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Sample records for preliminary study transient

  1. A Preliminary Study on Bucket Foundations under Transient Lateral Loading

    DEFF Research Database (Denmark)

    Foglia, Aligi; Ibsen, Lars Bo; Nielsen, Søren Kjær;

    2013-01-01

    This study aims at investigating the behaviour of monopod bucket foundations through a physical model. The foundation is installed in dense water-saturated sand and is subjected to lateral load applied at different rates. The different loading rates allow for exploring the patterns of response of...

  2. A Preliminary Study on Bucket Foundations under Transient Lateral Loading

    DEFF Research Database (Denmark)

    Foglia, Aligi; Ibsen, Lars Bo; Nielsen, Søren Kjær;

    2013-01-01

    This study aims at investigating the behaviour of monopod bucket foundations through a physical model. The foundation is installed in dense water-saturated sand and is subjected to lateral load applied at different rates. The different loading rates allow for exploring the patterns of response...... of bucket foundations in different drainage conditions. Particular focus is given to the rapid loading response of the foundation (simulating a 50 year wave or emergency stop of a wind turbine). Important knowledge on the pore pressure development within and around the foundation during loading is achieved....

  3. PHOEBUS/UHTREX: a preliminary study of a low-cost facility for transient tests of LMFBR fuel

    Energy Technology Data Exchange (ETDEWEB)

    Kirk, W.L. (comp.)

    1976-08-01

    The results of a brief preliminary design study of a facility for transient nuclear tests of fast breeder reactor fuel are described. The study is based on the use of a reactor building originally built for the UHTREX reactor, and the use of some reactor hardware and reactor design and fabrication technology remaining from the Phoebus-2 reactor of the Rover nulcear rocket propulsion program. The facility is therefore currently identified as the PHOEBUS/UHTREX facility. This facility is believed capable of providing early information regarding fast reactor core accident energetics issues which will be very valuable to the overall LMFBR safety program. Facility performance in conjunction with a reference 127-fuel pin experiment is described. Low cost and early availability of the facility were emphasized in the selection of design features and parameters.

  4. Preliminary EEG study of protective effects of Tebonin in transient global cerebral ischemia in rats

    DEFF Research Database (Denmark)

    Zagrean, L; Vatasescu, R; Munteanu, A M

    2000-01-01

    and metabolism. The objective of this study was to investigate the effects of preventive treatment with Ginkgo biloba extract (EGb 761--Tebonin) in cerebral global ischemia and reperfusion in rats using computerized EEG analysis. Ginkgo biloba extract, known to be, in vitro, a free radicals scavanger and a PAF.......0015). Computerized spectral analysis of EEG has shown that the percentage of slow waves at 10 minutes after reperfusion was 117% higher in control group than in Ginkgo biloba group (p

  5. Preliminary Study on Mass Flow Rate in Passive Cooling Experimental Simulation During Transient Using NC-Queen Apparatus

    Directory of Open Access Journals (Sweden)

    M. Juarsa

    2014-12-01

    Full Text Available The research related to thermal management has been significantly inreased, especially for NPP safety. The use of passive cooling systems both during the accident and operation become reliable in the advanced reactor safety systems. Therefore it should be enhanced through experimental studies to investigate heat transfer phenomenon of the heat decay in transient cooling condition.An investigation has been performed through experiment using an NC-Queen apparatusconstructed with rectangular loop. Piping were consisting of tubes of SS316L with diameter, length, and width of 3/4 inch, 2.7 m, and 0.5 m respectively. The height between heater and cooler was 1.4 m. The experiment used initial water temperature at 70oC, 80oC, and 90oC in heater area. Transient temperature was used as experimental data to calculate water mass flow rate. The results showed that the temperature in heater area and cooler area were decreasing of about 90.6% and 95.7% at initial temperatur of 80oC, and of about 71.1% and 59.4% at initial temperature of 70oC. Those results were at higher initial temperature of 90oC compared with the initial temperature of 90oC. The average of water mass flow rate increased 81.03% from initial temperatur of 70oC. It was shown that the averages of removed heat in every second from water due to heat loss and cooler,were 3.51 watts, 5.06 watts and 6.85 watts respectively. The initial condition of heat stored in the water was quite different, but to the cooler heat removal capacity and heat loss was almost the same.

  6. Preliminary Analysis of the Transient Reactor Test Facility (TREAT) with PROTEUS

    Energy Technology Data Exchange (ETDEWEB)

    Connaway, H. M. [Argonne National Lab. (ANL), Argonne, IL (United States); Lee, C. H. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2015-11-30

    The neutron transport code PROTEUS has been used to perform preliminary simulations of the Transient Reactor Test Facility (TREAT). TREAT is an experimental reactor designed for the testing of nuclear fuels and other materials under transient conditions. It operated from 1959 to 1994, when it was placed on non-operational standby. The restart of TREAT to support the U.S. Department of Energy’s resumption of transient testing is currently underway. Both single assembly and assembly-homogenized full core models have been evaluated. Simulations were performed using a historic set of WIMS-ANL-generated cross-sections as well as a new set of Serpent-generated cross-sections. To support this work, further analyses were also performed using additional codes in order to investigate particular aspects of TREAT modeling. DIF3D and the Monte-Carlo codes MCNP and Serpent were utilized in these studies. MCNP and Serpent were used to evaluate the effect of geometry homogenization on the simulation results and to support code-to-code comparisons. New meshes for the PROTEUS simulations were created using the CUBIT toolkit, with additional meshes generated via conversion of selected DIF3D models to support code-to-code verifications. All current analyses have focused on code-to-code verifications, with additional verification and validation studies planned. The analysis of TREAT with PROTEUS-SN is an ongoing project. This report documents the studies that have been performed thus far, and highlights key challenges to address in future work.

  7. Preliminary report on the CTS transient event counter performance through the 1976 spring eclipse season

    Science.gov (United States)

    Stevens, N. J.; Lovell, R. R.; Klinect, V. W.

    1977-01-01

    The transient event counter is described, defining its operational characteristics, and presenting the preliminary results obtained through the first 90 days of operation including the Spring 1976 eclipse season. The results show that the CTS was charged to the point where discharges have occurred. The discharge induced transients have not caused any anomalous events in spacecraft operation. The data indicate that discharges can occur at any time during the day without preference to any local time quadrant. The number of discharges occurring in the 1 sec sample interval are greater than anticipated.

  8. Muhammadiyah: A Preliminary Study

    Directory of Open Access Journals (Sweden)

    Azyumardi Azra

    2014-03-01

    Full Text Available This article is a collection of Bibliography reviewer that discuss Muhammadiyah. The following are some of the bibliography were reviewed:A.R. Sukrianta dan Abdul Munir Malkhan, Perkembangan Pemikiran Muhammadiyah dari Masa ke Masa: Menyambut Muktamar ke-41, (Yogyakarta: Dua Dimensi, 1985.A.R. Sukriyanto dan Abdul Munir Mulkhan, Pergumulan Pemikiran dalam Muhammadiyah, (Yogyakarta: Sipress, 1990.Ruslan Abdul Gani. et.al., Cita dan Citra Muhammadiyah, (Jakarta: Pustaka Panjimas, 1985.M.T. Arifin, Gagasan Pembaharuan Muhammadiyah, (Jakarta: Pustaka Jaya, 1987.M.T. Arifin, Muhammadiyah: Potret yang Berubah, (Surakarta: Institut Gelanggang Pemikiran Filsafat Sosial Budaya dan Kependidikan, 1990.M. Yusron Asrofie, Kiyai Haji Ahmad Dahlan, Pemikiran dan Kepemimpinannya, (Yogyakarta: Yogyakarta Offset, 1983.Fathurrahman Djamil, Ijtihad Muhammadiyah dalam Masalah-masalah Fiqh Kontemporer, (Jakarta: Doctoral Dissertation the State Institute of Islamic Studies (IAIN, 1994.Yunahar Ilyas. et.al., Muhammadiyah dan NU: Reorientasi Wawasan Keislaman, (Yogyakarta: LPPI UMY, LKPSM NU, & PP al-Muhsin, 1993.Musthafa kamal, Chusnan Yusuf, dan Rosyad Sholeh, Muhammadiyah sebagai Gerakan Islam, (Yogyakarta: Penerbit Persatuan, 1976.M. Rusli Karim, Muhammadiyah dalam Kritik dan Komentar, (Jakarta: Rajawali, 1986.Arbiyah Lubis, Pemikiran Muhammadiyah dan Muhammad Abduh: Suatu Studi Perbandingan, (Jakarta: Doctoral Dissertation the State Institute of Islamic Studies (IAIN, 1989.Abdul Munir Mulkhan, Pemikiran K.H. Ahmad Dahlan dan Muhammadiyah dalam Perspektif Perubahan Sosial, (Jakarta: Bumi Aksara, 1990.Abdul Munir Mulkhan, Pak AR Menjawab 245 Permasalahan dalam Islam, (Yogyakarta: Sipress, 1990.M. Din Syamsuddin, Muhammadiyah Kini dan Esok, (Jakarta: Pustaka Panjimas, 1990.H.S. Prodjokusumo, Melestarikan Muhammadiyah, (Jakarta: Pimpinan Pusat Muhammadiyah, 1985.Yusuf Abdullah Puar, Perjuangan dan Pengabdian Muhammadiyah, (Jakarta: Pustaka Antara, 1989.Sahlan Rosidi

  9. A transient absorption study of allophycocyanin

    Indian Academy of Sciences (India)

    Y J Shiu; J M Zhang; M Hayashi; V Gulbinas; C M Yang; S H Lin

    2002-12-01

    Transient dynamics of allophycocyanin trimers and monomers are observed by using the pump-probe, transient absorption technique. The origin of spectral components of the transient absorption spectra is discussed in terms of both kinetics and spectroscopy. We find that the energy gap between the ground and excited states of the unexcited subunit of allophycocyanin monomer decreases via an interaction with another excited subunit. For allophycocyanin trimer, we find that the fast dynamics results from the fast internal conversion and the first excited state is the only one electronic state which can trap the final population.

  10. Transient fault behavior in a microprocessor: A case study

    Science.gov (United States)

    Duba, Patrick

    1989-01-01

    An experimental analysis is described which studies the susceptibility of a microprocessor based jet engine controller to upsets caused by current and voltage transients. A design automation environment which allows the run time injection of transients and the tracing from their impact device to the pin level is described. The resulting error data are categorized by the charge levels of the injected transients by location and by their potential to cause logic upsets, latched errors, and pin errors. The results show a 3 picoCouloumb threshold, below which the transients have little impact. An Arithmetic and Logic Unit transient is most likely to result in logic upsets and pin errors (i.e., impact the external environment). The transients in the countdown unit are potentially serious since they can result in latched errors, thus causing latent faults. Suggestions to protect the processor against these errors, by incorporating internal error detection and transient suppression techniques, are also made.

  11. Multiwavelength Studies of Rotating Radio Transients

    CERN Document Server

    Miller, Joshua; Rea, Nanda; Keane, Evan; Lyne, Andrew; Kramer, Michael; Manchester, Richard; Lazaridis, Kosmas

    2011-01-01

    We describe our studies of the radio and high-energy properties of Rotating Radio Transients (RRATs). We find that the radio pulse intensity distributions are log-normal, with power-law tails evident in two cases. For the three RRATs with coverage over a wide range of frequency, the mean spectral index is -1.7\\pm0.1, roughly in the range of normal pulsars. We do not observe anomalous magnetar-like spectra for any RRATs. Our 94-ks XMM-Newton observation of the high magnetic field RRAT J1819-1458 reveals a blackbody spectrum (kT ~130 eV) with an unusual absorption feature at ~1 keV. We find no evidence for X-ray bursts or other X-ray variability. We performed a correlation analysis of the X-ray photons with radio pulses detected in concurrent observations with the Green Bank, Effelsberg, and Parkes telescopes. We find no evidence for any correlations between radio pulse emission and X-ray photons, perhaps suggesting that sporadicity is not due to variations in magnetospheric particle density but to changes in b...

  12. Numerical study of transient nonlinear harbor resonance

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    It is generally accepted that nonlinear wave-wave interactions play an important role in harbor resonance. Nevertheless it is not clear how waves take part in those interactions. The aim of this paper is to investigate those processes for a rectangular harbor at transient phases. Long-period oscillations excited by bichromatic waves are simulated by the Boussinesq model. The simulations start from calm conditions for the purpose of studying the response process. The internal wavemaker stops working after the oscillations have reached a quasi-steady state, and it is used to simulate the damp process. In order to analyze temporary features of wave-wave interactions in different states, the wavelet-based bispectrum is employed. The influence of the short wave frequencies on long-period oscillations is investigated, and reasons are tried to be given from nonlinear triad interactions between different wave components and the interaction of short waves and the bay entrance. Finally, the response time and the damp time are estimated by a simple method.

  13. Transient Studies of a Sodium Sulfur Cell

    Science.gov (United States)

    Caprio, Sarah

    Modern grids will include input from fossil-fueled power generation facilities as well as renewable energy sources, and these are expected to work together actively. One major problem with this integrated power production is that most renewable energy sources are intermittent and variable, and thus introduce a very challenging situation with regard to grid stability and reliability. Also, fossil-fueled power generation facilities have load cycles based on expected usage. A non-reliable power source cannot feasibly be used to supply the grid with proper amounts of energy needed in peak times. A solution to this dilemma is power storage. The sodium-sulfur battery has high potential for electrical storage at the grid level due to its high energy density, low cost of the reactants, and high open-circuit voltage. However, the use of sodium-sulfur batteries at the grid level requires high current density operation that can cause cell deterioration, leading to lower sulfur utilization and lower energy efficiency. In addition, it can result in undesired thermal runaway leading to potentially hazardous situations. A rigorous, dynamic model of a sodium-sulfur battery can be used to study these phenomena, design the battery for optimal transient performance, and develop mitigation strategies. Most literature on sodium-sulfur batteries is concerned the dynamics of the sulfur electrode (a sodium-polysulfide melt). There is limited data in the open literature for dynamics of an entire cell. With this motivation, a first-principles dynamic model of a sodium-sulfur cell (with beta"-alumina electrolyte) has been developed. The state of discharge (SOD) of a sodium-sulfur cell significantly affects the heat generation rate, rates of electrochemical reactions, and internal resistance. To capture these phenomena correctly, a fully coupled thermal-electrochemical model has been developed. The thermal model considers heat generation due to Ohmic loss, Peltier heat, and heat due to the

  14. Alaska gold rush trails study: Preliminary draft

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Preliminary study draft, with maps, of seven gold rush trails in Alaska, to determine suitability for inclusion in the National Scenic Trails system and their...

  15. Metabolic studies of transient tyrosinemia in premature infants

    Science.gov (United States)

    Fernbach, S. A.; Summons, R. E.; Pereira, W. E.; Duffield, A. M.

    1975-01-01

    The recently developed technique of gas chromatography-mass spectrometry supported by computer has considerably improved the analysis of physiologic fluids. This study attempted to demonstrate the value of this system in the investigation of metabolite patterns in urine in two metabolic problems of prematurity, transient tyrosinemia and late metabolic acidosis. Serial 24-hr urine specimens were analyzed in 9 infants. Transient tyrosinemia, characterized by 5- 10-fold increases over basal excretion of tyrosine, p-hydroxyphenyllactate, and p-hydroxyphenylpyruvate in urine, was noted in five of the infants. Late metabolic acidosis was seen in four infants, but bore no relation to transient tyrosinemia.

  16. Optical studies of shock generated transient supersonic base flows

    Science.gov (United States)

    Liang, P.-Y.; Bershader, D.; Wray, A.

    1982-01-01

    A shock tube employing interferometric and schlieren techniques is used to study transient base flow phenomena following shock wave passage over two plane bluff bodies: a hemicircular cylinder and a cylinder with the Galileo Jovian probe profile. An attempt is made to understand the physics of transition from transient to steady state flow, and to provide code verification for a study employing the Illiac IV computer. Transient base flow interactions include a series of shock diffraction, regular, and Mach reflections, coupled with boundary layer development, separation, and recompression. Vorticity generation and transport underlie these features. The quantitative verification of the computer code includes comparisons of transient pressure and density fields, near wake geometries, and bow shock standoff distances.

  17. Coupling capacitor voltage transformer: A model for electromagnetic transient studies

    Energy Technology Data Exchange (ETDEWEB)

    Fernandes, D.; Neves, W.L.A. [Department of Electrical Engineering, Federal University of Campina Grande, Av. Aprigio Veloso, 882 Bodocongo, 58.109-970 Campina Grande, PB (Brazil); Vasconcelos, J.C.A. [Companhia Hidro Eletrica do Sao Francisco, Rua Delmiro Gouveia, 333 Bongi, 50.761-901 Recife, PE (Brazil)

    2007-02-15

    In this work, an accurate coupling capacitor voltage transformer (CCVT) model for electromagnetic transient studies is presented. The model takes into account linear and nonlinear elements. A support routine was developed to compute the linear 230kV CCVT parameters (resistances, inductances and capacitances) from frequency response data. The magnetic core and surge arrester nonlinear characteristics were estimated from laboratory measurements as well. The model is used in connection with the electromagnetic transients program (EMTP) to predict the CCVT performance when it is submitted to transient overvoltages, as are the cases of voltages due to the ferroresonance phenomenon and circuit breaker switching. The difference between simulated and measured results is fairly small. Simulations had shown that transient overvoltages produced inside the CCVT, when a short circuit is cleared at the CCVT secondary side, are effectively damped out by the ferroresonance suppression circuit and the protection circuit. (author)

  18. Ultraviolet transient absorption, transient grating and photon echo studies of aqueous tryptophan

    Science.gov (United States)

    Ajdarzadeh, Ahmad; Consani, Cristina; Bräm, Olivier; Tortschanoff, Andreas; Cannizzo, Andrea; Chergui, Majed

    2013-08-01

    We compare UV transient grating (TG) experiments of aqueous tryptophan with transient absorption (TA) and fluorescence up-conversion measurements. The TG and TA signals show a bi-exponential rise with sub-ps and ps time constants, which are consistent with the fluorescence studies. Using experimental data, we provide an equation for the homodyne-detected TG signal, taking into account the sub-100 fs internal conversion of tryptophan after excitation. In addition, we measure a sub-100 fs homogeneous electronic dephasing time for tryptophan in water by the photon echo (PE) technique. These measurements provide a consistent picture of excited state dynamics of aqueous tryptophan that may serve as a basis for coherent 2D-UV spectroscopy of biosystems.

  19. Multiwavelength Studies of Rotating Radio Transients

    Science.gov (United States)

    Miller, Joshua J.

    Seven years ago, a new class of pulsars called the Rotating Radio Transients (RRATs) was discovered with the Parkes radio telescope in Australia (McLaughlin et al., 2006). These neutron stars are characterized by strong radio bursts at repeatable dispersion measures, but not detectable using standard periodicity-search algorithms. We now know of roughly 100 of these objects, discovered in new surveys and re-analysis of archival survey data. They generally have longer periods than those of the normal pulsar population, and several have high magnetic fields, similar to those other neutron star populations like the X-ray bright magnetars. However, some of the RRATs have spin-down properties very similar to those of normal pulsars, making it difficult to determine the cause of their unusual emission and possible evolutionary relationships between them and other classes of neutron stars. We have calculated single-pulse flux densities for eight RRAT sources observed using the Parkes radio telescope. Like normal pulsars, the pulse amplitude distributions are well described by log-normal probability distribution functions, though two show evidence for an additional power-law tail. Spectral indices are calculated for the seven RRATs which were detected at multiple frequencies. These RRATs have a mean spectral index of = -3.2(7), or = -3.1(1) when using mean flux densities derived from fitting log-normal probability distribution functions to the pulse amplitude distributions, suggesting that the RRATs have steeper spectra than normal pulsars. When only considering the three RRATs for which we have a wide range of observing frequencies, however, and become --1.7(1) and --2.0(1), respectively, and are roughly consistent with those measured for normal pulsars. In all cases, these spectral indices exclude magnetar-like flat spectra. For PSR J1819--1458, the RRAT with the highest bursting rate, pulses were detected at 685 and 3029 MHz in simultaneous observations and have a

  20. [Study on transient absorption spectrum of tungsten nanoparticle with HepG2 tumor cell].

    Science.gov (United States)

    Cao, Lin; Shu, Xiao-Ning; Liang, Dong; Wang, Cong

    2014-07-01

    Significance of this study lies in tungsten nano materials can be used as a preliminary innovative medicines applied basic research. This paper investigated the inhibition of tungsten nanoparticles which effected on human hepatoma HepG2 cells by MTT. The authors use transient absorption spectroscopy (TAS) technology absorption and emission spectra characterization of charge transfer between nanoparticles and tumor cell. The authors discussed the role of the tungsten nanoparticles in the tumor early detection of the disease and its anti-tumor properties. In the HepG2 experiments system, 100-150 microg x mL(-1) is the best drug concentration of anti-tumor activity which recact violently within 6 hours and basically completed in 24 hours. The results showed that transient absorption spectroscopy can be used as tumor detection methods and characterization of charge transfer between nano-biosensors and tumor cells. Tungsten nanoparticles have potential applications as anticancer drugs.

  1. Preliminary Study on Airlift Membran—Bioreactor

    Institute of Scientific and Technical Information of China (English)

    XUNong; XINGWeihong; 等

    2002-01-01

    A new type of membrane bioreactor named “airlift membrane-bioreactor”is discussed.For municipal wastewater reclamation,the preliminary study on airlift membrane-bioreactor shows its good performance such as high flux and lower energy consumption.The airlift membrane-bioreactor is potentially applicable in bioengineering and environmental protection fields.

  2. Spiral 2: preliminary design study

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-11-15

    The scientific council of GANIL asked to perform a comparative study on the production methods based on gamma induced fission and rapid-neutron induced fission concerning the nature and the intensity of the neutron-rich products. The production rate expected should be around 10{sup 13} fissions per second. The study should include the implantation and the costs of the concerned accelerators. The scientific committee recommended also to study the possibility to re-inject the radioactive beams of SPIRAL-II in the cyclotrons available at GANIL in order to give access to an energy range from 1.7 to 100 MeV/nucleon. For that purpose, some study groups have been formed to evaluate the possibility of such a project in the different components: physics case, target-ion sources, drivers, post-acceleration and general infrastructure. The organization of the project study is given at the end of this report. The following report presents an overview of the study. Particularly the total costs have been assessed according to 3 options for the driver: 38.0*10{sup 6} euros for a 40 MeV deuteron linac, 18.7*10{sup 6} euros for a 45 MeV electron linac, and 29.1*10{sup 6} euros for a 80 MeV deuteron cyclotron.

  3. Institutional Repositories in India: A preliminary study

    OpenAIRE

    2011-01-01

    This preliminary study investigates various aspects of institutional repositories (IR’s) developed in India. The present study has identified the existence of 16 functional IRs some of which were not registered in any of the directories such as ROAR, Open DOAR. The study explores the timeline involved in planning, pilot testing, to system implementation of IR, exploratory activities conducted before implementing IR, its anticipated benefits.

  4. Worker Motivation Study: Preliminary Analysis.

    Science.gov (United States)

    Fulton, Margaret A.

    Since the Hawthorne Studies gave birth to the human relations approach to management, employee motivation, defined as an intervening variable(s) that accounts for factors within an individual that arouse, maintain, and channel behavior toward a goal, has been of much interest. An attempt was made to replicate the factor structure of the Wherry and…

  5. preliminary study of American legal culture

    Institute of Scientific and Technical Information of China (English)

    周杨

    2016-01-01

    This thesis is a preliminary study of American legal culture. Nowadays more and more scholars see the importance of legal culture and do studies on it. The author selects a number of American legal TV plays and movies; analyzes their topics, main characters, and plots; then finds out why United States adopt the legal system; what kind of legal culture it has; and how the legal culture is reflected in those movies and TV plays. The author hopes this thesis can work not only as an insight into the American legal culture, but also a source of reference for china to improve its legal system.

  6. Transient critical heat flux and blowdown heat-transfer studies

    Energy Technology Data Exchange (ETDEWEB)

    Leung, J.C.

    1980-05-01

    Objective of this study is to give a best-estimate prediction of transient critical heat flux (CHF) during reactor transients and hypothetical accidents. To accomplish this task, a predictional method has been developed. Basically it involves the thermal-hydraulic calculation of the heated core with boundary conditions supplied from experimental measurements. CHF predictions were based on the instantaneous ''local-conditions'' hypothesis, and eight correlations (consisting of round-tube, rod-bundle, and transient correlations) were tested against most recent blowdown heat-transfer test data obtained in major US facilities. The prediction results are summarized in a table in which both CISE and Biasi correlations are found to be capable of predicting the early CHF of approx. 1 s. The Griffith-Zuber correlation is credited for its prediction of the delay CHF that occurs in a more tranquil state with slowly decaying mass velocity. In many instances, the early CHF can be well correlated by the x = 1.0 criterion; this is certainly indicative of an annular-flow dryout-type crisis. The delay CHF occurred at near or above 80% void fraction, and the success of the modified Zuber pool-boiling correlation suggests that this CHF is caused by flooding and pool-boiling type hydrodynamic crisis.

  7. Transient global amnesia and neurological events: the Framingham Heart Study

    Directory of Open Access Journals (Sweden)

    Jose Rafael Romero

    2013-05-01

    Full Text Available Background/ objective: Transient global amnesia (TGA is a temporary amnestic syndrome characterized by lack of other focal neurological deficits. Cerebrovascular disease, migraine and seizures have been suggested as underlying mechanisms. TGA may be a risk factor for cerebrovascular or other neurological events. We studied the relation of TGA, vascular risk factors, brain magnetic resonance imaging (MRI indices of subclinical ischemia and neurological events in a community-based sample. Design/setting: A total of 12 TGA cases were ascertained using standard criteria by experienced neurologists, and matched to 41 stroke- and seizure-free controls. Vascular risk factors, brain MRI findings, and subsequent cerebrovascular or seizure events were compared in cases and controls. Participants: Framingham Heart Study (FHS original and offspring cohort participants were included.Results: No significant differences between the groups were observed in the prevalence of vascular risk factors, or brain MRI measures. Few incident stroke/transient ischemic attacks (TIA (1 event among the cases and 4 in controls or subsequent seizures occurred in either group. Head CT during the acute event (n=11 and brain MRI (n=7 were negative for acute abnormalities. Electroencephalograms (EEG (n=5 were negative for epileptiform activity. Extracranial vascular studies were negative for significant stenosis in all cases.Conclusions: In our community-based study TGA was not related to traditional vascular risk factors, or cerebrovascular disease. However, our study is limited by small sample size and power, and larger studies are required to exclude an association.

  8. Experimental studies of the transient fluctuation theorem using liquid crystals

    Indian Academy of Sciences (India)

    Soma Datta; Arun Roy

    2009-05-01

    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.

  9. A preliminary neutron crystallographic study of thaumatin

    Energy Technology Data Exchange (ETDEWEB)

    Teixeira, Susana C. M. [ILL-EMBL Deuteration Laboratory, Partnership for Structural Biology, 6 Rue Jules Horowitz, 38042 Grenoble (France); Institut Laue Langevin, 6 Rue Jules Horowitz, 38042 Grenoble (France); EPSAM and ISTM, Keele University, Staffordshire ST5 5BG (United Kingdom); Blakeley, Matthew P. [Institut Laue Langevin, 6 Rue Jules Horowitz, 38042 Grenoble (France); Leal, Ricardo M. F. [ILL-EMBL Deuteration Laboratory, Partnership for Structural Biology, 6 Rue Jules Horowitz, 38042 Grenoble (France); Institut Laue Langevin, 6 Rue Jules Horowitz, 38042 Grenoble (France); EPSAM and ISTM, Keele University, Staffordshire ST5 5BG (United Kingdom); ESRF, 6 Rue Jules Horowitz, BP-220, 38043 Grenoble (France); Mitchell, Edward P. [EPSAM and ISTM, Keele University, Staffordshire ST5 5BG (United Kingdom); ESRF, 6 Rue Jules Horowitz, BP-220, 38043 Grenoble (France); Forsyth, V. Trevor, E-mail: tforsyth@ill.fr [ILL-EMBL Deuteration Laboratory, Partnership for Structural Biology, 6 Rue Jules Horowitz, 38042 Grenoble (France); Institut Laue Langevin, 6 Rue Jules Horowitz, 38042 Grenoble (France); EPSAM and ISTM, Keele University, Staffordshire ST5 5BG (United Kingdom)

    2008-05-01

    Preliminary neutron crystallographic data from the sweet protein thaumatin have been recorded using the LADI-III diffractometer at the Institut Laue Langevin (ILL). The results illustrate the feasibility of a full neutron structural analysis aimed at further understanding the molecular basis of the perception of sweet taste. Such an analysis will exploit the use of perdeuterated thaumatin. A preliminary neutron crystallographic study of the sweet protein thaumatin is presented. Large hydrogenated crystals were prepared in deuterated crystallization buffer using the gel-acupuncture method. Data were collected to a resolution of 2 Å on the LADI-III diffractometer at the Institut Laue Langevin (ILL). The results demonstrate the feasibility of a full neutron crystallographic analysis of this structure aimed at providing relevant information on the location of H atoms, the distribution of charge on the protein surface and localized water in the structure. This information will be of interest for understanding the specificity of thaumatin–receptor interactions and will contribute to further understanding of the molecular mechanisms underlying the perception of taste.

  10. A clinicopathologic study of transient osteoporosis of the hip

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, Takuaki; Noguchi, Yasuo; Iwamoto, Yukihide [Dept. of Orthopaedic Surgery, Faculty of Medicine, Kyushu University, Fukuoka (Japan); Kubo, Toshikazu; Hirasawa, Yasusuke [Dept. of Orthopaedic Surgery, Kyoto Prefectural University of Medicine, Kyoto (Japan); Sueishi, Katsuo [Dept. of Pathology, Faculty of Medicine, Kyushu University, Fukuoka (Japan)

    1999-11-01

    Objective. It has been proposed that transient osteoporosis of the hip (TOH) may represent the early reversible phase of osteonecrosis of the femoral head (ON). The purpose of this study was to investigate the clinicopathologic characteristics of three cases of TOH.Design and patients. A bone biopsy was performed on three patients who had been diagnosed as having TOH based on the clinical course, radiograph, bone scintigram, and MR images. The biopsy specimens were studied histopathologically by light and electron microscopy.Results. The most characteristic feature of TOH was focal areas of thin and disconnected bone trabeculae covered by osteoid seams and active osteoblasts. The surrounding bone marrow tissue showed edematous changes and mild fibrosis, frequently associated with vascular congestion and/or interstitial hemorrhage. No osteonecrotic region was observed in either the bone trabeculae or the bone marrow tissue. All patients have improved clinically and in the 3.5-9 years of follow-up have shown no evidence of ON.Conclusions. This study supports the concept that transient osteoporosis of the hip is a distinct entity. (orig.)

  11. Transient grating study of the intermolecular dynamics of liquid nitrobenzene

    Science.gov (United States)

    Wu, Hong-Lin; Song, Yun-Fei; Yu, Guo-Yang; Yang, Yan-Qiang

    2016-10-01

    Femtosecond time-resolved transient grating (TG) technique is used to study the intermolecular dynamics in liquid phase. Non-resonant excitation of the sample by two crossing laser pulses results in a transient Kerr grating, and the molecular motion of liquid can be detected by monitoring the diffraction of a third time-delayed probe pulse. In liquid nitrobenzene (NB), three intermolecular processes are observed with lifetimes of 37.9±1.4 ps, 3.28±0.11 ps, and 0.44±0.03 ps, respectively. These relaxations are assigned to molecular orientational diffusion, dipole/induced dipole interaction, and libration in liquid cage, respectively. Such a result is slightly different from that obtained from OKE experiment in which the lifetime of the intermediate process is measured to be 1.9 ps. The effects of electric field on matter are different in TG and optical Kerr effect (OKE) experiments, which should be responsible for the difference between the results of these two types of experiments. The present work demonstrates that TG technique is a useful alternative in the study of intermolecular dynamics. Project supported by the National Natural Science Foundation of China (Grant Nos. 11304058 and 11404307) and NSAF (Grant No. U1330106).

  12. Preliminary study of radium-contaminated soils

    Energy Technology Data Exchange (ETDEWEB)

    Healy, J.W.; Rodgers, J.C.

    1978-10-01

    A preliminary study was made of the potential radiation exposures to people from radium-226 contamination in the soil in order to provide guidance on limits to be applied in decontaminating land. Pathways included were inhalation of radium from resuspension; ingestion of radium with foods; external gamma radiation from radium daughters; inhalation of radon and daughter, both in the open air and in houses; and the intake of /sup 210/Pb and /sup 210/Po from both inhalation and ingestion. The depth of the contaminated layer is of importance for external exposure and especially for radon emanation. The most limiting pathway was found to be emanation of the radon into buildings with limiting values comparable to those found naturally in many areas.

  13. Impromptu Speaking and Interpretation Studies: A Preliminary Study

    Science.gov (United States)

    Heinz, Michael

    2013-01-01

    The purpose of this preliminary study was to look at forensics-based competition events and determine what, if any, impact they could have on the language learning and public speaking skills of interpreters in training. This paper details the nature of the impromptu and extemporaneous speaking events in forensics competitions and introduces a…

  14. Impromptu Speaking and Interpretation Studies: A Preliminary Study

    Science.gov (United States)

    Heinz, Michael

    2013-01-01

    The purpose of this preliminary study was to look at forensics-based competition events and determine what, if any, impact they could have on the language learning and public speaking skills of interpreters in training. This paper details the nature of the impromptu and extemporaneous speaking events in forensics competitions and introduces a…

  15. Studi Karakteristik Kopling Plat Gesek Tunggal Pada Kondisi Transient

    Directory of Open Access Journals (Sweden)

    Joni Dewanto

    2002-01-01

    Full Text Available In the trannsient state both of the friction plates of clutch are not yet fully connected so the power is transmited by kinetic friction force. This force change depend on normal and their kinetic friction. For maintain the speed and power of vehicle the clutch is often operated in the transient state because in this state the engine revolution can be increased. Study about this characteritics is done by an experiment and theoritical analysis on a single friction plate clutch model. The experiment variable consist of load, speed of revolution and normal pressing force. The result of this analysis shows that the torsion and power is increase linearly when the relatif speed of revolution increace. Because higher speed produce higher heat on friction plat so the the kinetic friction coeffisien is increase too. Abstract in Bahasa Indonesia : Pada kondisi transient kedua plat gesek kopling belum menempel sepenuhnya sehingga pemindahan daya terjadi karena gaya gesek kinetik. Gaya ini berubah tergantung dari normal dan koefisien gaseknya. Kopling sering dioperasikan pada kondisi transien untuk menjaga laju dan tenaga kendaraan karena dalam kondisi ini putaran mesin dapat ditingkatkan. Studi tentang karekteristik tersebut dilakukan dengan membuat sebuah kajian teoritik dan eksperimen dan menggunakan model uji sebuah kopling gesek plat tunggal. Variabel pengujian meliputi beban, kecepatan putar dan gaya normal penekanan. Hasil kajian ini menunjukkan bahwa terjadi kenaikan torsi dan daya secara linear pada kecepatan putar relatif yang makin tinggi. Hal ini disebabkan karena makin tingginya kecepatan akan menimbulkan panas yang makin tinggi pada plat gesek sehingga besarnya koefisien gesek meningkat. Kata kunci: kopling gesek, dry friction.

  16. Preliminary study natural gas; Foerstudie naturgas

    Energy Technology Data Exchange (ETDEWEB)

    Lamnevik, Stefan; Carlsson, Tomas; Dyhr, Kurt

    2000-09-01

    FOA has carried out a preliminary study on natural gas for the Swedish National Energy Administration. To use natural gas as an energy source could be one step towards use of carbon-free fuels such as hydrogen. Natural gas, consisting mainly of methane, is the hydrocarbon with the highest hydrogen content. It has a high heat of combustion, 55 MJ/kg, and a low emission of carbon dioxide, 2.8 kg/kg fuel or 0.051 kg/MJ. The carbon dioxide emission per energy unit is twice as high for coal, 75% higher for wood fuels, and 27% higher for fuel oils. The Swedish natural gas network starts at Malmoe and ends at Hyltebruk. The natural gas used is imported from Denmark by Sydgas AB. It would be possible in the future to get connections to the Russian and the Norwegian networks and also to import LNG by ship and store it to buffer the different consumption demands during summer and winter. Natural gas is non-toxic but can be suffocating due to too low oxygen content at high concentrations. Combustion with an inadequate air supply will form toxic carbon monoxide like other carbonaceous fuels. Natural gas/air mixtures may explode like other gaseous fuels. The gas is lighter than air and is therefore dispersed better than heavier gases like LPG. Natural gas is difficult to detonate unlike other gases.

  17. Advanced simulation study on bunch gap transient effect

    Science.gov (United States)

    Kobayashi, Tetsuya; Akai, Kazunori

    2016-06-01

    Bunch phase shift along the train due to a bunch gap transient is a concern in high-current colliders. In KEKB operation, the measured phase shift along the train agreed well with a simulation and a simple analytical form in most part of the train. However, a rapid phase change was observed at the leading part of the train, which was not predicted by the simulation or by the analytical form. In order to understand the cause of this observation, we have developed an advanced simulation, which treats the transient loading in each of the cavities of the three-cavity system of the accelerator resonantly coupled with energy storage (ARES) instead of the equivalent single cavities used in the previous simulation, operating in the accelerating mode. In this paper, we show that the new simulation reproduces the observation, and clarify that the rapid phase change at the leading part of the train is caused by a transient loading in the three-cavity system of ARES. KEKB is being upgraded to SuperKEKB, which is aiming at 40 times higher luminosity than KEKB. The gap transient in SuperKEKB is investigated using the new simulation, and the result shows that the rapid phase change at the leading part of the train is much larger due to higher beam currents. We will also present measures to mitigate possible luminosity reduction or beam performance deterioration due to the rapid phase change caused by the gap transient.

  18. Study of Transients in an Enrichment Closed Loop

    CERN Document Server

    Fernandino, M

    2002-01-01

    In the present thesis a mathematic model is presented in order to describe the dynamic behavior inside a closed enrichment loop, the latter representing a single stage of an uranium gaseous diffusion enrichment cascade.The analytical model is turned into a numerical model, and implemented through a computational code.For the verification of the model, measurements were taken in an experimental circuit using air as the process fluid.This circuit was instrumented so as to register its characteristic thermohydraulic variables.The measured transients were simulated, comparing the numerical results with the experimental measurements.A good agreement between the characteristic setting times and the thermohydraulic parameters evolution was observed.Besides, other transients of two species separation were numerically analyzed, including setting times of each magnitude, behavior of each one of them during different transients, and redistribution of concentrations.

  19. A biogeographic study of intermountain leeches : Preliminary report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Preliminary report for a five year study on leeches in the intermountain west. This work began out of curiosity to determine what, besides fishes, occurred in the...

  20. Dynamics in photosynthetic transient complexes studied by paramagnetic NMR spectroscopy

    NARCIS (Netherlands)

    Scanu, Sandra

    2013-01-01

    This PhD thesis focuses on fundamental aspects of protein-protein interactions. A multidisciplinary methodology for the detection and visualization of transient, lowly-populated encounter protein complexes is described. The new methodology combined paramagnetic NMR spectroscopy with computational

  1. Preliminary Study of Realistic Blast Impact on Cultured Brain Slices

    Science.gov (United States)

    2015-04-01

    hippocampal slice samples to better understand blast-induced brain damage. 15. SUBJECT TERMS RDX spheres , organotypic cultures of hippocampus, small...Preliminary Study of Realistic Blast Impact on Cultured Brain Slices by Thuvan Piehler, Rohan Banton, Lars Piehler, Richard Benjamin, Ray...Aberdeen Proving Ground, MD 21005-5066 ARL-TR-7197 April 2015 Preliminary Study of Realistic Blast Impact on Cultured Brain Slices Thuvan

  2. Isolated Ti in Si: Deep level transient spectroscopy, minority carrier transient spectroscopy, and high-resolution Laplace deep level transient spectroscopy studies

    Science.gov (United States)

    Scheffler, L.; Kolkovsky, Vl.; Weber, J.

    2015-01-01

    Combining deep level transient spectroscopy (DLTS), high-resolution Laplace DLTS, and minority carrier transient spectroscopy studies, we question the identification of the dominant Ti-related defects introducing deep levels (E40, E150, and H180) in n- and p-type Si. The observed results cannot unambiguously support the models previously reported for these defects. The presence of the Poole-Frenkel effect describing the enhancement of the emission rates of E40 as a function of electric field is not consistent with the previous assignment of this defect to the single acceptor, whereas the absence of the enhancement of the emission rate of E150 under different reverse bias applied to the diode does not confirm the previous attribution of this defect to the single donor in n-type Si. The attribution of H180 to the double donor is in good agreement with our results. In contrast, the identical depth profiles obtained for E40 and E150 in bulk of as-grown, hydrogenated and annealed samples cannot be explained by the assignment of these levels to different defects.

  3. Preliminary analysis of selected gas dynamic problems. [space shuttle main engine main combustion transients and IUS nozzle flow

    Science.gov (United States)

    Prozan, R. J.; Farmer, R. C.

    1985-01-01

    The VAST computer code was used to analyze SSME main combustion chamber start-up transients and the IUS flow field for a damaged nozzle was investigated to better understand the gas dynamic considerations involved in vehicle problems, the effect of start transients on the nozzle flow field for the SSME, and the possibility that a damaged nozzle could account for the acceleration anomaly noted on IUS burn. The results obtained were compared with a method of characteristics prediction. Pressure solutions from both codes were in very good agreement and the Mach number solution on the nozzle centerline deviates substantially for the high expansions for the SSME. Since this deviation was unexpected, the phenomenon is being further examined.

  4. CdTe Nanowires studied by Transient Absorption Microscopy

    Directory of Open Access Journals (Sweden)

    Kuno M.

    2013-03-01

    Full Text Available Transient absorption measurements were performed on single CdTe nanowires. The traces show fast decays that were assigned to charge carrier trapping at surface states. The observed power dependence suggests the existence of a trap-filling mechanism. Acoustic phonon modes were also observed, which were assigned to breathing modes of the nanowires. Both the fundamental breathing mode and the first overtone were observed, and the dephasing times provide information about how the nanowires interact with their environment.

  5. An Experimental Study of the Flowrate Transients in Slug Flow

    Institute of Scientific and Technical Information of China (English)

    HELimin; CHENZhenyu; 等

    2002-01-01

    An investigation of the characteristics of flowrate transients within slug flow was conducted in a largescale outdoor testing facility.The test section consisted of a 378m long,7.62cm diameter stainless steel pipe. Air and water were used as the test fluids.The response to a change of flowrate o either phase or two phases was measured using a series of pressure transducers and differential pressure transducers.An increase or decrease in gas flowrate caused a pressure overshoot above the value at new steady state or led to a pressure undershoot to form a temporary stratified flow.Pressure waves existed in the pipeline,spreading from the entrance to the exit.The magnitude of pressure overshoot in “up-gas”transient or of pressure undershoot and period of the temporary stratified flow in “Down-gas” transient are related to the change of gas flowrate and the distance away from the entrance.In contrast,the change in liquid flowrate was accommodated by smooth transitions between the corresponding steady states,and only one obvious change was found in the slug frequency.According to experimental results,the pressure overshoot,pressure undershoot and the pressure wave propagation were analyzed,and the phenomena were explained reasonably.Some correlations for the calculation of the pressure overshoot and undershoot were proposed.

  6. Primary study on imaging in transient ischemic attacks

    Institute of Scientific and Technical Information of China (English)

    LU Jie; LI Kun-cheng; HUA Yang

    2005-01-01

    Background Although transient ischemic attacks (TIA) is a clinical diagnosis, imaging findings are important for its diagnosis and treatment. This study evaluated the value and limitations of conventional CT, CT cerebral perfusion imaging and transcranial Doppler sonography (TCD) in patients with TIA.Methods Conventional CT, CT cerebral perfusion imaging and TCD were performed in 20 patients with TIA. After regular CT examination, 40-second dynamic scans were performed on selected slice, while 40 ml of non-ionic contrast materials was bolus-injected through antecubital vein with power injector. These dynamic images were processed with the perfusion software package on workstation. Cerebral blood flow (CBF) and time to peak (TTP) were measured in specific regions of the brain. TCD was also performed in 20 patients with TIA. Comparative analysis was made on the basis of the results of conventional CT, CT cerebral perfusion imaging and TCD. Results In the 20 patients with TIA, conventional CT turned out to be normal. However, persisting abnormal perfusion changes corresponding to clinical symptoms were found in 13 cases with the prolonged TTP. The other 7 cases were normal. TTP of the affected side (11.6±3.0)s was significantly prolonged (t=4.782,P<0.01) in comparison with the contralateral side (8.8±1.5)s. The difference in CBF was not statistically significant (t=1.912, P=0.073) between the affected side [(223.9±19.6) ml*min-1*L-1] and the contralateral side [(227.7±19.8) ml*min-1*L-1] . TCD revealed severe stenosis or occlusion of the carotid artery in 10 patients, arteriosclerosis in 6 patients, blood speed decrease in 2 patients, vasospasm in 1 patient. Conclusions Conventional CT can exclude intracerebral diseases. Perfusion CT provides valuable hemodynamic information and shows the extent of perfusion disturbances. TCD can demonstrate abnormalities of the involved arteries in patients with TIA. The combination of these three imaging methods can provide more

  7. Experimental and theoretical study on rapid transient nucleated boiling

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A laser heater has been used to impose a pulsed high power laser beam on a metal film inunersed in liquid to generate a very high rate of temperature rise up to 9.3 × 106K/s in the metal film. The rapid transient boiling phenomena have been observed and the temperature variations in the metal film have been measured. Theoretical calculations have been carried out with the fluctuation nucleation theory and the heat conduction theory to compare with the experimental results, and some results are reported.

  8. Study of new optical transients using 3.6m DOT at Devasthal Nainital

    Science.gov (United States)

    Pandey, S. B.

    2016-12-01

    Longitudinal advantage of Indian sub-continent makes the recently installed 3.6m telescope as a novel facility for astronomical observations, specially, to study time critical events, i.g. transients. This telescope along with the first generation back-end instruments could be efficiently used to study new transients discovered using a global network of robotic survey telescopes. Study of new transients as a part of time domain astronomy will play a key role in near future along with the upcoming multi-wavelength facilities to explore the underlying physics behind these sources.

  9. Study on transient aerodynamic characteristics of parachute opening process

    Institute of Scientific and Technical Information of China (English)

    Li Yu; Xiao Ming

    2007-01-01

    In the research of parachute, canopy inflation process modeling is one of the most complicated tasks. As canopy often experiences the largest deformations and loa-dings during a very short time, it is of great difficulty for theoretical analysis and experimental measurements. In this paper, aerodynamic equations and structural dynamics equa-tions were developed for describing parachute opening process, and an iterative coupling solving strategy incorpo-rating the above equations was proposed for a small-scale, flexible and flat-circular parachute. Then, analyses were car-ried out for canopy geometry, time-dependent pressure diffe-rence between the inside and outside of the canopy, transient vortex around the canopy and the flow field in the radial plane as a sequence in opening process. The mechanism of the canopy shape development was explained from perspective of transient flow fields during the inflation process. Experi-ments of the parachute opening process were conducted in a wind tunnel, in which instantaneous shape of the canopy was measured by high velocity camera and the opening loading was measured by dynamometer balance. The theoretical pre-dictions were found in good agreement with the experimen-tal results, validating the proposed approach. This numerical method can improve the situation of strong dependence of parachute research on wind tunnel tests, and is of signifi-cance to the understanding of the mechanics of parachute inflation process.

  10. Preliminary studies of a new accelerator-driven minor actinide burner in industrial scale

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xunzhao; Zhou, Shengcheng [School of Nuclear Science and Technology, Xi’an Jiaotong University, Xi’an 710049, Shaanxi (China); Zheng, Youqi, E-mail: yqzheng@mail.xjtu.edu.cn [School of Nuclear Science and Technology, Xi’an Jiaotong University, Xi’an 710049, Shaanxi (China); Wang, Kunpeng [Nuclear and Radiation Safety Center, PO Box 8088, No. 54, Beijing 100082 (China); Wu, Hongchun [School of Nuclear Science and Technology, Xi’an Jiaotong University, Xi’an 710049, Shaanxi (China)

    2015-10-15

    Highlights: • A new accelerator-driven minor actinide (MA) burner was proposed. • Comprehensive design of spallation target, fuel assembly and subcritical core was performed. • Preliminary safety analyses indicate the inherent safety of the core in the reactivity insertion (500 pcm) and beam overpower (50% increase) transients. - Abstract: Pursuing high transmutation rate of minor actinide (MA), a preliminary conceptual design of a lead-bismuth (LBE) cooled accelerator-driven system (ADS) is proposed in this study. Parametric studies are performed to optimize the neutronics and thermal–hydraulics performances. The proton energy and axial position of the proton beam impact is investigated to obtain high neutron source efficiency and spallation neutron yield. The influences of MA/Pu mixing ratio and the ratio of pin pitch to diameter (P/D) are also optimized to control the burnup reactivity swing and the minimum coolant velocity for adequate cooling. To reduce the power peak, three kinds of power flattening techniques are adopted and compared. The results show that the inert matrix ratio zone loading method seems more versatile. Based on the analyses, an optimized three zone loading pattern is proposed for the 800 MWth subcritical core. The total transmutation rate of MA is 328.8 kg per effective full power year. Preliminary safety analyses based on the balance of power method (BOP) are performed and the results show that in the reactivity insertion and beam overpower transients, the core shows inherent safety, but the scram is necessary by cutting off the beam current to protect the core from possible damages caused by the loss of flow.

  11. Study on a transient optical fiber high temperature measurement system

    Science.gov (United States)

    Cai, Lulu; Liu, Yusha; Wang, Yutian

    2009-07-01

    High temperature is one of the most important parameters in the fields of scientific research and industrial production. At present, thermocouple, thermo resistive and radiance thermometer are already technologically mature which can be adopted to measure the general temperature, but when it comes to the transient high temperature that changes pretty quickly in wretched conditions, those traditional pyrometers can not meet the requirements any more. In this paper, we designed a transient optical high temperature measurement system. First, design of the temperature measurement probe. The system took blackbody cavity sensor together with optical fiber to receive the measured signal, here, the integrated emissivity model of the blackbody cavity was established and the optimum structure parameters were confirmed. Secondly, design of the entire temperature measurement system. A contact-noncontact measurement method was applied, which is to make the blackbody cavity and the measured high-temperature source contact, the fiber probe and the blackbody cavity noncontact, as a result, the error caused by contact measurement is overcame and the precision is guaranteed at the same time. In addition, a fiber grating was introduced as the wavelength filter device which can realize the dynamic filter of narrow-band signals and reduce the impact of background light. Thirdly, signal processing. In this part, we applied labVIEW software and wavelet analysis method. All of the signal acquisition and processing were realized in the labVIEW environment. Through calling matlab in labVIEW, the signals from optical fiber detector were wavelet denoised and decomposed, thus the temperature information was extracted, and the temperature value was obtained. On basis of wavelet transformation, the paper adopted the 4dB wavelet with horizontal scale of 5 to realize the feature extraction and noise removal, parts of the signals before and after the wavelet noise removal were given and analyzed

  12. The simulation of transient statistics of the Southern Hemispheric circulation by the GLAS seasonal cycle model: Preliminary results

    Science.gov (United States)

    Straus, D. M.; Shukla, J.

    1984-01-01

    The general circulation of the Southern Hemisphere is quite different from that of the Northern Hemisphere in many important ways. These include the barotropic nature of the stationary waves and the presence of a strong barotropic component to the mean zonal wind, the lack of a strong seasonal dependence of the transient eddies, and the dominant role played by eddies with periods less than 10 days compared to longer period fluctuations. Such differences attest to the importance of the altered nature of the orographic and thermal land-sea forcings in the Southern Hemisphere compared to the Northern Hemisphere. Some of the important features of the Southern Hemisphere circulation as simulated by the GLAS Seasonal Cycle Model (SCM) are presented. The geographical patterns of local variability and their seasonal shifts in the SCM are discussed and compared to observations.

  13. Washington DC Metropolitan Area Drug Study Homeless and Transient Population (DC-MADST-1991)

    Data.gov (United States)

    U.S. Department of Health & Human Services — The DC Metropolitan Area Drug Study (DCMADS) was conducted in 1991, and included special analyses of homeless and transient populations and of women delivering live...

  14. Spring Transient Count: Additions to the Approved Research/Management Study Proposal

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The purpose of this study is to determine the relative abundances of migrating transient birds in the different habitat types of St. Vincent Island; to determine...

  15. The effect of chemotherapy on rat brain PET: preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jin Su; Kim, Il Han; Yu, A Ram; Park, Ji Ae; Woo, Sang Keun; Kim, Jong Guk; Cheon, Gi Jeong; Kim, Byeong Il; Choi, Chang Woon; Lim, Sang Moo; Kim, Hee Joung; Kim, Kyeong Min [Korea Institute Radiological and Medical Science, Seoul (Korea, Republic of)

    2010-10-15

    Chemotherapy was widely used for the therapy of cancer patients. When chemotherapy was performed, transient cognitive memory problem was occurred. This cognitive problem in brain was called as chemobrain. In this study, we have developed rat model for chemobrain. Cerebral glucose metabolism after chemotherapy was assessed using animal PET and voxel based statistical analysis method

  16. TRANSIENT ELECTRONICS CATEGORIZATION

    Science.gov (United States)

    2017-08-24

    definitions of what it means to be transient. The purpose of this technical report is to provide a background of the issues related to transient...In this section, we will attempt to identify these parameters and provide preliminary definitions for categories of transience behavior. Transient...programmable lifetimes. Ideally , such materials with expiration dates will deconstruct themselves into harmless and invisible remnants. The technology base

  17. Modular endoprosthesis for mandibular reconstruction: a preliminary animal study.

    NARCIS (Netherlands)

    Lee, S.; Goh, B.T.; Tideman, H.; Stoelinga, P.J.W.

    2008-01-01

    The use of a mandibular modular endoprosthesis after segmental resection of part of the body of the mandible was studied. This preliminary study was carried out on four pigs and four monkeys. The devices were made of a titanium alloy and were cemented in the prepared medullary spaces with polymethyl

  18. Interfacial Electron Transfer and Transient Photoconductivity Studied with Terahertz Spectroscopy

    Science.gov (United States)

    Milot, Rebecca Lee

    Terahertz spectroscopy is distinguished from other far infrared and millimeter wave spectroscopies by its inherent phase sensitivity and sub-picosecond time resolution making it a versatile technique to study a wide range of physical phenomena. As THz spectroscopy is still a relatively new field, many aspects of THz generation mechanisms have not been fully examined. Using terahertz emission spectroscopy (TES), THz emission from ZnTe(110) was analyzed and found to be limited by two-photon absorption and free-carrier generation at high excitation fluences. Due to concerns about the continued use of fossil fuels, solar energy has been widely investigated as a promising source of renewable energy. Dye-sensitized solar cells (DSSCs) have been developed as a low-cost alternative to conventional photovoltaic solar cells. To solve the issues of the intermittency and inefficient transport associated with solar energy, researchers are attempting to adapt DSSCs for water oxidation and chemical fuel production. Both device designs incorporate sensitizer molecules covalently bound to metal oxide nanoparticles. The sensitizer, which is comprised of a chromophore and anchoring group, absorbs light and transfers an electron from its excited state to the conduction band of the metal oxide, producing an electric current. Using time-resolved THz spectroscopy (TRTS), an optical pump/THz probe technique, the efficiency and dynamics of electron injection from sensitizers to metal oxides was evaluated as a function of the chromophore, its anchoring group, and the metal oxide identity. Experiments for studying fully functioning DSSCs and water oxidation devices are also described. Bio-inspired pentafluorophenyl porphyrin chromophores have been designed and synthesized for use in photoelectrochemical water oxidation cells. Influences on the efficiency and dynamics of electron injection from the chromophores into TiO2 and SnO2 nanoparticles due to changes in both the central substituent to

  19. Deep level study of Mg-doped GaN using deep level transient spectroscopy and minority carrier transient spectroscopy

    Science.gov (United States)

    Duc, Tran Thien; Pozina, Galia; Amano, Hiroshi; Monemar, Bo; Janzén, Erik; Hemmingsson, Carl

    2016-07-01

    Deep levels in Mg-doped GaN grown by metal organic chemical vapor deposition (MOCVD), undoped GaN grown by MOCVD, and halide vapor phase epitaxy (HVPE)-grown GaN have been studied using deep level transient spectroscopy and minority charge carrier transient spectroscopy on Schottky diodes. One hole trap, labeled HT1, was detected in the Mg-doped sample. It is observed that the hole emission rate of the trap is enhanced by increasing electric field. By fitting four different theoretical models for field-assisted carrier emission processes, the three-dimensional Coulombic Poole-Frenkel (PF) effect, three-dimensional square well PF effect, phonon-assisted tunneling, and one-dimensional Coulombic PF effect including phonon-assisted tunneling, it is found that the one-dimensional Coulombic PF model, including phonon-assisted tunneling, is consistent with the experimental data. Since the trap exhibits the PF effect, we suggest it is acceptorlike. From the theoretical model, the zero field ionization energy of the trap and an estimate of the hole capture cross section have been determined. Depending on whether the charge state is -1 or -2 after hole emission, the zero field activation energy Ei 0 is 0.57 eV or 0.60 eV, respectively, and the hole capture cross section σp is 1.3 ×10-15c m2 or 1.6 ×10-16c m2 , respectively. Since the level was not observed in undoped GaN, it is suggested that the trap is associated with an Mg related defect.

  20. First airborne transient em survey in antarctica

    DEFF Research Database (Denmark)

    Auken, Esben; Mikucki, J. J.; Sørensen, Kurt Ingvard K.I.

    2012-01-01

    conductive targets, and the transient AEM method provides a better understanding of the saline ground water system for microbiology, paleoclimate studies, or geothermal potential. In this study we present preliminary results from our field survey which resulted in more than 1000 km of flight lines...

  1. Model Fidelity Study of Dynamic Transient Loads in a Wind Turbine Gearbox: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Y.; Keller, J.; Moan, T.; Xing, Y.

    2013-04-01

    Transient events cause high loads in the drivetrain components so measuring and calculating these loads can improve confidence in drivetrain design. This paper studies the Gearbox Reliability Collaborative 750kW wind turbine gearbox response during transient events using a combined experimental and modeling approach. The transient events include emergency shut-downs and start-ups measured during a field testing period in 2009. The drivetrain model is established in the multibody simulation tool Simpack. A detailed study of modeling fidelity required for accurate load prediction is performed and results are compared against measured loads. A high fidelity model that includes shaft and housing flexibility and accurate bearing stiffnesses is important for the higher-speed stage bearing loads. Each of the transient events has different modeling requirements.

  2. Wide-field monitoring strategy for the study of fast optical transients

    Science.gov (United States)

    Beskin, Grigory; Bondar, Sergey; Karpov, Sergey; Guarnieri, Adriano; Bartolini, Corrado; Greco, Giuseppe; Piccioni, Adalberto

    2010-10-01

    We discuss the strategy of search for fast optical transients accompanying gamma-ray bursts by means of continuous monitoring of wide sky fields with high temporal resolution. We describe the design, performance and results of our cameras, FAVOR and TORTORA. Also we discuss the perspectives of this strategy and possible design of next-generation equipment for wide-field monitoring which will be able to detect optical transients and to study their color and polarization properties with high time resolution.

  3. A New Silver Complex with Ofloxacin – Preliminary Study

    Directory of Open Access Journals (Sweden)

    Rusu Aura

    2016-06-01

    Full Text Available Objective: Silver complexes of antibacterial quinolones have the potential advantage of combining the antibacterial activity of silver and fluoroquinolones. The objective of our study was the preparation and the preliminary physico-chemical characterization of a silver complex with ofloxacin.

  4. Preliminary Design Study of a Hybrid Airship for Flight Research

    Science.gov (United States)

    Browning, R. G. E.

    1981-01-01

    The feasibility of using components from four small helicopters and an airship envelope as the basis for a quad-rotor research aircraft was studied. Preliminary investigations included a review of candidate hardware and various combinations of rotor craft/airship configurations. A selected vehicle was analyzed to assess its structural and performance characteristics.

  5. Vertical infraclavicular brachial plexus block in children: a preliminary study.

    NARCIS (Netherlands)

    Jose Maria, B. de; Tielens, L.K.P.

    2004-01-01

    BACKGROUND: Brachial plexus blockade is a well-established technique in upper limb surgery. Among the infraclavicular approaches, the vertical infraclavicular brachial plexus (VIP) block is easy to perform and has a large spectrum of nerve blockade. The aim of this preliminary study was to determine

  6. Preliminary study on chicken feather protein-based wood adhesives

    Science.gov (United States)

    Zehui Jiang; Daochun Qin; Chung-Yun Hse; Monlin Kuo; Zhaohui Luo; Ge Wang; Yan Yu

    2008-01-01

    The objective of this preliminary study was to partially replace phenol in the synthesis of phenol-formaldehyde resin with feather protein. Feather protein–based resins, which contained one part feather protein and two parts phenol, were formulated under the conditions of two feather protein hydrolysis methods (with and without presence of phenol during...

  7. Preliminary study to AP mine neutralisation by EFP impact

    NARCIS (Netherlands)

    Meulman, J.H.

    2004-01-01

    A preliminary study has been conducted into the response of anti-personnel mines at the impact of an Explosively Formed Projectile (EFP). The objective was to obtain a low order reaction (preferably a deflagration) to minimise collateral damage. Further the method should be capable to neutralise min

  8. Preliminary Sensitivity Study of Upper Head Nodalization for LBLOCA in APR-1400

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Dong Gu; Yoo, Seung Hun; Cho, Dae-Hyung [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2015-10-15

    In this study, the key-way bypass was determined to be - 0.3 %. The steady state condition which is the initial condition for LBLOCA was obtained by MARS-KS calculation. Up to now, it was assumed that the temperature of the upper dome in APR-1400 was close to that of the cold leg. However, it was found that the temperature of the upper head/dome might be a little lower than or similar to that of the hot leg through the evaluation of the detailed design data. Since the higher upper head temperature affects blowdown quenching and peak cladding temperature in the reflood phase, the nodalization for upper head should be modified. In this study, the preliminary sensitivity study of original and modified nodalization for LBLOCA was performed, and the effect of upper head nodalization and temperature was evaluated qualitatively. In this study, the preliminary sensitivity study of original and modified nodalization for upper head in APR-1400 was performed, and the effect of upper head nodalization and temperature on LBLOCA PCT was evaluated qualitatively. Through the transient calculation, it was confirmed that the upper head temperature affects the water inventory in the upper head at the early stage of LBLOCA so it does the blowdown quenching and following reflood PCT significantly. The results in this study were caused by very conservative upper head temperature determination.

  9. Preliminary toxicological study of Irganox 1010

    Energy Technology Data Exchange (ETDEWEB)

    Drake, G.A.; London, J.E.; Smith, D.M.; Thomas, R.G.

    1979-10-01

    Acute oral LD/sub 50/30/ values for mice and rats receiving Irganox 1010 were found to be greater than 5 g/kg. According to classical guidelines, this material would be considered slightly toxic or practically nontoxic in both species. Skin applicaton studies in rabbits showed the material to be nonirritating. Eye irritation studies, also in the rabbit, showed that Irganox 1010 was a mild but transitory irritant. The sensitizaton study in guinea pigs did not show the material to be deleterious.

  10. Preliminary toxicological study of Silastic 386 catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Smith, D.M.; Drake, G.A.; Holland, L.M.; Jackson, D.E.; London, J.E.; Prine, J.R.; Thomas, R.G.

    1978-06-01

    The calculated acute oral LD/sub 50//sup 30/ values for Silastic 386 catalyst were 1225 mg/kg in mice and 4350 mg/kg in rats. According to classical guidelines, the compound would be slightly to moderately toxic in both species. Skin application studies in the rabbit demonstrated the compound to be mildly irritating. The eye irritation study disclosed the compound to be a severe irritant causing conjunctivitis, photophobia, corneal edema, corneal ulceration, anterior uveitis, and keratitis. The sensitization study in the guinea pig did not show Silastic 386 catalyst to be deleterious in this regard.

  11. Diesel engine emission deterioration - a preliminary study

    CSIR Research Space (South Africa)

    Pretorius, Cecilia J

    2016-04-01

    Full Text Available The objective of this study was to find a parameter in diesel and oil analysis of underground mining vehicles that can be correlated with personal diesel particulate matter (DPM) exposure and used as part of an engine maintenance programme. A number...

  12. Preliminary study of pur-revetment's application

    NARCIS (Netherlands)

    Gu, D.; Verhagen, H.J.; Van de Ven, M.

