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Sample records for charge study children

  1. Physical Education and Children with CHARGE Syndrome: Research to Practice

    Science.gov (United States)

    Lieberman, Lauren J.; Haibach, Pamela; Schedlin, Haley

    2012-01-01

    Introduction: Children with CHARGE syndrome often experience significantly delayed motor development, which affects their performance in many motor skills and physical activities. The purpose of this study was to determine the status of physical education provided to children with CHARGE syndrome. There were five main areas of focus: (1) physical…

  2. Development and characteristics of children with Usher and CHARGE syndrome

    DEFF Research Database (Denmark)

    Dammeyer, Jesper Herup

    2012-01-01

    OBJECTIVE: Individuals with Usher syndrome or CHARGE syndrome are faced with a number of difficulties concerning hearing, vision, balance, and language development. The aim of the study is to describe the developmental characteristics of children with Usher syndrome and CHARGE syndrome......, respectively. METHOD: Data about the developmental characteristics of 26 children with Usher syndrome and 17 children with CHARGE syndrome was obtained. Associations between deafblindness (dual sensory loss), motor development (age of walking), language abilities, and intellectual outcome of these children...... were explored for each group independently. RESULTS: Both groups of children face a number of difficulties associated with vision, hearing, language, balance and intellectual outcome. Intellectual disability and/or language delay was found among 42% of the children with Usher syndrome and among 82% of...

  3. Cochlear implantation in children with "CHARGE syndrome": surgical options and outcomes.

    Science.gov (United States)

    Ricci, Giampietro; Trabalzini, Franco; Faralli, Mario; D'Ascanio, Luca; Cristi, Cristina; Molini, Egisto

    2014-03-01

    CHARGE syndrome is a rare, polymalformative disease, representing one of the major causes of associated blindness and deafness. Bilateral, severe-profound, sensorineural hearing loss is common in CHARGE children. Aim of this study is to present our results in children with "CHARGE syndrome" submitted to cochlear implantation (CI). The frequency of anatomic anomalies, possible variations in the surgical technique of CI, and the audiological/rehabilitative benefits attained in our patients are reported. we submitted 5 children affected by CHARGE syndrome with profound, bilateral, sensorineural hearing loss to CI. Otoacoustic emissions, auditory brainstem response, acoustic impedance testing, cranial computed tomography and magnetic resonance were carried out preoperatively in all children. CI was performed using the mastoidotomy-posterior tympanotomy approach in two cases, and the suprameatal approach in three children. Infant toddler-meaningful auditory integration scale was used to evaluate kid's audiological performance before and after CI. Intra-operatory findings and postsurgical complications were evaluated. Among our patients, intraoperative anatomical malformations were cochlear hypoplasia (100 %), ossicles malformations (100 %), semicircular canals aplasia (100 %), oval window atresia (60 %), round window atresia (40 %), widening of the aqueduct of the vestibule (20 %), and aberrant course of the facial nerve (20 %). No intra- or postoperative complication was recorded in relation to implant positioning. After a follow-up ranging from 1 to 4.5 years, only 2/5 patients used oral language as the sole mean of communication, 1 started utilizing oral language as the main mean of communication, while 2 patients did not develop any linguistic ability. In conclusion, CI in patients with CHARGE association is feasible and, despite results variability, it should be carried out in CHARGE children with severe hearing loss as soon as possible. Although the selection of a

  4. Who's in charge of children's environmental health at school?

    Science.gov (United States)

    Paulson, Jerome; Barnett, Claire

    2010-01-01

    Children spend many hours each week in and around school buildings. Their short- and long-term health outcomes and ability to learn are affected by numerous environmental factors related to the school buildings, the school grounds, the school transportation system, and the use of various products and materials in and around the school. Many school buildings are old, and they-and even newer buildings-can contain multiple environmental health hazards. While some districts self-report they have environmental health policies in place, no independent verification of these policies or their quality exists. Teachers and other staff, but not children who are more vulnerable to hazards than adults, are afforded some protections from hazards by Occupational Safety and Health Administration (OSHA) regulations, by their employment contracts, or through adult occupational health services. Major environmental problems include: indoor air quality, lighting, pests and pesticides, heavy metals and chemical management issues, renovation of occupied buildings, noise, and cleaning processes and products. No agency at the federal or state levels is charged with ensuring children's health and safety in and around school buildings. No systematic means exists for collecting data about exposures which occur in the school setting. Recommendations are made for dealing with issues of data collection, federal actions, state and local actions, and for building the capacity of the Environmental Protection Agency and the Centers for Disease Control and Prevention-designated and funded Pediatric Environmental Health Specialty Units (PEHSU) in responding to and evaluating risks to children's environmental health in schools. PMID:20359989

  5. Experimental study of rare charged pion decays

    CERN Document Server

    Pocanic, Dinko; van der Schaaf, Andries

    2014-01-01

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

  6. Cochlear Implants in Children Diagnosed with CHARGE Syndrome

    Directory of Open Access Journals (Sweden)

    Cardoso, Carolina Costa

    2013-09-01

    Full Text Available Introduction: The CHARGE association (coloboma of the eyes; heart disease; atresia of the choanae; retarded growth and development; genital hypoplasia/genitourinary anomalies; ear anomalies and/or hearing loss was first described in 1979 by Hall, and among its main features is hearing loss. This study presents a case aiming to establish relationships between performance on Infant Toddler Meaningful Auditory Integration Scale (IT-MAIS and Meaningful Use of Speech Scales (MUSS tests and the analysis of hearing and language categories of a patient diagnosed with CHARGE syndrome, before and after cochlear implant (CI surgery. Case Report: A 7-year-old girl was diagnosed with CHARGE. She had severe sensorineural hearing loss and was a prelingual unilateral CI user. We analyzed data from the patient's medical records regarding therapies and video recordings. Results: The patient showed positive results in all evaluations after CI. IT-MAIS rose from 5 to 90% following the use of CI. MUSS also rose, from 75 to 72.5%, after use of CI. Classification of Auditory Skills changed from category 1 before use of CI to category 6 after use of CI. Classification of Language Skills changed from category 1 before use of CI to category 3 after use of CI. The CI is an aid but there are many factors in the therapeutic process, and great heterogeneity in individuals diagnosed with CHARGE should be investigated. Conclusion: The development of listening and language skills after CI use was demonstrated by IT-MAIS and MUSS tests, and categorization of speech and hearing in this child with a diagnosis of CHARGE syndrome shows that CI can be an effective technological resource to provide information on hearing as one source for language construction.

  7. Experimental study of diffusion charging of aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Pui, D.Y.H.

    1976-03-01

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

  8. Studying Charged Particle Optics: An Undergraduate Course

    Science.gov (United States)

    Ovalle, V.; Otomar, D. R.; Pereira, J. M.; Ferreira, N.; Pinho, R. R.; Santos A. C. F.

    2008-01-01

    This paper describes some computer-based activities to bring the study of charged particle optics to undergraduate students, to be performed as a part of a one-semester accelerator-based experimental course. The computational simulations were carried out using the commercially available SIMION program. The performance parameters, such as the focal…

  9. Studies in children.

    Science.gov (United States)

    Perera, Frederica P; Edwards, Susan C

    2011-01-01

    This chapter first discusses the urgent need for prevention of childhood diseases that impose a huge and growing burden on families and society. It provides a review of recent research in this area to illustrate both the strengths and limitations of molecular epidemiology in drawing needed links between environmental exposures and illness in children. For illustration, three of the major diseases in children are discussed: asthma, cancer and developmental disorders. All three impose significant difficulties, have increased in recent decades, and are thought to be caused in substantial part by environmental factors, such as toxic exposures due to lifestyle choices (i.e. smoking and diet), pollutants in the workplace, ambient air, water and the food supply. These exogenous exposures can interact with "host" factors, such as genetic susceptibility and nutritional deficits, to cause disease. Molecular epidemiology has provided valuable new insights into the magnitude and diversity of exposures beginning in utero, the unique susceptibility of the young, and the adverse preclinical and clinical effects resulting from the interactions between these factors. However, molecular epidemiology also faces certain constraints and challenges that are specific to studies of the very young, including ethical issues, technical issues due to the limited amount of biological specimens that can be obtained, and communication of results to parents and communities. These challenges are particularly apparent when incorporating the newer epigenetic and "omic" techniques and biomarkers into studies of children's diseases. PMID:22997878

  10. Children and Clinical Studies: Why Clinical Studies Are Important

    Medline Plus

    Full Text Available ... Children & Clinical Studies NHLBI Trials Clinical Trial Websites Children and Clinical Studies Learn more about Children and Clinical Studies Importance of Children in Clinical Studies Children have often had to ...

