson, Sven; Engler, Harald; Schedlowski, Manfred; Elsenbruch, Sigrid


    The administration of bacterial endotoxin (i.e., lipopolysaccharide, LPS) constitutes a well-established experimental approach to study the effects of an acute and transient immune activation on physiological, behavioral, and emotional aspects of sickness behavior in animals and healthy humans. However, little is known about possible effects of experimental endotoxemia on pain in humans. This knowledge gap is particularly striking in the context of visceral pain in functional as well as chronic-inflammatory gastrointestinal disorders. Although inflammatory processes have been implicated in the pathophysiology of visceral pain, it remains incompletely understood how inflammatory mediators interact with bottom-up (i.e., increased afferent input) and top-down (i.e., altered central pain processing) mechanisms of visceral hyperalgesia. Considering the recent findings of visceral hyperalgesia after LPS application in humans, in this review, we propose that experimental endotoxemia with its complex peripheral and central effects constitutes an experimental model to study neuroimmune communication in human pain research. We summarize and attempt to integrate relevant animal and human studies concerning neuroimmune communication in visceral and somatic pain, discuss putative mechanisms, and conclude with future research directions. © 2012 New York Academy of Sciences.

  13. Experimental Studies of the Transport Parameters of Warm Dense Matter

    Chouffani, Khalid [Idaho State Univ., Pocatello, ID (United States)


    There is a need to establish fundamental properties of matter and energy under extreme physical conditions. Although high energy density physics (HEDP) research spans a wide range of plasma conditions, there is one unifying regime that is of particular importance and complexity: that of warm dense matter, the transitional state between solid state condensed matter and energetic plasmas. Most laboratory experimental conditions, including inertial confinement implosion, fall into this regime. Because all aspects of laboratory-created high-energy-density plasmas transition through the warm dense matter regime, understanding the fundamental properties to determine how matter and energy interact in this regime is an important aspect of major research efforts in HEDP. Improved understanding of warm dense matter would have significant and wide-ranging impact on HEDP science, from helping to explain wire initiation studies on the Sandia Z machine to increasing the predictive power of inertial confinement fusion modeling. The central goal or objective of our proposed research is to experimentally determine the electrical resistivity, temperature, density, and average ionization state of a variety of materials in the warm dense matter regime, without the use of theoretical calculations. Since the lack of an accurate energy of state (EOS) model is primarily due to the lack of experimental data, we propose an experimental study of the transport coefficients of warm dense matter.

  14. Peristaltic flow of a fluid in a porous channel: A study having relevance to flow of bile within ducts in a pathological state

    Maiti, S; 10.1016/j.ijengsci.2011.05.006


    The paper deals with a theoretical study of the transport of a fluid in a channel, which takes place by the phenomenon of peristalsis. A mathematical analysis of the said problem has been presented. The analysis involves the application of a suitable perturbation technique. The velocity profile and the critical pressure for the occurrence of reflux are investigated with particular emphasis by using appropriate numerical methods. The effects of various parameters, such as Reynolds number, pressure gradient, porosity parameter, Darcy number, slip parameter, amplitude ratio and wave number on velocity and critical pressure for reflux are investigated in detail. The computed results are compared with a previous analytical work and an experimental investigation reported earlier in existing scientific literatures. The results of the present study are in conformity to both of them. The study has got some relevance to the physiological flow of bile in the common bile duct in a pathological state. It reveals that in t...

  15. Experimental Study of Stable Surfaces for Anti-Slug Control in Multi-phase Flow

    Pedersen, Simon; Løhndorf, Petar Durdevic; Stampe, Kasper;


    Severe slugging flow is always challenging in oil & gas production, especially for the current offshore based production. The slugging flow can cause a lot of problems, such as those relevant to production safety, fatigue as well as capability. As one typical phenomenon in multi-phase flow dynamics......, the slug can be avoided or eliminated by proper facility design or control of operational conditions. Based on a testing facility which can emulate a pipeline-riser or a gas-lifted production well in a scaled-down manner, this paper experimentally studies the correlations of key operational parameters...... that the capability, performance and efficiency of anti-slug control can be dramatically improved if these stable surfaces can be experimentally determined beforehand. The paper concludes that obtaining the stable surface on the new developed map can significantly improve the production rate in a control scheme. Even...

  16. Franz Brentano and the beginning of experimental psychology: implications for the study of psychological phenomena today.

    Meyer, Andreas; Hackert, Benedikt; Weger, Ulrich


    The manifestation of psychology as an academic discipline more than a 100 years ago was accompanied by a paradigm shift in our understanding of psychological phenomena-with both its light and shadow sides. On the one hand, this development allowed for a rigorous and experimentation-based approach to psychological phenomena; on the other, it led to an alienation from the experiential-or qualia-facets as the topics under inquiry were researched increasingly through third-person (e.g., behavioral or physiological) measures. At the turning point of this development stood an eminent but little known European scholar, Franz Brentano, who called for a synthesis of both third-person and first-person research methods in the study of psychological phenomena. On the occasion of his death, a hundred years ago on March 17, 1917 we wish to illustrate the historical background, introduce the reader to Brentano's approach and work and discuss its relevance for experimental psychology today.

  17. Deep Boreholes Seals Subjected to High P, T conditions – Preliminary Experimental Studies

    Caporuscio, Florie Andre [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Norskog, Katherine Elizabeth [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Maner, James Lavada [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)


    The objective of this planned experimental work is to evaluate physio-chemical processes for ‘seal’ components and materials relevant to deep borehole disposal. These evaluations will encompass multi-laboratory efforts for the development of seals concepts and application of Thermal-Mechanical-Chemical (TMC) modeling work to assess barrier material interactions with subsurface fluids, their stability at high temperatures, and the implications of these processes to the evaluation of thermal limits. Deep borehole experimental work will constrain the Pressure, Temperature (P, T) conditions which “seal” material will experience in deep borehole crystalline rock repositories. The rocks of interest to this study include the silicic (granitic gneiss) end members. The experiments will systematically add components to capture discrete changes in both water and EBS component chemistries.

  18. Experimental and Theoretical Studies in Hydrogen-Bonding Organocatalysis

    Matej Žabka


    Full Text Available Chiral thioureas and squaramides are among the most prominent hydrogen-bond bifunctional organocatalysts now extensively used for various transformations, including aldol, Michael, Mannich and Diels-Alder reactions. More importantly, the experimental and computational study of the mode of activation has begun to attract considerable attention. Various experimental, spectroscopic and calculation methods are now frequently used, often as an integrated approach, to establish the reaction mechanism, the mode of activation or explain the stereochemical outcome of the reaction. This article comprises several case studies, sorted according to the method used in their study. The aim of this review is to give the investigators an overview of the methods currently utilized for mechanistic investigations in hydrogen-bonding organocatalysis.

  19. Experimental and Theoretical Study on Pyrolysis of Isopsoralen

    Jiu-zhong Yang; Feng Zhang; Liang-yuan Jia; Li-dong Zhang; Fei Qi; Hai-yan Fan; Ji-bao Cai


    The pyrolysis of isopsoralen was studied by synchrotron vacuum ultraviolet photoionization mass spectrometry at low pressure.The pyrolysis products were detected at different photon energies,the ratios of products to precursor were measured at various pyrolysis temperatures.The experimental results demonstrate that the main pyrolysis products are primary CO and sequential CO elimination products (C10H6O2 and C9H6O).The decomposition channels of isopsoralen were also studied by the density functional theory,then rate constants for competing pathways were calculated by the transition state theory.The dominant decomposition channels of isopsoralen and the molecular structures for corresponding products were identified bv combined experimental and theoretical studies.

  20. Experimental study of elementary collection efficiency of aerosols by spray: Design of the experimental device

    Ducret, D.; Vendel, J.; Garrec. S.L.


    The safety of a nuclear power plant containment building, in which pressure and temperature could increase because of a overheating reactor accident, can be achieved by spraying water drops. The spray reduces the pressure and the temperature levels by condensation of steam on cold water drops. The more stringent thermodynamic conditions are a pressure of 5.10{sup 5} Pa (due to steam emission) and a temperature of 413 K. Moreover its energy dissipation function, the spray leads to the washout of fission product particles emitted in the reactor building atmosphere. The present study includes a large program devoted to the evaluation of realistic washout rates. The aim of this work is to develop experiments in order to determine the collection efficiency of aerosols by a single drop. To do this, the experimental device has to be designed with fundamental criteria:-Thermodynamic conditions have to be representative of post-accident atmosphere. Thermodynamic equilibrium has to be attained between the water drops and the gaseous phase. Thermophoretic, diffusiophoretic and mechanical effects have to be studied independently. Operating conditions have to be homogenous and constant during each experiment. This paper presents the design of the experimental device. In practice, the consequences on the design of each of the criteria given previously and the necessity of being representative of the real conditions will be described.

  1. Palaeobotanical studies from tropical Africa: relevance to the evolution of forest, woodland and savannah biomes.

    Jacobs, Bonnie F


    Fossil plants provide data on climate, community composition and structure, all of which are relevant to the definition and recognition of biomes. Macrofossils reflect local vegetation, whereas pollen assemblages sample a larger area. The earliest solid evidence for angiosperm tropical rainforest in Africa is based primarily on Late Eocene to Late Oligocene (ca. 39-26 Myr ago) pollen assemblages from Cameroon, which are rich in forest families. Plant macrofossil assemblages from elsewhere in interior Africa for this time interval are rare, but new work at Chilga in the northwestern Ethiopian Highlands documents forest communities at 28 Myr ago. Initial results indicate botanical affinities with lowland West African forest. The earliest known woodland community in tropical Africa is dated at 46 Myr ago in northern Tanzania, as documented by leaves and fruits from lake deposits. The community around the lake was dominated by caesalpinioid legumes, but included Acacia, for which this, to my knowledge, is the earliest record. This community is structurally similar to modern miombo, although it is different at the generic level. The grass-dominated savannah biome began to expand in the Middle Miocene (16 Myr ago), and became widespread in the Late Miocene (ca. 8 Myr ago), as documented by pollen and carbon isotopes from both West and East Africa.

  2. In Vitro Studies of the Activity of Dithiocarbamate Organoruthenium Complexes against Clinically Relevant Fungal Pathogens

    Claudio L. Donnici


    Full Text Available The in vitro antifungal activity of nine dirutheniumpentadithiocarbamate complexes C1–C9 was investigated and assessed for its activity against four different fungal species with clinical interest and related to invasive fungal infections (IFIs, such as Candida spp. [C. albicans (two clinical isolates, C. glabrata, C. krusei, C. parapsolisis, C. tropicalis, C.dubliniensis (six clinical isolates], Paracoccidioides brasiliensis (seven clinical isolates, Cryptococcus neoformans and Sporothrix schenckii. All synthesized complexes C1–C9 and also the free ligands L1–L9 were submitted to in vitro tests against those fungi and the results are very promising, since some of the obtained MIC (minimal inhibitory concentration values were very low (from 10−6 mol mL−1 to 10−8 mol mL−1 against all investigated clinically relevant fungal pathogens, except for C. glabrata, that the MIC values are close to the ones obtained for fluconazole, the standard antifungal agent tested. Preliminary structure-activity relations (SAR might be suggested and a strong influence from steric and lipophilic parameters in the antifungal activity can be noticed. Cytotoxicity assays (IC50 showed that the complexes are not as toxic (IC50 values are much higher—30 to 200 fold—than MIC values. These ruthenium complexes are very promising lead compounds for novel antifungal drug development, especially in IFIs, one of most harmful emerging infection diseases (EIDs.

  3. Perceptions of document relevance

    Peter eBruza


    Full Text Available This article presents a study of how humans perceive the relevance of documents.Humans are adept at making reasonably robust and quick decisions about what information is relevant to them, despite the ever increasing complexity and volume of their surrounding information environment. The literature on document relevance has identified various dimensions of relevance (e.g., topicality, novelty, etc., however little is understood about how these dimensions may interact.We performed a crowdsourced study of how human subjects judge two relevance dimensions in relation to document snippets retrieved from an internet search engine.The order of the judgement was controlled.For those judgements exhibiting an order effect, a q-test was performed to determine whether the order effects can be explained by a quantum decision model based on incompatible decision perspectives.Some evidence of incompatibility was found which suggests incompatible decision perspectives is appropriate for explaining interacting dimensions of relevance.

  4. The Effectiveness of Hypnosis Intervention for Labor: An Experimental Study.

    Beevi, Zuhrah; Low, Wah Yun; Hassan, Jamiyah


    Hypnosis has been shown to help pregnant women experience improved labor and postpartum periods. The present study compares the differences between experimental (n = 23) and control groups (n = 22) on specific variables measured both during labor and 24 hr postpartum. The participants in the experimental group received the hypnosis intervention at weeks 16, 20, 28, and 36 of pregnancy, while those in the control group received only routine antenatal care. The data collected at the labor stage describe the length of the labor stage, pain relief used during labor, the method of delivery, and the type of assisted vaginal delivery. Within 24 hr of delivery, data on neonatal birth weight, neonatal Apgar scores, and self-reported pain were obtained. The labor stage results showed no significant differences in the length of the second and third stages of labor. Although the participants in the experimental group reported higher pain levels immediately prior to, during, and immediately after delivery, their use of pethidine during labor was significantly lower than the control group participants. None of the experimental group participants opted for an epidural, and they had a greater number of assisted vaginal deliveries than the control group participants. The 24 hr postpartum results showed that the neonates of the experimental group participants had nonsignificantly higher Apgar scores than those of the women in the control group. Group differences in neonatal weight were not significant. The results of the present study indicate that hypnosis is useful for assisting pregnant women during labor and the postpartum period.

  5. Selecting appropriate animal models and experimental designs for endocrine disruptor research and testing studies.

    Stokes, William S


    Evidence that chemicals in the environment may cause developmental and reproductive abnormalities in fish and wildlife by disrupting normal endocrine functions has increased concern about potential adverse human health effects from such chemicals. US laws have now been enacted that require the US Environmental Protection Agency (EPA) to develop and validate a screening program to identify chemicals in food and water with potential endocrine-disrupting activity. EPA subsequently proposed an Endocrine Disruptor Screening Program that uses in vitro and in vivo test systems to identify chemicals that may adversely affect humans and ecologically important animal species. However, the endocrine system can be readily modulated by many experimental factors, including diet and the genetic background of the selected animal strain or stock. It is therefore desirable to minimize or avoid factors that cause or contribute to experimental variation in endocrine disruptor research and testing studies. Standard laboratory animal diets contain high and variable levels of phytoestrogens, which can modulate physiologic and behavioral responses similar to both endogenous estrogen as well as exogenous estrogenic chemicals. Other studies have determined that some commonly used outbred mice and rats are less responsive to estrogenic substances than certain inbred mouse and rat strains for various estrogen-sensitive endpoints. It is therefore critical to select appropriate biological models and diets for endocrine disruptor studies that provide optimal sensitivity and specificity to accomplish the research or testing objectives. An introduction is provided to 11 other papers in this issue that review these and other important laboratory animal experimental design considerations in greater detail, and that review laboratory animal and in vitro models currently being used or evaluated for endocrine disruptor research and testing. Selection of appropriate animal models and experimental design

  6. Development and Experimental Validation of Large Eddy Simulation Techniques for the Prediction of Combustion-Dynamic Process in Syngas Combustion: Characterization of Autoignition, Flashback, and Flame-Liftoff at Gas-Turbine Relevant Operating Conditions

    Ihme, Matthias [Univ. of Michigan, Ann Arbor, MI (United States); Driscoll, James [Univ. of Michigan, Ann Arbor, MI (United States)


    The objective of this closely coordinated experimental and computational research effort is the development of simulation techniques for the prediction of combustion processes, relevant to the oxidation of syngas and high hydrogen content (HHC) fuels at gas-turbine relevant operating conditions. Specifically, the research goals are (i) the characterization of the sensitivity of syngas ignition processes to hydrodynamic processes and perturbations in temperature and mixture composition in rapid compression machines and ow-reactors and (ii) to conduct comprehensive experimental investigations in a swirl-stabilized gas turbine (GT) combustor under realistic high-pressure operating conditions in order (iii) to obtain fundamental understanding about mechanisms controlling unstable flame regimes in HHC-combustion.

  7. [Mood-congruent effect in self-relevant information processing: a study using an autobiographical memory recall task].

    Itoh, M


    The pattern of the mood-congruent effect in an autobiographical memory recall task was investigated. Each subject was randomly assigned to one of three experimental conditions: positive mood, negative mood (induced with music), and control groups (no specific mood). Subjects were then presented with a word at a time from a list of trait words, which were pleasant or unpleasant. They decided whether they could recall any of their autobiographical memories related to the word, and responded with "yes" or "no" buttons as rapidly and accurately as possible. After the task, they were given five minutes for an incidental free recall test. Results indicated that the mood-congruent effect was found regardless of whether there was an autobiographical memory related to the word or not in both positive and negative mood states. The effect of moods on self-relevant information processing was discussed.