    2008-01-01

    PUR-revetment is a newly developed method for hydraulic application. Its structure is similar to that of open stone asphalt revetment, but the crushed stones are glued by polyurethane (PUR) instead of bitumen. To study the feasibility of applying PUR-revetment, a research based on the comparisons be

  13. Caregivers with Visual Impairments: A Preliminary Study

    Science.gov (United States)

    Fuhr, Patti; Martinez, Bethany; Williams, Michael

    2008-01-01

    Persons who are elderly, visually impaired, and primary caregivers for ailing or disabled spouses or significant others are a unique population that has not been studied previously. By definition, "informal caregivers" are family members or friends who provide unpaid day-to-day assistance with activities of daily living and are familiar with the…

  14. Improving the spatial resolution in CZT detectors using charge sharing effect and transient signal analysis: Simulation study

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Xiaoqing; Cheng, Zeng [Department of Electrical and Computer Engineering, McMaster University (Canada); Deen, M. Jamal, E-mail: jamal@mcmaster.ca [Department of Electrical and Computer Engineering, McMaster University (Canada); School of Biomedical Engineering, McMaster University (Canada); Peng, Hao, E-mail: penghao@mcmaster.ca [Department of Electrical and Computer Engineering, McMaster University (Canada); School of Biomedical Engineering, McMaster University (Canada); Department of Medical Physics, McMaster University, Ontario L8S 4K1, Hamilton (Canada)

    2016-02-01

    Cadmium Zinc Telluride (CZT) semiconductor detectors are capable of providing superior energy resolution and three-dimensional position information of gamma ray interactions in a large variety of fields, including nuclear physics, gamma-ray imaging and nuclear medicine. Some dedicated Positron Emission Tomography (PET) systems, for example, for breast cancer detection, require higher contrast recovery and more accurate event location compared with a whole-body PET system. The spatial resolution is currently limited by electrode pitch in CZT detectors. A straightforward approach to increase the spatial resolution is by decreasing the detector electrode pitch, but this leads to higher fabrication cost and a larger number of readout channels. In addition, inter-electrode charge spreading can negate any improvement in spatial resolution. In this work, we studied the feasibility of achieving sub-pitch spatial resolution in CZT detectors using two methods: charge sharing effect and transient signal analysis. We noted that their valid ranges of usage were complementary. The dependences of their corresponding valid ranges on electrode design, depth-of-interaction (DOI), voltage bias and signal triggering threshold were investigated. The implementation of these two methods in both pixelated and cross-strip configuration of CZT detectors were discussed. Our results show that the valid range of charge sharing effect increases as a function of DOI, but decreases with increasing gap width and bias voltage. For a CZT detector of 5 mm thickness, 100 µm gap and biased at 400 V, the valid range of charge sharing effect was found to be about 112.3 µm around the gap center. This result complements the valid range of the transient signal analysis within one electrode pitch. For a signal-to-noise ratio (SNR) of ~17 and preliminary measurements, the sub-pitch spatial resolution is expected to be ~30 µm and ~250 µm for the charge sharing and transient signal analysis methods

  15. Improving the spatial resolution in CZT detectors using charge sharing effect and transient signal analysis: Simulation study

    Science.gov (United States)

    Zheng, Xiaoqing; Cheng, Zeng; Deen, M. Jamal; Peng, Hao

    2016-02-01

    Cadmium Zinc Telluride (CZT) semiconductor detectors are capable of providing superior energy resolution and three-dimensional position information of gamma ray interactions in a large variety of fields, including nuclear physics, gamma-ray imaging and nuclear medicine. Some dedicated Positron Emission Tomography (PET) systems, for example, for breast cancer detection, require higher contrast recovery and more accurate event location compared with a whole-body PET system. The spatial resolution is currently limited by electrode pitch in CZT detectors. A straightforward approach to increase the spatial resolution is by decreasing the detector electrode pitch, but this leads to higher fabrication cost and a larger number of readout channels. In addition, inter-electrode charge spreading can negate any improvement in spatial resolution. In this work, we studied the feasibility of achieving sub-pitch spatial resolution in CZT detectors using two methods: charge sharing effect and transient signal analysis. We noted that their valid ranges of usage were complementary. The dependences of their corresponding valid ranges on electrode design, depth-of-interaction (DOI), voltage bias and signal triggering threshold were investigated. The implementation of these two methods in both pixelated and cross-strip configuration of CZT detectors were discussed. Our results show that the valid range of charge sharing effect increases as a function of DOI, but decreases with increasing gap width and bias voltage. For a CZT detector of 5 mm thickness, 100 μm gap and biased at 400 V, the valid range of charge sharing effect was found to be about 112.3 μm around the gap center. This result complements the valid range of the transient signal analysis within one electrode pitch. For a signal-to-noise ratio (SNR) of ~17 and preliminary measurements, the sub-pitch spatial resolution is expected to be ~30 μm and ~250 μm for the charge sharing and transient signal analysis methods

  16. Preliminary Study of Performance of TTA Resin

    Institute of Scientific and Technical Information of China (English)

    HUANG; Kun; MAO; Guo-shu

    2013-01-01

    TTA(thenoyl trifluoroacetone)extraction can effectively remove large amounts of uranium in the analysis of trace neptunium in the presence of large amounts of uranium.While it is not conducive to achieve the automation of the rapid analysis of neptunium with the TTA solution,the TTA resin was prepared and its properties were studied in this work.TTA resin in this work was a kind of mixture combining styrene-divinylbenzene skeleton with TTA

  17. Microwave Influence in Fungi a Preliminary Study

    Energy Technology Data Exchange (ETDEWEB)

    Manoliu, A. I.; Tufescu, F. M.; Oprica, L.; Olteanu, Z.; Creanga, D. E.

    2004-07-01

    The behavior of two cellulolytic fungus species under the influence of low intensity microwaves was studied: Chaetomium globosum and Alternaria alternata. Enzyme activity of dehydrogenase complex was investigated by spectrophotometric method in order to real the effect of relatively short daily exposure times. Inhibitory effect was noticed for malate dehydrogenase and succinate dehydrogenase in both fungi while differentiated influence was revealed in alpha ceto glutarate dehydrogenase (inhibitory in Chaetomium globosum but stimulatory in Alternaria alternata). Isocitrate dehydrogenase activity was significantly stimulated in both fungi for 3 hours exposure time. (Author) 15 refs.

  18. [Preliminary study on the pharmacological action spicatus].

    Science.gov (United States)

    Gai, H; Shou, Y; Wang, J; Li, L

    1997-01-01

    In this report the pharmacological action of Spicatus was studied. The results insicated that it had diureric, antibiotic and anti-inflammatory effects, yet had Iittle toxic side-effect. It had significant inhibitory effect on crofon oil-caused mice ear swell. It also had marked diuretic effect in orcinary rats, but had Iittie effect on uric pH the rats. It exhibited certain inhibition of Staphycoloccus aureus, Eschrichia coli and Pseudomonas aeruginosa in vitro. The maximum tolerable dose test in mice showed no marked toxic effect, LD50 > 80 g/kg.

  19. A preliminary ultrasound study of velar fronting

    Science.gov (United States)

    Wodzinski, Sylvie M.; Frisch, Stefan A.

    2003-10-01

    The purpose of this study is to (1) evaluate the effectiveness of ultrasound imaging to measure velar consonant closure location, and (2) conduct a thorough study of velar fronting by measuring several productions of velar stops in the context of every English vowel. Word onset velar stops were measured in both words (CV or CVC) and nonwords (VCV) within a carrier phrase. Other coarticulatory influences were minimized by using words with no coda or labial coda consonants (e.g., ``Say a gap again,'' ``Say /oIkoI/ again''). Measurements were made at the point of maximal closure. Closure location was measured using the radial angle from the center of the ultrasound probe to the center of the velar closure. Pilot data for one subject has been analyzed to date. Closure location appears consistent across all central and back vowels. For front vowels, the degree of fronting of the velar appears to be correlated with the frontness of the vowel. Measures of closure location for diphthongs followed the back vowel pattern in the word targets. For nonwords, the closure location was influenced by the preceding diphthong offset quality and the following diphthong onset quality. Theoretical implications for the phonetics/phonology interface will be discussed.

  20. Preliminary study of disc hydrodynamic polishing.

    Science.gov (United States)

    Li, Yan; Lin, Bin; Zhang, XiaoFeng; Liu, PengFei

    2016-10-01

    In this paper, a developed polishing method based on elastic emission machining and Jules Verne-a variation on fluid jet polishing-is presented. This method is named disc hydrodynamic polishing (DHDP). A computational fluid dynamics (CFD)-based model that consists of a CFD model and an erosion model is introduced to predict the surface roughness obtained by DHDP. The performance of DHDP is studied by experiments. The slurry used in the experiments comprises 95% deionized water and 5% cerium oxide particles. Fused-silica glass is chosen as the workpiece. After the experiments, an ultrasmooth surface without cracks is obtained. The simulation results principally coincide with the experimental results. The experimental results show that the actual roughness is slightly less than the prediction and smaller particles are more favorable for obtaining a better surface roughness.

  1. A Preliminary Study of Fake Fingerprints

    Directory of Open Access Journals (Sweden)

    Qinghai Gao

    2014-11-01

    Full Text Available Fingerprint is a widely used biometrics. Its extensive usage motivates imposter to fabricate fake fingerprints. Vitality detection has been proposed to prevent counterfeit finger attack. Currently the detection can be done either during the process of acquiring fingerprint image or by comparing multiple sequentially acquired images. It is an ongoing research problem to detect whether a given fingerprint image is obtained from a real or a fake fingertip. In this paper we look into the differences between real and fake fingerprints as the first step to approach this problem. Specifically, we study the effects of different imaging sensors on the sizes of templates and on the matching scores between real and fake fingerprints. We also compare the fake fingerprints made from different materials. Experiments are carried out with two publicly available fingerprint databases and the findings are reported.

  2. Helicopter pilot back pain: a preliminary study.

    Science.gov (United States)

    Shanahan, D F; Reading, T E

    1984-02-01

    Because of the high prevalence of back pain experienced by U.S. Army helicopter pilots, a study was conducted to ascertain the feasibility of reproducing these symptoms in the laboratory. A mock-up of a UH-1H seat and control configuration was mounted to a multi-axis vibration simulator (MAVS). Eleven subjects were tested on the apparatus for two 120-min periods. During one period, the MAVS was programmed to reproduce vibrations recorded from a UH-1H in cruise flight. The subjects received no vibration during the other test period. All subjects reported back pain which they described as identical to the pain they experience during flight, during one or more of their test periods. There was no statistical difference between the vibration and nonvibration test conditions (p greater than 0.05) in terms of time of onset of pain or intensity of pain as measured by a visual analog scale. It appears the vibration at the frequencies and amplitudes tested plays little or no role in the etiology of the back symptoms reported by these pilots. It is proposed that the primary etiological factor for these symptoms is the poor posture pilots are obliged to assume for extended periods while operating helicopters.

  3. Esophageal clearance scintigraphy in, diabetic patients; A preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Karayalcin, B.; Karayalcin, U.; Aburano, Tamio; Nakajima, Kenichi; Hisada, Kinichi; Morise, Toshio; Okada, Toshihide; Takeda, Ryoyu (Kanazawa Univ. (Japan). School of Medicine)

    1992-05-01

    The aim of this preliminary study was to evaluate the predictive value of esophageal clearance scintigraphy (ECS) in the diagnosis of esophageal autonomic neuropathy in diabetic patients without any esophageal symptoms. A single swallon ECS was performed in 12 diabetic patients and 15 normal volunteers, and esophageal transit time (ETT) and esophageal (Es) T 1/2 values were calculated. ETT and Es 1/2 were found to be significantly prolonged in the diabetic group (p<0.01 and p<0.05, respectively). In this preliminary study, our results strongly suggest that ECS may be an important noninvasive diagnostic tool in the evaluation of diabetic patients with asymptomatic esophageal autonomic neuropathy. (author).

  4. Deproteinated palm kernel cake-derived oligosaccharides: A preliminary study

    Science.gov (United States)

    Fan, Suet Pin; Chia, Chin Hua; Fang, Zhen; Zakaria, Sarani; Chee, Kah Leong

    2014-09-01

    Preliminary study on microwave-assisted hydrolysis of deproteinated palm kernel cake (DPKC) to produce oligosaccharides using succinic acid was performed. Three important factors, i.e., temperature, acid concentration and reaction time, were selected to carry out the hydrolysis processes. Results showed that the highest yield of DPKC-derived oligosaccharides can be obtained at a parameter 170 °C, 0.2 N SA and 20 min of reaction time.

  5. Transient-Grating Study of Electron and Hole Diffusion in (Ga,Mn)As

    Science.gov (United States)

    Kittlaus, Eric

    2011-11-01

    Dilute magnetic semiconductors are a class of materials exhibiting both semiconducting and ferromagnetic properties while being chemically similar to traditional semiconductors. This dual nature presents the opportunity for new ``spintronic'' devices, with the caveat that current dilute magnetic semiconductors are only ferromagnetic above their subzero Curie temperature, Tc. In order to develop new materials functional at room temperature, it is necessary to develop a better theoretical understanding of how such materials become magnetic, a result of microscopic electronic processes. One of the most common dilute magnetic semiconductors, (Ga,Mn)As, is produced by doping Gallium Arsenide with manganese. We use a laser-based experiment, transient-grating spectroscopy, to measure the diffusive motion of electrons and holes in (Ga,Mn)As, which provides information related to the processes which control magnetism in these materials. We present preliminary data and calculations and discuss further improvements in experimental design that will provide unprecedented insight into the microscopic workings of dilute magnetic semiconductors.

  6. Contributions to the Transient Study of an Electric Motor with Shorted Moving Coil

    Directory of Open Access Journals (Sweden)

    Georgescu Daniel

    2014-09-01

    Full Text Available In this article is studied the transient regime of an electric motor with a shorted moving coil, into alternating current supplied. The authors present their contributions related to the conceiving, achieving and testing of experimental stands of an electric motor with a shorted moving coil and to the identification of the mathematical model, indexical function parameters and the coefficients of the mathematical equation of this engine. Finally, the authors' conclusions are presented on the results of experimental studies and moving coil motor behavior in transient regime.

  7. Simplified drive system models for power system transient studies in industrial plants

    DEFF Research Database (Denmark)

    Chen, Peiyuan; Sannino, Ambra

    2007-01-01

    In order to simulate industrial plants for different power system transient studies, simplified adjustable speed drive (ASD) models are needed. For power system transient studies such as assessing the voltage dip ride-through capability of ASDs, detailed representation of semiconductor valve...... switching can be avoided, thereby making possible to increase the time step of the simulation. In this paper, simplified ASD models are developed and compared with corresponding detailed models. The performance of the simplified models is assessed when increasing the simulation step as much as possible...... while still maintaining the error within acceptable limits....

  8. Breakdown transient study of plasma distributions in a 2.45 GHz hydrogen discharge

    Energy Technology Data Exchange (ETDEWEB)

    Cortázar, O.D., E-mail: daniel.cortazar@uclm.es [Universidad de Castilla-La Mancha, ETSII-INEI, Applied Mechanics and Projects Department, C.J. Cela s/n, 13170 Ciudad Real (Spain); Megía-Macías, A. [ESS Bilbao Consortium, Polígono Ugaldeguren-III Pol. A 7B, 48170-Zamudio, Vizcaya (Spain); Tarvainen, O.; Koivisto, H. [University of Jyväskylä, Department of Physics, PO Box 35 (YFL), 40500 Jyväskylä (Finland)

    2015-05-01

    Plasma distribution transients associated with the breakdown of a 2.45 GHz hydrogen discharge similar to high current microwave ion sources are studied by means of an ultra-fast frame image acquisition system in visible light range. Eight different plasma distributions have been studied by photographing the 2D projections of the discharge through a transparent plasma electrode. The temporal evolution of images in Balmer-alpha and Fulcher band wavelengths have been recorded associated to atomic and molecular excitation and ionization processes. Some unexpected plasma distributions transient behaviors during breakdown are reported.

  9. Value of diffusion-weighted imaging after transient taste stimulation in evaluation of salivary gland function before and after radiotherapy:a preliminary study%应用短暂味觉刺激后DWI评价放疗前后涎腺功能的初步研究

    Institute of Scientific and Technical Information of China (English)

    徐亮; 田野; 徐莹莹; 钱建军; 朱雅群; 范秋虹; 张力元; 赵丹蕾; 沈钧康

    2016-01-01

    目的 探讨短暂味觉刺激后DWI评价鼻咽癌患者放疗前后主涎腺功能改变的价值,分析ADC值与其他评价方法间的相关性.方法 2010-2014年对30例鼻咽癌患者在放疗前后行味觉刺激后动态DWI检查,分析各涎腺ADC值变化曲线特点.配对t检验放疗前后ADC峰值时间、静息ADC值、刺激后最大ADC值、最大ADC增加率差异.Pearson分析各涎腺ADC值与唾液流率、放疗后各涎腺ADC值与CTCAE分级和可视模拟分级法评分的相关性.结果 放疗前后各涎腺的ADC值均于味觉刺激后第1次扫描(30 s)达峰值.放疗后各涎腺静息ADC值、刺激后最大ADC值均显著高于放疗前(P值分别为0.000、0.000、0.000和0.001、0.000、0.000).放疗前后各涎腺刺激后最大ADC值增加率差异无统计学意义(P值分别为0.213、0.122、0.839).放疗前颌下腺静息ADC值与全腺体唾液流率间有相关性(r=0.364,P=0.048).结论 短暂味觉刺激后DWI可以有效显示鼻咽癌放疗后各涎腺ADC值动态变化特点及与放疗前差异,在评价涎腺功能减退及动态监测涎腺功能变化方面具有很大潜力.%Objective To investigate the value of diffusion-weighted imaging (DWI) after transient taste stimulation in evaluating salivary gland function before and after radiotherapy (RT),as well as the correlation between apparent diffusion coefficient (ADC) and other evaluation methods.Methods A total of 30 patients with nasopharyngeal carcinoma (NPC) underwent dynamic DWI after taste stimulation before and after RT from 2010 to 2014.The characteristics of ADC changing curves for each salivary gland were analyzed.The paired t-test was used for comparison of the time to ADC peak,resting ADC,maximum ADC after stimulation,and maximum ADC increase rate.Pearson correlation analysis was used to investigate the correlation between ADC of the salivary gland and salivary flow rate,as well as the correlation of ADC of the salivary gland after RT with Common

  10. Experimental study of the pressure fluctuations on propeller turbine runner blades: part 2, transient conditions

    Science.gov (United States)

    Houde, S.; Fraser, R.; Ciocan, G.; Deschênes, C.

    2012-11-01

    Transient conditions such as load rejection will often lead to high amplitude pressure fluctuations that will affect a turbine residual-life. If Computational Fluid Dynamic offers a promising tool to study the flow dynamic under transient regime, focused validation data on the runner are still lacking to assess the accuracy of different simulation strategies. Hence within the framework of the AxialT project of the International Consortium on Hydraulic Machines, exploratory measurements of the pressure field on the runner blades of a propeller turbine model were performed in transient conditions. The model was setup on the test stand of the LAMH of Laval University. The test stand control procedures were adapted to mimic transient condition such as load rejection or the transition from a normal operating condition to a speed-no-load condition. The pressure on the runner blades were measured using miniature piezo-resistive transducer linked to a high frequency telemetric system. Using specifically adapted data processing routines, it was possible to characterize the variations of the energy content during the transient runs. Specifically, the main fluctuations appear to occur in the sub-synchronous range in both cases.

  11. Tree STEM Reconstruction Using Vertical Fisheye Images: a Preliminary Study

    Science.gov (United States)

    Berveglieri, A.; Tommaselli, A. M. G.

    2016-06-01

    A preliminary study was conducted to assess a tree stem reconstruction technique with panoramic images taken with fisheye lenses. The concept is similar to the Structure from Motion (SfM) technique, but the acquisition and data preparation rely on fisheye cameras to generate a vertical image sequence with height variations of the camera station. Each vertical image is rectified to four vertical planes, producing horizontal lateral views. The stems in the lateral view are rectified to the same scale in the image sequence to facilitate image matching. Using bundle adjustment, the stems are reconstructed, enabling later measurement and extraction of several attributes. The 3D reconstruction was performed with the proposed technique and compared with SfM. The preliminary results showed that the stems were correctly reconstructed by using the lateral virtual images generated from the vertical fisheye images and with the advantage of using fewer images and taken from one single station.

  12. TREE STEM RECONSTRUCTION USING VERTICAL FISHEYE IMAGES: A PRELIMINARY STUDY

    Directory of Open Access Journals (Sweden)

    A. Berveglieri

    2016-06-01

    Full Text Available A preliminary study was conducted to assess a tree stem reconstruction technique with panoramic images taken with fisheye lenses. The concept is similar to the Structure from Motion (SfM technique, but the acquisition and data preparation rely on fisheye cameras to generate a vertical image sequence with height variations of the camera station. Each vertical image is rectified to four vertical planes, producing horizontal lateral views. The stems in the lateral view are rectified to the same scale in the image sequence to facilitate image matching. Using bundle adjustment, the stems are reconstructed, enabling later measurement and extraction of several attributes. The 3D reconstruction was performed with the proposed technique and compared with SfM. The preliminary results showed that the stems were correctly reconstructed by using the lateral virtual images generated from the vertical fisheye images and with the advantage of using fewer images and taken from one single station.

  13. Independent power producer parallel operation modeling in transient network simulations for interconnected distributed generation studies

    Energy Technology Data Exchange (ETDEWEB)

    Moura, Fabricio A.M.; Camacho, Jose R. [Universidade Federal de Uberlandia, School of Electrical Engineering, Rural Electricity and Alternative Sources Lab, PO Box 593, 38400.902 Uberlandia, MG (Brazil); Chaves, Marcelo L.R.; Guimaraes, Geraldo C. [Universidade Federal de Uberlandia, School of Electrical Engineering, Power Systems Dynamics Group, PO Box: 593, 38400.902 Uberlandia, MG (Brazil)

    2010-02-15

    The main task in this paper is to present a performance analysis of a distribution network in the presence of an independent power producer (IP) synchronous generator with its speed governor and voltage regulator modeled using TACS -Transient Analysis of Control Systems, for distributed generation studies. Regulators were implemented through their transfer functions in the S domain. However, since ATP-EMTP (Electromagnetic Transient Program) works in the time domain, a discretization is necessary to return the TACS output to time domain. It must be highlighted that this generator is driven by a steam turbine, and the whole system with regulators and the equivalent of the power authority system at the common coupling point (CCP) are modeled in the ''ATP-EMTP -Alternative Transients Program''. (author)

  14. Transient optical gratings for pulsed ionizing radiation studies

    CERN Document Server

    Fullagar, Wilfred K; Hall, Chris J

    2011-01-01

    Prior to the invention of holography or lasers, Bragg's X-ray microscope opened the door to optical computation in short-wavelength studies using spatially coherent visible light, including phase retrieval methods. This optical approach lost ground to semiconductor detection and digital computing in the 1960s. Since then, visible optics including spatial light modulators (SLMs), array detectors and femtosecond lasers have become widely available, routinely allowing versatile and computer-interfaced imposition of optical phase, molecular coherent control, and detection. Today, high brilliance X-ray sources begin to offer opportunities for atomic resolution and ultrafast pump-probe studies. Correspondingly, this work considers an overlooked aspect of Bragg's X-ray microscope - the incoherent ionizing radiation to coherent visible (IICV) conversion that is a necessary prerequisite for coherent optical computations. Technologies are suggested that can accomplish this conversion. Approaches to holographic data sto...

  15. Transient Crossed Aphasia: A Case Study with SPECT

    Directory of Open Access Journals (Sweden)

    José M. Ferro

    1991-01-01

    Full Text Available A 45-year-old right-handed man developed “crossed” anomie aphasia, neglect and inaccurate reaching of his left arm in both hemispaces due to a right parietal haemorrhage. Aphasia cleared in a few days. SPECT failed to demonstrate crossed left hemispheric diaschisis. This report emphasizes the importance of evaluating patients in the acute stage and of coupling “static” and “functional” imaging methods when studying brain-behavior relationships.

  16. Transient cortical blindness: a benign but devastating complication after coronary angiography and graft study.

    Science.gov (United States)

    Sridhar, Ganiga Srinivasaiah; Sadiq, Muhammad Athar; Wan Ahmad, Wan Azman; Supuramaniam, Chitra; Undok, Abdul Wahab; Abidin, Imran Zainal; Chee, Kok Han

    2014-10-01

    Transient cortical blindness after coronary angiography and bypass graft is a very rare complication. In this report we present the case of a 63-year-old man who developed transient cortical blindness within 30 minutes of coronary angioplasty and graft study, but subsequently recovered within 72 hours without any neurological deficit. A plain computed tomography brain scan showed bilateral symmetrical subarachnoid hyperdensities in the posterior cerebral circulation area suspicious of subarachnoid bleed. However, magnetic resonance imaging and magnetic resonance angiography scans were normal. Excess contrast volume causing direct neurotoxicity seems to be the most probable cause, but the exact mechanism is unclear.

  17. Experimental and Numerical Study on Transient Behavior of Printed Circuit Heat

    Energy Technology Data Exchange (ETDEWEB)

    Park, Byung Ha; Kim, Chan Soo [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    A PCHE(printed circuit heat exchanger (PCHE) is manufactured from diffusion bonding process with multiple metal plates, which have plenty of micro channels. Micro channels on the plates were produced by mechanical machining or chemical etching. A PCHE is a very compact type and it has fine operating efficiency and effectiveness, which saves capital cost. PMR coolant is helium. The evaluation method for steady-state thermal hydraulic performance of a PCHE with helium was well developed. Kim performed a transient test. Cold inlet temperature was suddenly decreased after steady-state. Decreased temperature was about 20. The studies of transient response for counter flow configuration using both analytical and numerical method were well reviewed by Bunce and Kandiakr. Many authors considered conventional heat exchangers, such as shell and tube type. They considered interfacing wall between two fluids but outer shell of heat exchanger was not considered for transient behavior. However, heavy top cover plate and bottom cover plate are attached by diffusion bonding to endure high pressure from working fluid in PCHE. The mass of metal is very large. It is believed that a PCHE system has slow response time because of the heavy metal plates. It is needed to consider the effect of cover plate to evaluate transient behavior of PCHE. The transient behavior of PCHE was experimentally and numerically analyzed in the present study. A PCHE modeling should be performed with considerations on total PCHE metal mass and total heat transfer area. A PCHE has relatively large volume of metal compared with fluid channel due to cover plates to endure high pressure condition. The transient behavior is very sensitive to the metal mass in PCHE. The presented experimental results show start-up process for high temperature operation. Careful consideration is required to design a PCHE system with helium coolant.

  18. Online gaming dependency: a preliminary study in China.

    Science.gov (United States)

    Peng, Wei; Liu, Ming

    2010-06-01

    Based on theories and previous studies on problematic Internet use, we propose a model to better understand the contributors to and consequences of online gaming dependency. A preliminary study was conducted through a survey of online gamers in China. The results of path analysis found that maladaptive cognitions, shyness, and depression are positively related to online gaming dependency. Online gaming dependency was also positively related to different types of negative life outcomes. The findings of this study have implications for the prevention and treatment of addictive online gaming.

  19. Study of transient current induced by heavy-ion microbeams in Si and GaAs

    Energy Technology Data Exchange (ETDEWEB)

    Hirao, Toshio; Nashiyama, Isamu; Kamiya, Tomihiro; Suda, Tamotu [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    1997-03-01

    Heavy-ion microbeams were applied to the study of mechanism of single event upset (SEU). Transient current induced in p{sup +}n junction diodes by strike of heavy ion microbeam were measured by using a high-speed digitizing sampling system. (author)

  20. Modeling and Testing of EVs - Preliminary Study and Laboratory Development

    DEFF Research Database (Denmark)

    Yang, Guang-Ya; Marra, Francesco; Nielsen, Arne Hejde

    2010-01-01

    impact at different geographical areas, as well as driving and charging patterns. Electric circuit model is deployed in this work to represent the electrical properties of a lithium-ion battery. This paper reports the preliminary modeling and validation work based on manufacturer data sheet and realistic......Electric vehicles (EVs) are expected to play a key role in the future energy management system to stabilize both supply and consumption with the presence of high penetration of renewable generation. A reasonably accurate model of battery is a key element for the study of EVs behavior and the grid...... tests, followed by the suggestions towards a feasible battery model for further studies....

  1. Photodynamic therapy of port wine stain: preliminary clinical studies

    Science.gov (United States)

    Nelson, J. Stuart

    1993-07-01

    The broad, long term objective of this work is the development of Photodynamic Therapy (PDT) for application in the clinical management of patients with port wine stain (PWS). PDT involves the use of an exogenous drug which is concentrated in a targeted tissue. When irradiated at wavelengths specifically absorbed by the drug, selective destruction of the targeted tissue, without the production of heat, occurs. The results of this preliminary study demonstrate in human PWS patients that a photosensitizer, such as PHOTOFRINR, activated by red light at the appropriate therapeutic wavelength, can cause destruction of subsurface blood vessels in the skin with a high degree of specificity, and further study appears warranted.

  2. Preliminary study of the decay heat removal strategy for the gas demonstrator allegro

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, Gusztáv, E-mail: gusztav.mayer@energia.mta.hu [Hungarian Academy of Sciences, Centre for Energy Research, P.O. Box 49, H-1525 Budapest (Hungary); Bentivoglio, Fabrice, E-mail: fabrice.bentivoglio@cea.fr [CEA/DEN/DM2S/STMF/LMES, F-38054, Grenoble (France)

    2015-05-15

    Highlights: • Improved decay heat removal strategy was adapted for the 75 MW ALLEGRO MOX core. • New nitrogen injection strategy was proposed for the DEC LOCA transients. • Preliminary CATHARE study shows that most of the investigated transients fulfill criteria. • Further improvements and optimizations are needed for nitrogen injection. - Abstract: The helium cooled Gas Fast Reactor (GFR) is one of the six reactor concepts selected in the frame of the Generation IV International Forum. Since no gas cooled fast reactor has ever been built, a medium power demonstrator reactor – named ALLEGRO – is necessary on the road towards the 2400 MWth GFR power reactor. The French Commissariat à l’Energie Atomique (CEA) completed a wide range of studies during the early stage of development of ALLEGRO, and later the ALLEGRO reactor concept was developed in several European Union projects in parallel with the GFR2400. The 75 MW thermal power ALLEGRO is currently developed in the frame of the European ALLIANCE project. As a result of the collaboration between CEA and the Hungarian Academy of Sciences Centre for Energy Research (MTA EK) new improvements were done in the safety approach of ALLEGRO. A complete Decay Heat Removal (DHR) strategy was devised, relying on the primary circuits as a first way to remove decay heat using pony-motors to drive the primary blowers, and on the secondary and tertiary circuits being able to work in forced or natural circulation. Three identical dedicated loops circulating in forced convection are used as a second way to remove decay heat, and these loops can circulate in natural convection for pressurized transients, providing a third way to remove decay heat in case of accidents when the primary circuit is still under pressure. The possibility to use nitrogen to enhance both forced and natural circulation is discussed. This DHR strategy is supported by a wide range of accident transient simulations performed using the CATHARE2 code

  3. Study on boundary conditions considering unwinding velocity in transient unwinding equations of motion

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Jin Seok; Yoo, Wan Suk [Pusan National University, Busan (Korea, Republic of); Kim, Kun Woo; Lee, Jae Wook [Korea Institute of Industrial Technology, Daegu (Korea, Republic of)

    2015-07-15

    The unwinding behavior of thin cable has been studied in textile engineering. Recently, J.W. Lee derived transient equations of motion for an unwinding cable. Thus, this paper discusses numerical simulations of unwinding behavior as compared to experiments. The cable unwinding system is modeled using cylindrical coordinates, and Hamilton's principle in an open system is used to represent the mass change of the cable in the control volume. In a transient equation of unwinding motion, the transient-state response is affected by two point boundary conditions, such as the guide-eyelet point and the lift-off point. In previous research, only the unwinding velocity at the guide-eyelet point defined the boundary. Here, a boundary condition at the lift-off point is also considered in the unwinding velocity along with the unwinding length of cable in the control volume. The results of this study show that transient equations of motion should be derived by considering angular acceleration because of time-varying angular velocity.

  4. Preliminary study on rockfall for Al Gayah site in Yemen

    Institute of Scientific and Technical Information of China (English)

    Aref M. O. Al-Jabali; WANG Xi-kui

    2004-01-01

    Studying the landslide and rockfall in Yemen still in its preliminary stage. Al Gayah rockfall site is a chronic problem as many other areas in the Republic of Yemen. The present authors have tried to highlight, and find best solution for this problem for the first time. Field work, collecting data and laboratory test for many rock samples such physical properties, chemical for major elements and thin section have been carried out. The physical properties performed according to ASTM, and then the result have been gotten and discussed.

  5. MOLECULAR IDENTIFICATION AND GENOTYPING OF CIAUSCOLO AUTOCHTHONOUS MICROFLORA: PRELIMINARY STUDY

    Directory of Open Access Journals (Sweden)

    A. Petruzzelli

    2011-01-01

    Full Text Available The present study reports the results of a preliminary characterization of the bacterial population of Ciauscolo, a typical Italian fermented sausage, traditionally manufactured in Marche region. The bacterial community involved in Ciauscolo fermentation was investigated using both molecular and culturebased methods. The estimation of genotypic intra-species variation of the autochthonous bacteria isolated was also evaluated by using randomly amplified polymorphic DNA (RAPD analysis and unweighted pairgroup method with arithmetic averages (UPGMA cluster analysis. Our findings revealed an high diversity of the autochthonous bacterial population investigated, both at species and strain level.

  6. Preliminary Studies on Chlorimuron Degradation in Soil by Effective Microogranisms

    Institute of Scientific and Technical Information of China (English)

    LIU Yaguang

    2006-01-01

    A wheat (Triticum aestivum L.) bioassay method was used for preliminary determination of chlorimuron degradation in soil by EM (effective microorganisms). Under the conditions of this study, chlorimuron half-life was greater than 30-50 days in soil containing different initial concentrations of chlorimuron. After adding EM, chlorimuron degradation half-life ranged from 10-15 days, which was about 15-30 days shorter than without EM. Chlorimuron phate and urea enhanced the ability of EM to degrade chlorimuron, but brown sugar had no significant effect.

  7. Corporate Social Disclosures in Southeast Asia: A Preliminary Study

    Directory of Open Access Journals (Sweden)

    Juniati Gunawan

    2012-12-01

    Full Text Available The issue of Corporate Social Disclosure (CSD has been growing remarkably both in business and academic world.  Inevitably, this topic is also exposed in Southeast Asia, a big region that plays important role in global economic issue. Applying a content analysis method, this paper aims to provide preliminary findings in CSD practices throughout the companies‟ annual reports in 2007 and 2008 for countries located in Southeast Asia.  Samples were selected for listed and unlisted various type of industries, based on the information availability internet searching. The sample collection and the subjectivity during the content analysis process are the limitations in conducting this study. In general, the results show that „human resources‟ are the main information disclosed, while in contrast, „energy‟ is the main least issue disclosed in the annual reports.  However, the findings need to be interpreted with considerations since there are limited in samples. Basically, the outcomes support the major prior studies and enhancing the discussion of CSD conducting in developing countries, while at the same time describing some countries which obtained very limited in exposures. To respond the vast increasing issues of CSD practice, this preliminary study has provided a basis to see the role of every country in CSR reporting and how they could support the sustainability development globally.

  8. The complex of SAO RAS optical instruments as an instrument for studying transient sources in the Universe

    Science.gov (United States)

    Vlasyuk, V. V.; Sokolov, V. V.

    2016-06-01

    The paper describes the optical telescopes of SAO RAS and available equipment suitable for studying transient sources. The first experience of investigation of one of the fist gamma-ray bursts (GRB 970508) dates back to 1997. The experience accumulated since then in studying transient sources is also described. Future prospects are outlined.

  9. Preliminary design study of the TMT Telescope structure system: overview

    Science.gov (United States)

    Usuda, Tomonori; Ezaki, Yutaka; Kawaguchi, Noboru; Nagae, Kazuhiro; Kato, Atsushi; Takaki, Junji; Hirano, Masaki; Hattori, Tomoya; Tabata, Masaki; Horiuchi, Yasushi; Saruta, Yusuke; Sofuku, Satoru; Itoh, Noboru; Oshima, Takeharu; Takanezawa, Takashi; Endo, Makoto; Inatani, Junji; Iye, Masanori; Sadjadpour, Amir; Sirota, Mark; Roberts, Scott; Stepp, Larry

    2014-07-01

    We present an overview of the preliminary design of the Telescope Structure System (STR) of Thirty Meter Telescope (TMT). NAOJ was given responsibility for the TMT STR in early 2012 and engaged Mitsubishi Electric Corporation (MELCO) to take over the preliminary design work. MELCO performed a comprehensive preliminary design study in 2012 and 2013 and the design successfully passed its Preliminary Design Review (PDR) in November 2013 and April 2014. Design optimizations were pursued to better meet the design requirements and improvements were made in the designs of many of the telescope subsystems as follows: 1. 6-legged Top End configuration to support secondary mirror (M2) in order to reduce deformation of the Top End and to keep the same 4% blockage of the full aperture as the previous STR design. 2. "Double Lower Tube" of the elevation (EL) structure to reduce the required stroke of the primary mirror (M1) actuators to compensate the primary mirror cell (M1 Cell) deformation caused during the EL angle change in accordance with the requirements. 3. M1 Segment Handling System (SHS) to be able to make removing and installing 10 Mirror Segment Assemblies per day safely and with ease over M1 area where access of personnel is extremely difficult. This requires semi-automatic sequence operation and a robotic Segment Lifting Fixture (SLF) designed based on the Compliance Control System, developed for controlling industrial robots, with a mechanism to enable precise control within the six degrees of freedom of position control. 4. CO2 snow cleaning system to clean M1 every few weeks that is similar to the mechanical system that has been used at Subaru Telescope. 5. Seismic isolation and restraint systems with respect to safety; the maximum acceleration allowed for M1, M2, tertiary mirror (M3), LGSF, and science instruments in 1,000 year return period earthquakes are defined in the requirements. The Seismic requirements apply to any EL angle, regardless of the

  10. Schlieren Studies of Compressibility Effects on Dynamic Stall of Airfoils in Transient Pitching Motion

    OpenAIRE

    Chandrasekhara, M.S.; Ahmed, S; Carr, L.W.

    1990-01-01

    Compressibility effects on the flowfield of an airfoil executing rapid transient pitching motion from 0 - 60 degrees over a wide range of Mach numbers and pitching rates were studied using a stroboscopic schlieren flow visualization technique. The studies have led to the first direct experiments] documentation of multiple shocks on the airfoil upper surface flow for certain conditions. Also, at low Mach numbers, additional coherent vortical structures were found to be ...

  11. Schlieren Studies of Compressibility Effects on Dynamic Stall on Transiently Pitching Airfoils

    OpenAIRE

    Chandrasekhara, M.S.; Ahmed, S; Carr, L.W.

    2016-01-01

    The article of record as published may be found at http://dx.doi.org/10.2514/3.48268 Compressibility effects on the flowfield of an airfoil executing rapid transient pitching motion from 0-60 deg over a wide range of Mach numbers and pitching rates were studied using a stroboscopic schlieren flow visualization technique. The studies have led to the first direct experimental documentation of multiple shocks on the airfoil upper surface flow for certain conditions. Also, at low Mach...

  12. Nevada potential repository preliminary transportation strategy Study 2. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-02-01

    The objectives of this study were to build on the findings of the Nevada Potential Repository Preliminary Transportation Strategy Study 1 (CRWMS M&O 1995b), and to provide additional information for input to the repository environmental impact statement (EIS) process. In addition, this study supported the future selection of a preferred rail corridor and/or heavy haul route based on defensible data, methods, and analyses. Study research did not consider proposed legislation. Planning was conducted according to the Civilian Radioactive Waste Management Program Plan (DOE 1994a). The specific objectives of Study 2 were to: eliminate or reduce data gaps, inconsistencies, and uncertainties, and strengthen the analysis performed in Study 1; develop a preliminary list of rail route evaluation criteria that could be used to solicit input from stakeholders during scoping meetings. The evaluation criteria will be revised based on comments received during scoping; restrict and refine the width of the four rail corridors identified in Study 1 to five miles or less, based on land use constraints and engineering criteria identified and established in Study 2; evaluate national-level effects of routing spent nuclear fuel and high-level waste to the four identified branch lines, including the effects of routing through or avoiding Las Vegas; continue to gather published land use information and environmental data to support the repository EIS; continue to evaluate heavy haul truck transport over three existing routes as an alternative to rail and provide sufficient information to support the repository EIS process; and evaluate secondary uses for rail (passenger use, repository construction, shared use).

  13. R&D Requirements, RF Gun Mode Studies, FEL-2 Steady-StateStudies, Preliminary FEL-1 Time-Dependent Studies, and Preliminary LayoutOption Investigation

    Energy Technology Data Exchange (ETDEWEB)

    Byrd, John; Corlett, John; Doolittle, Larry; Fawley, William; Lidia, Steven; Penn, Gregory; Ratti, Alex; Staples, John; Wilcox Russell; Wurtele, Jonathan; Zholents, Alexander

    2005-10-01

    This report constitutes the third deliverable of LBNLs contracted role in the FERMI {at} Elettra Technical Optimization study. It describes proposed R&D activities for the baseline design of the Technical Optimization Study, initial studies of the RF gun mode-coupling and potential effects on beam dynamics, steady-state studies of FEL-2 performance to 10 nm, preliminary studies of time-dependent FEL-1 performance using electron bunch distribution from the start-to-end studies, and a preliminary investigation of a configuration with FEL sinclined at a small angle from the line of the linac.

  14. [Laparoscopic inguinal hernia repair "IPOM" vs "open tension free". Preliminary results of a prospective randomized study].

    Science.gov (United States)

    Catani, M; De Milito, R; Spaziani, E; Chiaretti, M; Manili, G; Capitano, S; Di Filippo, A; Simi, M

    2003-12-01

    The authors report the preliminary results of a prospective comparison of IPOM (group A) and "open tension free" (group B) hernioplasty in 50 patients having a mono or bilateral primitive hernia. In group A (26 patients) hernia repair was performed using "Gore-Tex DualMesh Plus biomaterial with holes Corduroy" and in group B (24 patients) using the patch and plug technique with Marlex prosthesis. No intraoperative complications occurred and, in group A, no conversion was necessary. Four minor complications were obser-ved in group A (10.8%): 3 seromas and 1 transient paresthesia; 5 in group B (16%): 4 hematomas and 1 wound infection (p=n.s.). In group A only 2 patients (7.6%) needed analgesics after the first 24 hours and 12 patients (50%) in group B (p<0.001). Mean resumption of normal activity was 8 days in group A and 17 days in group B (p<0.001). At a 12-month-follow-up, no recurrence was reported in both groups. The results of this prospective randomized study show that IPOM may be not only a feasible and effective procedure in the treatment of recurrent and bilateral hernia or when hernia repair is performed during other laparoscopic procedures, but also in particular cases of primitive hernia such as in very active young males or heavy duty workers. However it is necessary to definitely ascertain the true incidence of recurrence in non limited series and in longer follow-up and the preliminary results of this study encourage the authors to complete the randomized study.

  15. Results of preliminary Microwave Multi-Applications Payload (MMAP) study

    Science.gov (United States)

    1975-01-01

    A preliminary feasibility study of the microwave multi-applications payload (MMAP) system for the Spacelab has been carried out. The initial objectives of this study have been to determine the minimum equipment requirements of the MMAP and the feasibility of placing the numerous large aperture antennas in the Spacelab. The study was begun by reviewing the experimental objectives and techniques and determining areas of commonality. Emphasis was given to the determination of common RF equipment requirements. These requirementers were considered after agreement among the experiments had been reached on limiting the number of frequencies to be used in the system. This was done so that the number of antennas, transmitters, and receivers could be minimized. The electronics system block diagram and the antenna configurations were considered in some details. It was concluded that the MMAP is feasible and can be an economical method of achieving a large number of experimental goals.

  16. A PRELIMINARY STUDY OF STEREOSELECTIVITY OF MEFLOQUINE ENANTIOMERS IN RAT

    Directory of Open Access Journals (Sweden)

    E. Souri.

    1998-08-01

    Full Text Available Stereoselectivity of mefloquine enantiomers were studied in rats after oral administration of a single 50mg/Kg dose of the racemate. Pharmacokinetic parameters of (+-(RS-MFQ in blood and plasma showed no significant difference. The concentration, AUC , CLIF and VdlF of (+-(RS-enantiomerin blood were significantly higher than those for the (--(SR-enantiomer. Tlie results obtained from this study showed a reverse stereoselectivity of MFQ as compared with what reported for human. A very low amount of enantiomers excreted in urine and the excretion was not stereoselective. A preliminary study in different blood fractions showed that the accumulation of MFQ enantiomers in blood cells is stereoselective with a tendency of ( + -(RS-enatiomer for leukocytes and (--(SR-enantiomer for erythrocytes.

  17. Computer simulation and experimental study of transient processes in a single-phase voltage transformer

    Science.gov (United States)

    Kruzhaev, A. V.; Elagin, I. A.; Pavleino, M. A.; Dmitriev, V. A.; Chaly, A. M.

    2015-02-01

    We perform simulation and experimental investigation of transient processes emerging in a single-phase transformer when it is connected to the network. The transformer model constructed taking into account the saturation of the steel of the core differs from standard models in detailed accounting for the magnetic flux leakage, which is required, for example, for a correct description of inrush current. Universality of the model for the type of transformers under study is ensured by the allowance for eddy current losses and calculation of the magnetic hysteresis in the steel core. The latter makes it possible to estimate the effect of residual magnetization of the core on the form of a transient process, which is studied in detail. The methods for computing model parameters are described and its experimental verification is carried out.

  18. A Comparison Study of the Eigenvalue Method for the Solution of the Transient Heat Conduction Equation.

    Science.gov (United States)

    1986-01-01

    1966). 3. Canale, R.P. and S.C. Chapra . Numerical Methods for Engineers with Personnel Computer Applications. New York: McGraw-Hill 509-533, ( 1985...This study looks at numerical % methods from an engineer’s view, a tool to be used in solving problems. This paper has given me much needed experience... numerical method in solving the transient heat conduction equation. The eigenvalue method was compared to five other numerical methods : Runge-Kutta

  19. Gelation in free-radical crosslinking copolymerization; fast transient fluorescence study

    OpenAIRE

    Ö. Pekcan; D. Kaya

    2002-01-01

    The fast transient fluorescence (FTRF) technique was used to study the sol-gel phase transition in free-radical crosslinking copolymerization (FCC) in two different monomeric systems. Pyrene (Py) was used as a fluorescence probe for the in situ polymerization experiments. The fluorescence lifetimes of Py from its decay traces were measured and used to monitor the gelation process. Monomer consumption profiles were determined during gelation process using Stern-Volmer model. Gelations...

  20. Preliminary Studies for Three Experiments at Treiman-Yang Criterion

    Science.gov (United States)

    Kres, I. V.; Kondratyev, V. N.; Cherubini, S.; Spitaleri, C.

    2016-05-01

    Nuclear reactions with three bodies in their final state may proceed through different reaction mechanisms. The Feynman graph technique has been widely used to describe such reactions. However, it is very difficult in general to select the graphs that dominate in given process. The Treiman-Yang criterion is one of the most powerful experimental tests for verifying the pole approximation prediction when describing a quasi-free reaction mechanism. We propose the theoretical study of the H2(B10, α Be7)ns, H1(B11, α1α2)αs, He3(Be9, α1α2)αs reactions at different energies. The preliminary study helps to check the existence of a QF channel by using the TY creterion.

  1. Recurrent laryngeal nerve histopathology in spastic dysphonia: a preliminary study.

    Science.gov (United States)

    Dedo, H H; Izdebski, K; Townsend, J J

    1977-01-01

    Spastic dysphonia is a severe voice disorder ordinarily described as psychogenic. Organic-neurologic changes secondary to central or peripheral nervous system involvement have also been postulated and led recently to the surgical treatment of spastic dysphonia by unilateral section of the recurrent laryngeal nerve (RLN). This study reports the histologic findings from these resections of the RLN from patients with an average 9.5 years duration of spastic dysphonia. Thirty percent of the RLNs examined demonstrated significant abnormalities as compared to age-matched controls. Although no reactive changes were noted by light microscopy, groups of fibers which did not stain for myelin or axons were found in RLNs from patients with spastic dysphonia. A preliminary ultrastructural study of these areas in one RLN revealed sheets of unmyelinated axons. These findings suggest an organic basis for spastic dysphonia at least in some patients.

  2. First Breath prenatal smoking cessation pilot study: preliminary findings.

    Science.gov (United States)

    Jehn, Lisette; Lokker, Nicole; Matitz, Debra; Christiansen, Bruce

    2003-01-01

    Despite the many dangers associated with smoking during pregnancy, it remains a salient public health problem for Wisconsin women. The First Breath pilot program was developed in an attempt to reduce rates of smoking during pregnancy among low-income women. Preliminary results suggest that the First Breath counseling-based approach is effective, with a quit rate of 43.8% among First Breath enrollees at 1 month postpartum. Women receiving First Breath cessation counseling also had higher quit rates at every measurement period versus women in a comparison group who were receiving whatever cessation care was available in their county in the absence of First Breath. The First Breath pilot study has demonstrated success in helping pregnant women quit smoking and in creating a model for integration of cessation services into prenatal health care service provision. It is through this success that First Breath is expanding beyond the pilot study stage to a statewide program in 2003.

  3. Excited-state dynamics of a ruthenium(II) catalyst studied by transient photofragmentation in gas phase and transient absorption in solution

    Energy Technology Data Exchange (ETDEWEB)

    Imanbaew, D.; Nosenko, Y. [Fachbereich Chemie, Technische Universität Kaiserslautern, Erwin-Schrödinger-Str. 52–54, 67663 Kaiserslautern (Germany); Forschungszentrum OPTIMAS, Erwin-Schrödinger-Str. 46, 67663 Kaiserslautern (Germany); Kerner, C. [Fachbereich Chemie, Technische Universität Kaiserslautern, Erwin-Schrödinger-Str. 52–54, 67663 Kaiserslautern (Germany); Chevalier, K.; Rupp, F. [Fachbereich Physik, Technische Universität Kaiserslautern, Erwin-Schrödinger-Str. 46, 67663 Kaiserslautern (Germany); Riehn, C., E-mail: riehn@chemie.uni-kl.de [Fachbereich Chemie, Technische Universität Kaiserslautern, Erwin-Schrödinger-Str. 52–54, 67663 Kaiserslautern (Germany); Forschungszentrum OPTIMAS, Erwin-Schrödinger-Str. 46, 67663 Kaiserslautern (Germany); Thiel, W.R. [Fachbereich Chemie, Technische Universität Kaiserslautern, Erwin-Schrödinger-Str. 52–54, 67663 Kaiserslautern (Germany); Diller, R. [Fachbereich Physik, Technische Universität Kaiserslautern, Erwin-Schrödinger-Str. 46, 67663 Kaiserslautern (Germany)

    2014-10-17

    Graphical abstract: - Highlights: • Ultrafast dynamics of new Ru(II) catalysts investigated in gas phase and solution. • Catalyst activation (HCl loss) achieved in ion trap by UV photoexcitation. • Electronic relaxation proceeds by IVR and IC followed by ground state dissociation. • No triplet formation in contrast to other Ru-polypyridine complexes. • Solvent prohibits catalyst activation in solution by fast vibrational cooling. - Abstract: We report studies on the excited state dynamics of new ruthenium(II) complexes [(η{sup 6}-cymene)RuCl(apypm)]PF{sub 6} (apypm=2-NR{sub 2}-4-(pyridine-2-yl)-pyrimidine, R=CH{sub 3} (1)/H (2)) which, in their active form [1{sup +}-HCl] and [2{sup +}-HCl], catalyze the transfer hydrogenation of arylalkyl ketones in the absence of a base. The investigations encompass femtosecond pump–probe transient mass spectrometry under isolated conditions and transient absorption spectroscopy in acetonitrile solution, both on the cations [(η{sup 6}-cymene)RuCl(apypm)]{sup +} (1{sup +}, 2{sup +}). Gas phase studies on mass selected ions were performed in an ESI ion trap mass spectrometer by transient photofragmentation, unambiguously proving the formation of the activated catalyst species [1{sup +}-HCl] or [2{sup +}-HCl] after photoexcitation being the only fragmentation channel. The primary excited state dynamics in the gas phase could be fitted to a biexponential decay, yielding time constants of <100 fs and 1–3 ps. Transient absorption spectroscopy performed in acetonitrile solution using femtosecond UV/Vis and IR probe laser pulses revealed additional deactivation processes on longer time scales (∼7–12 ps). However, the formation of the active catalyst species after photoexcitation could not be observed in solution. The results from both studies are compared to former CID investigations and DFT calculations concerning the activation mechanism.

  4. Primate phylogeny studied by comparative determinant analysis. A preliminary report.

    Science.gov (United States)

    Bauer, K

    1993-01-01

    In this preliminary report the divergence times for the major primate groups are given, calculated from a study by comparative determinant analysis of 69 proteins (equaling 0.1% of the whole genetic information). With an origin of the primate order set at 80 million years before present, the ages of the last common ancestors (LCAs) of man and the major primate groups obtained this way are as follows: Pan troglodytes 5.2; Gorilla gorilla 7.4; Pongo pygmaeus 19.2; Hylobates lar 20.3; Old World monkeys 31.4; Lagothrix lagotricha 46.0; Cebus albifrons 59.5; three lemur species 67.0, and Galago crassicaudatus 73.3 million years. The LCA results and the approach are shortly discussed. A full account of this extended investigation including results on nonprimate mammals and on the determinant structures and the immunologically derived evolutionary rates of the proteins analyzed will be published elsewhere.

  5. PRELIMINARY STUDY OF EXTRACTABLE PROTEIN BINDING USING MALEIC ANHYDRIDE COPOLYMER

    Institute of Scientific and Technical Information of China (English)

    Thirawan Nipithakul; Ladawan Watthanachote; Nanticha Kalapat

    2012-01-01

    A preliminary study of using maleic anhydride copolymer for protein binding has been carried out.The polymeric films were prepared by compression of the purified resin and annealing the film to induce efficient back formation of the anhydride groups.The properties of the film surface were analyzed by attenuated total reflection Fourier transforms infrared spectroscopy and water contact angle measurements.The protein content was determined by Bradford assay.To obtain optimum conditions,immersion time for protein binding was examined.Results revealed that proteins can be successfully immobilized onto the film surface via covalent linkage.The efficiency of the covalent binding of the extractable protein to maleic anhydride-polyethylene film was estimated at 69.87 μtg/cm2,although the film had low anhydride content (3%) on the surface.

  6. Proscriptive Bayesian Programming and Maximum Entropy: a Preliminary Study

    Science.gov (United States)

    Koike, Carla Cavalcante

    2008-11-01

    Some problems found in robotics systems, as avoiding obstacles, can be better described using proscriptive commands, where only prohibited actions are indicated in contrast to prescriptive situations, which demands that a specific command be specified. An interesting question arises regarding the possibility to learn automatically if proscriptive commands are suitable and which parametric function could be better applied. Lately, a great variety of problems in robotics domain are object of researches using probabilistic methods, including the use of Maximum Entropy in automatic learning for robot control systems. This works presents a preliminary study on automatic learning of proscriptive robot control using maximum entropy and using Bayesian Programming. It is verified whether Maximum entropy and related methods can favour proscriptive commands in an obstacle avoidance task executed by a mobile robot.

  7. Mathematical modeling of normal pharyngeal bolus transport: a preliminary study.

    Science.gov (United States)

    Chang, M W; Rosendall, B; Finlayson, B A

    1998-07-01

    Dysphagia (difficulty in swallowing) is a common clinical symptom associated with many diseases, such as stroke, multiple sclerosis, neuromuscular diseases, and cancer. Its complications include choking, aspiration, malnutrition, cachexia, and dehydration. The goal in dysphagia management is to provide adequate nutrition and hydration while minimizing the risk of choking and aspiration. It is important to advance the individual toward oral feeding in a timely manner to enhance the recovery of swallowing function and preserve the quality of life. Current clinical assessments of dysphagia are limited in providing adequate guidelines for oral feeding. Mathematical modeling of the fluid dynamics of pharyngeal bolus transport provides a unique opportunity for studying the physiology and pathophysiology of swallowing. Finite element analysis (FEA) is a special case of computational fluid dynamics (CFD). In CFD, the flow of a fluid in a space is modeled by covering the space with a grid and predicting how the fluid moves from grid point to grid point. FEA is capable of solving problems with complex geometries and free surfaces. A preliminary pharyngeal model has been constructed using FEA. This model incorporates literature-reported, normal, anatomical data with time-dependent pharyngeal/upper esophageal sphincter (UES) wall motion obtained from videofluorography (VFG). This time-dependent wall motion can be implemented as a moving boundary condition in the model. Clinical kinematic data can be digitized from VFG studies to construct and test the mathematical model. The preliminary model demonstrates the feasibility of modeling pharyngeal bolus transport, which, to our knowledge, has not been attempted before. This model also addresses the need and the potential for CFD in understanding the physiology and pathophysiology of the pharyngeal phase of swallowing. Improvements of the model are underway. Combining the model with individualized clinical data should potentially

  8. Preliminaries toward studying resonant extraction from the Debuncher

    Energy Technology Data Exchange (ETDEWEB)

    Michelotti, Leo; Johnstone, John; /Fermilab

    2009-06-01

    A recent proposal to detect {mu} {yields} e direct conversion at Fermilab asks for slow extraction of protons from the antiproton source, specifically from the Debuncher. [1] A third-integer resonance originally was considered for this, partly because of the Debuncher's three-fold symmetry and partly because its operational horizontal tune, {nu}{sub x} {approx} 9.765, is already within 0.1 of {nu}{sub x} = 29/3. Using a half integer resonance, {nu}{sub x} = 19/2, though not part of the original proposal, has been suggested more recently because (a) Fermilab has had a good deal of experience with half-integer extraction from the Tevatron, the Main Injector and the erstwhile Main Ring, and (b) for reasons we shall examine later, it depopulates the entire bunch without an abort at the end. This memo presents considerations preliminary to studying both possibilities. It is meant only as a starting point for investigations to be carried out in the future. The working constraints and assumptions have oscillated between two extremes: (1) making minimal changes in the antiproton source to minimize cost and (2) building another machine in the same tunnel. In this memo we adopt an attitude aligned more toward the first. The assumed parameters are listed in Table 1. A few are not (easily) subject to change, such as those related to the beam's momentum and revolution frequency and the acceptance of the debuncher. Two resonance exemplars are presented in the next section, with an explanation of the analytic and semi-analytic calculations that can be done for each. Section 3 contains preliminary numerical work that was done to validate the exemplars within the context of extraction from the Debuncher. A final section contains a summary. Following the bibliography, appendices contain (a) a qualitative, conceptual discussion of extraction for the novice, (b) a telegraphic review of the perturbative incantations used to filter the exemplars as principal resonances of

  9. Transient lingual papillitis: A retrospective study of 11 cases and review of the literature

    Science.gov (United States)

    Tosios, Konstantinos I.; Nikitakis, Nikolaos G.; Kamperos, Georgios; Sklavounou, Alexandra

    2017-01-01

    Background Transient lingual papillitis (TLP) is a common, under-diagnosed, inflammatory hyperplasia of one or multiple fungiform lingual that has an acute onset, and is painful and transient in nature. Material and Methods Eleven cases of TLP were diagnosed based on their clinical features. Information on demographics, clinical characteristics, symptoms, individual or family history of similar lesions, medical history, management and follow-up were extracted from the patients’ records. The English literature was reviewed on TLP differential diagnosis, pathogenesis and management. Results The study group included 8 females and 3 males (age: 10-53 years, mean age 31.7±12.88 years). Seven cases were classified as generalized form of TLP and 4 as localized form. Nine cases were symptomatic. Time to onset ranged from 1 to 14 days. A specific causative factor was not identified in any case and management was symptomatic. Conclusions Although TLP is not considered as a rare entity, available information is limited. Diagnosis is rendered clinically, while biopsy is required in cases with a differential diagnostic dilemma. TLP should be included in the differential diagnosis of acute, painful tongue nodules. Key words:Transient lingual papillitis, fungiform papillary glossitis, tongue, nodules. PMID:28149482

  10. Algorithm study of transient response of vertical magnetic bipolar source in whole space plane layered medium

    Institute of Scientific and Technical Information of China (English)

    HU Bo; YUE Jian-hua; YANG Hai-yan

    2009-01-01

    For some time, whole space feature as a theoretical problem has been a puzzle in mining transient electromagnetic method (TEM). We have introduced a detailed method of calculating the transient response of a vertical magnetic bipolar source in a whole space plane layered medium in order to obtain whole space features. After designing a whole space plane layered medium model, equations were established based on boundary conditions in terms of electromagnetic vector potential. Expressions of electromag-netic fields were obtained by solving these equations. The expressions were computed by the Hankel transform after dispersion. The results in a frequency domain were changed into a time domain by using a multinomial cosine transform method. The expressions were correctly validated by comparing them with the analytical solution in half space. The half space and whole space results show that the whole space features are clear, suggesting that the theory of half space is not suitable for the whole space. Our algorithm supplied the technical instrument for studying the distributed features of whole space transient electromagnetic fields.

  11. Study on acoustical properties of sintered bronze porous material for transient exhaust noise of pneumatic system

    Science.gov (United States)

    Li, Jingxiang; Zhao, Shengdun; Ishihara, Kunihiko

    2013-05-01

    A novel approach is presented to study the acoustical properties of sintered bronze material, especially used to suppress the transient noise generated by the pneumatic exhaust of pneumatic friction clutch and brake (PFC/B) systems. The transient exhaust noise is impulsive and harmful due to the large sound pressure level (SPL) that has high-frequency. In this paper, the exhaust noise is related to the transient impulsive exhaust, which is described by a one-dimensional aerodynamic model combining with a pressure drop expression of the Ergun equation. A relation of flow parameters and sound source is set up. Additionally, the piston acoustic source approximation of sintered bronze silencer with cylindrical geometry is presented to predict SPL spectrum at a far-field observation point. A semi-phenomenological model is introduced to analyze the sound propagation and reduction in the sintered bronze materials assumed as an equivalent fluid with rigid frame. Experiment results under different initial cylinder pressures are shown to corroborate the validity of the proposed aerodynamic model. In addition, the calculated sound pressures according to the equivalent sound source are compared with the measured noise signals both in time-domain and frequency-domain. Influences of porosity of the sintered bronze material are also discussed.

  12. Preliminary studies on the optimization of countermeasures for agricultural areas

    Energy Technology Data Exchange (ETDEWEB)

    Rochedo, Elaine R.R.; Igreja, Eduardo; Barboza, Adriana E., E-mail: elainerochedo@gmail.com, E-mail: eduigreja@gmail.com, E-mail: adrianaebarboza@gmail.com [Instituto Militar de Engenharia (IME), Rio de Janeiro, RJ (Brazil); Silva, Diogo N.G. da; Guimaraes, Jean R.D., E-mail: diogons@gmail.com, E-mail: jeanrdg@biof.ufrj.br [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Instituto de Biofisica Carlos Chagas Filho; Wasserman, Maria Angelica V., E-mail: mwasserman@ien.gov.br [Instituto de Engenharia Nuclear (IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Perez, Daniel V. [Centro Nacional de Pesquisa de Solos (EMBRAPA), Rio de Janeiro, RJ (Brazil)

    2015-07-01

    The assessment of remediation measures for rural areas is more complex than that for urban ones, due to the influence of large number of variables associated with climate, diet, farming practices and the type of soil. Thus, it is not possible to perform generic studies applicable to all types of area. Specific studies and surveys should be made in the areas most likely to contamination from a nuclear accident. Preliminary studies demonstrated that the different soil types in Brazil is more relevant to the ingestion dose than the regional differences in diets. Other studies have described the prioritization of areas and products for detailed survey on soil types and remediation procedures, for an accident at the NPP in Angra dos Reis, based on radiological and economic aspects. The most relevant product was milk, due to both its relevance to the intake and the loss of income for the counties. The contribution of milk to dose depends on the season of the year when the accident occurs, mainly due to the relative contribution of other items of the diet. The timing of the application of the countermeasure has an important effect on the dose reduction that can be achieved. For I-131, protective measures must be considered within the emergency phase in order to be effective. The main action on reducing ingestion doses is the removal of food items from diet, while providing clean food to the population. (author)

  13. Preliminary studies to determine the shelf life of HEPA filters

    Energy Technology Data Exchange (ETDEWEB)

    Gilbert, H.; Fretthold, J.K.; Rainer, F. [Lawrence Livermore National Laboratory, CA (United States)] [and others

    1995-02-01

    We have completed a preliminary study using filter media tests and filter qualification tests to investigate the effect of shelf-life on HEPA filter performance. Our media studies showed that the tensile strength decreased with age, but the data were not sufficient to establish a shelf-life. Thermogravimetric analyses demonstrated that one manufacturer had media with low tensile strength due to insufficient binder. The filter qualification tests (heated air and overpressure) conducted on different aged filters showed that filter age is not the primary factor affecting filter performance; materials and the construction design have a greater effect. An unexpected finding of our study was that sub-standard HEPA filters have been installed in DOE facilities despite existing regulations and filter qualification tests. We found that the filter with low tensile strength failed the overpressure test. The same filter had passed the heated air test, but left the filter so structurally weak, it was prone to blow-out. We recommend that DOE initiate a filter qualification program to prevent this occurrence.

  14. Caligula-Christ: Preliminary Study of a Parallel

    Directory of Open Access Journals (Sweden)

    Lorene M. Birden

    2010-01-01

    Full Text Available Caligula, at the very beginning of the Albert Camus play, conceives a very ambitious project; to surpass the gods and take their place in his empire, in order to decree impossibility. Camus has, however, gone a step further in developing the god-image of his main character through the incorporation of much Christian imagery into the scenes. This aspect of the play seems not to have been noticed by Camus scholars; there is no in-depth study of the use of this imagery. However, Camus scholar Patricia Johnson and the members of the Société des études camusiennes have noted the usefulness of the analysis presented here and the absence of it in previous research. This study, designated as “preliminary,” attempts to prompt further analyses of the question and offers different approaches. It proceeds by intertextual study of Caligula and the gospels (here referred to in Revised Standard Version and brings out aspects of the emperor’s intentions that expose a combination of perversion and similarity in relation to deity. It briefly outlines the sources of this parallel and the reasons for creating it, then details the parallels that show first the reversal of the image of Jesus, then the striking consonance. It ends with interpretations of the parallels and concludes with commentaries on the use of irony to create them.