  11. Charge coupled device image sensor study

    Science.gov (United States)

    1974-01-01

    An evaluation of a charge-coupled device (CCD) image sensors for use in spacecraft-borne imaging systems was conducted. The study resulted in design recommendations for two sensors, an approximately 500 times 500 element imaging device and a 1 times 190 element linear imaging device with a 190 times 121 buffer store. Emphasis was placed on the higher resolution, area-imaging sensor. The objectives of the proposed sensors are listed, results of the experiments are analyzed, and estimates of the device performance are presented. A summary of the major technical recommendations is included.

  12. Row charge cratering calculations. [Feasibility studies

    Energy Technology Data Exchange (ETDEWEB)

    Miller, L.W.; Matuska, W.

    1978-06-01

    Two-dimensional calculations have been done to determine the feasibility of constructing deep canals with nuclear explosives subject to the limitation in the proposed PNE Treaty. The conditions under which a series of explosives set in a row can be approximated by a cylindrical line source have been determined. Using this result, the possibility of lifting 250 m of overburden with 150-kt charges spaced at 50-m intervals has been investigated. This study shows that for a variety of equations of state for the geological medium, there appears little possibility that such an excavation can be accomplished.

  13. Solar Array and Auroral Charging Studies of DMSP Spacecraft

    Science.gov (United States)

    Matias, Kelwin

    2013-01-01

    The SSJ electrostatic analyzers and the SSIES plasma instruments on the DMSP spacecraft in low Earth polar orbit can be used to conduct case studies of auroral and solar array charging. We will use a program written in the Interactive Data Language (IDL) to evaluate questionable charging events in the SSJ records by comparing charging signatures in SSJ and SSIES data. In addition, we will assemble a number of case studies of solar array charging showing the signatures from the SSJ data and compare to the SSIES charging signatures. In addition we will use Satellite Tool Kit (STK) to propagate orbits, obtain solar intensity, and use to verify onset of charging with sunrise.

  14. A charge collection study with dedicated RD50 charge multiplication sensors

    International Nuclear Information System (INIS)

    This study investigates the charge collection efficiency of silicon strip detectors, produced by MICRON Semiconductor Co., Ltd. within the CERN RD50 collaboration, designed specifically to understand the effect of design parameters on the onset and magnitude of charge multiplication. Charge collection measurements are performed before and after irradiation with a proton fluence of 1×1015 1 MeV neq/cm2 (neq/cm2) and neutron fluence ranging from 1–5×1015 neq/cm2. Structures on these devices include varying diffusion times and energies for the implantation process, different sensor thicknesses, the use of intermediate biased or floating strips between the readout strips, and several different strip width and pitch geometries. The charge collection for these devices is studied as a function of the bias voltage, looking for indications of charge multiplication. Results are compared to standard float zone 300μm thick silicon strip sensors having a strip width of 25μm and pitch of 80μm. -- Highlights: •Specially designed silicon detectors were developed to investigate charge multiplication. •Charge collection measurements were performed before and after irradiation. •Charge multiplication only seen ≥5×1015neq/cm2. •Decreasing width/pitch increases collected charge. •Increasing implant energy/diffusion time increased collected charge

  15. Children and Clinical Studies: Why Clinical Studies Are Important

    Medline Plus

    Full Text Available ... NHLBI Trials Clinical Trial Websites Children and Clinical Studies Learn more about Children and Clinical Studies Importance of Children in Clinical Studies Children have often had to accept medicines and ...

  16. "In Charge of the Truffula Seeds": On Children's Literature, Rationality and Children's Voices in Philosophy

    Science.gov (United States)

    Johansson, Viktor

    2011-01-01

    In this paper I investigate how philosophy can speak for children and how children can have a voice in philosophy and speak for philosophy. I argue that we should understand children as responsible rational individuals who are involved in their own philosophical inquiries and who can be involved in our own philosophical investigations--not because…

  17. Flash X Ray: A Diagnostic Tool for Shaped Charge Studies

    Directory of Open Access Journals (Sweden)

    S. G. Tatake

    1992-10-01

    Full Text Available At present many antitank weapon systems are employing shaped charge warheads. It is, therefore, extremely important for a designer to avail of the methods capable of predicting performance of shaped charges, mainly to achieve maximum penetration. For this purpose, it is necessary to study the behaviour of the shaped charge during actual firing tests. These tests are difficult because of high speed of events that take place, production of intense light, smoke, debris, etc, and the large scale destruction caused. To overcome these difficulties, flash x-ray system during the jet studies on 30, 60 and 90 mm shaped charges and the evaluation of jet characteristics parameters.

  18. A study of SCATHA eclipse charging

    Science.gov (United States)

    Li, Wei-Wei; Whipple, Elden C.

    1988-01-01

    The events of charging of the SCATHA satellite in eclipse were investigated and correlated to the spacecraft surface-averaged and angle-averaged fluxes. It is shown that the large negative vehicle potentials produced in eclipse correlated with the net current due to the high-energy plasma electrons. These potentials also depend on the ion energy, ion current, and the average ion yield. An explanation for this behavior is proposed.

  19. Children and Clinical Studies: Why Clinical Studies Are Important

    Medline Plus

    Full Text Available ... E-Newsletters About NHLBI Organization NHLBI Director Budget, Planning, & Legislative Advisory ... Learn more about Children and Clinical Studies Importance of Children in Clinical Studies Children have often ...

  20. Study of the Electric Charge Carried by Aerosols

    International Nuclear Information System (INIS)

    To study the contribution of electrical forces to filtration phenomena, and to calibrate electrostatic aerosol precipitators, the authors investigated the charge state and studied neutralization and charge by diffusion of the particles of varying diameters which are used as test aerosols. The aerosol used consisted of pulverized monodispersed spheres of latex. The method by which these particles are produced is first described. Monodispersion of the aerosol is checked by an aerosol spectrometer and by electron microscopy. Parasite particles resulting either from residual impurities in the double-distilled water or from the dispersant present in the suspension are retained by a diffusion filter. The electric charge carried by these particles in the conditions of production and use reported was determined by two different diameters: 0.365 μm mean charge: 8 elementary charges; 0.557 μm mean charge 10 elementary charges. The percentage of neutral particles is from 6 to 7%, and practically no particles carrying more than 25 charges have been found. Neutralization by bipolar ions was then studied. The results obtained show good agreement with Boltzmann's law. (author)

  1. Electrostatic interaction between nonuniformly charged colloids: experimental and numerical study.

    Science.gov (United States)

    Derot, Claire; Porcar, Lionel; Lee, YongJin; Pincus, Phillip A; Jho, YongSeok; In, Martin

    2015-02-10

    The influence of the surface charge distribution on the interaction between nanosized particles in water is reported. The distribution of charges at the surface of initially neutral microemulsion droplets has been modulated by additions of various oligomeric cationic surfactants. The osmotic compressibility of the doped microemulsions was measured by light and small-angle neutrons scattering and reveals that the overall effective interaction induced by the ionic groups is repulsive. However, particular charge distributions decrease the osmotic compressibility much less than others. Independent measurements of the activity of the bromide counterions with specific electrodes evidence a significant decrease in the effective charge, which, however, cannot account for the osmotic compressibility in the framework of the primitive model. The q dependence of the structure factor reveals an attractive contribution over a short distance. Numerical studies assign this attractive contribution to the overlap of hydration shells that are extended as a result of the charge localization. PMID:25587999

  2. Children and Clinical Studies: Why Clinical Studies Are Important

    Medline Plus

    Full Text Available ... Clinical Studies Children have often had to accept medicines and treatments based on what is known to ... children's health with the goal to develop treatments, drugs, and devices specific to children. Resources for a ...

  3. Study of Emergency Power Based on Solar Battery Charging

    OpenAIRE

    Wang Lei; Zhu Mengfu; Chen Ping; Deng Cheng; Liu Zhimeng; Wang Yanan

    2016-01-01

    To study an emergency power based on solar battery charging. Based on the electric-generation principle of solar panel, solar energy is changed into electrical energy. Through voltage conversion circuit and filter circuit, electrical energy is stored in the energy storage battery. The emergency power realizes the conversion from solar energy to electrical energy. The battery control unit has the function of PWM (Pulse-Width Modulation) charging, overcharging protection, over-discharging prote...