  8. Development of a novel, physiologically relevant cytotoxicity model: Application to the study of chemotherapeutic damage to mesenchymal stromal cells

    May, Jennifer E., E-mail:; Morse, H. Ruth, E-mail:; Xu, Jinsheng, E-mail:; Donaldson, Craig, E-mail:


    There is an increasing need for development of physiologically relevant in-vitro models for testing toxicity, however determining toxic effects of agents which undergo extensive hepatic metabolism can be particularly challenging. If a source of such metabolic enzymes is inadequate within a model system, toxicity from prodrugs may be grossly underestimated. Conversely, the vast majority of agents are detoxified by the liver, consequently toxicity from such agents may be overestimated. In this study we describe the development of a novel in-vitro model, which could be adapted for any toxicology setting. The model utilises HepG2 liver spheroids as a source of metabolic enzymes, which have been shown to more closely resemble human liver than traditional monolayer cultures. A co-culture model has been developed enabling the effect of any metabolised agent on another cell type to be assessed. This has been optimised to enable the study of damaging effects of chemotherapy on mesenchymal stem cells (MSC), the supportive stem cells of the bone marrow. Several optimisation steps were undertaken, including determining optimal culture conditions, confirmation of hepatic P450 enzyme activity and ensuring physiologically relevant doses of chemotherapeutic agents were appropriate for use within the model. The developed model was subsequently validated using several chemotherapeutic agents, both prodrugs and active drugs, with resulting MSC damage closely resembling effects seen in patients following chemotherapy. Minimal modifications would enable this novel co-culture model to be utilised as a general toxicity model, contributing to the drive to reduce animal safety testing and enabling physiologically relevant in-vitro study. -- Highlights: ► An in vitro model was developed for study of drugs requiring hepatic metabolism ► HepG2 spheroids were utilised as a physiologically relevant source of liver enzymes ► The model was optimised to enable study of chemotherapeutic

  9. High Energy Density Plasmas (HEDP) for studies of basic nuclear science relevant to Stellar and Big Bang Nucleosynthesis

    Frenje, Johan


    Thermonuclear reaction rates and nuclear processes have been explored traditionally by means of conventional accelerator experiments, which are difficult to execute at conditions relevant to stellar nucleosynthesis. Thus, nuclear reactions at stellar energies are often studied through extrapolations from higher-energy data or in low-background underground experiments. Even when measurements are possible using accelerators at relevant energies, thermonuclear reaction rates in stars are inherently different from those in accelerator experiments. The fusing nuclei are surrounded by bound electrons in accelerator experiments, whereas electrons occupy mainly continuum states in a stellar environment. Nuclear astrophysics research will therefore benefit from an enlarged toolkit for studies of nuclear reactions. In this presentation, we report on the first use of High Energy Density Plasmas for studies of nuclear reactions relevant to basic nuclear science, stellar and Big Bang nucleosynthesis. These experiments were carried out at the OMEGA laser facility at University of Rochester and the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory, in which spherical capsules were irradiated with powerful lasers to compress and heat the fuel to high enough temperatures and densities for nuclear reactions to occur. Four experiments will be highlighted in this presentation. In the first experiment, the differential cross section for the elastic neutron-triton (n-T) scattering at 14.1 MeV was measured with significantly higher accuracy than achieved in accelerator experiments. In the second experiment, the T(t,2n)4He reaction, a mirror reaction to the 3He(3He,2p)4He reaction that plays an important role in the proton-proton chain that transforms hydrogen into ordinary 4He in stars like our Sun, was studied at energies in the range 15-40 keV. In the third experiment, the 3He+3He solar fusion reaction was studied directly, and in the fourth experiment, we

  10. Lung Morphological Changes in Closed Chest Injury (an experimental study

    A. M. Golubev


    Full Text Available Objective: to study lung morphological changes in a closed chest injury model in laboratory animals. Material and methods. Experiments were carried out in 30 male albino nonbred rats weighing 350—380 g. Closed chest injury was simulated, by exposing the chest of anesthetized rats to a 300-g metal cylinder falling from a height of 30 cm. The observation periods were 1, 3, 6, and 24 hours. Results. The signs of evident perivenular edema that was uncharas-teristic to acute respiratory distress syndrome induced by other causes are an important peculiarity of lung morphological changes in this experimental model of closed chest injury. Conclusion. The experimental studies clarified the pattern of lung morphological changes in the early period after closed chest injury. Key words: closed chest injury, pulmonary edema.

  11. Experimental Vibration Study on the Healthy and Delaminated Composite Plates

    Ullah, Israr; Sinha, Jyoti K, E-mail: [School of Mechanical, Aerospace and Civil Engineering, University of Manchester, Manchester M13 9PL (United Kingdom)


    Vibration based damage, in particular delamination detection, in the composite structures is an active research area. The present study is also on the dynamics of the composite plates with and without delamination based on the experimental study. The test plate made of E-glass fibre and epoxy resins has been used here. A piezo-electric shaker has been used to excite the composite plate and the acceleration responses were measured using the number of accelerometers. The dynamics of the delaminated composite plates were then compared with a healthy composite plate when the vibration experiments have been conducted at the lower modes. The paper will discuss the observations made on the measured vibration responses from both the healthy and the delaminated plates and the possibility of the delamination detection from the experimental vibration data.

  12. A Combined Theoretical and Experimental Study for Silver Electroplating

    Liu, Anmin; Ren, Xuefeng; An, Maozhong; Zhang, Jinqiu; Yang, Peixia; Wang, Bo; Zhu, Yongming; Wang, Chong


    A novel method combined theoretical and experimental study for environmental friendly silver electroplating was introduced. Quantum chemical calculations and molecular dynamic (MD) simulations were employed for predicting the behaviour and function of the complexing agents. Electronic properties, orbital information, and single point energies of the 5,5-dimethylhydantoin (DMH), nicotinic acid (NA), as well as their silver(I)-complexes were provided by quantum chemical calculations based on density functional theory (DFT). Adsorption behaviors of the agents on copper and silver surfaces were investigated using MD simulations. Basing on the data of quantum chemical calculations and MD simulations, we believed that DMH and NA could be the promising complexing agents for silver electroplating. The experimental results, including of electrochemical measurement and silver electroplating, further confirmed the above prediction. This efficient and versatile method thus opens a new window to study or design complexing agents for generalized metal electroplating and will vigorously promote the level of this research region.

  13. Relevance between the degree of industrial competition and fair value information: Study on the listed companies in China

    Xuemin Zhuang


    Full Text Available Purpose: The purpose of this article is to study whether there exists natural relationship between fair value and corporate external market. A series of special phenomenon in the application of fair value arouses our research interests, which present evidences on how competition affects the correlation of fair value information. Design/methodology/approach: this thesis chooses fair value changes gains and losses and calculate the ratio of DFVPSit as the alternative variable of the fair value. In order to effectively inspect the mutual influence between the degree of industry competition and the value relevance of fair value, and reduce the impact of multi-collinearity, we built a regression model on the hypothesis, which supposes that if other conditions are the same, the fair value information has greater value relevance if the degree of the industry competition is greater. To test the hypothesis, we use the comparison of the DFVPSit coefficient absolute value to judge the value relevance of fair value information, and the greater the absolute value is, the higher relevance between the changes in fair value per share profits and losses with the stock prices. Findings: The higher the degree of competition in the industry is, the more fair value information relevance is. Also, there are evidences representing that fair value information often presents negative correlation with the stock price. Originality/value: The main contribution of the article is to show that not only need we make the formulation and implementation of the high quality of fair value accounting standards to suit for both the national conditions and international practice, but also need we further to improve the company's external governance mechanism to promote fair value’s information correlation.

  14. An experimental study of a pin-fin heat exchanger

    Ramthun, David L.


    Approved for public release; distribution is unlimited A detailed experimental study has been carried out on the heat transfer and pressure drop characteristics of a compact heat exchanger with pin fins. A modular wind-tunnel with a rectangular cross-section duct-flow area was constructed that would accommodate the heat exchanger test section with varying pin designs. The flow in the tunnel was achieved through a suction-type blower, and a leading entrance length section was added to achie...

  15. Comparative study of experimental signals for multipactor and breakdown.

    Dehler, Micha; Wuensch, Walter; Faus-Golfe, Angeles; Gimeno Martinez, Benito; Kovermann, Jan; Boria, Vicente; Raboso, David


    Performance limiting high-power rf phenomenon occur in both transmitter systems in satellites and high-gradient accelerating structures in particle accelerators. In satellites the predominant effect is multipactor while in accelerators it is breakdown. Both communities have studied their respective phenomena extensively and developed particular simulation tools and experimental techniques. A series of experiments to directly compare measurements made under multipactor and breakdown conditions has been initiated with the objective to crosscheck and compare the physics, simulation tools and measurement techniques.

  16. Social Learning in a Human Society: An Experimental Study

    Hamdi, Maziyar; Solman, Grayden; Kingstone, Alan; Krishnamurthy, Vikram


    This paper presents an experimental study to investigate the learning and decision making behavior of individuals in a human society. Social learning is used as the mathematical basis for modelling interaction of individuals that aim to perform a perceptual task interactively. A psychology experiment was conducted on a group of undergraduate students at the University of British Columbia to examine whether the decision (action) of one individual affects the decision of the subsequent individu...

  17. Conditional vs. Voluntary Contribution Mechanism – An Experimental Study

    Reischmann, Andreas


    The Conditional Contribution Mechanism for public good provision gives all agents the possibility to condition their contribution on the total level of contribution provided by all agents. In this experimental study the mechanism's performance is compared to the performance of the Voluntary Contribution Mechanism. In an environment with binary contribution and linear valuations subjects play the mechanisms in a repeated setting. The mechanisms are compared in one case of complete informati...

  18. Experimental studies toward the characterization of Inmetro's circulating water channel

    Santos, A. M.; Alho, A. T. P.; Garcia, D. A.; Farias, M. H.; Massari, P. L.; Silva, V. V. S.


    Circulating water channels are facilities which can be used for conducting environmental, metrological and engineering studies. The Brazilian National Institute of Metrology-INMETRO has a water channel of innovative design, and the present work deals with the prior experimental investigation of its hydrodynamics performance. By using the optical technique PIV - Particle Image Velocimetry, under certain conditions, the velocity profile behavior in a region inside the channel was analyzed in order to evaluate the scope of applicability of such bench.

  19. Respecifying lab ethnography an ethnomethodological study of experimental physics

    Sormani, Philippe


    Respecifying Lab Ethnography delivers the first ethnomethodological study of current experimental physics in action, describing the disciplinary orientation of lab work and exploring the discipline in its social order, formal stringency and skilful performance - in situ and in vivo. In bringing together two major strands of ethnomethodological inquiry, reflexive ethnography and video analysis, which have hitherto existed in parallel, Respecifying Lab Ethnography introduces a practice-based video analysis. In doing so, the book recasts conventional distinctions to shed fresh light on methodolog

  20. Composition of intraocular foreign bodies: experimental study of ultrasonographic presentation

    Costa, Márcio Augusto Nogueira [UNIFESP; Garcia,Patrícia Novita; Barroso, Letícia Fernandes [UNIFESP; Ferreira, Marco Antonio; Okuda, Érika Araki [UNIFESP; Allemann,Norma


    PURPOSE: To investigate the reliability of ultrasound in determining the size and identify the sonographic features and artifacts generated by intraocular foreign bodies of different materials. METHODS: Experimental study using 36 enucleated porcine eyes. Fragments of nine different compositions (wood, glass, plastic, cardboard, iron, aluminum, lead, powder and concrete) and similar dimensions (4 mm) were implanted via scleral incision into the vitreous cavity of 36 porcine eyes, four eyes we...

  1. Experimental study on the pathogenesis of epithelial tumors (VI report)

    Fujiki, Hirota; Ichikawa, Koichi; Yamagiwa, Katsusaburo; Maruyama, Koshichiro; Lee, Kunsei; Fukuda,Tamotsu; Kinoshita, Riojun; Kashiwagi, Masatoshi; Ogawa, Juntaro


    The concept of cancer and inflammation has a long history. Virchow's irritation theory based on human cancer engendered the essential role of inflammation in carcinogenesis. Drs. Yamagiwa and Ichikawa first published a comprehensive paper entitled “Experimental study on the pathogenesis of epithelial tumors” (I report) in 1915 in German, and went on to publish five more reports (1915–1924) under the same title. They succeeded in demonstrating that inflammation is an important carcinogenic fac...

  2. Experimental Study of a Membrane Antenna Surface Adaptive Control System

    Fang, H.; Quijano, U.; Bach, V.; Hill, J.; Wang, K. W.


    Due to their ultra lightweight and high packaging efficiency, membrane reflectors are getting more and more attentions for mission architectures that need extremely large inspace deployable antennas. However how to maintain the surface shape of a membrane reflector to the instrument precision requirements is a very challenging problem. This experimental study investigated using PVDF membrane piezoelectric material as actuators to control the surface figures of membrane reflectors. The feasibility of this approach is demonstrated by several sets of test results.

  3. Gender and Diabetes Mellitus Relevance on Outcomes of Coronary Artery Bypass Grafting. A Retrospective Study

    Sergiu C. BATÂR


    Full Text Available Purpose: For the group of patients with coronary artery disease (CAD, referred to coronary artery bypass surgery, we sought to asses the relevance of gender and presence of Diabetes Mellitus upon survival rates, within the first 3 years after surgery. Methods: At “Nicolae Stancioiu” Heart Institute, a number of 110 patients were followed up from September 2003 to February 2008, for the following events: ischemia, restenosis, atrial fibrillation, ventricular arrhythmias, heart failure, other events and complications. Ages, gender, presence of Diabetes Mellitus were noted. For the diabetic/non-diabetic (45 diabetic, 65 non-diabetic groups and male/female groups (27 female, 83 male, we applied in the SPSS program the Logrank and Wilcoxon tests, for quantifying the differences in the survival rates between the groups. Results: No significant differences were found in the survival rates between the groups (diabetic/non-diabetic Logrank test, p=0.71, Wilcoxon test, p=0.86; female/male Logrank test, p=0.7, Wilcoxon test, p=0.95. Also for the subgroup of patients which had in-graft restenosis (46 patients no significant differences were found between the diabetic/non-diabetic (Logrank test, p=0.36 and gender groups (Logrank test, p=0.4. Mean age for the whole group is 59.2 (61.9 for female and 58.3 for male. Conclusion: Diabetes Mellitus or sex is not significant factors for lower survival rates, in the first 3 years after coronary artery bypass.

  4. An analytical and numerical study of Galton-Watson branching processes relevant to population dynamics

    Jang, Sa-Han

    Galton-Watson branching processes of relevance to human population dynamics are the subject of this thesis. We begin with an historical survey of the invention of the invention of this model in the middle of the 19th century, for the purpose of modelling the extinction of unusual surnames in France and Britain. We then review the principal developments and refinements of this model, and their applications to a wide variety of problems in biology and physics. Next, we discuss in detail the case where the probability generating function for a Galton-Watson branching process is a geometric series, which can be summed in closed form to yield a fractional linear generating function that can be iterated indefinitely in closed form. We then describe the matrix method of Keyfitz and Tyree, and use it to determine how large a matrix must be chosen to model accurately a Galton-Watson branching process for a very large number of generations, of the order of hundreds or even thousands. Finally, we show that any attempt to explain the recent evidence for the existence thousands of generations ago of a 'mitochondrial Eve' and a 'Y-chromosomal Adam' in terms of a the standard Galton-Watson branching process, or indeed any statistical model that assumes equality of probabilities of passing one's genes to one's descendents in later generations, is unlikely to be successful. We explain that such models take no account of the advantages that the descendents of the most successful individuals in earlier generations enjoy over their contemporaries, which must play a key role in human evolution.

  5. [Observational studies in the era of evidence based medicine: short review on their relevance, taxonomy and designs].

    Fronteira, Ines


    In this review of the literature, we distinguish between experimental and observational studies, highlighting the importance that the later have gained in the era of evidence-based medicine. We further analyze the value of observational studies in light of experimental studies. We present a taxonomy for observational studies based on units of observation and measurement (cross-sectional or longitudinal). We distinguish between descriptive studies and analytical studies. Then, and given its specificity, we define and present a classification for ecological studies. We define and consider the advantages and disadvantages of cross-sectional, case control and cohort studies. We analyze the strength of the evidence given by each study design. We finished by examining what should guide the choice of a study design.


    LEE Qi-tao; XUE Lei-ping; HE You-sheng


    An investigation of the ventilated supercavitation for a supercavitating vehicle pitching up and down in the supercavity was carried out in a high-speed water tunnel. The emphasis is laid on the understanding of the interaction of the vehicle aft body with the cavity boundary. The flow characteristics were measured and the stability of supercaviting flow with different pitching frequencies and amplitudes was analyzed. In particular, the objectives of this study are to understand the effect of the impact upon the cavity distortion, and to quantify the impact process by investigating the evolution of the pressure inside the cavity and then the loads on the vehicle during the pitching motion. It is also shown that the evolution of the pressure detected in different,as inside the supercavity, is coherent and uniform during the periods of the pitching motion. This study is of direct relevance to reliable and accurate prediction of hydrodynamic loads associated with the slamming and impact on supercavitating vehicles.