  15. Study of transient wave propagation in plates using double pulse TV holography

    OpenAIRE

    Lopes, H.; Guedes, R. M.; M. A. P. Vaz; Rodrigues, J.D.

    2004-01-01

    This work presents a numerical and experimental study of the transient response of an isotropic plate. A low mass impact is used to generate the bending wave propagation. Displacements due to the bending wave propagation were assessed using an out-of-plane double pulse TV holography set-up. A PZT transducer is used to record the impact force and its temporal evolution. A novel experimental technique is presented for determination of the stress field in the plate using the out-of-plane ...

  16. NUMERICAL STUDY OF TRANSIENT THREE-DIMENSIONAL HEAT CONDUCTION PROBLEM WITH A MOVING HEAT SOURCE

    Directory of Open Access Journals (Sweden)

    Marko V Miloš

    2011-01-01

    Full Text Available A numerical study of transient three-dimensional heat conduction problem with a moving source is presented. For numerical solution Douglas-Gunn alternating direction implicit method is applied and for the moving heat source flux distribution Gaussian function is used. An influence on numerical solution of input parameters figuring in flux boundary conditions is examined. This include parameters appearing in Gaussian function and heat transfer coefficient from free convection boundaries. Sensitivity of cooling time from 800 to 500 °C with respect to input parameters is also tested.

  17. Dynamic study in partial transient liquid phase bonding of Si3N4

    Institute of Scientific and Technical Information of China (English)

    邹家生; 初雅杰; 许志荣; 陈光

    2004-01-01

    Dynamics in partial transient liquid phase bonding (PTLP bonding) of Si3N4 ceramic with Ti/Cu/Ti multi-interlayer was systematically studied through micro-analysis of joint interfaces. The results show that growth of reaction layer and isothermal solidification procession do at the same time. Growth of reaction layer and moving of isothermal solidification interface obey the parabolic law governed by the diffusion of participating elements during the PTLP bonding. Coordination of the above two dynamics process is done through time and temperature. When reaction layer thickness is suitable and isothermal solidification process is finished, the high bonding strength at room temperature and high temperature are obtained.

  18. Excited-state symmetry breaking of linear quadrupolar chromophores: A transient absorption study

    Science.gov (United States)

    Dozova, Nadia; Ventelon, Lionel; Clermont, Guillaume; Blanchard-Desce, Mireille; Plaza, Pascal

    2016-11-01

    The photophysical properties of two highly symmetrical quadrupolar chromophores were studied by both steady-state and transient absorption spectroscopy. Their excited-state behavior is dominated by the solvent-induced Stokes shift of the stimulated-emission band. The origin of this shift is attributed to symmetry breaking that confers a non-vanishing dipole moment to the excited state of both compounds. This dipole moment is large and constant in DMSO, whereas symmetry breaking appears significantly slower and leading to smaller excited-state dipole in toluene. Time-dependant increase of the excited-state dipole moment induced by weak solvation is proposed to explain the results in toluene.

  19. A case-crossover study of transient risk factors influence on occupational injuries

    DEFF Research Database (Denmark)

    Oesterlund, Anna H; Lander, Flemming; Lauritsen, Jens

    2016-01-01

    BACKGROUND: The occupational injury incident rate remains relatively high in the European Union. The case-crossover study gives a unique opportunity to study transient risk factors that normally would be very difficult to approach. Studies like this have been carried out in both America and Asia......, but so far no relevant research has been conducted in Europe. METHOD: Case-crossover studies of occupational injuries were collected from PubMed and Embase and read through. Previous experiences concerning method, exposure and outcome, time-related measurements and construction of the questionnaire were...... taken into account in the preparation of a pilot study. Consequently, experiences from the pilot study were used to design the study protocol. Approximately 2000 patients with an occupational injury will be recruited from the emergency departments in Herning and Odense, Denmark. A standardised...

  20. A Preliminary Study on Gender Differences in Studying Systems Analysis and Design

    Science.gov (United States)

    Lee, Fion S. L.; Wong, Kelvin C. K.

    2017-01-01

    Systems analysis and design is a crucial task in system development and is included in a typical information systems programme as a core course. This paper presented a preliminary study on gender differences in studying a systems analysis and design course of an undergraduate programme. Results indicated that male students outperformed female…

  1. Wastewater characterization of IPEN facilities - a preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Monteiro, Lucilena R.; Goncalves, Cristina; Terazan, Wagner R.; Cotrim, Marycel E.B.; Pires, Maria Aparecida F., E-mail: lrmonteiro@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    As part of IPEN's Environmental Monitoring Program, wastewater sample collection and analysis was implemented on a daily basis. CQMA- Centro de Quimica e Meio Ambiente was responsible for the determination of total, fixed and volatile solids, pH, metals (as Al, Sb, Ba, Cd, Pb, Co, Cu, Cr, Hg, Mo, Ni, Ag, Na, Zn, Ca, Mg, Be, Sn, Li, K, Sr, Ti and V), semimetals (As, B, Se and Si) and anions (such as chloride, nitrate, sulfate and fluoride). The results were compared to the legal values established by the Sao Paulo State regulation 8,468/76, which defines the maximum permitted values for most of the studied substances in wastewater, aiming its releasing in public wastewater treatment system. The evaluation of this parameters concentration on Ipen's effluent implies that 50% of the wastewater corresponds to organic matter due to the sanitary load and inorganic macro elements, mainly as sodium, potassium, calcium. The only parameter not found in accordance with Brazilian legislation was pH in four out of the one hundred and seven samples collected throughout 2009 (2.8% of the samples analyzed). This preliminary study showed the effluents generated at Ipen's facility is characterized by the presence of organic matter and macro elements, commonly found in sanitary wastewater and it is in compliance with Sao Paulo regulations. (author)

  2. Effects of gamma radiation on bee venom: preliminary studies

    Energy Technology Data Exchange (ETDEWEB)

    Costa, H.; Boni-Mitake, M.; Souza, C.F.; Rogero, J.R. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil). Div. de Radiobiologia

    1999-11-01

    Africanized honeybees are very common insects in Brazil and frequently cause accidents followed by important immunological reactions and even deaths. Their venoms are composed of a complex mixture of substances of general biological actions. several works utilizing ionizing radiation showed that it is able to modify protein structures, and successfully detoxify snake venoms toxins, although maintaining its immunological properties. The main objective of this paper was to study the effects of gamma radiation on bee venom, regarding some biochemical and toxicological aspects. Africanized Apis melllifera whole venom (2 mg/ml) in 0.15 M Na Cl solution was irradiated with 2 kGy in a {sup 60} Co source. Preliminary studies has been carried out in order to identify some biochemical changes after irradiation. Concerning this, irradiated and native venom were submitted to a molecular exclusion chromatography (Sephadex G-100), UV absorption spectrum and protein concentration analysis. It could be seen that irradiated bee venom spectrum presented differences when compared to native bee venom, suggesting that some structural alterations has occurred. Protein concentration and chromatography profiles were not changes after irradiation. In order to evaluate the toxicity a lethality assay (L D{sub 50}) has been performed with both venoms, and irradiated venom showed to be less toxic than native one. (author) 23 refs., 3 figs., 1 tab.

  3. Thulium-170-labeled microparticles for local radiotherapy: preliminary studies.

    Science.gov (United States)

    Polyak, Andras; Das, Tapas; Chakraborty, Sudipta; Kiraly, Reka; Dabasi, Gabriella; Joba, Robert Peter; Jakab, Csaba; Thuroczy, Julianna; Postenyi, Zita; Haasz, Veronika; Janoki, Gergely; Janoki, Gyozo A; Pillai, Maroor R A; Balogh, Lajos

    2014-10-01

    The present article describes the preparation, characterization, and biological evaluation of Thulium-170 ((170)Tm) [T1/2 = 128.4 days; Eβmax = 968 keV; Eγ = 84 keV (3.26%)] labeled tin oxide microparticles for its possible use in radiation synovectomy (RSV) of medium-sized joints. (170)Tm was produced by irradiation of natural thulium oxide target. 170Tm-labeled microparticles were synthesized with high yield and radionuclidic purity (> 99%) along with excellent in vitro stability by following a simple process. Particle sizes and morphology of the radiolabeled particles were examined by light microscope, dynamic light scattering, and transmission electron microscope and found to be of stable spherical morphology within the range of 1.4-3.2 μm. The preparation was injected into the knee joints of healthy Beagle dogs intraarticularly for biological studies. Serial whole-body and regional images were taken by single-photon-emission computed tomography (SPECT) and SPECT-CT cameras up to 9 months postadministration, which showed very low leakage (< 8% of I.D.) of the instilled particles. The majority of leaked radiocolloid particles were found in inguinal lymph nodes during the 9 months of follow-up. All the animals tolerated the treatment well; the compound did not show any possible radiotoxicological effect. These preliminary studies showed that 170Tm-labeled microparticles could be a promising nontoxic and effective radiopharmaceutical for RSV applications or later local antitumor therapy.

  4. A Preliminary Study of Bryophytes in Enggano Island, Bengkulu, Indonesia

    Directory of Open Access Journals (Sweden)

    Ainun Nadhifah

    2016-09-01

    Full Text Available Enggano Island is one of the outer islands  that belongs to the Province of Bengkulu. Furthermore, there is very limited information about the diversity of bryophyte from Sumatera, especially in lowland forest, Enggano Island. The aim of this research was to provide the initial information related to the diversity of bryophytes in Enggano. The research was conducted in six forests i.e. primary, secondary and degraded forests. The results showed that 32 number of collection from 14 families, 21 genera, and 32 species were identified. Leceuneaceae was common family for liverworts while the mosses family was dominated by Hypnaceae. None of the hornworts were found in this study. Some species identified (Taxyphyllum sp., Vesicularia sp., Riccardia sp., and Thuidium sp. have the potential benefit and biological activity. Two genera were new records to Sumatra, Gongylanthus, and Symphyogyna. Moreover, Gongylanthus sp. and Symphyogyna sp. have important records related to the habitat.How to CiteNadhifah, A., & Surya, M. I. (2016. A Preliminary Study of Bryophytes in Enggano Island, Bengkulu, Indonesia. Biosaintifika: Journal of Biology & Biology Education, 8(2, 201-205.

  5. Preliminary Study of the Gravimetric Local Geoid Model in Jordan:

    Directory of Open Access Journals (Sweden)

    A. Al-Zoubi

    2007-06-01

    Full Text Available Recently, there is an increased interest in studying and defining the Local and Regional Geoid Model worldwide, due to its importance in geodetic and geophysics applications. The use of the Global Positioning System (GPS is internationally growing, yet the lack of any Geoid Model for Jordan has limited the use of GPS for geodetic applications. Therefore, this work aims to present the preliminary results that we propose for The Gravimetric Jordanian Geoid Model (GeoJordan. The model is created using gravimetric data and the GravSoft program. The validation of this model is done by using GPS measurements and precise leveling at Amman area. However, a comparison between the Global Geopotential Models OSU91A and EGM96 showed great discrepancies through the presented results. Also, presenting the approach used to obtain the orthometric height from GPS ellipsoidal height measurements. Nevertheless, the error margin; obtained in this initial study of the GeoJordan after fitting the data with GPS/leveling measurement; is about (10cm, in tested area whereas the standard error of the created model is about (40cm.

  6. A framework for studying transient dynamics of population projection matrix models

    DEFF Research Database (Denmark)

    Stott, Iain; Townley, Stuart; Hodgson, David James

    2011-01-01

    arise even from simple models following ecological disturbances or perturbations. Recent interest in such transient dynamics has led to diverse methodologies for their quantification in density-independent, time-invariant population projection matrix (PPM) models, but the fragmented nature...... of this literature has stifled the widespread analysis of transients. We review the literature on transient analyses of linear PPM models and synthesise a coherent framework. We promote the use of standardised indices, and categorise indices according to their focus on either convergence times or transient...... population density, and on either transient bounds or case-specific transient dynamics. We use a large database of empirical PPM models to explore relationships between indices of transient dynamics. This analysis promotes the use of population inertia as a simple, versatile and informative predictor...

  7. Calendar effect on phase study in paleoclimate transient simulation with orbital forcing

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Guang-Shan [Chinese Academy of Sciences, SKLLQG, Institute of Earth Environment, Xi' an (China); University of Wisconsin, Center for Climate Research, Madison, WI (United States); Kutzbach, J.E.; Gallimore, R.; Liu, Zhengyu [University of Wisconsin, Center for Climate Research, Madison, WI (United States)

    2011-11-15

    Several studies have shown that the use of different calendars in paleoclimate simulations can cause artificial phase shifts on insolation forcing and climatic responses. However, these important calendar corrections are still often neglected. In this paper, the phase shifts at the precession band is quantitatively assessed by converting the model data of the transient GCM climate simulation of Kutzbach et al. (Clim Dyn 30:567-579, 2008) from the ''fixed-day'' calendar to the ''fixed-angular'' calendar with a new and efficient approach. We find that insolation has a big phase shift in September-October-November (SON) when the vernal equinox (VE) is fixed to March 21. At high latitude, the phase bias is up to 60 (about 3650 years). The insolation phase bias in SON in Southern Hemisphere (SH) is especially important because it can influence the timing of the SH summer monsoon response due to the large heat capacity of ocean. The calendar correction has minor effect ({+-}2 ) on the phase relationships between forcing and precipitation responses of the six global summer monsoons studied in Kutzbach et al. (2008). After correcting the calendar effect, especial on SH ocean temperature, the new phase wheel results are more similar for both hemispheres. The results suggest that the calendar effect should be corrected before discussing the dynamics between orbital forcing and climatic responses in phase studies of transient simulations. (orig.)

  8. Device Optimization and Transient Electroluminescence Studies of Organic light Emitting Devices

    Energy Technology Data Exchange (ETDEWEB)

    Lijuan Zou

    2003-08-05

    Organic light emitting devices (OLEDs) are among the most promising for flat panel display technologies. They are light, bright, flexible, and cost effective. And while they are emerging in commercial product, their low power efficiency and long-term degradation are still challenging. The aim of this work was to investigate their device physics and improve their performance. Violet and blue OLEDs were studied. The devices were prepared by thermal vapor deposition in high vacuum. The combinatorial method was employed in device preparation. Both continuous wave and transient electroluminescence (EL) were studied. A new efficient and intense UV-violet light emitting device was developed. At a current density of 10 mA/cm{sup 2}, the optimal radiance R could reach 0.38 mW/cm{sup 2}, and the quantum efficiency was 1.25%. using the delayed EL technique, electron mobilities in DPVBi and CBP were determined to be {approx} 10{sup -5} cm{sup 2}/Vs and {approx} 10{sup -4} cm{sup 2}/Vs, respectively. Overshoot effects in the transient El of blue light emitting devices were also observed and studied. This effect was attributed to the charge accumulation at the organic/organic and organic/cathode interfaces.

  9. THE STUDY OF TRANSIENT PROCESSES OF THE FREQUENCY-REGULATED SYNCHRONOUS ELECTRIC DRIVE

    Directory of Open Access Journals (Sweden)

    B. I. Firago

    2016-01-01

    Full Text Available In order to improve the power indices and to simplify the system of frequency speed control the scope of application of synchronous variable-frequency electric drives with independent frequency setting is being expanded. The synchronous motors with electromagnetic excitation and permanent magnet excitation in various industrial settings, including load-lifting machines and mechanisms, are used. As compared with the asynchronous frequency-regulated electric drives the synchronous ones have lower power loss, harder mechanical characteristic without feedback for speed and the simplest law of frequency control, i. e., a proportional one that, however, provides the maximum electromagnetic torque of the motor constant at all frequencies, due to the constant magnetic flux. The article concerns an analytical study of transient processes of synchronous electric drive with consideration of the influence of damping winding when the motor supply voltage frequency varies linearly during the transient time. As a result of the analysis the formulas have been obtained that make it possible to calculate the angular velocity of the rotor and the electromagnetic torque of the motor at start-up, braking, and impingement and discharge of loads, evaluating the quality of the transition process and tracking the maximum value of the electromagnetic torque, that must not exceed the permissible value. Validation of the developed technique of calculation of transient processes of synchronous electric drive has been obtained by comparison of calculations according to the formulas with the simulation results of the electric drive on the basis of the synchronous motor of the SD3 13-34-6 type (power of 500 kW and voltage of 6 kV.

  10. ECG response of koalas to tourists proximity: a preliminary study.

    Directory of Open Access Journals (Sweden)

    Yan Ropert-Coudert

    Full Text Available Koalas operate on a tight energy budget and, thus, may not always display behavioral avoidance reaction when placed in a stressful condition. We investigated the physiological response of captive koalas Phascolarctos cinereus in a conservation centre to the presence of tourists walking through their habitat. We compared, using animal-attached data-recorders, the electrocardiogram activity of female koalas in contact with tourists and in a human-free area. One of the koalas in the tourist zone presented elevated heart rate values and variability throughout the recording period. The remaining female in the exhibit area showed a higher field resting heart rates during the daytime than that in the isolated area. In the evening, heart rate profiles changed drastically and both the koalas in the exhibit and in the tourist-free zones displayed similar field resting heart rates, which were lower than those during the day. In parallel, the autonomic nervous systems of these two individuals evolved from sympathetic-dominant during the day to parasympathetic-dominant in the evening. Our results report ECG of free-living koalas for the first time. Although they are preliminary due to the difficulty of having sufficient samples of animals of the same sex and age, our results stress out the importance of studies investigating the physiological reaction of animals to tourists.

  11. Textual appropriation in engineering master's theses: a preliminary study.

    Science.gov (United States)

    Eckel, Edward J

    2011-09-01

    In the thesis literature review, an engineering graduate student is expected to place original research in the context of previous work by other researchers. However, for some students, particularly those for whom English is a second language, the literature review may be a mixture of original writing and verbatim source text appropriated without quotations. Such problematic use of source material leaves students vulnerable to an accusation of plagiarism, which carries severe consequences. Is such textual appropriation common in engineering master's writing? Furthermore, what, if anything, can be concluded when two texts have been found to have textual material in common? Do existing definitions of plagiarism provide a sufficient framework for determining if an instance of copying is transgressive or not? In a preliminary attempt to answer these questions, text strings from a random sample of 100 engineering master's theses from the ProQuest Dissertations and Theses database were searched for appropriated verbatim source text using the Google search engine. The results suggest that textual borrowing may indeed be a common feature of the master's engineering literature review, raising questions about the ability of graduate students to synthesize the literature. The study also illustrates the difficulties of making a determination of plagiarism based on simple textual similarity. A context-specific approach is recommended when dealing with any instance of apparent copying.

  12. Lymphangiogenesis in Classical Hodgkin Lymphoma - Preliminary Study with Clinicopathological Correlations

    Science.gov (United States)

    Benharroch, Daniel; Prinsloo, Isebrand; Gopas, Jacob; Lazarev, Irena

    2016-01-01

    A role for lymphangiogenesis in metastatic breast and prostate cancers has been suggested recently. The relevance of lymphangiogenesis in cancer as a rule, and more specifically in classical Hodgkin lymphoma, is poorly understood in comparison with that of angiogenesis. In a preliminary (pilot) study we have investigated the role of lymphatic vessels growth in 19 cases of classical Hodgkin lymphoma stained with the D2-40 (podoplanin) antibody. In each case, three lymphatic vessels hot spots were scrutinized twice. Of the 57 hot spots thus identified, we chose 15 at random for photography, microvessel counting and image analysis. We determined the mean perimeter, surface area, major axis length and complexity factor for each hot spot and correlated them with clinical and biological features of classical Hodgkin lymphoma. No correlations were found with clinical features. No associations were noted with the standard immuno-markers of classical Hodgkin lymphoma. However, significant inverse correlations were shown with pRb, BAX and IκB-α expression. The mean lymphatic major axis length was inversely correlated with the complexity factor. Last, we carried out an additional clinicopathological correlation of the expression of pRb, BAX and IκB-α in a cohort of classical Hodgkin lymphoma patients previously published. PMID:27877228

  13. Studying the anthropogenic radionuclides in Puerto Rico: Preliminary Result

    Science.gov (United States)

    Ithier-Guzmán, W.; Pyrtle, A. J.; Smoak, J.

    2004-12-01

    Local introduction of anthropogenic radionuclides to Puerto Rico's terrestrial and aquatic environments began in 1962 as a result of US government-sponsored research activities. Some of the earlier experiments examined the effects of radiation in tropical rainforests and the potential of superheated boiling nuclear reactor technology. More recent activities involved the use of depleted uranium during military exercises on Vieques. While the presence of radionuclides in Puerto Rico is documented, little research has been done to assess the environmental impact of this anthropogenic material. After entering Puerto Rico's environment, it is likely that some radionuclides are transported away from initial introduction sites. It is important that the distributions and behavior of radionuclides in Puerto Rico be determined. As such an investigation of this material throughout Puerto Rico was initiated. Sediment Cs-137 and Pb-210 activities, as well as ancillary geochemistry data are presented. These preliminary findings will be utilized as part of an ongoing study to determine radionuclide distributions and behaviors, with respect to aquatic geochemistry and dominant transport processes.

  14. Preliminary Design Study of the Hollow Electron Lens for LHC

    CERN Document Server

    Perini, Diego; CERN. Geneva. ATS Department

    2017-01-01

    A Hollow Electron Lens (HEL) has been proposed in order to improve performance of halo control and collimation in the Large Hadron Collider in view of its High Luminosity upgrade (HL-LHC). The concept is based on a beam of electrons that travels around the protons for a few meters. The electron beam is produced by a cathode and then guided by a strong magnetic field generated by a set of superconducting solenoids. The first step of the design is the definition of the magnetic fields that drive the electron trajectories. The estimation of such trajectories by means of a dedicated MATLAB® tool is presented. The influence of the main geometrical and electrical parameters are analysed and discussed. Then, the main mechanical design choices for the solenoids, cryostats gun and collector are described. The aim of this paper is to provide an overview of the preliminary design of the Electron Lens for LHC. The methods used in this study also serve as examples for future mechanical and integration designs of similar ...

  15. Preliminary Study on Diverse Carbon Utilization by Transformant Aspergillus niger

    Directory of Open Access Journals (Sweden)

    S. H. Mohammad

    2012-01-01

    Full Text Available Aspergillus niger have been widely recognized as producer of metabolites and reported as good expression hosts for homologous and heterologous proteins. For recombinant expression systems, nature of metabolite production would change when the expression host system is modified via plasmid development. In order to study the diversity of carbon utilization of transformant A.niger and their relation to specific carbon sources that could trigger mannanase production, a new screening system was introduced using Biolog technique to evaluate the growth of the transformant performed on 95 carbon sources. As a result, the transformed A.niger were found able to utilize dextrin and other 27 carbohydrates with majority preferred carbohydrates were identified as monosaccharide, oligosaccharides and some sugar alcohols as the best chosen carbon sources for growth. The relative simplicity and global carbon sources underlying in the biolog system for screening of carbon source make it as a useful tool for the preliminary screening and identification of carbon sources in order to select the best carbon source for medium development.

  16. Calibration Study and Preliminary Results of PRad Experiment

    Science.gov (United States)

    Levillain, Maxime; PRad Collaboration

    2016-09-01

    The latest measurements of the proton radius through muonic hydrogen Lamb shift show a discrepancy of 7 σ from a global analysis of standard hydrogen Lamb shift and elastic ep -scattering. In order to understand this proton radius puzzle, the PRad experiment successfully took in last June some elastic ep -scattering data at very low Q2 (2 .10-4 to 10-1 GeV2) with very accurate angle and energy measurements to minimize the systematic uncertainties. Before measuring the cross-sections that will be used to extract the electromagnetic form factor GE(Q2) and the proton radius, a very careful calibration of the electromagnetic calorimeter (HyCal) must be performed to get a good energy resolution and separate ep -events from M øller events especially at low angle. We will present an extended study of the electromagnetic calorimeter calibration of this experiment as well as some preliminary results on ep - and ee -scattering processes extracted from the data. The PRad experiment is supported in part by NSF MRI Award PHY-1229153.

  17. A preliminary study looking at parental emotions following cochlear implantation.

    Science.gov (United States)

    Anagnostou, Flora; Graham, John; Crocker, Susan

    2007-06-01

    This preliminary research investigated the emotions of parents with cochlear implanted children. The object for the research was first to compare four emotions engendered in parents of deaf children before and after cochlear implantation. Second, to monitor changes in these emotions during a period of up to four years after implantation. Third, to see whether any of the emotions studied was significantly more prominent than the others, and fifth to identify any differences in emotions that were related to the gender of parents. A self-report questionnaire was given to 112 participants of whom 53 replied. There were equal groups of parents in two categories, those with children up to two years after implantation, and those two to four years after implantation. The responses were interpreted using parametric statistics. The results highlight that grief is the strongest emotional condition that parents experience before and up to two years after implantation, alongside family adjustments. Parents of the up to two years after implantation group generally have stronger feelings and are less satisfied than parents in the over two years implanted group. Finally, fathers use denial more than mothers. Considerations for future research and implications for paediatric cochlear implant teams will be discussed.

  18. ECG response of koalas to tourists proximity: a preliminary study.

    Science.gov (United States)

    Ropert-Coudert, Yan; Brooks, Lisa; Yamamoto, Maki; Kato, Akiko

    2009-10-12

    Koalas operate on a tight energy budget and, thus, may not always display behavioral avoidance reaction when placed in a stressful condition. We investigated the physiological response of captive koalas Phascolarctos cinereus in a conservation centre to the presence of tourists walking through their habitat. We compared, using animal-attached data-recorders, the electrocardiogram activity of female koalas in contact with tourists and in a human-free area. One of the koalas in the tourist zone presented elevated heart rate values and variability throughout the recording period. The remaining female in the exhibit area showed a higher field resting heart rates during the daytime than that in the isolated area. In the evening, heart rate profiles changed drastically and both the koalas in the exhibit and in the tourist-free zones displayed similar field resting heart rates, which were lower than those during the day. In parallel, the autonomic nervous systems of these two individuals evolved from sympathetic-dominant during the day to parasympathetic-dominant in the evening. Our results report ECG of free-living koalas for the first time. Although they are preliminary due to the difficulty of having sufficient samples of animals of the same sex and age, our results stress out the importance of studies investigating the physiological reaction of animals to tourists.

  19. VEGF Expression in Patellar Tendinopathy: A Preliminary Study

    Science.gov (United States)

    Lian, Øystein; Bahr, Roald; Hart, David A.; Duronio, Vincent

    2008-01-01

    Vascular function and angiogenesis are regulated by vascular endothelial growth factor-A (VEGF). The purpose of this preliminary study was to address the following questions: Is VEGF expression in the patellar tendon more prevalent in patients with patellar tendinopathy than in individuals with normal, pain-free patellar tendons? Which cell populations express VEGF in normal and tendinopathic tendon? Is there a difference in symptom duration between VEGF+ and VEGF− tendons? We collected patellar tendon tissue from 22 patients undergoing open débridement of the patellar tendon and from 10 patients undergoing intramedullary nailing of the tibia. VEGF expression was assessed immunohistochemically. Relevant inflammatory and repair cell types were immunolabeled. VEGF expression was absent from control tendons, but was present in a subset of patients with histopathological evidence of angiofibroblastic tendinosis. VEGF was expressed in the intimal layer of tendon vessels, but was absent in other cell types. Patients demonstrating VEGF expression in the patellar tendon had a shorter symptom duration (12 ± 7.8 months) than patients with no detectable VEGF (32.8 ± 23.5 months). VEGF may contribute to the vascular hyperplasia that is a cardinal feature of symptomatic tendinosis, particularly in cases with more recent onset. PMID:18459027

  20. Platform for dynamic tests: preliminary studies, design and construction

    Directory of Open Access Journals (Sweden)

    J. E. Campuzano

    . The platform was built and has been done a preliminary experimental study to obtain the first natural frequencies.

  1. Bio-Contamination Control for Spacesuit Garments - A Preliminary Study

    Science.gov (United States)

    Rhodes, Richard; Korona, Adam; Orndoff, Evelyn; Ott, Mark; Poritz, Darwin

    2010-01-01

    This paper outlines a preliminary study to review, test, and improve upon the current state of spacesuit bio-contamination control. The study includes an evaluation of current and advanced suit materials, ground and on-orbit cleaning methods, and microbial test and analysis methods. The first aspect of this study was to identify potential anti-microbial textiles and cleaning agents, and to review current microbial test methods. The anti-microbial cleaning agent and textile market survey included a review of current commercial-off-the-shelf (COTS) products that could potentially be used as future space flight hardware. This review included replacements for any of the softgood layers that may become contaminated during an extravehicular activity (EVA), including the pressure bladder, liquid cooling garment, and ancillary comfort undergarment. After a series of COTS anti-microbial textiles and clean ing agents were identified, a series of four tests were conducted: (1) a stacked configuration test that was conducted in order to review how bio-contamination would propagate through the various suit layers, (2) a individual materials test that evaluated how well each softgood layer either promoted or repressed growth, (3) a cleaning agent test that evaluated the efficacy on each of the baseline bladders, and (4) an evaluation of various COTS anti-microbial textiles. All antimicrobial COTS materials tested appeared to control bacteria colony forming unit (CFU) growth better than the Thermal Comfort Undergarment (TCU) and ACES Liquid Cooling Garment (LCG)/EMU Liquid Cooling Ventilation Garment (LCVG) materials currently in use. However, a comparison of fungi CFU growth in COTS to current suit materials appeared to vary per material. All cleaning agents tested in this study appeared to inhibit the level of bacteria and fungi growth to acceptable levels for short duration tests. While several trends can be obtained from the current analysis, a series of test improvements are

  2. Numerical Studies of Magnetohydrodynamic Activity Resulting from Inductive Transients Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Sovinec, Carl R.

    2005-08-29

    This report describes results from numerical studies of transients in magnetically confined plasmas. The work has been performed by University of Wisconsin graduate students James Reynolds and Giovanni Cone and by the Principal Investigator through support from contract DE-FG02-02ER54687, a Junior Faculty in Plasma Science award from the DOE Office of Science. Results from the computations have added significantly to our knowledge of magnetized plasma relaxation in the reversed-field pinch (RFP) and spheromak. In particular, they have distinguished relaxation activity expected in sustained configurations from transient effects that can persist over a significant fraction of the plasma discharge. We have also developed the numerical capability for studying electrostatic current injection in the spherical torus (ST). These configurations are being investigated as plasma confinement schemes in the international effort to achieve controlled thermonuclear fusion for environmentally benign energy production. Our numerical computations have been performed with the NIMROD code (http://nimrodteam.org) using local computing resources and massively parallel computing hardware at the National Energy Research Scientific Computing Center. Direct comparisons of simulation results for the spheromak with laboratory measurements verify the effectiveness of our numerical approach. The comparisons have been published in refereed journal articles by this group and by collaborators at Lawrence Livermore National Laboratory (see Section 4). In addition to the technical products, this grant has supported the graduate education of the two participating students for three years.

  3. Poinsettia protoplasts - a simple, robust and efficient system for transient gene expression studies

    Directory of Open Access Journals (Sweden)

    Pitzschke Andrea

    2012-05-01

    Full Text Available Abstract Background Transient gene expression systems are indispensable tools in molecular biology. Yet, their routine application is limited to few plant species often requiring substantial equipment and facilities. High chloroplast and chlorophyll content may further impede downstream applications of transformed cells from green plant tissue. Results Here, we describe a fast and simple technique for the high-yield isolation and efficient transformation (>70% of mesophyll-derived protoplasts from red leaves of the perennial plant Poinsettia (Euphorbia pulccherrima. In this method no particular growth facilities or expensive equipments are needed. Poinsettia protoplasts display an astonishing robustness and can be employed in a variety of commonly-used downstream applications, such as subcellular localisation (multi-colour fluorescence or promoter activity studies. Due to low abundance of chloroplasts or chromoplasts, problems encountered in other mesophyll-derived protoplast systems (particularly autofluorescence are alleviated. Furthermore, the transgene expression is detectable within 90 minutes of transformation and lasts for several days. Conclusions The simplicity of the isolation and transformation procedure renders Poinsettia protoplasts an attractive system for transient gene expression experiments, including multi-colour fluorescence, subcellular localisation and promoter activity studies. In addition, they offer hitherto unknown possibilities for anthocyan research and industrial applications.

  4. Femtosecond Heterodyne Transient Grating Spectroscopic Studies of Intramolecular Charge Transfer Character of Peridinin and Peridinin Analogs

    Science.gov (United States)

    Bishop, Michael; Khosravi, Soroush; Obaid, Razib; Whitelock, Hope; Carroll, Ann Marie; Lafountain, Amy; Frank, Harry; Beck, Warren; Gibson, George; Berrah, Nora

    2016-05-01

    The peridinin chlorophyll-a protein is a light harvesting complex found in several species of dinoflagellates. Peridinin absorbs strongly in the mid-visible spectral region and, despite the lack of a strong permanent dipole moment in its lowest energy excited state, is able to transfer excitation energy quickly and efficiently to chlorophyll-a. It is believed that the high efficiency arises from the development of intramolecular charge-transfer (ICT) character upon photoexcitation. Recently, heterodyne transient grating spectroscopy has been used to study the ultrafast (<50 fs) dynamics of β carotene and peridinin. The studies show evidence for a structurally displaced intermediate in both cases and strong ICT character in the case of peridinin, but up to now the work has not provided appropriate control experiments. The present experiments examine peridinin and two peridinin analogs, S1-peridinin and S2-peridinin. S1-peridinin is reported to have greatly diminished ICT character, and S2-peridinin is reported to have little-or-no ICT character. Heterodyne transient grating data will be presented and provide a more unambiguous characterization spectral and kinetic properties associated with the peridinin ICT state. Funded by the DoE-BES, Grant No. DE-SC0012376.

  5. Progress in preliminary studies at Ottana Solar Facility

    Science.gov (United States)

    Demontis, V.; Camerada, M.; Cau, G.; Cocco, D.; Damiano, A.; Melis, T.; Musio, M.

    2016-05-01

    The fast increasing share of distributed generation from non-programmable renewable energy sources, such as the strong penetration of photovoltaic technology in the distribution networks, has generated several problems for the management and security of the whole power grid. In order to meet the challenge of a significant share of solar energy in the electricity mix, several actions aimed at increasing the grid flexibility and its hosting capacity, as well as at improving the generation programmability, need to be investigated. This paper focuses on the ongoing preliminary studies at the Ottana Solar Facility, a new experimental power plant located in Sardinia (Italy) currently under construction, which will offer the possibility to progress in the study of solar plants integration in the power grid. The facility integrates a concentrating solar power (CSP) plant, including a thermal energy storage system and an organic Rankine cycle (ORC) unit, with a concentrating photovoltaic (CPV) plant and an electrical energy storage system. The facility has the main goal to assess in real operating conditions the small scale concentrating solar power technology and to study the integration of the two technologies and the storage systems to produce programmable and controllable power profiles. A model for the CSP plant yield was developed to assess different operational strategies that significantly influence the plant yearly yield and its global economic effectiveness. In particular, precise assumptions for the ORC module start-up operation behavior, based on discussions with the manufacturers and technical datasheets, will be described. Finally, the results of the analysis of the: "solar driven", "weather forecasts" and "combined storage state of charge (SOC)/ weather forecasts" operational strategies will be presented.

  6. A preliminary magnetic study of Sawa lake sediments, Southern Iraq

    Science.gov (United States)

    Ameen, Nawrass

    2016-04-01

    A preliminary magnetic study combined with chemical analyses was carried out in Sawa Lake in Al-Muthanna province, southern Iraq, about 22 km south west of Samawa city (31°18'48.80"N, 45°0'25.25"E). The lake is about 4.74 km length, 1.75 km width and 5.5 m height, it is surrounded by a salt rim which is higher than the lake water by about 2.8 m and sea water by about 18.5 m (Naqash et al., 1977 in Hassan, 2007). The lake is an elongated closed basin with no surface water available to it, it may be fed by groundwater of the Euphrates and Dammam aquifers through system of joints and cracks. This study aims to investigate the concentrations of selected heavy metals as pollutants and magnetic susceptibility (MS) and other magnetic properties of sediment samples from fifty sites collected from the bottom of the lake, the study area lies in an industrial area. The results show spatial variations of MS with mean value of about 4.58 x 10-8 m3 kg-1. Scanning electron microscopy and magnetic mineralogy parameters indicate the dominance of soft magnetic phase like magnetite and presence of hard magnetic phase like hematite. Spatial variations of MS combined with the concentrations of heavy metals suggests the efficiency of magnetic methods as effective, inexpensive and non-time consuming method to outlining the heavy metal pollution. References: Hassan W.F., 2007. The Physio-chemical characteristic of Sawa lake water in Samawa city-Iraq. Marine Mesopotamica, 22(2), 167-179.

  7. Detection of fast radio transients with multiple stations: a case study using the Very Long Baseline Array

    CERN Document Server

    Thompson, David R; Brisken, Walter; Deller, Adam T; Majid, Walid A; Tingay, Steven J; Wayth, Randall B

    2011-01-01

    Recent investigations reveal an important new class of transient radio phenomena that occur on sub-millisecond timescales. Often transient surveys' data volumes are too large to archive exhaustively. Instead, an on-line automatic system must excise impulsive interference and detect candidate events in real-time. This work presents a case study using data from multiple geographically distributed stations to perform simultaneous interference excision and transient detection. We present several algorithms that incorporate dedispersed data from multiple sites, and report experiments with a commensal real-time transient detection system on the Very Long Baseline Array (VLBA). We test the system using observations of pulsar B0329+54. The multiple-station algorithms enhanced sensitivity for detection of individual pulses. These strategies could improve detection performance for a future generation of geographically distributed arrays such as the Australian Square Kilometre Array Pathfinder and the Square Kilometre A...

  8. Resting state brain dynamics and its transients: a combined TMS-EEG study

    Science.gov (United States)

    Bonnard, Mireille; Chen, Sophie; Gaychet, Jérôme; Carrere, Marcel; Woodman, Marmaduke; Giusiano, Bernard; Jirsa, Viktor

    2016-01-01

    The brain at rest exhibits a spatio-temporally rich dynamics which adheres to systematic behaviours that persist in task paradigms but appear altered in disease. Despite this hypothesis, many rest state paradigms do not act directly upon the rest state and therefore cannot confirm hypotheses about its mechanisms. To address this challenge, we combined transcranial magnetic stimulation (TMS) and electroencephalography (EEG) to study brain’s relaxation toward rest following a transient perturbation. Specifically, TMS targeted either the medial prefrontal cortex (MPFC), i.e. part of the Default Mode Network (DMN) or the superior parietal lobule (SPL), involved in the Dorsal Attention Network. TMS was triggered by a given brain state, namely an increase in occipital alpha rhythm power. Following the initial TMS-Evoked Potential, TMS at MPFC enhances the induced occipital alpha rhythm, called Event Related Synchronisation, with a longer transient lifetime than TMS at SPL, and a higher amplitude. Our findings show a strong coupling between MPFC and the occipital alpha power. Although the rest state is organized around a core of resting state networks, the DMN functionally takes a special role among these resting state networks. PMID:27488504

  9. Experimental study of frost heaving force based on transient shock response using piezoceramic sensors

    Science.gov (United States)

    Wang, Ruolin; Peng, Tongxiao; Wang, Ming L.

    2016-04-01

    In seasonally frozen soil regions, the frost heaving problem made it difficult to monitor or evaluate the pile safety for long term. So far, no mature tool can be utilized to monitor the frost heaving force, which was unevenly distributed along the pile. In this paper, a piezoceramic sensing based transient excitation response approach was proposed to monitor the frost heaving force in real time. Freeze-thaw cycles can result in great changes of soil engineering properties, including the frost heaving force. So, the freeze-thaw cycle was repeated fourth to study its effect. In the experiment, transient horizontal shock on the top of the pile will be detected by the 6 PZT sensors glued on the pile. The signal data received by the 6 PZT sensors can be used to illustrate the frost heaving force distribution along the pile. Moisture content effect is also one of the important reasons that cause the variation of soil mechanical properties. So three different moisture content (6%, 12%, 18%) testing soil were used in this experiment to detect the variance of the frost heaving force. An energy indicator was developed to quantitatively evaluate the frost heaving force applied on the pile. The experimental results showed that the proposed method was effective in monitoring the uneven distribution of frost heaving force along the pile.

  10. Femtosecond Transient Absorption Studies in Cadmium Selenide Nanocrystal Thin Films Prepared by Chemical Bath Deposition Method

    Directory of Open Access Journals (Sweden)

    M. C. Rath

    2007-01-01

    Full Text Available Dynamics of photo-excited carrier relaxation processes in cadmium selenide nanocrystal thin films prepared by chemical bath deposition method have been studied by nondegenerate femtosecond transient pump-probe spectroscopy. The carriers were generated by exciting at 400 nm laser light and monitored by several other wavelengths. The induced absorption followed by a fast bleach recovery observed near and above the bandgap indicates that the photo-excited carriers (electrons are first trapped by the available traps and then the trapped electrons absorb the probe light to show a delayed absorption process. The transient decay kinetics was found to be multiexponential in nature. The short time constant, <1 picosecond, was attributed to the trapping of electrons by the surface and/or deep traps and the long time constant, ≥20 picoseconds, was due to the recombination of the trapped carriers. A very little difference in the relaxation processes was observed in the samples prepared at bath temperatures from 25∘C to 60∘C.

  11. Resting state brain dynamics and its transients: a combined TMS-EEG study.

    Science.gov (United States)

    Bonnard, Mireille; Chen, Sophie; Gaychet, Jérôme; Carrere, Marcel; Woodman, Marmaduke; Giusiano, Bernard; Jirsa, Viktor

    2016-08-04

    The brain at rest exhibits a spatio-temporally rich dynamics which adheres to systematic behaviours that persist in task paradigms but appear altered in disease. Despite this hypothesis, many rest state paradigms do not act directly upon the rest state and therefore cannot confirm hypotheses about its mechanisms. To address this challenge, we combined transcranial magnetic stimulation (TMS) and electroencephalography (EEG) to study brain's relaxation toward rest following a transient perturbation. Specifically, TMS targeted either the medial prefrontal cortex (MPFC), i.e. part of the Default Mode Network (DMN) or the superior parietal lobule (SPL), involved in the Dorsal Attention Network. TMS was triggered by a given brain state, namely an increase in occipital alpha rhythm power. Following the initial TMS-Evoked Potential, TMS at MPFC enhances the induced occipital alpha rhythm, called Event Related Synchronisation, with a longer transient lifetime than TMS at SPL, and a higher amplitude. Our findings show a strong coupling between MPFC and the occipital alpha power. Although the rest state is organized around a core of resting state networks, the DMN functionally takes a special role among these resting state networks.

  12. A Preliminary Feasibility Study On Seismic Monitoring Of Polymer Flooding

    Science.gov (United States)

    Nguyen, P. K.; Park, C.; Lim, B.; Nam, M.

    2012-12-01

    Polymer flooding using water with soluble polymers is an enhanced oil recovery technique, which intends to maximize oil-recovery sweep efficiency by minimizing fingering effects and as a result creating a smooth flood front; polymer flooding decreases the flow rates within high permeability zone while enhances those of lower permeabilities. Understanding of fluid fronts and saturations is critical to not only optimizing polymer flooding but also monitoring the efficiency. Polymer flooding monitoring can be made in single well scale with high-resolution wireline logging, in inter-well scale with tomography, and in reservoir scale with surface survey. For reservoir scale monitoring, this study makes a preliminary feasibility study based on constructing rock physics models (RPMs), which can bridge variations in reservoir parameters to the changes in seismic responses. For constructing RPMs, we change reservoir parameters with consideration of polymer flooding to a reservoir. Time-lapse seismic data for corresponding RPMs are simulated using a time-domain staggered-finite-difference modeling with implementation of a boundary condition of conventional perfect match layer. Analysis on time-lapse seismic data with respect to the changes in fluid front and saturation can give an insight on feasibility of surface seismic survey to polymer flooding. Acknowledgements: This work was supported by the Energy Efficiency & Resources of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) grant funded by the Korea government Ministry of Knowledge Economy (No. 2012T100201588). Myung Jin Nam was partially supported by the National Research Foundation of Korea(NRF) grant funded by the Korea government(MEST) (No. 2011-0014684).

  13. Nevada potential repository preliminary transportation strategy: Study 1

    Energy Technology Data Exchange (ETDEWEB)

    None,

    1995-04-01

    Limited feasible options exist when considering the shipment of spent nuclear fuel and high-level radioactive waste. These options are rail or truck; because of the weight associated with transportation casks (68.0 to 113.4 tonnes/75 to 125 tons), heavy-haul trucks are also considered. Yucca Mountain currently lacks rail service or an existing right-of-way for rail; it also lacks a dedicated highway suitable for heavy-haul trucks. Approximately 11,230 shipments by rail are planned from waste producer sites to Nevada, with an additional 1,041 shipments by legal-weight truck from four reactor sites not capable of upgrading for rail shipment. This study identifies the reasonable alternatives for waste transport to the potential repository site, describes the evaluation process performed to identify those alternatives, and discusses the reasons for elimination of transportation routes deemed to be not reasonable. The study concluded that heavy haul truck transportation is feasible-cost is very favorable when compared to rail-but route restrictions must be further evaluated. In addition to restrictions due to seasonal weather conditions, specific routes have additional restrictions, including no travel on holidays or weekends, and travel during daylight hours only. Further restrictions will be imposed by the U.S. Department of Transportation based on routing of radioactive materials by highway. Operation and maintenance costs for heavy-haul over a 24-year period, based on preliminary information, were calculated on an estimated operational cost of $15,000 per trip, with an estimated 468 trips per year average (11,230 total trips), for an estimated cost of $171 million to $173 million, depending on the route used. Because the initial costs and the total system life cycle costs of heavy-haul are approximately 50 percent lower than the lowest rail cost, this option will continue to be evaluated.

  14. Usefulness of texture analysis in differentiating transient from persistent part-solid nodules(PSNs: a retrospective study.

    Directory of Open Access Journals (Sweden)

    Sang Hwan Lee

    Full Text Available BACKGROUND: Early discrimination between transient and persistent par-solid ground-glass nodules (PSNs at CT is essential for patient management. The objective of our study was to retrospectively investigate the value of texture analysis in differentiating pulmonary transient and persistent PSNs in addition to clinical and CT features. METHODS: This retrospective study was performed with IRB approval and a waiver of the requirement for patients' informed consent. From January 2007 to October 2009, we identified 77 individuals (39 men and 38 women; mean age, 55 years with 86 PSNs on thin-section chest CT. Thirty-nine PSNs in 31 individuals were transient and 47 PSNs in 46 patients were persistent. The clinical, CT, and texture features of PSNs were evaluated. To investigate the additional value of texture analysis in differentiating transient from persistent PSNs, logistic regression analysis and C-statistics were performed. RESULTS: Between transient and persistent PSNs, there were significant differences in age, gender, smoking history, and eosinophil count among the clinical features. As for thin-section CT features, there were significant differences in lesion size, solid portion size, and lesion multiplicity. In terms of texture features, there were significant differences in mean attenuation, skewness of whole PSN, attenuation ratio of whole PSN to inner solid portion, and 5-, 10-, 25-, 50-percentile CT numbers of whole PSN. Multivariate analysis revealed eosinophilia, lesion size, lesion multiplicity, mean attenuation of whole PSN, skewness of whole PSN, and 5-percentile CT number were significant independent predictors of transient PSNs. (P<0.05 C-statistics revealed that texture analysis incorporating clinical and CT features (AUC, 92.9% showed significantly higher differentiating performance of transient from persistent PSNs compared with the clinical and CT features alone (AUC, 79.0%. (P =  0.004. CONCLUSION: Texture analysis of

  15. Study of Deep Carbonate Reservoirs in the Desert Areas by Transient Electromagnetic Method

    Institute of Scientific and Technical Information of China (English)

    HeZhanxiang; LiuZebin; SongQunhui; gangXianghao; LuJiangnan

    2003-01-01

    In 1997, the TZ- 162 well in Tazhong area of the Tarim basin hit the lower Paleozoic dolomite reservoir at a depth of 5,900 m. The distribution of the dolomite reservoir, however,was very difficult to delineate due to the complex surface conditions and poor seismic properties. High-precision transient electromagnetic sounding (TEM) was conducted and good results obtained in this area. This paper discussed the principle,data processing and interpretation of this method. The resultsof studying the dolomite reservoirs demonstrated the effectiveness of the method in studying the low-resistance dolomite reservoirs in the high-resistance carbonates. This method should be an effective one to study reservoirs in areas with similar physical properties as well.

  16. A Preliminary Study on Cathodic Prevention in Reinforced Mortar

    NARCIS (Netherlands)

    Koleva, D.A.; Van Breugel, K.; Mol, J.M.C.; De Wit, J.H.W.

    2010-01-01

    This work presents the preliminary tests on the performance of cathodic prevention (CPre) in reinforced mortar, subjected to aggressive (10% NaCl environment). Cathodic prevention is an electrochemical technique for minimizing, actually "preventing" any eventual corrosion of the steel bars in reinfo

  17. Technology User Groups and Early Childhood Education: A Preliminary Study

    Science.gov (United States)

    Parette, Howard P.; Hourcade, Jack J.; Blum, Craig; Watts, Emily H.; Stoner, Julia B.; Wojcik, Brian W.; Chrismore, Shannon B.

    2013-01-01

    This article presents a preliminary examination of the potential of Technology User Groups as a professional development venue for early childhood education professionals in developing operational and functional competence in using hardware and software components of a Technology toolkit. Technology user groups are composed of varying numbers of…

  18. Orofacial Muscle Activity of Children Who Stutter: A Preliminary Study.

    Science.gov (United States)

    Kelly, Ellen M.; And Others

    1995-01-01

    This preliminary investigation of stuttering development and maturation of speech motor processes recorded the electromyographic activity of the orofacial muscles of nine children who stuttered. Results suggest that the emergence of tremor-like instabilities in the speech motor processes of stuttering children may coincide with aspects of general…

  19. Orofacial Muscle Activity of Children Who Stutter: A Preliminary Study.

    Science.gov (United States)

    Kelly, Ellen M.; And Others

    1995-01-01

    This preliminary investigation of stuttering development and maturation of speech motor processes recorded the electromyographic activity of the orofacial muscles of nine children who stuttered. Results suggest that the emergence of tremor-like instabilities in the speech motor processes of stuttering children may coincide with aspects of general…

  20. Finite element modelling of the tricuspid valve: A preliminary study.

    Science.gov (United States)

    Stevanella, Marco; Votta, Emiliano; Lemma, Massimo; Antona, Carlo; Redaelli, Alberto

    2010-12-01

    The incomplete efficacy of current surgical repair procedures of the tricuspid valve (TV) demands a deeper comprehension of the physiological TV biomechanics. To this purpose, computational models can provide quantitative insight into TV biomechanical response and allow analysing the role of each TV substructure. We present here a three-dimensional finite element model of the tricuspid valve that takes into account most of its peculiar features. Experimental measurements were performed on human and porcine valves to obtain a more detailed TV anatomical framework. To overcome the complete lack of information on leaflets mechanical properties, we performed a sensitivity analysis on the parameters of the adopted non-linear hyperelastic constitutive model, hypothesizing three different parameter sets for three significant collagen fibre distributions. Results showed that leaflets' motion and maximum principal stress distribution were almost insensitive to the different material parameters considered. Highest stresses (about 100kPa) were located near the annulus of the anterior and septal leaflets, while the posterior leaflet experienced lower stresses (about 55kPa); stresses at the commissures were nearly zero. Conversely, changes in constitutive parameters deeply affected leaflets' strains magnitude, but not their overall pattern. Strains computed assuming that TV leaflets tissue are reinforced by a sparse and loosely arranged network of collagen fibres fitted best experimental data, thus suggesting that this may be the actual microstructure of TV leaflets. In a long-term perspective, this preliminary study aims at providing a starting point for the development of a predictive tool to quantitatively evaluate TV diseases and surgical repair procedures.

  1. [Study on relations between transient receptor potential vanilloid 1 and pungent property of traditional Chinese medicines].

    Science.gov (United States)

    Wang, Xing; Zhang, Yan-Ling; Wang, Yun; Ren, Zhen-Zhen; Bao, Hong-Juan; Qiao, Yan-Jiang

    2014-07-01

    The five-flavor theory of traditional Chinese medicines (TCM) and the flavor efficacy generation mechanism has long been focuses and difficulties in studies on traditional Chinese medicinal properties. In this paper, by using the pharmacophore-based virtual screening technique, the authors discussed the relations between the pungent property and transient receptor potential vanilloid 1 (TRPV1) by studying the TCM components' role in regulating TRPV1 ion channel. The results showed that the matching relationship between TRPV1 agonist pharmacophore model and TCM chemical components could identify the active ingredients from pungent herbs. Therefore, the authors proposed that TRPV1 is one of the potential targets for efficient pungent herbs. The pungent property of TCMs is decided by its chemical components, and consistent with the inherited and additive characteristics.

  2. Simulation and Test Study on Very Fast Transient Overvoltage in 1000kV GIS Substation

    Science.gov (United States)

    Han, Bin; Lin, Jiming; Ban, Liangeng; Wang, Hao; Li, Zhibing; Xiang, Zutao

    2017-05-01

    Disconnector switching in gas insulated switchgear (GIS) generates very fast transient overvoltage (VFTO). VFTO may damage the insulation of GIS equipment. This paper studies the VFTO of a 1000kV GIS substation. The simulation models are obtained according to the configuration of GIS. Operation modes of disconnector were summarized. The characteristics of VFTO were obtained. During the system commissioning test of the substation, VFTO were measured during disconnector switching. Comparison was made between the test and simulation results. The simulation results were in agreement with the test results. The accuracy of the simulation model is verified. Simulation and test study shows that it is safe to do switching operation of disconnector in this GIS substation without damping resistor.

  3. Adsorption of Roxarsone onto Drinking Water Treatment Residuals: Preliminary Studies

    Science.gov (United States)

    Salazar, J.; Sarkar, D.; Datta, R.; Sharma, S.

    2006-05-01

    above parameters were varied one at a time to study their effects on roxarsone adsorption. Desorption studies were carried out using 125 mg/L phosphorous at predetermined interval of time. In addition to analyzing for total As by an ICP-MS, aqueous speciation of As was performed using a coupled HPLC-ICP-MS system. Preliminary studies show significant roxarsone adsorption capacity of the WTRs.

  4. Preliminary study for small animal preclinical hadrontherapy facility

    Science.gov (United States)

    Russo, G.; Pisciotta, P.; Cirrone, G. A. P.; Romano, F.; Cammarata, F.; Marchese, V.; Forte, G. I.; Lamia, D.; Minafra, L.; Bravatá, V.; Acquaviva, R.; Gilardi, M. C.; Cuttone, G.

    2017-02-01

    Aim of this work is the study of the preliminary steps to perform a particle treatment of cancer cells inoculated in small animals and to realize a preclinical hadrontherapy facility. A well-defined dosimetric protocol was developed to explicate the steps needed in order to perform a precise proton irradiation in small animals and achieve a highly conformal dose into the target. A precise homemade positioning and holding system for small animals was designed and developed at INFN-LNS in Catania (Italy), where an accurate Monte Carlo simulation was developed, using Geant4 code to simulate the treatment in order to choose the best animal position and perform accurately all the necessary dosimetric evaluations. The Geant4 application can also be used to realize dosimetric studies and its peculiarity consists in the possibility to introduce the real target composition in the simulation using the DICOM micro-CT image. This application was fully validated comparing the results with the experimental measurements. The latter ones were performed at the CATANA (Centro di AdroTerapia e Applicazioni Nucleari Avanzate) facility at INFN-LNS by irradiating both PMMA and water solid phantom. Dosimetric measurements were performed using previously calibrated EBT3 Gafchromic films as a detector and the results were compared with the Geant4 simulation ones. In particular, two different types of dosimetric studies were performed: the first one involved irradiation of a phantom made up of water solid slabs where a layer of EBT3 was alternated with two different slabs in a sandwich configuration, in order to validate the dosimetric distribution. The second one involved irradiation of a PMMA phantom made up of a half hemisphere and some PMMA slabs in order to simulate a subcutaneous tumour configuration, normally used in preclinical studies. In order to evaluate the accordance between experimental and simulation results, two different statistical tests were made: Kolmogorov test and

  5. Grasslands contaminant study selenium in algae and wintering and resident waterfowl and waterbirds : preliminary summary

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — A preliminary summary of a study of contaminants in waterbirds and in the western grasslands of Merced County. The purpose of this study was two-fold: 1) to...

  6. Studies of solvent effects on reaction dynamics using ultrafast transient absorption spectroscopy

    Science.gov (United States)

    Harris, Don Ahmasi

    Ultrafast transient absorption spectroscopy was used to investigate the solvent dependent reaction dynamics of two prototypical chemical systems: (1) The ring-opening reaction of 1,3-cyclohexadiene, the isolated chromophore in Provitamin D, and (2) The photolysis of various Vitamin B12 cofactors. We investigated the influence of solvent polarity on the ground state conformational relaxation of 1,3,5-cis hexatriene subsequent to the ring opening of 1,3-cyclohexadiene in methanol and 1-propanol solvents. Comparisons to the conformational relaxation in alkane solvents studied earlier demonstrated a surprising influence of solvent polarity on single bond isomerization. Temperature dependent transient absorption measurements were performed on 1,3,5-cis hexatriene in cyclohexane and 1-propanol to determine the effect of solvent polarity on the activation energy barrier for ground state single bond isomerization. These measurements conclude that the polar solvent lowers the energy barrier for single bond isomerization allowing conformational relaxation to proceed faster in alcohol solvents compared to alkane solvents. With no perceived polar transition state for single bond isomerization, this result disagrees with the conventional view of solvation and differentiates the single bond isomerization dynamics of polyenes from alkanes. Transient absorption spectroscopy was also utilized to study the solvent effects in the photolysis of various B12 cofactors in different environments. We investigated the solvent dependent photolysis of adenosylcobalamin, methylcobalamin, and cyanocobalamin in water and ethylene glycol as a function of solvent temperature. In comparing the radical cage escape of adenosylcobalamin and cyanocobalamin, we determined a larger than expected hydrodynamic radii for the diffusing radicals in water compared to ethylene glycol, thus making necessary a revised perspective of solvent interaction with the diffusing radical. In addition, we investigated the

  7. [Peritoneal equilibration test: Conventional versus adapted. Preliminary study].

    Science.gov (United States)

    Zaloszyc, Ariane; Schmitt, Claus Peter; Schaefer, Betti; Doutey, Armelle; Terzic, Joëlle; Menouer, Soraya; Higel, Laetitia; Fischbach, Michel

    2017-02-01

    Conventional automated peritoneal dialysis (APD) is prescribed as a repetition of cycles with the same dwell time and the same fill volume. Water and sodium balance remains a common problem among patients on peritoneal dialysis. More recently, adapted automated peritoneal dialysis was described, as a combination of short dwells with a low volume, in order to enhance ultrafiltration, followed by long dwells with a large fill volume to favor solute removal. We performed a preliminary crossover study on 4 patients. The total amount of dialysate was the same, i.e. 2L/m(2) as well as the total duration of the test, i.e. 150 minutes. The conventional test was made with two identical cycles, each cycle had a fill volume of 1L/m(2) and a duration of 75 minutes, while the adapted test was performed with one short cycle, i.e. 30 minutes with a low fill volume, i.e. 0.6L/m(2), followed by a long cycle, i.e. 120 minutes, with a large fill volume, i.e. 1.4L/m(2). Sodium extraction was improved by 29.3mmol/m(2) (169%) in the adapted test in comparison to the conventional test. Ultrafiltration was enhanced by 159mL/m(2) (128%) in the adapted test compared to the conventional one. Glucose absorption was decreased by 35% in the adapted test in comparison to the conventional test and osmotic conductance was also improved. In conclusion, adapted dialysis may allow for a better volume and sodium balance, since we observed an improvement in sodium extraction and ultrafiltration. This pre-study authorizes an improvement of the European Pediatric Study's protocol on Adapted APD, already started and which will continue in the next months. Copyright © 2016 Association Société de néphrologie. Published by Elsevier SAS. All rights reserved.

  8. Transient state study of electric motor heating and phase change solid-liquid cooling

    Energy Technology Data Exchange (ETDEWEB)

    Bellettre, J.; Sartre, V.; Lallemand, A. [Centre National de la Recherche Scientifique (CNRS), Centre de Thermique de Lyon, Villeurbanne, 69 (France); Biais, F. [AUXILEC, Chatou, 78 (France)

    1997-01-01

    This study reports on modelling of an autosynchronous electric motor stator, operating at transient state. The developed model, of the modal type, includes around 20 nodes. The simulations showed that hot spots are localized on the winding heads and led to the choice of a solid-liquid phase change cooling system. The comparison between simulation and experiment permitted the identification of unknown parameters. The model gives a good accuracy during steady-state and in the rising temperature phase. The modelling of the phase change cooling is realized by the addition of two nodes. The sensitivity analysis to PCM properties shows that the hot spot temperature decreases with increasing conductivities, inertia and latent heat of melting of the PCM and with decreasing melting temperature. Gallium (metal melting at 30{sup o}C) is the best PCM for the cooling of hot spots and P116 paraffin is the best non-metallic PCM. (author)

  9. Western Wind and Solar Integration Study Phase 3 – Frequency Response and Transient Stability

    Energy Technology Data Exchange (ETDEWEB)

    Miller, N. W. [GE Energy Management, Schenectady, NY (United States); Shao, M. [GE Energy Management, Schenectady, NY (United States); Pajic, S. [GE Energy Management, Schenectady, NY (United States); D' Aquila, R. [GE Energy Management, Schenectady, NY (United States)

    2014-12-01

    Power system operators and utilities worldwide have concerns about the impact of high-penetration wind and solar generation on electric grid reliability (EirGrid 2011b, Hydro-Quebec 2006, ERCOT 2010). The stability of North American grids under these conditions is a particular concern and possible impediment to reaching future renewable energy goals. Phase 3 of the Western Wind and Solar Integration Study (WWSIS-3) considers a 33% wind and solar annual energy penetration level that results in substantial changes to the characteristics of the bulk power system, including different power flow patterns, different commitment and dispatch of existing synchronous generation, and different dynamic behavior of wind and solar generation. WWSIS-3 evaluates two specific aspects of fundamental frequency system stability: frequency response and transient stability.

  10. Detailed study of transient anomalous electric field vector focused by parabolic mirror

    Science.gov (United States)

    Shibata, Kazunori; Uemoto, Mitsuharu; Takai, Mayuko; Watanabe, Shinichi

    2017-03-01

    This paper provides a detailed theoretical analysis of the unexpected transient divergent and rotational distributions of the focused electric field vector reported in Shibata et al (2015 Phys. Rev. A 92 053806). We reveal the physical origin of these distributions. More quantitatively, we derive the semi-analytic expressions and clarify how these distributions depend on the mirror size, offset angle, and the intensity distribution of the incident parallel light. We compare the formulas with numerical calculations and evaluate the area where linearity holds. If the wavelength and the mirror size are sufficiently shorter than the focal length, the radius of the linear area becomes longer than the wavelength. These formulas and evaluations are useful for studies, which require high spatio-temporal resolution.

  11. Preliminary experimental study of a carbon fiber array cathode

    Science.gov (United States)

    Li, An-kun; Fan, Yu-wei

    2016-08-01

    The preliminary experimental results of a carbon fiber array cathode for the magnetically insulated transmission line oscillator (MILO) operations are reported. When the diode voltage and diode current were 480 kV and 44 kA, respectively, high-power microwaves with a peak power of about 3 GW and a pulse duration of about 60 ns were obtained in a MILO device with the carbon fiber array cathode. The preliminary experimental results show that the shot-to-shot reproducibility of the diode current and the microwave power is stable until 700 shots. No obvious damage or deterioration can be observed in the carbon fiber surface morphology after 700 shots. Moreover, the cathode performance has no observable deterioration after 700 shots. In conclusion, the maintain-free lifetime of the carbon fiber array cathode is more than 700 shots. In this way, this carbon fiber array cathode offers a potential replacement for the existing velvet cathode.

  12. Preliminary Studies on Pulsed Electric Field Breakdown of Lead Azide

    Science.gov (United States)

    1976-10-01

    1/2 OS CO ton NO. S3L TECHNICAL REPORT 4991 PRELIMINARY SUJDfES ON PULSED ELECTRIC FIELD BREAKDOWN OF LEAD AZIDE L AVRAMI M. BUMS D. DOWNS...Introduction Background A. Contact Effects B. Pulsed Electric Field Measurements Experimental A. Contact Effects B. Pulsed Electric Fields Discussion...B. Pulsed Electric Field Measurements The application of pulsed electric fields to lead azide does not exactly simulate the conditions experienced

  13. PRELIMINARY STUDY OF FISH CULTURE IN ABANDONED SAND MINING POOL

    Directory of Open Access Journals (Sweden)

    Bambang Gunadi

    2006-12-01

    Full Text Available One of main problems in freshwater aquaculture development in Indonesia, especially in Java, is unavailability of developing zone. It is important to find an underutilized area that meets for industrial scale freshwater aquaculture, i.e. sufficient water supply, wide area, and located in one area or zone. The abandoned mining (sand, tin, etc. pools distributed along the country might be the potential area for freshwater aquaculture business. For example, there are at least 13 water pools with total surface area of 250 ha at 15 km side of Citarum River in Karawang District (West Java Province. This study was conducted to obtain preliminary data about the prospect and potency of fish culture (tilapia, clariid catfish, and ‘patin’ catfish in abandoned sand-mining pools in Karawang District. Mini floating net cages of 1 x 1 x 1.5 m3 size were used for culturing fish, i.e. patin catfish (Pangasianodon hypophthalmus, nile tilapia (Oreochromis niloticus, and clariid catfish (Clarias gariepinus, separately. Patin catfish were stocked at a size of 2 g with a density of 300 fish per cage, tilapia were stocked at a size of 6 g with a density of 400 fish per cage, while  the clariid catfish were stocked at a size of 1.4 g with a density of 980 fish per cage. A floating commercial feed (30%—32% protein, 3%—5% fat was used at a daily rate of 9% biomass weight at the beginning and reduced gradually to 3% at the final culture period. Observed data showed that patin catfish grew from the initial size of 2.08 g to the final size 299.59 g in 5 months, nile tilapia grew from individual initial size of 5.92 g to the final size of 247.12 g in 14 weeks, and clariid catfish grew from initial size of 1.39 g to the final size of 73.10 g in 8 weeks. These three species were technically prospective for aquaculture development in the abandoned sand-mining pools.