  4. Experimental study of charging kinetics in Yttria Stabilized Zirconia

    Energy Technology Data Exchange (ETDEWEB)

    Boughariou, A., E-mail: aicha_boughariou@yahoo.fr [LaMaCoP, Université de Sfax pour le sud, Faculté des Sciences, C.P. 3038 Sfax (Tunisia); Kallel, A. [LaMaCoP, Université de Sfax pour le sud, Faculté des Sciences, C.P. 3038 Sfax (Tunisia); Blaise, G. [LPS. Université Paris-Sud XI, Batiment 510, Orsay 91405 (France)

    2014-06-01

    It is well known that the presence of space charge in an insulator is correlated with an electric breakdown. Many studies have been carried out on the experimental characterization of space charges. In our previous work, we have studied the difference in the charging kinetics between “trapper” insulator (pure spinel) and “conductive” one (Yttria Stabilized Zirconia (YSZ)) at low current density J{sub 0} of primary beam. This difference is attributed to the difference in conductivities. The main objective of this paper is to first review the charging effects occurring when a “conductive” material YSZ is subjected to electron irradiation at low J{sub 0}, using a Scanning Electron Microscopy (SEM), and next to study the dependence of the charge-trapping phenomena in YSZ on the current density. The results show the existence of permanent current in the conductive material which is characterized by a steady state yield σ{sub ∞} which fixes the maximum value of J{sub 0} being withstood by a “conductive” material without charge accumulation beneath its surface.

  5. Solar Wind Charge Exchange Studies Of Highly Charged Ions On Atomic Hydrogen

    International Nuclear Information System (INIS)

    Accurate studies of low-energy charge exchange (CX) are critical to understanding underlying soft X-ray radiation processes in the interaction of highly charged ions from the solar wind with the neutral atoms and molecules in the heliosphere, cometary comas, planetary atmospheres, interstellar winds, etc.. Particularly important are the CX cross sections for bare, H-like, and He-like ions of C, N, O and Ne, which are the dominant charge states for these heavier elements in the solar wind. Absolute total cross sections for single electron capture by H-like ions of C, N, O and fully-stripped O ions from atomic hydrogen have been measured in an expanded range of relative collision energies (5 eV/u-20 keV/u) and compared to previous H-oven measurements. The present measurements are performed using a merged-beams technique with intense highly charged ion beams extracted from a 14.5 GHz ECR ion source installed on a high voltage platform at the Oak Ridge National Laboratory. For the collision energy range of 0.3 keV/u-3.3 keV/u, which corresponds to typical ion velocities in the solar wind, the new measurements are in good agreement with previous H-oven measurements. The experimental results are discussed in detail and compared with theoretical calculations where available.

  6. Computer simulation study of water using a fluctuating charge model

    Indian Academy of Sciences (India)

    M Krishnan; A Verma; S Balasubramanian

    2001-10-01

    Hydrogen bonding in small water clusters is studied through computer simulation methods using a sophisticated, empirical model of interaction developed by Rick et al (S W Rick, S J Stuart and B J Berne 1994 J. Chem. Phys. 101 6141) and others. The model allows for the charges on the interacting sites to fluctuate as a function of time, depending on their local environment. The charge flow is driven by the difference in the electronegativity of the atoms within the water molecule, thus effectively mimicking the effects of polarization of the charge density. The potential model is thus transferable across all phases of water. Using this model, we have obtained the minimum energy structures of water clusters up to a size of ten. The cluster structures agree well with experimental data. In addition, we are able to distinctly identify the hydrogens that form hydrogen bonds based on their charges alone, a feature that is not possible in simulations using fixed charge models. We have also studied the structure of liquid water at ambient conditions using this fluctuating charge model.

  7. Charge collection studies in irradiated HV-CMOS particle detectors

    Science.gov (United States)

    Affolder, A.; Andelković, M.; Arndt, K.; Bates, R.; Blue, A.; Bortoletto, D.; Buttar, C.; Caragiulo, P.; Cindro, V.; Das, D.; Dopke, J.; Dragone, A.; Ehrler, F.; Fadeyev, V.; Galloway, Z.; Gorišek, A.; Grabas, H.; Gregor, I. M.; Grenier, P.; Grillo, A.; Hommels, L. B. A.; Huffman, T.; John, J.; Kanisauskas, K.; Kenney, C.; Kramberger, G.; Liang, Z.; Mandić, I.; Maneuski, D.; McMahon, S.; Mikuž, M.; Muenstermann, D.; Nickerson, R.; Perić, I.; Phillips, P.; Plackett, R.; Rubbo, F.; Segal, J.; Seiden, A.; Shipsey, I.; Song, W.; Stanitzki, M.; Su, D.; Tamma, C.; Turchetta, R.; Vigani, L.; Volk, J.; Wang, R.; Warren, M.; Wilson, F.; Worm, S.; Xiu, Q.; Zavrtanik, M.; Zhang, J.; Zhu, H.

    2016-04-01

    Charge collection properties of particle detectors made in HV-CMOS technology were investigated before and after irradiation with reactor neutrons. Two different sensor types were designed and processed in 180 and 350 nm technology by AMS. Edge-TCT and charge collection measurements with electrons from 90Sr source were employed. Diffusion of generated carriers from undepleted substrate contributes significantly to the charge collection before irradiation, while after irradiation the drift contribution prevails as shown by charge measurements at different shaping times. The depleted region at a given bias voltage was found to grow with irradiation in the fluence range of interest for strip detectors at the HL-LHC. This leads to large gains in the measured charge with respect to the one before irradiation. The increase of the depleted region was attributed to removal of effective acceptors. The evolution of depleted region with fluence was investigated and modeled. Initial studies show a small effect of short term annealing on charge collection.

  8. Charging regime of pur spinel studied by secondary electron emission

    Energy Technology Data Exchange (ETDEWEB)

    Boughariou, A., E-mail: aicha_boughariou@yahoo.fr [LaMaCoP, Université de Sfax pour le sud, Faculté des Sciences, 3038 Sfax (Tunisia); Kallel, A. [LaMaCoP, Université de Sfax pour le sud, Faculté des Sciences, 3038 Sfax (Tunisia); Blaise, G. [LPS, Université Paris-Sud XI, Batiment 510, Orsay 91405 (France)

    2013-04-01

    Insulators are currently used in high technological devices. They are chosen because of their electrical properties of insulation and their thermal properties. It is well known that the presence of space charge in an insulator is correlated with an electric breakdown. Charging phenomena of insulator were studied thanks to a scanning electron microscope (SEM) which allows the injection of few electrons doses in a large domain of energies. SEM permits also the measurements of the secondary electron emission and the induced current created in the sample holder by the charges generated in the sample. The results showed that the secondary electron emission yield (SEE) σ is a very sensitive parameter to characterize the charging state of an insulator. In this work we investigate the charging effect of insulator surfaces like pur spinel (MgAl{sub 2}O{sub 4}) during 1.1, 5 and 15 keV. The results showed that the fundamental parameter controlling the charging kinetic is the current density J{sub 0}. At low energies 1.1 and 5 keV, two different kinds of self-regulated regime (σ=1) were observed as a function of current density. At 15 keV energy, the electron emission appears to be stimulated by the current density, due to the Poole–Frenkel effect.

  9. Design and Comparative Study of Three Photovoltaic Battery Charge Control Algorithms in MATLAB/SIMULINK Environment

    OpenAIRE

    Ankur Bhattacharjee

    2012-01-01

    This paper contains the design of a three stage solar battery charge controller and a comparative study of this charge control technique with three conventional solar battery charge control techniques such as 1. Constant Current (CC) charging, 2. Two stage constant current constant voltage (CC-CV) charging technique. The analysis and the comparative study of the aforesaid charging techniques are done in MATLAB/SIMULINK environment. Here the practical data used to simulate the charge control a...

  10. Space charge studies in FFAG using the tracking code Zgoubi

    Energy Technology Data Exchange (ETDEWEB)

    Tahar, M. Haj [Brookhaven National Lab. (BNL), Upton, NY (United States); Meot, F. [Brookhaven National Lab. (BNL), Upton, NY (United States); Tsoupas, N. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-05-03

    A method is implemented in Zgoubi that allows the computation of space charge effects in 2D distributions and with some restrictions in 3D distributions. It relies on decomposing field maps or analytical elements into slices and applying a space charge kick to the particles. The aim of this study is to investigate the accuracy of this technique, its limitations/advantages by comparisons with other linear/nonlinear computation methods and codes, and to apply it to high power fixed field ring design studies.