  7. Directing experimental biology: a case study in mitochondrial biogenesis.

    Hibbs, Matthew A; Myers, Chad L; Huttenhower, Curtis; Hess, David C; Li, Kai; Caudy, Amy A; Troyanskaya, Olga G


    Computational approaches have promised to organize collections of functional genomics data into testable predictions of gene and protein involvement in biological processes and pathways. However, few such predictions have been experimentally validated on a large scale, leaving many bioinformatic methods unproven and underutilized in the biology community. Further, it remains unclear what biological concerns should be taken into account when using computational methods to drive real-world experimental efforts. To investigate these concerns and to establish the utility of computational predictions of gene function, we experimentally tested hundreds of predictions generated from an ensemble of three complementary methods for the process of mitochondrial organization and biogenesis in Saccharomyces cerevisiae. The biological data with respect to the mitochondria are presented in a companion manuscript published in PLoS Genetics (doi:10.1371/journal.pgen.1000407). Here we analyze and explore the results of this study that are broadly applicable for computationalists applying gene function prediction techniques, including a new experimental comparison with 48 genes representing the genomic background. Our study leads to several conclusions that are important to consider when driving laboratory investigations using computational prediction approaches. While most genes in yeast are already known to participate in at least one biological process, we confirm that genes with known functions can still be strong candidates for annotation of additional gene functions. We find that different analysis techniques and different underlying data can both greatly affect the types of functional predictions produced by computational methods. This diversity allows an ensemble of techniques to substantially broaden the biological scope and breadth of predictions. We also find that performing prediction and validation steps iteratively allows us to more completely characterize a biological

  8. Directing experimental biology: a case study in mitochondrial biogenesis.

    Matthew A Hibbs


    Full Text Available Computational approaches have promised to organize collections of functional genomics data into testable predictions of gene and protein involvement in biological processes and pathways. However, few such predictions have been experimentally validated on a large scale, leaving many bioinformatic methods unproven and underutilized in the biology community. Further, it remains unclear what biological concerns should be taken into account when using computational methods to drive real-world experimental efforts. To investigate these concerns and to establish the utility of computational predictions of gene function, we experimentally tested hundreds of predictions generated from an ensemble of three complementary methods for the process of mitochondrial organization and biogenesis in Saccharomyces cerevisiae. The biological data with respect to the mitochondria are presented in a companion manuscript published in PLoS Genetics (doi:10.1371/journal.pgen.1000407. Here we analyze and explore the results of this study that are broadly applicable for computationalists applying gene function prediction techniques, including a new experimental comparison with 48 genes representing the genomic background. Our study leads to several conclusions that are important to consider when driving laboratory investigations using computational prediction approaches. While most genes in yeast are already known to participate in at least one biological process, we confirm that genes with known functions can still be strong candidates for annotation of additional gene functions. We find that different analysis techniques and different underlying data can both greatly affect the types of functional predictions produced by computational methods. This diversity allows an ensemble of techniques to substantially broaden the biological scope and breadth of predictions. We also find that performing prediction and validation steps iteratively allows us to more completely

  9. Analytical and experimental studies of wakes behind circularly capped bubbles

    Bessler, W. F.

    The wakes behind circularly capped bubbles are examined by means of an experimental and analytical study. A single two-inch diameter bubble is injected into a six by three foot fluid column, one half inch thick, producing an essentially two-dimensional flow. Aspirin powder placed in the fluid column just prior to bubble release highlights the structure of the flow field before dissolving. High speed film and sequenced photographs are taken to document the observed results. Pressure-time measurements are made with sensitive capacitive transducers mounted in the rear column wall and are synchronized with photographs using a high speed clock. Experimental fluids, prepared by mixing water and glycerine in varying proportions, are used to study the effects of viscosity on bubble shape and wake structure. Testing is performed over a range of Reynolds numbers from 14 to 29,655 which includes the transition from circularly capped to ellipsoidal bubble shape. Experimental data is reduced and summarized in convenient dimensionless form to permit comparison with analytical predictions.

  10. Numerical and experimental study of an Archimedean Screw Generator

    Dellinger, G.; Garambois, P.-A.; Dufresne, M.; Terfous, A.; Vazquez, J.; Ghenaim, A.


    Finding new, safe and renewable energy is becoming more and more of a priority with global warming. One solution that is gaining popularity is the Archimedean Screw Generator (ASG). This kind of hydroelectric plant allows transforming potential energy of a fluid into mechanical energy and is convenient for low-head hydraulic sites. As it is a new and growing technology, there are few references dealing with their design and performance optimization. The present contribution proposes to investigate experimentally and numerically the ASG performances. The experimental study is performed for various flow conditions and a laboratory scale screw device installed at the fluid mechanics laboratory of the INSA of Strasbourg. The first results show that the screw efficiencies are higher than 80% for various hydraulic conditions. In order to study the structure of 3D turbulent flows and energy losses in a screw, the 3D Navier Stokes equations are solved with the k-w SST turbulence model. The exact geometry of the laboratory-scale screw was used in these simulations. Interestingly, the modeled values of efficiency are in fairly good agreement with experimental results while any friction coefficient is involved.

  11. Experimental study and numerical simulation of evacuation from a dormitory

    Lei, Wenjun; Li, Angui; Gao, Ran; Zhou, Ning; Mei, Sen; Tian, Zhenguo


    The evacuation process of students from a dormitory is investigated by both experiment and modeling. We investigate the video record of pedestrian movement in a dormitory, and find some typical characteristics of evacuation, including continuous pedestrian flow, mass behavior and so on. Based on the experimental observation, we found that simulation results considering pre-movement time are closer to the experimental results. With the model considering pre-movement time, we simulate the evacuation process and compare the simulation results with the experimental results, and find that they agree with each other closely. The crowd massing phenomenon is conducted in this paper. It is found that different crowd massing phenomena will emerge due to different desired velocities. The crowd massing phenomenon could be more serious with the increase of the desired velocity. In this study, we also found the faster-is-slower effect. When the positive effect produced by increasing the desired velocity is not sufficient for making up for its negative effect, the phenomenon of the greater the desired velocity the longer the time required for evacuation will emerge. From the video record, it can be observed that the mass behavior is obvious during the evacuation process. And the mass phenomenon could also be found in simulation. The results obtained from our study are also suitable to all these buildings in which both living and resting areas occupy the majority space, such as dormitories, residential buildings, hotels (restaurants) and so on.

  12. Combustion behaviour of pulverised wood - Numerical and experimental studies

    Lixin Tao [TPS Termiska Processer AB, Nykoeping (Sweden)


    This report presents the experimental results achieved in an on-going project financed by STEM (Energimyndigheten) within the research program 'Gasification and combustion of solid fuels', during the first phase of the project (2001-03-05 to 2002-03-05). The project is a collaboration project between LTH and TPS on combined numerical modelling/experimental investigation on combustion of pulverised wood. Particularly TPS carry out the experimental investigation in a laboratory vertical furnace. During the project, the experimental rig has been developed. The experimental furnace has an inner diameter of 0.25 m and a height of 4 m. A pulverised wood flame is established using an axial burner that is installed on the top of the furnace. Experimental study on a selected pulverised wood with determined size distribution and anisotropy character has been carried out in this furnace. During the experiment, the wall temperatures of the furnace were continuously measured using 8 thermocouples of type K that are installed on the wall with a spacing about 0.5 m. The gas temperatures in the furnace were monitored using 5 fixed suction pyrometers that are placed along the centre of the furnace. At the bottom of the furnace, a fixed gas-sampling probe was installed. The flue gas concentrations were continuously monitored with on-line gas analysers. The extent of combustion was measured through the analysis of sampled gaseous products and condensable solid products. A movable liquid quench probe was used to carry out the gas and solid sampling through a number of sampling holes that are opened along the furnace wall. The quench liquor used is an alkaline water solution containing a small amount of a detergent to dissolve HCN and tar. The quench liquor and solid samples were separated and collected in a knockout pot. The gas was filtered and passed through two bubblers with acidic solution to collect NH{sub 3}. The gas concentrations were then analysed with on-line gas

  13. Technological issues and experimental design of gene association studies.

    Distefano, Johanna K; Taverna, Darin M


    Genome-wide association studies (GWAS), in which thousands of single-nucleotide polymorphisms (SNPs) spanning the genome are genotyped in individuals who are phenotypically well characterized, -currently represent the most popular strategy for identifying gene regions associated with common -diseases and related quantitative traits. Improvements in technology and throughput capability, development of powerful statistical tools, and more widespread acceptance of pooling-based genotyping approaches have led to greater utilization of GWAS in human genetics research. However, important considerations for optimal experimental design, including selection of the most appropriate genotyping platform, can enhance the utility of the approach even further. This chapter reviews experimental and technological issues that may affect the success of GWAS findings and proposes strategies for developing the most comprehensive, logical, and cost-effective approaches for genotyping given the population of interest.

  14. Experimental Study on Plasma Surface Treatment of Capacitors Film

    Ling, Dai; Ting, Yin; Fuchang, Lin; Fei, Yan

    Plasma surface treatment is an optional way to change the electrical performance of the film capacitors used widely in pulse power application. This paper presents the experimental study of glow discharge plasma treatment to polyphenylene sulfide (PPS) film. By using infrared spectra and scanning electron microscope (SEM), the chemical component and microstructure of material surface has detected to be changed with different treatment strength and various discharge gas. After treatment, the film surface tends to be rougher and some sorts of polar radicals or groups found to be introduced. But there is no obvious change of the electrical strength of the film. At last, theoretical analysis has been carried out with polypropylene film experimental treatment results in author's former work.

  15. Experimental and theoretical study of metal combustion in oxygen flows

    El-Rabii, Hazem; Muller, Maryse


    The effects of oxygen flow speed and pressure on the iron and mild steel combustion are investigated experimentally and theoretically. The studied specimens are vertical cylindrical rods subjected to an axial oxygen flow and ignited at the upper end by laser irradiation. Three main stages of the combustion process have been identified experimentally: (1) Induction period, during which the rod is heated until an intensive metal oxidation begins at its upper end; (2) Static combustion, during which a laminar liquid "cap" slowly grows on the upper rod end; and, after the liquid cap detachment from the sample, (3) Dynamic combustion, which is characterized by a rapid metal consumption and turbulent liquid motions. An analytical description of these stages is given. In particular, a model of the dynamic combustion is constructed based on the turbulent oxygen transport through the liquid metal-oxide flow. This model yields a simple expression for the fraction of metal burned in the process, and allows one to calcul...

  16. An experimental study on recovering heat from domestic drain water

    Ramadan, Mohamad; Al Shaer, Ali; Haddad, Ahmad; Khaled, Mahmoud


    This paper concerns an experimental study on a system of heat recovery applied to domestic drain water pipes. The concept suggested consists of using the heat still present in the drain water as a preheating/heating source to the cold water supply of the building. To proceed, an appropriate experimental setup is developed and a coil heat exchanger is used as heat transfer device in the recovery system. Several scenarios are simulated and corresponding parameters are recorded and analyzed. It was shown that the suggested recovery concept can considerably preheat the cold water supply and then decrease the energy consumption. Particularly, up to 8.6 kW of heat were recovered when the cold water supply is initially at 3 °C.

  17. Experimental Studies on Combustion Characteristics of Mixed Municipal Solid Waste

    Fan Jiang; Zhonggang Pan; Shi Liu; Haigang Wang


    In our country, municipal solid wastes (MSW) are always burnt in their original forms and only a few pretreatments are taken. Therefore it is vital to study the combustion characteristics of mixed waste. In this paper,thermogravimetric analysis and a lab scale fluidized bed facility were used as experimental means. The data in two different experimental systems were introduced and compared. It took MSW 3~3.5 rain to burn out in FB, but in thermogravimetric analyzer, the time is 20~25 min. It can be concluded that, in general, the behavior of a mixture of waste in TGA can be expressed by simple combination of individual components of the waste mixtures.Only minor deviations from the rule were observed. Yet, in Fluidized Bed, it was found that, for some mixtures,there was interference among the components during fluidized bed combustion.

  18. Experimental study of high temperature particle dropping in coolant liquid

    LI Tianshu; YANG Yanhua; LI Xiaoyan; HU Zhihua


    A series of experiments of the premixing stage of fuel-coolant interactions (FCI), namely the particles falling into water, were carried out. The force on the particles during the course of falling has been studied. The dropping character of hot particle was influenced by three main parameters, i.e., particle temperature, particle diameter and coolant subcooling that varied over a wide range. A high-speed camera recorded the falling speed of the particle and the moving curves were obtained. The experimental results showed that for the film boiling on the surface of particle and water, the temperature increase of either particle or coolant would slow down the particle falling velocity. The falling velocity of particle in small diameter is lower than that of the bigger particle. The present work can provide an experimental foundation for further investigation of high-speed transient evaporation heat transfer.

  19. Experimental study of effect of stenosis geometry on flow parameters

    Veselý Ondřej


    Full Text Available A stenosis is a narrowing in a tubular organ or structure. In medicine, vessel stenosis poses health risks for people. In this work, experimental investigations of pressure loss coefficient for varying stenosis eccentricity and shape were performed. Five models of different geometry were studied; all models were stenosis of 75 % area reduction. The flow conditions approximate physiological flow. The measuring range of Reynolds number was from 130 to 2730, measured values of pressure loss coefficient were from 12 to 20. The steady experimental results indicated that static pressure loss coefficient is affected by the shape of stenosis, but it was affected more significantly by the eccentricity. Visualization experiments have been performed in Polycarbonate models.


    I. V. Kudriavtsev


    Full Text Available Abstract. This review is focused on analysis of currently used flow cytometric methods designed foridentifying apoptotic cells in various invertebrate and vertebrate species. Apoptosis can be characterized by stage-specific morphological and biochemical changes that are typical to all kinds of eukaryotic cells. In this article, we consider different techniques of apoptosis detection based on assessment of cellular morphology and plasma membrane alterations, activation of intracellular enzymes and components of a caspase cascade, as well as DNA fragmentation and failure of mitochondrial transmembrane potential, as assessed in various animal groups. Apoptosis recognized as a key mechanism aiming at maintenance of cellular homeostasis in multicellular organisms, and such investigations represent a necessary component of fundamental and applied studies in diverse fields of experimental biology and immunology. A broad spectrum of apoptosis markers isused, and the preference is given to optimal approaches, as determined by experimental tasks, and technical opportunities of the laboratory.

  1. Experimental and modeling study of the oxidation of xylenes

    Battin-Leclerc, F; Glaude, P A; Belmekki, N; Battin-Leclerc, Fr\\'{e}d\\'{e}rique; Bounaceur, Roda; Glaude, Pierre-Alexandre; Belmekki, Najib


    This paper describes an experimental and modeling study of the oxidation of the three isomers of xylene (ortho-, meta- and para-xylenes). For each compound, ignition delay times of hydrocarbon-oxygen-argon mixtures with fuel equivalence ratios from 0.5 to 2 were measured behind reflected shock waves for temperatures from 1330 to 1800 K and pressures from 6.7 to 9 bar. The results show a similar reactivity for the three isomers. A detailed kinetic mechanism has been proposed, which reproduces our experimental results, as well as some literature data obtained in a plug flow reactor at 1155 K showing a clear difference of reactivity between the three isomers of xylene. The main reaction paths have been determined by sensitivity and flux analyses and have allowed the differences of reactivity to be explained.

  2. New experimental studies of the production of 44Ti

    Robertson, Daniel; Collon, Philippe; Goerres, Joachim; Wiescher, Michael; Becker, Hans Werner


    The main production reaction of 44Ti observed in core collapse supernovae is the 40Ca(α,γ)44Ti reaction. A number of different experimental studies have been performed over the last years to determine the stellar reaction rate. These measurements were based on in-beam gamma spectroscopy techniques, accelerator mass spectrometer (AMS) techniques, and inverse reaction techniques with a recoil separator for separating and detecting the reaction products. The experimental results showed drastic differences. New experiments have been performed at the DTL Bochum and at the NSL Notre Dame using gamma spectroscopy and AMS techniques, respectively to investigate the reaction and the present discrepancies in the predictions. The results of the experiments will be presented and the impact on the reaction rate will be discussed.

  3. Experimental and theoretical studies on visible light attenuation in water

    Simpson, A; Cho, H J; Liu, H


    In this study we describe lab experiments on determining the above water reflectance Rrs coefficient, and the water attenuation coefficient Kd for fresh water. Different types of screens (totally absorbent, gray, etc.) were submerged in water (0-0.6 m) and illuminated from outside. The spectral density of the water leaving radiance was measured for different depths. The results were ran by a code which took into account the geometry of the incident irradiation, the geometry of the screen under water, and boundary conditions at the water surface provided by the radiation transfer theory. From the experimental data and our model we obtain the spectral distribution of the attenuation coefficient for fresh water and compared it with other data in literature. These experiments, performed in the Nonlinear Wave Lab at ERAU# represent just a preliminary calibration of the experimental protocol. More tests with water of different degrees of turbidity, and possibly wave filed at the water surface are in progress and wi...

  4. [Morphological manifestations of systemic atherosclerosis found in fundus (experimental study)].

    Budzinskaia, M V; Fedorov, A A; Pliukhova, A A; Voevodina, T M; Balatskaia, N V


    Results of angiography and morphology of 32 eyes (16 chinchilla rabbits) with experimental atherosclerosis are presented. N.N. Anichkov and S.S. Khalatova experimental hypercholesterolemia model (1912) was used. The animals were divided into the following groups: initial and advanced atherosclerosis, control group, follow-up 3 and 6 months. After 3 months progressive reduction of perfused retinal vessels and early degenerative changes of neurons and photoreceptors were found. In 6 months these changes became more significant and generalized. Due to ongoing small vessel reduction blood flow went to the major vessels and changed its distribution followed by ischemia of adjacent retina. No changes in choriocapillary layer and retinal pigment epithelium were found in any of groups studied.

  5. Design and Experimental Study on Spinning Solid Rocket Motor

    Xue, Heng; Jiang, Chunlan; Wang, Zaicheng

    The study on spinning solid rocket motor (SRM) which used as power plant of twice throwing structure of aerial submunition was introduced. This kind of SRM which with the structure of tangential multi-nozzle consists of a combustion chamber, propellant charge, 4 tangential nozzles, ignition device, etc. Grain design, structure design and prediction of interior ballistic performance were described, and problem which need mainly considered in design were analyzed comprehensively. Finally, in order to research working performance of the SRM, measure pressure-time curve and its speed, static test and dynamic test were conducted respectively. And then calculated values and experimental data were compared and analyzed. The results indicate that the designed motor operates normally, and the stable performance of interior ballistic meet demands. And experimental results have the guidance meaning for the pre-research design of SRM.