  14. Single-molecule enzymology of steroid transforming enzymes: Transient kinetic studies and what they tell us.

    Science.gov (United States)

    Penning, Trevor M

    2016-07-01

    Structure-function studies on steroid transforming enzymes often use site-directed mutagenesis to inform mechanisms of catalysis and effects on steroid binding, and data are reported in terms of changes in steady state kinetic parameters kcat, Km and kcat/Km. However, this dissection of function is limited since kcat is governed by the rate-determining step and Km is a complex macroscopic kinetic constant. Often site-directed mutagenesis can lead to a change in the rate-determining step which cannot be revealed by just reporting a decrease in kcat alone. These issues are made more complex when it is considered that many steroid transforming enzymes have more than one substrate and product. We present the case for using transient-kinetics performed with stopped-flow spectrometry to assign rate constants to discrete steps in these multi-substrate reactions and their use to interpret enzyme mechanism and the effects of disease and engineered mutations. We demonstrate that fluorescence kinetic transients can be used to measure ligand binding that may be accompanied by isomerization steps, revealing the existence of new enzyme intermediates. We also demonstrate that single-turnover reactions can provide a klim for the chemical step and Ks for steroid-substrate binding and that when coupled with kinetic isotope effect measurements can provide information on transition state intermediates. We also demonstrate how multiple turnover experiments can provide evidence for either "burst-phase" kinetics, which can reveal a slow product release step, or linear-phase kinetics, in which the chemical step can be rate-determining. With these assignments it becomes more straightforward to analyze the effects of mutations. We use examples from the hydroxysteroid dehydrogenases (AKR1Cs) and human steroid 5β-reductase (AKR1D1) to illustrate the utility of the approach, which are members of the aldo-keto reductase (AKR) superfamily.

  15. Summary of the Preliminary Optical ICHMI Design Study: A Preliminary Engineering Design Study for a Standpipe Viewport

    Energy Technology Data Exchange (ETDEWEB)

    Anheier, Norman C.; Qiao, Hong (Amy); Berglin, Eric J.; Hatchell, Brian K.

    2013-12-26

    This summary report examines an in-vessel optical access concept intended to support standoff optical instrumentation, control and human-machine interface (ICHMI) systems for future advanced small modular reactor (AdvSMR) applications. Optical-based measurement and sensing systems for AdvSMR applications have several key benefits over traditional instrumentation and control systems used to monitor reactor process parameters, such as temperature, flow rate, pressure, and coolant chemistry (Anheier et al. 2013). Direct and continuous visualization of the in-vessel components can be maintained using external cameras. Many optical sensing techniques can be performed remotely using open optical beam path configurations. Not only are in-vessel cables eliminated by these configurations, but also sensitive optical monitoring components (e.g., electronics, lasers, detectors, and cameras) can be placed outside the reactor vessel in the instrument vault, containment building, or other locations where temperatures and radiation levels are much lower. However, the extreme AdvSMR environment present challenges for optical access designs and optical materials. Optical access is not provided in any commercial nuclear power plant or featured in any reactor design, although successful implementation of optical access has been demonstrated in test reactors (Arkani and Gharib 2009). This report outlines the key engineering considerations for an AdvSMR optical access concept. Strict American Society of Mechanical Engineers (ASME) construction codes must be followed for any U.S. nuclear facility component (ASME 2013); however, the scope of this study is to evaluate the preliminary engineering issues for this concept, rather than developing a nuclear-qualified design. In addition, this study does not consider accident design requirements. In-vessel optical access using a standpipe viewport concept serves as a test case to explore the engineering challenges and performance requirements

  16. Transient Analysis Used to Study Thermal Radiation Effects in Single and Composite Semitransparent Layers

    Science.gov (United States)

    1996-01-01

    In a continuing in-house program at the NASA Lewis Research Center, analytical and numerical methods are being developed to apply radiative analysis to predict transient temperature distributions and heat flows in partially transmitting materials. Results have been obtained for a single plane layer, and a transient analysis is being developed for a two-layer composite where each layer has a different refractive index. Because the ceramic refractive indices are larger than one, internal reflections are produced at the surfaces and at the internal interface. Reflections tend to distribute energy within a layer, and this affects the transient temperature distributions.

  17. Preliminary Safety Analysis of Anticipated Transient without Scram (ATWS) Events for the Prototype GEN-IV SFR (PGSFR) using MARS-LMR

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Chiwoong; Ha, Kwiseok [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    A safety analysis of ATWS for the recently designed Prototype GEN-IV Sodium Cooled Fast Reactor (PGSFR) was conducted. Unprotected Transient Over-Power (UTOP), Unprotected Loss OF Flow (ULOF), and Unprotected Loss Of Heat Sink (ULOHS) were selected as representative events for the ATWS. In an unprotected condition, the power in the core is only controlled by reactivity feedbacks, which are interacted with the thermal-hydraulic characteristics of the components in the plant. Heat is removed by the steam generator (SG) and decay heat removal system (DHRS). Therefore, the major objectives of the safety analysis of the ATWS events are to investigate the thermal hydraulic characteristics of the DHRS and the SG, the neutron kinetic characteristics of the reactivity feedback, and the interaction between the neutron kinetics, and the thermal-hydraulics during the events.

  18. Preliminary study of superconducting bulk magnets for Maglev

    Science.gov (United States)

    Fujimoto, Hiroyuki; Kamijo, Hiroki

    Recent development shows that melt-processed YBaCuO (Y123) or Rare Earth (RE)123 superconductors have a high Jc at 77 K and high magnetic field, leading to high field application as a superconducting quasi-permanent bulk magnet with the liquid nitrogen refrigeration. One of the promising applications is a superconducting magnet for the magnetically levitated (Maglev) train. We discuss a superconducting bulk magnet for the Maglev train in the aspect of a preliminary design of the bulk magnet and also processing for (L)REBaCuO bulk superconductors and their characteristic superconducting properties.

  19. A pilot study on transient ischemic stroke induced with endothelin-1 in the rhesus monkeys

    Science.gov (United States)

    Dai, PeiMin; Huang, Hui; Zhang, Lin; He, Jing; Zhao, XuDong; Yang, FuHan; Zhao, Ning; Yang, JianZhen; Ge, LongJiao; Lin, Yu; Yu, HuaLin; Wang, JianHong

    2017-01-01

    Endothelin-1 (ET-1), a vasoconstrictor, has recently been used to induce focal ischemia in rodents and marmoset monkeys. The rhesus monkey, however, has numerous advantages to the rodent and marmoset that make it a superior and irreplaceable animal model for studying stroke in the brain. In the present study, after mapping the preferred hand representation in two healthy male monkeys with intracortical micro-stimulation, ET-1 was microinjected into the contralateral motor cortex (M1) to its preferred hand. The monkeys had been trained in three manual dexterity tasks before the microinjection and were tested for these tasks following the ET-1 injection. Brain Magnetic Resonance Imaging scans were performed 1, 7, 14 and 28 days post ischemia. It was found that ET-1 impaired the manual dexterity of the monkeys in the vertical slot and rotating Brinkman board tasks 3–8 days after the injection. Brain imaging found that severe edema was present 7 days after the focal ischemia. This data suggest that ET-1 can induce transient ischemic stroke in rhesus monkey and that ET-1 induced focal ischemia in non-human primates is a potential model to study the mechanism of stroke and brain repair after stroke. PMID:28358140

  20. Sampling the Radio Transient Universe: Studies of Pulsars and the Search for Extraterrestrial Intelligence

    Science.gov (United States)

    Chennamangalam, Jayanth

    The transient radio universe is a relatively unexplored area of astronomy, offering a variety of phenomena, from solar and Jovian bursts, to flare stars, pulsars, and bursts of Galactic and potentially even cosmological origin. Among these, perhaps the most widely studied radio transients, pulsars are fast-spinning neutron stars that emit radio beams from their magnetic poles. In spite of over 40 years of research on pulsars, we have more questions than answers on these exotic compact objects, chief among them the nature of their emission mechanism. Nevertheless, the wealth of phenomena exhibited by pulsars make them one of the most useful astrophysical tools. With their high densities, pulsars are probes of the nature of ultra-dense matter. Characterized by their high timing stability, pulsars can be used to verify the predictions of general relativity, discover planets around them, study bodies in the solar system, and even serve as an interplanetary (and possibly some day, interstellar) navigation aid. Pulsars are also used to study the nature of the interstellar medium, much like a flashlight illuminating airborne dust in a dark room. Studies of pulsars in the Galactic center can help answer questions about the massive black hole in the region and the star formation history in its vicinity. Millisecond pulsars in globular clusters are long-lived tracers of their progenitors, low-mass X-ray binaries, and can be used to study the dynamical history of those clusters. Another source of interest in radio transient astronomy is the hitherto undetected engineered signal from extraterrestrial intelligence. The Search for Extraterrestrial Intelligence (SETI) is an ongoing attempt at discovering the presence of technological life elsewhere in the Galaxy. In this work, I present my forays into two aspects of the study of the radio transient universe---pulsars and SETI. Firstly, I describe my work on the luminosity function and population size of pulsars in the globular

  1. Device Optimization and Transient Electroluminescence Studies of Organic light Emitting Devices

    CERN Document Server

    Li Juan Zo

    2003-01-01

    Organic light emitting devices (OLEDs) are among the most promising for flat panel display technologies. They are light, bright, flexible, and cost effective. And while they are emerging in commercial product, their low power efficiency and long-term degradation are still challenging. The aim of this work was to investigate their device physics and improve their performance. Violet and blue OLEDs were studied. The devices were prepared by thermal vapor deposition in high vacuum. The combinatorial method was employed in device preparation. Both continuous wave and transient electroluminescence (EL) were studied. A new efficient and intense UV-violet light emitting device was developed. At a current density of 10 mA/cm sup 2 , the optimal radiance R could reach 0.38 mW/cm sup 2 , and the quantum efficiency was 1.25%. using the delayed EL technique, electron mobilities in DPVBi and CBP were determined to be approx 10 sup - sup 5 cm sup 2 /Vs and approx 10 sup - sup 4 cm sup 2 /Vs, respectively. Overshoot effects...

  2. A Preliminary Case Study for Rectenna Sites in Indonesia

    Science.gov (United States)

    Purwanto, Y.; Collins, P.

    2004-12-01

    Electricity power generation using alternative energy sources in Indonesia has become an important policy. Until now, the contribution from alternative energy sources (especially from renewable energy sources) is very small, only about 1% of the total energy supply. It is expected that in the next 10 years this contribution will be raised to 20%. The development of renewable energy sources is primarily performed in remote areas, that are poor in infrastructure facilities. This is considered to be a good policy since there are many such remote areas in Indonesia that need development programs. The existence of Solar Power Satellite system will open a new horizon in alternative energy supply, including Indonesia, because of its higher efficiency compared to conventional terrestrial solar cells, with almost no influence from either climate or solar position. Like other countries in the world, Indonesia, although one of the largest mineral energy producers in the world (i.e. oil, coal, and natural gas), still gives attention to energy diversification programs, including solar energy utilization. SPS, being based on solar energy, could be a good choice. The Indonesian archipelago consists of thousands of islands (more than 13,000) and is the equatorial country with the longest equatorial extent (more than 5000 km). This condition is very good for energy reception from the SPS 2000 pilot plant since the energy transmitting system (spacetenna) will orbit above the equator. Along the equator there could be placed more than four receiving stations (rectenna), especially in remote areas. Thus, it is very important to consider the involvement of Indonesia in SPS energy reception research. This paper describes a preliminary study of the development possibilities in SPS energy reception in Indonesia. To define the rectenna sites and physical development aspect, this study considers some major aspects: environmental, technical, social, and economic aspects. Environmental aspects

  3. Western Wind and Solar Integration Study Phase 3 -- Frequency Response and Transient Stability (Report and Executive Summary)

    Energy Technology Data Exchange (ETDEWEB)

    Miller, N. W.; Shao, M.; Pajic, S.; D' Aquila, R.

    2014-12-01

    The primary objectives of Phase 3 of the Western Wind and Solar Integration Study (WWSIS-3) were to examine the large-scale transient stability and frequency response of the Western Interconnection with high wind and solar penetration, and to identify means to mitigate any adverse performance impacts via transmission reinforcements, storage, advanced control capabilities, or other alternatives.

  4. Charge deep-level transient spectroscopy study of high-energy-electron-beam-irradiated hydrogenated amorphous silicon

    NARCIS (Netherlands)

    Klaver, A.; Nádaždy, V.; Zeman, M.; Swaaiij, R.A.C.M.M.

    2006-01-01

    We present a study of changes in the defect density of states in hydrogenated amorphous silicon (a-Si:H) due to high-energy electron irradiation using charged deep-level transient spectroscopy. It was found that defect states near the conduction band were removed, while in other band gap regions the

  5. Transient studies of an Integrated Gasification Combined Cycle (IGCC) plant with CO2 capture

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharyya, D.; Turton, R.; Zitney, S.

    2010-01-01

    targets and quality of the feed to other sections, wherever applicable, without violating the operating constraints, and without sacrificing the efficiency. However, it was found that the emission of acid gases may far exceed the environmental targets and the overshoot of some of the key variables may be unacceptable under transient operation while following the load. A number of operational strategies and control configurations is explored for achieving these stringent requirements. The transient response of the plant is also studied by perturbing a number of key inputs.

  6. Preliminary study on the RF tuning of CSNS DTL

    Science.gov (United States)

    Yin, Xue-Jun; Li, A.-Hong; Xiao, Yong-Chuang; Chen, Qiang; Liu, Hua-Chang; Gong, Ke-Yun; Fu, Shi-Nian

    2014-02-01

    In the R&D of the CSNS Drift Tube Linac (DTL), the first unit tank with 28 drift tubes has been developed. The axial accelerating field is ramped from 2.2 MV/m to 3.1 MV/m in this tank. The required field flatness is less than ±2% with the standard deviation of 1% for the beam dynamics; the field stability should be less than 1% for machine stable operation. After successful alignment, RF tuning was carried out focusing on the field profile measurement. Four slug tuners and eleven post couplers were applied in this procedure. The ramped field and required stability had been achieved by fine adjustment of the slug tuners and post couplers. In this paper, the preliminary tuning results are presented and discussed.

  7. Preliminary Study on the RF tuning of CSNS DTL

    CERN Document Server

    Yin, Xuejun; Xiao, Yongchuang; Chen, Qiang; Liu, Huachang; Gong, Keyun; Fu, Shinan

    2013-01-01

    In the R&D of the CSNS Drift Tube Linac (DTL), the first unit tank with 28 drift tubes has been developed. The axial accelerating field is ramped from 2.2MV/m to 3.1MV/m in this tank. The required field flatness is less than 2 % with the standard deviation of 1 % for the beam dynamics. And the field stability should be less than 1% for machine stable operation. After the successful alignment, the RF tuning was carried out focusing on the field profile measurement. Four slug tuners and 11 post couplers were applied in this procedure. The ramped filed and required stability had been achieved by fine adjustment of the slug tuners and post couplers. In this paper, the preliminary tuning results are presented and discussed.

  8. Preliminary experimental study of liquid lithium water interaction

    Energy Technology Data Exchange (ETDEWEB)

    You, X.M.; Tong, L.L.; Cao, X.W., E-mail: caoxuewu@sjtu.edu.cn

    2015-10-15

    Highlights: • Explosive reaction occurs when lithium temperature is over 300 °C. • The violence of liquid lithium water interaction increases with the initial temperature of liquid lithium. • The interaction is suppressed when the initial water temperature is above 70 °C. • Steam explosion is not ignorable in the risk assessment of liquid lithium water interaction. • Explosion strength of liquid lithium water interaction is evaluated by explosive yield. - Abstract: Liquid lithium is the best candidate for a material with low Z and low activation, and is one of the important choices for plasma facing materials in magnetic fusion devices. However, liquid lithium reacts violently with water under the conditions of loss of coolant accidents. The release of large heats and hydrogen could result in the dramatic increase of temperature and pressure. The lithium–water explosion has large effect on the safety of fusion devices, which is an important content for the safety assessment of fusion devices. As a preliminary investigation of liquid lithium water interaction, the test facility has been built and experiments have been conducted under different conditions. The initial temperature of lithium droplet ranged from 200 °C to 600 °C and water temperature was varied between 20 °C and 90 °C. Lithium droplets were released into the test section with excess water. The shape of lithium droplet and steam generated around the lithium were observed by the high speed camera. At the same time, the pressure and temperature in the test section were recorded during the violent interactions. The preliminary experimental results indicate that the initial temperature of lithium and water has an effect on the violence of liquid lithium water interaction.

  9. Electronic relaxation dynamics of PCDA-PDA studied by transient absorption spectroscopy.

    Science.gov (United States)

    Joung, Joonyoung F; Baek, Junwoo; Kim, Youngseo; Lee, Songyi; Kim, Myung Hwa; Yoon, Juyoung; Park, Sungnam

    2016-08-17

    Photo-curable polymers originating from 10,12-pentacosadiynoic acid (PCDA-PDA) are commonly used polydiacetylenes (PDAs). PCDA-PDA exhibits thermochromic properties undergoing a unique colorimetric transition from blue to red as the temperature is increased from low to high. In this work, we have carefully studied the temperature-dependent optical properties of PCDA-PDA by using UV-visible absorption, FTIR, Raman, and transient absorption (TA) spectroscopy in combination with quantum chemical calculations. Temperature-dependent UV-visible absorption spectra indicate that PCDA-PDA exhibits reversible thermochromic properties up to 60 °C and its thermochromic properties become irreversible above 60 °C. Such distinct thermochromic properties are also manifested in TA signals so that the electronically excited PCDA-PDA relaxes to the ground state via an intermediate state at 20 °C (blue form) but it relaxes directly back to the ground state at 80 °C (red form). The electronic relaxation dynamics of PCDA-PDA are comprehensively analyzed based on different kinetic models by using the global fitting analysis method. The intermediate state in the blue form of PCDA-PDA is clearly found to be responsible for fluorescence quenching. FTIR and Raman spectroscopy and quantum chemical calculations confirm that the H-bonds between the carboxylic acid groups in PCDA-PDA are broken at high temperatures leading to an irreversible structural change of PCDA-PDA.

  10. Study of transient luminescence of three kinds of Ru complexes bound to DNA

    Institute of Scientific and Technical Information of China (English)

    ZHU WeiLing; LIU XueWen; WANG Hui; YU HuiJuan; LI AiZheng; CHAO Hui; ZHENG KangCheng; JI LiangNian

    2008-01-01

    The transient luminescence of three kinds of ruthenium complexes [Ru(bpy)2(7-CH3-dppz)]2+, [Ru(bpy)2(7-F-dppz)]2+ and [Ru(phen)2(7-F-dppz)]2+ bound to calf thy-mus DNA (ctDNA) has been studied by using the time-resolved spectroscopy. The results show that the luminescence is due to the radiative decay from the charge-transfer states to the ground state. By the Interaction with DNA, the radla-tiveless rate of the photoexcited Ru complex molecules decreases, which results In the increase of luminescence lifetime and efficiency. The structure of the Ru com-plex has an important impact on the interaction with DNA. The [Ru(bpy)2(7-CH3-dppz)]2+shows the longest luminescence lifetime (about 382 ns), while the [Ru(bpy)2(7-F-dppz)]2+ shows the shortest lifetime (about 65 ns). The possible origin of the luminescence dynamics is discussed.

  11. Study of transient luminescence of three kinds of Ru complexes bound to DNA

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The transient luminescence of three kinds of ruthenium complexes [Ru(bpy)2(7-CH3-dppz)]2+, [Ru(bpy)2(7-F-dppz)]2+ and [Ru(phen)2(7-F-dppz)]2+ bound to calf thy-mus DNA (ctDNA) has been studied by using the time-resolved spectroscopy. The results show that the luminescence is due to the radiative decay from the charge-transfer states to the ground state. By the interaction with DNA, the radia-tiveless rate of the photoexcited Ru complex molecules decreases, which results in the increase of luminescence lifetime and efficiency. The structure of the Ru com-plex has an important impact on the interaction with DNA. The [Ru(bpy)2(7-CH3-dppz)]2+ shows the longest luminescence lifetime (about 382 ns), while the [Ru(bpy)2(7-F-dppz)]2+ shows the shortest lifetime (about 65 ns). The possible origin of the luminescence dynamics is discussed.

  12. Aggregated Modelling for Wind Farms for Power System Transient Stability Studies

    DEFF Research Database (Denmark)

    Liu, Hongzhi; Chen, Zhe

    2012-01-01

    Wind energy is consistently attracting great research effort and actively developed in many countries. As a result, the penetration level of wind power in the power grid is increasing as well as the size of wind farms. A large-scale wind farm may consist of hundreds of wind turbines and its total...... on a wind farm with permanent magnet synchronous generator (PMSG) wind turbines. Simulation results of the aggregated models and the detailed model are compared and analyzed respectively to prove the effectiveness of the aggregating techniques....... installed capacity could be at a level of 1000MW or even more. Consequently, the large-scale wind farm could seriously impact the operation and control of the grid. To represent a large-scale wind farm, aggregated modelling takes advantage of fast computation and simplified implementation compared...... to detailed modelling that models every wind turbines individually and the interconnections among them. In this paper, three aggregated modelling techniques, namely, multi-machine equivalent aggregation, full aggregation and semi-aggregation are presented for power system transient stability studies based...

  13. Transient analysis and performance studies of two tubular photobioreactors for outdoor culture of Spirulina

    Energy Technology Data Exchange (ETDEWEB)

    Prakash, J.; Torzillo, G.; Pushparaj, B.; Carlozzi, P.; Materassi, R. [Consiglio Nazionale delle Ricerche, Florence (Italy). Centro di Studio dei Microhanismi Autotrofi

    1995-08-01

    A mathematical model to make a transient thermal analysis and to estimate the incident solar energy for two designs of tubular photobioreactor installed outdoors is presented here. In the first photobioreactor design the tubes were arranged in one plane, whereas in the second the tubes were arranged in two planes. The model was validated by comparing the experimental data and predicted values of culture temperature. Both the input solar energy and culture temperature in a tubular photobioreactor may be predicted with a reasonable degree of accuracy by employing the model. The performance of the two photobioreactors for mass culture of Spirulina was also studied in relation to their design and culture temperature. The average biomass yield obtained in one-plane and two-plane photobioreactors were (dry weight) 23.7 g m{sup -2} day{sup -1} and 27.8 g m{sup -2} day{sup -1} respectively. Such biomass yields corresponded to a volumetric productivity of (dry weight) 0.466 g litre{sup -1} day{sup -1} in the one-plane reactor and 1.5 g litre{sup -1} day{sup -1} in the two-plane reactor. We further observed that biomass yield could be increased by about 21% when the culture temperature was maintained at the optimal value of 35{sup o}C compared to another culture in which temperature changed according to the ambient temperature from 20 to 39{sup o}C during the day. (author)

  14. Comprehensive transient-state study for CARMENES NIR high-thermal stability

    Science.gov (United States)

    Becerril, Santiago; Sánchez, Miguel A.; Cárdenas, M. C.; Rabaza, Ovidio; Ramón, Alejandro; Abril, Miguel; Costillo, Luis P.; Morales, Rafael; Rodríguez, Alicia; Amado, Pedro J.

    2010-07-01

    CARMENES has been proposed as a next-generation instrument for the 3.5m Calar Alto Telescope. Its objective is finding habitable exoplanets around M dwarfs through radial velocity measurements (m/s level) in the near-infrared. Consequently, the NIR spectrograph is highly constraint regarding thermal/mechanical requirements. Indeed, the requirements used for the present study limit the thermal stability to +/-0.01K (within year period) over a working temperature of 243K in order to minimise radial velocity drifts. This can be achieved by implementing a solution based on several temperature-controlled rooms (TCR), whose smallest room encloses the vacuum vessel which houses the spectrograph's optomechanics. Nevertheless, several options have been taken into account to minimise the complexity of the thermal design: 1) Large thermal inertia of the system, where, given a thermal instability of the environment (typically, +/-0.1K), the optomechanical system remains stable within +/-0.01K in the long run; 2) Environment thermal control, where thermal stability is ensured by controlling the temperature of the environment surrounding the vacuum vessel. The present article also includes the comprehensive transient-state thermal analyses which have been implemented in order to make the best choice, as well as to give important inputs for the thermal layout of the instrument.

  15. Voltage-clamp studies of transient inward current and mechanical oscillations induced by ouabain in ferret papillary muscle.

    Science.gov (United States)

    Karagueuzian, H S; Katzung, B G

    1982-06-01

    1. We studied the effects of a toxic concentration of ouabain on transmembrane electrical activity and on mechanical behaviour of right ventricular papillary muscles from ferrets in a single sucrose-gap using current clamp and voltage clamp.2. Ouabain (1.4-1.8 muM) induced oscillatory after-potentials and after-concentrations in current-clamp experiments. Voltage clamp showed that the oscillatory after-potential was caused by a transient inward current, similar to that in Purkinje fibres.3. The transient current had a sigmoidal dependence on the preceding (activating) voltage step V1, with a treshold around -13 mV and a plateau between +10 and 20 mV. There was a decline in current amplitude for more positive clamps. When activated by a fixed V1 voltage step, and measured at different repolarization levels V2, the transient current manifested an inverse dependence on V2 between -50 and -10 mV. No outward transient current could be detected. Total replacement of Na in the bathing medium by Tris or by sucrose abolished the transient current.4. Ouabain caused an increase of phasic (twitch) tension responses to voltage steps at all potentials without shifting the curve relating these variables on the voltage axis. The drug evoked an even greater increase in the tonic tension responses.5. After prolonged exposure, oscillatory mechanical responses were frequently recorded during positive voltage steps. Unlike the after-contraction, these mechanical fluctuations were not consistently damped and were not accompanied by detectable synchronous current fluctuations. Catecholamines and dibutyryl cyclic AMP markedly reduced the amplitude of the tonic contraction and the mechanical oscillations but increased their frequency. Caffeine had no effect on the tonic contraction amplitude but abolished the fluctuations.6. These results support the proposal that Ca is transiently released from the overloaded sarcoplasmic reticulum in ouabain-intoxicated muscle and may evoke oscillatory

  16. Analytical study of the liquid phase transient behavior of a high temperature heat pipe

    Science.gov (United States)

    Roche, Gregory Lawrence

    1988-09-01

    The transient operation of the liquid phase of a high temperature heat pipe is studied. The study was conducted in support of advanced heat pipe applications that require reliable transport of high temperature drops and significant distances under a broad spectrum of operating conditions. The heat pipe configuration studied consists of a sealed cylindrical enclosure containing a capillary wick structure and sodium working fluid. The wick is an annular flow channel configuration formed between the enclosure interior wall and a concentric cylindrical tube of fine pore screen. The study approach is analytical through the solution of the governing equations. The energy equation is solved over the pipe wall and liquid region using the finite difference Peaceman-Rachford alternating direction implicit numerical method. The continuity and momentum equations are solved over the liquid region by the integral method. The energy equation and liquid dynamics equation are tightly coupled due to the phase change process at the liquid-vapor interface. A kinetic theory model is used to define the phase change process in terms of the temperature jump between the liquid-vapor surface and the bulk vapor. Extensive auxiliary relations, including sodium properties as functions of temperature, are used to close the analytical system. The solution procedure is implemented in a FORTRAN algorithm with some optimization features to take advantage of the IBM System/370 Model 3090 vectorization facility. The code was intended for coupling to a vapor phase algorithm so that the entire heat pipe problem could be solved. As a test of code capabilities, the vapor phase was approximated in a simple manner.

  17. A jet-stirred reactor for transient studies of char gasification

    Energy Technology Data Exchange (ETDEWEB)

    Calo, J.M.; Suuberg, E.M.; Hradil, G.; Perkins, M.T.; Lilly, W.D.

    1986-01-01

    For some time now in our laboratory we have been using well-mixed, ''gradientless'' reactors to study the dynamics of gas-carbon reactions. In the past we have used a mechanically-stirred, Berty-type reactor to examine the kinetics of carbon dioxide and steam gasification of chars. More recently, we have been involved in investigating the behavior of ''active sites'' in certain carbonaceous chars. As a result of the requirements of this work, we were led to the development of a jet-stirred, ''gradientless'' reactor. The current paper describes the design, development and application of this reactor to char gasification studies. The research project for which the reactor was developed is concerned with the study of the nature and behavior of ''active sites'' in the gasification of chars produced from synthesized model compounds, primarily those of the phenol-formaldehyde family of resins. One of the tasks defined for this project was to conduct transient kinetic studies on the gasification of these model compound chars, for both unlabelled and /sup 13/C-labelled resins. Due to the requirements of the expense of the labelled resins we were led to a design that minimized the relatively large sample requirements of the existing autoclave reactor. Once the necessity for developing a new reactor was realized, it was decided to employ jet-mixing in order to avoid some of the potential complexities of mechanical mixing under the particular operating conditions dictated by the nature of the reaction system. 6 refs., 8 figs., 1 tab.

  18. Study on transient beam loading compensation for China ADS proton linac injector II

    CERN Document Server

    Gao, Zheng; Wang, Xian-Wu; Chang, Wei; Zhang, Rui-Feng; Zhu, Zheng-Long; Zhang, Sheng-Hu; Chen, Qi; Powers, Tom

    2016-01-01

    Significant transient beam loading effects were observed during beam commissioning tests of prototype II of the injector for the Accelerator Driven Sub-critical (ADS) system, which took place at the Institute of Modern Physics, Chinese Academy of Sciences, between October and December 2014. During these tests experiments were performed with CW operation of the cavities with pulsed beam current, and the system was configured to make use of a prototype digital low level radio frequency (LLRF) controller. The system was originally operated in pulsed mode with a simple PID feedback control algorithm, which was not able to maintain the desired gradient regulation during pulsed 10 mA beam operations. A unique simple transient beam loading compensation method which made use of a combination of PI feedback and feedforward control algorithm was implemented in order to significantly reduce the beam induced transient effect in the cavity gradients. The superconducting cavity field variation was reduced to less than 1.7%...

  19. Study of rapid transient explosive boiling under short-pulsed laser heating

    Institute of Scientific and Technical Information of China (English)

    JIN Renxi; HUAI Xiulan; LIU Dengying

    2004-01-01

    Using acetone, ethanol, water and acetone-water mixture as test liquids, the rapid transient explosive boiling (RTEB) taking place under short-pulsed laser heating is observed in experiment. The behaviors of temperature variation are investigated via transient temperature measurement. The vapor bubble behaviors of RTEB are captured by high-speed photography, and the difference between RTEB and normal boiling is analyzed. The boiling heat transfer of RTEB is also discussed. It shows that the character of RTEB is far different from normal boiling.

  20. Prognostic significance of transient myocardial ischaemia after first acute myocardial infarction: five year follow up study

    DEFF Research Database (Denmark)

    Mickley, H; Nielsen, J R; Berning, J

    1995-01-01

    OBJECTIVE: To assess the five year prognostic significance of transient myocardial ischaemia on ambulatory monitoring after a first acute myocardial infarction, and to compare the diagnostic and long term prognostic value of ambulatory ST segment monitoring, maximal exercise testing...... episodes of transient ST segment depression, of which 98% were silent. Over a mean of 5 (range 4 to 6) years of follow up, patients with ambulatory ischaemia were no more likely to have objective end points than patients without ischaemic episodes. If, however, subjective events were included...

  1. Risk factors in transient osteoporosis: a retrospective study on 23 cases.

    Science.gov (United States)

    Trevisan, Carlo; Klumpp, Raymond; Compagnoni, Riccardo

    2016-10-01

    The aim of this study is to verify the prevalence of risk factors for transient osteoporosis (TO) in a cohort of patients selected by strict diagnostic criteria. Retrospective observational cohort study on outpatients' data. Inclusion criteria were: (1) acute onset of pain at a lower limb joint exacerbated by weight bearing; (2) no history of trauma, tumors, rheumatic diseases, or infection; (3) presence bone marrow edema on MRI in a weight bearing joint without signs of intraarticular lesions; (4) no hyperesthesia and/or allodynia and/or sweeting changes. The following risk factors were search for in all patients: (1) previous episode of TO; (2) disorders of bone metabolism; (3) cigarette smoke; (4) sudden lower limb overuse; (5) presence of osteoporosis/osteopenia. Twenty-three patients (8 females, 15 males, mean age 48.4 years) fulfilled the inclusion criteria. An average of 1.96 risk factors for TO was present in the cohort. The most frequent risk factor was overuse (in 15 patients, 65.2 %) and the second risk factor was bone metabolism disorders (in 10 patients, 43.5 %). Seven patients (30.4 %) were heavy smokers (more than 20 cigarettes per day) and seven patients showed a previous episode of TO. Six patients (26.1 % of the overall cohort but 60 % of those investigated with DEXA) resulted osteoporotic or osteopenic. Our results suggest there are risk factors that must be investigated in these patients. The presence of these risk factors might support the thesis that their disorder is tied to a decoupling between microdamage accumulation and self-reparative ability of bone tissue. The identification of risk factors with a precise diagnostic pathway can accelerate the diagnostic process and reduce recurrences.

  2. A new method for studying the 3D transient flow of misaligned journal bearings in flexible rotor-bearing systems

    Institute of Scientific and Technical Information of China (English)

    Qiang LI; Shu-lian LIU; Xiao-hong PAN; Shui-ying ZHENG

    2012-01-01

    The effects of journal misalignment on the transient flow of a finite grooved journal bearing are presented in this study.A new 3D computational fluid dynamics (CFD) analysis method is applied.Also,the quasi-coupling calculation of transient fluid dynamics of oil film in journal bearing and rotor dynamics is considered in the analysis.Based on the structured mesh,a new approach for mesh movement is proposed to update the mesh volume when the journal moves during the fluid dynamics simulation of an oil film.Existing dynamic mesh models provided by FLUENT are not suitable for the transient oil flow in journal bearings.The movement of the journal is obtained by solving the moving equations of the rotor-bearing system with the calculated film pressure as the boundary condition of the load.The data exchange between fluid dynamics and rotor dynamics is realized by data files.Results obtained from the CFD model were consistent with previous experimental results on misalignedjournal bearings.Film pressure,oil film force,friction torque,misalignment moment and attitude angle were calculated and compared for misaligned and aligned journal bearings.The results indicate that bearing performances are greatly affected by misalignment which is caused by unbalanced excitation,and the CFD method based on the fluid-structure interaction (FSI) technique can effectively predict the transient flow field ofa misaligned journal bearing in a rotor-bearing system.

  3. Experimental study on Transient Natural Convection in a Cube Enclosure with an Isolated Vertical Cyclically Heated Plate

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    The low frequency cyclical transient natural convection in a cube enclosure with an internal isolated vertical heated plate was investigated experimentally.A computer-aided experimental system was designed to generate the cyclical heating power input and also used for data reduction.The effects of the cyclic heating power input amplitude(from 0 to 8 W) and frequency(form 1/5400s-1 to 1/600s-1) as well as the per-cycle time-average power input(from 8 to 24 W)on the transient and time-average Nusselt number were parametrically studied.It was found that for such cyclical transient natural convection with low frequency,the plate heating power input amplitude and frequency have little effects on the time-average Nusselt number as long as the cyclical time-average heating power input remains the same,although the transient Nusselt number may be significantly affected.Therefore,the modified Grashof number based on the plate average heat flux can be used to characterize the time-average heat transfer process.The plate time-average Nusselt number is about 15% less than the infinite-space Nusselt number,The location of the isolated plate in enclosure does not appreciably influence the time-average heat transfer characteristics of the plate.

  4. A PRELIMINARY STUDY OF EXPERT SYSTEM FOR MINING UNDER STRUCTURES

    Institute of Scientific and Technical Information of China (English)

    吴侃; 何国清; 曹立明

    1991-01-01

    The expert system MUST (Mining Under Structures) shown in this paper and established by the authors is a preliminary expert system to solve the policy-making problems formining under structures by means of computers instead of humanbeing. Based on the experience of relative experts,the authors established a knowledge base about the minings under structures ,researched into reasonable method to simulate thinking processes of human experts when they are solvin8 the problems, established the network of an expert system and named it'MUST system'MUST system uses the method of the structural system analysis approach. A kind of methods of Turbo Prolog and Fortran 77 language alternations is designed to meet the needs of exchange information within the MUST system. Based on this kind of methods MUST system has been constructed and realised on IBM-PC computer. For verifying the correctness. suitability and reliablity of MUST system,some practical examples of minings under structures were tentatively solved using MUST system ,whose results are satisfactory.

  5. The Myres Hill remote sensing intercomparison study: preliminary results

    Science.gov (United States)

    Clive, P. J. M.; Chindurza, I.; Ravey, I.; Bass, J.; Boyle, R. J.; Jones, P.; Lang, S. J.; Bradley, S.; Hay, L.; Oldroyd, A.; Stickland, M.

    2008-05-01

    Two remote sensing techniques (SODAR and LIDAR) have been developed for measuring wind speed and turbulence from ground level up to altitudes of 300 m or higher. Although originally developed in the defence sector, these techniques are now generating considerable interest in the renewable energy and meteorological sectors. Despite the benefits of these instruments they are not yet generally accepted for due diligence measurements by wind energy developers and financial institutions. There is a requirement for a series of independent assessments of these new metrology techniques, comparing their measurements with the approved cup-type anemometer readings. This is being addressed at TUV NEL's Myres Hill wind turbine test site in a measurement programme supported by the DIUS National Measurement Systems Measurement for Innovators scheme and a consortium of 21 industrial collaborators. Data from SODAR and LIDAR systems are being compared with results from cup-type anemometers mounted at different heights on an 80m meteorological mast. An ultrasonic sensor is also mounted on the mast. The objective of the test programme is to assess the effectiveness of SODAR and LIDAR wind speed measurement techniques under different operating regimes and atmospheric conditions. Results from the measurements will provide definitive data on the performance of the remote wind speed sensing techniques under test on complex terrain typical of many wind farm sites. Preliminary measurements based on data acquired during the initial measurement campaign are presented.

  6. Preliminary study of a dispersed fringe type sensing system

    Institute of Scientific and Technical Information of China (English)

    Yong Zhang; Gen-Rong Liu; Yue-Fei Wang; Ye-Ping Li; Ya-Jun Zhang; Liang Zhang

    2009-01-01

    Telescopes with large aspherical primary mirrors collect more light and are therefore sought after by astronomers. Instead of using a single large one-piece mirror, smaller segments can be assembled into a useable telescopic primary. Because the seg-ments must fit together to create the effect of a single mirror, segmented optics present unique challenges to the fabrication and testing that are absent in monolithic optics. A dispersed fringe sensor (DFS) using a broadband point source is an efficient method for cophasing and is also highly automated and robust. Unlike the widely adopted Shack-Hartmann Wavefront sensor and curvature wavefront sensor with edge sensors for cali-bration of relative pistons, DFS can estimate the piston between segments by only using the spectrum formed by the transmissive grating's dispersion, and therefore can replace the edge sensors, which are difficult to calibrate. We introduce the theory of the DFS and Dispersed Hartmann Sensor (DHS) for further utilization of the coarse phasing method of DFS. According to the theory, we bring out the preliminary system design of the cophas-ing experimental system based on DFS and DHS which is now established in our institute. Finally, a summary is reached.

  7. Preliminary study on mechanics-based rainfall kinetic energy

    Directory of Open Access Journals (Sweden)

    Yuan Jiuqin Ms.

    2014-09-01

    Full Text Available A raindrop impact power observation system was employed to observe the real-time raindrop impact power during a rainfall event and to analyze the corresponding rainfall characteristics. The experiments were conducted at different simulated rainfall intensities. As rainfall intensity increased, the observed impact power increased linearly indicating the power observation system would be satisfactory for characterizing rainfall erosivity. Momentum is the product of mass and velocity (Momentum=MV, which is related to the observed impact power value. Since there is no significant difference between momentum and impact power, observed impact power can represent momentum for different rainfall intensities. The relationship between momentum and the observed impact power provides a convenient way to calculate rainfall kinetic energy. The value of rainfall kinetic energy based on the observed impact power was higher than the classic rainfall kinetic energy. The rainfall impact power based kinetic energy and the classic rainfall kinetic energy showed linear correlation, which indicates that the raindrop impact power observation system can characterize rainfall kinetic energy. The article establishes a preliminary way to calculate rainfall kinetic energy by using the real-time observed momentum, providing a foundation for replacing the traditional methods for estimating kinetic energy of rainstorms.

  8. Utilization of Optimal Study Design for Maternal and Fetal Sheep Propofol Pharmacokinetics Study: A Preliminary Study

    Science.gov (United States)

    Sherwin, Catherine M. T.; Ngamprasertwong, Pornswan; Sadhasivam, Senthilkumar; Vinks, Alexander A.

    2017-01-01

    Multiple blood samples are generally required for measurement of pharmacokinetic (PK) parameters. D-optimal design is a popular and frequently used approach for determination of sampling time points in order to minimize the number of samples, while optimizing the estimation of PK parameters. Optimal design utilizing ADAPT (v5, BSR, University of Southern California, Los Angeles) developed a sparse sampling strategy to determine measurement of propofol in pregnant sheep. Propofal was administered as supplemental anesthetic agent to inhalation anesthesia to mimic anesthesia for open fetal surgery. In our preliminary study, propofol 3 mg/kg was given as a bolus to the ewe, followed by propofol infusion at rate 450 mcg/kg/min for 60 minutes, then decreased to 75 mcg/kg/min for 90 more minutes and then ceased. A three compartment model described the PK parameters with the fetus assumed as the third compartment. Initially, sampling times were chosen from thirteen time points as previously stated in the literature. Using priori propofol PK estimates, the final 9 sample time points were proposed in an optimal design with a change in infusion rate occurring between 65 and 75 minutes and sampling proposed at 5, 15, 25, 65, 75, 100, 110, 150, and 180 minutes. D-optimal design optimized the number and timing of samplings, which led to a reduction of cost and man power in the study protocol while preserving the ability to estimate propofol PK parameters in the maternal and fetal sheep model. Initial evaluation of samples collected from three sheep using the optimal design strategy confirmed the performance of the design in obtaining effective PK parameter estimates. PMID:24219004

  9. Experimental and analytical study of stability characteristics of natural circulation boiling water reactors during startup transient

    Science.gov (United States)

    Woo, Kyoungsuk

    Two-phase natural circulation loops are unstable at low pressure operating conditions. New reactor design relying on natural circulation for both normal and abnormal core cooling is susceptible to different types of flow instabilities. In contrast to forced circulation boiling water reactor (BWR), natural circulation BWR is started up without recirculation pumps. The tall chimney placed on the top of the core makes the system susceptible to flashing during low pressure start-up. In addition, the considerable saturation temperature variation may induce complicated dynamic behavior driven by thermal non-equilibrium between the liquid and steam. The thermal-hydraulic problems in two-phase natural circulation systems at low pressure and low power conditions are investigated through experimental methods. Fuel heat conduction, neutron kinetics, flow kinematics, energetics and dynamics that govern the flow behavior at low pressure, are formulated. A dimensionless analysis is introduced to obtain governing dimensionless groups which are groundwork of the system scaling. Based on the robust scaling method and start-up procedures of a typical natural circulation BWR, the simulation strategies for the transient with and without void reactivity feedback is developed. Three different heat-up rates are applied to the transient simulations to study characteristics of the stability during the start-up. Reducing heat-up rate leads to increase in the period of flashing-induced density wave oscillation and decrease in the system pressurization rate. However, reducing the heat-up rate is unable to completely prevent flashing-induced oscillations. Five characteristic regions of stability are discovered at low pressure conditions. They are stable single-phase, flashing near the separator, intermittent oscillation, sinusoidal oscillation and low subcooling stable regions. Stability maps were acquired for system pressures ranging 100 kPa to 400 kPa. According to experimental investigation

  10. Pregnancy-associated transient osteoporosis of the hip: results of a case-control study.

    Science.gov (United States)

    Hadji, Peyman; Boekhoff, Jelena; Hahn, Melitta; Hellmeyer, Lars; Hars, Olaf; Kyvernitakis, Ioannis

    2017-12-01

    The etiology and underlying mechanisms of transient of osteoporosis of the hip (TOH) during pregnancy are still unclear, since no systematic analyses exist. Our results support the hypothesis that TOH is a multifactorial disease, which is associated with immobility, dental problems, and lack of exercise in childhood.

  11. Study on transient stability of wind turbine with induction generator based on variable pitch control strategy

    DEFF Research Database (Denmark)

    Zhao, B.; Li, H.; Han, L.

    2011-01-01

    In order to enhance and improve the transient stability of a grid-connected wind turbine generator system under the power grid fault, based on typical pitch control strategy of wind turbine, considering the wind turbine system oscillation caused by the drive-train shaft flexibility, Based on Matlab...

  12. Transient study for a fully compensated export cable in large offshore wind farms

    DEFF Research Database (Denmark)

    Arana Aristi, Iván; Johnsen, I; Holbøll, Joachim

    2010-01-01

    This paper presents the results of switching transient simulations using PSCAD on Walney Offshore Windfarm 1. The model of WOW1 was created based on as-build information from the main components like cables, reactors, filters and switchgear. Energizing operations of the export cable, reactor...

  13. Study on Transient Void Behavior During Reactivity Initiated Accidents Under Low Pressure Condition

    Science.gov (United States)

    Satou, Akira; Maruyama, Yu; Asaka, Hideaki; Nakamura, Hideo

    Series of out-of-pile experiments to obtain the knowledge on the transient void behavior during reactivity initiated accidents are in progress at JAEA. In the present series of experiments, the transient void behavior in a test section of 2 x 2 bundle geometry under atmospheric pressure condition was measured using an impedance technique. The measuring areas and the arrangement of electrodes for the impedance technique were defined on the basis of numerical analyses and scaled model experiments. The comparison was made between the impedance and differential pressure techniques for steady boiling experiments to estimate the accuracy of the impedance technique. The impedance technique showed a good agreement with the void fraction estimated from the differential pressure. The transient void behavior in the bundle geometry was measured using the impedance technique. The void fraction distribution in the bundle cross-section could be quantitatively obtained by the impedance technique. It could be properly confirmed that the transient void behavior depended on both the subcooling of inlet water and the heat generation rate of simulated fuel rods.

  14. An observational study of the upward sensible heat flux by synoptic scale transients

    NARCIS (Netherlands)

    Oerlemans, J.

    1980-01-01

    For eight 30-day periods, two in each season, vertical transient eddy fluxes of sensible heat were computed at the 850, 500 and 200 mb levels. Use was made of NMC analyses and 6-h forecasts of the (w-field available twice a day. Vertical heat fluxes are strong in the Atlantic and Pacific storm track

  15. TRANSIENT AND STEADY STATE STUDY OF PURE AND MIXED REFRIGERANTS IN A RESIDENTIAL HEAT PUMP

    Science.gov (United States)

    The report gives results of an experimental and theoretical investigation of the transient and steady state performance of a residential air-conditioning/heat pump (AC/HP) operating with different refrigerants. (NOTE: The project was motivated by environmental concerns related to...

  16. Designing Transient Learning Spaces in Second Life - a case study based on the Kamimo experience

    Directory of Open Access Journals (Sweden)

    Judith Molka-Danielsen

    2009-12-01

    Full Text Available Through the grant “Virtual Campus for Life Long Learning” (NUV, 2007, we have gained experience in the design and building of a virtual island or “sim” in Second Life for the purpose of education. This paper discusses the virtual representations, tools, context and spaces used in course activities conducted under the project. While SL can replicate the classroom lecture, it gives further opportunities for interactive and active teaching as learning activities can take place in dispersed and diversified virtual spaces. These can be defined as transient spaces insofar as participants, activities and representations change over time. Designing transient learning spaces raises different challenges and opportunities from designing learning in the traditional physical classroom. Challenges include enabling new users to orient themselves in these spaces and how to behave in the new environments, for example. Transient learning spaces also offer new opportunities, such as the ability to design and develop a specific space for each course. The aim of this article is thus to help the teacher and “sim” designers to recognize the potential of transient learning spaces and the factors that influence their effective design.

  17. TRANSIENT AND STEADY STATE STUDY OF PURE AND MIXED REFRIGERANTS IN A RESIDENTIAL HEAT PUMP

    Science.gov (United States)

    The report gives results of an experimental and theoretical investigation of the transient and steady state performance of a residential air-conditioning/heat pump (AC/HP) operating with different refrigerants. (NOTE: The project was motivated by environmental concerns related to...

  18. Evaluation of half-bridge modular multilevel converter model for VSC-HVDC transient stability studies

    DEFF Research Database (Denmark)

    Irnawan, Roni; Silva, Filipe Miguel Faria da; Bak, Claus Leth

    2017-01-01

    is described. This RMS model is then simplified by neglecting the inner/current controller. Both detailed and simplified RMS models are then validated against an accurate electromagnetic (EMT) transient model in a point-to-point (PtP) transmission system with different AC network strength, power directions...

  19. Transient inhibitory effect of methoxychlor on testicular steroidogenesis in rat: an in vivo study.

    Science.gov (United States)

    Vaithinathan, S; Saradha, B; Mathur, P P

    2008-11-01

    Methoxychlor, an organochlorine pesticide, has been reported to induce reproductive abnormalities in male reproductive tract. To get more insight into the mechanism(s) of gonadal toxicity provoked by methoxychlor, we investigated whether treatment with methoxychlor at low observed adverse effect level (LOAEL) would alter the activities of steroidogenic enzymes such as Delta(5)3beta-hydroxysteroid dehydrogenase (3beta-HSD) and Delta(5)17beta-hydroxysteroid dehydrogenase (17beta-HSD), the expression levels of steroidogenic acute regulatory (StAR) protein and androgen binding protein (ABP) in the testis of adult male rats. The experimental rats were exposed to a single dose of methoxychlor (50 mg/kg body weight) orally. The rats were killed at 0, 3, 6, 12, 24 and 72 h following treatment using anesthetic ether and testes were collected, processed and used to measure the activities of 3beta-HSD, 17beta-HSD, levels of hydrogen peroxide produced and the expression levels of StAR protein, and ABP. Methoxychlor administration resulted in a sequential reduction in the expression of StAR protein and activities of 3beta-HSD, 17beta-HSD with concomitant increase in the levels of hydrogen peroxide in the testis. These changes were significant between 6-12 h following treatment. The levels of ABP declined at 6-12 h following exposure to methoxychlor. The present study demonstrates transient effect of methoxychlor at LOAEL on testicular steroidogenesis and the possible role of hydrogen peroxide in mediating these effects.

  20. Transient inhibitory effect of methoxychlor on testicular steroidogenesis in rat: an in vivo study

    Energy Technology Data Exchange (ETDEWEB)

    Vaithinathan, S.; Saradha, B.; Mathur, P.P. [Pondicherry University, Department of Biochemistry and Molecular Biology, School of Life Sciences, Pondicherry (India)

    2008-11-15

    Methoxychlor, an organochlorine pesticide, has been reported to induce reproductive abnormalities in male reproductive tract. To get more insight into the mechanism(s) of gonadal toxicity provoked by methoxychlor, we investigated whether treatment with methoxychlor at low observed adverse effect level (LOAEL) would alter the activities of steroidogenic enzymes such as {delta}{sup 5}3{beta}-hydroxysteroid dehydrogenase (3{beta}-HSD) and {delta}{sup 5}17{beta}-hydroxysteroid dehydrogenase (17{beta}-HSD), the expression levels of steroidogenic acute regulatory (StAR) protein and androgen binding protein (ABP) in the testis of adult male rats. The experimental rats were exposed to a single dose of methoxychlor (50 mg/kg body weight) orally. The rats were killed at 0, 3, 6, 12, 24 and 72 h following treatment using anesthetic ether and testes were collected, processed and used to measure the activities of 3{beta}-HSD, 17{beta}-HSD, levels of hydrogen peroxide produced and the expression levels of StAR protein, and ABP. Methoxychlor administration resulted in a sequential reduction in the expression of StAR protein and activities of 3{beta}-HSD, 17{beta}-HSD with concomitant increase in the levels of hydrogen peroxide in the testis. These changes were significant between 6-12 h following treatment. The levels of ABP declined at 6-12 h following exposure to methoxychlor. The present study demonstrates transient effect of methoxychlor at LOAEL on testicular steroidogenesis and the possible role of hydrogen peroxide in mediating these effects. (orig.)

  1. A Preliminary Study of Seismicity at Ceboruco, Volcano, Nayarit, Mexico

    Science.gov (United States)

    Sanchez, J. J.; Nunez-Cornu, F. J.; Suarez-Plascencia, C.; Trejo-Gomez, E.

    2007-12-01

    Ceboruco Volcano is located northwestern of Tepic-Zacoalco graben (Jalisco, Mexico). Its volcanic activity can be divided in four eruptive cycles differentiated by their volcano explosivity index (VEI) and chemical variations as well. As a result of andesitic effusive activity, during the first cycle the "paleo-Ceboruco" edifice was constructed. The end of this cycle is defined by a plinian eruption (VEI is estimated between 3 and 4) which occurred some 1020 years ago and formed the external caldera. During the second cycle an andesitic dome extruded in the interior of the caldera. The dome, called Dos Equis, collapsed and formed the internal caldera. The third cycle is represented by andesitic lava flows which partially cover the northern and south-southwestern part of the edifice. The last cycle is represented by historic andesitic lava flows located in the southwestern flank of the volcano. In February 2003 as part of an agreement with Nayarit Civil Defense a seismic station was installed in the SW flank of the volcano. The station is equipped with a Marslite (lennartz) digitizer with a 3DLe 1Hz. seismic sensor. Detection system is based on a STA/LTA recording algorithm. More than 2000 small earthquakes have been attributed to various local sources, and some of this earthquakes are possibly located beneath Ceboruco volcano. A preliminary classification separates high frequency and low frequency seismic events. The sources of high frequency earthquakes appear to be distributed as evidenced from waveforms variety and changing S-P arrivals separations. The low frequency seismic events also show varying signatures and some of them exhibit extended coda, including some monochromatic character.

  2. Transient osteoporosis.

    Science.gov (United States)

    Korompilias, Anastasios V; Karantanas, Apostolos H; Lykissas, Marios G; Beris, Alexandros E

    2008-08-01

    Transient osteoporosis is characterized primarily by bone marrow edema. The disease most commonly affects the hip, knee, and ankle in middle-aged men. Its cause remains unknown. The hallmark that separates transient osteoporosis from other conditions presenting with a bone marrow edema pattern is its self-limited nature. Laboratory tests usually do not contribute to the diagnosis. Plain radiographs may reveal regional osseous demineralization. Magnetic resonance imaging is used primarily for early diagnosis and monitoring disease progression. Early differentiation from more aggressive conditions with long-term sequelae is essential to avoid unnecessary treatment. Clinical entities such as transient osteoporosis of the hip and regional migratory osteoporosis are spontaneously resolving conditions. However, early differential diagnosis and surgical treatment are crucial for the patient with osteonecrosis of the hip or knee.

  3. Supermassive black hole binaries and transient radio events: studies in pulsar astronomy

    Science.gov (United States)

    Burke-Spolaor, S.

    2011-06-01

    The field of pulsar astronomy encompasses a rich breadth of astrophysical topics. The research in this thesis contributes to two particular subjects of pulsar astronomy: gravitational wave science, and identifying celestial sources of pulsed radio emission. We first investigated the detection of supermassive black hole (SMBH) binaries, which are the brightest expected source of gravitational waves for pulsar timing. We considered whether two electromagnetic SMBH tracers, velocity-resolved emission lines in active nuclei, and radio galactic nuclei with spatially-resolved, flat-spectrum cores, can reveal systems emitting gravitational waves in the pulsar timing band. We found that there are systems which may in principle be simultaneously detectable by both an electromagnetic signature and gravitational emission, however the probability of actually identifying such a system is low (they will represent much less than 1% of a randomly selected galactic nucleus sample). This study accents the fact that electromagnetic indicators may be used to explore binary populations down to the 'stalling radii' at which binary inspiral evolution may stall indefinitely at radii exceeding those which produce gravitational radiation in the pulsar timing band. We then performed a search for binary SMBH holes in archival Very Long Baseline Interferometry data for 3114 radio-luminous active galactic nuclei. One source was detected as a double nucleus. This result is interpreted in terms of post-merger timescales for SMBH centralisation, implications for 'stalling', and the relationship of radio activity in nuclei to mergers. Our analysis suggested that binary pair evolution of SMBHs (both of masses >108M circled bullet) spends less than 500Myr in progression from the merging of galactic stellar cores to within the purported stalling radius for SMBH pairs, giving no evidence for an excess of stalled binary systems at small separations. Circumstantial evidence showed that the relative state

  4. The effect of parental involvement in CBT of anxious children: Preliminary results from a RCT study

    DEFF Research Database (Denmark)

    Esbjørn, Barbara Hoff; Breinholst, Sonja; Reinholdt-Dunne, Marie Louise;

    2011-01-01

    Esbjørn, B. H., Breinholst, S., Reinholdt-Dunne, M. L., & Leth, I. (2011). The effect of parental involvement in CBT of anxious children: Preliminary results from a RCT study. Poster accepted for the Association for Behavioral and Cognitive Therapies, Toronto, Canada.......Esbjørn, B. H., Breinholst, S., Reinholdt-Dunne, M. L., & Leth, I. (2011). The effect of parental involvement in CBT of anxious children: Preliminary results from a RCT study. Poster accepted for the Association for Behavioral and Cognitive Therapies, Toronto, Canada....

  5. Linkages between ocean circulation, heat uptake and transient warming: a sensitivity study

    Science.gov (United States)

    Pfister, Patrik; Stocker, Thomas

    2016-04-01

    Transient global warming due to greenhouse gas radiative forcing is substantially reduced by ocean heat uptake (OHU). However, the fraction of equilibrium warming that is realized in transient climate model simulations differs strongly between models (Frölicher and Paynter 2015). It has been shown that this difference is not only related to the magnitude of OHU, but also to the radiative response the OHU causes, measured by the OHU efficacy (Winton et al., 2010). This efficacy is strongly influenced by the spatial pattern of the OHU and its changes (Rose et al. 2014, Winton et al. 2013), predominantly caused by changes in the Atlantic meridional overturning circulation (AMOC). Even in absence of external greenhouse gas forcing, an AMOC weakening causes a radiative imbalance at the top of the atmosphere (Peltier and Vettoretti, 2014), inducing in a net warming of the Earth System. We investigate linkages between those findings by performing both freshwater and greenhouse gas experiments in an Earth System Model of Intermediate Complexity. To assess the sensitivity of the results to ocean and atmospheric transport as well as climate sensitivity, we use an ensemble of model versions, systematically varying key parameters. We analyze circulation changes and radiative adjustments in conjunction with traditional warming metrics such as the transient climate response and the equilibrium climate sensitivity. This aims to improve the understanding of the influence of ocean circulation and OHU on transient climate change, and of the relevance of different metrics for describing this influence. References: Frölicher, T. L. and D.J. Paynter (2015), Extending the relationship between global warming and cumulative carbon emissions to multi-millennial timescales, Environ. Res. Lett., 10, 075022 Peltier, W. R., and G. Vettoretti (2014), Dansgaard-Oeschger oscillations predicted in a comprehensive model of glacial climate: A "kicked" salt oscillator in the Atlantic, Geophys. Res

  6. Preliminary study of non-isothermal phase change phenomena in vertical Bridgman crystal growth

    Institute of Scientific and Technical Information of China (English)

    LIU Jie; LU WenQiang

    2007-01-01

    Axisymmetric dual reciprocity boundary element method (DRBEM) with augmented items is extended to simulate the heat and mass transfer problems in the vertical Bridgman method (VBM) crystal growth of HgCdTe and CdZnTe. Axial solute concentration redistribution of three regions numerically reappears, and the influence of the pulling rate of the ampoule on it is further studied. Secondly, one dimensional transient phase change phenomena is studied, and non-isothermal phase change phenomena is obtained from the initial transient region through the steady growth region to the final transient region. Thirdly, the two-dimensional axisymmetric phase change interface position, interfacial shape and the temperature field of the melt and the crystal are numerically captured under the condition to arrive at the steady state with zero pulling rate of the ampoule. Finally, the study of transient axisymmetric non-isothermal phase change phenomena is stressed and the results are compared with those in isothermal phase change. The influence of the pulling rate on non-isothermal phase change phenomena is revealed.

  7. Battery energy storage: A preliminary assessment of national benefits (the Gateway Benefits Study)

    Energy Technology Data Exchange (ETDEWEB)

    Akhil, A. [Sandia National Labs., Albuquerque, NM (United States); Zaininger, H. [Zaininger Engineering Co., San Jose, CA (United States); Hurwitch, J.; Badin, J. [Energetics, Inc., Columbia, MD (United States)

    1993-12-01

    Preliminary estimates of national benefits from electric utility applications of battery energy storage through the year 2010 are presented along with a discussion of the particular applications studied. The estimates in this report were based on planning information reported to DOE by electric utilities across the United States. Future studies are planned to refine these estimates as more application-specific information becomes available.

  8. Transient electromagnetic study of basin fill sediments in the Upper San Pedro Basin, Mexico

    Science.gov (United States)

    Bultman, M.W.; Gray, F.

    2011-01-01

    The Upper San Pedro River Basin in Mexico and the United States is an important riparian corridor that is coming under increasing pressure from growing populations and the associated increase in groundwater withdrawal. Several studies have produced three-dimensional maps of the basin fill sediments in the US portion of the basin but little work has been done in the Mexican portion of the basin. Here, the results of a ground-based transient electromagnetic (TEM) survey in the Upper San Pedro Basin, Mexico are presented. These basin fill sediments are characterized by a 10-40 m deep unsaturated surficial zone which is composed primarily of sands and gravels. In the central portion of the basin this unsaturated zone is usually underlain by a shallow clay layer 20-50 m thick. Beneath this may be more clay, as is usually the case near the San Pedro River, or interbedded sand, silt, and clay to a depth of 200-250 m. As you move away from the river, the upper clay layer disappears and the amount of sand in the sediments increases. At 1-2 km away from the river, sands can occupy up to 50% of the upper 200-250 m of the sediment fill. Below this, clays are always present except where bedrock highs are observed. This lower clay layer begins at a depth of about 200 m in the central portion of the basin (250 m or more at distances greater than 1-2 km from the river) and extends to the bottom of most profiles to depths of 400 m. While the depth of the top of this lower clay layer is probably accurate, its thickness observed in the models may be overestimated due to the relatively low magnetic moment of the TEM system used in this study. The inversion routine used for interpretation is based on a one-dimensional geologic model. This is a layer based model that is isotropic in both the x and y directions. Several survey soundings did not meet this requirement which invalidates the inversion process and the resulting interpretation at these locations. The results from these

  9. Numerical study on transient flow in the deep naturally fractured reservoir with high pressure

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    According to the experimental results and the characteristics of the pressure-sensitive fractured formation, a transient flow model is developed for the deep naturally-fractured reservoirs with different outer boundary conditions. The finite element equations for the model are derived. After generating the unstructured grids in the solution regions, the finite element method is used to calculate the pressure type curves for the pressure-sensitive fractured reservoir with different outer boundaries, such as the infinite boundary, circle boundary and combined linear boundaries, and the characteristics of the type curves are comparatively analyzed. The effects on the pressure curves caused by pressure sensitivity module and the effective radius combined parameter are determined, and the method for calculating the pressure-sensitive reservoir parameters is introduced. By analyzing the real field case in the high temperature and pressure reservoir, the perfect results show that the transient flow model for the pressure-sensitive fractured reservoir in this paper is correct.

  10. Numerical study on transient flow in the deep naturally fractured reservoir with high pressure

    Institute of Scientific and Technical Information of China (English)

    LIU YueWu; CHEN WeiLiang; LIU QingQuan

    2009-01-01

    According to the experimental results and the characteristics of the pressure-sensitive fractured for-mation, a transient flow model is developed for the deep naturally-fractured reservoirs with different outer boundary conditions. The finite element equations for the model are derived. After generating the unstructured grids in the solution regions, the finite element method is used to calculate the pressure type curves for the pressure-eensitive fractured reservoir with different outer boundaries, such as the infinite boundary, circle boundary and combined linear boundaries, and the characteristics of the type curves are comparatively analyzed. The effects on the pressure curves caused by pressure sensitivity module and the effective radius combined parameter are determined, and the method for calculating the pressure-sensitive reservoir parameters is introduced. By analyzing the real field case in the high temperature end pressure reservoir, the perfect results show that the transient flow model for the pressure-sensitive fractured reservoir in this paper is correct.

  11. Broadband transient absorption study of photoexcitations in lead halide perovskites: Towards a multiband picture

    Science.gov (United States)

    Anand, Benoy; Sampat, Siddharth; Danilov, Evgeny O.; Peng, Weina; Rupich, Sara M.; Chabal, Yves J.; Gartstein, Yuri N.; Malko, Anton V.