  11. Study of nuclei' excitation in the charge exchange reactions (Draft)

    International Nuclear Information System (INIS)

    Carried out experimental and theoretical studies show, that in the nuclear charge exchange reactions there is an unique ability for study both properties and behavior of the delta-isobar in the excited nuclear environment. However for theoretical analysis of these reactions it is necessary have experimental data on nuclei charge exchange on free nucleons. It is offered the experiment of measurement dependence of inclusive cross section of the tritium nuclei charge exchange in 3He nuclei on hydrogen from transferred energy. This reaction is isotopically dependent on 3He nuclei in tritons charge exchange reaction on neutrons. Aim of proposed experiment is checking of a hypothesis believability about the delta-isobar excitation in flying nucleus, and measurement of the process intensity. Peculiarity of this experiment is application of relativistic tritons beams formed from accelerated fragments of 4He nuclei. Experimental facility presents of combination of two one-arm spectrometers: first one - time-flying spectrometer for measurement tritium nuclei impulse in beam to target with accuracy 0.3 % for 6 GeV/s and identification of tritium nuclei, the second one - magnetic spectrometer for identification and measurement of 3He nuclei impulse forming in the result of the charge exchange reaction

  12. Trigger Studies for the search of a heavy Charged Higgs

    CERN Document Server

    Haraki, Mikela

    2016-01-01

    The efficiency of different triggers for the search of a charged Higgs is studied using generator-level simulations. A charged Higgs boson with a mass heavier than the top quark mass is produced in association with a top quark and can decay to $t\\bar{b}$ $(gg\\rightarrow \\bar{t}bH^{+} / H^{+}\\rightarrow t\\bar{b}$) resulting to an all hadronic final state. In order to improve the efficiency of the triggers, several kinematic variables are examined.

  13. Charge collection efficiency studies with irradiated silicon detectors

    CERN Document Server

    Allport, P P; Casse, G; Greenall, A; Jackson, J N; Turner, P R

    2003-01-01

    Small area (1x1 cm sup 2) microstrip detectors, made with a p sup + -n diode structure on FZ silicon substrates, both with and without oxygen enrichment, have been irradiated with 24 GeV/c protons to fluences of 1.9, 2.9 and 5.1x10 sup 1 sup 4 p/cm sup 2. Their charge collection properties have been studied using a sup 1 sup 0 sup 6 Ru beta-source with a wide bandwidth current amplifier and compared with those for a non-irradiated device. The integrated charge collected at different times (10, 25, 40 and 80 ns) has been used to estimate the effect of ballistic deficit. Predictions for the reduction in charge collection efficiency expected at fluences as high as 10 sup 1 sup 5 cm sup - sup 2 are presented using a parameterization described in earlier work which also fits this data well.

  14. Children : Their Place in Organization Studies

    OpenAIRE

    Kavanagh, Donncha

    2013-01-01

    This paper argues that children and childhood constitute a ¿white space¿ in organization studies, which should now be explored, mapped and analysed.Rather than being separate, children and organization are deeply implicated in one another, which provides a rich basis for theoretical inquiry. The paper draws on Spivak's concept of the subaltern and on actor-network theory to articulate how and where organization studies might critically engage with, and find a place for, children and childhood...

  15. A STUDY ON LICHEN PLANUS IN CHILDREN

    OpenAIRE

    Neerja Puri; Asha Puri

    2013-01-01

    Introduction: Lichen planus is considered to be rare in children. However, it does not appear to be uncommon in Indian subcontinent. Aims: The study was undertaken to analyse the clinical profile of childhood lichen planus. Material and Methods: We selected 30 children with LP for the study. The children selected were below the age of 14 years of age. Results and Discussion: In our study, it was seen that that the maximum onset of disease was between 5-9 years of age and mean age of children ...

  16. Methods for studying plasma charge transport across a magnetic field

    International Nuclear Information System (INIS)

    A comparative analysis of experimental methods for the diffusion transfer of plasma charged particles accross the magnetic field at the study of its confinement effectiveness, instability effect is carried out. Considered are the methods based on the analysis of particle balance in the charge and possibilities of diffusion coefficient determination according to measuring parameters of density gradient and particle flow on the wall, rate of plasma decay after switching off ionization source radial profile of plasma density outside the active region of stationary charge. Much attension is payed to the research methods of diffusion transfer, connected with the study of propagation of periodic and aperiodic density perturbation in a plasma. Analysed is the Golubev and Granovsky method of diffusion waves and its different modifications, phase analysis method of ''test charges'' movement, as well as different modifications of correlation methods. Considered are physical preconditions of the latter and criticized is unilateral interpretation of correlation measurings, carried out in a number of works. The analysis of study possibilities of independent (non-ambipolar) diffusion of electrons and ions in a plasma in the magnetic field is executed

  17. Kelvin probe study of laterally inhomogeneous dielectric charging and charge diffusion in RF MEMS capacitive switches

    OpenAIRE

    Herfst, R.W.; Steeneken, P. G.; Schmitz, J; Mank, A.J.G.; Gils, van, S.H.

    2008-01-01

    In this paper we use scanning Kelvin probe microscopy (SKPM) to detect charge in the dielectric of RF MEMS capacitive switches. We observe a laterally inhomogeneous distribution. Laterally inhomogeneous dielectric charging leads to a narrowing of the C-V curve [1], and can lead to stiction of the membrane. The measurements show that trapped charges slowly diffuse, which reduces the inhomogeneity and shows that charge is vertically confined. From these measurements we estimate the lateral diff...

  18. Children of Immigrants Longitudinal Study (CILS)

    OpenAIRE

    Rumbaut, RG; Portes, A.

    2006-01-01

    Children of Immigrants Longitudinal Study (CILS) was designed to study the adaptation process of the immigrant second generation which is defined broadly as United States-born children with at least one foreign-born parent or children born abroad but brought at an early age to the United States. The original survey was conducted with large samples of second-generation immigrant children attending the 8th and 9th grades in public and private schools in the metropolitan areas of Miami/Ft. Laude...

  19. [Time-resolved optical studies of charge relaxation and charge transfer at electrode interfaces

    Energy Technology Data Exchange (ETDEWEB)

    1992-12-31

    Key components were identified in a quantitative model of carrier relaxation in semiconductor electrodes: nonlinear aspects of nonradiative and radiative recombination, effect of space charge field on carrier dynamics, self-absorption effects in direct gas semiconductors, and influence of surface state population kinetics on charge carrier recombination. For CdSe, the first three are operative (no direct proof of the last one). A realistic kinetic model for carrier recombination in the bulk of CdSe was used which includes important nonlinear effects, both radiative and nonradiative. The change in interfacial recombination velocity with the chemical nature of the sinterface was studied (n-CdSe/silane interfaces). Temperature effect (278 to 328 K) on fluorescence decay of n-CdSe in contact with 0.5 M KOH was found to be weak. An analytical solution was obtained for time-resolved fluoresence from electrodes under potential bias, and is being tested. Fluorescence work on a different material, CdS, indicate different recombination kinetics; this material was used to directly pump an optical transition of a surface state.