  6. Electrochemistry of chlorogenic acid: experimental and theoretical studies

    Namazian, Mansoor [Department of Chemistry, Yazd University, P.O. Box 89195-741, Yazd (Iran, Islamic Republic of)]. E-mail:; Zare, Hamid R. [Department of Chemistry, Yazd University, P.O. Box 89195-741, Yazd (Iran, Islamic Republic of)


    Cyclic voltammetry, chronoamperometry and rotating disk electrode voltammetry as well as quantum chemical methods, are used for electrochemical study of chlorogenic acid, as an important biological molecule. The standard formal potential, diffusion coefficient, and heterogeneous electron transfer rate constant of chlorogenic acid in aqueous solution are investigated. Acidic dissociation constant of chlorogenic acid is also obtained. Quantum mechanical calculations on oxidation of chlorogenic acid in aqueous solution, using density functional theory are presented. The change of Gibbs free energy and entropy of oxidation of chlorogenic acid are calculated using thermochemistry calculations. The calculations in aqueous solution are carried out with the use of polarizable continuum solvation method. Theoretical standard electrode potential of chlorogenic acid is achieved to be 0.580 V versus standard calomel electrode (SCE) which is in agreement with the experimental value of 0.617 V obtained experimentally in this work. The difference is consistent with the values we previously reported for other quinone derivatives.

  7. Experimental Study of Sediment Incipience Under Complex Flows

    LIU Chunrong; DENG Liying; HUANG Zhenhua; HUHE Aode


    Sediment incipience under flows passing a backward-facing step was studied. A series of experiments were conducted to measure scouring depth, probability of sediment incipience, and instantaneous flow velocity field downstream of a backward-facing step. Instantaneous flow velocity fields were measured by using Particle Image Velocimetry (PIV), and an image processing method for determining probability of sediment incipience was employed to analyze the experimental data.The experimental results showed that the probability of sediment incipience was the highest near the reattachment point, even though the near-wall instantaneous flow velocity and the Reynolds stress were both much higher further downstream of the backward-facing step. The possible mechanisms are discussed for the sediment incipience near the reattachment point.

  8. Experimental study of critical flow of water at supercritical pressure

    Yuzhou CHEN; Chunsheng YANG; Shuming ZHANG; Minfu ZHAO; Kaiwen DU; Xu CHENG


    Experimental studies of the critical flow of water were conducted under steady-state conditions with a nozzle 1.41mm in diameter and 4.35 mm in length, covering the inlet pressure range of 22.1-26.8 MPa and inlet temperature range of 38^74°C. The parametric trend of the flow rate was investigated, and the experimental data were compared with the predictions of the homogeneous equilibrium model, the Bernoulli correlation, and the models used in the reactor safety analysis code RELAP5/ MOD3.3. It is concluded that in the near or beyond pseudo-critical region, thermal-dynamic equilibrium is dominant, and at a lower temperature, choking does not occur. The onset of the choking condition is not predicted reasonably by the RELAP5 code.

  9. Experimental study of hydronic panels system and its environment

    Diaz, Nestor Fonseca [University of Liege Belgium, Thermodynamics Laboratory, Campus du Sart Tilman, Bat: B49 - P33, B-4000 Liege (Belgium); Universidad Tecnologica de Pereira, Facultad de Ingenieria Mecanica (Colombia)


    An experimental analysis of hydronic cooling or heating ceiling panels coupled to the building is present in this investigation as a part of the commissioning study of this system. Two test chambers are adapted in a way to reproduce the interaction of the system to the building (windows, internal thermal loads distribution, building structure and ventilation). A series of experimental tests were performed in which the main objective is to observe the influence of parameters such as the water mass flow rate, supply water temperature, thermal load distribution, window and ventilation system effects on the hydronic ceiling capacity and comfort conditions. Test results show that the influence of asymmetric surfaces temperatures inside the room, especially the window effect is not negligible. Then, it is clear that the cooling hydronic ceiling must be evaluated coupled to the building systems and structure. (author)

  10. Experimental study of hydronic panels system and its environment

    Fonseca Diaz, Nestor, E-mail: [University of Liege Belgium, Thermodynamics Laboratory, Campus du Sart Tilman, Bat: B49 - P33, B-4000 Liege (Belgium); Universidad Tecnologica de Pereira, Facultad de Ingenieria Mecanica (Colombia)


    An experimental analysis of hydronic cooling or heating ceiling panels coupled to the building is present in this investigation as a part of the commissioning study of this system. Two test chambers are adapted in a way to reproduce the interaction of the system to the building (windows, internal thermal loads distribution, building structure and ventilation). A series of experimental tests were performed in which the main objective is to observe the influence of parameters such as the water mass flow rate, supply water temperature, thermal load distribution, window and ventilation system effects on the hydronic ceiling capacity and comfort conditions. Test results show that the influence of asymmetric surfaces temperatures inside the room, especially the window effect is not negligible. Then, it is clear that the cooling hydronic ceiling must be evaluated coupled to the building systems and structure.

  11. To Split or to Unify?—A Comparative Study on Functional Equivalence Translation Theory and Relevance Translation Theory

    刘静; 孔燕


      Functional equivalence, a focus in the translation studies, has been bombarded with numerous criticisms. Mean⁃while, relevance translation theory, proposed by Ernst-August Gutt, offers a united theoretical framework for translation stud⁃ies. The development of the translation theories does not rely on the appearance of a brand-new theory, but on the successful connection among various theories. To split or to unify, it is a question and it will direct the further development of transla⁃tion studies. Analyzing the similarities and differences between these two theories, the author are striving for a unity of them and striking a better way to approach translation studies.

  12. A study on the relevance and influence of the existing regulation and risk informed/performance based regulation

    Cheong, B. J.; Koh, Y. J.; Kim, H. S.; Koh, S. H.; Kang, D. H.; Kang, T. W. [Cheju National Univ., Jeju (Korea, Republic of)


    The goal of this study is to estimate the Relevance and Influence of the Existing Regulation and the RI-PBR to the institutionalization of the regulatory system. This study reviews the current regulatory system and the status of the RI-PBR implementation of the US NRC and Korea based upon SECY Papers, Risk Informed Regulation Implementation Plan (RIRIP) of the US NRC and other domestic studies. Also the recent trends of the individual technologies regarding the RI-PBR and RIA are summarized.

  13. Implant stability during initiation and resolution of experimental periimplantitis: an experimental study in the dog.

    Sennerby, Lars; Persson, Leif G; Berglundh, Tord; Wennerberg, Ann; Lindhe, Jan


    Histologic studies have demonstrated the possibility to reestablish direct bone-implant contacts after ligature-induced periimplantitis. The influence of the reosseointegration on the stability of implants is not known. The aim of the present investigation was to study bone tissue and associated implant stability alterations that occurred during induction and resolution of periimplantitis using resonance frequency analysis (RFA), radiography, and histology. Three implants with smooth (turned) or roughened (SLA) surfaces were placed in each side of the edentulous mandible of four dogs. Experimental periimplantitis was induced for 3 months. Five weeks later, the animals were treated with antibiotics and surgical therapy and were followed for another 6 months. Periapical radiographs and RFA were used to evaluate marginal bone levels and implant stability throughout the study period. After termination, the tissue-implant interface was evaluated by light microscopy in ground sections. There was a linear relationship between radiographic and RFA findings because continuous loss of marginal bone and a decrease in implant stability were observed for both implant surfaces during the periimplantitis period. Antibiotic treatment and surgical therapy resulted in some reosseointegration, which was more marked for the SLA surface. The resonance frequency values corresponded well to the histometric measurements because reosseointegration resulted in an increase in implant stability. The findings from the present study indicate a linear relationship between marginal bone level and resonance frequency value. It is suggested that the RFA technique is sensitive and may be used to detect even a minor change in the level of bone-implant contact.

  14. An Experimental Study for Radiation Nephritis in Rabbits

    Kim, Myung Jae [Seoul National University College of Medicine, Seoul (Korea, Republic of)


    Experimental radiation nephritis was produced in 15 rabbits by X-irradiation. About 2, 000gamma(tissue doses) were given to both kidneys of a rabbit in 5 days. Other tissues and organs except both kidneys were protected with 2 mm thickened lead plates. 5 weeks after the last irradiation, blood pictures, blood pressures, B.U.N., serum creatinine, Ca, Mg, Fe levels and serum erythropoietin activity of the irradiated rabbits were studied. After finishing above studies, rabbits were sacrificed and both kidneys were removed and examined histopathologically. Same laboratory and pathological studies were performed in 6 control rabbits. In this study, the author obtained following results. 1) Both kidneys of rabbits with experimental radiation nephritis showed marked histopathological changes, i.e.: renal tubules showed diffuse cloudy swelling, impacted intraluminal hyaline casts and focal precipitations of lime salts on the tubular epithelium. Diffuse interstitial fatty necrosis and various degrees of fibrotic infiltrations on the interstitium were also seen in association with focal lymphocytic infiltrations. Hyaline degenerations were observed on the glomeruli and small vessels. 2) Experimental radiation nephritis rabbits showed marked lowering in R.B.C. counts, decreased hemoglobin levels, low hematocrit values and leucopenia in comparison with those of control rabbits. (P<0.01). (Table 1 and 2). 3) Mild proteinuria were observed in experimental radiation nephritis in rabbits. 4) The levels of B.U.N. and serum creatinine increased in experimental radiation nephritis. (P<0.01). (Table 1, 3 and 4). 5) The levels of serum Ca and Mg Showed no statistical difference in comparison with those of control rabbits. (P>0.05). (Table 3 and 4). 6) No statistical correlations were observable between the levels of B.U.N. and Hb. values. (gamma=-0. 223). No close correlations (gamma=-0.338) were noticed between the levels of B.U.N. and serum iron levels. 7) Erythropoietin activity (R

  15. Confined High Strength Concrete Columns: An Experimental Study

    Jagannathan Saravanan


    Full Text Available Problem statement: An experimental study on GFRP confined high strength concrete columns has been carried out with a view to evaluate its performances under uni-axial compression in terms of load and deformation capacity. Approach: High strength concrete columns strengthened with different configuration and stiffness of GFRP wraps were tested under axial compression until failure. Their response evaluated at different load levels. Results: The test results clearly indicated GFRP wrapped high strength concrete columns exhibit enhances performance. Conclusion: The study concluded that the three GFRP materials attempted UDC GFRP provided the maximum benefit with respect to load and deformation.

  16. Game theory and experimental games the study of strategic interaction

    Colman, Andrew M


    Game Theory and Experimental Games: The Study of Strategic Interaction is a critical survey of the essential ideas of game theory and the findings of empirical research on strategic interaction. Some experiments using lifelike simulations of familiar kinds of strategic interactions are presented, and applications of game theory to the study of voting, the theory of evolution, and moral philosophy are discussed.Comprised of 13 chapters, this volume begins with an informal definition of game theory and an outline of the types of social situations to which it applies. Games of skill, games of cha

  17. Red emitting NLOphoric 3-styryl coumarins: Experimental and computational studies

    Tathe, Abhinav B.; Sekar, Nagaiyan


    The coumarin molecules are versatile fluorophores and can be modified synthetically to give desired properties. The molecules studied have 4-cyano group as an assistance to original chromophore and imparts a red shift. These coumarins were expected to show good non-linear optical (NLO) properties. The experimental and theoretical methods were employed to determine their NLO properties. Directional components of hyperpolarizabilities were calculated and showed a variation according to the placement of electron pulling groups. Studied molecules show a very high (494-794 times of urea) total first order hyperpolarizability. The NLO properties of the molecules were found to be solvent dependant.

  18. Experimental Study on the WavePiston Wave Energy Converter

    Pecher, Arthur; Kofoed, Jens Peter; Angelelli, E.

    This report presents the results of an experimental study of the power performance of the WavePiston wave energy converter. It focuses mainly on evaluating the power generating capabilities of the device and the effect of the following issues: Scaling ratios PTO loading Wave height and wave period...... dependency Oblique incoming waves Distance between plates During the study, the model supplied by the client, WavePiston, has been rigorously tested as all the anticipated tests have been done thoroughly and during all tests, good quality data has been obtained from all the sensors....

  19. Experimental Study Regarding of Bending Behaviour of Stabilizator Link

    Cofaru, Nicolae; Roman, Lucian; Pascu, Adrian; Oleksik, Valentin


    This paper presents an experimental study of the behavior of anti-roll power link subjected to bending, power link coming from an Opel Astra G. The power link is made of PA66 GF30 polyamide. For this study, there were used a universal testing machine (Instron 5587) and a real-time strain measurement optical system (Aramis). The results showed are those obtained in the case of a compression force of 1,000 [N] namely: major Strain ɛ1, minor strain ɛ2, equivalent von Mises strain, displacement on X axis, displacement on Y axis (compression force direction), displacement on Z axis.

  20. On the proper study design applicable to experimental balneology

    Varga, Csaba


    The simple message of this paper is that it is the high time to reevaluate the strategies and optimize the efforts for investigation of thermal (spa) waters. Several articles trying to clear mode of action of medicinal waters have been published up to now. Almost all studies apply the unproven hypothesis, namely the inorganic ingredients are in close connection with healing effects of bathing. Change of paradigm would be highly necessary in this field taking into consideration the presence of several biologically active organic substances in these waters. A successful design for experimental mechanistic studies is approved.

  1. Experimental Study of Mechanistic Acid Deconstruction of Lignin

    Sturgeon, M.; Kim, S.; Chmely, S. C.; Katahira, R.; Foust, T. D.; Beckham, G. T.


    Lignin is a major component of biomass, which remains highly underutilized in selective biomass conversion strategies to renewable fuels and chemicals. Here we are interested in studying the mechanisms related to the acid deconstruction of lignin with a combined theoretical and experimental approach. Quantum mechanical calculations were employed to elucidate possible deconstruction mechanisms with transition state theory. Model dimers, imitating H, S, and G lignins, were synthesized with the most abundant {beta} - O - 4 linkage in lignin. These compounds were then depolymerized using various acids and at different operating conditions. The deconstruction products were analyzed to complement the QM studies and investigate proposed mechanisms.

  2. On the proper study design applicable to experimental balneology.

    Varga, Csaba


    The simple message of this paper is that it is the high time to reevaluate the strategies and optimize the efforts for investigation of thermal (spa) waters. Several articles trying to clear mode of action of medicinal waters have been published up to now. Almost all studies apply the unproven hypothesis, namely the inorganic ingredients are in close connection with healing effects of bathing. Change of paradigm would be highly necessary in this field taking into consideration the presence of several biologically active organic substances in these waters. A successful design for experimental mechanistic studies is approved.

  3. Experimental and computational studies of electromagnetic cloaking at microwaves

    Wang, Xiaohui

    An invisibility cloak is a device that can hide the target by enclosing it from the incident radiation. This intriguing device has attracted a lot of attention since it was first implemented at a microwave frequency in 2006. However, the problems of existing cloak designs prevent them from being widely applied in practice. In this dissertation, we try to remove or alleviate the three constraints for practical applications imposed by loosy cloaking media, high implementation complexity, and small size of hidden objects compared to the incident wavelength. To facilitate cloaking design and experimental characterization, several devices and relevant techniques for measuring the complex permittivity of dielectric materials at microwave frequencies are developed. In particular, a unique parallel plate waveguide chamber has been set up to automatically map the electromagnetic (EM) field distribution for wave propagation through the resonator arrays and cloaking structures. The total scattering cross section of the cloaking structures was derived based on the measured scattering field by using this apparatus. To overcome the adverse effects of lossy cloaking media, microwave cloaks composed of identical dielectric resonators made of low loss ceramic materials are designed and implemented. The effective permeability dispersion was provided by tailoring dielectric resonator filling fractions. The cloak performances had been verified by full-wave simulation of true multi-resonator structures and experimental measurements of the fabricated prototypes. With the aim to reduce the implementation complexity caused by metamaterials employment for cloaking, we proposed to design 2-D cylindrical cloaks and 3-D spherical cloaks by using multi-layer ordinary dielectric material (epsilon r>1) coating. Genetic algorithm was employed to optimize the dielectric profiles of the cloaking shells to provide the minimum scattering cross sections of the cloaked targets. The designed cloaks can

  4. Relevant indoor ventilation by windows and apertures in tropical climate: a review study

    Aflaki Ardalan


    Full Text Available High temperature and humidity oblige occupants to use mechanical ventilation to regulate indoor temperature in tropical climate. Therefore, energy consumption becomes a challenge facing the designers in primary steps of design. Natural ventilation known as a passive design strategy in buildings is one of the innovative techniques in modern building to reduce operation costs and energy consumption. Although the advantages of natural ventilation are proved by previous studies, few studies have been done on application of openings and apertures designs to maximize indoor air velocity inside the buildings. This study reviews different ventilation methods and techniques which have been applied through openings to identify the most effective architectural elements for adequate ventilation inside the buildings. Comparison of study results shows that building orientation accompanying with apertures size are effective design strategies and techniques to increase indoor air ratio. Finally, the study recommends various form of openings and different form of louvered windows as research gaps for further study.

  5. Manipulation of pain catastrophizing: An experimental study of healthy participants

    Joel E Bialosky


    Full Text Available Joel E Bialosky1*, Adam T Hirsh2,3, Michael E Robinson2,3, Steven Z George1,3*1Department of Physical Therapy; 2Department of Clinical and Health Psychology; 3Center for Pain Research and Behavioral Health, University of Florida, Gainesville, Florida, USAAbstract: Pain catastrophizing is associated with the pain experience; however, causation has not been established. Studies which specifically manipulate catastrophizing are necessary to establish causation. The present study enrolled 100 healthy individuals. Participants were randomly assigned to repeat a positive, neutral, or one of three catastrophizing statements during a cold pressor task (CPT. Outcome measures of pain tolerance and pain intensity were recorded. No change was noted in catastrophizing immediately following the CPT (F(1,84 = 0.10, p = 0.75, partial η2 < 0.01 independent of group assignment (F(4,84 = 0.78, p = 0.54, partial η2 = 0.04. Pain tolerance (F(4 = 0.67, p = 0.62, partial η2 = 0.03 and pain intensity (F(4 = 0.73, p = 0.58, partial η2 = 0.03 did not differ by group. This study suggests catastrophizing may be difficult to manipulate through experimental pain procedures and repetition of specific catastrophizing statements was not sufficient to change levels of catastrophizing. Additionally, pain tolerance and pain intensity did not differ by group assignment. This study has implications for future studies attempting to experimentally manipulate pain catastrophizing.Keywords: pain, catastrophizing, experimental, cold pressor task, pain catastrophizing scale

  6. Spanish Verbs Visualization: A study and scalable experimentation

    Ana García Serrano


    Full Text Available In this paper it is presented a study on verbs in Spanish and it’s potential to display images from the Wikipedia (Wikimedia. It is designed and developed an Information Retrieval model based on linguistic structures of verbs and an environment that allows all subsequent scaling Spanish verbs. Adesse and EuroWordNet are the linguistic resources selected to bring the theoretical basis of the work. In the absence of an adequate corpus with relevant judgments to the problem, it has been recorded by the second author a subset of visual verbs sufficiently representative and enable to further work on this issue. Finally conclusions about visual verbs as well as the obtained results are provided

  7. Linguistically-Relevant Diachronic Study of Cultural Values in Early British Advertising Discourse

    Kochetova, Larisa A.