    2016-04-01

    Ultrafast transient pump-probe measurements of thin CH3NH3PbI3 perovskite films over a wide spectral range from 350 to 800 nm reveal a family of photoinduced bleach (PB) and absorption (PA) features unequivocally pointing to the fundamentally multiband character of the underlying electronic structure. Excitation pump-energy dependent kinetics of three long-lived PB peaks at 1.65, 2.55, and 3.15 eV along with a broad PA band shows the involvement of band-edge thermalized carriers in all transitions and at least four, possibly more, electronic bands. The evolution of the transient signatures is described in terms of the redistribution of the conserved oscillator strength of the whole system. The multiband perspective opens up different directions for understanding and controlling photoexcitations in hybrid perovskites.

  12. Excited-State Dynamics of Carotenoids Studied by Femtosecond Transient Absorption Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ingu; Pang, Yoonsoo [Department of Physics and Photon Science, Gwangju (Korea, Republic of); Lee, Sebok [Gwangju Institute of Science and Technology, Gwangju (Korea, Republic of)

    2014-03-15

    Carotenoids, natural antenna pigments in photosynthesis share a symmetric backbone of conjugated polyenes. Contrary to the symmetric and almost planar geometries of carotenoids, excited state structure and dynamics of carotenoids are exceedingly complex. In this paper, recent infrared and visible transient absorption measurements and excitation dependent dynamics of 8'-apo-β-caroten-8'-al and 7',7'-dicyano-7'-apo-β-carotene will be reviewed. The recent visible transient absorption measurements of 8'-apo-β-caroten-8'-al in polar and nonpolar solvents will also be introduced to emphasize the complex excited-state dynamics and unsolved problems in the S{sub 2} and S{sub 1} excited states.

  13. Analytical and Numerical Study of Photocurrent Transients in Organic Polymer Solar Cells

    CERN Document Server

    de Falco, Carlo; Verri, Maurizio; 10.1016/j.cma.2010.01.018

    2012-01-01

    This article is an attempt to provide a self consistent picture, including existence analysis and numerical solution algorithms, of the mathematical problems arising from modeling photocurrent transients in Organic-polymer Solar Cells (OSCs). The mathematical model for OSCs consists of a system of nonlinear diffusion-reaction partial differential equations (PDEs) with electrostatic convection, coupled to a kinetic ordinary differential equation (ODE). We propose a suitable reformulation of the model that allows us to prove the existence of a solution in both stationary and transient conditions and to better highlight the role of exciton dynamics in determining the device turn-on time. For the numerical treatment of the problem, we carry out a temporal semi-discretization using an implicit adaptive method, and the resulting sequence of differential subproblems is linearized using the Newton-Raphson method with inexact evaluation of the Jacobian. Then, we use exponentially fitted finite elements for the spatial...

  14. The Study on On-line Scheduling Algorithm of Imprecise Computation under Transient Overload

    Institute of Scientific and Technical Information of China (English)

    WEIZhenhua; HONGBingrong; QIAOYongqiang; CAIZesu; PENGJunjie

    2003-01-01

    Transient overload always occurs in realtime computer system. An on-line scheduling algorithm of imprecise computation is proposed in this paper to deal with it. This algorithm can be sure of getting acceptable computation result under the condition of overload, and at the same time it can improve the computation precision as much as possible. The system model of imprecise computation and the on-line imprecise computation algorithm are elaborated. And the algorithm is proved correct by simulation.

  15. Optical nonlinearity of organic dyes as studied by Z-scan and transient grating techniques

    Indian Academy of Sciences (India)

    Umakanta Tripathy; R Justin Rajesh; Prem B Bisht; A Subrahamanyam

    2002-12-01

    The excited state absorption cross-section of 5,5′-dichloro-11-diphenylamino- 3,3′-diethyl-10,12-ethylinethiatricarbocyanine perchlorate (IR140) have been measured by using a single beam transmission technique. Z-scan experiments have been used to find out a few nonlinear parameters. The excited state relaxation times have also been measured by using laser induced transient grating (LITG) technique.

  16. Study of carrier recombination transient characteristics in MOCVD grown GaN dependent on layer thickness

    Directory of Open Access Journals (Sweden)

    E. Gaubas

    2013-11-01

    Full Text Available The MOCVD grown GaN epi-layers of different thickness have been examined in order to clarify a role of surface recombination, to separate an impact of radiative and non-radiative recombination and disorder factors. The microwave probed –photoconductivity (MW-PC and spectrally resolved photo-luminescence (PL transients were simultaneously recorded under ultraviolet (UV light 354 nm pulsed 500 ps excitation. The MW-PC transients exhibited the carrier decay components associated with carrier decay within micro-crystals and the disordered structure on the periphery areas surrounding crystalline columns. Three PL bands were resolved within PL spectrum, namely, the exciton ascribed UV-PL band edge for hν>3.3 eV, blue B-PL band for 2.5 < hν < 3.0 eV and yellow Y-PL band with hν < 2.4 eV. It has been obtained that intensity of UV-PL band increases with excitation density, while intensity of B-PL band is nearly invariant. However, intensity of the Y-PL increases with reduction of the excitation density. The Y-PL can be associated with trapping centers. A reduction of UV excitation density leads to a decrease of the relative amplitude of the asymptotic component within the MW-PC transients and to an increase of the amplitude as well as duration of the yellow spectral band (Y-PL asymptotic component. Fractional index α with values 0.5 < α < 0.8 was evaluated for the stretched-exponent component which fits the experimental transients determined by the disordered structure ascribed to the periphery areas surrounding the crystalline columns.

  17. Dual Transformer Model based on Standard Circuit Elements for the Study of Low- and Mid-frequency Transients

    Science.gov (United States)

    Jazebi, Saeed

    This thesis is a step forward toward achieving the final objective of creating a fully dual model for transformers including eddy currents and nonlinearities of the iron core using the fundamental electrical components already available in the EMTP-type programs. The model is effective for the study of the performance of transformers during power system transients. This is very important for transformer designers, because the insulation of transformers is determined with the overvoltages caused by lightning or switching operations. There are also internally induced transients that occur when a switch is actuated. For example switching actions for reconfiguration of distribution systems that offers economic advantages, or protective actions to clear faults and large short-circuit currents. Many of the smart grid concepts currently under development by many utilities rely heavily on switching to optimize resources that produce transients in the system. On the other hand, inrush currents produce mechanical forces which deform transformer windings and cause malfunction of the differential protection. Also, transformer performance under ferroresonance and geomagnetic induced currents are necessary to study. In this thesis, a physically consistent dual model applicable to single-phase two-winding transformers is proposed. First, the topology of a dual electrical equivalent circuit is obtained from the direct application of the principle of duality. Then, the model parameters are computed considering the variations of the transformer electromagnetic behavior under various operating conditions. Current modeling techniques use different topological models to represent diverse transient situations. The reversible model proposed in this thesis unifies the terminal and topological equivalent circuits. The model remains invariable for all low-frequency transients including deep saturation conditions driven from any of the two windings. The very high saturation region of the

  18. Shock induced chemistry in liquids studied with ultrafast dynamic ellipsometry and visible transient absorption spectroscopy.

    Science.gov (United States)

    Dang, N C; Bolme, C A; Moore, D S; McGrane, S D

    2012-10-25

    The response to ultrafast laser shock loading of nine liquids was monitored in an effort to reveal evidence of chemical changes occurring during the first 350 ps following the shock front. In an effort to compare molecular structures possessing a variety of common bonding patterns, data were acquired for the liquids: cyclohexane, cyclohexene, 1,3-cyclohexadiene, benzene, water, acetonitrile, acrylonitrile, tert-butylacetylene, and phenylacetylene. Transient absorption spectra were measured in the spectral region from 440 to 780 nm over shock stress states from 7 to 20 GPa. Ultrafast dynamic ellipsometry was used to measure the shock and particle velocity as well as the shocked refractive index. Significant transient absorption attributed to chemical reaction was observed for shocked phenylacetylene and acrylonitrile. Evidence of volume decreasing chemical reactions was also observed in the ultrafast dynamic ellipsometry data for phenylacetylene and acrylonitrile. The liquid 1,3-cyclohexadiene exhibited volume decreasing reaction in the ultrafast dynamic ellipsometry data but did not exhibit an increase in the transient absorption spectra. There was no evidence of chemical reaction in cyclohexane, cyclohexene, benzene, water, acetonitrile, or tert-butylacetylene in the first 350 ps, despite the application of shock stress that was in many cases well above the reaction threshold observed at microsecond time scales.

  19. Study on transient beam loading compensation for China ADS proton linac injector II

    Science.gov (United States)

    Gao, Zheng; He, Yuan; Wang, Xian-Wu; Chang, Wei; Zhang, Rui-Feng; Zhu, Zheng-Long; Zhang, Sheng-Hu; Chen, Qi; Powers, Tom

    2016-05-01

    Significant transient beam loading effects were observed during beam commissioning tests of prototype II of the injector for the accelerator driven sub-critical (ADS) system, which took place at the Institute of Modern Physics, Chinese Academy of Sciences, between October and December 2014. During these tests experiments were performed with continuous wave (CW) operation of the cavities with pulsed beam current, and the system was configured to make use of a prototype digital low level radio frequency (LLRF) controller. The system was originally operated in pulsed mode with a simple proportional plus integral and deviation (PID) feedback control algorithm, which was not able to maintain the desired gradient regulation during pulsed 10 mA beam operations. A unique simple transient beam loading compensation method which made use of a combination of proportional and integral (PI) feedback and feedforward control algorithm was implemented in order to significantly reduce the beam induced transient effect in the cavity gradients. The superconducting cavity field variation was reduced to less than 1.7% after turning on this control algorithm. The design and experimental results of this system are presented in this paper. Supported by National Natural Science Foundation of China (91426303, 11525523)

  20. Experimental and theoretical studies of transient electron velocity overshoot in GaN

    Energy Technology Data Exchange (ETDEWEB)

    Wraback, M.; Shen, H.; Rudin, S. [U.S. Army Research Laboratory, Sensors and Electron Devices Directorate, AMSRL-SE-EM, 2800 Powder Mill Road, Adelphi, MD 20783 (United States); Bellotti, E. [Electrical and Computer Engineering Department, Boston University, 8 Saint Mary' s Street, Boston, MA 02215-2421 (United States)

    2002-12-01

    We employ an optically detected time-of-flight technique with femtosecond resolution that monitors the change in the electroabsorption due to charge transport in an AlGaN/GaN heterojunction p-i-n diode to measure the electron velocity overshoot in GaN at room temperature. It has been found that electron velocity overshoot occurs at electric fields as low as 105 kV/cm, with the peak transient velocity increasing with E up to {proportional_to}320 kV/cm, at which field a peak velocity of 7.25 x 10{sup 7} cm/s is attained within the first 200 fs after photoexcitation. At higher fields, the increase in transit time with increasing field suggests the onset of negative differential resistance due to intervalley transfer. The existence of transient velocity overshoot at fields lower than the calculated peak steady-state velocity suggests that it occurs while the electrons are primarily in the {gamma} valley. Full zone Monte Carlo calculations imply that the overshoot is associated more with band nonparabolicity in the {gamma} valley than with intervalley transfer at fields less than 325 kV/cm, and, in conjunction with theoretical calculations employing a semiclassical transport model, confirm the importance of this nonparabolicity for the determination of the temporal shape of the transient velocity overshoot curves. (Abstract Copyright [2002], Wiley Periodicals, Inc.)

  1. Ultrafast laser processing of copper: A comparative study of experimental and simulated transient optical properties

    Science.gov (United States)

    Winter, Jan; Rapp, Stephan; Schmidt, Michael; Huber, Heinz P.

    2017-09-01

    In this paper, we present ultrafast measurements of the complex refractive index for copper up to a time delay of 20 ps with an accuracy laser fluences in the vicinity of the ablation threshold. The measured refractive index n and extinction coefficient k are supported by a simulation including the two-temperature model with an accurate description of thermal and optical properties and a thermomechanical model. Comparison of the measured time resolved optical properties with results of the simulation reveals underlying physical mechanisms in three distinct time delay regimes. It is found that in the early stage (-5 ps to 0 ps) the thermally excited d-band electrons make a major contribution to the laser pulse absorption and create a steep increase in transient optical properties n and k. In the second time regime (0-10 ps) the material expansion influences the plasma frequency, which is also reflected in the transient extinction coefficient. In contrast, the refractive index n follows the total collision frequency. Additionally, the electron-ion thermalization time can be attributed to a minimum of the extinction coefficient at ∼10 ps. In the third time regime (10-20 ps) the transient extinction coefficient k indicates the surface cooling-down process.

  2. Preliminary planning study for safety relief valve experiments in a Mark III BWR pressure suppression system

    Energy Technology Data Exchange (ETDEWEB)

    McCauley, E.W.; Holman, G.S.

    1980-04-21

    In response to a request from the Water Reactor Safety Research Division of the US NRC, a preliminary study is provided which identifies key features and consideration involved in planning a comprehensive in-plant Safety Relief Valve experimental program for a Mark III containment design. The report provides identification of program objectives, measurement system requirements, and some details quantifying expected system response. In addition, a preliminary test matrix is outlined which involves a supporting philosophy intended to enhance the usefulness of the experimental results for all members of the program team: experimentalists, analysts, and plant operator.

  3. A comparative study on the ionic liquid [bmim][BF4] and its solution with transient absorption spectroscopy.

    Science.gov (United States)

    Zhu, Guanglai; Wu, Guozhong; Xu, Xinsheng; Ji, Xuehan

    2011-11-01

    A detailed study was explored to compare the transient absorption spectra of the neat 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][BF(4)]) with its solution in water or acetonitrile. It was concluded that the excited triplet state (3)[bmim](+*) was produced after 266 nm laser irradiation, and then the neutral radical [bmim] and the cation radical [bmim] (2+) were formed through two possible paths. The transient absorption spectra of the neat [bmim][BF(4)] and its solution were similar but the reaction kinetics were different due to their different local structures such as dimeric or cluster. The energy transfer between excited [bmim][BF(4)] and β-carotene further affirmed the existence of (3)[bmim](+*). And the reaction that the hydrated electron captured by [bmim](+) to produce [bmim] in solution was observed.

  4. A Preliminary Study of the Western Zhou Building Foundations at Yuntang in Fufeng, Shaanxi

    Institute of Scientific and Technical Information of China (English)

    徐良高; 王巍; 丁晓雷

    2003-01-01

    From autumn 1999 through the year 2000, Zhouyuan Archaeological Team excavated a set of Western Zhou building foundations, which was well preserved and uniquely designed. It is significantly valuable for the research on the ritual system of the Western Zhou Dynasty. We here by try to make a preliminary study on its structure and function with reference of historical literature.

  5. Feasibility and preliminary effectiveness of preoperative therapeutic exercise in patients with cancer: a pragmatic study.

    NARCIS (Netherlands)

    Timmerman, H.; Groot, J.F. de; Hulzebos, H.J.; Knikker, R. de; Kerkkamp, H.E.M.; Meeteren, N.L. van

    2011-01-01

    The aim of this pilot study is to determine the feasibility and preliminary effectiveness of an individually designed preoperative therapeutic exercise program (PreTEP), in patients recently diagnosed with cancer and awaiting elective surgery. The purpose is to improve their physical fitness levels

  6. Preliminary results of a feasibility study for a hard x-ray Kirkpatrick-Baez telescope

    DEFF Research Database (Denmark)

    Joensen, Karsten D.; Gorenstein, Paul; Wood, James L.

    1994-01-01

    the preliminary results of a feasibility study of a multifocus Kirkpatrick-Baez telescope. We conclude that high quality multilayers can be performed on relevant thin large flat substrate with adequate uniformity, and that existing deposition chambers can produce the multilayers at a rate of 0.42 m2 per day, so...

  7. Robot assisted navigated drilling for percutaneous pedicle screw placement: A preliminary animal study

    Directory of Open Access Journals (Sweden)

    Hongwei Wang

    2015-01-01

    Conclusions: The preliminary study supports the view that computer assisted pedicle screw fixation using spinal robot is feasible and the robot can decrease the intraoperative fluoroscopy time during the minimally invasive pedicle screw fixation surgery. As spine robotic surgery is still in its infancy, further research in this field is worthwhile especially the accuracy of spine robot system should be improved.

  8. Feasibility of pulse oximetry in the initial prehospital management of victims of drowning : A preliminary study

    NARCIS (Netherlands)

    Montenij, Leonard J.; de Vries, Wiebe; Schwarte, Lothar; Bierens, Joost J. L. M.

    2011-01-01

    Aim: Immediate delivery of oxygen is the most important treatment for victims of drowning at the rescue site. Monitoring oxygen saturation with pulse oximetry is potentially useful, but its use may be limited by poor peripheral perfusion due to hypothermia. This preliminary study explores the feasib

  9. Correlates of Cigarette Smoking among Male Chinese College Students in China--A Preliminary Study

    Science.gov (United States)

    Li, Kaigang; Kay, Noy S.

    2009-01-01

    The main purpose of this preliminary study was to examine the association between four constructs of the Health Belief Model (HBM) (i.e. perceived severity of smoking-related health problems, perceived susceptibility to smoking-health related problems, perceived barriers to non-smoking and perceived benefits of non-smoking) and cigarette smoking …

  10. Zero-gravity cloud physics laboratory: Experiment program definition and preliminary laboratory concept studies

    Science.gov (United States)

    Eaton, L. R.; Greco, E. V.

    1973-01-01

    The experiment program definition and preliminary laboratory concept studies on the zero G cloud physics laboratory are reported. This program involves the definition and development of an atmospheric cloud physics laboratory and the selection and delineations of a set of candidate experiments that must utilize the unique environment of zero gravity or near zero gravity.

  11. Feasibility and preliminary effectiveness of preoperative therapeutic exercise in patients with cancer: A pragmatic study

    NARCIS (Netherlands)

    Timmerman, H.; Groot, J.F. de; Hulzebos, H.J.; Knikker, R. de; Kerkkamp, H.E.M.; Meeteren, N.L.U. van

    2011-01-01

    The aim of this pilot study is to determine the feasibility and preliminary effectiveness of an individually designed preoperative therapeutic exercise program (PreTEP), in patients recently diagnosed with cancer and awaiting elective surgery. The purpose is to improve their physical fitness levels

  12. Occupational Therapy in the Context of Head Start: A Preliminary Survey Study

    Science.gov (United States)

    Bowyer, Patricia; Moore, Cary C.; Thom, Carly

    2016-01-01

    This preliminary, descriptive study yields information on the utilization of occupational therapy services within Head Start programs. Participants completed an Internet-based survey of 25 questions pertaining to the understanding, scope, and utilization of occupational therapy services. Surveys were completed by 35 respondents nationwide. A total…

  13. A Quantitative Approach to Investigating Spanish HL Speakers' Characteristics and Motivation: A Preliminary Study

    Science.gov (United States)

    Yanguas, Inigo

    2010-01-01

    The present preliminary study empirically investigated Spanish heritage language (HL) speakers in Spanish for native speakers (SNS) college courses. It focused on their attitudes and motivation to improve their HL and on their varying linguistic competences in that language. A well-established second language acquisition (SLA) motivational model…

  14. A preliminary study on electromyographic analysis of the paraspinal musculature in idiopathic scoliosis

    NARCIS (Netherlands)

    Cheung, J.; Halbertsma, J.P.; Veldhuizen, A.G.; Sluiter, W.J.; Maurits, N.M.; Cool, J.C.; van Horn, J.R.

    2005-01-01

    The paraspinal muscles have been implicated as a major causative factor in the progression of idiopathic scoliosis. Therefore, the objectives of this preliminary study were to measure the electromyographic activity (EMG) of the paraspinal muscles to determine its relationship to progression of the s

  15. Early Language and Literacy Development among Young English Language Learners: Preliminary Insights from a Longitudinal Study

    Science.gov (United States)

    Roessingh, Hetty; Elgie, Susan

    2009-01-01

    This article reports on the preliminary findings of a two-staged empirical study aimed at gaining insights into the variables salient in the early language and literacy development of young English language learners (ELL). Increasingly, young ELL, whether foreign-born or Canadian-born, arrive at school with little developed English-language…

  16. Nd:YAG laser treatment of herpes and aphthous ulcers: a preliminary study

    Science.gov (United States)

    Parkins, Frederick M.; O'Toole, Thomas J.; Yancey, John M.

    2000-06-01

    Previously herpes labialis and recurrent aphthous ulcers have not been successfully treated. A preliminary study with a pulsed Nd:YAG laser evaluated the results with a protocol of four minute non-contact exposures for both types of lesions. Most patients experienced relief of symptoms. The progress of herpes lesion was halted and aphthous lesions became desensitized.

  17. School Library Support of Health Education in China: A Preliminary Study

    Science.gov (United States)

    Liu, Geoffrey Z.; Zhang, Wuhong

    2008-01-01

    This preliminary study investigates the current situation of school library support of K-12 health education in China. A survey of 42 school librarians and 115 K-12 teachers from selected schools was conducted to find out their views about school library's role in school health education and their current practice of library use in health…

  18. Preliminary design and parametric study of 1400 m partially earth-anchored cable-stayed bridge

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The preliminary design and parametric study of 1400 m partially earth-anchored cable-stayed bridge are described. Static per-formance of this new type of bridge is discussed. Compared with fully self-anchored cable-stayed bridge, its advantages in fin-ished state are summarized. Based on numerical calculation, effects of several structural parameters on static performance are presented.

  19. Preliminary Study on the Determination of ~(235)U and ~(239)Pu Using Delayed Neutron Counting Method

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The preliminary study on the fast measurements of 235U and 239Pu in samples containing 235U, 239Pu and 235U-239Pu mixture using delayed neutron counting method is introduced. All samples were irradiated for 30 s using the 30 kW Miniature Neutron

  20. Comparison of Brain Activity during Drawing and Clay Sculpting: A Preliminary qEEG Study

    Science.gov (United States)

    Kruk, Kerry A.; Aravich, Paul F.; Deaver, Sarah P.; deBeus, Roger

    2014-01-01

    A preliminary experimental study examined brain wave frequency patterns of female participants (N = 14) engaged in two different art making conditions: clay sculpting and drawing. After controlling for nonspecific effects of movement, quantitative electroencephalographic (qEEG) recordings were made of the bilateral medial frontal cortex and…

  1. Preliminary Study of m(b) Bias at Selected Soviet Seismic Stations.

    Science.gov (United States)

    1986-03-21

    8217-R66 395 PRELIMINARY STUDY OF M(B) BIRS AT SELECTED SOVIET 1/1 SEISMIC STRTIONS(U) SCIENCE APPLICATIONS INTERNATIONAL CORP ARLINGTON VR A S RYRLL...earthquakes in each source region was not given in the ,.t 1980 paper, but in the earlier work it ranged from 35 events for Asia and the Mediter - ranean to

  2. PRELIMINARY STUDY TO PRIMARY EDUCATION FACILITIES (A Comparison Study between Indonesia and Developed Countries

    Directory of Open Access Journals (Sweden)

    Lucy Yosita

    2006-01-01

    Full Text Available This writing is a preliminary study to condition of primary education facilities in Indonesia, and then comparing these with theories as well as various relevant cases aimed to know the problem more obviously. Basically, there is difference between primary education facilities in Indonesia with those in developed countries. Meanwhile on the other hand, the condition as well as the completion of education facility is actually as the main factor contributes to address the purpose of learning process. If building design, interior and also site plan were dynamic in form, space, colour and tools, those would be probably more stimulate activity and influence into the growth of students. However, lastly, it is still required further analysis, as an example analysis to student's behaviour in spaces of learning environment, more detail and within enough time, not only at indoor but also at outdoor.

  3. Detection and Localization of Transient Sources: Comparative Study of Complex-Lag Distribution Concept Versus Wavelets and Spectrogram-Based Methods

    Directory of Open Access Journals (Sweden)

    Bertrand Gottin

    2009-01-01

    Full Text Available The detection and localization of transient signals is nowadays a typical point of interest when we consider the multitude of existing transient sources, such as electrical and mechanical systems, underwater environments, audio domain, seismic data, and so forth. In such fields, transients carry out a lot of information. They can correspond to a large amount of phenomena issued from the studied problem and important to analyze (anomalies and perturbations, natural sources, environmental singularities, …. They usually occur randomly as brief and sudden signals, such as partial discharges in electrical cables and transformers tanks. Therefore, motivated by advanced and accurate analysis, efficient tools of transients detection and localization are of great utility. Higher order statistics, wavelets and spectrogram distributions are well known methods which proved their efficiency to detect and localize transients independently to one another. However, in the case of a signal composed by several transients physically related and with important energy gap between them, the tools previously mentioned could not detect efficiently all the transients of the whole signal. Recently, the generalized complex time distribution concept has been introduced. This distribution offers access to highly concentrated representation of any phase derivative order of a signal. In this paper, we use this improved phase analysis tool to define a new concept to detect and localize dependant transients taking regard to the phase break they cause and not their amplitude. ROC curves are calculated to analyze and compare the performances of the proposed methods.

  4. Transient Studies in Large Offshore Wind Farms, Employing Detailed Circuit Breaker Representation

    DEFF Research Database (Denmark)

    Glasdam, Jakob Bærholm; Bak, Claus Leth; Hjerrild, Jesper

    2012-01-01

    Switching overvoltages (SOV) are considered a possible source of component failures experienced in existing offshore wind farms (OWFs). The inclusion of sufficiently accurate and validated models of the main electrical components in the OWF in the simulation tool is therefore an important issue...... in order to ensure reliable switching operations. Transient measurement results in an OWF are compared with simulation results in PSCAD EMTDC and DigSILENT Power Factory. A user-defined model of the vacuum circuit breaker (VCB) is included in both tools, capable of simulating multiple prestrikes during...

  5. Transient studies in large offshore wind farms, taking into account network/circuit breaker interaction

    DEFF Research Database (Denmark)

    Glasdam, Jacob Bærholm; Bak, Claus Leth; Hjerrild, Jesper

    2011-01-01

    Switching overvoltages (SOV) are considered a possible source of experienced component failures in existing off-shore wind farms (OWFs). The inclusion of sufficiently accurate and validated models of the main components in the OWF in the simulation tool is therefore an important issue in order...... to ensure reliable switching operations. Transient measurement results in an OWF are compared with simulation results in PSCAD EMTDC and DigSILENT Power Factory, where a user-defined model of the vacuum circuit breaker (VCB) is included, capable of simulating multiple prestrikes during the closing operation...

  6. Transient mid-IR study of electron dynamics in TiO2 conduction band.

    Science.gov (United States)

    Sá, Jacinto; Friedli, Peter; Geiger, Richard; Lerch, Philippe; Rittmann-Frank, Mercedes H; Milne, Christopher J; Szlachetko, Jakub; Santomauro, Fabio G; van Bokhoven, Jeroen A; Chergui, Majed; Rossi, Michel J; Sigg, Hans

    2013-04-07

    The dynamics of TiO2 conduction band electrons were followed with a novel broadband synchrotron-based transient mid-IR spectroscopy setup. The lifetime of conduction band electrons was found to be dependent on the injection method used. Direct band gap excitation results in a lifetime of 2.5 ns, whereas indirect excitation at 532 nm via Ru-N719 dye followed by injection from the dye into TiO2 results in a lifetime of 5.9 ns.

  7. CHF Phenomena by Photographic Study of Boiling Behavior due to Transient Heat Inputs

    OpenAIRE

    Jongdoc Park; Katsuya Fukuda; Qiusheng Liu

    2012-01-01

    The transient boiling heat transfer characteristics in a pool of water and highly wetting liquids such as ethanol and FC-72 due to an exponentially increasing heat input of various rates were investigated using the 1.0 mm diameter experimental heater shaped in a horizontal cylinder for wide ranges of pressure and subcooling. The trend of critical heat flux (CHF) values in relation to the periods was divided into three groups. The CHF belonging to the 1st group with a longer period occurs with...

  8. Calculation and Simulation Study on Transient Stability of Power System Based on Matlab/Simulink

    Directory of Open Access Journals (Sweden)

    Shi Xiu Feng

    2016-01-01

    Full Text Available The stability of the power system is destroyed, will cause a large number of users power outage, even cause the collapse of the whole system, extremely serious consequences. Based on the analysis in single machine infinite system as an example, when at the f point two phase ground fault occurs, the fault lines on either side of the circuit breaker tripping resection at the same time,respectively by two kinds of calculation and simulation methods of system transient stability analysis, the conclusion are consistent. and the simulation analysis is superior to calculation analysis.

  9. PHARMACOGNOSTICAL AND PRELIMINARY PHYTOCHEMICAL STUDIES OF CASSIA SOPHERA LINN.

    Directory of Open Access Journals (Sweden)

    Chavan Chetan

    2011-02-01

    Full Text Available Pharmacognostical parameters for the all three parts of Cassia sophera L were studied with the aim of drawing the pharmacopoeial standards for this species. Macroscopical and microscopical characters, physicochemical constants, extractive values of dry powder and its reaction after treatment with chemical reagents were studied. The determination of these characters will aid future investigators in their Pharmacological analyses of this species.

  10. Personality Study of Hawaii Japanese Nonagenarians: Preliminary Findings. Technical Report.

    Science.gov (United States)

    Izutsu, Satoru; Rose, Charles L.

    As part of a larger study of the demographics, family, household, health, diet, activity, functioning, and mental ability of older Japanese people living in Hawaii which will be compared to similar studies conducted in Japan, personality data were obtained from 101 noninstitutionalized Japanese with an average age of 92 years, residing in Hawaii.…

  11. Preliminary studies on some aspects of Kikuyu food habits

    NARCIS (Netherlands)

    Hoorweg, J.C.; Niemeijer, R.

    1980-01-01

    Description of a research project. The studies cover general aspects of Kikuyu food habits such as foods presently in use, the classification of foods and food preferences for children. The emphasises is on the methods employed in these studies which can also be used elsewhere to obtain information

  12. Modeling and Testing of EVs - Preliminary Study and Laboratory Development

    DEFF Research Database (Denmark)

    Yang, Guang-Ya; Marra, Francesco; Nielsen, Arne Hejde;

    2010-01-01

    Electric vehicles (EVs) are expected to play a key role in the future energy management system to stabilize both supply and consumption with the presence of high penetration of renewable generation. A reasonably accurate model of battery is a key element for the study of EVs behavior and the grid...... tests, followed by the suggestions towards a feasible battery model for further studies....

  13. Preliminary toxicological study of Sylgard 184 curing agent

    Energy Technology Data Exchange (ETDEWEB)

    Smith, D.M.; London, J.E.; Drake, G.A.; Thomas, R.G.

    1978-06-01

    The acute oral LD/sub 50//sup 30/ values for mice and rats receiving Sylgard 184 curing agent were greater than 5 g/kg. According to classical guidelines, the compound would be considered slightly toxic or practically nontoxic in both species. Skin application studies in the rabbit demonstrated the compound to be mildly irritating. Eye irritation studies, also in the rabbit, showed that Sylgard 184 curing agent was a mild but transitory irritant. The sensitization study in guinea pigs did not show the resin to be deleterious.

  14. Preliminary toxicological study of Sylgard 184 encapsulating resin

    Energy Technology Data Exchange (ETDEWEB)

    Smith, D.M.; Drake, G.A.; London, J.E.; Thomas, R.G.

    1978-06-01

    The acute oral LD/sub 50//sup 30/ values for Sylgard 184 encapsulating resin in mice and rats were greater than 5 g/kg. According to classical guidelines, the compound would be considered slightly toxic or practically nontoxic in both species. Skin application studies in the rabbit demonstrated this material to be mildly irritating. Eye irritation studies, also in the rabbit, showed that Sylgard 184 encapsulating resin was a mild but transitory irritant. The sensitization study in guinea pigs did not show the resin to be deleterious in this regard.

  15. Hydrogen Gas Retention and Release from WTP Vessels: Summary of Preliminary Studies

    Energy Technology Data Exchange (ETDEWEB)

    Gauglitz, Phillip A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bontha, Jagannadha R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Daniel, Richard C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Mahoney, Lenna A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Rassat, Scot D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wells, Beric E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bao, Jie [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Boeringa, Gregory K. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Buchmiller, William C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Burns, Carolyn A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Chun, Jaehun [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Karri, Naveen K. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Li, Huidong [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Tran, Diana N. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-07-01

    The Hanford Waste Treatment and Immobilization Plant (WTP) is currently being designed and constructed to pretreat and vitrify a large portion of the waste in the 177 underground waste storage tanks at the Hanford Site. A number of technical issues related to the design of the pretreatment facility (PTF) of the WTP have been identified. These issues must be resolved prior to the U.S. Department of Energy (DOE) Office of River Protection (ORP) reaching a decision to proceed with engineering, procurement, and construction activities for the PTF. One of the issues is Technical Issue T1 - Hydrogen Gas Release from Vessels (hereafter referred to as T1). The focus of T1 is identifying controls for hydrogen release and completing any testing required to close the technical issue. In advance of selecting specific controls for hydrogen gas safety, a number of preliminary technical studies were initiated to support anticipated future testing and to improve the understanding of hydrogen gas generation, retention, and release within PTF vessels. These activities supported the development of a plan defining an overall strategy and approach for addressing T1 and achieving technical endpoints identified for T1. Preliminary studies also supported the development of a test plan for conducting testing and analysis to support closing T1. Both of these plans were developed in advance of selecting specific controls, and in the course of working on T1 it was decided that the testing and analysis identified in the test plan were not immediately needed. However, planning activities and preliminary studies led to significant technical progress in a number of areas. This report summarizes the progress to date from the preliminary technical studies. The technical results in this report should not be used for WTP design or safety and hazards analyses and technical results are marked with the following statement: “Preliminary Technical Results for Planning – Not to be used for WTP Design

  16. Ostracism among Gifted Adolescents: A Preliminary Study in Turkey

    Directory of Open Access Journals (Sweden)

    Uzeyir Ogurlu

    2015-11-01

    Full Text Available Ostracism has an influence on psychological and social functioning. The aim of this study is to examine ostracism among gifted students, with regard to gender and grade levels. Also, the relationship between ostracism and intelligence level was investigated. The study was conducted in a gifted education center, with 94 gifted students who were attending middle school (grades 5-8. The Ostracism Experience Scale for Adolescents and Wechsler Intelligence Scale for Children – Revised Form were employed as data collection tools. According to the findings obtained from the study, it is concluded that ostracism did not differ in terms of gender among gifted students. Besides, being socially excluded may be higher in 8th grades than 6th and 7th grades. Also in the study, a positive correlation was found between intelligence level and ostracism. Discussion and suggestions were also provided based on the results.

  17. A preliminary study on limnological stock assessment, productivity ...

    African Journals Online (AJOL)

    use

    productivity and potential fish yield of Omi Dam,. Nigeria ... the world over through growing populations, intensification of .... The concentration of organic substances in water and ... The mean dissolved oxygen recorded in this study is 5.12.

  18. Features and Functions of Journals: A Preliminary Study

    Directory of Open Access Journals (Sweden)

    Bambang Yudi Cahyono

    1997-01-01

    Full Text Available Abstract: This study is intended to describe the features and functions of journals written by EFL learners. The features described include the contents and organization of the journals. The functions examined in this study include sense of purpose and sense of audience in writing. The subjects of the study were students of the first semester who took English intensive course at the English Department of IKIP MALANG. The results of content analysis indicate that journals that the students write contain various themes. Analysis on paragraph organization indicates that paragraphs in the journals generally show adequate development. This study also shows that the student journals reflect sense of purpose and sense of audience in writing.

  19. A PRELIMINARY STUDY OF CERVICOVAGINAL PEROXIDASES AS INDICATORS FOR OVULATION

    Institute of Scientific and Technical Information of China (English)

    XIANGHong-Fa; HANZi-Yan; LIANGZang-Guang; XIESu-Xiang

    1989-01-01

    There were many studies using cervicovaginal peroxidases to predict ovulation. Some resuits suggested that cervieovaginal peroxidases are reliable indicators for ovulation; but others did not. The present study was designed to determine whether the change patterns of ccrvicovaginal guaiacul peroxidase activity in fertile period of Chinese women can also be served as a basis for development of a technique to predict ovulation time in natural family planning.

  20. Anaerobic culture by Total Air Barrier: A preliminary study

    Directory of Open Access Journals (Sweden)

    Soma Sarkar

    2010-03-01

    Full Text Available BackgroundFor study with obligate anaerobes, inoculated platescontaining suitable reduced media need handling andincubation under strict anaerobic condition. Instead ofensuring a confined oxygen free chamber for placing seededplates, same purpose may be achieved by creating total airbarrier to the surface.MethodUpper moist surface of freshly prepared anaerobic media inPetri plates were intimately covered with very thintransparent bacteriological inert sterile polyester sheets.Stock culture of Bacteroides fragilis, ATCC 23745 andClostridium sporogenes, ATCC 11437 were grown in cookedmeat broth and then sub-cultured on respective plates, afterlifting the cover sheets. Sheets were again covered andincubated at 37oC ordinary incubator. To performantimicrobial susceptibility test, similarly covered seededplates with well inoculums were inverted en-block afterstripping sides with the help of a spatula. Now antibiotic diskswere placed on upper bare surfaces. After short pre-diffusion,plates were incubated keeping inoculated surface below.Same study was performed by conventional method usingGaspak.ResultsGood growths were noted in both sets of the study;however discrete colonies appeared more flat in nature intest set. Almost identical zones of inhibition were noted inboth sets of sensitivity study. Seven days old growths incovered blood agar plates were found viable when subculturedin cooked meat broths.ConclusionIsolation, identification and susceptibility study for mostclinically important obligate anaerobes may be performedby simple barrier method after appropriatestandardization.

  1. Blastocyst cryopreservation using solid surface vitrification: A preliminary study

    Directory of Open Access Journals (Sweden)

    Mohan S Kamath

    2011-01-01

    Full Text Available Objective: The objective was to evaluate the effectiveness of a blastocyst cryopreservation program using solid surface vitrification. Setting: This study took place in a university teaching hospital. Study Design: Retrospective observational study. Materials and Methods: Women undergoing frozen embryo transfer cycles over a 4-year period between 2006 and 2010 were studied. The cryopreservation policy followed was a vitrification protocol performed at the blastocyst stage, using a solid surface (nonimmersion method. The post-thaw survival rate, implantation rate, clinical pregnancy rate, live birth rate, and neonatal outcome were recorded. Results: Eighty-one women underwent 86 frozen embryo transfer cycles. Of the 240 blastocysts warmed, 204 survived giving a cryosurvival rate of 85% (204/240. The clinical pregnancy, implantation, miscarriage, ongoing pregnancy, and live birth rates per transfer were 47%, 29%, 12%, 16%, and 23% respectively. Of the 20 live births, there were 16 singletons and 4 twins. Eleven boys and 13 girls were delivered with no major or minor abnormality detected. Conclusion(s: The blastocyst vitrification protocol using the solid surface method is effective with results comparable to fresh blastocyst transfers. While retaining the rapid cooling effect, the nonimmersion technique eliminates the risk of contamination and disease transmission. Larger studies with long-term follow-up data would further confirm the efficacy and safety of this method of vitrification.

  2. [Omeprazole: a new treatment for paranasal sinus polyps in Widal syndrome. Preliminary study].

    Science.gov (United States)

    Serra, J; Piñas, J; Arnaiz, J A; Quesada, P; Naches, S; Lorente, J; Carne, X

    1998-05-01

    A preliminary report is made of the potential therapeutic effect of omeprazol in reducing nasosinusal polyps. This study is based on the empirical observation of nasal airflow improvement in patients suffering from nasosinusal polyposis after administering omeprazol. Different phases of the study suggested that patients with Widal's syndrome benefited the most. Based on the results of this study, we have undertaken a randomized, parallel, double-blind, placebo-controlled clinical trial.

  3. Assessing interpersonal aspects of schizoid personality disorder: preliminary validation studies.

    Science.gov (United States)

    Kosson, David S; Blackburn, Ronald; Byrnes, Katherine A; Park, Sohee; Logan, Caroline; Donnelly, John P

    2008-03-01

    In 2 studies, we examined the reliability and validity of an interpersonal measure of schizoid personality disorder (SZPD) based on nonverbal behaviors and interpersonal interactions occurring during interviews. A total of 556 male jail inmates in the United States participated in Study 1; 175 mentally disordered offenders in maximum security hospitals in the United Kingdom participated in Study 2. Across both samples, scores on the Interpersonal Measure of Schizoid Personality Disorder (IM-SZ) exhibited adequate reliability and patterns of correlations with other measures consistent with expectations. The scale displayed patterns of relatively specific correlations with interview and self-report measures of SZPD. In addition, the IM-SZ correlated in an expected manner with features of psychopathy and antisocial personality and with independent ratings of interpersonal behavior. We address implications for assessment of personality disorder.

  4. Preliminary toxicological study of Sylgard 184 encapsulating resin: curing agent

    Energy Technology Data Exchange (ETDEWEB)

    Smith, D.M.; Drake, G.A.; London, J.E.; Thomas, R.G.

    1978-06-01

    The acute oral LD/sub 50//sup 30/ values for Sylgard 184 (100 parts encapsulating resin plus 10 parts curing agent) were greater than 5 g/kg in rats and mice. According to classical guidelines, the mixture would be considered slightly toxic or practically nontoxic in both species. Skin application studies in the rabbit demonstrated the mixture to be mildly irritating. Eye irritation tests, also in the rabbit, showed the Sylgard 184 mixture to be a mild but transitory irritant. The sensitization study in the guinea pig demonstrated the mixture to be a very mild sensitizer in two of six animals.

  5. Preliminary studies for the LHCb vertex detector vacuum system

    CERN Document Server

    Doets, M; Van Bakel, N; Van den Brand, J F J; van den Brand, Jo

    2000-01-01

    We lay down some general considerations which will serve as a starting point for design studies of a realistic LHCb vertex detector vacuum system. Based on these considerations, we propose a design strategy and identify issues to be further studied. In particular we try to outline some boundary conditions imposed by LHC and LHCb on the vacuum system. We discuss two possibilities for the LHCb vertex detector vacuum system. The preferred strategy uses a differentially pumped vacuum system with the silicon detectors separated from the beam line vacuum. Some estimations on static vacuum pressures and gas flows are presented.

  6. Preliminary studies of inhibitions in Aspergillus flavus with extracts of ...

    African Journals Online (AJOL)

    Administrator

    of lichens on the growth of lower Phycomycetes and. Neurospora ... have indicated the possible use of plant as well as lichen extracts in the control of plant diseases. The extraction, ... under light microscope (*400 objective) for the emergence of germ tube. .... artificial fungicide develop, this study has shown that extracts of ...

  7. Psychiatric morbidity in oral lichen planus: A preliminary study

    Directory of Open Access Journals (Sweden)

    Abhishek Ranjan Pati

    2014-01-01

    Full Text Available Objective: To study the clinical types and association of psychological factors in patients with Oral Lichen Planus (OLP. Materials and Methods: An analytical age- and sex-matched study involved 30 patients with oral lichen planus (group 1 and 30 control subjects (group 2. We applied the following psychometric tests to both groups: General Health Questionnaire (GHQ and Hospital Anxiety and Depression Scale (HADS. Results: The patients with OLP were found to exhibit statistically significant higher anxiety, insomnia, and social dysfunction with the tests that were used (GHQ 24 and HADS than the control group (P > 0.05. The study group likewise exhibited greater depression and somatic symptoms. The mean total of the GHQ and HAD scores were found to be higher in the study group than in the controls (P > 0.05. Among the various types of OLP, patients with the erosive type had higher mean scores for anxiety and insomnia, social dysfunction and depression. Conclusion: In most patients psychiatric morbidity was strongly associated with OLP, which could support its role in the etiopathogenesis of the disease. The higher scores of the General Health Questionnaire and Hospital Anxiety and Depression Scale gave an insight into the hypothesis that psychological factors are associated with the causation of OLP.

  8. Buffalo Harbor Study. Preliminary Feasibility Report. Volume I. Main Report.

    Science.gov (United States)

    1983-04-01

    the Buffalo Ornithological Society . Although these groups are not planning agencies, they represent an important trend in land use planning. The groups...Buffalo Historical Society , 1902. Wilson , Carroll L. Coal: Bridge to the Future, Report of the World Coal Study. Cambridge: Ballinger Publishing Company... Wilson , 1980) PLANNING CONSTRAINTS Federal policy on multiobjective planning, derived from both legislative and executive authorities, establishes and

  9. Burnout among Special Education Administrators: A Preliminary Study

    Science.gov (United States)

    Carter, Susan J.

    2011-01-01

    Research on the extent of stress and burnout among special education administrators is not as well developed as research on the extent of stress and burnout among teachers. This study utilized the Maslach Burnout Inventory to determine levels of stress and burnout among administrators of special education. Results indicated administrators of…

  10. Preliminary study Malaa. Final report; Foerstudie Malaa. Slutrapport

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    Factors of importance for a possible localization of a deep nuclear waste repository at Malaa in northern Sweden are mapped in this study. The geologic structures in the area have been reviewed, mostly from already existing knowledge. Existing infrastructure and necessary improvements are discussed, as well as land use and environment, employment and other social effects. 47 refs, 41 figs, 8 tabs.

  11. Violence Prevention in Middle School: A Preliminary Study

    Science.gov (United States)

    KIllam, Wendy K.; Roland, Catherine B.; Weber, Bill

    2014-01-01

    Violence in schools continues reflecting violence within society. There is a growing need for violence prevention programs within the schools that provide students with the skills needed to cope with interpersonal and relationship is-sues effectively. This study was conducted at a middle school and there were 345 middle school students (6th to 8th…

  12. Preliminary studies in the genus Entoloma in Tasmania - I

    OpenAIRE

    Gates, Genevieve M.; Noordeloos, Machiel

    2007-01-01

    This paper describes 33 new species of Entoloma from wet and dry forests in Tasmania, Australia, based on 8 years of intensive collecting, description and study of the Entoloma mycota. As such it is a precursor to a monographic treatment of the Entolomataceae of Tasmania, to be published in the next few years.

  13. Preliminary studies in the genus Entoloma in Tasmania - I

    NARCIS (Netherlands)

    Gates, Genevieve M.; Noordeloos, Machiel

    2007-01-01

    This paper describes 33 new species of Entoloma from wet and dry forests in Tasmania, Australia, based on 8 years of intensive collecting, description and study of the Entoloma mycota. As such it is a precursor to a monographic treatment of the Entolomataceae of Tasmania, to be published in the next

  14. Study and Preliminary Analysis of Test of Aerosol Migration Mechanism

    Institute of Scientific and Technical Information of China (English)

    CHEN; Lin-lin; SUN; Xue-ting; WEI; Yan-song

    2015-01-01

    TAMM(test of aerosol migration mechanism)is one of the important aspects of Studies on Migration Mechanism of the Source Term under Severe Accident,which is a significant research of the National Large Advanced PWR Research Program.The main task researches the

  15. ENDOPHYTIC FUNGI FROM JATROPHA CURCUS: A PRELIMINARY STUDY

    Directory of Open Access Journals (Sweden)

    Santosh Kumar Singh

    2013-04-01

    Full Text Available Fungal endophytes are ubiquitously reported from the living tissues of healthy plant parts from every host studied so far. These microbes attributed significantly in upraising the caliber of the host to counteract against the different stresses and herbivores, and also some times to improve the host fitness. This study presenting here the endophytic mycoflora of Jatropha curcus, which remain less explored. A total of eighteen species of fungi were isolated from leaf, stem, and roots of Jatropha curcus. The root was heavily colonized by the genera like Alternaria, Cladosporium, and Aspergillus spp. The leaf tissues however showed somewhat greater diversity of endophytic colonization. Drechslera, Curvularia, Bipolaris, Alternaria, and Aspergillus sp. were dominant in to the leaf tissues with strong presence of an unidentified genus. The species richness as well as frequency of colonization of endophytic fungi was more pronounced in the leaf tissues rather than the root and stem. This study reaffirms the fact that endophytes are host and tissues specific. In this regard, the endophytic fungi received in this study, may represent a unique source of one or more of the interesting and useful bioactive compounds similar to those of vinca alkaloid group.

  16. Radioisotope study of Eustachian tube. A preliminary report

    Energy Technology Data Exchange (ETDEWEB)

    De Rossi, G.; Campioni, P.; Vaccaro, A.

    1988-08-01

    Radioisotope studies of Eustachian tube are suggested in the preoperative phase of tympanoplasty, in order to assess tubal drainage and secretion. The use of gamma camera fitted to a computer allowed the AA, to calculate some semi-quantitative parameters for an exact assessment of the radioactivity transit from the tympanic cass up to the pharyngeal cavity, throughout the Eustachian tube.

  17. preliminary multidomain modelling and simulation study of a ...

    African Journals Online (AJOL)

    user

    Renewable energy sources have gained much attention due to the recent energy crisis and ... system for the most energy capture for this case study to be a rotor speed of 5.5rad/s at a height of 10m. .... Thesis, Faculty of California Polytechnic.

  18. Functional Communication Training in Rett Syndrome: A Preliminary Study

    Science.gov (United States)

    Byiers, Breanne J.; Dimian, Adele; Symons, Frank J.

    2014-01-01

    Rett syndrome (RTT) is associated with a range of serious neurodevelopmental consequences including severe communicative impairments. Currently, no evidence-based communication interventions exist for the population (Sigafoos et al., 2009). The purpose of the current study was to examine the effectiveness of functional assessment (FA) and…

  19. From Numbers to Action: A Preliminary Study of Retention.

    Science.gov (United States)

    Greenlee, Shelia Parker; Greenlee, Harry

    This study examined retention at Christopher Newport University (CNU) in Newport News, Virginia, focusing on the demographic characteristics of those students who left the university as well as the reasons why they left. A total of 159 students who had attended CNU during the 1994-95 academic year but who did not re-enroll in the fall of 1995 were…

  20. Dissociation and fantasy proneness in psychiatric patients: a preliminary study.

    Science.gov (United States)

    Merckelbach, Harald; à Campo, Joost; Hardy, Solange; Giesbrecht, Timo

    2005-01-01

    Nonclinical studies found that dissociative experiences are intimately linked to a trait known as fantasy proneness. We examined the links among dissociative symptoms, fantasy proneness, and impulsivity in psychiatric outpatients. Our sample consisted of 22 patients with schizophrenia, 20 patients with a diagnosis of borderline personality disorder, and 19 patients with a major depressive disorder. For the whole sample, levels of dissociation were found to be related to fantasy proneness and impulsivity. There were group differences in dissociative symptoms, with patients with borderline personality disorder reporting more such symptoms than patients with either schizophrenia or major depressive disorder. The overlap between dissociation and fantasy proneness may have important ramifications for studies addressing comorbid phenomena of dissociative symptoms.

  1. Preliminary study of radioactive waste disposal in the vadose zone

    Energy Technology Data Exchange (ETDEWEB)

    1978-09-01

    To investigate the characteristics of the vadose zone with respect to radioactive waste disposal, the mechanics of unsaturated flow in arid regions and the geohydrology of four areas with a deep water table were studied. The studies indicated that (1) arid sites with a water table deeper than 200 m can be found in at least three distinct geologic settings in the western United States, (2) the physics of unsaturated flow in soils and rock with interstitial porosity at low water contents, particularly under thermal gradients, is not yet completely understood, and (3) under certain conditions unsaturated flow can be so slow that analytic modeling of an unflawed repository is unnecessary to prove effective containment.

  2. Cetaceans and fisheries in Kenya coastal waters: a preliminary study.

    OpenAIRE

    Omondi, E.

    1995-01-01

    Of all marine resources characteristic of the Kenyan coast, marine mammals are least studied singly or in association with other resources. In this paper, available records on cetacean catches by district between 1978-1991 inclusive were used to assess the status and trend of their fishery, distribution, and interaction with sharks, clupeids and tuna landings. Spartial and temporal variations in takes were evident. The Mombasa district led in total catch (62.2 tons) while the Tana River distr...

  3. Protocol Development and Preliminary Toxicity Study of CBRN Nanomaterials

    Science.gov (United States)

    2013-12-05

    Schlager, and S.M. Hussain. 2009. Cyrstal Structure Mediates Mode of Cell Death in TiO2. Nanotoxicity. J Nanopart Res. 11(6):1361-1374. Cao, C.J., K...Mouse Keratinocytes. J Nanopart Res. 11:15-24. Toxicology Study No. 87-XE-0EJ5-11 (FY12 Continuation) B-1 Appendix B - Figures 10 - 1 . 0 0 10 - 0 . 7 5

  4. V. PRELIMINARY STUDY ON ISOZYMES OF SHOREA JAVANICA

    Directory of Open Access Journals (Sweden)

    U. JUNIARTI and M. I. J. UMBOH

    1987-01-01

    Full Text Available The detection of genetic variability in natural or man-made populations/ plantations is useful in both basic and applied biology. In addition to the various facets of studies on Shorea javanica already initiated by Torquebiau (1984 and alongside with his recommendations on focus for future research, a study on the genetic aspects of the species should be given important considerations. As the trees are tapped for resin, an important forest product, the genetic basis of the production as well as the range of variation in amount of resin production among t he trees must be known. Coupled with this is a thorough investigation on the differences in pest resistance/susceptability among the trees and their genetic basis. While the assumption (Torquebiau 1984 that trees in natural forest areas are-rarely attacked by diseases because of mycorrhizal fungi is interesting, its confirmation is necessary. If this is true, problems would arise when plants are introduced into a new plantation site as experienced by the Forest Research Institute (Ardikoesuma 1954. Thus, we need to look for pest resistant plants i.e. those that can remain healthy even in the absence of mycorrhizae. The above studies on possible genetic variation could give vital information for development of forest plantations of the species and for breeding and tree improvement strategies. By knowing the extent of genetic variation in natural population or in plantations one could be guided to maintain or increase the genetic base in these areas. Biochemical characters such as isozyme banding patterns have been useful in several areas of plant biology, population genetics, evolution and breeding. Isozymes are detected by starch gel electrophoresis and when their genetic control is established, they could be genetic markers in analyzing variation in morphological or physiological characters. The present study is an attempt to detect the isozymes in leaves, seeds and cotyledons of Shorea

  5. A preliminary metagenomic study of puer tea during pile fermentation.

    Science.gov (United States)

    Lyu, Changyong; Chen, Chaoyin; Ge, Feng; Liu, Diqiu; Zhao, Shenglan; Chen, Dan

    2013-10-01

    Up to now, there has been no report on the taxonomic and functional analysis of the microbial community in fermenting puer tea by pyrosequencing. In this study, metagenomic pyrosequencing was first used in fermenting puer tea to delineate a relatively comprehensive overview of the microbial taxonomy while also preliminarily characterising the functional ontologies of microbial genes present in puer tea pile fermentation. A total of 251 738 pyrosequencing reads (9197 contigs and 145 402 singletons) were generated by pyrosequencing. Taxonomic analysis revealed three dominant bacterial phyla, Actinobacteria (30.08%), Proteobacteria (24.47%) and Firmicutes (20.23%), and one dominant eukaryotic phylum, Ascomycota (15.21%) [corrected]. A total of 58 664 hits were categorised into 28 functional subsystems based on the SEED database. Moreover, two categories, 'metabolism of terpenoids and polyketides' and 'biosynthesis of other secondary metabolites', were selectively analysed and 69 enzyme genes were presented in 16 pathways. The dominant microbes of puer tea fermentation were bacteria in the present study, and yeasts rather than moulds accounted for the overwhelming majority of Eukaryota. The analysis of functional genes and metabolic pathways will be helpful for further study of the mechanism of puer tea fermentation at molecular level. © 2013 Society of Chemical Industry.

  6. Ramadan fasting: Evidence or expert opinion? Results of preliminary studies

    Directory of Open Access Journals (Sweden)

    Maryam Kazemi

    2013-12-01

    Full Text Available Each year, over a billion Muslims fast worldwide during the month of Ramadan.  Through this religious practice, not only will one have spiritual growth, but can improve his/her diet, which is of pivotal importance in this month. Conversely, the available evidence regarding the health benefits of Ramadan fasting is scarce and highly contentious. Although Islam exempts patients from fasting, many of them fast conceivably and their clinical condition is prone to deteriorate. This is due to the persistent gap between current expert knowledge and conclusive, strong evidence regarding the pathophysiologic and metabolic alterations by fasting, and the consensus that healthcare professionals should reach, in order to manage various patient groups during this month. In this review, we summarize the results of our initial studies regarding the effects of Ramadan fasting on some clinical conditions including alterations of body composition. We also go through the important clinical results of patients who have had previous history of cardiovascular disease, type 2 diabetes, asthma and renal colic. Our studies have presented some evidence in favor of Ramadan fasting and encourage those with mentioned diseases to consult their physicians and follow medical and scientific recommendations. We attempt to present some relevant evidence clarify future scopes in this area of study, and provide suggestions for future investigations.

  7. Preliminary Study of Mental Retardation in Rovira (Tolima, Colombia

    Directory of Open Access Journals (Sweden)

    Luis Gustavo Celis

    2008-07-01

    Full Text Available limitationsin performance, significant deficiencyin intelligence and adaptative behavior, causingclinical and social disability. Most patients withmental retardation in Colombia do not receiveclinical genetics evaluation. The aims of thepresent study are to evaluate and characterizea group of patients with mental retardationfrom the population of Rovira. The presentstudy included twenty five patients with mentalretardation from Rovira (Tolima whichwere studied by clinical examination, metabolicscreening (ferric chloride, nitrosonaphtol,silver nitroprusiate, dinitrophenylhydrazineand benedict and cytogenetics (G-Bandingkariotype. Pesticide detection was perfomedby random sampling of water and tomatoes intwenty different places of water distribution,the center of the town and crop fields. A familywith three affected sibs (two females, onemale with mental retardation was identified,suggesting a genetic component. Metabolicscreening was negative and karyotypes werenormal. The analyses performed for organophosphateswere positive in 100% of the samples.Carbamates were positive in 60% of thewater source and 100% of tomato samples. Allthe samples tested were negative for organochlorides.Further studies as molecular fragile-X test, will be performed.

  8. Ramadan fasting: Evidence or expert opinion? Results of preliminary studies

    Directory of Open Access Journals (Sweden)

    1Maryam Kazemi

    2013-11-01

    Full Text Available Each year, over a billion Muslims fast worldwide during the month of Ramadan. Through this religious practice, not only will one have spiritual growth, but can improve his/her diet, which is of pivotal importance in this month. Conversely, the available evidence regarding the health benefits of Ramadan fasting is scarce and highly contentious. Although Islam exempts patients from fasting, many of them fast conceivably and their clinical condition is prone to deteriorate. This is due to the persistent gap between current expert knowledge and conclusive, strong evidence regarding the pathophysiologic and metabolic alterations by fasting, and the consensus that healthcare professionals should reach, in order to manage various patient groups during this month. In this review, we summarize the results of our initial studies regarding the effects of Ramadan fasting on some clinical conditions including alterations of body composition. We also go through the important clinical results of patients who have had previous history of cardiovascular disease, type 2 diabetes, asthma and renal colic. Our studies have presented some evidence in favor of Ramadan fasting and encourage those with mentioned diseases to consult their physicians and follow medical and scientific recommendations. We attempt to present some relevant evidence clarify future scopes in this area of study, and provide suggestions for future investigations.

  9. Motor Empathy in Individuals With Psychopathic Traits: A Preliminary Study.

    Science.gov (United States)

    Khvatskaya, Yelena; Lenzenweger, Mark F

    2016-10-01

    The present laboratory study examined motor empathy in male and female individuals, who were either high or low on psychopathic traits, drawn from a nonclinical university population. Past findings suggest that psychopathic individuals are impaired in affective empathy, but findings on impairments in cognitive empathy are mixed. Research on motor empathy in psychopathy is scarce. The authors hypothesized that individuals high on psychopathic traits would have deficient motor empathy (similar to affective empathy) related to valenced emotion stimuli because of the automatic nature of motor empathy. Potential participants completed the Psychopathic Personality Inventory-Revised (PPI-R). Participants were chosen for the study on the basis of their PPI-R scores. All participants viewed photographic images drawn from a well-established set of stimuli (the International Affective Picture System) and were video recorded while doing so. Intensity for eight emotions (anger, contempt, disgust, fear, sad, joy, surprise, and neutral) in participants' facial expressions was measured objectively using an automated program, the Computer Expression Recognition Toolbox. Individuals high on psychopathic traits as compared with low PPI-R scorers displayed significantly less emotional congruence when viewing negative images. The study results suggest that deficits in motor empathy related to psychopathic trait levels are relatively restricted to negative emotions.

  10. Preliminary studies on cryopreservation of snakehead (Channa striata) embryos.

    Science.gov (United States)

    Mohd Sharifuddin, M; Siti Azizah, M N

    2014-08-01

    This paper reports the findings of the ongoing studies on cryopreservation of the snakehead, Channa striata embryos. The specific objective of this study was to collect data on the sensitivity of C. striata embryo hatching rate to low temperatures at two different developmental stages in the presence of four different cryoprotectants. Embryos at morula and heartbeat stages were selected and incubated in 1M dimethyl sulfoxide (Me2SO), 1M ethylene glycol (EG), 1M methanol (MeOH) and 0.1M sucrose solutions at different temperatures for a period of time. Embryos were kept at 24 °C (control), 15 °C, 4 °C and -2 °C for 5 min, 1h and 3h. Following these treatments, the embryos were then transferred into a 24 °C water bath until hatch to evaluate the hatching rate. The results showed that there was a significant decrease of hatching rate in both developmental stages following exposure to 4 °C and -2 °C at 1h and 3h exposure in each treatment. Heartbeat stage was more tolerant against chilling at -2 °C for 3h exposure in Me2SO followed by MeOH, sucrose and EG. Further studies will be conducted to find the best method to preserve embryos for long term storage.

  11. A Preliminary Study of 3D Printing on Rock Mechanics

    Science.gov (United States)

    Jiang, Chao; Zhao, Gao-Feng

    2015-05-01

    3D printing is an innovative manufacturing technology that enables the printing of objects through the accumulation of successive layers. This study explores the potential application of this 3D printing technology for rock mechanics. Polylactic acid (PLA) was used as the printing material, and the specimens were constructed with a "3D Touch" printer that employs fused deposition modelling (FDM) technology. Unconfined compressive strength (UCS) tests and direct tensile strength (DTS) tests were performed to determine the Young's modulus ( E) and Poisson's ratio ( υ) for these specimens. The experimental results revealed that the PLA specimens exhibited elastic to brittle behaviour in the DTS tests and exhibited elastic to plastic behaviour in the UCS tests. The influence of structural changes in the mechanical response of the printed specimen was investigated; the results indicated that the mechanical response is highly influenced by the input structures, e.g., granular structure, and lattice structure. Unfortunately, our study has demonstrated that the FDM 3D printing with PLA is unsuitable for the direct simulation of rock. However, the ability for 3D printing on manufactured rock remains appealing for researchers of rock mechanics. Additional studies should focus on the development of an appropriate substitution for the printing material (brittle and stiff) and modification of the printing technology (to print 3D grains with arbitrary shapes).

  12. Mukha Mo: A Preliminary Study on Filipino Facial Expressions

    Directory of Open Access Journals (Sweden)

    Richard Jonathan O. Taduran

    2012-12-01

    Full Text Available This study tested the universality hypothesis on facial expression judgment by applying cross-cultural agreement tests on Filipinos. The Facial Action Coding System constructed by Ekman and Friesen (1976 was used as basis for creating stimuli photos that 101 college student observers were madeto identify. Contextualization for each emotion was also solicited from subjects to provide qualitative bases for their judgments. The results showed that for five of the six emotions studied, excepting fear, the majority of the observers judged the expressions as predicted. The judgment of happiness supplied the strongest evidence for universality, having the highest correctness rate and inter-observer agreement. There was also high agreement among observersand between Filipinos and other cultures about the most intense and second most intense emotion signaled by each stimulus for these five emotions. Difficulty with the recognition of fear, as well as its common association with the emotion of sadness, has been found. Such findings shall serve as baseline data for the study of facial expressions in the Philippines.

  13. Effects of Omeprazole on Iron Absorption: Preliminary Study

    Directory of Open Access Journals (Sweden)

    Mahmut Yaşar Çeliker

    2013-09-01

    Full Text Available Objective: Increasing numbers of pediatric and adult patients are being treated with proton pump inhibitors (PPIs. PPIs are known to inhibit gastric acid secretion. Nonheme iron requires gastric acid for conversion to the ferrous form for absorption. Ninety percent of dietary and 100% of oral iron therapy is in the nonheme form. To the best of our knowledge, the effect of PPIs on iron absorption has not been studied in humans. Our study assessed the relationship between omeprazole therapy and iron absorption in healthy subjects. Materials and Methods: We recruited 9 healthy volunteers between June 2010 and March 2011. Subjects with chronic illness, anemia, or use of PPI therapy were excluded. Serum iron concentrations were measured 1, 2, and 3 h after the ingestion of iron (control group. The measurements were repeated on a subsequent visit after 4 daily oral administrations of omeprazole at a dose of 40 mg (treatment group. Results: One female and 8 male volunteers were enrolled in the study with a mean age of 33 years. There was no statistical difference detected between baseline, 1-h, 2-h, and 3-h iron levels between control and treatment groups. Conclusion: Administration of omeprazole for a short duration does not affect absorption of orally administered iron in healthy individuals.