  20. Study of longitudinal dynamics in space-charge dominated beams

    Science.gov (United States)

    Tian, Kai

    Modern accelerator applications, such as heavy ion fusion drivers, pulsed neutron sources, electron injectors for high-energy linear colliders, and X-ray Free Electron Lasers, demand beams with high intensity, low emittance and small energy spread. At low (non-relativistic) energies, the "electrostatic", collective interactions from space-charge forces existing in such intense beams play the dominant role; we characterize these beams as space-charge dominated beams. This dissertation presents numerous new findings on the longitudinal dynamics of a space-charge dominated beam, particularly on the propagation of density perturbations. In order to fully understand the complex physics of longitudinal space-charge waves, we combine the results of theory, computer simulation, and experiment. In the Long Solenoid Experimental system (LSE), with numerous diagnostic tools and techniques, we have, for the first time, experimentally measured the detailed energy profiles of longitudinal space-charge waves at different locations, both near the beam source and at the end of the transport system. Along with the current profiles, we have a complete set of experimental data for the propagation of space-charge waves. We compare these measured results to a 1-D theory and find better agreement for beams with perturbations in the linear regime, where the perturbation strength is less than 10%, than those with nonlinear perturbations. Using fast imaging techniques that we newly developed, we have, for the first time, obtained the progressive time-resolved images of longitudinal slices of a space-charge dominated beam. These images not only provide us time-resolved transverse density distribution of the beam, but also enable us to take time-resolved transverse phase space measurement using computerized tomography. By combining this information with the longitudinal energy measurement, we have, for the first time, experimentally constructed the full 6-D phase space. Part of the results

  1. Design and Comparative Study of Three Photovoltaic Battery Charge Control Algorithms in MATLAB/SIMULINK Environment

    Directory of Open Access Journals (Sweden)

    Ankur Bhattacharjee

    2012-09-01

    Full Text Available This paper contains the design of a three stagesolar battery charge controller and a comparativestudy of this charge control technique with threeconventional solar battery charge controltechniques such as 1. Constant Current (CCcharging, 2. Two stage constant current constantvoltage (CC-CV charging technique. Theanalysis and the comparative study of theaforesaid charging techniques are done inMATLAB/SIMULINK environment. Here thepractical data used to simulate the charge controlalgorithms are based on a 12Volts 7Ah Sealedlead acid battery.

  2. Case Studies of Environmental Risks to Children.

    Science.gov (United States)

    Goldman, Lynn R.

    1995-01-01

    Presents case studies on children's exposure to pesticides, including risks through the use of the insecticide aldicarb on bananas, the home use of diazinon, and the use of interior house paint containing mercury. These cases illustrate how regulatory agencies, parents, health-care providers, and others who come into contact with children have…

  3. Children's Friendship Development: A Comparative Study

    Science.gov (United States)

    Yu, SeonYeong; Ostrosky, Michaelene M.; Fowler, Susan A.

    2011-01-01

    Establishing friendships is an important developmental goal of early childhood, but little research has addressed ways in which parents support the friendship development of their young children with disabilities. The purpose of this survey study was to explore the support strategies that parents use to facilitate their children's friendships.…

  4. Design study of an upgraded charge breeder for ISOLDE

    CERN Document Server

    Shornikov, A; Wenander, F; Pikin, A

    2013-01-01

    In this work we present our progress in the design study of a new Electron Beam Ion Source (EBIS) to be installed as a charge breeder for reacceleration of rare ions at ISOLDE. The work is triggered by the HIE-ISOLDE upgrade {[}1] and the planned TSR@ISOLDE project {[}2]. To fulfill the requests of the user community the new EBIS should reach an electron beam density of 10(4) A/cm(2) at electron energies up to 150 key and, provide UHV environment and ion cooling in the breeding region to ensure confinement of the ions long enough to reach the requested charge states. We report on the established design parameters and first prototyping steps towards production and testing of suitable equipment. (C) 2013 Elsevier B.V. All rights reserved.

  5. Computational studies on nitratoethylnitramine (NENA), its tautomers and charged forms

    International Nuclear Information System (INIS)

    An energetic material, nitratoethylnitramine (NENA), its tautomers and also its charged forms are considered quantum chemically, using various basis sets at the levels of ab initio and density functional theories (DFT). NENA has been found to be sensitive to negative charge development, resulting in rupture of O-NO2 bond. Also conformational and molecular dynamics (MD) studies have been performed on NENA. Various geometrical parameters, energies and infrared spectra have been obtained and discussed. Also, calculations indicate that s-cis conformation of NENA is slightly more stable than the s-trans and the tautomers of it have very comparable total energy values to NENA. On the other hand, on the basis of homolytic bond dissociation energies (BDE) for O-NO2 bond in the structures, it is clear that the presence of the tautomers in the bulk of NENA somewhat should decrease its sensitivity

  6. Microscopic optical potentials - study of charge-exchange reactions

    International Nuclear Information System (INIS)

    The present thesis is engaged in two different aspects of direct nuclear reactions, namely on the one hand in the microscopic calculation of the imaginary optical potential for the elastic alpha-nucleus scattering as well on the other hand in the microscopic analysis of giant resonance states which are excited by (p,n) and (n,p) charge-exchange reactions. In the first part in the framework of the nuclear structure approximation to the optical potential a microscopic calculation of the imaginary part of the optical potential for α40Ca scattering at Esub(α) = 31 and 100 MeV is performed. In the second part the 208Pb(p,n) and 208Pb(n,p) charge-exchange reactions are studied at low ( E 100 MeV) incident energies. (orig./HS)

  7. Monte Carlo Studies of Charge Transport Below the Mobility Edge

    OpenAIRE

    Jakobsson, Mattias

    2012-01-01

    Charge transport below the mobility edge, where the charge carriers are hopping between localized electronic states, is the dominant charge transport mechanism in a wide range of disordered materials. This type of incoherent charge transport is fundamentally different from the coherent charge transport in ordered crystalline materials. With the advent of organic electronics, where small organic molecules or polymers replace traditional inorganic semiconductors, the interest for this type of h...

  8. Neutron-Induced Charged Particle Studies at LANSCE

    Science.gov (United States)

    Lee, Hye Young; Haight, Robert C.

    2014-09-01

    Direct measurements on neutron-induced charged particle reactions are of interest for nuclear astrophysics and applied nuclear energy. LANSCE (Los Alamos Neutron Science Center) produces neutrons in energy of thermal to several hundreds MeV. There has been an effort at LANSCE to upgrade neutron-induced charged particle detection technique, which follows on (n,z) measurements made previously here and will have improved capabilities including larger solid angles, higher efficiency, and better signal to background ratios. For studying cross sections of low-energy neutron induced alpha reactions, Frisch-gridded ionization chamber is designed with segmented anodes for improving signal-to-noise ratio near reaction thresholds. Since double-differential cross sections on (n,p) and (n,a) reactions up to tens of MeV provide important information on deducing nuclear level density, the ionization chamber will be coupled with silicon strip detectors (DSSD) in order to stop energetic charged particles. In this paper, we will present the status of this development including the progress on detector design, calibrations and Monte Carlo simulations. This work is funded by the US Department of Energy - Los Alamos National Security, LLC under Contract DE-AC52-06NA25396.

  9. Children and Clinical Studies: Why Clinical Studies Are Important

    Medline Plus

    Full Text Available ... Research Research Resources Research Meeting Summaries Technology Transfer Clinical Trials What Are Clinical Trials? Children & Clinical Studies NHLBI Trials Clinical Trial Websites ...

  10. Design and Comparative Study of Three Photovoltaic Battery Charge Control Algorithms in MATLAB/SIMULINK Environment

    Directory of Open Access Journals (Sweden)

    Ankur Bhattacharjee

    2012-09-01

    Full Text Available This paper contains the design of a three stage solar battery charge controller and a comparative study of this charge control technique with three conventional solar battery charge control techniques such as 1. Constant Current (CC charging, 2. Two stage constant current constant voltage (CC-CV charging technique. The analysis and the comparative study of the aforesaid charging techniques are done in MATLAB/SIMULINK environment. Here the practical data used to simulate the charge control algorithms are based on a 12Volts 7Ah Sealed lead acid battery.

  11. Numerical study of superradiant instability for charged stringy black hole–mirror system

    Directory of Open Access Journals (Sweden)

    Ran Li

    2015-01-01

    Full Text Available We numerically study the superradiant instability of charged massless scalar field in the background of charged stringy black hole with mirror-like boundary condition. We compare the numerical result with the previous analytical result and show the dependencies of this instability upon various values of black hole charge Q, scalar field charge q, and mirror radius rm. Especially, we have observed that imaginary part of BQN frequencies grows with the scalar field charge q rapidly.

  12. Clinical Study on Ocular Trauma in Children

    Institute of Scientific and Technical Information of China (English)

    Zicai Huang; Hongni Li; Yixia Huang; Zhongxia Zhou

    2002-01-01

    Purpose: To investigate the clinical characteristics of ocular trauma in children and put forward the major treatment and prevention of ocular trauma in children.Methods: To analyze the clinical data by 77 eyes in 77 cases of ocular trauma in children from April 1999 to February 2002. Results: The male and female were in the ratio of 2.21: 1. Right eye ocular traumas were more than left ones. Ocular penetrating trauma was 83.12% and blunt trauma 12.99%. 41 cases (53.25%) were injured by themselves while 33 cases by others. 90.91% patients came from the countryside.Conclusion: The rate of blindness of children with ocular trauma could be reduced by prompt treatment. The study indicated that ocular trauma preventive publicity should be faced in the countryside in order to improve the understanding of the severity of ocular trauma and treat it as a social problem.