    Drawing on linguistic data retrieved from early advertisements published in British newspapers between 1788 and 1900, the study seeks to map out a set of values and account for linguistic means used to codify them in the diachronic perspective. For the purposes of the study, the corpus of advertisements from random issues of British newspapers…

  8. The utricular otoliths, lapilli, of teleosts: their morphology and relevance for species identification and systematics studies

    Carlos A. Assis


    Full Text Available The present study describes the general morphology of the utricular otoliths, lapilli, of teleost fishes, proposes a terminology for their parts, identifies their two major morphological types, provides some examples of their use in species identification, and discusses their usefulness in studies of fish phylogeny and systematics.

  9. Reasserting the Relevance of the Social Studies: An Emerging Model for Collaborative Cross-State Research

    Passe, Jeff; Patterson, Nancy


    There is a timely movement afoot to secure the rightful place of social studies as a core part of curriculum at a time when it is increasingly compromised across the nation. The authors present a model that accepts the call to consider the enterprise of social studies research and broaden it to address the needs of the day. They offer a brief…

  10. The relevance of political prestudies for implementation studies of cognitive services in community pharmacies

    Kaae, Susanne; Traulsen, Janine Marie; Søndergaard, Birthe


    BACKGROUND: Studies of cognitive services implementation in the pharmacy sector traditionally focus on individual and/or organizational factors to explain why some pharmacies are successful and others are not. The social and political context of the origins of these services is rarely part...... of the analysis. Researchers and practitioners in the field of pharmacy practice research are increasingly being encouraged to take into account the specific political and societal climate which often plays a defining role in the success or failure of cognitive services implementation in community pharmacies....... OBJECTIVE: The aim of this article is to argue for the inclusion of political pre-studies as part of the study design for implementation studies on reimbursed services in community pharmacy. METHODS: A political pre-study of the Inhaler Technique Assessment Service (ITAS) introduced in Denmark in 2004...

  11. Atypical water lattices and their possible relevance to the amorphous ices: A density functional study

    David J. Anick


    Full Text Available Of the fifteen known crystalline forms of ice, eleven consist of a single topologically connected hydrogen bond network with four H-bonds at every O. The other four, Ices VI–VIII and XV, consist of two topologically connected networks, each with four H-bonds at every O. The networks interpenetrate but do not share H-bonds. This article presents two new periodic water lattice families whose topological connectivity is “atypical”: they consist of many two-dimensional layers that share no H-bonds. Layers are held together only by dispersion forces. Within each layer there are still four H-bonds at each O. Called “Hexagonal Bilayer Water” (HBW and “Pleated Sheet Water” (PSW, they have computed densities of about 1.1 g/mL and 1.3 g/mL respectively, and nearest neighbor O-coordination is 4.5 to 5.5 and 6 to 8 respectively. Using density functional theory (BLYP-D/TZVP, various proton ordered forms of HBW and PSW are optimized and categorized. There are simple pathways connecting Ice-Ih to HBW and HBW to PSW. Their computed properties suggest similarities to the high density and very high density amorphous ices (HDA and VHDA respectively. It is unknown whether HDA, VHDA, and Low Density Amorphous Ice (LDA are fully disordered glasses down to the molecular level, or whether there is some short-range local order. Based on estimated radial distribution functions (RDFs, one proton ordered form of HBW matches HDA best. The idea is explored that HDA could contain islands with this underlying structure, and likewise, that VHDA could contain regions of PSW. A “microlattice model version 1” (MLM1 is presented as a device to compare key experimental data on the amorphous ices with these atypical structures and with a microlattice form of Ice-XI for LDA. Resemblances are found with the amorphs’ RDFs, densities, Raman spectra, and transition behaviors. There is not enough information in the static models to assign either a microlattice structure

  12. Uncovering study abroad: foreignness and its relevance to nurse education and cultural competence.

    Greatrex-White, Sheila


    This paper reports some of the findings from a hermeneutic phenomenological research project designed to uncover the nature of the phenomenon 'study abroad' in the context of Nursing Higher Education in the United Kingdom. The research question asked was 'How is study abroad manifest in the experience of nursing students?' Informed by the philosophy of Martin Heidegger, the analysis of 26 study abroad students' diary accounts uncovered six general structures, or ways for study abroad to be, namely; leaving behind, escape, foreigner, self-discovery, learning and risk. The focus here is on the general structure 'foreigner' and the far-reaching implications this can have in terms of understanding how study abroad comes to be. The relationship between study abroad, positive disturbance and the development of students who are able to recognise diversity across different cultures is discussed. It is suggested that if one of the major aims of nurse higher education is the development of culturally competent practitioners, study abroad is deserving of far greater attention than is currently the case.

  13. Experimental study on fluid flow in arciform clearance

    邵俊鹏; 汤卉; 贾慧娟


    The system damping and dynamic characteristics can be further improved by properly increasing thedamping coefficient ξh. For a special hydraulic damping structure, an arciform damping clearance often used inFCS, a mathematical model has been established for fluid flow using the theory of laminar flow in the clearanceof parallel plates. Analytical calculations are made for fluid flow in the arciform clearance and relational expres-sion is deduced for flow rate along the arciform cleaance height, pressure difference, maximum arciform clear-ance height, the flow rate for the fluid flow in arciform clearance as well, and its simplified formula is obtainedby using the theory of hydrodynamics and the curve - fitting method. This paper consists of two sections: the firstsection focuses on the theoretical analysis by using the simplified mathematical model and the second sectionmainly describes experimental analysis. The simplified formula is corrected with experimental results by consid-erig various boundary conditions of the damping clearance. Experimental results show that this study of arciformdamping clearance is reliable and practical.

  14. Experimental and theoretical study of Rayleigh-Lamb wave propagation

    Rogers, Wayne P.; Datta, Subhendu K.; Ju, T. H.


    Many space structures, such as the Space Station Freedom, contain critical thin-walled components. The structural integrity of thin-walled plates and shells can be monitored effectively using acoustic emission and ultrasonic testing in the Rayleigh-Lamb wave frequency range. A new PVDF piezoelectric sensor has been developed that is well suited to remote, inservice nondestructive evaluation of space structures. In the present study the new sensor was used to investigate Rayleigh-Lamb wave propagation in a plate. The experimental apparatus consisted of a glass plate (2.3 m x 25.4 mm x 5.6 mm) with PVDF sensor (3 mm diam.) mounted at various positions along its length. A steel ball impact served as a simulated acoustic emission source, producing surface waves, shear waves and longitudinal waves with dominant frequencies between 1 kHz and 200 kHz. The experimental time domain wave-forms were compared with theoretical predictions of the wave propagation in the plate. The model uses an analytical solution for the Green's function and the measured response at a single position to predict response at any other position in the plate. Close agreement was found between the experimental and theoretical results.

  15. Nonlocal Regularized Algebraic Reconstruction Techniques for MRI: An Experimental Study

    Xin Li


    Full Text Available We attempt to revitalize researchers' interest in algebraic reconstruction techniques (ART by expanding their capabilities and demonstrating their potential in speeding up the process of MRI acquisition. Using a continuous-to-discrete model, we experimentally study the application of ART into MRI reconstruction which unifies previous nonuniform-fast-Fourier-transform- (NUFFT- based and gridding-based approaches. Under the framework of ART, we advocate the use of nonlocal regularization techniques which are leveraged from our previous research on modeling photographic images. It is experimentally shown that nonlocal regularization ART (NR-ART can often outperform their local counterparts in terms of both subjective and objective qualities of reconstructed images. On one real-world k-space data set, we find that nonlocal regularization can achieve satisfactory reconstruction from as few as one-third of samples. We also address an issue related to image reconstruction from real-world k-space data but overlooked in the open literature: the consistency of reconstructed images across different resolutions. A resolution-consistent extension of NR-ART is developed and shown to effectively suppress the artifacts arising from frequency extrapolation. Both source codes and experimental results of this work are made fully reproducible.

  16. [Persuasive communications and regular blood donation: an experimental study].

    Cunha, Balduino Guedes Fernandes da; Dias, Mardonio Rique


    This study aimed to: investigate yielding to the dependent variable "behavioral intent to become a regular blood donor", verify the impact of such communications on variance in the dependent variable, examine the single contribution of the external independent variable to the Rational Action Theory, and test the fit of the expanded Rational Choice Theory to the target behavior and sample. Only a post-test design and double-blinded procedure were used, randomly picking 405 university students for experimental groups 1 and 2, placebo control, and control only. The results showed: lack of yielding by the experimental groups; considerable percentage variance in the dependent variable explained by the independent variable in the experimental and placebo control groups; and satisfactory and significant correlations for variables in the expanded theory. Absence of yielding for the criterion variable was probably due to the time interval. The positive persuasive strategy accounted for the greatest variance in the dependent variable. Moral obligation showed the greatest impact on participants' intent to perform the behavior. The correlations corroborated the theoretical and methodological validity of the expanded theory.

  17. Temporal evolution of mechanical properties of skeletal tissue regeneration in rabbits. An experimental study

    Mokoko, Didier; Chabrand, Patrick


    Various mathematical models represent the effects of local mechanical environment on the regulation of skeletal regeneration. Their relevance relies on an accurate description of the evolving mechanical properties of the regenerating tissue. The object of this study was to develop an experimental model which made it possible to characterize the temporal evolution of the structural and mechanical properties during unloaded enchondral osteogenesis in the New Zealand rabbit, a standard animal model for studies of osteogenesis and chondrogenesis. A 25mm segment of tibial diaphysis was removed sub-periosteally from rabbits. The defect was repaired by the preserved periosteum. An external fixator was applied to prevent mechanical loading during osteogenesis. The regenerated skeletal tissues were studied by CT scan, histology and mechanical tests. The traction tests between 7 to 21 days post-surgery were done on formaldehyde-fixated tissue allowing to obtain force/displacement curves. The viscoelastic properties of ...

  18. Experimental studies of forensic odontology to aid in the identification process.

    Saxena, Susmita; Sharma, Preeti; Gupta, Nitin


    The importance of dental identification is on the increase year after year. With the passage of time, the role of forensic odontology has increased as very often teeth and dental restorations are the only means of identification. Forensic odontology has played a key role in identification of persons in mass disasters (aviation, earthquakes, Tsunamis), in crime investigations, in ethnic studies, and in identification of decomposed and disfigured bodies like that of drowned persons, fire victims, and victims of motor vehicle accidents. The various methods employed in forensic odontology include tooth prints, radiographs, photographic study, rugoscopy, cheiloscopy and molecular methods. Investigative methods applied in forensic odontology are reasonably reliable, yet the shortcomings must be accounted for to make it a more meaningful and relevant procedure. This paper gives an overview of the various experimental studies to aid in the identification processes, discussing their feasibilities and limitations in day-to-day practice.

  19. Experimental studies of forensic odontology to aid in the identification process

    Susmita Saxena


    Full Text Available The importance of dental identification is on the increase year after year. With the passage of time, the role of forensic odontology has increased as very often teeth and dental restorations are the only means of identification. Forensic odontology has played a key role in identification of persons in mass disasters (aviation, earthquakes, Tsunamis, in crime investigations, in ethnic studies, and in identification of decomposed and disfigured bodies like that of drowned persons, fire victims, and victims of motor vehicle accidents. The various methods employed in forensic odontology include tooth prints, radiographs, photographic study, rugoscopy, cheiloscopy and molecular methods. Investigative methods applied in forensic odontology are reasonably reliable, yet the shortcomings must be accounted for to make it a more meaningful and relevant procedure. This paper gives an overview of the various experimental studies to aid in the identification processes, discussing their feasibilities and limitations in day-to-day practice.

  20. [Experimental study of infectious hepatitis in guinea pigs].

    Asharafova, R A; Tuliaganov, P D; Kasymkhodzhaev, E S


    The authors carried out a comparative study of morphological changes in the liver of guinea-pigs in various times following intraperitoneal administration of the serum taken from a patient with infectious hepatitis (1st group), administration of the serum in combination with the urine (2nd group), administration of the serum in combination with the patient's duodenal juice (3rd group), and administration of the serum in combination with a hepatic antigen prepared of the liver of a healthy guinea-pig (4th group). Observations over the behaviour of the animals and morphological investigations showed a high sensitivity of guinea-pigs to virus-containing materials. The reaction was particularly pronounced in animals which were given the serum taken from a patient with infectious hepatitis in combination with a hepatic antigen, and the microscopic picture of the liver almost similar to that of the patient with Botkin's disease. Moreover, in the course of the study it was found possible to re-inoculate the virus obtained from the guinea-pigs subjected to a combined exposure to the serum from a patient with infectious hepatits and hepatic antigen. Comparing the results of the study on guinea-pigs with those obtained previously in the experimental study of viral hepatitis on white rats (1970), the authors have come to the conclusion that guinea-pigs may be used for modelling and experimental investigation of Botkin's disease.

  1. Thermodynamics of protein-ligand interactions as a reference for computational analysis: how to assess accuracy, reliability and relevance of experimental data.

    Krimmer, Stefan G; Klebe, Gerhard


    For a conscientious interpretation of thermodynamic parameters (Gibbs free energy, enthalpy and entropy) obtained by isothermal titration calorimetry (ITC), it is necessary to first evaluate the experimental setup and conditions at which the data were measured. The data quality must be assessed and the precision and accuracy of the measured parameters must be estimated. This information provides the basis at which level discussion of the data is appropriate, and allows insight into the significance of comparisons with other data. The aim of this article is to provide the reader with basic understanding of the ITC technique and the experimental practices commonly applied, in order to foster an appreciation for how much measured thermodynamic parameters can deviate from ideal, error-free values. Particular attention is paid to the shape of the recorded isotherm (c-value), the influence of the applied buffer used for the reaction (protonation reactions, pH), the chosen experimental settings (temperature), impurities of protein and ligand, sources of systematic errors (solution concentration, solution activity, and device calibration) and to the applied analysis software. Furthermore, we comment on enthalpy-entropy compensation, heat capacities and van't Hoff enthalpies.

  2. Effect of Operating Conditions on CSTR performance: an Experimental Study

    Mohd Danish


    Full Text Available In this work, Saponification reaction of ethyl acetate by sodium hydroxide is studied experimentally in a continuous stirred tank reactor at 1 atmospheric pressure. The aim of this study is to investigate the influence of operating conditions on the conversion and specific rate constant. The parameters considered for analysis are temperature, feed flow rate, residence time, volume of reactor and stirrer rate. The steady state conversion of 0.45 achieved after a period of 30 minutes. Conversion decreases with increase of reactant flow rate due to decrease of residence time. The stirrer rate has a positive effect on the conversion and rate constant. Specific rate constant and conversion increase with temperature within the studied temperature range. Within the range of reactor volume selected for analysis, conversion increases with increase in reactor volume. The results obtained in this study may be helpful in maximizing the conversion of ethyl acetate saponification reaction at industrial scale in a CSTR.

  3. [The Philosophical Relevance of the Study of Schizophrenia. Methodological and Conceptual Issues].

    López-Silva, Pablo


    The study of mental illness involves profound methodological and philosophical debates. This article explores the disciplinary complementarity, particularly, between philosophy of mind, phenomenology, and empirical studies in psychiatry and psychopathology in the context of the understanding of schizophrenia. After clarifying the possible role of these disciplines, it is explored the way in which a certain symptom of schizophrenia (thought insertion) challenges the current phenomenological approach to the relationship between consciousness and self-awareness. Finally, it is concluded that philosophy of mind, phenomenology, and empirical studies in psychiatry and psychopathology should, necessarily, regulate their progress jointly in order to reach plausible conclusions about what we call 'schizophrenia'. Crown Copyright © 2014. Publicado por Elsevier España. All rights reserved.

  4. Experimental pain induces attentional bias that is modified by enhanced motivation: An eye tracking study.

    Sun, Z-K; Wang, J-Y; Luo, F


    In this study, the effects of prior pain experience and motivation on attentional bias towards pain-related information were investigated within two visual-probe tasks via eye movement behaviours. It is hypothesized that pain experience would induce stronger attentional bias and such bias could be suppressed by the motivation to avoid impeding pain. All participants took part in visual-probe tasks with pictures and words as stimuli that are typically used in studies of attentional bias. They were allocated to three groups: no-pain (NP) group, performing tasks without experiencing pain; pain-experience (PE) group, performing the same tasks following painful stimuli; and pain-experience-with-motivation (PEM) group, undergoing the same procedure as PE group with additional instructions about avoiding impeding pain. Eye movements were recorded during the tasks. The eye movement data showed that: (1) participants in the PE group exhibited stronger attention bias towards painful pictures than those in the NP group; (2) the attentional bias towards painful pictures was significantly reduced in the PEM group as compared to the PE group. By contrast, the verbal task failed to find these effects using sensory pain words as stimuli. This study was the first that revealed the impact of acute experimental pain on attentional bias towards pain-related information in healthy individuals through eye tracking. It may provide a possible solution to reduce hypervigilance towards pain-related information by altering the motivational relevance. WHAT DOES THIS STUDY ADD?: (1) This study revealed the impact of experimental pain on attentional bias in healthy individuals; (2) This study may provide a possible approach of altering motivational relevance to control the pain-induced attentional bias towards pain-related information. © 2016 European Pain Federation - EFIC®

  5. Relevance of community structures and neighbourhood characteristics for participation of older adults: a qualitative study.