  14. Histological Subgroups in Classic Kaposi Sarcoma: A Preliminary Study

    Directory of Open Access Journals (Sweden)

    Nilüfer Onak Kandemir

    2010-06-01

    Full Text Available Background and Design: Kaposi sarcomas (KS are vascular tumors with a low malignant potential which include overlapping infectious, immunologic, and neoplastic processes. Recently, many histological subtypes have been defined. Material and Method: In the present study, 151 cutaneous classic KS lesions in 56 patients were retrospectively evaluated with regard to histological subtypes. Determination of the subtypes was based on the predominant histopathological component in the lesion. We examined changes in epidermis and dermis along with intratumoral inflammatory response characteristics in the lesions. By defining histopathological variants of the cases, differences regarding subtypes were investigated. Results: Cases that bear the ordinary characteristics of KS and those that can not be classified otherwise, comprised 82..8% of the study group. Twenty-six cases showed consistency with the subtypes outlined in the literature in terms of their histopathological properties. The most common histological subtype was the lymphangiectatic variant in 7.3% of the cases. Bullous (2.6%, lymphangioma like (2.6%, intravascular (2%, and pyogenic granuloma like (2% variants were less common. The most uncommon histological subtype was micronodular (0.6% type. Lymphangiectatic, bullous, intravascular, and pyogenic granuloma like variants were frequently observed in the nodular stage of KSs. Lympangioma like changes were seen to be present in the early KS lesions. Lymphangiectatic type was oftenly associated with bullous component, whereas pyogenic granuloma like type demonstrated superficial ulceration and intense inflammatory response. Lymphangioma like and intravascular types exhibited a characteristic appearance, while other variants were accompanied by components belonging to different subtypes. Conclusion: In KS, histopathological subtypes can develop as a result of different pathological processes. The next stage of the current study, which is one of the

  15. A preliminary study of dengue infection in Brunei.

    Science.gov (United States)

    Osman, Osmali; Fong, Mun Yik; Devi, Shamala

    2007-07-01

    The purpose of this study was to examine the extent of dengue infection in Brunei and to determine the predominant serotype circulating in the country. The study generated useful epidemiological data on dengue infection in Brunei. A total of 271 samples from patients suspected of having dengue infections were selected and analyzed. All patients were seen in clinics and hospitals in Brunei. The samples were collected from April 2005 to April 2006 and transported to the WHO Collaborating Centre for Arbovirus Reference and Research, University of Malaya, Malaysia. The following tests were used to achieve the objectives: in-house IgM-capture enzyme-linked immunosorbent assay, virus isolation in mosquito albopictus cell line (C6/36), and viral RNA detection and serotyping by reverse transcriptase-polymerase chain reaction (RT-PCR). The results show that 45 people were positive for dengue-specific IgM (27 males and 18 females), while RT-PCR detected dengue viral RNA in 12 patients, 3 identified as DEN-1 and 9 as DEN-2. Dengue virus was isolated from 6 patients using the C6/36 cell line; 3 were DEN-2 isolates and 3 were DEN-1 isolates. These data show that dengue virus is circulating in Brunei and the predominant infecting serotype for that period was DEN-2 followed by DEN-1. This study is the first to report the detection and isolation of dengue virus from Brunei using RT-PCR and culture in the C6/36 albopictus mosquito cell line.

  16. A preliminary study on spatial unmasking of virtual separated sources

    Institute of Scientific and Technical Information of China (English)

    XIE ZhiWen; JIN Jing

    2008-01-01

    An experimental method with headphone virtual reproduction is proposed and a series of experiments to study forward masking effect when the masker and the masked signal are spatially separated in azimuth are conducted. Then, the masking thresholds are compared with those when the masker and the masked signal source are at the same place. The results show that, although both the thresholds of 0°and±30° sound images increase with the sound pressure level (SPL) of the masker, spatial unmasking may be really observed. The maximum unmasking is as large as 15 dB. This spatial unmasking effect is mainly attributed to better-ear con-tribution.

  17. A preliminary study on spatial unmasking of virtual separated sources

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    An experimental method with headphone virtual reproduction is proposed and a series of experiments to study forward masking effect when the masker and the masked signal are spatially separated in azimuth are conducted. Then, the masking thresholds are compared with those when the masker and the masked signal source are at the same place. The results show that, although both the thresholds of 0° and ±30° sound images increase with the sound pressure level (SPL) of the masker, spatial unmasking may be really observed. The maximum unmasking is as large as 15 dB. This spatial unmasking effect is mainly attributed to better-ear contribution.

  18. ARSENIC DEGRADATION BY Pseudomonas aeruginosa FOR WATER BIOREMEDIATION. PRELIMINARY STUDY

    Directory of Open Access Journals (Sweden)

    Esther E. Pellizzari

    2015-03-01

    Full Text Available The aim of this study was to investigate the arsenic resistance in pure cultivations of Pseudomonas aeruginosa isolated from Presidencia Roque Sáenz Peña groundwater (Chaco province, and evaluate the possibility of its use to remove arsenic from groundwater. Strains were immobilized in natural stone and cultivated in salts broth and 1 mgAs/L. The arsenic resistance and biofilm formation were observed, obtaining interaction between cells, rock and arsenic. Arsenic removal was evaluated during 3 months and its final percentage of the experiment was 60%.

  19. Preliminary Problem Definition Study on Munitions-Related Chemicals.

    Science.gov (United States)

    1979-04-01

    literature; how- S ever, Sander et al. (1975a, b) studied the effect of N-nitrosomorpholine in a series of experiments with cress plants (Lepidiwu sativum...Adenomas by Amines or Ureas Plus Nitrite and by N-Nitroso Compounds: Effect of Ascorbate, Gallic Acid, Thiocyanate, and Caffine ," j. Nat’l Cancer instit...Washington, D.C. Garber, K. (1970), "Air Pollution by Heavy-Metal-Containing Dusts. Effects on Plants ." LandAirt, Forsch, Sonderh., 25, 59-68

  20. Preliminary Clinical Study of Intra-vas Device

    Institute of Scientific and Technical Information of China (English)

    吴伟雄; 袁石锦; 陈振文; 谷翊群; 李世勤

    1994-01-01

    Fifty-one volunteers with implanted intravas device (IVD ) in comparison with 40 volunteers undergone no-scalpel vasectomy have been recruited for 1 to 3 years clinical follow-up study, The results demonstrate that efficacy rates of contraception in both the IVD group and the vasectomy group are 100%, Sixteen out of thirty - one volunteers (51.6% ) in the IVD group were found to have glucosidase activity in their seminal plasma 1 to 3 years after the operation. Only 12 subjects in the IVD

  1. Synthesis, Computational Studies and Preliminary Pharmacological Evaluation of New Arylpiperazines

    Directory of Open Access Journals (Sweden)

    Sushil Kumar

    2011-01-01

    Full Text Available A series of novel arylpiperazines were synthesized and the target compounds evaluated for atypical antipsychotic activity in apomorphine induced climbing behavior (D2 antagonism, 5-HTP induced head twitches (5-HT2A antagonism and catalepsy studies in albino mice. The physicochemical similarity of the target compounds with respect to standard drugs clozapine, ketanserine and risperidone was assessed by calculating from a set of physiochemical properties using software programs. The test compounds (3a-j demonstrated good similarity values with respect to the standard drugs. Among them, compound 3d has emerged as an important lead compound showing potential atypical antipsychotic like profile.

  2. ANAEROBIC MEMBRANE BIOREACTORS FOR DOMESTIC WASTEWATER TREATMENT. PRELIMINARY STUDY

    Directory of Open Access Journals (Sweden)

    Luisa Vera

    2014-12-01

    Full Text Available The operation of submerged anaerobic membrane bioreactors (SAnMBRs for domestic wastewaters treatment was studied in laboratory scale, with the objective to define sustainable filtration conditions of the suspensions along the process. During continuous experiments, the organic matter degradation by anaerobic way showed an average DQOT removal of 85% and 93%. Indeed, the degradation generated biogas after 12 days of operation and its relative methane composition was of 60% after 25 days of operation. Additionally, the comparison between membrane bioreactors (MBRs performance in aerobic and anaerobic conditions in filterability terms, reported that both systems behave similarly once reached the stationary state.

  3. Magnitude of relationship between burnout and absenteeism: a preliminary study.

    Science.gov (United States)

    Gil-Monte, Pedro R

    2008-04-01

    This study examined the influence of guilt related to a negative attitude toward patients and its relation with burnout and absenteeism. The sample consisted of 717 nursing professionals. Depersonalization was evaluated by the Maslach Burnout Inventory and Guilt was evaluated by one item. To estimate Absenteeism, participants were asked about the number of workdays they had missed in the past year. Hierarchical multiple regression analyses make it possible to conclude that guilt explains work absenteeism, and the interaction between depersonalization and guilt (Incr. R2 = .008, p burnout and symptoms such as absenteeism.

  4. QUALITY CONTROL PARAMETERS OF BRIHAT DASHAMULA TAILA: A PRELIMINARY STUDY

    Directory of Open Access Journals (Sweden)

    Sharma Vinay

    2011-05-01

    Full Text Available Standard analytical parameters of a number of Ayurvedic oils have been described in API. Brihat Dashamula Taila is one of the most commonly used oil by Ayurvedic Physicians. But there no standard analytical parameters are available in any authentic texts. Therefore this study aimed to set the quality control parameters with SOP of Brihat Dashamula Taila and found values like Refractive index (1.47 at 400C, specific gravity (0.923 at 250C Acid value (1.2, Iodine value (92.6 and Saponification value (86.34 may be considered as standard.

  5. Zero emission city. Preliminary study; Null-Emissions-Stadt. Sondierungsstudie

    Energy Technology Data Exchange (ETDEWEB)

    Diefenbach, N.; Enseling, A.; Werner, P.; Flade, A.; Greiff, R.; Hennings, D.; Muehlich, E.; Wullkopf, U.; Sturm, P.; Kieslich, W.; Born, R.; Grossklos, M.; Hatteh, R.; Mueller, K.; Ratschow, A.; Valouch-Fornoff, C.

    2002-10-01

    The idea of a 'zero emission city' is investigated by the Institut Wohnen und Umwelt on behalf of the Federal Minister of Education and Research. After describing the current situation and defining the key parameters of a 'zero emission city', settlement structures, power supply, production processes and transportation are analyzed and linked with the communal action level to obtain a framework for research, activities and actions. The study ends with recommendations for a research programme 'zero emission city'. (orig.) [German] Die von den Staedten der Industrielaender ausgehenden Emissionen stellen im Hinblick auf die globalen Belastungen wie z.B. Treibhauseffekt, Ozonabbau und Versauerung das Hauptproblem dar. Aus diesem Grunde bietet es sich an, den Gedanken der 'Null-Emissions-Stadt', der Vision einer moeglichst emissionsfreien Stadt, aufzugreifen und auf seine Tragfaehigkeit fuer innovative Handlungsmodelle forschungsstrategisch zu ueberpruefen. Das Bundesministerium fuer Bildung und Forschung hat das Institut Wohnen und Umwelt beauftragt, in einer Sondierungsstudie dieser Fragestellung nachzugehen. Nach der Festlegung der Ausgangsbedingungen und Eckpunkte der Vision 'Null-Emissions-Stadt' und der Analyse der vier Handlungsfelder Siedlungsstrukturen, Energieversorgung, Produktionsprozesse (Kreislaufwirtschaft) und Verkehr werden diese aufgegriffen und mit der kommunalen Handlungsebene verknuepft und zu einem Forschungs-, Handlungs- und moeglichen Aktionsrahmen zusammengefuegt. Die Studie schliesst mit Hinweisen fuer die Gestaltung eines Forschungsprogramms 'Null-Emissions-Stadt'. (orig.)

  6. Preliminary study on hydrogeology in tectonically active areas.

    Energy Technology Data Exchange (ETDEWEB)

    Lowry, Thomas Stephen; Lappin, Allen R.; Gettemy, Glen L.; Jensen, Richard Pearson; Arnold, Bill Walter; James, Scott Carlton; Lee, Moo Yul; Meier, Diane A.

    2006-09-01

    This report represents the final product of a background literature review conducted for the Nuclear Waste Management Organization of Japan (NUMO) by Sandia National Laboratories, Albuquerque, New Mexico, USA. Internationally, research of hydrological and transport processes in the context of high level waste (HLW) repository performance, has been extensive. However, most of these studies have been conducted for sites that are within tectonically stable regions. Therefore, in support of NUMO's goal of selecting a site for a HLW repository, this literature review has been conducted to assess the applicability of the output from some of these studies to the geological environment in Japan. Specifically, this review consists of two main tasks. The first was to review the major documents of the main HLW repository programs around the world to identify the most important hydrologic and transport parameters and processes relevant in each of these programs. The review was to assess the relative importance of processes and measured parameters to site characterization by interpretation of existing sensitivity analyses and expert judgment in these documents. The second task was to convene a workshop to discuss the findings of Task 1 and to prioritize hydrologic and transport parameters in the context of the geology of Japan. This report details the results and conclusions of both of these Tasks.

  7. Preliminary study: voluntary food intake in dogs during tryptophan supplementation.

    Science.gov (United States)

    Fragua, Víctor; González-Ortiz, Gemma; Villaverde, Cecilia; Hervera, Marta; Mariotti, Valentina Maria; Manteca, Xavier; Baucells, María Dolores

    2011-10-01

    Tryptophan, a precursor of important molecules such as serotonin, melatonin and niacin, is an essential amino acid for dogs. In pigs, tryptophan supplementation has been shown to induce a significant increase in food intake. The aim of the present study was to assess whether long-term tryptophan supplementation increases voluntary food intake in dogs and to observe whether this was accompanied by a change in serum ghrelin. In the present study, sixteen adult Beagle dogs were used, with four male and four female dogs fed diets supplemented with tryptophan (1 g/dog per d) during 81 d (Trp) and four male and four female dogs that were not supplemented (control). A voluntary food intake test was performed during 5 d following the supplementation period. The Trp group tended to show a higher food intake during the voluntary food intake test (58.0 (SE 5.37) v. 77.5 (SE 3.65) g/kg metabolic weight per d; P = 0.074). No significant differences were found for serum ghrelin concentrations.

  8. [Preliminary study on pollination biology of Tulipa edulis].

    Science.gov (United States)

    Wu, Zhengjun; Zhu, Zaibiao; Guo, Qiaosheng; Xu, Hongjian; Ma, Hongliang; Miao, Yuanyuan

    2012-02-01

    Current study on the pollination biology of Tulipa edulis was conducted to investigate its pollination characteristics and to provide references for artificial domestication and breeding of T. edulis. Flowering dynamics, pollinators, morphology and structure of flower were observed. Different methods were adopted to evaluate the pollen vitality, and benzidine-H2O2 method was used for estimation of the stigma receptivity. Breeding system was evaluated based on out-crossing index (OCI) , pollen-ovule ratio (P/O) and the results of emasculation, bagging and artificial pollination studies. The flower of T. edulis showed typical characteristics of Liliaceae. The pollen remained viable to some extent during all the anthesis and peaked within three days after blossoming. Stigma acceptability peaked in the first day of blossom and dwindled away in the next four days. The type of breeding system of T. edulis was facultative xenogamy, three species of Halictus are the main pollination insects. The type of breeding system of T. edulis was facultative xenogamy, withal cross-pollination give priority to self-pollination, and the insects play a main role on the pollination of T. edulis, further validation are needed to judge if the wind is helpful to pollination.

  9. Effects of vibrotactile vestibular substitution on vestibular rehabilitation - preliminary study,

    Directory of Open Access Journals (Sweden)

    Cibele Brugnera

    2015-12-01

    Full Text Available ABSTRACT INTRODUCTION: Some patients with severe impairment of body balance do not obtain adequate improvement from vestibular rehabilitation (VR. OBJECTIVE: To evaluate the effectiveness of Vertiguard(tm biofeedback equipment as a sensory substitution (SS of the vestibular system in patients who did not obtain sufficient improvement from VR. METHODS: This was a randomized prospective clinical study. Thirteen patients without satisfactory response to conventional VR were randomized into a study group (SG, which received the vibrotactile stimulus from Vertiguard(tm for ten days, and a control group (CG, which used equipment without the stimulus. For pre- and post-treatment assessment, the Sensory Organization Test (SOT protocol of the Computerized Dynamic Posturography (CDP and two scales of balance self-perception, Activities-specific Balance Confidence (ABC and Dizziness Handicap Inventory (DHI, were used. RESULTS: After treatment, only the SG showed statistically significant improvement in C5 (p = 0.007 and C6 (p = 0.01. On the ABC scale, there was a significant difference in the SG (p= 0.04. The DHI showed a significant difference in CG and SG with regard to the physical aspect, and only in the SG for the functional aspect (p = 0.04. CONCLUSION: The present findings show that sensory substitution using the vibrotactile stimulus of the Vertiguard(tm system helped with the integration of neural networks involved in maintaining posture, improving the strategies used in the recovery of body balance.

  10. A preliminary study of airborne microbial biodiversity over Peninsular Antarctica.

    Science.gov (United States)

    Hughes, K A; McCartney, H A; Lachlan-Cope, T A; Pearce, D A

    2004-07-01

    This study used PCR-based molecular biological identification techniques to examine the biodiversity of air sampled over Rothera Point (Antarctic Peninsula). 16S rDNA fragments of 132 clones were sequenced and identified to reveal a range of microorganisms, including cyanobacteria, actinomycetes, diatom plastids and other uncultivated bacterial groups. Matches for microorganisms that would be considered evidence of human contamination were not found. The closest matches for many of the sequences were from Antarctic clones already in the databases or from other cold environments. Whilst the majority of the sequences are likely to be of local origin, back trajectory calculations showed that the sampled air may have travelled over the Antarctic Peninsula immediately prior to reaching the sample site. As a result, a proportion of the detected biota may be of non-local origin. Conventional identification methods based on propagule morphology or culture are often inadequate due to poor preservation of characteristic features or loss of viability during airbome transfer. The application of molecular biological techniques in describing airbome microbial biodiversity represents a major step forward in the study of airborne biota over Antarctica and in the distribution of microorganisms and propagules in the natural environment.

  11. Sexual hormone serum levels and temporomandibular disorders. A preliminary study.

    Science.gov (United States)

    Landi, Nicola; Lombardi, Ilaria; Manfredini, Daniele; Casarosa, Elena; Biondi, Katya; Gabbanini, Massimo; Bosco, Mario

    2005-02-01

    The aim of the present study was to investigate the role of sexual hormones in a young adult population affected by articular forms of temporomandibular disorders (TMD), measuring 17beta-estradiol and progesterone serum levels. In the study, we included 40 patients (20 males and 20 females) with a Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) axis I group II diagnosis of disk displacement and/or group III diagnosis of arthralgia, osteoarthritis or osteoarhrosis, and 32 healthy controls. In female patients, blood samples were collected in follicular and luteal phases of the same menstrual cycle, while only one blood sample was drawn in male patients. Serum levels of estradiol and progesterone were determined using a radioimmunoassay and the comparison between the two groups was performed using a t test. Regarding estradiol, our results showed significantly higher serum levels in patients affected by TMD than in healthy controls, both in males (p hormones, these data suggest that high serum estrogen levels might be implicated in the physiopathology of TMD.

  12. A preliminary study of periodontitis and vascular calcification compound model

    Institute of Scientific and Technical Information of China (English)

    MENGYun; DENGJing; PanKe-qing

    2015-01-01

    Objective This experiment is desired to establish a compound model of chronic periodontitis and vascular calcification,so as to study the relation of periodontal and vascular calcification.Methods Forty male Wistar rats were randomly divided into:control group(group C),periodontitis group(group CP),vascular calcification group(group VDN),compound group (group CP+VDN).Every groups accepted the corresponding manages to establish the animal model.Eight weeks later,al the rats were sacrificed and the fol owing items were observed:inflam-matory factor in serum were tested,Hematoxylin-eosin staining(HE)staining of vascular tissue were taken to test.Results Through detection of periodontal tissue,serum and vascular tissue,an-imal models were successful.Histopathologic observation revealed:obvious inflammation of periodontal tissue was obversed in group CP and CP+VDN.The red Mineralized nodules deposition in group VDN and CP+VDN were higher than in group C and CP(P<0.05)by HE staining,and that in group CP+VDN was significantly higher than in group VDN(P<0.05);Animals in group CP+VDN showed higher level of IL-1 in serum than that in group CP,VDN and C.Conclusion This study has demonstrated that periodontitis have some promoting ef ect on vascular cal-cification.

  13. Preliminary studies on immobilization of lipase using chicken eggshell

    Science.gov (United States)

    Salleh, S.; Serri, N. A.; Hena, S.; Tajarudin, H. A.

    2016-06-01

    A few advantages of enzyme immobilization are reusability of expensive enzyme, improvement of stability and activity compared to crude enzyme. Various organic components can be used as carrier for enzyme immobilization such as chicken eggshell. It can be used as a carrier for immobilization as its mineral component mostly contains of calcium carbonate. In the present study, Tributyrin method was used to test enzyme activity of Rhizomucour Miehei, Candida Antarctica and Candida Rugosa. Rhizomucour Miehei shows the highest enzyme activity (360.8 mol/min/mL lipase) and was used in further experiment. Experiment was continued to study incubation time for lipase immobilization on eggshell (1-4 hours) and reaction time of esterification of sugar ester (0-72 hours). Two hours incubation time for lipase immobilization was observed and gives the highest yield of sugar ester (78.13%). Fructose and stearic acid as substrate was used for the production of sugar ester. The highest percentage of sugar ester production was shown at 36 hours of reaction time.

  14. Marine actinomycetes from Madeira Archipelago preliminary taxonomic studies

    Directory of Open Access Journals (Sweden)

    Ilda Santos Sanches

    2014-06-01

    Full Text Available The oceans cover 70 % of the Earth´s surface and harbor most of the planet´s biodiversity. However the microbiological component of this diversity remains relatively unexplored. Marine actinomycetes, are a robust resource of chemically prolific novelty. Producing structurally unique biological active secondary metabolites, generating a valuable source for innovative biotechnology and drug discovery[1,2]. As a consequence, the ecological role of actinomycetes and their marine ecosystems may no longer be neglected. It is crucial to move our research efforts into ocean regions for which we know little or nothing about the indigenous microbial diversity. The Portuguese Archipelago, Madeira is located in the Macaronesian Atlantic region, emerging from the African tectonic plate, found in the extreme south of the Tore-Madeira ridge, has a unique biogeography and biodiversity. These distinctive characteristics combined with the fact that Madeira have never been explored, as far as indigenous marine actinomycetes are concerned, makes it from the scientific point of view, the perfect target for our studies. From 662 marine sediment samples collected along Madeira Archipelago (Figure 1 during June of 2012, covering depths from 10-1310 m, a total of 421 actinomycete strains were isolated. In a previous study, an assemblage of 82 strains was selected for taxonomic identification, having into account representative morphological diversity characteristics of the actinomycetes, isolated from Madeira Archipelago. Based on 16S rRNA gene sequencing, it was observed that the genera Streptomyces, Micromonospora and Salinispora were predominant, 81% [3]. Additionally, in a recent study, our team selected 168 strains with Salinispora look-alike morphological features. From these 28 strains were identified as belonging to the seawater-obligate marine actinomycete genus Salinispora. Representing the first report of Salinispora spp. in the Macaronesian Atlantic Ocean

  15. Cognitive processes in criminal profile construction: a preliminary study.

    Science.gov (United States)

    Kocsis, Richard N; Middledorp, Jenny; Try, Andrew C

    2005-12-01

    This study undertook an empirically based examination of the cognitive processes associated with the accurate construction of a criminal psychological profile. This was accomplished by comparing the abilities of profilers and nonprofilers in two simulated profiling exercises that measured both profile accuracy and an individual's performance on various tests of memory and comprehension related to the case materials presented in each exercise. The results of these experiments suggest that an incremental relationship exists between comprehension of the case materials and accuracy of the profiles generated. In addition, the findings provide some tentative indications that the comprehension of case material in a narrative (i.e., written) format is an integral cognitive function to proficient profiling.

  16. Preliminary Study of Stereotactic Radiotherapy for Lung Cancer

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    From March 1997 to November 1999, 45 patients with lung cancer were treated by astereotactic radiotherapy, with 15 cases treated by a stereotactic radiotherapy alone, and 30 cases by the external radiotherapy plus stereotactic radiotherapy. The clinical target volume was 1.89-187. 26 cm3 with the median being 18. 17 cm3. The doses of plan target volume (PTV) edge was 16-30 Gy/2-3 times and the doses of center was 120 % to 150 % of PTV edge doses. The overall response rate was 84.4 % (38/45), with 11 complete response (CR) and 27 partial response (PR). This study confirmed that the stereotactic radiotherapy is a safe and effective therapy for lung cancer. For those early-stage patients who can tolerate neither operation nor even conventional radiotherapy for various reasons, it can both achieve therapeutic purpose and improve quality of life.

  17. Preliminary Exploratory Study of Different Phase II Collimators

    CERN Document Server

    Lari, L; Bertarelli, A; Bracco, C; Brugger, M; Cerutti, F; Dallocchio, Alessandro; Doyle, E; Ferrari, A; Keller, L; Lundgren, S; Markiewicz, T; Mauri, M; Roesler, S; Sarchiapone, L; Smith, J; Vlachoudis, V

    2008-01-01

    The LHC collimation system is installed and commissioned in different phases, following the natural evolution of the LHC performance. To improve cleaning efficiency towards the end of the low beta squeeze at 7TeV, and in stable physics conditions, it is foreseen to complement the 30 highly robust Phase I secondary collimators with low impedance Phase II collimators. At this stage, their design is not yet finalized. Possible options include metallic collimators, graphite jaws with a movable metallic foil, or collimators with metallic rotating jaws. As part of the evaluation of the different designs, the FLUKA Monte Carlo code is extensively used for calculating energy deposition and studying material damage and activation. This report outlines the simulation approach and defines the critical quantities involved.

  18. Preliminary Design Study for a National Digital Seismograph Network

    Science.gov (United States)

    Peterson, Jon; Hutt, Charles R.

    1981-01-01

    Introduction Recently, the National Research Council published a report by the Panel on National, Regional, and Local Seismograph Networks of the Committee on Seismology in which the principal recommendation was for the establishment of a national digital seismograph network (NDSN). The Panel Report (Bolt, 1980) addresses both the need and the scientific requirements for the new national network. The purpose of this study has been to translate the scientific requirements into an instrumentation concept for the NSDS. There are literally hundreds, perhaps thousands, of seismographs in operation within the United States. Each serves an important purpose, but most have limited objectives in time, in region, or in the types of data that are being recorded. The concept of a national network, funded and operated by the Federal Government, is based on broader objectives that include continuity of time, uniform coverage, standardization of data format and instruments, and widespread use of the data for a variety of research purposes. A national digital seismograph network will be an important data resource for many years to come; hence, its design is likely to be of interest to most seismologists. Seismologists have traditionally been involved in the development and field operation of seismic systems and thus have been familiar with both the potential value and the limitations of the data. However, in recent years of increasing technological sophistication, the development of data sstems has fallen more to system engineers, and this trend is likely to continue. One danger in this is that the engineers may misinterpret scientific objectives or subordinate them to purely technological considerations. Another risk is that the data users may misuse or misinterpret the data because they are not aware of the limitations of the data system. Perhaps the most important purpose of a design study such as this is to stimulate a dialogue between system engineers and potential data users

  19. Blackened bronchoalveolar lavage fluid in crack smokers. A preliminary study.

    Science.gov (United States)

    Greenebaum, E; Copeland, A; Grewal, R

    1993-11-01

    A retrospective study was performed on heavily pigmented pulmonary cytologic specimens from 14 hospital patients to determine the clinical features distinguishing these cases. The lavage fluid or sputum in each case was turbid and gray or black, exceeding the blackness usually seen in heavy tobacco smokers dwelling in the same urban environment. Excessive carbonaceous material was observed in the cytoplasm of pulmonary alveolar macrophages or the extracellular compartment of the smears. The latter feature is not seen in cigarette smokers. Many other pigmentary sources were ruled out, including melanin, hemosiderin, medicinal charcoal, India ink, and hematoxylin crystals. The common feature of the patients was that they recently or currently smoked the crack form of cocaine heavily; five patients also had positive toxicologic results for cocaine at admission. The authors suggest that blackened bronchoalveolar lavage fluid indicates the possibility of crack cocaine smoking and the associated sequelae, particularly when the carbonaceous material is present in the extracellular compartment.

  20. Polarization in Thermal Emission from Hot Jupiters: Preliminary Studies

    Science.gov (United States)

    Kopparla, Pushkar; Natraj, Vijay; Yung, Yuk; Spurr, Robert

    2016-10-01

    Scattering of thermal emission from a deep, hot region by high altitude atmospheric particles induces polarization in the scattered light. However, symmetries on a spherical planet with a uniform spatial distribution of scattering particles usually result in zero net polarization. If the symmetry is broken, either by rotation induced oblateness or by spatially inhomogeneous cloud or haze particle distributions, polarization may become observable. Additionally, variation of temperatures across the planetary disc could also contribute to asymmetries, giving us a new way to measure the day-night temperature contrast on hot exoplanets. We perform modeling studies using a multiple scattering, radiative transfer model for polarized light to understand how to distinguish between various symmetry breaking phenomena and map an observed polarization to a specific atmospheric state. The models can be used to predict the most suitable candidates for observation, and once observations are available, to retrieve various parameters of interest.

  1. A preliminary study of cryosphere service function and value evaluation

    Institute of Scientific and Technical Information of China (English)

    XIAO Cun-De; WANG Shi-Jin; QIN Da-He

    2015-01-01

    Cryosphere science research and development (R&D) has been strongly committed to public service, integrating natural sciences with socioeconomic impacts. Owing to the current shift from purely natural cryosphere scientific research to linking cryosphere science with so-cioeconomic and cultural science, cross-disciplinary research in this field is emerging, which advocates future cryosphere science research in this field. Utilizing the cryosphere service function (CSF), this study establishes CSF and its value evaluation system. Cryosphere service valuation can benefit the decisionmakers' and public's awareness of environmental protection. Implementing sustainable CSF utilization strategies and macroeconomic policymaking for global environmental protection will have profound and practical significance as well as avoid environmental degradation while pursuing short-term economic profits and achieving rapid economic development.

  2. Proton MR spectroscopy in neuroborreliosis: a preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Ustymowicz, A.; Tarasow, E.; Walecki, J. [Department of Radiology, Medical Academy, Bialystok (Poland); Zajkowska, J.; Hermanowska-Szpakowicz, T. [Department of Infectious Diseases and Neuroinfections, Medical Academy, Bialystok (Poland)

    2004-01-01

    We report results of a magnetic resonance spectroscopy (MRS) study in 12 patients with neuroborreliosis. We used a PRESS sequence, placing an 8 cm{sup 3} voxel in normal-appearing white matter of the frontal lobe. Peaks indicating N-acetylaspartate (NAA), choline (Cho), creatine (Cr), myo-inositol (mI), lipids (Lip) and lactate (Lac) were identified and ratios of NAA/Cr, Cho/Cr, mI/Cr, Lip/Cr, Lac/Cr calculated. Significant increases in Cho/Cr and Lip/Cr were noted. No abnormality was found in mean NAA/Cr and Lac/Cr, but in four patients there was a decreased NAA peak; mI/Cr ratio was slightly increased. Although the spectroscopic profile in patients with neuroborreliosis seems to be nonspecific, MRS might be useful for assessing tissue damage of the central nervous system. (orig.)

  3. Preliminary study of chemical compositional data from Amazon ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Toyota, Rosimeiri G.; Munita, Casimiro S.; Luz, Fabio A. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)]. E-mail: rosimeiritoy@yahoo.com.br; Neves, Eduardo G. [Museu de Arqueologia e Etnolgia, Sao Paulo, SP (Brazil)]. E-mail: egneves@usp.br; Oliveira, Paulo M.S. [Sao Paulo Univ., SP (Brazil). Escola Politecnica. Inst. de Matematica e Estatistica]. E-mail: poliver@usp.br

    2005-07-01

    Eighty seven ceramic samples from Acutuba, Lago Grande and Osvaldo archaeological sites located in the confluence of the rivers Negro and Solimoes were submitted to chemical analysis using instrumental neutron activation analysis to determine As, Ba, Ce, Co, Cr, Cs, Eu, Fe, Hf, K, La, Lu, Rb, Na, Nd, Sb, Sc, Sm, Ta, Tb, Th, Yb, Zn, and U. The database were studied using the Mahalanobis distance, and discriminant analysis. The results showed that the ceramics of each site differ from each other in chemical composition and that they form three different groups. Chemical classification of the ceramics suggests that vessels were made locally, as only ceramics from the same area show homogeneity of data. (author)

  4. Psychological Preparation for Paralympic Athletes: A Preliminary Study.

    Science.gov (United States)

    Blumenstein, Boris; Orbach, Iris

    2015-07-01

    Since the first Paralympics in 1960 there has been an increase in social and scientific interest in Paralympic athletes' personality, their preparation, and their sport results. During the last 20 yr, researchers and practitioners have been focused on psychological-skills programs for athletes with disabilities. The purpose of this article was to describe a psychological-preparation program for Israeli Paralympic athletes. Two subprograms, the learning-modification-application approach and the Simulation Training Exercise Program, were adapted to athletes' disability and sport demands. Two case studies, from table tennis and sailing (Sonar 3-person keelboat), are described to demonstrate how systematic sport psychology preparation can be effectively integrated into the training process of Paralympic athletes. Some recommendations for Paralympic athletes are presented.

  5. Preliminary study on radiocarbon AMS dating of pollen

    Institute of Scientific and Technical Information of China (English)

    周卫建; 周杰; 萧家仪; D.Donahue; A.J.T.Jull

    1999-01-01

    17 samples were collected from aeolian and lacustrine profiles within the environment sensitive zone of the Loess Plateau, and an experimental method was established which is suitable for pollen extraction from aeolian sediment. A comparative study of pollen dating was carried out using the accelerator mass spectrometry (AMS) 14C dating of known age samples, and then an experiment with the pollen concentrates was performed. The results indicate that pollen that has been deposited simultaneously with sediment in a stable environment can provide reliable ages. This technique will provide a way of improving the chronological framework for the Loess Plateau since the late Pleistocene. The 14C dating was combined with field investigations, and from the geological record within this zone, evidence was extracted of four major monsoon precipitation changes during the transition from the late Pleistocene to Holoeene.

  6. A Preliminary Study of Surface Temperature Cold Bias in COAMPS

    Energy Technology Data Exchange (ETDEWEB)

    Chin, H-N S; Leach, M J; Sugiyama, G A; Aluzzi, F J

    2001-04-27

    It is well recognized that the model predictability is more or less hampered by the imperfect representations of atmospheric state and model physics. Therefore, it is a common problem for any numerical models to exhibit some sorts of biases in the prediction. In this study, the emphasis is focused on the cold bias of surface temperature forecast in Naval Research Laboratory's three-dimensional mesoscale model, COAMPS (Coupled Ocean/Atmosphere Mesoscale Prediction System). Based on the comparison with the ground station data, there were two types of ground temperature cold biases identified in LLNL (Lawrence Livermore National Laboratory) operational forecasts of COAMPS over the California and Nevada regions during the 1999 winter and the 2000 spring. The first type of cold bias appears at high elevation regions covered by snow, and its magnitude can be as large as 30 F - 40 F lower than observed. The second type of cold bias mainly exists in the snow-free clear-sky regions, where the surface temperature is above the freezing point, and its magnitude can be up to 5 F - 10 F lower than observed. These cold biases can affect the low-level stratification, and even the diurnal variation of winds in the mountain regions, and therefore impact the atmospheric dispersion forecast. The main objective of this study is to explore the causes of such cold bias, and to further the improvement of the forecast performance in COAMPS. A series of experiments are performed to gauge the sensitivity of the model forecast due to the physics changes and large-scale data with various horizontal and vertical resolutions.

  7. Self-acceptance of stuttering: A preliminary study.

    Science.gov (United States)

    De Nardo, Thales; Gabel, Rodney M; Tetnowski, John A; Swartz, Eric R

    2016-01-01

    This study explored the relationship between self-acceptance of stuttering and (1) psychosocial factors (self-esteem, hostility towards others, emotional support, and perceived discrimination); (2) treatment history (support group participation, therapy duration, and perceived therapy success); and (3) previously reported variables in self-acceptance of stuttering, which include age and stuttering severity. Participants were 80 adults who stutter who were recruited with assistance from the National Stuttering Association and Board Certified Specialists in Fluency Disorders. Participants completed an electronic survey composed of an acceptance of stuttering scale, psychosocial scales, and a participant information questionnaire. Statistical analysis identified significant correlations between participants' reports of self-acceptance of stuttering and self-esteem, perceived discrimination, hostility towards others, and perceived therapy outcome. Self-esteem was positively correlated with self-acceptance, while hostility towards others and perceived discrimination was negatively correlated with self-acceptance. Participants who perceived their therapy outcome to be successful were significantly more likely to report higher levels of self-acceptance. No significant relationships were found between self-acceptance of stuttering and support group participation, emotional support, stuttering severity, and participant age. This exploratory investigation has provided a foundation for future studies on the self-acceptance of stuttering. The findings indicate common psychosocial variables in self-acceptance of stuttering and of other disabilities. The significant relationships between self-acceptance of stuttering and psychosocial and therapeutic variables found need to be further explored to identify its causalities and clinical implications. The reader will be able to (1) discuss the importance of assessing self-acceptance of stuttering, (2) summarize the literature on self

  8. Weight loss and P wave dispersion: a preliminary study.

    Science.gov (United States)

    Falchi, Anna Giulia; Grecchi, Ilaria; Muggia, Chiara; Tinelli, Carmine

    2014-01-01

    The aim of this study is to investigate if therapeutic weight loss reduces P wave dispersion. 20 obese patients (10 males and 10 females), part of a randomized clinical trial, were examined over a 6 month period. They were treated with a diet, aiming at 5% weight loss at the 6th month. After physical examination, they underwent laboratory tests, bioelectrical impedance analysis and a electrocardiogram (ECG). ECGs were transferred to a personal computer via a scanner and then magnified 400 times. We examined at baseline and at the 6th month, maximum and minimum P-wave duration, P-wave dispersion and heart rate. Comparing responders (patients who lost 5% of weight at t6) and not responders (who lost less than 5%), responders showed a significant reduction of P wave dispersion value (-0.38 [SD: 0.35] mm equal to -32.3 [SD: 11.3] % p=0.00001). All responders present a reduction of P wave dispersion, while for not-responders this is no longer evident. Finally, a good degree of correlation (r=0.54) between P wave dispersion difference and the decrease of weight was noticed. Females have a better response in P dispersion reduction strictly connected with their weight loss with a good correlation, (r=0.7, p=0.002), versus a moderate correlation evidenced in males (r=0.5, p=0.011). P wave duration and dispersion are significantly reduced in patients who lost more than 5% of weight and this decrease is highly related to the extent of weight loss. Copyright © 2014 Asian Oceanian Association for the Study of Obesity. Published by Elsevier Ltd. All rights reserved.

  9. Preliminary acute toxicity study on imidacloprid in Swiss albino mice

    Directory of Open Access Journals (Sweden)

    Preeti Bagri

    2013-12-01

    Full Text Available Aim: To ascertain the maximum tolerated dose (MTD and to investigate the acute oral toxic effects of imidacloprid towards Swiss albino male mice.Materials and Methods: The MTD of imidacloprid was determined in pilot dose range finding study following the standard method. Animals were observed for toxic signs and symptoms after oral administration of MTD of imidacloprid in single dose. The body weights of animals were recorded on alternate day. Animals were sacrificed on 14th day and changes in hematological parameters (Hb, TEC, TLC and DLC and morphometric measurements (length, breadth, thickness and weight of various body organs (heart, liver, spleen, kidney, testis and epididymis were examined. The student's t-test was applied to statistically analyze the results.Results: The MTD of imidacloprid was determined to be 110 mg/kg body weight. The sign and symptoms of acute toxicity were ataxia, rigidity and fasciculation of muscles, protrusion of eye ball and tremors of head. Imidacloprid treatment resulted in decreased body weight gain as compared to the control group. The changes in hematological parameters were not significant between imidacloprid treated and control groups. Also the values of relative organ weights and morphometric measurements of various body organs did not differ significantly between the control and imidacloprid treated animals.Conclusions: MTD of imidacloprid in Swiss albino male mice through oral route was determined for the first time. Study revealed a non-toxic effect of imidacloprid on body weight, relative organs weight, hematological parameters and morphometric measurements of various body organs in mice.

  10. Wind energy in electric power production, preliminary study

    Science.gov (United States)

    Lento, R.; Peltola, E.

    1984-01-01

    The wind speed conditions in Finland have been studied with the aid of the existing statistics of the Finnish Meteorological Institute. With the aid of the statistics estimates on the available wind energy were also made. Eight hundred wind power plants, 1.5 MW each, on the windiest west coast would produce about 2 TWh energy per year. Far more information on the temporal, geographical and vertical distribution of the wind speed than the present statistics included is needed when the available wind energy is estimated, when wind power plants are dimensioned optimally, and when suitable locations are chosen for them. The investment costs of a wind power plant increase when the height of the tower or the diameter of the rotor is increased, but the energy production increases, too. Thus, overdimensioning the wind power plant in view of energy needs or the wind conditions caused extra costs. The cost of energy produced by wind power can not yet compete with conventional energy, but the situation changes to the advantage of wind energy, if the real price of the plants decreases (among other things due to large series production and increasing experience), or if the real price of fuels rises. The inconvinience on the environment caused by the wind power plants is considered insignificant. The noise caused by the plant attenuates rapidly with distance. No harmful effects to birds and other animals caused by the wind power plants have been observed in the studies made abroad. Parts of the plant getting loose during an accident, or ice forming on the blades are estimated to fly even from a large plant only a few hundred meters.

  11. Oxidative damage in young alcohol drinkers: A preliminary study.

    Science.gov (United States)

    Rendón-Ramírez, Adela; Cortés-Couto, Miriam; Martínez-Rizo, Abril Bernardette; Muñiz-Hernández, Saé; Velázquez-Fernández, Jesús Bernardino

    2013-11-01

    Oxidative damage (OD) biomarkers have been used to evaluate metabolic stress undergone by alcoholic individuals. In alcoholic patients, these biomarkers are usually measured at late stages, i.e., when the alcoholic patients are showing clear signs of impaired hepatic function. OD biomarkers are sensitive indicators of impaired metabolic function, and might be useful in early stages of alcohol consumption to identify individuals who are at greater risk of damage in later stages of alcohol consumption. The aim of the present work was to evaluate some OD biomarkers in young people at early stages of alcohol consumption. The study was carried out in a group of young people (18-23 years old) who drank alcohol, Youngsters Exposed to Alcohol (YEA) with an average intake of 118 g of ethanol/week, and a control group (CG) of non-drinkers. Blood counts, alcohol dehydrogenase (ADH) activity, glutathione peroxidase (GSH-Px) activity, oxidative damage to DNA, and lipid peroxidation were determined in both groups. The anthropometric and blood parameters of both groups were similar and no clinical symptoms of hepatic damage were observed. Nevertheless, ADH activity, lipid peroxidation, and percentage of damaged DNA cells were higher in the YEA group than in the control group. In contrast, GSH-Px activity was lower in the YEA group than in the control group. Alteration in OD biomarkers can be found in individuals with 4-5 years of alcohol drinking history. To our knowledge, this is the first study giving evidence of OD in individuals at early stages of alcohol abuse. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. Focal neuropathies following percutaneous nephrolithotomy (PCNL)--preliminary study.

    Science.gov (United States)

    Nasseh, Hamidreza; Pourreza, Farshid; Saberi, Alia; Kazemnejad, Ehsan; Kalantari, Behnam Behmardi; Falahatkar, Siavash

    2013-01-01

    Einleitung: Postoperative neurologische Komplikationen bei operativem Eingriff an Becken und Niere sind ein bekanntes klinisches Problem und deren Krankheitsverläufe sind wichtig. Wir planten diese Studie, um die Prävalenz und die Risikofaktoren derartiger Komplikationen nach perkutaner Nephrolithotomie (PCNL) zu erfassen.Material und Methoden: Von Februar bis Juli 2011 wurde eine Querschnittstudie an 68 PCNL-Fällen durchgeführt. Die demographischen Daten und die Operationsberichte wurden ausgewertet und umfassende neurologische und körperliche Untersuchungen wurden vor und nach dem chirurgischen Eingriff vorgenommen. Die Daten wurden mit der Software SPSS 18 analysiert.Ergebnisse: In die Studie einbezogen wurden 30 männliche (46,2%) und 35 (53,8%) weibliche Patienten mit einem mittleren Alter von 47,9 ± 11,47 Jahren. Bei 8 Patienten (12,31%), bei 4 Männern und 4 Frauen, wurden im Bereich des interkostalen und lumbosakralen Plexus sensorische neurologische Komplikationen gefunden. Die am häufigsten betroffenen Dermatome und Nerven waren im Bereich T 12 (8 Fälle). Es gab eine signifikante Korrelation zwischen der Dauer des chirurgischen Eingriffes und dem Vorkommen von sensorischen Komplikationen (p<0,010). Der höchste Abfall der Hämoglobinkonzentration nach dem chirurgischen Eingriff trat bei Patienten mit neurologischen Komplikationen auf (p<0,001). Es gab keine Korrelation zwischen Alter, gewähltem Zugang, Diabetes mellitus, BMI, Bluthochdruck, Lagerung der Patienten und Ort des chirurgischen Eingriffs und den beobachteten sensorischen neurologischen Komplikationen.Schlussfolgerung: Verlängerte Dauer der PCNL und erhöhter Abfall der Hämoglobinkonzentration können zu einem erhöhten Risiko für einer Neuropathie führen. Größere prospektive Studien mit retroperitonealen bildgebenden Untersuchungen und mit Verlaufskontrollen bei den Patienten werden vorgeschlagen, um diese Komplikation besser zu verstehen.

  13. Preliminary studies of Brazilian wood using different radioisotopic sources

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Gilberto; Silva, Leonardo Gondim de Andrade e, E-mail: gcarval@ipen.br, E-mail: ftgasilva@gmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    Due to availability and particular features, wood was one of the first materials used by mankind with a wide variety of applications. It can be used as raw material for paper and cellulose manufacturing; in industries such as chemical, naval, furniture, sports goods, toys, and musical instrument; in building construction and in the distribution of electric energy. Wood has been widely researched; therefore, wood researchers know that several aspects such as temperature, latitude, longitude, altitude, sunlight, soil, and rainfall index interfere with the growth of trees. This behavior explains why average physical-chemical properties are important when wood is studied. The majority of researchers consider density to be the most important wood property because of its straight relationship with the physical and mechanical properties of wood. There are three types of wood density: basic, apparent and green. The apparent density was used here at 12% of moisture content. In this study, four different types of wood were used: 'freijo', 'jequetiba', 'muiracatiara' and 'ipe'. For wood density determination by non-conventional method, Am-241, Ba-133 and Cs-137 radioisotopic sources; a NaI scintillation detector and a counter were used. The results demonstrated this technique to be quick and accurate. By considering the nuclear parameters obtained as half value layers and linear absorption coefficients, Cs-137 radioisotopic source demonstrated to be the best option to be used for inspection of the physical integrity of electric wooden poles and live trees for future works. (author)

  14. Preliminary Study on Causative Factors Leading to Construction Cost Overrun

    Directory of Open Access Journals (Sweden)

    Aftab Hameed Memon

    2011-07-01

    Full Text Available Cost is the fundamental component for any construction project. However, cost overrun is observed as one of the most frequently occurring issues in construction projects worldwide and need to be studied more to alleviate this issue in the future. This trend is more severe in developing countries where these overruns sometimes exceeds 100% of the anticipated cost of the project.   Like other countries, construction industry in Malaysia is also facing a lot of challenges such as the delay to complete the project in time, the expenditure exceeding the budget, the building defects and over dependent of foreign workers. The ultimate effects of project delay also results in exceeding cost. This leads to serious need of addressing the critical issue of construction cost overrun. To avoid construction cost overrun, very first and most important step is to identify and understand the causes and factors responsible for that. Hence, this paper is aimed to identify various factors responsible for construction cost overrun. Through a comprehensive study of literature review, common factors causing cost overrun resulting in identification of 78 factors were mapped in frequency table. A questionnaire survey and interviews were carried out amongst selected experienced personnel for expert opinion to identify the significant factors causing cost overrun in Malaysia. Five respondents were selected from each of the respondents groups including client, consultant and contractor. The questionnaire responses were analyzed by average index method, which resulted in identification of 59 common factors causing construction cost overrun in Malaysia. Results show that poor design & delays in Design, unrealistic contract duration & requirements imposed, lack of experience, late delivery of materials & equipment, relationship between management & labour, delay preparation & approval of drawings, inadequate planning & scheduling, poor site management & supervision and

  15. Transient galactic cosmic ray modulation during solar cycle 24: A comparative study of two prominent Forbush decrease events

    Science.gov (United States)

    Lingling, Zhao; Huai, Zhang; Hongqing, He

    2016-04-01

    Forbush decrease (FD) events are of great interest for transient galactic cosmic ray modulation study. In this study, we perform statistical analysis of two prominent Forbush events during cycle 24, occurred on 8 March 2012 (Event 1) and 22 June 2015 (Event 2), respectively, utilizing the measurements from the worldwide neutron monitor (NM) network. Despite of their comparable magnitudes, the two Forbush events are distinctly different in terms of evolving GCR energy spectrum and energy dependence of the recovery time. The recovery time of Event 1 is strongly dependent on the median energy, compared to the nearly constant recovery time of Event 2 over the studied energy range. Additionally, while the evolution of the energy spectra during the two FD event exhibit similar variation pattern, the spectrum of Event 2 is very harder, especially at the time of deepest depression. These difference are essentially related to their associated solar wind disturbances. Event 1 is associated with a complicated shock-associated ICME structure of IP/Sheath/MC sequence with large radial extend and limited longitudinal extent (narrow and thick), probably merged from multiple shocks and transient flows. Conversely, Event 2 is accompanied by a relatively simple interplanetary disturbance of IP/Sheath/Ejecta sequence with small radial extend and wide longitudinal departure (wide and thin), possibly evolved from an over expanded CME. Such comparative study may help to clarify the occurrence mechanisms of Forbush events related to different types solar wind structures and provide valuable insight into the transient GCR modulation, especially during the unusual solar cycle 24.

  16. Preliminary study of application of Moringa oleifera resin as polymer electrolyte in DSSC solar cells

    Science.gov (United States)

    Saehana, Sahrul; Darsikin, Muslimin

    2016-04-01

    This study reports the preliminary study of application of Moringa oleifera resin as polymer electrolyte in dye-sensitized solar cell (DSSC). We found that polymer electrolyte membrane was formed by using solution casting methods. It is observed that polymer electrolyte was in elastic form and it is very potential to application as DSSC component. Performance of DSSC which employing Moringa oleifera resin was also observed and photovoltaic effect was found.

  17. Preliminary study of a wing-tip vortex using laser velocimetry

    Science.gov (United States)

    Takahashi, R. K.; Mcalister, K. W.

    1987-01-01

    Measurements have been made in the wake of a semi-span NACA 0015 airfoil with emphasis on the region of the wing tip vortex. The spanwise and streamwise velocity components were measured using a two-component laser Doppler velocimeter. The purpose of the study was to initiate the operation of a laser velocimeter system and to perform preliminary wake measurements in preparation for a more extensive study of the structure and near field development of a tip vortex.

  18. What is cholera?:A preliminary study on caretakers' knowledge in Bangladesh

    OpenAIRE

    Tamason, Charlotte Crim; Tulsiani, Suhella; Siddique, A.; Hoque, Bilqis Amin; Jensen, Peter Kjær Mackie

    2016-01-01

    Background: Cholera has afflicted the Indian sub-continent for centuries, predominantly in West Bengal and modern-day Bangladesh. This preliminary study aims to understand the current level of knowledge of cholera in female Bangladeshi caretakers, which is important in the outcome of the disease and its spread. A pilot study was conducted among 85 women in Bangladesh using qualitative questionnaires to explore the ability of female caretakers in identifying cholera and its transmission.Findin...

  19. Journal of Island Studies: preliminary ideas from 1991, and comments from 2015

    Directory of Open Access Journals (Sweden)

    Russell King

    2015-05-01

    Full Text Available Some preliminary thoughts were penned in 1991, on the founding of an academic journal devoted to the study of the world’s islands. This collated contribution is an opportunity to look back critically at what was advised then, and what has actually come to pass through Island Studies Journal. Russell King’s prescient report from 1991 is followed by a series of candid reflections by members of ISJ’s International Editorial Board.

  20. Assessing internet addiction using the parsimonious internet addiction components model—A preliminary study.

    OpenAIRE

    Kuss, D.J.; Shorter, G. W.; Rooij, A.J. van; Griffiths, M.D.; Schoenmakers, T.M.

    2014-01-01

    Internet usage has grown exponentially over the last decade. Research indicates that excessive Internet use can lead to symptoms associated with addiction. To date, assessment of potential Internet addiction has varied regarding populations studied and instruments used, making reliable prevalence estimations difficult. To overcome the present problems a preliminary study was conducted testing a parsimonious Internet addiction components model based on Griffiths’ addiction components (Journal ...

  1. Assessing Internet addiction using the parsimonious Internet addiction components model - a preliminary study [forthcoming

    OpenAIRE

    Kuss, DJ; Shorter, GW; Van Rooij, AJ; Griffiths, MD; Schoenmakers, T.

    2014-01-01

    Internet usage has grown exponentially over the last decade. Research indicates that excessive Internet use can lead to symptoms associated with addiction. To date, assessment of potential Internet addiction has varied regarding populations studied and instruments used, making reliable prevalence estimations difficult. To overcome the present problems a preliminary study was conducted testing a parsimonious Internet addiction components model based on Griffiths’ addiction components (2005), i...

  2. Population-based study of ABCD2 score, carotid stenosis, and atrial fibrillation for early stroke prediction after transient ischemic attack: the North Dublin TIA study.

    LENUS (Irish Health Repository)

    Sheehan, Orla C

    2010-05-01

    Transient ischemic attack (TIA) etiologic data and the ABCD(2) score may improve early stroke risk prediction, but studies are required in population-based cohorts. We investigated the external validity of the ABCD(2) score, carotid stenosis, and atrial fibrillation for prediction of early recurrent stroke after TIA.

  3. Preliminary study of malaria incidence in Nouakchott, Mauritania.

    Science.gov (United States)

    Lekweiry, Khadijetou Mint; Abdallahi, Mohamed Ould; Ba, Hâmpaté; Arnathau, Céline; Durand, Patrick; Trape, Jean-François; Salem, Ali Ould Mohamed

    2009-05-05

    Malaria is one of the main motives for outpatient consultation and hospitalization in Mauritania. However, its incidence remains unclear because of diagnostic problems and insufficient epidemiological data. Between April and August 2007, a study on malaria incidence was carried out in Nouakchott city. A total of 237 febrile outpatients, from all Nouakchott districts, attending the two main hospitals of the city were investigated. Finger prick and blood dried filter paper samples were performed to prepare thick and thin films and nested-PCR for malaria parasite species identification and density. The accuracy of diagnosis of 'presumptive malaria', assigned by clinicians and based on fever and other malaria suggestive symptoms, was assessed. Entomological investigations based on morphological and molecular characterization of Anopheline species were conducted in Dar Naïm district. Malaria prevalence rate was 25.7% (61/237), the majority of positive blood slides as well as nested-PCR products were due to Plasmodium vivax 70.5% (43/61) and Plasmodium ovale 24.6% (15/61). Two malaria patients, both with P. vivax, have never travelled out of Nouakchott and seem likely to have been autochthonous (3.3%). Of the 237 individuals included in the survey, 231(97.5%) were clinically diagnosed and treated as malaria cases. 26.4% of clinically diagnosed cases were positive for Plasmodium using microscopic examination and PCR. Thus, false positive cases constituted 73.6% (170/231) of the clinically diagnosed malaria cases. The search for mosquito vectors in Dar Naïm district allowed morphological and molecular identification of Anopheles arabiensis and Anopheles pharoensis. This study demonstrates that, during the hot and dry season, Plasmodium species responsible of recurrent malaria (P. vivax and P. ovale) are the dominant species in Nouakchott city and autochthonous malaria cases exist but are rare. Clinical diagnosis of malaria has a very low positive predicted value. The

  4. Preliminary study of malaria incidence in Nouakchott, Mauritania

    Directory of Open Access Journals (Sweden)

    Trape Jean-François

    2009-05-01

    Full Text Available Abstract Background Malaria is one of the main motives for outpatient consultation and hospitalization in Mauritania. However, its incidence remains unclear because of diagnostic problems and insufficient epidemiological data. Methods Between April and August 2007, a study on malaria incidence was carried out in Nouakchott city. A total of 237 febrile outpatients, from all Nouakchott districts, attending the two main hospitals of the city were investigated. Finger prick and blood dried filter paper samples were performed to prepare thick and thin films and nested-PCR for malaria parasite species identification and density. The accuracy of diagnosis of 'presumptive malaria', assigned by clinicians and based on fever and other malaria suggestive symptoms, was assessed. Entomological investigations based on morphological and molecular characterization of Anopheline species were conducted in Dar Naïm district. Results Malaria prevalence rate was 25.7% (61/237, the majority of positive blood slides as well as nested-PCR products were due to Plasmodium vivax 70.5% (43/61 and Plasmodium ovale 24.6% (15/61. Two malaria patients, both with P. vivax, have never travelled out of Nouakchott and seem likely to have been autochthonous (3.3%. Of the 237 individuals included in the survey, 231(97.5% were clinically diagnosed and treated as malaria cases. 26.4% of clinically diagnosed cases were positive for Plasmodium using microscopic examination and PCR. Thus, false positive cases constituted 73.6% (170/231 of the clinically diagnosed malaria cases. The search for mosquito vectors in Dar Naïm district allowed morphological and molecular identification of Anopheles arabiensis and Anopheles pharoensis. Conclusion This study demonstrates that, during the hot and dry season, Plasmodium species responsible of recurrent malaria (P. vivax and P. ovale are the dominant species in Nouakchott city and autochthonous malaria cases exist but are rare. Clinical diagnosis

  5. Preliminary Hydrogeologic Characterization Results from the Wallula Basalt Pilot Study

    Energy Technology Data Exchange (ETDEWEB)

    B.P. McGrail; E. C. Sullivan; F. A. Spane; D. H. Bacon; G. Hund; P. D. Thorne; C. J. Thompson; S. P. Reidel; F. S. Colwell

    2009-12-01

    The DOE's Big Sky Regional Carbon Sequestration Partnership has completed drilling the first continental flood basalt sequestration pilot borehole to a total depth (TD) of 4,110 feet on the Boise White Paper Mill property at Wallula, Washington. Site suitability was assessed prior to drilling by the 2007-2008 acquisition, processing and analysis of a four-mile, five-line three component seismic swath, which was processed as a single data-dense line. Analysis of the seismic survey data indicated a composite basalt formation thickness of {approx}8,000 feet and absence of major geologic structures (i.e., faults) along the line imaged by the seismic swath. Drilling of Wallula pilot borehole was initiated on January 13, 2009 and reached TD on April 6, 2009. Based on characterization results obtained during drilling, three basalt breccia zones were identified between the depth interval of 2,716 and 2,910 feet, as being suitable injection reservoir for a subsequent CO2 injection pilot study. The targeted injection reservoir lies stratigraphically below the massive Umtanum Member of the Grande Ronde Basalt, whose flow-interior section possesses regionally recognized low-permeability characteristics. The identified composite injection zone reservoir provides a unique and attractive opportunity to scientifically study the reservoir behavior of three inter-connected reservoir intervals below primary and secondary caprock confining zones. Drill cuttings, wireline geophysical logs, and 31one-inch diameter rotary sidewall cores provided geologic data for characterization of rock properties. XRF analyses of selected rock samples provided geochemical characterizations of the rocks and stratigraphic control for the basalt flows encountered by the Wallula pilot borehole. Based on the geochemical results, the pilot borehole was terminated in the Wapshilla Ridge 1 flow of the Grande Ronde Basalt Formation. Detailed hydrologic test characterizations of 12 basalt interflow

  6. Clinoptilolite for Treatment of Dyslipidemia: Preliminary Efficacy Study.

    Science.gov (United States)

    Cutovic, Milisav; Lazovic, Milica; Vukovic-Dejanovic, Vesna; Nikolic, Dejan; Petronic-Markovic, Ivana; Cirovic, Dragana

    2017-09-01

    A tribomechanically activated clinoptilolite (natural aluminosilicate mineral) has been used to increase growth in meat-producing animals, as an adjuvant in cancer therapy, and a heavy metal remover in humans. Because of its unique cation exchanging and chelating properties, we hypothesized that clinoptilolite may be beneficial for the treatment of dyslipidemia in the manner similar to bile acid sequestrants. Thus, specific aims of this pilot study were to orally administer clinoptilolite in different doses and granule size combinations to determine magnitude and time profile of changes in blood lipids. A phase I/IIa prospective, open-label, uncontrolled, dose/granule size-ranging study (treatment phase 8 weeks, follow-up 6 weeks). Blood lipids were examined every 2 weeks. Outpatient clinic of a university-affiliated hospital. Forty-one subjects (all white, mean age 57.6 ± 6.8 years, 17 women) with blood lipids above the normative limits divided into three groups. A tribomechanically activated clinoptilolite was administered in three dose/grind combinations: 6 g/day of fine grind (6gF), 6 g/day of coarse grind (6gC), and 9 g/day of coarse grind (9gC). Blood concentrations of total cholesterol (TC), low-density lipoprotein cholesterol (LDLc), high-density lipoprotein cholesterol (HDLc), and triglycerides (TG). For the 3 groups combined, all lipid fractions significantly improved after 8 weeks of treatment (20-25%, p < 0.001), which reversed to baseline after 6 weeks of clinoptilolite withdrawal. Early (week 2) and the most pronounced decrease in TC and LDLc was observed in the 6gF group (19% and 23% in week 8, respectively), with no difference in HDLc and TG between the three dose/grind groups. No side effects were reported. These pilot results suggest that oral administration of clinoptilolite may improve lipid profile in individuals with dyslipidemia, which warrants further investigations.

  7. Robotic consolle for ocular surgery: a preliminary study

    Science.gov (United States)

    Rossi, Francesca; Pini, Roberto; Menabuoni, Luca; Lenzetti, Ivo; Russo, Sheila; Menciassi, Arianna; Fortuna, Damiano

    2014-02-01

    Minimally invasive surgery has recently been improved by the use of robot-assisted procedures in several medical fields. Among the ocular surgeries there are a few examples of sophisticated vitreoretinal procedures, while robotic-assisted surgery of the anterior eye segment is still under study. In this paper we propose a new approach to the robotic assisted ocular surgery: a CO2 laser system is equipped with a micromanipulator and scanner, and it is proposed to induce photothermal effects for the removal of neoformations. A sensorized tool is connected to the patient eye and to the robotic arm. This tool is equipped with force and position sensors: by the use of the spatial information from the robotic console and from the patient it is possible to control the position of the target itself and to block it in the correct position for performing surgery. The system is provided by a feedback alarm that remove the block of the patient head in any moment. The optimized robotic consolle can be used in performing scleral cuts and in the treatment of pterigium or neoformations.

  8. Preliminary studies on hoof characteristics in Amiata donkey

    Directory of Open Access Journals (Sweden)

    Alessandro Giorgetti

    2012-01-01

    Full Text Available In this work the biometrical, physical and chemical characteristics of Amiata donkey hoof were studied. The Amiata donkey is a local endangered breed and derives from the homonym mountain in Tuscany. This donkey, which was once used as pack animal in farms and in mines, is now involved in trekking, onotherapy and milk production. The mean hoof biometrics and its standard deviation were calculated. The physical and chemical characteristics were also estimated, through ANOVA, considering the hoof region as fixed effect: wall, white line and sole for hardness, wall and sole for chemical characteristics. The small size and healthy hoof, was basically cylindrical (crown cir./Foot plantar circ. ratio=0.9 and it showed higher hardness in wall (H=126.5± 3.3, followed by sole (H=105.2±3.3, and white line (H=74.0±3.3. The wall has shown the lower moisture content (%=11.7±3.2 and the higher content in Al, Mn, Li, Ni, Pb, Se. The positive correlation between Al, Li, Pb and Hardness has shown the hoof high resistence to toxic elements. Very interesting has seemed the negative correlation between K vs Li and Pb, to indicate the tendency of K to remove potentially harmful elements.

  9. PRELIMINARY STUDIES OF RIVETED JOINTS AT FEED FORCE

    Directory of Open Access Journals (Sweden)

    Radosław Bielawski

    2015-08-01

    Full Text Available The aim of the study was to determine the feasibility of riveted joints in composites materials. Static tensile test method was used. In the test one type of glass fabric was used (Interglas 92140 from which two types of composite samples were prepared. In each sample the same type of fiber with the same fiber orientation – 3 layers - was used. The samples had dimensions of 100×100 mm and thickness of approximately 1 mm. The composite probes were located in a metal frame with a screw connection which was made of screws with nominal thread pitch M5. Screws were tightened with constant torque. It was to provide an axial force to the sample during the tensile test. The frame was placed between cross-bars of tensile machine INSTRON 8516. The samples were stretched at a speed of 0.05 mm/s at a distance up to 16 mm. During the tensile test displacement of the samples and pull force were registered. Depending on the fibre orientations and the value of feed force, damage models were described. On the basis of the results the possibility of usage of aluminium rivet nuts connections in composite materials was determined.

  10. A preliminary study on dead geostationary satellite removal

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The collision between satellites IRIDIUM 33 and COSMOS 2251 indicated that the clash of two on-orbit satellites was becoming an inevitable reality. Our calculation with the two-line orbit element by NORAD showed that some two geostationary satellites had approached very close in July 2009. Therefore, more attention should be given to avoid such collisions. This paper analyzes the orbital long-term variation of a dead satellite drifting in the geostationary orbit. Also, the negative effects posed by dead satellites upon the on-orbit operational geostationary satellites are studied. Then the paper proposes a novel idea to launch a satellite sweeper whose purpose is to collect the on-orbit dead satellites and help them de-orbit to a "graveyard". The satellite sweeper consists of a parent satellite and a child satellite. The child satellite collects a dead satellite and transfers it to a higher orbit. The parent satellite stationed in the geostationary orbit is in charge of refueling the child satellite. The strategy of maneuver and rendezvous is presented and a series of formulas are derived. The analysis results show that our method to clean the geostationary orbital zone is practical and fuel-saving. With the help of just a few satellite sweepers, we can gain a clean environment of geostationary orbit environment again.