  13. Children's Schooling and Parents' Investment in Children: Evidence from the Head Start Impact Study

    OpenAIRE

    Alexander M. Gelber; Adam Isen

    2011-01-01

    Parents may have important effects on their children, but little work in economics explores whether children's schooling opportunities crowd out or encourage parents' investment in children. We analyze data from the Head Start Impact Study, which granted randomly-chosen preschool-aged children the opportunity to attend Head Start. We find that Head Start causes a substantial increase in parents' involvement with their children--such as time spent reading to children, math activities, or days ...

  14. Sign Language Studies with Chimpanzees and Children.

    Science.gov (United States)

    Van Cantfort, Thomas E.; Rimpau, James B.

    1982-01-01

    Reviews methodologies of sign language studies with chimpanzees and compares major findings of those studies with studies of human children. Considers relevance of input conditions for language acquisition, evidence used to demonstrate linguistic achievements, and application of rigorous testing procedures in developmental psycholinguistics.…

  15. Study on space charge compensation in negative hydrogen ion beam

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, A. L.; Chen, J. E. [University of Chinese Academy of Sciences, Beijing 100049 (China); State Key Laboratory of Nuclear Physics and Technology, Institute of Heavy Ion Physics, School of Physics, Peking University, Beijing 100871 (China); Peng, S. X., E-mail: sxpeng@pku.edu.cn; Ren, H. T.; Zhang, T.; Zhang, J. F.; Xu, Y.; Guo, Z. Y. [State Key Laboratory of Nuclear Physics and Technology, Institute of Heavy Ion Physics, School of Physics, Peking University, Beijing 100871 (China)

    2016-02-15

    Negative hydrogen ion beam can be compensated by the trapping of ions into the beam potential. When the beam propagates through a neutral gas, these ions arise due to gas ionization by the beam ions. However, the high neutral gas pressure may cause serious negative hydrogen ion beam loss, while low neutral gas pressure may lead to ion-ion instability and decompensation. To better understand the space charge compensation processes within a negative hydrogen beam, experimental study and numerical simulation were carried out at Peking University (PKU). The simulation code for negative hydrogen ion beam is improved from a 2D particle-in-cell-Monte Carlo collision code which has been successfully applied to H{sup +} beam compensated with Ar gas. Impacts among ions, electrons, and neutral gases in negative hydrogen beam compensation processes are carefully treated. The results of the beam simulations were compared with current and emittance measurements of an H{sup −} beam from a 2.45 GHz microwave driven H{sup −} ion source in PKU. Compensation gas was injected directly into the beam transport region to modify the space charge compensation degree. The experimental results were in good agreement with the simulation results.

  16. Study on space charge compensation in negative hydrogen ion beam

    Science.gov (United States)

    Zhang, A. L.; Peng, S. X.; Ren, H. T.; Zhang, T.; Zhang, J. F.; Xu, Y.; Guo, Z. Y.; Chen, J. E.

    2016-02-01

    Negative hydrogen ion beam can be compensated by the trapping of ions into the beam potential. When the beam propagates through a neutral gas, these ions arise due to gas ionization by the beam ions. However, the high neutral gas pressure may cause serious negative hydrogen ion beam loss, while low neutral gas pressure may lead to ion-ion instability and decompensation. To better understand the space charge compensation processes within a negative hydrogen beam, experimental study and numerical simulation were carried out at Peking University (PKU). The simulation code for negative hydrogen ion beam is improved from a 2D particle-in-cell-Monte Carlo collision code which has been successfully applied to H+ beam compensated with Ar gas. Impacts among ions, electrons, and neutral gases in negative hydrogen beam compensation processes are carefully treated. The results of the beam simulations were compared with current and emittance measurements of an H- beam from a 2.45 GHz microwave driven H- ion source in PKU. Compensation gas was injected directly into the beam transport region to modify the space charge compensation degree. The experimental results were in good agreement with the simulation results.

  17. Study on space charge compensation in negative hydrogen ion beam

    International Nuclear Information System (INIS)

    Negative hydrogen ion beam can be compensated by the trapping of ions into the beam potential. When the beam propagates through a neutral gas, these ions arise due to gas ionization by the beam ions. However, the high neutral gas pressure may cause serious negative hydrogen ion beam loss, while low neutral gas pressure may lead to ion-ion instability and decompensation. To better understand the space charge compensation processes within a negative hydrogen beam, experimental study and numerical simulation were carried out at Peking University (PKU). The simulation code for negative hydrogen ion beam is improved from a 2D particle-in-cell-Monte Carlo collision code which has been successfully applied to H+ beam compensated with Ar gas. Impacts among ions, electrons, and neutral gases in negative hydrogen beam compensation processes are carefully treated. The results of the beam simulations were compared with current and emittance measurements of an H− beam from a 2.45 GHz microwave driven H− ion source in PKU. Compensation gas was injected directly into the beam transport region to modify the space charge compensation degree. The experimental results were in good agreement with the simulation results

  18. Advanced stratified charge rotary aircraft engine design study

    Science.gov (United States)

    Badgley, P.; Berkowitz, M.; Jones, C.; Myers, D.; Norwood, E.; Pratt, W. B.; Ellis, D. R.; Huggins, G.; Mueller, A.; Hembrey, J. H.

    1982-01-01

    A technology base of new developments which offered potential benefits to a general aviation engine was compiled and ranked. Using design approaches selected from the ranked list, conceptual design studies were performed of an advanced and a highly advanced engine sized to provide 186/250 shaft Kw/HP under cruise conditions at 7620/25,000 m/ft altitude. These are turbocharged, direct-injected stratified charge engines intended for commercial introduction in the early 1990's. The engine descriptive data includes tables, curves, and drawings depicting configuration, performance, weights and sizes, heat rejection, ignition and fuel injection system descriptions, maintenance requirements, and scaling data for varying power. An engine-airframe integration study of the resulting engines in advanced airframes was performed on a comparative basis with current production type engines. The results show airplane performance, costs, noise & installation factors. The rotary-engined airplanes display substantial improvements over the baseline, including 30 to 35% lower fuel usage.

  19. The National Children's Study: a 21-year prospective study of 100,000 American children.

    Science.gov (United States)

    Landrigan, Philip J; Trasande, Leonardo; Thorpe, Lorna E; Gwynn, Charon; Lioy, Paul J; D'Alton, Mary E; Lipkind, Heather S; Swanson, James; Wadhwa, Pathik D; Clark, Edward B; Rauh, Virginia A; Perera, Frederica P; Susser, Ezra

    2006-11-01

    Prospective, multiyear epidemiologic studies have proven to be highly effective in discovering preventable risk factors for chronic disease. Investigations such as the Framingham Heart Study have produced blueprints for disease prevention and saved millions of lives and billions of dollars. To discover preventable environmental risk factors for disease in children, the US Congress directed the National Institute of Child Health and Human Development, through the Children's Health Act of 2000, to conduct the National Children's Study. The National Children's Study is hypothesis-driven and will seek information on environmental risks and individual susceptibility factors for asthma, birth defects, dyslexia, attention-deficit/hyperactivity disorder, autism, schizophrenia, and obesity, as well as for adverse birth outcomes. It will be conducted in a nationally representative, prospective cohort of 100,000 US-born children. Children will be followed from conception to 21 years of age. Environmental exposures (chemical, physical, biological, and psychosocial) will be assessed repeatedly during pregnancy and throughout childhood in children's homes, schools, and communities. Chemical assays will be performed by the Centers for Disease Control and Prevention, and banks of biological and environmental samples will be established for future analyses. Genetic material will be collected on each mother and child and banked to permit study of gene-environment interactions. Recruitment is scheduled to begin in 2007 at 7 Vanguard Sites and will extend to 105 sites across the United States. The National Children's Study will generate multiple satellite studies that explore methodologic issues, etiologic questions, and potential interventions. It will provide training for the next generation of researchers and practitioners in environmental pediatrics and will link to planned and ongoing prospective birth cohort studies in other nations. Data from the National Children's Study will

  20. The Study on Differential Charges of Universities in China

    Institute of Scientific and Technical Information of China (English)

    WEN Xiao-zheng

    2005-01-01

    This paper mainly discusses the "double-track charge" system (price prejudice charge system) in theory and practice. The author explains and analyzes the "differential charges phenomenon" of universities in China by taking "Pareto optimality" as regulation standard and "Darwin optimality" as empirical standard, combining regulation standard with practice standard, realistic standard of value judgment with ultimate standard, and fairness with efficiency. This paper provides theoretical reference and an operation platform for application and implementation differential charges and the containment of corruption in college enrollment.