    Strobl, Ralf; Maier, Werner; Ludyga, Alicja; Mielck, Andreas; Grill, Eva


    Community and neighbourhood structures contribute not only to the health and well-being, but also to the participation of older adults. The degree of participation depends on both the living environment and the individual's personal characteristics, preferences and perception. However, there is still limited empirical evidence on how community and neighbourhood structures are linked to participation and health in the aged population. A qualitative exploratory approach was chosen with a series of problem-centred, semi-structured focus group discussions. Study participants were selected from within the city of Augsburg, Southern Germany, and from two municipalities in surrounding rural districts. The interviews took place in 2013. Structuring content analysis was used to identify key concepts. We conducted 11 focus group discussions with a total of 78 different study participants. The study participants (33 men and 45 women) had a mean age of 74 years (range 65-92 years). Only two study participants lived in an assisted living facility. Of all study participants, 77% lived in urban and 23% in rural areas. We extracted four metacodes ('Usual activities', 'Requirements for participation', 'Barriers to participation' and 'Facilitators for participation') and 15 subcodes. Health and poorly designed infrastructure were mentioned as important barriers to participation, and friendship and neighbourhood cohesion as important facilitators. This qualitative study revealed that poor design and accessibility of municipal infrastructure are major barriers to participation in old age in Germany. Community and neighbourhood structures can be part of the problem but also part of the solution when accessibility and social networks are taken into account.

  6. Critical language and discourse study: their transformative relevance for critical nursing inquiry.

    Boutain, D M


    A pragmatic view of language and a critical study of discourse can advance nursing inquiry toward the study of racism, heterosexism, classism, and health. In critical language inquiry notions about humans, health and illness are seen as constructed in societal discourses. Critical language inquiry challenges nurse researchers to theorize not which research questions to ask, but how to ask research questions that broaden knowledge about the interconnections among language, discourse, health, and society. Critical discourse analysis, as a methodology, can be of significant utility in exploring the relationships among health, discourse, power, and society.

  7. Mahatma Gandhi and Character Education in Non-Violence: Its Relevance in Religious Studies Today

    Damm, Alex


    This essay presents educational principles of Mahatma Gandhi, specifically principles of character education, as a model for strengthening non-violence in students. Its major concern is to show that Gandhi's ideal of non-violent character education is important for university teaching in disciplines including religious studies, and that Gandhi…

  8. How relevant are Hofstede's dimensions for inter-cultural studies? A ...

    Stenden Hotel Management School, Stenden University of Applied Sciences, ... Hofstede tried to solve the “Western bias” in his original VSM ... is examined as a main effect (Type I studies) at the individual .... cultural dimensions in order to test their hypothesis that an ..... Consumer behavior and culture: Consequences.

  9. FMRI study relevant to the Mozart effect: brain areas involved in spatial-temporal reasoning.

    Bodner, M; Muftuler, L T; Nalcioglu, O; Shaw, G L


    Behavioral studies, motivated by columnar cortical model predictions, have given evidence for music causally enhancing spatial-temporal reasoning. A wide range of behavioral experiments showed that listening to a Mozart Sonata (K.448) gave subsequent enhancements. An EEG coherence study gave evidence for a carryover from that Mozart Sonata listening condition to the subsequent spatial-temporal task in specific cortical regions. Here we present fMRI studies comparing cortical blood flow activation by the Mozart Sonata vs. other music. In addition to expected temporal cortex activation, we report dramatic statistically significant differences in activation by the Mozart Sonata (in comparison to Beethoven's Fur Elise and 1930s piano music) in dorsolateral pre-frontal cortex, occipital cortex and cerebellum, all expected to be important for spatial-temporal reasoning. It would be of great interest to explicitly test this expectation. We propose an fMRI study comparing (subject by subject) brain areas activated in music listening conditions and in spatial-temporal tasks.

  10. Diving physiology of seabirds and marine mammals: Relevance, challenges and some solutions for field studies.

    Andrews, Russel D; Enstipp, Manfred R


    To fully understand how diving seabirds and marine mammals balance the potentially conflicting demands of holding their breath while living their lives underwater (and maintaining physiological homeostasis during exercise, feeding, growth, and reproduction), physiological studies must be conducted with animals in their natural environments. The purpose of this article is to review the importance of making physiological measurements on diving animals in field settings, while acknowledging the challenges and highlighting some solutions. The most extreme divers are great candidates for study, especially in a comparative and mechanistic context. However, physiological data are also required of a wide range of species for problems relating to other disciplines, in particular ecology and conservation biology. Physiological data help with understanding and predicting the outcomes of environmental change, and the direct impacts of anthropogenic activities. Methodological approaches that have facilitated the development of field-based diving physiology include the isolated diving hole protocol and the translocation paradigm, and while there are many techniques for remote observation, animal-borne biotelemetry, or "biologging", has been critical. We discuss issues related to the attachment of instruments, the retrieval of data and sensing of physiological variables, while also considering negative impacts of tagging. This is illustrated with examples from a variety of species, and an in-depth look at one of the best studied and most extreme divers, the emperor penguin (Aptenodytes forsteri). With a variety of approaches and high demand for data on the physiology of diving seabirds and marine mammals, the future of field studies is bright.

  11. Azoxymethane-induced rat aberrant crypt foci: Relevance in studying chemoprevention of colon cancer

    Jayadev Raju


    The pathogenesis of colon cancer involves sequential and multistep progression of epithelial cells initiated to a cancerous state with defined precancerous intermediaries.Aberrant crypt foci (ACF) represent the earliest identifiable intermediate precancerous lesions during colon carcinogenesis in both laboratory animals and humans.ACF are easily induced by colon-specific carcinogens in rodents and can be used to learn more about the process of colon carcinogenesis.For over two decades,since its first discovery,azoxymethane(AOM)-induced rodent ACF have served as surrogate biomarkers in the screening of various anticarcinogens and carcinogens.Several dietary constituents and phytochemicals have been tested for their colon cancer chemopreventive efficacy using the ACF system.There has been substantial effort in defining and refining ACF in terms of understanding their molecular make-up,and extensive research in this field is currently in progress.In chemoprevention studies,AOM-induced rat ACF have been very successful as biomarkers,and have provided several standardized analyses of data.There have been several studies that have reported that ACF data do not correlate to actual colon tumor outcome,however,and hence there has been an ambiguity about their role as biomarkers.The scope of this mini-review is to provide valuable insights and limitations of AOM-induced rat ACF as biomarkers in colon cancer chemoprevention studies.The role of the dynamics and biological heterogeneity of ACF is critical in understanding them as biomarkers in chemoprevention studies.

  12. Stability of the Elbow Joint: Relevant Anatomy and Clinical Implications of In Vitro Biomechanical Studies

    J. de Haan (Jeroen); D. Eygendaal (Denise); N.W.L. Schep (Niels); G.J. Kleinrensink (Gert Jan); W.E. Tuinebreijer (Wim); D. den Hartog (Dennis)


    textabstractAbstract: The aim of this literature review is to describe the clinical anatomy of the elbow joint based on information from in vitro biomechanical studies. The clinical consequences of this literature review are described and recommendations are given for the treatment of elbow joint di

  13. Wind‐gust parametrizations at heights relevant for wind energy: a study based on mast observations

    Suomi, I.; Vihma, T.; Gryning, Sven-Erik;


    gustiness conditions were studied using observations from two coastal/archipelago weather masts in the Gulf of Finland (northern Europe) with observation heights between 30 and 143 m. Only moderate and strong wind cases were addressed. Both masts were located over relatively flat terrain but the local...

  14. Mahatma Gandhi and Character Education in Non-Violence: Its Relevance in Religious Studies Today

    Damm, Alex


    This essay presents educational principles of Mahatma Gandhi, specifically principles of character education, as a model for strengthening non-violence in students. Its major concern is to show that Gandhi's ideal of non-violent character education is important for university teaching in disciplines including religious studies, and that Gandhi…

  15. Molecular Cloning and Pharmacology of Porcine 5-Hydroxytryptamine Receptors Relevant to the Study of Antimigraine Drugs

    P.L. Bhalla (Pankaj)


    textabstractAt the beginning of last century, Brodie (1900) described in an extensive study that injection of blood serum causes vasoconstriction and a vagally-mediated reflex resulting in a reversible bradycardia, hypotension and arrest of the respiration, while injection of blood plasma was devoid

  16. Experimental Study of the Subsidence Characteristics of Clayey Loess

    Li Lan; Wang Lanmin


    Presented in this paper are the results of experimental study and analysis of the subsidence characteristics obtained from soil samples with different contents of clay particles though laboratory dynamic triaxial test, Laser particle size analysis, chemical analysis and electronic microscope scanning. By comparison of the obtained data, the following conclusions are drawn out: (1)The stability of the loess varies with different content of clay; (2) The relation between the dynamic shear strength and the clay particles is not monotonous, but parabolic; (3) In the same consolidation ratio, the clayey loess is the weakest subsidence-resistant when the clay particle content is between 16% ~ 17%.

  17. Competition, Income Distribution, and the Middle Class: An Experimental Study

    Bernhard Kittel


    Full Text Available We study the effect of competition on income distribution by means of a two-stage experiment. Heterogeneous endowments are earned in a contest, followed by a surplus-sharing task. The experimental test confirms our initial hypothesis that the existence of a middle class is as effective as institutional hurdles in limiting the power of the less able in order to protect the more able players from being expropriated. Furthermore, majoritarian voting with a middle class involves fewer bargaining impasses than granting veto rights to the more able players and, therefore, is more efficient.

  18. Experimental studies of the transient fluctuation theorem using liquid crystals

    Soma Datta; Arun Roy


    In a thermodynamical process, the dissipation or production of entropy can only be positive or zero, according to the second law of thermodynamics. However, the laws of thermodynamics are applicable to large systems in the thermodynamic limit. Recently a fluctuation theorem, known as the transient fluctuation theorem (TFT), which generalizes the second law of thermodynamics to small systems has been proposed. This theorem has been tested in small systems such as a colloidal particle in an optical trap. We report for the first time an analogous experimental study of TFT in a spatially extended system using liquid crystals.

  19. Designing artificial enzymes from scratch: Experimental study and mesoscale simulation

    Komarov, Pavel V.; Zaborina, Olga E.; Klimova, Tamara P.; Lozinsky, Vladimir I.; Khalatur, Pavel G.; Khokhlov, Alexey R.


    We present a new concept for designing biomimetic analogs of enzymatic proteins; these analogs are based on the synthetic protein-like copolymers. α-Chymotrypsin is used as a prototype of the artificial catalyst. Our experimental study shows that in the course of free radical copolymerization of hydrophobic and hydrophilic monomers the target globular nanostructures of a "core-shell" morphology appear in a selective solvent. Using a mesoscale computer simulation, we show that the protein-like globules can have a large number of catalytic centers located at the hydrophobic core/hydrophilic shell interface.

  20. Experimental study of flapping jets in a soap film

    Lee, Julia; Kim, Ildoo; Mandre, Shreyas


    Plateau and Rayleigh's observation and explanation on jet instability have inspired us over the years and there has been a significant advance in understanding the jet dynamics. Here, we present a quasi-two-dimensional experimental study of flapping jets in a soap film. Newtonian and non-Newtonian solutions are injected in a flowing soap film. Thinning, break-ups, and beads-on-a-string of the jets, and axisymmetric vortices shredded from the flapping jets are visualized. We employ PIV of the flow motion around the jets to gain an understanding of the roles of instabilities in the flow.

  1. Experimental study of the detonation of technical grade ammonium nitrate

    Presles, Henri-Noël; Vidal, Pierre; Khasainov, Boris


    The detonation of technical grade ammonium nitrate at the density ρ=0.666 g/cm confined in PVC and steel tubes was experimentally studied. The results show that the detonation is self-sustained and steady in steel tubes with diameter as small as 12 mm. Critical detonation diameter lies between 8 and 12 mm in 2 mm thick steel tubes and between 55 and 81 mm in PVC tubes. These values testify a strong detonation sensitivity of this product. To cite this article: H.-N. Presles et al., C. R. Mecanique 337 (2009).

  2. Experimental Study on Vertical Dilute Phase Gas Conveying

    景山; 王金福; 等


    An experimental study of vertical gas conveying Geldart-D powder as a dilute phase is performed in a pipe of length 22m and internal diameter 0.05m using a fluidized blow tank at gas velocity ranging from 5m ·s-1 to 13m·s-1 and loading ratio up to about 30.The characteristics of gas conveying,such as pressure drop,the choking velocity and the minimum primary velocity of the fluidized blow tank,are discussed in detail.

  3. Experimental study on the explosive boiling in saturated liquid nitrogen

    DONG Zhaoyi; HUAI Xiulan; LIU Dengying


    Studies on the heat-transfer characteristics of liquid nitrogen (LN2) have received increasing attention. When there is a transient high heatflux input to the LN2, explosive boiling may take place. In this paper, using the high-power short-duration pulsed laser heating method and the high-speed photography technology, the experimental result of explosive boiling in saturated LN2 is illustrated; and the two exclusive characteristics of explosive boiling in LN2: changeover time and the relative long-time adherence of the bubble cluster to the surface, are investigated.

  4. Experimental Techniques for Studies in Atomic & Molecular Physics

    Heijkenskjöld, Filip


    This thesis is based on a selection of six different experimental techniques used for studies in atomic and molecular physics. The techniques analysed in the thesis are compared to find similarities in strategies and ways to avoid sources of error. Paper 1 deals with collision based spectroscopy with 60 keV Xe6+ ions on sodium and argon gas targets. Information on energy of Rydberg states in Xe5+ is unveiled by optical spectroscopy in the wavelength range from vacuum ultraviolet (VUV) to visi...


    W. Bendaikha


    Full Text Available Hydrogen is a sustainable fuel option and one of the potential solutions for the current energy and environmental problems. In this study hydrogen is produced using a hydrogen generator with a Proton Exchange Membrane (PEM electrolyser. An experimental study is done in the Center of Development of the Renewable Energy, Algiers, Algeria.The experimental device contains essentially a photovoltaic module, a PEM electrolyser, a gasometer and the devices of measures of characteristics of the PEM electrolyser as well as two pyranometers for the horizontal and diffuse global radiance registration. This system in pilots scale is permitted on the one hand, to measured and analyzed the characteristics: of the PEM electrolyser for two different pressures of working (Patm and P=3 bar, on the other hand, to study the volume of hydrogen produces in the time with different sources of electrical power (generator, photovoltaic module, fluorescent lamp, the efficiency for every case is calculated and compared. We present in this paper the variation of the solar hydrogen flow rate produced according to the global radiance and according to the time for a typical day’s of August.

  6. [Endoscopic and histopathological studies of experimental esophageal cancer in beagles].

    Takeshita, K; Sunagawa, M; Nakajima, A; Ochi, K; Habu, H; Hoshi, K


    In order to obtain a reliable experimental model simulating human esophageal cancer, endoscopic and histopathological studies were undertaken in the esophageal cancer produced in the beagle dog. Thirty-seven dogs had been given a solution of N-Ethyl-N'-nitro-N-nitrosoguanidine (ENNG) at a concentration of 150 micrograms/ml for 3-9 months. Follow-up studies included serial endoscopy and biopsy, and almost all animals were eventually sacrificed for histological examination. The results were as follows: Squamous cell carcinoma was observed in 5 out of 22 female dogs, while none in male dogs at all. For the induction of squamous cell carcinoma in the esophagus, administration in the condition of 150 micrograms/ml (75mg/day) for 6-9 months was most suitable. Almost all of esophageal lesions were protruding and well-differentiated squamous cell carcinoma with invasion of the submucosa. The stages of hyperplasia, dysplasia and squamous cell carcinoma in the esophagus were chronologically followed. Carcinoma had been observed in the stomach about 4 months prior to the appearance of esophageal carcinoma. This experimental model was proved to be useful for studies on histogenesis of human esophageal cancer both light and electron microscopically.

  7. Experimental study of friction in aluminium bolted joints

    Croccolo, D.; de Agostinis, M.; Vincenzi, N.


    This study aims at developing an experimental tool useful to define accurately the friction coefficients in bolted joints and, therefore, at relating precisely the tightening torque to the bolt preloading force in some special components used in front motorbike suspensions. The components under investigation are some clamped joints made of aluminium alloy. The preloading force is achieved by applying a torque wrench to the bolt head. Some specific specimens have been appropriately designed and realized in order to study the tribological aspects of the tightening phase. Experimental tests have been performed by applying the Design of Experiment (DOE) method in order to obtain a mathematical model for the friction coefficients. Three replicas of a full factorial DOE at two levels for each variable have been carried out. The levels include cast versus forged aluminium alloy, anodized versus spray-painted surface, lubricated versus unlubricated screw, and first tightening (fresh unspoiled surfaces) versus sixth tightening (spoiled surfaces). The study considers M8x1.25 8.8 galvanized screws.