  11. Preliminary Study for Designing a Novel Vein-Visualizing Device

    Directory of Open Access Journals (Sweden)

    Donghoon Kim

    2017-02-01

    Full Text Available Venipuncture is an important health diagnosis process. Although venipuncture is one of the most commonly performed procedures in medical environments, locating the veins of infants, obese, anemic, or colored patients is still an arduous task even for skilled practitioners. To solve this problem, several devices using infrared light have recently become commercially available. However, such devices for venipuncture share a common drawback, especially when visualizing deep veins or veins of a thick part of the body like the cubital fossa. This paper proposes a new vein-visualizing device applying a new penetration method using near-infrared (NIR light. The light module is attached directly on to the declared area of the skin. Then, NIR beam is rayed from two sides of the light module to the vein with a specific angle. This gives a penetration effect. In addition, through an image processing procedure, the vein structure is enhanced to show it more accurately. Through a phantom study, the most effective penetration angle of the NIR module is decided. Additionally, the feasibility of the device is verified through experiments in vivo. The prototype allows us to visualize the vein patterns of thicker body parts, such as arms.

  12. Preliminary Study for Designing a Novel Vein-Visualizing Device.

    Science.gov (United States)

    Kim, Donghoon; Kim, Yujin; Yoon, Siyeop; Lee, Deukhee

    2017-02-07

    Venipuncture is an important health diagnosis process. Although venipuncture is one of the most commonly performed procedures in medical environments, locating the veins of infants, obese, anemic, or colored patients is still an arduous task even for skilled practitioners. To solve this problem, several devices using infrared light have recently become commercially available. However, such devices for venipuncture share a common drawback, especially when visualizing deep veins or veins of a thick part of the body like the cubital fossa. This paper proposes a new vein-visualizing device applying a new penetration method using near-infrared (NIR) light. The light module is attached directly on to the declared area of the skin. Then, NIR beam is rayed from two sides of the light module to the vein with a specific angle. This gives a penetration effect. In addition, through an image processing procedure, the vein structure is enhanced to show it more accurately. Through a phantom study, the most effective penetration angle of the NIR module is decided. Additionally, the feasibility of the device is verified through experiments in vivo. The prototype allows us to visualize the vein patterns of thicker body parts, such as arms.

  13. Health impacts of garage workers: A preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Muttamara, S. (AIT, Bangkok (Thailand). Division of Environmental Engineering); Alwis, K.U.

    1994-05-01

    This research study was carried out in two automobile repair garages situated in the Bangkok metropolitan area, employing 47 and 12 workers respectively. Air sampling, biological monitoring (blood, urine), noise monitoring, and audiometry of workers were done to assess the occupational environment and its impact on the workers. The occupational hygiene survey was carried out to observe the working conditions of both garages. It was found that conditions at both sites have a strong negative impact on the health of workers. The lead in air of Garage 1 was 0.20 mg/m[sup 3] which is the same as the threshold limit value (TLV) for lead in air for a working environment. The level of lead in blood of four workers of each garage was above the exposed level. According to the occupational hygiene survey carried out at both garages, 79% of workers of Garage 1 and 70% of workers of Gage 2 suffered from redness of the eyes (eye pain, gritty feeling), and 5% and 2% of workers of Garage 1 and Garage 2 respectively, complained about breathing difficulties. Control measures should be taken to minimize pollution due to dust, fumes, and noise which would reduce the health impacts and lead to a healthier workforce.

  14. Preliminary studies on affirmative action in a brazilian university1

    Directory of Open Access Journals (Sweden)

    Eduardo de São Paulo

    2010-06-01

    Full Text Available As a signatory to Durban III World Conference against Racism, Discrimination, Xenophobia and other forms of Intolerance, Brazil has committed itself to the enforcement of mechanisms to promote social equity. As a consequence, governmental programs have been implemented, aiming at the inclusion of Afrodescendents h students in the academy is minimal and does not relate to what can be observed in the general population. As an example of such endeavor, Universidade de Brasília (UnB has started an Affirmative Action program in order to include a contingent of 20% of its freshman students as representatives of racial underprivileged groups. This policy started in August 2004. The present study aimed to investigate the perceptions of students and general public to this policy. An instrument, based partially on McConahay´s (1986 Modern Racism scale, was administered to a sample of 316 students. A factor analysis (AF extracted five factors, corresponding to 48% of the total variance explained. An Analysis of Variance (Anova was performed to better understand the results, concerning both age and gender of the subjects. Results show that, although students demonstrated interest in the implementing of Affirmative Action programs, and are aware of the relevance of such procedures to the cultural and social structure of the community, they do not agree with their reasons or measures taken, or to the existence of the problem itself.

  15. A preliminary study on drought events in Peninsular Malaysia

    Science.gov (United States)

    Zin, Wan Zawiah Wan; Nahrawi, Siti Aishah; Jemain, Abdul Aziz; Zahari, Marina

    2014-06-01

    In this research, the Standard Precipitation Index (SPI) is used to represent the dry condition in Peninsular Malaysia. To do this, data of monthly rainfall from 75 stations in Peninsular Malaysia is used to obtain the SPI values at scale one. From the SPI values, two drought characteristics that are commonly used to represent the dry condition in an area that is the duration and severity of a drought period are identified and their respective values calculated for every station. Spatial mappings are then used to identify areas which are more likely to be affected by longer and more severe drought condition from the results. As the two drought characteristics may be correlated with each other, the joint distribution of severity and duration of dry condition is considered. Bivariate copula model is used and five copula models were tested, namely, the Gumbel-Hougard, Clayton, Frank, Joe and Galambos copulas. The copula model, which best represents the relationship between severity and duration, is determined using Akaike information criterion. The results showed that the Joe and Clayton copulas are well-fitted by close to 60% of the stations under study. Based on the results on the most appropriate copula-based joint distribution for each station, some bivariate probabilistic properties of droughts can then be calculated, which will be continued in future research.

  16. The meanings of delusions in dementia: a preliminary study.

    Science.gov (United States)

    Cohen-Mansfield, Jiska; Golander, Hava; Ben-Israel, Joshua; Garfinkel, Doron

    2011-08-30

    One of the common symptoms of dementia is delusions. Due to a biological conceptualization of the behaviors represented as delusions, these are classified as psychotic symptoms. This is a qualitative and quantitative study aiming to describe the delusions experienced by older persons with dementia and the context of occurrence, and to elucidate their etiology. Participants were 74 nursing home residents aged 65 and over, diagnosed with dementia, from nine nursing homes in Israel. Participants with delusions were found to have significantly more difficulties in performing ADLs, and poorer vision and hearing. Based on assessment using the BEHAVE-AD, six categories of delusions were examined: 1. One's house is not one's home, 2. Theft, 3. Danger, 4. Abandonment, 5. Misidentification, and 6. Other non-paranoid. Common themes appeared across delusions including reality, disorientation, re-experience of past events, loneliness and insecurity, boredom, and trigger. Current results suggest that delusions may not represent psychotic symptoms for most participants, because they sometimes represented reality, or were neither firm nor incontrovertible. Thus, utilizing the term delusion relegates the person's behavior to the domain of severe psychiatric phenomena and precludes understanding its true meaning. Copyright © 2011. Published by Elsevier Ireland Ltd.

  17. An automatic tooth preparation technique: A preliminary study

    Science.gov (United States)

    Yuan, Fusong; Wang, Yong; Zhang, Yaopeng; Sun, Yuchun; Wang, Dangxiao; Lyu, Peijun

    2016-04-01

    The aim of this study is to validate the feasibility and accuracy of a new automatic tooth preparation technique in dental healthcare. An automatic tooth preparation robotic device with three-dimensional motion planning software was developed, which controlled an ultra-short pulse laser (USPL) beam (wavelength 1,064 nm, pulse width 15 ps, output power 30 W, and repeat frequency rate 100 kHz) to complete the tooth preparation process. A total of 15 freshly extracted human intact first molars were collected and fixed into a phantom head, and the target preparation shapes of these molars were designed using customised computer-aided design (CAD) software. The accuracy of tooth preparation was evaluated using the Geomagic Studio and Imageware software, and the preparing time of each tooth was recorded. Compared with the target preparation shape, the average shape error of the 15 prepared molars was 0.05–0.17 mm, the preparation depth error of the occlusal surface was approximately 0.097 mm, and the error of the convergence angle was approximately 1.0°. The average preparation time was 17 minutes. These results validated the accuracy and feasibility of the automatic tooth preparation technique.

  18. NEOWISE Studies of Asteroids with Sloan Photometry: Preliminary Results

    CERN Document Server

    Mainzer, A; Grav, T; Bauer, J; Tholen, D J; McMillan, R S; Wright, E; Spahr, T; Cutri, R M; Walker, R; Mo, W; Watkins, J; Hand, E; Maleszewski, C

    2011-01-01

    We have combined the NEOWISE and Sloan Digital Sky Survey data to study the albedos of 24,353 asteroids with candidate taxonomic classifications derived using Sloan photometry. We find a wide range of moderate to high albedos for candidate S-type asteroids that are analogous to the S-complex defined by previous spectrophotometrically-based taxonomic systems. The candidate C-type asteroids, while generally very dark, have a tail of higher albedos that overlaps the S types. The albedo distribution for asteroids with a photometrically derived Q classification is extremely similar to those of the S types. Asteroids with similar colors to (4) Vesta have higher albedos than the S types, and most have orbital elements similar to known Vesta family members. Finally, we show that the relative reflectance at 3.4 and 4.6 $\\mu$m is higher for D-type asteroids and suggest that their red visible and near-infrared spectral slope extends out to these wavelengths. Understanding the relationship between size, albedo, and taxon...

  19. Preliminary study of synergism of acid rain and diflubenzuron

    Energy Technology Data Exchange (ETDEWEB)

    Martin, P.J.S.; Clark, J.M.; Edman, J.D. [Univ. of Massachusetts, Amherst (United States)

    1995-06-01

    Diflubenzuron{sup 1} (Dimilin{reg_sign}) was used on over 7 million acres in the U.S. in 1990 to control forest pests, particularly the gypsy moth. This chitin synthesis inhibitor affects insects and other anthropods. It is a restricted use pesticide due to its nontarget effects on aquatic macroinvertebrates. The effects of a single aerial application on nontarget aquatic macroinvertebrate communities were reviewed by Eisler (1992). Crustacea and immature insects (especially the true flies, mosquitoes, midges and black flies) are the most sensitive nontarget aquatic organisms to diflubenzuron. Diflubenzuron, N-[[4-(chlorophenyl)amino]carbonyl]-2,6-difluorobenzamide, is not the only mortality factor aquatic organisms face from human pollution. Acid deposition is a frequent stress factor in freshwater habitats in the Northeast USA. Acidic pulses can drop vernal pools (e.g., temporary, springtime, snowmelt pools) to pH levels below 3.0. Aquatic invertebrates vary in their tolerance to acidification. Reduced pH completely eliminates some species. A combination of stress factors could lead to synergistic effects, over and above the impact seen with a single stressor. The purpose of this study was to determine if there are synergist effects of diflubenzuron and lowered pH on the mortality of a nontarget aquatic organism. 11 refs., 1 fig.

  20. A Preliminary Study of Active Region Canopies With AIA

    Science.gov (United States)

    Lucchini, Scott; Saar, S.; Muglach, K.

    2013-01-01

    Active region canopies are areas frequently accompanying active regions which have extensive horizontal magnetic fields. The large-scale canopy fields have a significant effect on the kinds of structures which can exist beneath them, and how they evolve. Using data from the Atmospheric Imaging Assembly (AIA), we developed methods to automatically identify these regions. A Differential Emission Measure (DEM) analysis is consistent with the idea that the long, hotter active region loops overlie quite cool, small-scale features ("fibrils"). We suggest that the overlying loops restrict the growth of underlying structures to mostly very short, cool features. We also studied evolution of canopy regions over time. In several cases, a large quiescent filament formed out of the former canopy region over the course of a few solar rotations, confirming previous suggestions. The canopy remains visible for several rotations after its active regions have begun to decay; in this time, the fibril magnetic fields gradually align in such a way as to form a filament channel. Further analysis of our large canopy database should uncover more information on the frequency and characteristics of these canopy-to-filament evolutions, as well as other canopy properties. This work is supported by the NSF REU program at SAO (grant ATM-0851866) and contract SP02H1701R from Lockheed Martin to SAO for SDO research.

  1. Social network analysis in identifying influential webloggers: A preliminary study

    Science.gov (United States)

    Hasmuni, Noraini; Sulaiman, Nor Intan Saniah; Zaibidi, Nerda Zura

    2014-12-01

    In recent years, second generation of internet-based services such as weblog has become an effective communication tool to publish information on the Web. Weblogs have unique characteristics that deserve users' attention. Some of webloggers have seen weblogs as appropriate medium to initiate and expand business. These webloggers or also known as direct profit-oriented webloggers (DPOWs) communicate and share knowledge with each other through social interaction. However, survivability is the main issue among DPOW. Frequent communication with influential webloggers is one of the way to keep survive as DPOW. This paper aims to understand the network structure and identify influential webloggers within the network. Proper understanding of the network structure can assist us in knowing how the information is exchanged among members and enhance survivability among DPOW. 30 DPOW were involved in this study. Degree centrality and betweenness centrality measurement in Social Network Analysis (SNA) were used to examine the strength relation and identify influential webloggers within the network. Thus, webloggers with the highest value of these measurements are considered as the most influential webloggers in the network.

  2. Preliminary Study for Designing a Novel Vein-Visualizing Device

    Science.gov (United States)

    Kim, Donghoon; Kim, Yujin; Yoon, Siyeop; Lee, Deukhee

    2017-01-01

    Venipuncture is an important health diagnosis process. Although venipuncture is one of the most commonly performed procedures in medical environments, locating the veins of infants, obese, anemic, or colored patients is still an arduous task even for skilled practitioners. To solve this problem, several devices using infrared light have recently become commercially available. However, such devices for venipuncture share a common drawback, especially when visualizing deep veins or veins of a thick part of the body like the cubital fossa. This paper proposes a new vein-visualizing device applying a new penetration method using near-infrared (NIR) light. The light module is attached directly on to the declared area of the skin. Then, NIR beam is rayed from two sides of the light module to the vein with a specific angle. This gives a penetration effect. In addition, through an image processing procedure, the vein structure is enhanced to show it more accurately. Through a phantom study, the most effective penetration angle of the NIR module is decided. Additionally, the feasibility of the device is verified through experiments in vivo. The prototype allows us to visualize the vein patterns of thicker body parts, such as arms. PMID:28178227

  3. Procurement challenges in the Zimbabwean public sector: A preliminary study

    Directory of Open Access Journals (Sweden)

    Abel Dzuke

    2015-02-01

    Full Text Available Background: State Procurement Board procedures and the public procurement process have been blamed for the lagging behind of government projects that impact on public service delivery in Zimbabwe.Objectives: This article provides insight into challenges resulting from the legal framework for public procurement in Zimbabwe that detract from service delivery.Method: Empirical data was collected through in-depth interviews with five participants at five public entities, using a semi-structured interview guide. Content analysis was used to analyse the primary data.Results: The findings revealed various challenges in the public procurement process that detract from service delivery. These include a lack of strategic recognition of the procurement function and procurement policy; a lack of professional, managerial and leadership skills; a lack of appropriated funds from Treasury; and a lack of accountability in the procurement process.Conclusion: There is a dearth of research on the public procurement process and its efficiency in Zimbabwe, and this study contributes to the existing body of knowledge by identifying areas through which public procurement can be improved in Zimbabwe.

  4. Correlated Networks of Magnetic and Inertial Sensors to Study Transient Phenomena

    Science.gov (United States)

    Zhivun, Elena; Gnome Collaboration; Nose Collaboration; Urban Magnetometer Network Collaboration

    2016-05-01

    We describe several new collaborative efforts to develop networks of magnetometers (the GNOME and Urban Magnetometer Network collaborations), atom interferometers (NOSE), and other precision sensors. These networks use geographically separated, time-synchronized sensors to search for correlated transient signals. The Global Network of Optical Magnetometers to search for Exotic physics (GNOME) searches for nuclear and electron spin couplings to various exotic fields generated by astrophysical sources. The UC Network Of Sensors for Exotic physics (NOSE) searches for dark matter and dark energy by detecting the influence of a background field of ultra-light particles with a network of various sensors such as atom interferometers, novel solid-state acceleration sensors, and GNOME magnetometers. The Urban Magnetometer Network project characterizes and determines the origin of the ambient field fluctuations, in order to to improve magnetic anomalies detection and extract maximal information from magnetic signals in the city environment. Global Network of Optical Magnetometers.

  5. Comprehensive transient-state study for CARMENES-NIR high thermal stability

    CERN Document Server

    Becerril, S; Cárdenas, M C; Rabaza, O; Ramón, A; Abril, M; Costillo, L P; Morales, R; Rodríguez, A; Amado, P J

    2010-01-01

    CARMENES has been proposed as a next-generation instrument for the 3.5m Calar Alto Telescope. Its objective is finding habitable exoplanets around M dwarfs through radial velocity measurements (m/s level) in the near-infrared. Consequently, the NIR spectrograph is highly constraint regarding thermal/mechanical requirements. As a first approach, the thermal stability has been limited to \\pm 0.01K (within year period) over a working temperature of 243K. This can be achieved by means of several temperature-controlled rooms. The options considered to minimise the complexity of the thermal design are here presented, as well as the transient-state thermal analyses realised to make the best choice.

  6. Single Event Transient and TID Study in 28 nm UTBB FDSOI Technology

    Science.gov (United States)

    Liu, Rui; Evans, Adrian; Chen, Li; Li, Yuanqing; Glorieux, Maximilien; Wong, Richard; Wen, Shi-Jie; Cunha, Joao; Summerer, Leopold; Ferlet-Cavrois, Véronique

    2017-01-01

    Measuring single-event transient (SET) pulse widths is critical for developing proper mitigation schemes to single-event effects (SEE), especially for advanced technologies. This paper presents a test chip design implementing advanced techniques for measuring SETs implemented in a 28 nm Ultra-Thin Body and Box (UTBB) FDSOI technology. Experimental results of heavy ion and Co-60 irradiation experiments are presented. The heavy ion experiments confirm that this technology has very low SEE sensitivity. Laser test results show that pulse distortion (broadening) plays a key role when evaluating the effect of SETs. Total Ionizing Dose (TID) effects were also evaluated by measuring the Ring Oscillator (RO) frequencies and static current during heavy ion and Co-60 irradiation. Experimental results showed that the RO frequencies degraded up to 10% (heavy ion), and 40% (Co-60) after 1000 krad(Si) irradiation, but the logic in the chip functioned without error.

  7. A numerical study of transient heat and mass transfer in crystal growth

    Science.gov (United States)

    Han, Samuel Bang-Moo

    1987-01-01

    A numerical analysis of transient heat and solute transport across a rectangular cavity is performed. Five nonlinear partial differential equations which govern the conservation of mass, momentum, energy and solute concentration related to crystal growth in solution, are simultaneously integrated by a numerical method based on the SIMPLE algorithm. Numerical results showed that the flow, temperature and solute fields are dependent on thermal and solutal Grashoff number, Prandtl number, Schmidt number and aspect ratio. The average Nusselt and Sherwood numbers evaluated at the center of the cavity decrease markedly when the solutal buoyancy force acts in the opposite direction to the thermal buoyancy force. When the solutal and thermal buoyancy forces act in the same direction, however, Sherwood number increases significantly and yet Nusselt number decreases. Overall effects of convection on the crystal growth are seen to be an enhancement of growth rate as expected but with highly nonuniform spatial growth variations.

  8. Modeling and Experimental Study of PEM Fuel Cell Transient Response for Automotive Applications

    Institute of Scientific and Technical Information of China (English)

    HUA Jianfeng; XU Liangfei; LIN Xinfan; LU Languang; OUYANG Minggao

    2009-01-01

    This paper presents an analysis of the dynamic response of a low pressure proton exchange membrane (PEM) fuel cell stack to step changes in load, which are characteristic of automotive fuel cell system applications. The goal is a better understanding of the electrical and electrochemical processes when accounting for the characteristic cell voltage response during transients. The analysis and experiment are based on a low pressure 5 kW proton exchange membrane fuel cell (PEMFC) stack, which is similar to those used in several of Tsinghua's fuel cell buses. The experimental results provide an effective improvement reference for the power train control scheme of the fuel cell buses in Olympic demonstration in Beijing 2008.

  9. STUDY ON CATASTROPHIC MECHANISM FOR ROTOR DROP TRANSIENT VIBRATION FOLLOWING MAGNETIC BEARING FAILURE

    Institute of Scientific and Technical Information of China (English)

    方之楚

    2002-01-01

    The nonlinear and transient vibration of a rotor, which dropped onto back-up bearings when its active magnetic bearings were out of order, was investigated. After strictly deriving its equations of motion and performing numerical simulations, the timehistories of rotating speed of the dropping rotor, and normal force at the rubbing contact point as well as the frequency spectrum of the vibration displacement of back-up bearings are fully analyzed. It is found that the strong and unsteady forced bending vibration of the unbalanced and damped rotor decelerating through its first bending vibtation of the unbalanced and damped rotor decelerating through its first critical speed as well as chattering at high frequencies caused by the nonlinearity at the rubbing contact point between the journal and back-up bearings may lead to the catastrophic damage of the system.

  10. Neuronal precursor cell proliferation in the hippocampus after transient cerebral ischemia: a comparative study of two rat strains using stereological tools

    DEFF Research Database (Denmark)

    Kelsen, Jesper; Larsen, Marianne; Sørensen, Jens Christian H.;

    2010-01-01

    We are currently investigating microglial activation and neuronal precursor cell (NPC) proliferation after transient middle cerebral artery occlusion (tMCAo) in rats. This study aimed: (1) to investigate differences in hippocampal NPC proliferation in outbred male spontaneously hypertensive rats ...

  11. Risk of caries and oral health: preliminary study

    Directory of Open Access Journals (Sweden)

    Marcello Gatti

    2009-12-01

    Full Text Available Introduction. The incidence of injury cariosa remains high, despite the improvements achieved in the last years. Recent national epidemiological surveys, 4 years old children have healthy teeth in 80% of cases at 12 years the percentage is reduced to 50%. In Italy, the almost total absence on the territory of “dental services to the Community”, makes even more difficult to achieve a solution to the problem “caries.” To address this problem, the Ministry of Labor, Health and Social Policy in October 2008 adopted the national guidelines in order to make suggestions to the various professionals (pediatricians, dentists, microbiologists, dental hygienists, etc., making them interact to maintain and restore oral health. It was the first time that the Ministry of Health has addressed the problem by inserting the figure of the microbiologist in dentistry. Aims. The present study aim was to identify subjects at risk of caries by clinical microbiological testing of saliva and the index DMFT/dmft (Decayed, Missing and Filling Permanent Teeth in both adults and particularly children in order to take preventive measures early as reported in “National guidelines for the promotion of oral health and prevention of oral diseases in age of development”. The study began in June 2009 and will last one year with as goal to have, in 2010, 90% of children between 5 and 6 years caries free and 18 years with any lost tooth decay. Materials and methods. Recruited 164 patients were divided into three age groups: 124 adults aged between 20 and 40 years, 40 children which 21 till 5 years old and 19 till 12 years old. Microbiological testing was aimed by finding CFU / ml of saliva of Streptococcus mutans and Lactobacillus spp., Slide CRT bacteria (Ivoclar. Clinically, intraoral examination was performed to evaluate the DMFT (Decayed teeth, Missing or Filling calculated over 28 permanent teeth and the dmft (decayed teeth, missing or filling calculated on 20

  12. Smart garment for trunk posture monitoring: A preliminary study

    Directory of Open Access Journals (Sweden)

    Wong Man

    2008-05-01

    Full Text Available Abstract Background Poor postures of the spine have been considered in association with a number of spinal musculoskeletal disorders, including structural deformity of the spine and back pain. Improper posturing for the patients with spinal disorders may further deteriorate their pain and deformities. Therefore, posture training has been proposed and its rationale is to use the patient's own back muscles to keep the spine within the natural curvature. A posture training device may help to facilitate this therapeutic approach by providing continuous posture monitoring and feedback signals to the patient when "poor" posture is detected. In addition, the users of the device may learn good postural habits that could carry over into their whole life. Methods A smart garment with integrated accelerometers and gyroscopes, which can detect postural changes in terms of curvature variation of the spine in the sagittal and coronal planes, has been developed with intention to facilitate posture training. The smart garment was evaluated in laboratory tests and with 5 normal subjects during their daily activities. Results Laboratory tests verified that the accuracy of the system is Conclusion The smart garment has been developed to be a portable and user-friendly trunk posture monitoring system and it could be used for collection of the trunk posture information and provision of instant feedback to the user if necessary for posture training purpose. The current pilot study demonstrated that the posture of normal subjects could be monitored and trained via this smart garment. With further clinical investigations, this system could be considered in some flexible spinal deformities such as scoliosis and kyphosis.

  13. Preliminary fsLIBS study on bone tumors.

    Science.gov (United States)

    Gill, Ruby K; Smith, Zachary J; Panchal, Ripul R; Bishop, John W; Gandour-Edwards, Regina; Wachsmann-Hogiu, Sebastian

    2015-12-01

    The aim of this study is to evaluate the capability of femtosecond Laser Induced Breakdown Spectroscopy (fsLIBS) to discriminate between normal and cancerous bone, with implications to femtosecond laser surgery procedures. The main advantage of using femtosecond lasers for surgery is that the same laser that is being used to ablate can also be used for a feedback system to prevent ablation of certain tissues. For bone tumor removal, this technique has the potential to reduce the number of repeat surgeries that currently must be performed due to incomplete removal of the tumor mass. In this paper, we performed fsLIBS on primary bone tumor, secondary tumor in bone, and normal bone. These tissues were excised from consenting patients and processed through the UC Davis Cancer Center Biorepository. For comparison, each tumor sample had a matched normal bone sample. fsLIBS was performed to characterize the spectral signatures of each tissue type. A minimum of 20 spectra were acquired for each sample. We did not detect significant differences between the fsLIBS spectra of secondary bone tumors and their matched normal bone samples, likely due to the heterogeneous nature of secondary bone tumors, with normal and cancerous tissue intermingling. However, we did observe an increase in the fsLIBS magnesium peak intensity relative to the calcium peak intensity for the primary bone tumor samples compared to the normal bone samples. These results show the potential of using femtosecond lasers for both ablation and a real-time feedback control system for treatment of primary bone tumors.

  14. Cerebrocerebellar system and Arnold's bundle: A tractographic study: preliminary results

    Directory of Open Access Journals (Sweden)

    Eliasz Engelhardt

    Full Text Available Abstract The cerebellum, traditionally considered a structure involved in balance and movement control, was more recently recognized as important in cognitive, emotional and behavioral functions. These functions appear to be related to the more recent parts of the cerebellum that belong to the cerebrocerebellar system. One of the key segments of this system is the (prefronto-[penduncule]-pontine projection that represents the Arnold's bundle. Diffusion tensor imaging and tractography (DTI-TR has permitted in vivo virtual dissection of white matter tracts, including those of the cerebellar. Objective: To study the fronto-[peduncule]-pontine projection (Arnold's bundle, with DTI-TR. Methods: Ten normal subjects were included (mean age 30 years. Standard acquisitions in three planes were obtained with a 1.5T GE Signa Horizon scanner, complemented with DTI acquisitions. Post-processing and analysis was performed using an ADW 4.3 workstation running Functool 4.5.3 (GE Medical Systems. A single ROI was placed on the medial third of the cerebral peduncle base, considered the site of convergence of the fibers of Arnold's bundle, bilaterally. Results: Twenty tractograms were obtained. All were constituted by a significant number of fibers in correspondence to the frontal lobe, and part of them anterior to the coronal plane at the anterior commissure, which characterizes them as associated to the prefrontal region. Conclusions: For the first time, frontal lobe related projections were systematically revealed with DTI-TR seeded from cerebral peduncle base ROIs. They showed anatomic coherence with Arnold's bundle, which includes the prefrontopontine segment of the cortico-ponto-cerebellar path, one of the components of the cerebrocerebellar system, acknowledged as fundamental for non-motor functions such as cognition, emotion and behavior.

  15. A Preliminary Study on Dust Grains in the Stratosphere

    Institute of Scientific and Technical Information of China (English)

    黄伯钧; 欧阳自远; 等

    1990-01-01

    Collected by means of a high-altitude scientific balloon and a self-made automatic sample collector,a total of 276 dust grains were selected for the study of shape,grain size and optical property.Some of the grains were examined by X-ray diffraction and electrom microprobe techniques,The stratospheric dust grains can be classified as 6 types:cosmic dusts,cosmic dusts(?),microtektite,natural pollutants,artificial pollutants and the unknown substances.The different types of dust grains have different characters and distinguishing symbols.Widespread in the space of the solar system,cosmic dusts are the initial substances of the solar system and ,to some degree,have recorded a great wealth of information on the early history of the solar system.So they have become one of the important objects in the field of cosmochemistry at present time,Since the 1960's,scholars of many countries have collected cosmic dusts both in the space near the earth(using rock ets,space probes and space shuttles)and in the stratosphere (using high-altitude balloons or U-2air planes).According to the shape(the scanning electron microimage),element composition(the energy-dispersive X-ray spectrum)and optical properties of dust grains,the substances in the stratosphere can be classified as 5 types:cosmic dusts,alumina spheroids,terrestrial artificial pollutants,terrestrial natural pollutants and unknown substances(CDPET,1982).

  16. Preliminary design study of the Tandem Mirror Reactor (TMR)

    Energy Technology Data Exchange (ETDEWEB)

    Moir, R.W.; Barr, W.L.; Carlson, G.A.

    1978-07-15

    This report describes work done in Fiscal Year 1977 by the Fusion Reactor Studies Group of LLL on the conceptual design of a 1000-MW(e) Tandem Mirror Reactor (TMR). The high Q (defined as the ratio of fusion power to injection power) predicted for the TMR (approximately 5) reduces the recirculating power to a nondominant problem and results in an attractive mirror fusion power plant. The fusion plasma of the TMR is contained in the 100-m-long central cell where the magnetic field strength is a modest 2 T. The blanket for neutron energy recovery and tritium breeding is cylindrical and, along with the solenoidal magnet, is divided into 3-m-long modules to facilitate maintenance. The central cell is fueled (but not heated) by the injection of low-energy neutral beams near its ends. Thus, the central cell is simple and of low technology. The end-cell plasmas must be of high density and high energy in order to plug and heat (via the electrons) the central-cell plasma. The present conceptual design uses 1.2-MeV neutral-beam injection for the end plugs and a cryogenic-aluminum, Yin-Yang magnet that produces an incremental field of about 1 T over a field of 16 T produced by a pair of Nb/sub 3/Sn superconducting solenoids. Important design problems remain in both the neutral-beam injector and in the end-plug magnet. Also remaining are important physics questions such as alpha-beam particle transport and end-plug stability. These questions are discussed at length in the report and suggestions for future work are given.

  17. COMMUNITIES OF PRACTICE IN UNIVERSITY: A PRELIMINARY STUDY

    Directory of Open Access Journals (Sweden)

    MARGARISOVÁ, Klára

    2011-09-01

    Full Text Available There has been a lot written about the benefits of communities of practice (CoP in university. The benefit of the communities of practice was described with respect to teachers’ qualification and teaching competencies influencing students implicitly as well as to areas related to the students themselves. Many studies prove the fact that the process of learning is of a social character (e.g. Lave, Wenger, 1991. That is why the communities of practice present suitable environment for collaborative learning which makes the process of generating, sharing and storing knowledge easier. The present paper defines on a theoretical level the concept of the communities of practice and moreover, provides a brief overview of the latest research in the communities of practice with regard to education. Another part of the article focuses on the pre-research of the communities of practice at Faculty of Economics and Management (FEM Czech University of Life Sciences Prague (CULS. Although the authors conform with the opinion that the communities of practice are a natural feature and spontaneously develop wherever there is a need for sharing implicit or tacit knowledge, the pre-research focused on the verification of this premise in order to continue in the research of a quantitative character. The existence of the communities of practice was verified on the basis of fundamental characteristics following Wenger’s model. Other characteristics, considered significant in relation to the communities of practice by McDermott were also investigated. Based on a group interview the existence of the communities of practice of the students at FEM at CULS has been verified and a conceptual model was created. The determined work prerequisites will be investigated in another phase of the research.

  18. Paraconsistent artificial neural networks and Alzheimer disease: A preliminary study

    Directory of Open Access Journals (Sweden)

    Jair Minoro Abe

    Full Text Available Abstract EEG visual analysis has proved useful in aiding AD diagnosis, being indicated in some clinical protocols. However, such analysis is subject to the inherent imprecision of equipment, patient movements, electric registers, and individual variability of physician visual analysis. Objectives: To employ the Paraconsistent Artificial Neural Network to ascertain how to determine the degree of certainty of probable dementia diagnosis. Methods: Ten EEG records from patients with probable Alzheimer disease and ten controls were obtained during the awake state at rest. An EEG background between 8 Hz and 12 Hz was considered the normal pattern for patients, allowing a variance of 0.5 Hz. Results: The PANN was capable of accurately recognizing waves belonging to Alpha band with favorable evidence of 0.30 and contrary evidence of 0.19, while for waves not belonging to the Alpha pattern, an average favorable evidence of 0.19 and contrary evidence of 0.32 was obtained, indicating that PANN was efficient in recognizing Alpha waves in 80% of the cases evaluated in this study. Artificial Neural Networks - ANN - are well suited to tackle problems such as prediction and pattern recognition. The aim of this work was to recognize predetermined EEG patterns by using a new class of ANN, namely the Paraconsistent Artificial Neural Network - PANN, which is capable of handling uncertain, inconsistent and paracomplete information. An architecture is presented to serve as an auxiliary method in diagnosing Alzheimer disease. Conclusions: We believe the results show PANN to be a promising tool to handle EEG analysis, bearing in mind two considerations: the growing interest of experts in visual analysis of EEG, and the ability of PANN to deal directly with imprecise, inconsistent, and paracomplete data, thereby providing a valuable quantitative analysis.

  19. Electrostatic interactions in the binding pathway of a transient protein complex studied by NMR and isothermal titration calorimetry.

    Science.gov (United States)

    Meneses, Erick; Mittermaier, Anthony

    2014-10-03

    Much of our knowledge of protein binding pathways is derived from extremely stable complexes that interact very tightly, with lifetimes of hours to days. Much less is known about weaker interactions and transient complexes because these are challenging to characterize experimentally. Nevertheless, these types of interactions are ubiquitous in living systems. The combination of NMR relaxation dispersion Carr-Purcell-Meiboom-Gill (CPMG) experiments and isothermal titration calorimetry allows the quantification of rapid binding kinetics for complexes with submillisecond lifetimes that are difficult to study using conventional techniques. We have used this approach to investigate the binding pathway of the Src homology 3 (SH3) domain from the Fyn tyrosine kinase, which forms complexes with peptide targets whose lifetimes are on the order of about a millisecond. Long range electrostatic interactions have been shown to play a critical role in the binding pathways of tightly binding complexes. The role of electrostatics in the binding pathways of transient complexes is less well understood. Similarly to previously studied tight complexes, we find that SH3 domain association rates are enhanced by long range electrostatics, whereas short range interactions are formed late in the docking process. However, the extent of electrostatic association rate enhancement is several orders of magnitudes less, whereas the electrostatic-free basal association rate is significantly greater. Thus, the SH3 domain is far less reliant on electrostatic enhancement to achieve rapid association kinetics than are previously studied systems. This suggests that there may be overall differences in the role played by electrostatics in the binding pathways of extremely stable versus transient complexes.

  20. Electrostatic Interactions in the Binding Pathway of a Transient Protein Complex Studied by NMR and Isothermal Titration Calorimetry*

    Science.gov (United States)

    Meneses, Erick; Mittermaier, Anthony

    2014-01-01

    Much of our knowledge of protein binding pathways is derived from extremely stable complexes that interact very tightly, with lifetimes of hours to days. Much less is known about weaker interactions and transient complexes because these are challenging to characterize experimentally. Nevertheless, these types of interactions are ubiquitous in living systems. The combination of NMR relaxation dispersion Carr–Purcell–Meiboom–Gill (CPMG) experiments and isothermal titration calorimetry allows the quantification of rapid binding kinetics for complexes with submillisecond lifetimes that are difficult to study using conventional techniques. We have used this approach to investigate the binding pathway of the Src homology 3 (SH3) domain from the Fyn tyrosine kinase, which forms complexes with peptide targets whose lifetimes are on the order of about a millisecond. Long range electrostatic interactions have been shown to play a critical role in the binding pathways of tightly binding complexes. The role of electrostatics in the binding pathways of transient complexes is less well understood. Similarly to previously studied tight complexes, we find that SH3 domain association rates are enhanced by long range electrostatics, whereas short range interactions are formed late in the docking process. However, the extent of electrostatic association rate enhancement is several orders of magnitudes less, whereas the electrostatic-free basal association rate is significantly greater. Thus, the SH3 domain is far less reliant on electrostatic enhancement to achieve rapid association kinetics than are previously studied systems. This suggests that there may be overall differences in the role played by electrostatics in the binding pathways of extremely stable versus transient complexes. PMID:25122758

  1. Shock absorption in lumbar disc prosthesis: a preliminary mechanical study.

    Science.gov (United States)

    LeHuec, J C; Kiaer, T; Friesem, T; Mathews, H; Liu, M; Eisermann, L

    2003-08-01

    Lumbar disc prostheses have been used in treating symptomatic degenerative disc diseases. A few prostheses of the ball-socket design are currently available for clinical use, the joint mechanism being materialized either with a hard polymer core or a metal-to-metal couple. Other prostheses of "shock absorber" design were not available at the time of the study. The objective of this work was to establish whether there was a difference in the shock absorption capacity between a device having an ultra-high-molecular-weight polyethylene center core and a device having a metal-on-metal bearing. Vibration and shock loading were applied to two lumbar total disc prostheses: PRODISC, manufactured by Spine Solutions, and MAVERICK Total Disc Replacement, manufactured by Medtronic Sofamor Danek. The shock absorption capacity of the device was evaluated by comparing the input and the output force measurements. The disc prosthesis was mounted onto a test apparatus. Each side of the device was equipped with a force sensor. The input shock load and the output resulting forces were simultaneously measured and recorded. The loading force pattern included 1). a static preload of 350 N plus an oscillating vibration of 100 N with frequency sweeping from 0 to 100 Hz and 2). a sudden shock load of 250 N applied over a 0.1-second interval. Both input and output signal data were processed and were transformed into their frequency spectrums. The vibration and shock transmissibility of the device, defined as the ratio of the output spectrum over the input spectrum, were calculated in sweeping the frequency from 0 to 100 Hz. The phase deviation was calculated to characterize the shock absorber effects. For both tested devices under vibration and shock loading, the phase angle displacement between the input and the output signals was 10 degrees. Under oscillating vibration loading, both tested devices had a transmission ratio higher than 99.8%. Over the frequency interval 1-100 Hz, the

  2. Preliminary study of diffusion effects in Fricke gel dosimeters

    Energy Technology Data Exchange (ETDEWEB)

    Quiroga, A. [Centro de Investigacion y Estudios de Matematica de Cordoba, Oficina 318 FaMAF - UNC, Ciudad Universitaria, 5000 Cordoba (Argentina); Vedelago, J. [Laboratorio de Investigaciones e Instrumentacion en Fisica Aplicada a la Medicina e Imagenes por Rayos X, Laboratorio 448 FaMAF - UNC, Ciudad Universitaria, 5000 Cordoba (Argentina); Valente, M., E-mail: aiquiroga@famaf.unc.edu [Instituto de Fisica Enrique Gaviola, Oficina 102 FaMAF - UNC, Av. Luis Medina Allende, Ciudad Universitaria, 5000 Cordoba (Argentina)

    2014-08-15

    Diffusion of ferric ions in ferrous sulfate (Fricke) gels represents one of the main drawbacks of some radiation detectors, like Fricke gel dosimeters. In practice, this disadvantage can be overcome by prompt dosimeter analysis, constraining strongly the time between irradiation and analysis. Due to required integral accuracy levels, special dedicated protocols are implemented with the aim of minimizing signal blurring due to diffusion effects. This work presents dedicated analytic modelling and numerical calculations of diffusion coefficients in Fricke gel radiation sensitive material. Samples are optically analysed by means of visible light transmission measurements capturing images with a Ccd camera provided with a monochromatic 585 nm filter corresponding to the X O-infused Fricke solution absorbance peak. Dose distributions in Fricke gels are suitably delivered in order to assess specific initial conditions further studied by periodical sample image acquisitions. In a first analytic approach, experimental data are fit with linear models in order to achieve a value for the diffusion coefficient. The second approach to the problem consists on a group of computational algorithms based on inverse problem formulation, along with suitable 2D diffusion model capable of estimating diffusion coefficients by fitting the obtained algorithm numerical solutions with the corresponding experimental data. Comparisons are performed by introducing an appropriate functional in order to analyse both experimental and numerical values. Solutions to second order diffusion equation are calculated in the framework of a dedicated method that incorporates Finite Element Method. Moreover, optimised solutions can be attained by gradient type minimisation algorithms. Knowledge about diffusion coefficient for Fricke gel radiation detector might be helpful in accounting for effects regarding elapsed time between dosimeter irradiation and further analysis. Hence, corrections might be included

  3. Occlusal traits in developmental dyslexia: a preliminary study

    Directory of Open Access Journals (Sweden)

    Perillo L

    2013-08-01

    Full Text Available Letizia Perillo,1 Maria Esposito,2 Mariarosaria Contiello,1 Alessandra Lucchese,3 Annamaria Chiara Santini,2 Marco Carotenuto2 1Department of Orthodontics, Second University of Naples, Naples, 2Clinic of Child and Adolescent Neuropsychiatry, Department of Mental Health, Physical and Preventive Medicine, Second University of Naples, Naples, 3Department of Orthodontics, University of Ferrara, Ferrara, Italy Aim: The objective of the study reported here was to assess the orthodontic features in children affected by developmental dyslexia (DD. Patients and methods: A total of 28 children affected by DD (22 boys, six girls; mean age: 9.78 ± 1.69 years were compared with 51 healthy children (38 boys, 13 girls; mean age 9.41 ± 1.48; range 7–10 years. Reading and writing skills were evaluated along with orthodontic features. Results: The DD and control groups were not significantly different in terms of total intelligence quotient (P = 0.441 and writing skills (P = 0.805 and P = 0.240, respectively, whereas significant differences were observed between the DD group and control group in both word reading (2.018 ± 1.714 vs 0.917 ± 0.563; P = 0.000 and non-word reading (2.537 ± 1.543 vs 0.862 ± 0.244; P = 0.000. Moreover, for many orthodontic features, there was no significant difference between the two groups; only in prevalence of diastemas (57.14%, P = 0.006, midline diastemas (46.42%, P = 0.007, overbite >4 mm (71.42%, P = 0.006 and overjet >4 mm (53.57%, P = 0.001, was there a statistically significant difference. According to univariate logistic regression analysis, the presence of diastemas (odds ratio [OR] 4.33; 95% confidence interval [CI] 1.61–11.65, midline diastemas (OR 4.68; 95% CI 1.61–13.43, an overbite >4 mm (OR 1.75; 95% CI 0.64–4.71, or an overjet >4 mm (OR 2.76; 95% CI 1.06–7.20 seems to play a role in the relationship between occlusal abnormalities and DD in children. Conclusion: Children with DD tend to present with

  4. Deep level transient spectroscopy studies of n-type ZnO single crystals grown by different techniques.

    Science.gov (United States)

    Scheffler, L; Kolkovsky, Vl; Lavrov, E V; Weber, J

    2011-08-24

    In the present study single-crystalline ZnO samples grown from the vapor phase, the melt, and a high-temperature aqueous solution (hydrothermal growth) are investigated before and after hydrogen plasma treatments, by means of deep level transient spectroscopy (DLTS) and high-resolution Laplace DLTS. Dominant DLTS peaks are found to appear in the range of 120-350 K for all materials. The DLTS spectra depend on the procedure of growth of the ZnO. The thermal stabilities of the defects in an oxygen atmosphere and in an oxygen-lean atmosphere are analyzed. The origin of the DLTS peaks is discussed.

  5. Deep level transient spectroscopy studies of n-type ZnO single crystals grown by different techniques

    Energy Technology Data Exchange (ETDEWEB)

    Scheffler, L; Kolkovsky, Vl; Lavrov, E V; Weber, J [Technische Universitaet Dresden, 01062 Dresden (Germany)

    2011-08-24

    In the present study single-crystalline ZnO samples grown from the vapor phase, the melt, and a high-temperature aqueous solution (hydrothermal growth) are investigated before and after hydrogen plasma treatments, by means of deep level transient spectroscopy (DLTS) and high-resolution Laplace DLTS. Dominant DLTS peaks are found to appear in the range of 120-350 K for all materials. The DLTS spectra depend on the procedure of growth of the ZnO. The thermal stabilities of the defects in an oxygen atmosphere and in an oxygen-lean atmosphere are analyzed. The origin of the DLTS peaks is discussed.

  6. A preliminary study of visual memory and rule detection in fencing. A comparative study

    Directory of Open Access Journals (Sweden)

    EVANGELOS VERTOPOULOS, CHARILAOS TSOLAKIS & MARIETTA REMOUNDOU

    2010-01-01

    Full Text Available The purpose of this preliminary study was to investigate possible differences among a group of fencers and a group of swimmers, in the visual memory task and the spatial anticipation task. 15 national level fencers (aged between 16 to 23 years and 15 swimmers of a competitive swimming club (aged between 15 to 22 years, were studied. The Brixton Spatial Anticipation Test (BSAT was used as a measure of executive functioning. The second test was the Visual Patterns Test (VPT, which measured visual short-term memory. The Digit Span subtest of the Wechsler Adult Intelligence Scale-III (WAIS was also included as an estimate of general intelligence. There was a significant difference between fencers & swimmers in the BSAT, (F=5.261, p<0.030, while the analysis of the VPT test scores showed no significant differences among groups (F=0.325 p<=0.573. In conclusion, fencers showed no better performance on visual memory, while they were superior in rule detection, comparing to swimmers. The long training fencing program, may greatly affects the speed of constitute information process as attributes of the decision making speed in national level fencers.

  7. Preliminary study of quinine pharmacokinetics in pregnant women with malaria-HIV co-infection.

    Science.gov (United States)

    Kayentao, Kassoum; Guirou, Etienne A; Doumbo, Ogobara K; Venkatesan, Meera; Plowe, Christopher V; Parsons, Teresa L; Hendrix, Craig W; Nyunt, Myaing M

    2014-03-01

    Pregnant women bear the greatest burden of malaria-human immunodeficiency virus co-infection. Previous studies suggest that interaction with antiretroviral drugs may compromise antimalarial pharmacokinetics and treatment outcomes. We conducted a preliminary clinical study to assess quinine pharmacokinetics in Malian pregnant women with acute malaria who reported taking nevirapine-based antiretroviral therapy. Of seven women, six had stable concentrations of nevirapine in the plasma and one had none. Quinine concentrations were lower, and its metabolite 3-hydroxyquinine higher, in the six women with nevirapine than in the one without, and quinine concentrations were below the recommended therapeutic range in 50% of the women. This preliminary observation warrants further research to understand the impact of long-term antiretroviral therapy on the treatment of acute malaria.

  8. Identification and preliminary SAR studies of (+)-Geodin as a glucose uptake stimulator for rat adipocytes.

    Science.gov (United States)

    Sato, Seiichi; Okusa, Noriyuki; Ogawa, Akiyo; Ikenoue, Takao; Seki, Tetsuya; Tsuji, Takashi

    2005-09-01

    (+)-Geodin (1) was isolated from Penicillium glabrum AJ117540 with activity that stimulates glucose uptake by rat adipocytes. Unlike insulin it is active in the presence of wortmannin. Dihydrogeodin (2) and sulochrin (3) which are the precursors of (+)-geodin biosynthesis were also isolated from the same fungus. Preliminary SAR studies of 1 showed some analogues had enhanced activity. Especially, the activities of racemic geodin and dibromo analogue (7a) were comparable to that of the natural product. Geodin (1), a known fungal metabolite, was isolated from Penicillium glabrum AJ117540 as an active substance (Fig. 1). Dihydrogeodin (2) and sulochrin (3), the precursors of 1, were also isolated from the same fungal extract. In this study, preliminary mechanistic insight and SAR are reported.

  9. PRELIMINARY PHYTOCHEMICAL ANALYSIS AND ACUTE ORAL TOXICITY STUDY OF CLITORIA TERNATEA LINN. ROOTS IN ALBINO MICE

    Directory of Open Access Journals (Sweden)

    Deka Manalisha

    2011-12-01

    Full Text Available Clitoria ternatea has been using since the ancient times for its medicinal values. Almost all the parts of the plant have medicinal property. The root of the plant is reported to have anti diarrheal, Anti histamic, cholinergic activity etc. Traditionally the root has been using for the treatment of many diseases like leucorrhoea, diarrhea, urinary problems, diuretic, impotency, stomach trouble etc. The present study was designed to investigate the preliminary phytochemical analysis and acute oral toxicity of the root of the plant. The shed dried materials were grinded and used in the study. The preliminary phytochemical analysis was done by following standard protocols. For acute oral toxicity study, methanolic extract of the root was used. The extract was prepared by standard protocol. The preliminary phytochemical analysis showed the presence of proteins, carbohydrates, glycosides, resins, saponin, flavonoid, alkaloids, steroids and phenol. The acute oral toxicity study showed no mortality up to a dose of 3000 mg per kg body weight. The presence of plant chemicals revealed the medicinal values and the non toxic property of the plant indicated the value of the plant as medicine. Thus we can conclude that, the root of the plant can be used as a safe drug against many diseases.

  10. Synopsis of some preliminary computational studies related to unsaturated zone transport at Area G

    Energy Technology Data Exchange (ETDEWEB)

    Vold, E.

    1998-03-01

    Computational transport models are described with applications in three problem areas related to unsaturated zone moisture movement beneath Area G. These studies may be used to support the ongoing maintenance of the site Performance Assessment. The three areas include: a 1-D transient analysis with average tuff hydraulic properties in the near surface region with computed results compared to field data; the influence on near surface transient moisture percolation due to realistic distributions in hydraulic properties derived statistically from the observed variance in the field data; and the west to east moisture flow in a 2-D steady geometry approximation of the Pajarito Plateau. Results indicate that a simple transient model for transport of moisture volume fraction fits field data well compared to a moisture pulse observed in the active disposal unit, pit 37. Using realistic infiltration boundary conditions for summer showers and for spring snow melt conditions, the computed moisture pulses show significant propagation to less than 10-ft depth. Next, the hydraulic properties were varied on a 2-D grid using statistical distributions based on the field data means and variances for the hydraulic parameters. Near surface transient percolation in these conditions shows a qualitatively realistic percolation with a spatially variable wave front moving into the tuff; however, the flow does not channel into preferred paths and suggests there is no formation of fast paths which could enhance transportation of contaminants. Finally, moisture transport is modeled through an unsaturated 2-D slice representing the upper stratigraphic layers beneath Area G and a west-to-east cut of several miles to examine possible lateral movement from the west where percolation is assumed to be greater than at Area G. Results show some west-to-east moisture flux consistent with the assumed profile for the percolation boundary conditions.

  11. Towards a quantitative study of the VUV photolysis of methane: preliminary experiment on trichloromethane

    Science.gov (United States)

    Gans, B.; Boyé-Péronne, S.; Douin, S.; Gauyacq, D.

    2010-01-01

    Photolysis of methane in Titan's stratosphere is the starting point of gas phase carbon chemistry. Quantitative studies of methane photolytic products are of utmost importance for Titan atmosphere models. With this aim, two experimental strategies are presented in this article. Preliminary results demonstrate the possibility of using CRDS absorption coupled with pulsed photolysis on the example of a halogenated derivative of methane: Trichloromethane (CHCl_3).

  12. The use of fluorescence correlation spectroscopy (FCS) as an alternative biomarker detection technique: a preliminary study

    OpenAIRE

    Shahzad, Aamir; Knapp, Martin; Lang, Irene; Köhler, Gottfried

    2011-01-01

    Abstract Biomarkers are essential part of daily medical practice. Currently, biomarkers are being used both for diagnostic and prognostic purposes. There are many approaches e.g. ELISA by which biomarker levels are detected from patient samples. However, all these approaches are laborious, time consuming and expensive. There is therefore a general need for exploring new technique which can overcome these drawbacks. Here, we present a preliminary study for detection of serum biomarkers by fluo...

  13. Diffusion-weighted MR imaging of cystic lesions of neurocysticercosis: a preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Raffin, Luciana S.; Bacheschi, Luiz A.; Machado, Luis R.; Nobrega, Jose P.S.; Coelho, Christina; Leite, Claudia C. [Sao Paulo Univ., SP (Brazil). Faculdade de Medicina. Dept. de Neurologia]. E-mail: bacheschi@henet.usp.br

    2001-12-01

    Neurocysticercosis is an endemic disease in some developing countries. It has pleomorfic clinical and imaging findings, which are variable from patient to patient. In this preliminary note, we studied the magnetic resonance diffusion-weighted images of sixteen patients presenting with cystic lesions of this disease diagnosed by clinical and laboratorial findings. All the lesions had hypointense signal and the similar apparent diffusion coefficient values as the cerebrospinal fluid. (author)

  14. Can anodised zirconium implants stimulate bone formation? Preliminary study in rat model

    OpenAIRE

    Katunar, Maria Rosa; Gomez Sanchez, Andrea Valeria; Ballarre, Josefina; Baca, Matías; Vottola, Carlos; Orellano, Juan C.; Schell, Hanna; Duffo, Gustavo Sergio; Cere, Silvia

    2014-01-01

    Mechanical properties and good biocompatibility of zirconium and some of its alloys focus these materials as good candidates for biomedical applications. The attractive in vivo performance of zirconium is mainly due to the presence of a protective oxide layer. In this preliminary study, surface modification of pure zirconium was made by anodisation in acidic media at low potentials, enhancing the barrier protection given by the oxides and the osseointegration. Electrochemical and SEM (scan...

  15. Transient Galactic Cosmic-ray Modulation during Solar Cycle 24: A Comparative Study of Two Prominent Forbush Decrease Events

    Science.gov (United States)

    Zhao, L.-L.; Zhang, H.

    2016-08-01

    Forbush decrease (FD) events are of great interest for transient galactic cosmic-ray (GCR) modulation study. In this study, we perform comparative analysis of two prominent Forbush events during cycle 24, occurring on 2012 March 8 (Event 1) and 2015 June 22 (Event 2), utilizing the measurements from the worldwide neutron monitor (NM) network. Despite their comparable magnitudes, the two Forbush events are distinctly different in terms of evolving GCR energy spectrum and energy dependence of the recovery time. The recovery time of Event 1 is strongly dependent on the median energy, compared to the nearly constant recovery time of Event 2 over the studied energy range. Additionally, while the evolutions of the energy spectra during the two FD events exhibit similar variation patterns, the spectrum of Event 2 is significantly harder, especially at the time of deepest depression. These difference are essentially related to their associated solar wind disturbances. Event 1 is associated with a complicated shock-associated interplanetary coronal mass ejection (ICME) disturbance with large radial extent, probably formed by the merging of multiple shocks and transient flows, and which delivered a glancing blow to Earth. Conversely, Event 2 is accompanied by a relatively simple halo ICME with small radial extent that hit Earth more head-on.

  16. Blood pressure changes in African American patients receiving chiropractic care in a teaching clinic: a preliminary study

    National Research Council Canada - National Science Library

    McMasters, Kim L; Wang, Joe; York, Jennifer; Hart, John; Neely, Cheneir; Delain, Rochelle J

    2013-01-01

    The purpose of this preliminary study was to determine if a course of chiropractic care would change blood pressure measurements in African American patients and to determine if a study was feasible...

  17. PRELIMINARY PHYTOCHEMICAL ANALYSIS AND ACUTE ORAL TOXICITY STUDY OF MUCUNA PRURIENS LINN. IN ALBINO MICE

    Directory of Open Access Journals (Sweden)

    Deka Manalisha

    2012-02-01

    Full Text Available Mucuna Pruriens Linn. is an annual, climbing shrub which has an important place among aphrodisiac herbs in India since the ancient times. The plant has been using traditionally for many medicinal purposes such as Infertility, Parkinson’s disease, Loss of libido, Antioxidant, Anti venom, Anti microbial etc. The present study was carried out to investigate the preliminary phytochemical analysis and acute oral toxicity of the seeds of M.pruriens on albino mice. Matured seeds of M.pruriens were dried in shed and grinded in a mechanical grinder. The preliminary phytochemical analysis was done by following standard protocols. For acute oral toxicity study, methanolic extract of the seeds were used. The extract was prepared in a Soxlet apparatus. The preliminary phytochemical analysis showed the presence of protein, carbohydrates, glycosides, alkaloids, steroids, flavonoids, phenols and tannins. The acute oral toxicity study showed no mortality up to a dose of 4000 mg per kg body weight. The presence of plant chemicals revealed the medicinal values and the non toxic property of the plant indicated the value of the plant as medicine. Thus, we can conclude that, the seed of the plant can be used as a safe drug against many diseases.

  18. Learning Science Using AR Book: A Preliminary Study on Visual Needs of Deaf Learners

    Science.gov (United States)

    Megat Mohd. Zainuddin, Norziha; Badioze Zaman, Halimah; Ahmad, Azlina

    Augmented Reality (AR) is a technology that is projected to have more significant role in teaching and learning, particularly in visualising abstract concepts in the learning process. AR is a technology is based on visually oriented technique. Thus, it is suitable for deaf learners since they are generally classified as visual learners. Realising the importance of visual learning style for deaf learners in learning Science, this paper reports on a preliminary study of on an ongoing research on problems faced by deaf learners in learning the topic on Microorganisms. Being visual learners, they have problems with current text books that are more text-based that graphic based. In this preliminary study, a qualitative approach using the ethnographic observational technique was used so that interaction with three deaf learners who are participants throughout this study (they are also involved actively in the design and development of the AR Book). An interview with their teacher and doctor were also conducted to identify their learning and medical problems respectively. Preliminary findings have confirmed the need to design and develop a special Augmented Reality Book called AR-Science for Deaf Learners (AR-SiD).

  19. Preliminary study of the Gravimetric Local Geoid Model in Jordan: case study (GeoJordan Model

    Directory of Open Access Journals (Sweden)

    A. Al-Zoubi

    2007-06-01

    Full Text Available Recently, there has been an increased interest in studying and defining the Local and Regional Geoid Model worldwide, due to its importance in geodetic and geophysics applications.The use of the Global Positioning System (GPS is internationally growing, yet the lack of a Geoid Model for Jordan has limited the use of GPS for the geodetic applications in the country. This work aims to present the preliminary results that we propose for «The Gravimetric Jordanian Geoid Model (GeoJordan». The model is created using gravimetric data and the GRAVSOFT program. The model is validated using GPS and precise level measurements in the Amman area. Moreover, we present a comparison using the Global Geopotential Model OSU91A and the EGM96 Model and the results showed great discrepancies. We also present the approach used to obtain the orthometric height from GPS ellipsoidal height measurements. We found that the error margin obtained in this work of the GeoJordan after fitting the data with GPS/leveling measurements is about (10 cm in the tested area whereas the standard error of the created model is about (40 cm.

  20. Transient doping in atomic chains - a case study in time-resolved STM

    Science.gov (United States)

    Snijders, Paul; Polei, Stefan; Erwin, Steve; Himpsel, Franz; Meiwes-Broer, Karl-Heinz; Barke, Ingo

    2014-03-01

    Doping one-dimensional (1D) systems is notoriously difficult due to the structural disorder created by the dopants. The Si(553)-Au surface features an array of step edges with 1D chains of dangling bonds. These chains have a 1x3 ordered ground state. Using a scanning tunneling microscope we inject electrons from the tip into these step-edge chains and we observe that the periodicity of the atomic chains changes from the 1x3 ordered ground state to a 1x2 ordered excited state with increasing tunneling current. The threshold current for this transition is reduced at lower temperatures. In conjunction with first principles density-functional calculations we conclude that the 1x2 phase is created by transient doping of the atom chains. Random telegraph fluctuations between two levels of the tunneling current provide direct access to the dynamics of the phase transition, revealing a monostable state, and lifetimes in the millisecond range. Our method provides a possible avenue to map out a doping-dependent phase diagram in cases where conventional impurity doping is problematic. Research sponsored in part (PCS) by the Division of Materials Sciences and Engineering, Office of Basic Energy Sciences, U.S. Department of Energy.

  1. Timing Studies on X-Per and Discovery of its Transient QPO Feature

    CERN Document Server

    Acuner, Z; Sahiner, S; Serim, M M; Baykal, A; Swank, J

    2014-01-01

    We present timing analysis of RXTE-PCA and INTEGRAL-ISGRI observations of X Per between 1998 and 2010. All pulse arrival times obtained from the RXTE-PCA observations are phase connected and timing solution is obtained using these arrival times. We update long term pulse frequency history of the source by measuring pulse frequencies from RXTE-PCA and INTEGRAL-ISGRI data. From RXTE-PCA data, the relation between frequency derivative and X-ray flux suggests accretion via companion's stellar wind. On the other hand, detection of the transient QPO feature peaking at $\\sim 0.2$ Hz suggests the existence of an accretion disc. From the average intensity power spectra, we find that double break model fits the power spectra well which suggests that the source has at least two different accretion flow components dominating the overall flow. From the power spectra of frequency derivatives, we measure a power law index of $\\sim -1$ which implies that on short time scales disc accretion dominates over noise, while on time...

  2. Cross-correlation spectroscopy study of the transient spark discharge in atmospheric pressure air

    Science.gov (United States)

    Janda, Mário; Hoder, Tomáš; Sarani, Abdollah; Brandenburg, Ronny; Machala, Zdenko

    2017-05-01

    A streamer-to-spark transition in a self-pulsing transient spark (TS) discharge of positive polarity in air was investigated using cross-correlation spectroscopy. The entire temporal evolution of the TS was recorded for several spectral bands and lines: the second positive system of N2 (337.1 nm), the first negative system of {{{{N}}}2}+ (391.4 nm), and atomic oxygen (777.1 nm). The results enable the visualization of the different phases of discharge development including the primary streamer, the secondary streamer, and the transition to the spark. The spatio-temporal distribution of the reduced electric field strength during the primary streamer phase of the TS was determined and discussed. The transition from the streamer to the spark proceeds very fast within about 10 ns for the TS with a current pulse repetition rate in the range 8-10 kHz. This is attributed to memory effects, leading to a low net electron attachment rate and faster propagation of the secondary streamer. Gas heating, accumulation of species such as oxygen atoms from the previous TS pulses, as well as generation of charged particles by stepwise ionization seem to play important roles contributing to this fast streamer-to-spark transition.

  3. CHF Phenomena by Photographic Study of Boiling Behavior due to Transient Heat Inputs

    Directory of Open Access Journals (Sweden)

    Jongdoc Park

    2012-01-01

    Full Text Available The transient boiling heat transfer characteristics in a pool of water and highly wetting liquids such as ethanol and FC-72 due to an exponentially increasing heat input of various rates were investigated using the 1.0 mm diameter experimental heater shaped in a horizontal cylinder for wide ranges of pressure and subcooling. The trend of critical heat flux (CHF values in relation to the periods was divided into three groups. The CHF belonging to the 1st group with a longer period occurs with a fully developed nucleate boiling (FDNB heat transfer process. For the 2nd group with shorter periods, the direct transition to film boiling from non boiling occurs as an explosive boiling. The direct boiling transition at the CHF from non-boiling regime to film boiling occurred without a heat flux increase. It was confirmed that the initial boiling behavior is significantly affected by the property and the wettability of the liquid. The photographic observations on the vapor bubble behavior during transitions to film boiling were performed using a high-speed video camera system.

  4. Theoretical and experimental study of transient response of the Yb-doped fiber amplifier

    Institute of Scientific and Technical Information of China (English)

    Tao Wei; Jianfeng Li; Jianhua Zhu

    2012-01-01

    Some analysis of the transient response of the Yb-doped fiber amplifier are performed by solving a set of time-dependent rate and power transfer equations based on finite-difference method.Meanwhile,the variation of time to reach the steady state for upper level population distribution,the forward and backward amplified spontaneous emissions (ASEs) and stored energy on the system parameters including pump power,fiber length,Yb-doped concentration,and core area are numerically simulated,respectively.The results show that,by optimizing pump pulse width,stored energy can reach or even exceed the steady state value of continuous wave (CW) pump.By increasing Yb-doped concentration and core area,stored energy is increased,the ASE is suppressed and the ASE built-up time is postponed.In addition,the experimental results show the validity of the theoretical ASE built-up time.The obtained results can provide important guiding for the optimization of pump pulse width and fiber parameters.