  1. Study of Charged Pion Photoproduction on Deuteron with Tagged Photons

    Institute of Scientific and Technical Information of China (English)

    HAN Yun-cheng; N.Chiga; Y.Fujii; K.Futatsukawa; O.Hashimoto; K.Hirose; T.Ishikawa; H.Kanda; M.Kaneta; D.Kawama; Konno; MA Yue; K.Maeda; T.Maruta; N.Maruyama; A.Matsumura; Y.Miyagi; K.Miwa; S.N.Nakamura; A.Sasaki; H.Shimizu; K.Shirotori; K.Suzuki; T.Tamae; H.Tamura; K.Tsukada; WANG Tie-shan; H.Yarnazaki

    2009-01-01

    The reactions γd→π~- pp and γd→npπ~+π~- have been studied in an energy range from 0.8 to 1.1 GeV at the tagged photon facility of Laboratory of Nuclear Science,T ohoku University.Charged pions and protons in the final state were measured by using the Neutral Kaon Spectrometer (NKS2).The analysis of the γd→π~- pp was mainly used to check the acceptance of the NKS2 and to calibrate the tagged photon energy.The photoproduction of the Δ~(++)Δ~- was identified in the γd→npπ~+π~- reaction.Since the data analyses are still in progress,we issue an interim report and preliminary results.

  2. Pathways to Language: A Naturalistic Study of Children with Williams Syndrome and Children with Down Syndrome

    Science.gov (United States)

    Levy, Yonata; Eilam, Ariela

    2013-01-01

    This is a naturalistic study of the development of language in Hebrew-speaking children with Williams syndrome (WS) and children with Down syndrome (DS), whose MLU extended from 1[multiplied by]0 to 4[multiplied by]4. Developmental curves over the entire span of data collection revealed minor differences between children with WS, children with DS,…

  3. Erythema infectiosumin children: A clinical study

    Directory of Open Access Journals (Sweden)

    Prćić Šonja

    2006-01-01

    Full Text Available Erythema infectiositm is a childhood illness characterized by mild constitutional symptoms and a blotchy or maculo-papular lacy rash on the cheeks (slapped - cheek spreading primarily to the extremities and trunk. The disease- is-caused by human parvovirus B19. Erythema infectiosum epidemics occur in a cyclic fashion, mostly during winter and spring months. The diagnosis of erythema infectiosum is usually based on the appearance and pattern of the rash. The aim of our study was to establish the frequency and clinical characteristics of erythema infectiosum in children, in the period between 2000 and 2004 at the Institute of Child and Youth Health Care, Department of Dermatology, Novi Sad. There were 0.23% of children with a clinical picture of infectious erythema. There was an outbreak of erythema infectiosum from December 2001 to September 2002. The highest number of cases was detected in April and May of 2002. from 2003 to 2004, no cases with infekctious erythema were diagnosed. The average age of infected children was 7.38. Female children were affected slightly more often than male (56.41%:43.58%. Pruritus was detected in 10.26% of children. The most constant clinical sign was reticular exanthema on the limbs, present in 100% of cases, followed by 89.74% of cheek exanthema, while limb and trunk exanthema was present in 7.68% of children. Adenopathies and mild constitutional symptoms were present in 5.12% of children. No complications were recorded in any of the cases. .

  4. Study of television viewing habits in children.

    Science.gov (United States)

    Mukherjee, Sharmila Banerjee; Gupta, Yogita; Aneja, Satinder

    2014-11-01

    Previous studies from developing countries have reported that Television (TV) viewing, if excessive and of poor quality has a proven negative influence on child health. Indian studies on this subject are few. The present study aimed at determining TV viewing habits of children and their families as well as parental perspectives on the impact of TV on child health using a provider completed indigenously developed questionnaire in Hindi. The study group comprised of 109 children attending a government hospital who belonged predominantly to lower socio-economic strata with poor maternal literacy. It was observed that 100 % children watched excessive TV (> 2 h daily), with majority viewing unsupervised and low quality content. There were minimal parental restrictions and no active discussion regarding contents. Negative impact was found on play, hobbies, sleep hygiene and eating habits in most children. Most parents were unaware of unhealthy viewing and the associated deleterious effects. As pediatricians we need to enquire about TV viewing habits routinely and educate parents about appropriate TV viewing. PMID:24682808

  5. Theoretical study of the central depression of nuclear charge density distribution by electron scattering

    International Nuclear Information System (INIS)

    The charge form factors of elastic electron scattering for isotones with N=20 and N=28 are calculated using the phase-shift analysis method, with corresponding charge density distributions from relativistic mean-field theory. The results show that there are sharp variations at the inner parts of charge distributions with the proton number decreasing. The corresponding charge form factors are divided into two groups because of the unique properties of the s-states wave functions, though the proton numbers change uniformly in two isotonic chains. Meanwhile, the shift regularities of the minima are also discussed, and we give a clear relation between the minima of the charge form factors and the corresponding charge radii. This relation is caused by the diffraction effect of the electron. Under this conclusion, we calculate the charge density distributions and the charge form factors of the A=44 nuclei chain. The results are also useful for studying the central depression in light exotic nuclei. (authors)

  6. Children and their parents : A comparative study of the legal position of children

    OpenAIRE

    Vonk, M.J.

    2007-01-01

    This is a book about children and their parents. There are many different kinds of children and at least about as many different kinds of parents. In addition to the many different disciplines that study children and their parents, such as sociology, psychology, child studies and gender studies, to name but a few, this study concerns a legal question with regard to the parent-child relationship, namely how the law assigns parents to children. This subject is approached in a comparative legal ...

  7. A charge-density study of crystalline beryllium

    International Nuclear Information System (INIS)

    The X-ray structure factors for crystalline beryllium measured by Brown [Phil. Mag. (1972), 26, 1377] have been analyzed with multipole deformation functions for charge-density information. Single exponential radial functions were used for the valence charge density. A valence monopole plus the three harmonics, P35(cos theta) sin 3phi, P6(cos theta) and P37(cos theta) sin 3phi, provide a least-squares fit to the data with Rsub(w)=0.0081. The superposition of these density functions describes a bonding charge density between Be atoms along the c axis through the tetrahedral vacancy. The results reported here are in qualitative agreement with a recent pseudo-potential calculation of metallic beryllium. The final residuals in the analysis are largest at high sin theta/lambda values. This suggests that core charge deformation is present and/or anharmonic motion of the nuclei is appreciable. (Auth.)

  8. A Monte Carlo study of charge transfer in DNA

    OpenAIRE

    Jakobsson, Mattias; Stafström, Sven

    2008-01-01

    A model describing charge (hole) transport in DNA has been developed. The individual charge transfer steps in the transport process are described by Marcus theory modified to account for electron delocalization over adjacent identical nucleobases. Such a modification, as well as introducing a distance dependence in the reorganization energy, is necessary in order to reach an agreement with the observed transfer rates in well defined model systems to DNA. Using previously published results as ...

  9. Children and media: a cultural studies approach

    OpenAIRE

    D av i d B u c k i n g h a m

    2012-01-01

    Defying the traditional psychology understanding on what are the effects of the media and also the researches made on the subject, the present article offers an approach to the study of the relationship between children and the media, focusing mainly on television. We retrace the Cultural Studies perspective, although the researches from the Birmingham Centre have not worked over such age group.The work includes the model of the cultural circuit, it refuses to understand meaning as something ...

  10. A study of inclusive charged current neutrino interactions in deuterium

    International Nuclear Information System (INIS)

    In this thesis the results of an analysis of inclusive neutrino and antineutrino interaction on deuterium nuclei are presented. The use of deuterium as a target provides a mean to study proton and neutron scattering separately. The presently accepted theory of electro-weak interactions is reviewed. Applications of the quark-parton model in the context of deep-inelastic neutrino interactions on nucleons are summarized. The concept of scaling and its consequences are treated, together with some sources of violation of scaling. The properties of the CERN wide-band neutrino beam and an overview of the elements of this beam are given. The method to determine the energy distribution and the composition of the neutrino and antineutrino beam is described. The technique employed to separate neutrino interactions on protons and neutrons is discussed. Results of the measurement of the total nucleon charged-current cross-sections and differential cross-sections are presented. The relative contributions of quarks and antiquarks to the neutrino cross-sections are deduced from y-distributions and compared to those obtained from the total cross-section measurements. Finally, the analysis of the structure functions is given. (Auth.)