  8. Experimental and theoretical study on the electrospinning nanoporous fibers process

    Zhao, Jianghui; Si, Na [National Engineering Laboratory for Modern Silk, College of Textile and Clothing Engineering, Soochow University, Suzhou (China); Xu, Lan, E-mail: [National Engineering Laboratory for Modern Silk, College of Textile and Clothing Engineering, Soochow University, Suzhou (China); Nantong Textile Institute of Soochow University, Nantong (China); Tang, Xiaopeng; Song, Yanhua; Sun, Zhaoyang [National Engineering Laboratory for Modern Silk, College of Textile and Clothing Engineering, Soochow University, Suzhou (China)


    Porous materials can be prepared by sol–gel method, hydrothermal synthesis method, electrospinning and other methods. In this paper, electrospun porous nanofibers were prepared by adjusting electrospinning parameters. And the properties of obtained porous nanofiber mats were investigated. Theoretical analysis and experiment research were carried out to research mechanical mechanism of electrospun porous nanofibers, and could be used to optimize and control the porous structure. The theoretical analysis results were further verified according to the experimental data. In addition, Bernoulli equation was used to study the electrospinning “splaying” process. We found the ratio of pore width to pore length was varied along with the variation of the internal pressure of the jet, and the internal pressure of the jet increases with the velocity of the charged jet decreases. - Highlights: • Mechanical mechanism of electrospun porous nanofibers process was studied. • A simplifying gas–liquid two-phase flow model was established. • Bernoulli equation was used to study the electrospinning “splaying” process. • The theoretical results were in good agreement with the experimental data. • The electrospinning parameters affected the surface morphology of charged jet.

  9. Experimental studies of electron-phonon interactions in gallium nitride

    Stanton, N M


    This thesis presents an experimental investigation of the electron-phonon interaction in GaN. Bulk epilayers, grown by MBE, and AIGaN/GaN heterostructure grown by MOCVD, have been studied. The energy relaxation rate for hot electrons has been measured over a wide range of temperatures, allowing both acoustic and optic phonon emission to be studied in GaN epilayers. Direct phonon measurements, both studying the emission and absorption processes, have been performed. Detection of phonons emitted when hot electrons relax their excess energy complements the measurements of relaxation rates. Absorption of acoustic phonons by the epilayers, using both fixed and extended metal film phonon sources, allowed investigation into the effectiveness of the 2k sub F cutoff in the low mobility layers. The experimental findings are compared with the predictions of theory. AIGaN/GaN heterostructures were characterised and measurements of the energy relaxation rate in the temperature range 4K-40K obtained. Excellent agreement wi...


    Yulia Alexandrowna Griber


    Full Text Available The objective of the study was informal social norms of urban culture. The paper contains the detailed description of the experimental situation and the main steps of the field research, focused on the observance of informal social norms in the sphere of urban coloristics. The experiment was conducted in three districts of Smolensk (Russia – Leninskiy, Zadneprovskiy and Promyshlennyy. Particular attention was paid to the analysis of the results of the field research, including evaluation of reaction of participants (residents of multi-storied houses, breakers of informal norms of urban coloristics (experimenters and casual experiment witnesses (neighbors and passersby. In addition, the accuracy of results “forecasting”, done before the beginning of the experiment, is analyzed. The research was conducted using the methodology of breaking experiment that is one of the most provocative ways of studying informal norms in sociology and social psychology. The experiment allowed to draw a number of important conclusions. It showed that urban coloristics is regulated by strict informal norms, that are not noticed by citizens until a violation occurs. The power of informal norms is significantly underestimated by citizens, and their break causes a negative reaction and protest. The most important contribution to the study of informal norms of urban culture was the comparison of the reaction degree by men and women, by the residents of different districts (central, residential or blue-collar neighborhoods, by different age groups.

  11. Radionuclides in fruit systems. A review of experimental studies

    Carini, F.; Spalla, S. [Universita Cattolica del Sacro Cuore, Institute of Agricultural and Environmental Chemistry, Faculty of Agricultural Sciences, Via Emilia Parmense 84, I-29100 Piacenza (Italy); Green, N. [NRPB, Chilton, Didcot, Oxfordshire OX11 0RQ (United Kingdom)


    Existing information on processes and parameters analysed in experimental studies on fruits was reviewed at the inception of the activities of the IAEA BIOMASS Fruits Working Group. Additional information on experimental studies, collected during the activities of the Group and not included in the Review, is presented and discussed in this paper. Studies on deposition of {sup 14}CO{sub 2}, CO{sup 35}S and {sup 3}H{sub 2}O in the gas phase to apple, raspberry, strawberry and blackcurrant have filled gaps in knowledge of uptake of gaseous pollutants in fruit plants, quantifying processes of deposition, translocation and carry-over between seasons. Measurements over a period of six years on vine plants contaminated via leaves and soil by dry deposition of {sup 137}Cs and {sup 90}Sr have improved knowledge of the processes of direct deposition to fruit, translocation and carry-over of radionuclides from year to year. Additional information is given on soil to fruit transfer of U, Th and Pb for apple and mandarin grown under intensive agricultural conditions. (author)

  12. Radionuclides in fruit systems: A review of experimental studies

    Carini, F. [Universita Cattolica del Sacro Cuore, Institute of Agricultural and Environmental Chemistry, Faculty of Agricultural Sciences, Via Emilia Parmense 84, I-29100 Piacenza (Italy)]. E-mail:; Green, N. [NRPB, Chilton, Didcot, Oxfordshire OX11 0RQ (United Kingdom); Spalla, S. [Universita Cattolica del Sacro Cuore, Institute of Agricultural and Environmental Chemistry, Faculty of Agricultural Sciences, Via Emilia Parmense 84, I-29100 Piacenza (Italy)


    Existing information on processes and parameters analysed in experimental studies on fruits was reviewed at the inception of the activities of the IAEA BIOMASS Fruits Working Group. Additional information on experimental studies, collected during the activities of the Group and not included in the Review, is presented and discussed in this paper. Studies on deposition of {sup 14}CO{sub 2}, CO{sup 35}S and {sup 3}H{sub 2}O in the gas phase to apple, raspberry, strawberry and blackcurrant have filled gaps in knowledge of uptake of gaseous pollutants in fruit plants, quantifying processes of deposition, translocation and carry-over between seasons. Measurements over a period of six years on vine plants contaminated via leaves and soil by dry deposition of {sup 137}Cs and {sup 9}Sr have improved knowledge of the processes of direct deposition to fruit, translocation and carry-over of radionuclides from year to year. Additional information is given on soil to fruit transfer of U, Th and Pb for apple and mandarin grown under intensive agricultural conditions.

  13. Experimental Study of Fully Developed Wind Turbine Array Boundary Layer

    Turner v, John; Wosnik, Martin


    Results from an experimental study of an array of up to 100 model wind turbines with 0.25 m diameter, conducted in the turbulent boundary layer of the 6.0 m wide × 2.7 m tall × 72.0 m long test section of the UNH Flow Physics Facility, are reported. The study aims to address two questions. First, for a given configuration (turbine spacing, initial conditions, etc.), when will the model wind farm reach a ``fully developed'' condition, in which turbulence statistics remain the same from one row to the next within and above the wind turbine array. Second, how is kinetic energy transported in the wind turbine array boundary layer (WTABL). Measurements in the fully developed WTABL can provide valuable insight to the optimization of wind farm energy production. Previous experimental studies with smaller model wind farms were unable to reach the fully developed condition. Due to the size of the UNH facility and the current model array, the fully developed WTABL condition can be achieved. The wind turbine array was simulated by a combination of drag-matched porous disks, used in the upstream part of the array, and by a smaller array of realistic, scaled 3-bladed wind turbines immediately upstream of the measurement location.

  14. Experimental and numerical study on fragmentation of steel projectiles

    Hopperstad O.S.


    Full Text Available A previous experimental study on penetration and perforation of circular Weldox 460E target plates with varying thicknesses struck by blunt-nose projectiles revealed that fragmentation of the projectile occurred if the target thickness or impact velocity exceeded a certain value. Thus, numerical simulations that do not account for fragmentation during impact can underestimate the perforation resistance of protective structures. Previous numerical studies have focused primarily on the target plate behaviour. This study considers the behaviour of the projectile and its possible fragmentation during impact. Hardened steel projectiles were launched at varying velocities in a series of Taylor tests. The impact events were captured using a high-speed camera. Fractography of the fragmented projectiles showed that there are several fracture mechanisms present during the fragmentation process. Tensile tests of the projectile material revealed that the hardened material has considerable variations in yield stress and fracture stress and strain. In the finite element model, the stress-strain behaviour from tensile tests was used to model the projectile material with solid elements and the modified Johnson-Cook constitutive relation. Numerical simulations incorporating the variations in material properties are capable of reproducing the experimental fracture patterns, albeit the predicted fragmentation velocities are too low.

  15. Proposal for defining the relevance of drug accumulation derived from single dose study data for modified release dosage forms.

    Scheerans, Christian; Heinig, Roland; Mueck, Wolfgang


    Recently, the European Medicines Agency (EMA) published the new draft guideline on the pharmacokinetic and clinical evaluation of modified release (MR) formulations. The draft guideline contains the new requirement of performing multiple dose (MD) bioequivalence studies, in the case when the MR formulation is expected to show 'relevant' drug accumulation at steady state (SS). This new requirement reveals three fundamental issues, which are discussed in the current work: first, measurement for the extent of drug accumulation (MEDA) predicted from single dose (SD) study data; second, its relationship with the percentage residual area under the plasma concentration-time curve (AUC) outside the dosing interval (τ) after SD administration, %AUC(τ-∞)SD ; and third, the rationale for a threshold of %AUC(τ-∞)SD that predicts 'relevant' drug accumulation at SS. This work revealed that the accumulation ratio RA,AUC , derived from the ratio of the time-averaged plasma concentrations during τ at SS and after SD administration, respectively, is the 'preferred' MEDA for MR formulations. A causal relationship was derived between %AUC(τ-∞)SD and RA,AUC , which is valid for any drug (product) that shows (dose- and time-) linear pharmacokinetics regardless of the shape of the plasma concentration-time curve. Considering AUC thresholds from other guidelines together with the causal relationship between %AUC(τ-∞)SD and RA,AUC indicates that values of %AUC(τ-∞)SD ≤ 20%, resulting in RA,AUC ≤ 1.25, can be considered as leading to non-relevant drug accumulation. Hence, the authors suggest that 20% for %AUC(τ-∞)SD is a reasonable threshold and selection criterion between SD or MD study designs for bioequivalence studies of new MR formulations.

  16. FISH studies of chromosome abnormalities in germ cells and its relevance in reproductive counseling

    Zaida Sarrate; Joan Blanco; Ester Anton; Susana Egozcue; Josep Egozcue; Francesca Vidal


    Chromosome abnormalities are one of the major causes of human infertility. In infertile males, abnormal karyotypes are more frequent than in the general population. Furthermore, meiotic disorders affecting the germ cell-line have been observed in men with normal somatic karyotypes consulting for infertility. In both cases, the production of unbalanced spermatozoa has been demonstrated. Basically addressed to establish reproductive risks, fluorescence in situ hybridization (FISH) on decondensed sperm heads has become the most frequently used method to evaluate the chromosomal constitution of spermatozoa in carriers of numerical sex chromosome abnormalities, carriers of structural chromosome reorganizations and infertile males with normal karyotype. The aim of this review is to present updated figures of the information obtained through sperm FISH studies with an emphasis on its clinical significance. Furthermore, the incorporation of novel FISH-based techniques (Multiplex-FISH; Multi-FISH) in male infertility studies is also discussed.

  17. Introspective Inquiry: Self-Study and Its Relevance in Teacher Education

    Neil Croy


    As teachers inevitably model their teaching on their ownexperiences, those who educate teachers must remainconscious of their own actions in the classroom, lestunwelcome behaviors or ineffective methods resurfacein their students’ future teaching. Therefore, self-studyof one’s professional practice is an invaluable tool forevaluating efficacy in the classroom. This study evaluatedthe teaching practices of Professor Melanie Shoffner(English education) in ENGL 49200, an undergraduatemethods cou...


    Asra Anjum


    Full Text Available Introduction: The word “Placenta” is a Latin word and the Greek equivalent word is “Plakons” which means “Flat cake on a plate”. The placenta is a complex multifunctional organ. It provides nutrition, gas exchange, waste removal, endocrine function and immune support. Placenta is a special circulating system to the developing foetus. Being an organ of vital importance for continuation of pregnancy and foetal nutrition it has evolved great interest among the anatomists, embryologists, pathologists and obstetricians. Materials and Methods: The study was done in 50 placentae which were collected from the department of Obstetrics and Gynaecology in collaboration with the department of Anatomy, Kamineni Institute of Medical Sciences, Narketpally, Nalgonda, Telangana, during the period of 2 years. The morphological variations of placenta, the size, shape, weight and attachment of umbilical cord with its blood vessels were observed, recorded and photographed. The prime objective of the study is to compare and evaluate the morphological alterations of placenta and umbilical cord in pregnancy. Results and Conclusion: In the current study, the majority of the placentae showed round shape, few placentae with oval and irregular and with an accessory lobe in single placenta. The current study also includes variations in insertion of umbilical cords was eccentric in majority, central, marginal and velamentous in a few. Pregnancy induced hypertension significantly affects the placenta by reducing weight and it does not have any significant effect on the shape of placenta, umbilical cord insertion and number of cotyledons on maternal surface. The placenta is the most accurate record of the infants prenatal experience.

  19. The Relevance of Maternal Socioeconomic Characteristics for Low Birth Weight – a Case-Control Study

    Altenhöner, T.; Köhler, M; Philippi, M.


    Introduction: The number of children born underweight (low birth weight, LBW) is increasing despite extensive prevention and screening programmes. The cost is high for the health system, and affected children are burdened with health predictors that can affect them negatively throughout their lives. This study investigates to what extent socioeconomic factors, in addition to known medical causes and the health behaviour of pregnant women, influence LBW. Materials and Methods: In this case-con...

  20. Circulating and Brain BDNF Levels in Stroke Rats. Relevance to Clinical Studies

    Yannick Béjot; Claude Mossiat; Maurice Giroud; Anne Prigent-Tessier; Christine Marie


    BACKGROUND: Whereas brain-derived neurotrophic factor (BDNF) levels are measured in the brain in animal models of stroke, neurotrophin levels in stroke patients are measured in plasma or serum samples. The present study was designed to investigate the meaning of circulating BDNF levels in stroke patients. METHODS AND RESULTS: Unilateral ischemic stroke was induced in rats by the injection of various numbers of microspheres into the carotid circulation in order to mimic the different degrees o...

  1. Astronomical relevance of materials from Earth and space: A laboratory study

    Rauf, Kani Mustafa

    The present study used scanning and transmission electron microscopy, energy dispersive analysis of X-rays (EDAX) and spectroscopy (FTIR, UV-Visible and fluorescence) to examine terrestrial materials of possible astronomical significance (Oedogonium sp., Enteromopha intestinalis, Pelvetia canaliculata, Fucus vesiculosus, Bacillus cereus, Staphyllococcus aureus, poppy seed, chlorophylls 'a' and 'b', Panicum maximum, anthracite, bituminous coal, naphthalene), the Tagish lake and Carancas meteorites, a Kerala red rain sample and stratospheric air particles collected at altitudes of 38-41 km. The study was designed to determine if any of the terrestrial samples could be proposed as an effective model for the interpretation of astronomical spectroscopic observations. The study also set out to search for evidence to shed light on the origin of these meteorites, red rain and stratospheric air particles. The spectra of all the terrestrial samples (including the meteorites) exhibited absorptions in the Mid-IR region, similar to astronomical features displayed by a variety of galactic sources. Algae (Odeogonium sp.) in particular produced the largest number of absorption peaks, most of which matched those of the astronomical emission spectra of PPNe and also the UIBs. Based on these observations, algae could be defended as a biological model for the interpretation of UIBs and PPNe, and a potential candidate for interstellar material. Coal and semi anthracite, that can be regarded as steps in the degradation of biomaterial, preserve the UIB-PPNe spectral features to varying degrees. The results are consistent with the panspermia theory of Hoyle and Wickramasinghe. UV-Visible studies were also conducted on all these materials. The main absorption feature was one close to 217.5 nm (2175 A). The normalized (averaged) spectrum of the whole sequence of biological materials and their degradation products absorption feature at 217.5 nm (2175 A) further support the contention that

  2. Relevance of behavioral and social models to the study of consumer energy decision making and behavior

    Burns, B.A.


    This report reviews social and behavioral science models and techniques for their possible use in understanding and predicting consumer energy decision making and behaviors. A number of models and techniques have been developed that address different aspects of the decision process, use different theoretical bases and approaches, and have been aimed at different audiences. Three major areas of discussion were selected: (1) models of adaptation to social change, (2) decision making and choice, and (3) diffusion of innovation. Within these three areas, the contributions of psychologists, sociologists, economists, marketing researchers, and others were reviewed. Five primary components of the models were identified and compared. The components are: (1) situational characteristics, (2) product characteristics, (3) individual characteristics, (4) social influences, and (5) the interaction or decision rules. The explicit use of behavioral and social science models in energy decision-making and behavior studies has been limited. Examples are given of a small number of energy studies which applied and tested existing models in studying the adoption of energy conservation behaviors and technologies, and solar technology.

  3. Introspective Inquiry: Self-Study and Its Relevance in Teacher Education

    Neil Croy


    Full Text Available As teachers inevitably model their teaching on their ownexperiences, those who educate teachers must remainconscious of their own actions in the classroom, lestunwelcome behaviors or ineffective methods resurfacein their students’ future teaching. Therefore, self-studyof one’s professional practice is an invaluable tool forevaluating efficacy in the classroom. This study evaluatedthe teaching practices of Professor Melanie Shoffner(English education in ENGL 49200, an undergraduatemethods course. The study examined the specificmethods, strategies, and interactions Shoffner uses in herteaching in order to consider how her instruction does—or does not—support the development of her students.Data for the study consisted of my observational notesfrom multiple classes and my review of literature on selfstudyand relational teaching. During each observation, Iused an observational framework of my own design thatrecorded students’ participation and determined the levelof their engagement in classroom discussion, in additionto noting specific interactions between student andinstructor. By analyzing repetitions and common themesfrom my observations, spanning an entire semester, Iconcluded that student engagement in the classroom wasdependent on a variety of classroom activities, such asdiscussion, group work, and lectures. In addition, I foundthat students’ willingness to participate hinged on theprofessor’s use of positive reinforcement, communicatedthrough facial and verbal interaction. These findingssuggest that professors must be conscious of theirchoices in the classroom: seemingly insignificant acts ofinstruction and interaction can greatly influence students’development as future teachers.