  5. Asteroid Spin-Rate Study using the Intermediate Palomar Transient Factory

    CERN Document Server

    Chang, Chan-Kao; Lin, Hsing-Wen; Cheng, Yu-Chi; Ngeow, Chow-Choong; Yang, Ting-Chang; Waszczak, Adam; Kulkarni, Shrinivas R; Levitan, David; Sesar, Branimir; Laher, Russ; Surace, Jason; Prince, Thomas A

    2015-01-01

    Two dedicated asteroid rotation-period surveys have been carried out using data taken on January 6-9 and February 20-23 of 2014 by the Intermediate Palomar Transient Factory (iPTF) in the $R$~band with $\\sim 20$-min cadence. The total survey area covered 174~deg$^2$ in the ecliptic plane. Reliable rotation periods for 1,438 asteroids are obtained from a larger data set of 6,551 mostly main-belt asteroids, each with $\\geq 10$~detections. Analysis of 1751, PTF based, reliable rotation periods clearly shows the "spin barrier" at $\\sim 2$~hours for "rubble-pile" asteroids. We also found a new large-sized super-fast rotator, 2005 UW163 (Chang et al., 2014), and other five candidates as well. Our spin-rate distributions of asteroids with $3 < D < 15$~km shows number decrease when frequency greater than 5 rev/day, which is consistent to that of the Asteroid Light Curve Database (LCDB, Warner et al., 2009) and the result of (Masiero et al., 2009). We found the discrepancy in the spin-rate distribution between o...

  6. A study on the two-step transient liquid phase diffusion bonding of K640 superalloy

    Institute of Scientific and Technical Information of China (English)

    Zhang Lei; Hou Jinbao; Zhang Sheng

    2007-01-01

    A new technology, the two-step transient liquid phase diffusion bonding (TLP-DB) technology for cobalt-based K640 superalloy, was investigated. The method consists of a short-time high temperature heating to melt interlayer followed by isothermal solidification of liquid phase at a lower temperature than that of the conventional TLP-DB. The result indicates that the two-step TLP-DB can reliably produce an ideal joint with uniform chemical composition, which is superior to the joint welded by conventional TLP-DB in microstructure and mechanical properties. Bonding parameters of new process are 1 250 ℃ for 0.5 h and 1 180 ℃ for 3 h. The high-temperature tensile strength of the joint by two-step TLP-DB reaches 74% of that of the base material on an equal basis, but the high-temperature tensile strength of the joint by conventional TLP-DB is only 58% of that of the base material.

  7. A study of transient flow turbulence generation during flame/wall interactions in explosions

    Science.gov (United States)

    Hargrave, G. K.; Jarvis, S.; Williams, T. C.

    2002-07-01

    Experimental data are presented for the turbulent velocity field generated during flame/solid wall interactions in explosions. The presence of turbulence in a flammable gas mixture can wrinkle a flame front, increasing the flame surface area and enhancing the burning rate. In congested process plant, any flame propagating through an accidental release of flammable mixture will encounter obstructions in the form of walls, pipe-work or storage vessels. The interaction between the gas movement and the obstacle creates turbulence by vortex shedding and local wake/recirculation, whereby the flame can be wrapped in on itself, increasing the surface area available for combustion. Particle image velocimetry (PIV) was used to characterize the turbulent flow field in the wake of the obstacles placed in the path of propagating flames. This allowed the quantification of the interaction of the propagating flame and the generated turbulent flow field. Due to the accelerating nature of the explosion flow field, the wake flows develop `transient' turbulent fields and PIV provided data to define the spatial and temporal variation of the velocity field ahead of the propagating flame, providing an understanding of the direct interaction between flow and flame.

  8. Uncertainty and Sensitivity Studies with TRACE-SUSA and TRACE-DAKOTA by Means of Transient BFBT Data

    Directory of Open Access Journals (Sweden)

    Wadim Jaeger

    2013-01-01

    Full Text Available In the present paper, an uncertainty and sensitivity study is performed for transient void fraction and pressure drop measurements. Two transients have been selected from the NUPEC BFBT database. The first one is a turbine trip without bypass and the second one is a trip of a recirculation pump. TRACE (version 5.0 patch 2 is used for the thermohydraulic study and SUSA and DAKOTA are used for the quantification of the model uncertainties and the evaluation of the sensitivities. As uncertain parameters geometrical values, hydraulic diameter, and wall roughness are considered while mass flow rate, power, pressure, and inlet subcooling (inlet temperature are chosen as boundary and input conditions. Since these parameters change with time, it is expected that the importance of them on pressure drop and void fraction will change, too. The results show that the pressure drop is mostly sensitive to geometrical variations like the hydraulic diameter and the form loss coefficient of the spacer grid. For low void fractions, the parameter of the highest importance is the inlet temperature/subcooling while at higher void fraction the power is also of importance.

  9. Transient analysis of subcritical/supercritical carbon dioxide based natural circulation loop with end heat exchangers: experimental study

    Science.gov (United States)

    Yadav, Ajay Kumar; Ramgopal, Maddali; Bhattacharyya, Souvik

    2017-09-01

    Carbon dioxide (CO2) based natural circulation loops (NCLs) has gained attention due to its compactness with higher heat transfer rate. In the present study, experimental investigations have been carried out to capture the transient behaviour of a CO2 based NCL operating under subcritical as well as supercritical conditions. Water is used as the external fluid in cold and hot heat exchangers. Results are obtained for various inlet temperatures (323-353 K) of water in the hot heat exchanger and a fixed inlet temperature (305 K) of cooling water in the cold heat exchanger. Effect of loop operating pressure (50-90 bar) on system performance is also investigated. Effect of loop tilt in two different planes (XY and YZ) is also studied in terms of transient as well as steady state behaviour of the loop. Results show that the time required to attain steady state decreases as operating pressure of the loop increases. It is also observed that the change in temperature of loop fluid (CO2) across hot or cold heat exchanger decreases as operating pressure increases.

  10. Comparative Study of Time-Frequency Decomposition Techniques for Fault Detection in Induction Motors Using Vibration Analysis during Startup Transient

    Directory of Open Access Journals (Sweden)

    Paulo Antonio Delgado-Arredondo

    2015-01-01

    Full Text Available Induction motors are critical components for most industries and the condition monitoring has become necessary to detect faults. There are several techniques for fault diagnosis of induction motors and analyzing the startup transient vibration signals is not as widely used as other techniques like motor current signature analysis. Vibration analysis gives a fault diagnosis focused on the location of spectral components associated with faults. Therefore, this paper presents a comparative study of different time-frequency analysis methodologies that can be used for detecting faults in induction motors analyzing vibration signals during the startup transient. The studied methodologies are the time-frequency distribution of Gabor (TFDG, the time-frequency Morlet scalogram (TFMS, multiple signal classification (MUSIC, and fast Fourier transform (FFT. The analyzed vibration signals are one broken rotor bar, two broken bars, unbalance, and bearing defects. The obtained results have shown the feasibility of detecting faults in induction motors using the time-frequency spectral analysis applied to vibration signals, and the proposed methodology is applicable when it does not have current signals and only has vibration signals. Also, the methodology has applications in motors that are not fed directly to the supply line, in such cases the analysis of current signals is not recommended due to poor current signal quality.

  11. Myelin Water Fraction Is Transiently Reduced after a Single Mild Traumatic Brain Injury--A Prospective Cohort Study in Collegiate Hockey Players.

    Directory of Open Access Journals (Sweden)

    Alexander D Wright

    Full Text Available Impact-related mild traumatic brain injuries (mTBI are a major public health concern, and remain as one of the most poorly understood injuries in the field of neuroscience. Currently, the diagnosis and management of such injuries are based largely on patient-reported symptoms. An improved understanding of the underlying pathophysiology of mTBI is urgently needed in order to develop better diagnostic and management protocols. Specifically, dynamic post-injury changes to the myelin sheath in the human brain have not been examined, despite 'compromised white matter integrity' often being described as a consequence of mTBI. In this preliminary cohort study, myelin water imaging was used to prospectively evaluate changes in myelin water fraction, derived from the T2 decay signal, in two varsity hockey teams (45 players over one season of athletic competition. 11 players sustained a concussion during competition, and were scanned at 72 hours, 2 weeks, and 2 months post-injury. Results demonstrated a reduction in myelin water fraction at 2 weeks post-injury in several brain areas relative to preseason scans, including the splenium of the corpus callosum, right posterior thalamic radiation, left superior corona radiata, left superior longitudinal fasciculus, and left posterior limb of the internal capsule. Myelin water fraction recovered to pre-season values by 2 months post-injury. These results may indicate transient myelin disruption following a single mTBI, with subsequent remyelination of affected neurons. Myelin disruption was not apparent in the athletes who did not experience a concussion, despite exposure to repetitive subconcussive trauma over a season of collegiate hockey. These findings may help to explain many of the metabolic and neurological deficits observed clinically following mTBI.

  12. Cooling via one hand improves physical performance in heat-sensitive individuals with Multiple Sclerosis: A preliminary study

    Directory of Open Access Journals (Sweden)

    Murray Julie

    2008-05-01

    Full Text Available Abstract Background Many individuals afflicted with multiple sclerosis (MS experience a transient worsening of symptoms when body temperature increases due to ambient conditions or physical activity. Resulting symptom exacerbations can limit performance. We hypothesized that extraction of heat from the body through the subcutaneous retia venosa that underlie the palmar surfaces of the hands would reduce exercise-related heat stress and thereby increase the physical performance capacity of heat-sensitive individuals with MS. Methods Ten ambulatory MS patients completed one or more randomized paired trials of walking on a treadmill in a temperate environment with and without cooling. Stop criteria were symptom exacerbation and subjective fatigue. The cooling treatment entailed inserting one hand into a rigid chamber through an elastic sleeve that formed an airtight seal around the wrist. A small vacuum pump created a -40 mm Hg subatmospheric pressure enviinside the chamber where the palmar surface of the hand rested on a metal surface maintained at 18–22°C. During the treatment trials, the device was suspended from above the treadmill on a bungee cord so the subjects could comfortably keep a hand in the device without having to bear its weight while walking on the treadmill. Results When the trials were grouped by treatment only, cooling treatment increased exercise durations by 33% (43.6 ± 17.1 min with treatment vs. 32.8 ± 10.9 min. without treatment, mean ± SD, p -6, paired t-test, n = 26. When the average values were calculated for the subjects who performed multiple trials before the treatment group results were compared, cooling treatment increased exercise duration by 35% (42.8 ± 16.4 min with treatment vs. 31.7 ± 9.8 min. without treatment, mean ± SD, p Conclusion These preliminary results suggest that utilization of the heat transfer capacity of the non-hairy skin surfaces can enable temperature-sensitive individuals with MS to

  13. Preliminary Study on Management of Agricultural Scientific Research Projects in the New Situation

    Institute of Scientific and Technical Information of China (English)

    Haiyan LUO; Qingqun YAO; Lizhen CHEN; Yu ZHENG

    2015-01-01

    Project management of agricultural scientific research institutions is an important section of agricultural scientific research plan management. It is of great significance for sustainable development of scientific research work of scientific research institutions. According to a series of opinions and notices about scientific and technological system reform issued by the state,and combining current situations of management of scientific research projects in scientific research institutions,this paper made a preliminary study on management of agricultural scientific research projects in the new trend. Finally,on the basis of the current situations of management of agricultural scientific research projects,it came up with pertinent recommendations,including strengthening communication and cooperation and actively declaring projects,strengthening preliminary planning of projects and establishing project information database,reinforcing project process management,ensuring on-time and high quality completion of projects,and strengthening learning and improving quality of management personnel.

  14. Preliminary results of an extensive study of fragmentation measurements for medical and space applications

    CERN Document Server

    Agodi, C; Calabretta, L; Cirrone, G A P C; Cuttone, G; De Napoli, M; Fiorini, F; Giacoppo, F; Mairani, A; Morone, M C; Patera, V; Raciti, G; Rapisarda, E; Ricciardi, V; Romano, F; Sala, P; Sciubba, A

    2010-01-01

    Here we report on preliminary results of an extensive study of fragmentation cross sections measurements useful for medical and space applications. In particular, we looked at the hadrontherapy and space radiation research. Indeed, the measure of fragmentation cross sections is an important information to estimate how this process modifies dose distributions and biological effectiveness, both inside human body and spacecraft. In this picture we started to measure the fragmentation of 12C beam accelerated by the Superconducting Cyclotron at 32 AMeV, 62 AMeV on 12C, 207Pb and 197Au at the INFN Laboratory Nazionali del Sud in Catania (Italy). Preliminary comparison between absolute cross-sections measured for the systems: 12C+207Pb at 32AMeV and for 12C+197Au at 62AMeV is performed.

  15. Preliminary study on enhancing waste management best practice model in Malaysia construction industry

    Science.gov (United States)

    Jamaludin, Amril Hadri; Karim, Nurulzatushima Abdul; Noor, Raja Nor Husna Raja Mohd; Othman, Nurulhidayah; Malik, Sulaiman Abdul

    2017-08-01

    Construction waste management (CWM) is the practice of minimizing and diverting construction waste, demolition debris, and land-clearing debris from disposal and redirecting recyclable resources back into the construction process. Best practice model means best choice from the collection of other practices that was built for purpose of construction waste management. The practice model can help the contractors in minimizing waste before the construction activities will be started. The importance of minimizing wastage will have direct impact on time, cost and quality of a construction project. This paper is focusing on the preliminary study to determine the factors of waste generation in the construction sites and identify the effectiveness of existing construction waste management practice conducted in Malaysia. The paper will also include the preliminary works of planned research location, data collection method, and analysis to be done by using the Analytical Hierarchy Process (AHP) to help in developing suitable waste management best practice model that can be used in the country.

  16. Sodium alginate as an ideal submucosal injection material for endoscopic submucosal resection: preliminary experimental and clinical study.

    Science.gov (United States)

    Akagi, Tomonori; Yasuda, Kazuhiro; Tajima, Masaaki; Suzuki, Kosuke; Inomata, Masafumi; Shiraishi, Norio; Sato, Yuhki; Kitano, Seigo

    2011-11-01

    Sodium alginate is used clinically in the treatment of peptic ulcer disease. Because of its viscosity, sodium alginate could possibly become a new submucosal injection material for use in endoscopic resection. We evaluated the feasibility of endoscopic submucosal dissection (ESD) using sodium alginate. The lesion-lifting properties of sodium alginate were examined in porcine stomachs and were compared with those of normal saline solution and sodium hyaluronate solution. After confirming the proper concentration of sodium alginate, ESD using sodium alginate was performed in 11 patients with gastric mucosal cancer or adenoma. The lesion-lifting properties of sodium alginate and clinical outcomes were assessed. The thickness of the submucosal elevation created by 3% sodium alginate in porcine stomach was equivalent to that of sodium hyaluronate. ESD using sodium alginate was completed successfully in all patients without adverse effects except in 1 patient in whom transient shrinkage of the gastric wall disappeared spontaneously after approximately 30 minutes. The mean tumor size was 15.3 mm. En bloc resection and a negative resection margin were obtained in all. Histopathologic examination revealed that all tumors were confined to the mucosal layer except for 1 that was confined to the submucosal layer without lymphovascular invasion, and there were no adverse effects such as tissue damage. No patient required additional treatment, and none showed recurrence during a median follow-up period of 28 months. Small sample size. This preliminary study suggests that sodium alginate might be a novel, safe submucosal injection material for use in endoscopic resection. Further investigation of the properties of sodium alginate is warranted. Copyright © 2011 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

  17. A qualitative study exploring patients' experiences of standard care or cardiac rehabilitation post minor stroke and transient ischaemic attack.

    Science.gov (United States)

    Hillsdon, Kaye M; Kersten, Paula; Kirk, Hayden J S

    2013-09-01

    To explore individuals' experiences of receiving either standard care or comprehensive cardiac rehabilitation post minor stroke or transient ischaemic attack. A qualitative study using semi-structured interviews, alongside a randomized controlled trial, exploring the effectiveness of comprehensive cardiac rehabilitation compared with standard care. Interviews were transcribed verbatim and subjected to thematic analysis. Individuals' homes. People who have experienced a minor stroke or transient ischaemic attack and who were partaking in a secondary prevention randomized controlled trial (6-7 months post the event, 17 males, five females; mean age 67 years). Not relevant. Not relevant. Four themes were identified: information delivery, comparing oneself with others, psychological impact, attitudes and actions regarding risk factor reduction. Participants indicated a need for improved information delivery, specific to their own risk factors and lifestyle changes. Many experienced psychological impact as a result of their minor stroke. Participants were found to make two types of social comparison; the comparison of self to another affected by stroke, and the comparison of self to cardiac patients. Comprehensive cardiac rehabilitation was reported to have positive effects on people's motivation to exercise. Following a minor stroke, many individuals do not recall information given or risk factors specific to them. Downward comparison with individuals who have had a cardiovascular event led to some underplaying the significance of their minor stroke.

  18. Impact Study of PMSG-Based Wind Power Penetration on Power System Transient Stability Using EEAC Theory

    Directory of Open Access Journals (Sweden)

    Zhongyi Liu

    2015-11-01

    Full Text Available Wind turbines with direct-driven permanent magnet synchronous generators (PMSGs are widely used in wind power generation. According to the dynamic characteristics of PMSGs, an impact analysis of PMSG-based wind power penetration on the transient stability of multi-machine power systems is carried out in this paper based on the theory of extended equal area criterion (EEAC. Considering the most severe PMSG integration situation, the changes in the system’s equivalent power-angle relationships after integrating PMSGs are studied in detail. The system’s equivalent mechanical input power and the fault period electrical output power curves are found to be mainly affected. The analysis demonstrates that the integration of PMSGs can cause either detrimental or beneficial effects on the system transient stability. It is determined by several factors, including the selection of the synchronous generators used to balance wind power, the reactive power control mode of PMSGs and the wind power penetration level. Two different simulation systems are also adopted to verify the analysis results.

  19. An induction machine model including interbar currents for studying performances during transients and steady state

    Energy Technology Data Exchange (ETDEWEB)

    Razik, H. [Universite Henri Poincare, GREEN, CNRS-UMR 7037, BP 239, F-54506 Vandoeuvre-les-Nancy Cedex (France); Henao, H. [University of Picardie, CREA, 33 rue Saint Leu, F-80039 Amiens Cedex 1 (France); Carlson, R. [GRUCAD/CTC/UFSC, Campus Universitario, C.P. 436, Florianopolis - SC, 88040-900 (Brazil)

    2009-01-15

    This paper presents a mathematical model of a three-phase induction motor taking into consideration the interbar contacts. Several models have been available in the references. However, they consider the rotor of the induction motor as being constituted either a three-phase or a squirrel cage even if it operates under stator and/or rotor faults condition. Nonetheless, the contact between a bar and the iron core for the machine has to be considered, especially when a rotor fault occurs. It is obvious that rotor currents are under the influence of rotor constitution materials. So, the paper aim's concerns a transient model of the induction motors which can consider the rotor broken bars defect. Despite its increasing complexity, it could be able to provide with useful indications for diagnostic purposes. This model is advocated for the simulation of motors behavior under rotor defect which takes into account the interbar currents. The proposed technique is based on the mesh model analysis of the squirrel cage. As low power induction motors are prevalent in industrial plants, we pay a special attention on them. Notwithstanding, additional currents are due to the contact between the non-insulated bar constituting the squirrel cage to the rotor iron core. The monitoring of induction motors is predominantly made through the stator current analysis of the motor when it operates at nominal condition. Moreover, this one is observed in steady state operating system, knowing that the motor is generally fed by a sinusoidal supply. Consequently, simulation results showed in this paper prove the effectiveness of the proposed approach, and the impact of interbar resistance both on the model and the line current spectrum for the diagnostic. An experimental test proves the effectiveness of this model. (author)

  20. Supergiant Fast X-ray Transients: A Case Study for LOFT

    Science.gov (United States)

    Romano, Patrizia; Mangano, V.; Bozzo, E.; Esposito, P.; Ferrigno, C.

    2013-04-01

    LOFT, the Large Observatory For X-ray Timing, is a new space mission concept selected by ESA in February 2011 and currently competing for a launch of opportunity in 2022. LOFT will carry a coded mask Wide Field Monitor (WFM) and a 10-m^2 class collimated X-ray Large Area Detector (LAD) operating in the energy range 2-80 keV. The instruments on-board LOFT will dramatically deepen our knowledge of Supergiant Fast X-ray Transients, a class of High-Mass X-ray Binaries whose optical counterparts are O or B supergiant stars, and whose X-ray outbursts are about 4 orders of magnitude brighter than the quiescent state. The LAD and the WFM will provide simultaneous high S/N broad-band and time-resolved spectroscopy in several intensity states, long term monitoring that will yield new determinations of orbital periods, as well as spin periods. We show the results of an extensive set of simulations based on the Swift broad-band and detailed XMM-Newton observations we collected up to now. Our simulations describe the outbursts at several intensities (F(2-10 keV)=5.9E-9 to 5.5E-10 erg cm-2 s-1), the intermediate and most common state (1E-11 erg cm-2 s-1), and the low state (1.2E-12 to 5E-13 erg cm-2 s-1). We also considered large variations of NH and the presence of emission lines, as observed by Swift and XMM-Newton. We acknowledge financial contribution from ASI-INAF I/004/11/0 and I/021/12/0.

  1. Transient W-band EPR study of sequential electron transfer in photosynthetic bacterial reaction centers

    Energy Technology Data Exchange (ETDEWEB)

    Tang, J.; Utschig, L.M.; Poluektov, O.; Thurnauer, M.C. [Argonne National Lab., IL (United States). Chemistry Div.

    1999-06-17

    The key reaction of photosynthetic solar energy conversion involves the photoexcitation of a primary donor (P) followed by rapid, sequential electron transfer to a series of acceptors resulting in charge separation. Electron-spin polarized (ESP) EPR spectra at W-band (95 GHz) were obtained for deuterated Fe-removed/Zn-substituted photosynthetic bacterial reaction centers (RCs) to investigate the influence of the rate of charge separation on the observed P{sup +}Q{sub A}{sup {minus}} charge separated state. Temperature dependent ESP EPR spectra for kinetically characterized Zn-substituted RCs from Rb. sphaeroides R-26 having different rates (k{sub Q}) of the electron transfer from the bacteriopheophytin to the quinone acceptor were obtained. The Zn-RCs exhibited either the native fast (200 ps){sup {minus}1} k{sub Q} or a slow (3--6 ns){sup {minus}1} k{sub Q} at 298 K as determined from transient optical measurements. Sequential electron-transfer polarization modeling of the polarized W-band EPR spectra obtained with these samples was used to address the reason for the differences in the electron-transfer rates. Here, the authors report the k{sub Q} rate constant, the temperature dependence of k{sub Q}, and the reorganization energy for the P{sup +}H{sup {minus}}Q{sub A} and P{sup +}HQ{sub A}{sup {minus}} electron-transfer step determined from SETP modeling of the experimental spectra. The reorganization energy for the electron-transfer process between P{sup +}H{sup {minus}}Q{sub A} and P{sup +}HQ{sub A}{sup {minus}}, and not structural changes in the donor or acceptor, was found to be the dominant factor that is altered during Fe-removal procedures.

  2. Blade system design studies volume II : preliminary blade designs and recommended test matrix.

    Energy Technology Data Exchange (ETDEWEB)

    Griffin, Dayton A. (Global Energy Concepts, LLC, Kirkland, WA)

    2004-06-01

    As part of the U.S. Department of Energy's Wind Partnerships for Advanced Component Technologies (WindPACT) program, Global Energy Concepts, LLC is performing a Blade System Design Study (BSDS) concerning innovations in materials, processes and structural configurations for application to wind turbine blades in the multi-megawatt range. The BSDS Volume I project report addresses issues and constraints identified to scaling conventional blade designs to the megawatt size range, and evaluated candidate materials, manufacturing and design innovations for overcoming and improving large blade economics. The current report (Volume II), presents additional discussion of materials and manufacturing issues for large blades, including a summary of current trends in commercial blade manufacturing. Specifications are then developed to guide the preliminary design of MW-scale blades. Using preliminary design calculations for a 3.0 MW blade, parametric analyses are performed to quantify the potential benefits in stiffness and decreased gravity loading by replacement of a baseline fiberglass spar with carbon-fiberglass hybrid material. Complete preliminary designs are then presented for 3.0 MW and 5.0 MW blades that incorporate fiberglass-to-carbon transitions at mid-span. Based on analysis of these designs, technical issues are identified and discussed. Finally, recommendations are made for composites testing under Part I1 of the BSDS, and the initial planned test matrix for that program is presented.

  3. Preliminary experimental results on studying possibility of variable mass liner (VML) formation

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-31

    The main objective of the present experiment was to study the formation process and initial stage of acceleration of a variable-mass plasma liner (VML). The method is based on magnetic acceleration of a liner with the mass reduced during such acceleration. The experiment was carried out on February 16 at VNIIEF. This report describes the results of measurements obtained in the experiment and preliminary analysis of the results characterizing operation of the test facility main units: helical EMG; 5-module disk EMG 400 mm in diameter (DEMG); ponderomotive unit (PU) with a cylindric condensed liner and a special tooth-cutoff. The first part of the report presents measurement results obtained on the VNIIEF`s diagnostic equipment that are compared with those obtained by American specialists on their diagnostic equipment. Information submitted by American specialists is included in part 2 of this report. The second part of the report presents preliminary computational-theoretic analysis of the main measured results describing operation of DEMG TL system in the experiment; experimental data are compared with theoretical ones obtained before and after the experiment. But more emphasis is placed on the data preliminary analysis indicating that in the experiment a variable mass liner is formed (VML or plasma bubble).

  4. The MSFC Collaborative Engineering Process for Preliminary Design and Concept Definition Studies

    Science.gov (United States)

    Mulqueen, Jack; Jones, David; Hopkins, Randy

    2011-01-01

    This paper describes a collaborative engineering process developed by the Marshall Space Flight Center's Advanced Concepts Office for performing rapid preliminary design and mission concept definition studies for potential future NASA missions. The process has been developed and demonstrated for a broad range of mission studies including human space exploration missions, space transportation system studies and in-space science missions. The paper will describe the design team structure and specialized analytical tools that have been developed to enable a unique rapid design process. The collaborative engineering process consists of integrated analysis approach for mission definition, vehicle definition and system engineering. The relevance of the collaborative process elements to the standard NASA NPR 7120.1 system engineering process will be demonstrated. The study definition process flow for each study discipline will be will be outlined beginning with the study planning process, followed by definition of ground rules and assumptions, definition of study trades, mission analysis and subsystem analyses leading to a standardized set of mission concept study products. The flexibility of the collaborative engineering design process to accommodate a wide range of study objectives from technology definition and requirements definition to preliminary design studies will be addressed. The paper will also describe the applicability of the collaborative engineering process to include an integrated systems analysis approach for evaluating the functional requirements of evolving system technologies and capabilities needed to meet the needs of future NASA programs.

  5. Preliminary assessment of the Long Island National Wildlife Refuge Complex environmental contaminants background study: Fifth year results

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report represents the preliminary results of the fifth year of the multiyear study entitled, "The Long Island National Wildlife Refuge Complex (Complex)...

  6. Application of High-Speed Infrared Imaging to Study Transient Joule Heating in Station Class Zinc Oxide Surge Arresters

    Energy Technology Data Exchange (ETDEWEB)

    Dinwiddie, R. B.; Wang, H.; Johnnerfelt, B.

    2004-03-15

    Zinc Oxide based surge arresters are widely used to safeguard and improve reliability of the electrical power delivering and transmission systems. The primary application of surge arresters is to protect valuable components such as transformers from lightning strikes and switching transients in the transmission lines. Metal-oxide-varistor blocks (MOV, e.g. ZnO) are used in surge arrester assemblies. ORNL has developed an advanced infrared imaging technique to monitor the joule heating during transient heating of small varistors. In a recent short-term R&D effort, researchers from ABB and ORNL have expanded the use of IR imaging to larger station-class arrester blocks. An on-site visit to the ABB facility demonstrated that the use of IR imaging is not only feasible but also has the potential to improve arrester quality and reliability. The ASEA Brown Bower (ABB) Power and Technology & Development Company located at Greensburg PA having benefited from collaborative R&D cooperation with ORNL. ABB has decided a follow-on CRADA project is very important. While the previous efforts to study surge arresters included broader studies of IR imaging and computer modeling, ABB has recognized the potential of IR imaging, decided to focus on this particular area. ABB plans to use this technique to systematically study the possible defects in the arrester fabrication process. ORNL will improve the real-time monitoring capability and provide analysis of the infrared images. More importantly, the IR images will help us understand transient heating in a ceramic material from the scientific standpoint. With the improved IR imaging ABB and ORNL will employ the IR system to visualize manufacturing defects that could not be detected otherwise. The proposed on-site tests at ABB Power Technology & Development processing facility will identify the defects and also allow quick adjustments to be made since the resulting products can be inspected immediately. ABB matched the DOE $50K funding

  7. Preliminary study of PCBs in raccoons living on or near the Paducah Gaseous Diffusion Plant, Kentucky

    Energy Technology Data Exchange (ETDEWEB)

    Halbrook, Richard S. [Southern Illinois Univ., Carbondale, IL (United States). Dept. of Zoology. Cooperative Wildlife Research Lab. Kentucky Research Consortium for Energy and Environment

    2016-01-15

    The “Ecological Monitoring at the Paducah Gaseous Diffusion Plant: Historical Evaluation and Guidelines for Future Monitoring” report (Halbrook, et al. 2007) recommended the raccoon as a species for study at the Paducah Gaseous Diffusion Plant (PGDP). This species was selected to fill data gaps in ecological resources and provide resource managers with knowledge that will be valuable in making decisions and implementing specific actions to safeguard ecological resources and reduce human exposure. The current paper reports results of a preliminary evaluation to establish protocols for collection of tissues and initial screening of polychlorinated biphenyls (PCBs) in raccoons collected near the PGDP. These data are useful in developing future more comprehensive studies.

  8. Study on the Cross Plane Thermal Transport of Polycrystalline Molybdenum Nanofilms by Applying Picosecond Laser Transient Thermoreflectance Method

    Directory of Open Access Journals (Sweden)

    Tingting Miao

    2014-01-01

    Full Text Available Thin metal films are widely used as interconnecting wires and coatings in electronic devices and optical components. Reliable thermophysical properties of the films are required from the viewpoint of thermal management. The cross plane thermal transport of four polycrystalline molybdenum nanofilms with different thickness deposited on glass substrates has been studied by applying the picosecond laser transient thermoreflectance technique. The measurement is performed by applying both front pump-front probe and rear pump-front probe configurations with high quality signal. The determined cross plane thermal diffusivity of the Mo films greatly decreases compared to the corresponding bulk value and tends to increase as films become thicker, exhibiting significant size effect. The main mechanism responsible for the thermal diffusivity decrease of the present polycrystalline Mo nanofilms is the grain boundary scattering on the free electrons. Comparing the cross plane thermal diffusivity and inplane electrical conductivity indicates the anisotropy of the transport properties of the Mo films.

  9. Transient bond scission of polytetrafluoroethylene under laser-induced shock compression studied by nanosecond time-resolved Raman spectroscopy

    Science.gov (United States)

    Nakamura, Kazutaka; Wakabayashi, Kunihiko; Konodo, Ken-Ichi

    2001-06-01

    Nanosecond time-resolved Raman spectroscopy has been performed to study polymer films, polytetrafluoroethylene (PTFE), under laser driven shock compression at laser power density of 4.0 GW/cm^2. The overtone-mode line of PTFE showed red shift (18 cm-1) at delay time of 9.3 ns due to the shock compression and corresponding pressure was estimated to be approximately 2.7 GPa by analyzing static and shock compression data. The estimated pressure was in good agreement with that estimated by ablation pressure in glass-confined geometry. A new vibrational line at 1900 cm-1 appeared only under shock compression and was assigned to the C=C streching in transient species such as a monomer (C_2F_4) produced by the shock-induced bond scission. Intensity of the new line increased with increasing delay time along propagation of the shock compression with a shock velocity of 2.5 km/s.

  10. Transient Ischemic Attack

    Medline Plus

    Full Text Available Transient Ischemic Attack TIA , or transient ischemic attack, is a "mini stroke" that occurs when a blood ... The only difference between a stroke and TIA is that with TIA the blockage is transient (temporary). ...

  11. A preliminary model to avoid the overestimation of sample size in bioequivalence studies.

    Science.gov (United States)

    Ramírez, E; Abraira, V; Guerra, P; Borobia, A M; Duque, B; López, J L; Mosquera, B; Lubomirov, R; Carcas, A J; Frías, J

    2013-02-01

    Often the only available data in literature for sample size estimations in bioequivalence studies is intersubject variability, which tends to result in overestimation of sample size. In this paper, we proposed a preliminary model of intrasubject variability based on intersubject variability for Cmax and AUC data from randomized, crossovers, bioequivalence (BE) studies. From 93 Cmax and 121 AUC data from test-reference comparisons that fulfilled BE criteria, we calculated intersubject variability for the reference formulation and intrasubject variability from ANOVA. Lineal and exponential models (y=a(1-e-bx)) were fitted weighted by the inverse of the variance, to predict the intrasubject variability based on intersubject variability. To validate the model we calculated the coefficient of cross-validation of data from 30 new BE studies. The models fit very well (R2=0.997 and 0.990 for Cmax and AUC respectively) and the cross-validation correlation were 0.847 for Cmax and 0.572 for AUC. A preliminary model analyses allow us to estimate the intrasubject variability based on intersubject variability for sample size calculation purposes in BE studies. This approximation provides an opportunity for sample size reduction avoiding unnecessary exposure of healthy volunteers. Further modelling studies are desirable to confirm these results especially suggestions of the higher intersubject variability range.

  12. The cost of child health inequalities in Aotearoa New Zealand: a preliminary scoping study

    Directory of Open Access Journals (Sweden)

    Mills Clair

    2012-05-01

    Full Text Available Abstract Background Health inequalities have been extensively documented, internationally and in New Zealand. The cost of reducing health inequities is often perceived as high; however, recent international studies suggest the cost of “doing nothing” is itself significant. This study aimed to develop a preliminary estimate of the economic cost of health inequities between Māori (indigenous and non-Māori children in New Zealand. Methods Standard quantitative epidemiological methods and “cost of illness” methodology were employed, within a Kaupapa Māori theoretical framework. Data were obtained from national data collections held by the New Zealand Health Information Service and other health sector agencies. Results Preliminary estimates suggest child health inequities between Māori and non-Māori in New Zealand are cost-saving to the health sector. However the societal costs are significant. A conservative “base case” scenario estimate is over $NZ62 million per year, while alternative costing methods yield larger costs of nearly $NZ200 million per annum. The total cost estimate is highly sensitive to the costing method used and Value of Statistical Life applied, as the cost of potentially avoidable deaths of Māori children is the major contributor to this estimate. Conclusions This preliminary study suggests that health sector spending is skewed towards non-Māori children despite evidence of greater Māori need. Persistent child health inequities result in significant societal economic costs. Eliminating child health inequities, particularly in primary care access, could result in significant economic benefits for New Zealand. However, there are conceptual, ethical and methodological challenges in estimating the economic cost of child health inequities. Re-thinking of traditional economic frameworks and development of more appropriate methodologies is required.

  13. The MWA Transients Survey (MWATS).

    Science.gov (United States)

    Bell, M.; Murphy, T.; Kaplan, D. L.; Croft, S. D.; Hancock, P.; Rowlinson, A.; Wayth, R.; Gaensler, B.; Hurley-Walker, N.; Offringa, A.; Loi, C.; Bannister, K.; Trott, C.; Marquart, J.

    2017-01-01

    We propose the continuation of the MWA transients survey to search for and monitor low frequency transient and variable radio sources in the southern sky. This proposal is aimed at commensally utilising data from the GLEAM-X (G0008) project in semester 2017-A. The aim of this commensal data acquisition is to commission long baseline observations for transient science. In particular this will involve studying the impact of the ionosphere on calibration and imaging, and developing the techniques needed to produce science quality data products. The proposed drift scans with LST locking (see G0008 proposal) are particularly exciting as we can test image subtraction for transient and variable identification. This survey is targeted at studying objects such as AGN (intrinsic and extrinsic variability), long duration synchrotron emitters, pulsars and transients of unknown origin. The maps generated from this survey will be analysed with the Variables and Slow Transients (VAST) detection pipeline. The motivation for this survey is as follows: (i) To obtain temporal data on an extremely large and robust sample of low frequency sources to explore and quantify both intrinsic and extrinsic variability; (ii) To search and find new classes of low frequency radio transients that previously remained undetected and obscured from multi-wavelength discovery; (iii) To place rigorous statistics on the occurrence of both transients and variables prior to the Australian SKA era.

  14. On Detecting Transients

    CERN Document Server

    Belanger, G

    2013-01-01

    Transient phenomena are interesting and potentially highly revealing of details about the processes under observation and study that could otherwise go unnoticed. It is therefore important to maximise the sensitivity of the method used to identify such events. In this article we present a general procedure based on the use of the likelihood function for identifying transients that is particularly suited for real-time applications because it requires no grouping or pre-processing of the data. The method is optimal in the sense that all the information that is available in the data is used in the statistical decision making process, and is suitable for a wide range of applications. We here consider those most common in astrophysics which involve searching for transient sources, events or features in images, time series, energy spectra and power spectra, and demonstrate the use of the method in the cases of a transient in a time series or in a power spectrum. We derive a fit statistic that is ideal for fitting a...

  15. Land-use conflicts in The Geysers-Calistoga KGRA: a preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    O' Banion, K.; Hall, C.; Haven, K.

    1979-12-01

    This preliminary study of potential land use conflicts of geothermal development in The Geysers region, one component of the LLL/LBL socioeconomic program, focuses on Lake County because it has most of the undeveloped resource and the least regulatory capability. The land resource is characterized in terms of its ecological, hydrological, agricultural, and recreational value; intrinsic natural hazards; and the adequacy of roads and utility systems and each factor is depicted on a map. Then those factors are analyzed for potential conflicts with both geothermal and urban development and the conflicts displayed on respective maps. A brief review of laws and methods germane to geothermal land-use regulation is included.

  16. A Preliminary Study on 1D Numerical Experiment of Water Debris Flow in Gully

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    In order to improve and enhance the numerical modeling methods and its application on debris flow problems,a preliminary study has been proposed in accordance with the corrected water-sediment numerical model on the premise of revised resistance and sediment capacity equations.Firstly,an overview the recent re- search achievements on numerical simulation of debris flow has been conducted,the results shown that a gener- al numerical model for debris flow can not be existed at all because the complex rheol...

  17. Effects of implant angulation, material selection, and impression technique on impression accuracy: a preliminary laboratory study.

    Science.gov (United States)

    Rutkunas, Vygandas; Sveikata, Kestutis; Savickas, Raimondas

    2012-01-01

    The aim of this preliminary laboratory study was to evaluate the effects of 5- and 25-degree implant angulations in simulated clinical casts on an impression's accuracy when using different impression materials and tray selections. A convenience sample of each implant angulation group was selected for both open and closed trays in combination with one polyether and two polyvinyl siloxane impression materials. The influence of material and technique appeared to be significant for both 5- and 25-degree angulations (P impression accuracy. The open-tray technique was more accurate with highly nonaxially oriented implants for the small sample size investigated.

  18. Sensorized pacifier to quantify the rhythmicity of non-nutritive sucking: A preliminary study on newborns.

    Science.gov (United States)

    Grassi, A; Cecchi, F; Guzzetta, A; Laschi, C

    2015-01-01

    Non-nutritive sucking (NNS) is one of the most significant spontaneous actions of infants. The suction/expression rhythmicity of NNS remains unknown. We developed a sensorized pacifier for an objective measurement of NNS. Two miniaturized digital pressure sensors are embedded into a commercial pacifier and they acquired suction and expression pressures simultaneously. Experimental tests with nine newborns confirmed that our device is suitable for the measurement of the natural NNS behavior and for the extrapolation of parameters related to the suction/expression rhythmicity. Preliminary results encourage future studies to evaluate the possibility to use these parameters as indicators of oral feeding readiness of premature infants.

  19. Preliminary study on the energy coefficients of buildings; Vorstudie zur Erhebung von Energiekennzahlen von Wohnbauten

    Energy Technology Data Exchange (ETDEWEB)

    Dettli, R.; Bade, S. [Econcept AG, Zuerich (Switzerland); Baumgartner, A.; Bleisch, M. [Amstein und Walthert, Zuerich (Switzerland)

    2007-11-15

    This comprehensive report for the Swiss Federal Office of Energy (SFOE) presents the results of a preliminary study concerning the definition of a method for the cost-effective and reliable collection of data and the calculation of energy coefficients for residential buildings in Switzerland. On the basis of data already collected, typical coefficients for various types of building are proposed. Also, reasons for considerable differences between the data of various Swiss Cantons are investigated. Requirements and criteria for the judgement of the energy coefficients are discussed and the methods used by various Swiss cities and Cantons are reviewed. A comprehensive appendix completes the report.

  20. Incorporation of tramadol drug into Li-fluorohectorite clay: A preliminary study of a medical nanofluid

    Science.gov (United States)

    Valdés, L.; Hernández, D.; de Ménorval, L. Ch.; Pérez, I.; Altshuler, E.; Fossum, J. O.; Rivera, A.

    2016-07-01

    During the last years, clays have been increasingly explored as hosts for drugs. In the present paper, we have been able to host the non-steroidal anti-inflammatory drug, Tramadol, into the clay Li-fluorohectorite (Li-Fh). We preliminary evaluate its incorporation by means of UV spectroscopy and X ray diffraction. Our results indicate that the clay hosts the drug molecule in its interlayer space. We suggest a set of parameters to guarantee an efficient incorporation process. Future studies will concentrate on the release of the drug from the clay nanofluid.

  1. Preliminary studies of the constructive technical viability of a refrigeration using eolica energy

    OpenAIRE

    Jorge de Jesus Passinho e Silva

    2004-01-01

    Resumo: Neste trabalho procuramos analisar o funcionamento de um compressor de freqüência variável que utilizasse a energia eólica, em São Luis do Maranhão, para manter um sistema de refrigeração funcionando. Para isto foi necessário conhecer os valores locais das velocidades de vento e escolhemos o cata vento tipo Savonius para atingirmos nosso objetivo Abstract: Preliminary studies of the constructive e technical viability, of a system of refrigeration using Eolica Energy, in order to ke...

  2. A preliminary and qualitative metallomics study of mercury in the muscle of fish from Amazonas, Brazil.

    Science.gov (United States)

    Moraes, Paula M; Santos, Felipe A; Padilha, Cilene C F; Vieira, José C S; Zara, Luiz F; de M Padilha, Pedro

    2012-12-01

    This paper presents preliminary findings for a metallomics study of mercury in the muscle of the fish species from Amazonas, Brazil, after protein separation by two-dimensional polyacrylamide gel electrophoresis and subsequent evaluation of mercury by synchrotron radiation X-ray fluorescence. The fluorescence spectra revealed mercury in two protein spots. The mercury-containing protein spots showed molecular weights of 20.8 ± 0.7 and 19.8 ± 0.5 kDa and isoelectric points of 5.6 ± 0.2 and 7.5 ± 0.3, respectively.

  3. A preliminary study to find out maximum occlusal bite force in Indian individuals

    DEFF Research Database (Denmark)

    Jain, Veena; Mathur, Vijay Prakash; Pillai, Rajath;

    2014-01-01

    PURPOSE: This preliminary hospital based study was designed to measure the mean maximum bite force (MMBF) in healthy Indian individuals. An attempt was made to correlate MMBF with body mass index (BMI) and some of the anthropometric features. METHODOLOGY: A total of 358 healthy subjects in the age...... in subjects having concave facial profile when compared to convex (P = 0.045) and straight (P = 0.039) facial profile. BMI and arch form showed no significant relationship with MMBF. CONCLUSION: The MMBF is found to be affected by gender and some of the anthropometric features like facial form and palatal...

  4. SPANISH MULTICENTRIC STUDY ABOUT NUTRITION-INFLAMATIONhn WITH MID DILUTION (ENIMID STUDY: PRELIMINARY RESULTS

    Directory of Open Access Journals (Sweden)

    Barril G

    2012-06-01

    CONCLUSIONS: 1-The preliminary results show that MidDilution provides a good removal of small and middle molecules, increases appetite by providing a proper balance of cytokines through stimulation of antiinflamatory ones and neuropeptide Y. 2-It provides an improvement of body composition. Finally MidDilution improves nutritional parameters which leads to a better quality of life, as well as physical and mental status.

  5. Compulsive sexual behavior inventory: a preliminary study of reliability and validity.

    Science.gov (United States)

    Coleman, E; Miner, M; Ohlerking, F; Raymond, N

    2001-01-01

    This preliminary study was designed to develop empirically a scale of compulsive sexual behavior (CSB) and to test its reliability and validity in a sample of individuals with nonparaphilic CSB (N = 15), in a sample of pedophiles (N = 35) in treatment for sexual offending, and in a sample of normal controls (N = 42). Following a factor analysis and a varimax rotation, those items with factor loadings on the rotated factors of greater than .60 were retained. Three factors were identified, which appeared to measure control, abuse, and violence. Cronbach's alphas indicated that the subscales have good reliability. The 28-item scale was then tested for validity by a linear discriminant function analysis. The scale successfully discriminated the nonparaphilic CSB sample and the pedophiles from controls. Further analysis indicated that this scale is a valid measure of CSB in that there were significant differences between the three groups on the control subscale. Pedophiles scored significantly lower than the other two groups on the abuse subscale, with the other two groups not scoring significantly differently from one another. This indicated that pedophiles were more abusive than the nonparaphilic CSB individuals or the controls. Pedophiles scored significantly lower than controls on the violence subscale. Nonparaphilic individuals with compulsive sexual behavior scored slightly lower on the violence subscale, although not significantly different. As a preliminary study, there are several limitations to this study, which should be addressed, in further studies with larger sample sizes.

  6. Preliminary Phytochemical, UV-VIS, HPLC and Anti-bacterial Studies on Gracilaria corticata J. Ag

    Institute of Scientific and Technical Information of China (English)

    Krishnaveni Eahamban; Johnson Marimuthu Antonisamy

    2012-01-01

    Objective: The present study aimed to investigate the preliminary phytochemical analysis and UV-VIS, HPTC profiling and the antibacterial activity of Gracilaria corticata J. Ag extracts against the Gram positive and Gram negative bacteria. Methods: Preliminary phytochemical screening was carried out by Harborne method. The G. corticata extracts were tested against bacteria by the agar disc diffusion method. Results: The results of the presence study showed the presence of alkaloids, steroids, phenolic groups, saponins, tannin, flavonoids, terpenoids, glycosides and sugars. Proteins, xantoproteins, coumarins and catechin did not show any positive result for their presence in any of the six extracts of Gracilaria corticata tested. The result of the present study revealed the various behavior character of Gracilaria corticata crude drug. The UV-VIS spectrum profile of Gracilaria corticata methanolic, petroleum ether, benzene and aqueous extracts profiles were recorded. The HPLC profile of Gracilaria corticata petroleum ether benzene and aqueous extracts were tabulated. The maximum (9/12 bacterial pathogens) degree of antibacterial activity was observed in isopropanol soxhlet extracts followed by isopropanol cold extracts (7/12 bacterial pathogens). Conclusion: The results of the present study showed that G. corticata may be rich sources of phytoconstituents which can be isolated and further screened for different kinds of biological activities, depending on their reported therapeutic uses.

  7. High risk cohort study for psychiatric disorders in childhood: rationale, design, methods and preliminary results.

    Science.gov (United States)

    Salum, Giovanni Abrahão; Gadelha, Ary; Pan, Pedro Mario; Moriyama, Tais Silveira; Graeff-Martins, Ana Soledade; Tamanaha, Ana Carina; Alvarenga, Pedro; Valle Krieger, Fernanda; Fleitlich-Bilyk, Bacy; Jackowski, Andrea; Sato, João Ricardo; Brietzke, Elisa; Polanczyk, Guilherme Vanoni; Brentani, Helena; de Jesus Mari, Jair; Do Rosário, Maria Conceição; Manfro, Gisele Gus; Bressan, Rodrigo Affonseca; Mercadante, Marcos Tomanik; Miguel, Eurípedes Constantino; Rohde, Luis Augusto

    2015-03-01

    The objective of this study is to present the rationale, methods, design and preliminary results from the High Risk Cohort Study for the Development of Childhood Psychiatric Disorders. We describe the sample selection and the components of each phases of the study, its instruments, tasks and procedures. Preliminary results are limited to the baseline phase and encompass: (i) the efficacy of the oversampling procedure used to increase the frequency of both child and family psychopathology; (ii) interrater reliability and (iii) the role of differential participation rate. A total of 9937 children from 57 schools participated in the screening procedures. From those 2512 (random = 958; high risk = 1554) were further evaluated with diagnostic instruments. The prevalence of any child mental disorder in the random strata and high-risk strata was 19.9% and 29.7%. The oversampling procedure was successful in selecting a sample with higher family rates of any mental disorders according to diagnostic instruments. Interrater reliability (kappa) for the main diagnostic instrument range from 0.72 (hyperkinetic disorders) to 0.84 (emotional disorders). The screening instrument was successful in selecting a sub-sample with "high risk" for developing mental disorders. This study may help advance the field of child psychiatry and ultimately provide useful clinical information.

  8. Validation of the RRE-90 Scale to Predict Stroke Risk after Transient Symptoms with Infarction: A Prospective Cohort Study.

    Directory of Open Access Journals (Sweden)

    Bo Song

    Full Text Available The risk of stroke after a transient ischemic attack (TIA for patients with a positive diffusion-weighted image (DWI, i.e., transient symptoms with infarction (TSI, is much higher than for those with a negative DWI. The aim of this study was to validate the predictive value of a web-based recurrence risk estimator (RRE; http://www.nmr.mgh.harvard.edu/RRE/ of TSI.Data from the prospective hospital-based TIA database of the First Affiliated Hospital of Zhengzhou University were analyzed. The RRE and ABCD2 scores were calculated within 7 days of symptom onset. The predictive outcome was ischemic stroke occurrence at 90 days. The receiver-operating characteristics curves were plotted, and the predictive value of the two models was assessed by computing the C statistics.A total of 221 eligible patients were prospectively enrolled, of whom 46 (20.81% experienced a stroke within 90 days. The 90-day stroke risk in high-risk TSI patients (RRE ≥4 was 3.406-fold greater than in those at low risk (P <0.001. The C statistic of RRE (0.681; 95% confidence interval [CI], 0.592-0.771 was statistically higher than that of ABCD2 score (0.546; 95% CI, 0.454-0.638; Z = 2.115; P = 0.0344 at 90 days.The RRE score had a higher predictive value than the ABCD2 score for assessing the 90-day risk of stroke after TSI.

  9. Internal electric field profile in thin film hydrogenated amorphous silicon diodes studied by the transient-null-current method

    Energy Technology Data Exchange (ETDEWEB)

    Han, D.; Yeh, C.; Wang, K.; Wang, Q.

    1997-07-01

    The authors demonstrate that the internal field of a thin a-Si:H pin solar cells can be measured using the transient-null-current method. This method was previously developed to measure the internal field profile in a-Si alloy Schottky barrier. The internal electric field profile was determined by measuring the forward-bias voltages that tune the transient photocurrents generated by a pulsed laser at various wavelengths to zero. They adopt the same technique to a-Si:H p-i-n solar cells. In the case of p-i-n structure, they need to consider both space charge contributed by photogenerated carriers and carrier recombination which disturb the internal field. They use two critical conditions to minimize these effects. (1) To limit the contribution of photocarriers to space-charge distribution, the total charge collected is less than 10{sup {minus}10} C per pulse, and a repetition rate 1 Hz is used to ensure that the diode remains close to its equilibrium state, (2) The measuring time window is about 1--6 {micro}s following the displacement current. Typically the RC constant of diode is <1 {micro}s and the rise time of the forward-bias recombination current is 6.0 x {micro}s. They apply the signal average to process the forward-bias voltage. The error is within {+-}0.05 V. With this technique they can study the effect of variety of structure design or processing on the device performance.

  10. Study of transient rod extraction failure without RBM in a BWR; Estudio del transitorio error de extraccion de barra sin RBM en un BWR

    Energy Technology Data Exchange (ETDEWEB)

    Vallejo Q, J. A.; Martin del Campo M, C.; Fuentes M, L.; Francois L, J. L., E-mail: amhed_jvq@hotmail.com [UNAM, Facultad de Ingenieria, Departamento de Sistemas Energeticos, Ciudad Universitaria, 04510 Ciudad de Mexico (Mexico)

    2015-09-15

    The study and analysis of the operational transients are important for predicting the behavior of a system to short-term events and the impact that would cause this transient. For the nuclear industry these studies are indispensable due to economic, environmental and social impacts that could cause an accident during the operation of a nuclear reactor. In this paper the preparation, simulation and analysis results of the transient rod extraction failure in which not taken into operation the RBM is presented. The study was conducted for a BWR of 2027 MWt, in an intermediate cycle of its useful life and using the computer code Simulate-3K a scenario of anomalies was created in the core reactivity which gave a coherent prediction to the type of presented event. (Author)

  11. Transient global amnesia mimics: Transient epileptic amnesia

    Directory of Open Access Journals (Sweden)

    Nicolas Nicastro

    2014-01-01

    Full Text Available We describe the case of a 79-year-old patient referred for suspected transient global amnesia, after an episode of anterograde amnesia which lasted 90 min. An EEG, performed after the episode, showed bilateral temporal electrographic seizures, orienting the diagnosis toward a transient epileptic amnesia. Transient epileptic amnesia is defined by temporal lobe epilepsy characterized by recurrent transient amnestic episodes of 30–90 min in duration, sometimes associated with olfactory hallucinations or oral automatisms. Response to antiepileptic drugs is excellent. We would like to raise awareness toward this epileptic amnesia when facing atypical or recurrent transient amnestic episodes.

  12. Evaluation of CT virtual intravascular endoscopy in fenestrated stent grafts: a preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Z. [Dept. of Imaging and Applied Physics, Curtin Univ. of Tech., Perth, WA (Australia); Allen, Y.; Fitzsimmons, B.; Hartely, D. [Cook R and D, WA (Australia); Lawrence-Brown, M. [Dept. of Public Health, Curtin Univ. of Tech., Perth, WA (Australia)

    2007-06-15

    We aim in this study to investigate the potential value of CT virtual intravascular endoscopy in patients diagnosed with abdominal aortic aneurysms undergoing fenestrated stent grafts. Both pre-and post-fenestration (within 3 months of implantation) multislice CT data were collected in eight patients and used for generation of virtual endoscopy images in our preliminary study. Variable fenestrations were deployed in 25 aortic branches with scallop fenestration implanted in six aortic ostia, large fenestration in four aortic ostia and small fenestration in 15 renal ostia, respectively. Measurements of the aortic ostia diameters both pre- and post-fenestration were successfully performed with virtual intravascular endoscopy visualization, and endovascular stents as well as their relationship to the aortic ostia were clearly demonstrated. Our results showed that there was no significant change of diameter of the aortic ostia following fenestrated stem grafts. Endovascular stents were clearly visualized on virtual endoscopy images, and no apparent deformity or malrotation was observed in this small group. Our preliminary study provides new insights into anatomic configuration/dimension of aortic ostia and endovascular stents, and virtual intravascular endoscopy could be a valuable technique to follow-up patients treated with fenestrated stent grafts. (orig.)

  13. Preliminary phytochemical, acute oral toxicity and antihepatotoxic study of roots of Paeonia officinalis Linn

    Institute of Scientific and Technical Information of China (English)

    Feroz Ahmad; Nahida Tabassum

    2013-01-01

    Objective: To carry out a preliminary phytochemical, acute oral toxicity and antihepatotoxic study of the roots of Paeonia officinalis (P. officinalis) L. Methods: Preliminary phytochemical investigation was done as per standard procedures. Acute oral toxicity study was conducted as per OECD 425 guidelines. The antihepatotoxic activity of aqueous extract of root of P. officinalis was evaluated against carbon tetrachloride (CCl4) induced hepatic damage in rats. Aqueous extract of P. officinalis at the dose levels of 100 and 200 mg/kg body weight was administered daily for 14 d in experimental animals. Liver injury was induced chemically, by CCl4 administration (1 mL/kg i.p.). The hepatoprotective activity was assessed using various biochemical parameters like aspartate aminotransferase (AST), alanine aminotransferase (ALT), serum alkaline phosphatase (SALP), total bilirubin and total protein (TP) along with histopathological studies. Result: Phytochemical screening revealed that the roots ofP. officinalis contain alkaloids, tannins, saponins, glycosides, carbohydrates, flavonoids, terpenes, steroids and proteins. The aqueous extract did not cause any mortality up to 2000 mg/kg. In rats that had received the root extract at the dose of 100 and 200 mg/kg, the substantially elevated AST, ALT, SALP, total bilirubin levels were significantly lowered, respectively, in a dose dependent manner, along with CCl4 while TP levels were elevated in these groups. Histopathology revealed regeneration of the livers in extract treated groups while Silymarin treated rats were almost normal. Conclusions: The aqueous extract of P. officinalis is safe and possesses antihepatotoxic potential.

  14. Predicting methylphenidate response in attention deficit hyperactivity disorder: a preliminary study.

    Science.gov (United States)

    Johnston, Blair A; Coghill, David; Matthews, Keith; Steele, J Douglas

    2015-01-01

    Methylphenidate (MPH) is established as the main pharmacological treatment for patients with attention deficit hyperactivity disorder (ADHD). Whilst MPH is generally a highly effective treatment, not all patients respond, and some experience adverse reactions. Currently, there is no reliable method to predict how patients will respond, other than by exposure to a trial of medication. In this preliminary study, we sought to investigate whether an accurate predictor of clinical response to methylphenidate could be developed for individual patients, using sociodemographic, clinical and neuropsychological measures. Of the 43 boys with ADHD included in this proof-of-concept study, 30 were classed as responders and 13 as non-responders to MPH, with no significant differences in age nor verbal intelligence quotient (IQ) between the groups. Here we report the application of a multivariate analysis approach to the prediction of clinical response to MPH, which achieved an accuracy of 77% (p = 0.005). The most important variables to the classifier were performance on a 'go/no go' task and comorbid conduct disorder. This preliminary study suggested that further investigation is merited. Achieving a highly significant accuracy of 77% for the prediction of MPH response is an encouraging step towards finding a reliable and clinically useful method that could minimise the number of children needlessly being exposed to MPH. © The Author(s) 2014.

  15. Raman spectroscopy and SERS analysis of ovarian tumour derived exosomes (TEXs): a preliminary study

    Science.gov (United States)

    Kerr, Laura T.; Gubbins, Luke; Weiner Gorzel, Karolina; Sharma, Shiva; Kell, Malcolm; McCann, Amanda; Hennelly, Bryan M.

    2014-05-01

    Here we report a preliminary study based on the application of Raman spectroscopy and surface enhanced Raman spectroscopy (SERS) to investigate the compositional differences between exosomes derived from ovarian carcinoma cells (cell line A2780) grown in normoxia (normal O2 conditions) and hypoxia (1% O2 conditions). Exosomes are integral to cell signalling, and are of interest in the study of how cells communicate within their environment. We are particularly interested in identifying whether hypoxia induced senescent cells can communi- cate via exosomes with neighbouring tumour cells, thereby causing them to become senescent and therefore radio and chemo resistant. With this goal in mind, we performed a preliminary study on the application of Raman spectroscopy and SERS to analyse the biomolecular fingerprint of both groups of exosomes and to investigate whether there exists a different biomolecular composition associated with exosomes derived from hypoxic cells in comparison to those from normoxic cells. We also applied multivariate statistical techniques for the classification of both groups of exosomes.

  16. Preliminary phytochemical and antimicrobial studies on a spike-moss Selaginella inaequalifolia (hook. & grev.) Spring

    Institute of Scientific and Technical Information of China (English)

    Varaprasadham Irudayaraj; Janaky M; Marimuthu Johnson; Nallayan Selvan

    2010-01-01

    Objective: To screen the anti-cancer spike-mosses for the presence of various bioactivities and to identify the important bioactive chemicals present in Selaginella inaequalifolia (S.inaequalifolia ) (Hook. & Grev.) Spring. Methods: Preliminary phytochemical screening was done by following the method of Brindha et al. Antimicrobial study was carried out by disc diffusion method. Results: Results of preliminary phytochemical screening on five different extracts (petroleum ether, benzene, chloroform, ethanol and distilled water) of the spike-mossS. inaequalifolia show the presence steroids, triterpenes, phenolic group, tannin, sugars and catechin. Alkaloids, amino acids, anthraquinone and reducing sugar did not show any positive result. Among the five different extracts, ethanol and chloroform extracts show the presence of maximum number (4 each) of compounds. The results on antimicrobial studies show that all the three microbes [Staphylococcus aureus (S. aureus), Escherichia coli (E. coli) and Candida albicans(C. albicans) ] tested are resistant to the ethanol extract and susceptible to petroleum ether extract. The petroleum ether extract shows maximum inhibition with 45 mm of inhibition zone in C. albicans. The inhibition zone in S. aureus and E. coli are 26 mm and 22 mm respectively. Conclusions: The present study shows S. inaequalifolia having potent antibacterial and anticandidal activities.

  17. EVALUATION OF PHYSICOCHEMICAL AND PRELIMINARY PHYTOCHEMICAL STUDIES ON THE ROOT OF BOMBAX CEIBA LINN.

    Directory of Open Access Journals (Sweden)

    Garg Nitika

    2011-03-01

    Full Text Available The present communication attempts to evaluate the physicochemical and preliminary phytochemical studies on the roots of Bombax ceiba Linn. or the silk cotton tree. This tropical tree has a straight tall trunk and its leaves are deciduous in winter. Red flower with 5 petals appear in the spring before the new foliage. The whole plant of Bombax ceiba used as traditional folk medicines for the treatment of antidysenteric, antidiahorreal and antipyretic effects. Bombax ceiba Linn. Contains glycosides, tannins, flavanoid, b-sitosterol and lupeol. The present study deals with phytochemical investigations of Bombax ceiba root including determination of loss on drying, ash values, TLC and extractive values. The preliminary phytochemical screening of powdered drug was also carried out. The qualitative chemical examinations revealed the presence of various phytoconstituents like flavanoid, terpenoid saponins, phenolic compounds and mucilage’s in the extracts. The study revealed specific identities for the particular crude drug which will be useful in identification and control to adulterations of the raw drug.

  18. Clinical and neuroimaging correlates of antiphospholipid antibodies in multiple sclerosis: a preliminary study

    Directory of Open Access Journals (Sweden)

    Gonzalez-Toledo Eduardo

    2007-10-01

    Full Text Available Abstract Background The presence of antiphospholipid antibodies (APLA in multiple sclerosis (MS patients has been reported frequently but no clear relationship between APLA and the clinical and neuroimaging features of MS have heretofore been shown. We assessed the clinical and neuroimaging features of MS patients with plasma APLA. Methods A consecutive cohort of 24 subjects with relapsing-remitting (RR MS were studied of whom 7 were in remission (Rem and 17 in exacerbation (Exc. All subjects were examined and underwent MRI of brain. Patients' plasma was tested by standard ELISA for the presence of both IgM and IgG antibodies using a panel of 6 targets: cardiolipin (CL, β2 glycoprotein I (β2GPI, Factor VII/VIIa (FVIIa, phosphatidylcholine (PC, phosphatidylserine (PS and phosphatidylethanolamine (PE. Results In exacerbation up to 80% of MS subjects had elevated titers of IgM antibodies directed against the above antigens. However, in remission, less than half of MS patients had elevated titers of IgM antibodies against one or more of the above antigens. This difference was significant, p Conclusion The findings of this preliminary study show that increased APLA IgM is associated with exacerbations of MS. Currently, the significance of this association in pathogenesis of MS remains unknown. However, systematic longitudinal studies to measure APLA in larger cohorts of patients with relapsing-remitting MS, particularly before and after treatment with immunomodulatory agents, are needed to confirm these preliminary findings.

  19. Physical and Dosimetric Optimization of Laser Equipment in Dermatology: A Preliminary Study

    Directory of Open Access Journals (Sweden)

    A. Soriani

    2014-01-01

    Full Text Available The aim of this preliminary study is to investigate the correlation between clinical set-up at present used in the treatment of specific skin conditions and laser beam absorbed power in the tissue. This study focused on the CO2 and Nd-Yag laser equipment used in the daily clinical practice in the Department of Dermatology of San Gallicano Institute in Rome. Different types of tissue-equivalent material with various water and haemoglobin concentrations were tested to evaluate laser beam attenuation power. In particular, thinly sliced pork loin, of uniform consistency and without fat, was selected for its high content of haemoglobin to mimic human tissues. An optical power meter was used to measure the power or energy of a laser beam. During measurements, the tissue equivalent phantoms were positioned on the detector head and the laser beam was orthogonally oriented. The results of two experimental set-ups are reported here. The dependence of residual power (W as a function of ex vivo tissue thickness (mm for different laser output powers was studied. Data were fitted by a parametric logistic equation. These preliminary data allow for more accurately determining the energy fraction released from lasers to the tissues in order to improve clinical outcomes.

  20. Preliminary Study on the High Efficiency Supercritical Pressure Water-Cooled Reactor for Electricity Generation

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Yoon Yeong; Park, Jong Kyun; Cho, Bong Hyun and others

    2006-01-15

    This research has been performed to introduce a concept of supercritical pressure water cooled reactor(SCWR) in Korea The area of research includes core conceptual design, evaluation of candidate fuel, fluid systems conceptual design with mechanical consideration, preparation of safety analysis code, and construction of supercritical pressure heat transfer test facility, SPHINX, and preliminary test. As a result of the research, a set of tools for the reactor core design has been developed and the conceptual core design with solid moderator was proposed. The direct thermodynamic cycle has been studied to find a optimum design. The safety analysis code has also been adapted to supercritical pressure condition. A supercritical pressure CO2 heat transfer test facility has been constructed and preliminary test proved the facility works as expected. The result of this project will be good basis for the participation in the international collaboration under GIF GEN-IV program and next 5-year mid and long term nuclear research program of MOST. The heat transfer test loop, SPHINX, completed as a result of this project may be used for the power cycle study as well as further heat transfer study for the various geometries.