    Harsh Kumar


    Full Text Available The coronary sinus is important in many electrophysiological procedures including arrhythmia ablation, biventricular pacing and for deployment of an array of cardiac devices. The advent of advanced invasive and interventional cardiac treatment and management tools for common disorders like heart failure has made understanding of CS anatomy necessary. MATERIAL AND METHODS The study has been conducted in fifty normal hearts available. Length of CS was measured. CS ostium and the Thebesian valve were exposed and measurements taken. Histological study of CS was done. RESULT AND CONCLUSION The presence of myocardial fibres in the wall of CS and their arrangement in the form of circular, longitudinal and tangentially arranged fibres may have regulating function on the flow of blood in the CS. The connection of the muscle fasciculi with the left and the right atrium may have selective role in the conduction and act as an accessory pathway. In the present study the average length of the CS was 30 mm; in the majority (96.0% the CS ostium was oval. In most of the cases (84.0% CS ostium was guarded by thebesian valve, which was semilunar in shape (74%. The valve covered variable area of the ostium.

  5. Experimental study on pollution emission from combustion of blended coals

    Li Yonghua; Chen Hongwei; Zhen Zhi; Liu Jizhen; Feng Zhaoxing; Dong Jianxun [North China Electric Power University, Baoding (China)


    The pollution brought by NOx and SOx produced by coal combustion is getting recognition by each country in the world. This paper adopts an experimental method, selects four kinds of lignite and three kinds of soft coal that are mainly used by some power plant and reports a study of the pollution emission characteristics of component and blended coals. The test rig is introduced from Canada with a capacity of 640 MJ/h with a complete milling system and flue gas online analysis system. The study focuses on the influence of oxygen concentration, pulverized coal fineness and pulverized coal nitrogen content on the pollution emission. The study is useful for achieving clean combustion in large power plants. 5 refs., 4 figs., 7 tabs.

  6. Experimental study and simulation of airflow in solar chimneys

    Saifi, Nadia; Dokkar, Boubekeur; Negrou, Belkhir; Settou, Noureddine [Laboratory for Bioressources Saharan Preservation and Enhancement, University of Kasdi Merbah (Algeria)], e-mail:


    With the depletion of traditional energies, new technologies are arising that use renewable energies. The aim of this paper is to present a study of airflow in solar chimneys. Mathematical simulation and experiments were carried out on solar chimneys with different geometries. It was found that the width of the channel and the angle of inclination of the chimney influence the field speed. A case study was then carried out on a solar chimney in Ouargla Province, Algeria, to assess the impact of a chimney's inclination on its performance. The simulation was conducted using a finite volume method in Fluent 6.3.26 computer software. A good match between experimental and simulation results was found. This paper presented a study on airflow in solar chimney and demonstrated that simulations using Fluent and the finite element method were able to provide good results.

  7. Long term studies of depression: what is relevant for the physician?

    Eric Fakra


    Full Text Available Following a meticulous review of long term studies of depression, we conclude that prolonging antidepressant medication after full recovery is clearly beneficial. In this article, we examine recent long term studies that reveal substantial evidence in this sense. However, we advise physicians to keep in mind that this prophylactic effect has been proven for a restricted population, i.e., patients showing recurrent depressive disorders with low comorbidity on axis 1, and having revealed a satisfying response to antidepressant agents during the acute phase of the index episode. This does not mean that antidepressant agents are not useful for patients showing other characteristics, but more studies are needed to assert this possible advantage. We also examine the limited data on chronic forms of depressive disorders. The effect of long term prescription is believed to be advantageous as long as the medication is taken; it has been demonstrated for up to 5 years. Full dosage is indicated even if the effect of active drug over placebo persists at lower doses. The differences between antidepressant agents appear minor and physicians should be more concerned about the long term tolerance of these drugs than their efficacy when choosing the appropriate medication for maintenance treatment. Physicians should also be aware of the greater risk of recurrence during the 6 months following the discontinuation of medication. This risk occurs regardless of the total length of prescription. The possibility that recurrence may be mistaken for withdrawal symptoms cannot be ruled out. Finally, the side-effects of antidepressant drugs are a major concern, particularly when extending the length of prescription. Even though the newer generation medications display a more favorable short-term side-effect profile, the effects of chronic use of these agents are still unclear. Therefore, the decision to extend treatment over several years requires comprehensive discussion

  8. Perceptions of the relevance of mathematics and science: An Australian study

    Jones, Jennifer; Young, Deidra J.


    This study examined students from schools mostly in Sydney and Wollongong (New South Wales, Australia). While the private girls' school used in this survey has had a very good record of girls staying on in physics, some of the public schools surveyed have had very low retention rates (and not only in the science and mathematics areas). This paper attempts to describe student differences in perceptions and attitudes and how these are related to gender and type of school. Additionally, students' perceived reasons for not performing well in mathematics and science were investigated.




    Full Text Available Family life education is a comprehensive program to educate the growing children, regarding the various aspects of living in a society and interacting with other individuals at different levels and in different ways along with imparting age appropriate knowledge of biological and sexual development. Lack of awareness, ignorance, or inappropriate knowledge among youth made us take up this study. Sexual knowledge is sought from peers and magazines, menstrual hygiene, masturbation issues are never dealt by health authorities, educators or parents. Risk taking behavior, substance abuse, violence are very common in teens these problems are to highlighted. And interactive sessions are needed to enhance the learning experience.


    Luiz Claudio Gonçalves


    Full Text Available The process of public participation in decision-making in a national social environmental, is not properly systematized, has some shortcomings and misconceptions needing so adjustments allowing for its correct operation and application.This article, through a literature review discusses the major foundations and approaches to support effective public participation in social environmental assessment processes. Methodologically, this study was also based on a case performed in Hydroelectric Tucuruí, which made use of semi-structured interviews with technicians and staff work, aimed at collecting information about the effective participation of civil society in decision-making in various stages of this project

  11. Facial Nerve in Foetal Cadavers: An Anatomical Study with Clinical Relevance

    Kotian SR


    Full Text Available Introduction: Facial nerve paralysis is a major complication of parotid surgery and is widely reported. Little attention is paid to the facial nerve trunk in children. The facial nerve trunk in children and infants can be easily injured since they lie close to the surface. The present study therefore intends to describe the variability in the facial nerve trunk and its branching pattern in foetuses. Methods: The study was done bilaterally in 30 formalin-fixed foetuses (15 females, 15 males, age ranging from 21.0 to 35.5 weeks of gestation. The length of the facial nerve trunk was measured and bifurcation and trifurcation of the trunk was examined. Variability in the branching pattern was also noted. Results: The most common facial nerve trunk branching type was bifurcation (53.33%, followed by trifurcation (33.33%. Multiple branching of the facial nerve was also observed in 13.34% of the cases. Other variations related to the facial nerve were also noted. The mean length of the facial nerve trunk was 7.15 ± 2.12 mm. There was no significant difference between the right and left sides and in case of males and female foetuses. Conclusion: Facial nerve injury during parotid surgery is a main cause of paediatric facial paralysis. The length of the facial nerve trunk therefore must be accurately known in any surgical procedure planned in the area. The main furcation of the facial nerve should also receive special attention.

  12. Photoreaction of thioxanthone with indolic and phenolic derivatives of biological relevance: magnetic field effect study.

    Das, Doyel; Nath, Deb Narayan


    The photoinduced reaction of thioxanthone (TX) with various indolic and phenolic derivatives and amino acids like tryptophan and tyrosine has been monitored in sodium dodecyl sulfate micellar medium. Laser flash photolysis and magnetic field effect (MFE) experiments have been used to study the dynamics of the radical pairs. The quenching rate constant with different quenchers in SDS micellar solution has been measured. For indoles the electron-transfer reaction has been found to be followed by proton transfer from the donor molecule, which gives rise to the TX ketyl radical. On the other hand, the electron-transfer reaction in the case of phenols is preceded with formation of a hydrogen-bonded exciplex. The extent of the MFE and magnitude of the magnetic field corresponding to one-half of the saturation value of MFE ( B 1/2) support the fact that hyperfine mechanism plays the primary role. Quenching of MFE in the presence of gadolinium ions confirms that the radical pair is located near the micellar interface. MFE study has been further extended to protein-like bovine serum albumin in micellar solution. The results indicate loss in mobililty of radical pairs in the protein surfactant complex.


    Kali Vara Prasad


    Full Text Available BACK GROUND : Synovial biopsy is considered as the gold standard in the diagnosis of various joint disorders and synovial diseases. But sometimes the definitive diagnosis is elusive only by doing biopsy then clinical, hematological and x - ray examinations will help. The advantage with arthroscopic synovial biopsy is that it is easy to perform, minimal discomfort to the patient and can be done at intervals if the diagnosis can n ot be made in the first examination. MATERIAL & METHODS : The present study was conducted in the Department of Orthopedics & Traumatology, Osmania General Hospital/ Medical College, Hyderabad. The duration of the study was from Sept 2012 to Sept 2014. CONCLUSIONS : Arthroscopic synovial biopsy is the mainstay in the management of Joint disorders and Synovial diseases. It is patient friendly and repeated procedures can be undertaken when the definitive diagnosis could not be established in the initial attempt, as is common in some cases of Non - specific synovitis, later being diagnosed either as Osteoarthritis or Rheumatoid Arthritis. This is the greatest advantage in using this procedure.

  14. [Relevance of preoperative anxiety for postoperative outcome in urological surgery patients: A prospective observational study].

    Laufenberg-Feldmann, R; Kappis, B; Schuster, M; Ferner, M


    Preoperative anxiety is not systematically assessed during premedication appointments, although it may influence the postoperative course and outcome. The aim of this study was to assess preoperative anxiety in a sample of patients before major urological surgery and to characterize the impact on postoperative pain. An additional aim was to analyze the agreement between patients' self-ratings and physicians' anxiety ratings. In all, 127 male and 27 female patients participated in a prospective observational study. Preoperative anxiety was assessed with two validated instruments - the APAIS (Amsterdam Preoperative Anxiety and Information Scale) and the State Scale of the STOA questionnaire (State-Trait Operation Anxiety) - during the premedication appointment. Physicians provided their subjective ratings on patients' anxiety and need for information using the APAIS. The predictive value of preoperative anxiety for postoperative pain was evaluated. Nearly four out of ten patients were identified as "anxiety cases"; thereof women were more afraid than men were. Preoperative anxiety was not correctly assessed by physicians, who overestimated patients' anxiety. In female patients, preoperative anxiety was predictive of increased postoperative pain scores. Preoperative anxiety is a frequent concern and often not correctly assessed by physicians. The use of scoring systems to detect preoperative anxiety is useful in clinical routine and helps to decide on therapeutic interventions.

  15. Experimental and quantum chemical studies on poriferasterol - A natural phytosterol isolated from Cassia sophera Linn. (Caesalpiniaceae)

    Brahmachari, Goutam; Mondal, Avijit; Nayek, Nayana; Kumar, Abhishek; Srivastava, Ambrish Kumar; Misra, Neeraj


    Poriferasterol, a biologically relevant phytosterol, has been isolated and identified first-time from Cassia sophera Linn. (family: Caesalpiniaceae) based on detailed spectral studies. Exhaustive theoretical studies on the molecular structure, vibrational spectra, HOMO, LUMO, MESP surfaces and reactivity descriptor of this plant-derived natural molecule have been performed. The experimentally observed FT-IR spectrum of the title compound has been compared with spectral data obtained by DFT-B3LYP/6-311 + G (d,p) method. The UV-visible spectrum of the title compound has also been recorded and the electronic properties, such as frontier orbitals and band gap energy are measured by TD-DFT approach. The 1H and 13C NMR spectrum has been calculated by using the gauge independent atomic orbital method and compared with the observed data.

  16. Fundamental Studies of Charge Migration and Delocalization Relevant to Solar Energy Conversion

    Michael J. Therien


    This program aimed to understand the molecular-level principles by which complex chemical systems carry out photochemical charge separation, transport, and storage, and how these insights could impact the design of practical solar energy conversion and storage devices. Towards these goals, this program focused on: (1) carrying out fundamental mechanistic and transient dynamical studies of proton-coupled electron-transfer (PCET) reactions; (2) characterizing and interrogating via electron paramagnetic resonance (EPR) spectroscopic methods novel conjugated materials that feature large charge delocalization lengths; and (3) exploring excitation delocalization and migration, as well as polaron transport properties of meso-scale assemblies that are capable of segregating light-harvesting antennae, nanoscale wire-like conduction elements, and distinct oxidizing and reducing environments.

  17. The Relevance of Maternal Socioeconomic Characteristics for Low Birth Weight – a Case-Control Study

    Altenhöner, T.; Köhler, M.; Philippi, M.


    Introduction: The number of children born underweight (low birth weight, LBW) is increasing despite extensive prevention and screening programmes. The cost is high for the health system, and affected children are burdened with health predictors that can affect them negatively throughout their lives. This study investigates to what extent socioeconomic factors, in addition to known medical causes and the health behaviour of pregnant women, influence LBW. Materials and Methods: In this case-control study 131 mothers of singletons with a birth weight ≤ 2500 g (cases) and 323 mothers of normal birth weight babies (controls) were interviewed with respect to socioeconomic status, health behaviour and stress in the workplace. Medical data were collected by specialist staff using a questionnaire. Results: Independent of medical diagnosis and health behaviour, women with lower level education (OR [95 % CI] = 2.24 [1.12; 4.51]) and those who were not working (OR [95 % CI] = 1.82 [1.10; 3.00]) were more likely to have an LBW baby. No effect was shown for immigrant background (OR [95 % CI] = 1.14 [0.59; 2.21]) or stress in the workplace (OR [95 % CI] = 1.17 [0.90; 1.51]). Discussion and Conclusion: These results show that the association between social and health inequalities starts from before birth. In order to reduce the rising number of babies born underweight, socioeconomic determinants in the care and supervision of pregnant women should systematically receive more attention to enable appropriate early preventive strategies to be implemented. PMID:27065486

  18. Experimental Study on Abrasive Water Jet Machining of PZT Ceramic

    Dhanawade, Ajit; Upadhyai, Ravi; Rouniyar, Arunkumar; Kumar, Shailendra


    This paper presents research work involved in abrasive water jet machining of PZT ceramic material. Process parameters namely stand-off distance, water pressure and traverse rate are considered in the present study. Response surface methodology approach is used to design the experiments. Relative significance of process parameters and their influence on kerf properties are identified on the basis of analysis of variance. It is found that water pressure and traverse rate are most significant parameters followed by stand-off distance. On the basis of experimental analysis, regression models are developed to predict kerf taper and depth of cut. The models are developed with respect to significant parameters, interaction and quadratic terms. It is found that model predictions are in congruence with experimental results. Multi-response optimization of process parameters is also performed using desirability approach in order to minimize kerf taper and maximize depth of cut. Kerf wall features of machined surfaces are observed using scanning electron microscope. The findings of present study are useful to improve kerf properties in abrasive water jet machining of PZT ceramic materials.

  19. Experimental study of entrainment phenomenon in a trapped vortex combustor

    Zhang Rongchun; Fan Weijun


    Trapped vortex combustor (TVC) is an advanced low-pollution gas turbine combustor,with the adoption of staged combustion technique.To achieve low-pollutant emission and better combustion performance,the proportion of the air flow in each combustion zone should be precisely determined in the design of the combustor.Due to the presence of entrainment phenomenon,the total air flow in the cavity zone is difficult to estimate.To overcome the measurement difficulty,this study adopts the indirect measurement approach in the experimental research of entrainment phenomenon in the cavity.In accordance with the measurement principle,a TVC model fueled by methane is designed.Under two experimental conditions,i.e.with and without direct air intake in the cavity,the influence of the mainstream air flow velocity,the air intake velocity in the cavity,the height of inlet channel,the structure of holder and the structural proportion of the cavity on entrainment in the cavity is studied,respectively,through experiment at atmospheric temperature and pressure.The results suggest that the air flow velocity of mainstream,the air intake velocity of the cavity and the structure of the holder exert significant influence on the air entrainment,while the influence of structural proportion of the cavity is comparatively insignificant.The square root of momentum ratio of cavity air to mainstream air could be used to analyze the correlation of the entrainment data.

  20. Biofouling in forward osmosis systems: An experimental and numerical study

    Bucs, Szilard


    This study evaluates with numerical simulations supported by experimental data the impact of biofouling on membrane performance in a cross-flow forward osmosis (FO) system. The two-dimensional numerical model couples liquid flow with solute transport in the FO feed and draw channels, in the FO membrane support layer and in the biofilm developed on one or both sides of the membrane. The developed model was tested against experimental measurements at various osmotic pressure differences and in batch operation without and with the presence of biofilm on the membrane active layer. Numerical studies explored the effect of biofilm properties (thickness, hydraulic permeability and porosity), biofilm membrane surface coverage, and biofilm location on salt external concentration polarization and on the permeation flux. The numerical simulations revealed that (i) when biofouling occurs, external concentration polarization became important, (ii) the biofilm hydraulic permeability and membrane surface coverage have the highest impact on water flux, and (iii) the biofilm formed in the draw channel impacts the process performance more than when formed in the feed channel. The proposed mathematical model helps to understand the impact of biofouling in FO membrane systems and to develop possible strategies to reduce and control biofouling. © 2016 Elsevier Ltd