  11. Study of a large acceptance charged particle detector

    International Nuclear Information System (INIS)

    We investigated basic characteristics of a new detector system, which has been designed to be used for nuclear data measurements. The detector has a large acceptance to cover a wide range of charged particle energies. The detector consists of crystal detectors and plastic scintillators. In this detector, energy measurements are carried out by adopting the pulse-height method for low-energy particles and for high-energy particles the time of flight (TOF) technique. The low-energy detector (crystals) plays also as a degrader for high-energy particles. One of important issues is the non-linearity of scintillation output for heavy ions of crystal detectors. The other issue is the deviation of a particle trajectory due to the multiple-scattering in the detector material. In the present study, we measured the scintillation output of detectors and the multiple-scattering effect on the TOF detection efficiency. Experiments were carried out at National Inst. of Radiological Sciences-Heavy Ion Medical Accelerator in Chiba (NIRS-HIMAC) for a crystal detector system by using protons and Ar ions. Finally, the scintillation nonlinearity has been determined. As for the multiple-scattering effect, we found that both of simulations, GEANT4 and PHITS tend to underestimate. (author)

  12. Charge collection efficiency of GaAs detectors studied with low-energy heavy charged particles

    CERN Document Server

    Bates, R; Linhart, V; O'Shea, V; Pospísil, S; Raine, C; Smith, K; Sinor, M; Wilhelm, I

    1999-01-01

    Epitaxially grown GaAs layers have recently been produced with sufficient thickness and low enough free carrier concentration to permit their use as radiation detectors. Initial tests have shown that the epi-material behaves as a classical semiconductor as the depletion behaviour follows the square root dependency on the applied bias. This article presents the results of measurements of the growth of the active depletion depth with increasing bias using low-energy protons and alpha particles as probes for various depths and their comparison to values extrapolated from capacitance measurements. From the proton and alpha particle spectroscopic measurements, an active depth of detector material that collects 100% of the charge generated inside it was determined. The consistency of these results with independent capacitance measurements supports the idea that the GaAs epi-material behaves as a classical semiconductor. (author)

  13. Cytogenetic Studies in Children with Developmental Delay

    Directory of Open Access Journals (Sweden)

    Hassan S.A. El-Dawi, *El-Sayed G. Khedr, *Tarek A. Atia, **Hassan Ali

    2008-03-01

    Full Text Available Introduction: Developmental delay (DD could be syndromic or non-syndromic, and collectively it affects 10% of all children. There are numerous causes of DD that could be genetical, hormonal and/or neurological. The frequency of defected chromosomal anomalies in patients with DD is variable and estimates between 9% and 36%. However, the accurate diagnosis needs further tests based on the information gather from parents and the findings on physical examination. Objective: We aim to evaluate the pattern of chromosomal abnormalities in children with non-syndromic DD, in order to detect the treatable cases, and offering an appropriate genetic counseling. Methodology: 50 children suffering from DD with or without mental retardation(MR and/or congenital anomalies were subjected to the present study. Additionally, another 50 normally developed children were considered as control group. Peripheral blood samples were collected, cultured, harvested, metaphase spread and then chromosomes were stained for G-banding using Trypsin-Giemsa technique. Chromosomes were analyzed, metaphase spreads were captured, and karyotyping has been done. Result: Seven cases (14% out of the 50 affected children carried structural chromosomal rearrangements. Six (85.7% out of the seven structural chromosomal abnormalities were detected in autosomal chromosomes and one (14.3% in sex chromosome. Surprisingly, we have found a case (2% carrying pericentric inversion of chromosome 3 within the normal control group. Conclusions: Chromosomal studies are valuable in detecting such cases with DD. Prenatal genetic diagnosis is of clinical importance to prevent and offer genetic counseling. Additionally, small proportion of apparently normal population could carry some types of structural chromosomal anomalies

  14. Observational study of children with aerophagia.

    Science.gov (United States)

    Loening-Baucke, Vera; Swidsinski, Alexander

    2008-09-01

    Aerophagia is a rare disorder in children. The diagnosis is often delayed, especially when it occurs concomitantly with constipation. The aim of this report is to increase awareness about aerophagia. This study describes 2 girls and 7 boys, 2 to 10.4 years of age, with functional constipation and gaseous abdominal distention. The abdomen was visibly distended, nontender, and tympanitic in all. Documenting less distention on awakening helped to make the diagnosis. Air swallowing, belching, and flatulence were infrequently reported. The rectal examination often revealed a dilated rectal ampulla filled with gas or stool and gas. The abdominal X-ray showed gaseous distention of the colon in all and of the stomach and small bowel in 8 children. Treatment consisted of educating parents and children about air sucking and swallowing, encouraging the children to stop the excessive air swallowing, and suggesting to them not to use drinking straws and not to drink carbonated beverages. The aerophagia resolved in all in 2 to 20 months (mean=8 months). PMID:18445758

  15. Children and media: a cultural studies approach

    Directory of Open Access Journals (Sweden)

    D av i d B u c k i n g h a m

    2012-06-01

    Full Text Available Defying the traditional psychology understanding on what are the effects of the media and also the researches made on the subject, the present article offers an approach to the study of the relationship between children and the media, focusing mainly on television. We retrace the Cultural Studies perspective, although the researches from the Birmingham Centre have not worked over such age group.The work includes the model of the cultural circuit, it refuses to understand meaning as something that the media distributes to a passive audience and it states that the audience has an active role but works under conditions strange to its own choice. Regarding children, their relationship with the media is structured and restrained by broader social discourses and institutions that try to define childhood in some given ways.

  16. Charge transfer properties of pentacene adsorbed on silver: DFT study

    International Nuclear Information System (INIS)

    Charge transfer properties of pentacene adsorbed on silver is investigated using DFT methods. Optimized geometry of pentacene after adsorption on silver indicates distortion in hexagonal structure of the ring close to the silver cluster and deviations in co-planarity of carbon atoms due to the variations in bond angles and dihedral angles. Theoretically simulated absorption spectrum has a symmetric surface plasmon resonance peak around 486nm corresponding to the transfer of charge from HOMO-2 to LUMO. Theoretical SERS confirms the process of adsorption, tilted orientation of pentacene on silver surface and the charge transfers reported. Localization of electron density arising from redistribution of electrostatic potential together with a reduced bandgap of pentacene after adsorption on silver suggests its utility in the design of electro active organic semiconducting devices

  17. A Study of Charged Current Single Charged Pion Productions on Carbon in a Few-GeV Neutrino Beam

    Energy Technology Data Exchange (ETDEWEB)

    Hiraide, Katsuki; /Kyoto U.

    2009-01-01

    Understanding single charged pion production via neutrino-nucleus charged current interaction in the neutrino energy region of a few GeV is essential for future neutrino oscillation experiments since this process is a dominant background for {nu}{sub {mu}} {yields} {nu}{sub x} oscillation measurements. There are two contributions to this process: single pion production via baryonic resonance ({nu}{sub {mu}}N {yields} {mu}{sup -} N{pi}{sup +}) and coherent pion production interacting with the entire nucleus ({nu}{sub {mu}}A {yields} {mu}{sup -} A{pi}{sup +}), where N is nucleon in the nucleus and A is the nucleus. The purpose of the study presented in this thesis is a precise measurement of charged current single charged pion productions, resonant and coherent pion productions, with a good final state separation in the neutrino energy region of a few GeV. In this thesis, we focus on the study of charged current coherent pion production from muon neutrinos scattering on carbon, {nu}{sub {mu}} {sup 12}C {yields} {mu}{sup -12}C{pi}{sup +}, in the SciBooNE experiment. This is motivated by the fact that without measuring this component first, the precise determination of resonant pion production cross section can not be achieved since the contribution of coherent pion production in the region of small muon scattering angle is not small. Furthermore, the coherent process is particularly interesting because it is deeply rooted in fundamental physics via Adler's partially conserved axial-vector current theorem. We took data from June 2007 until August 2008, in both the neutrino and antineutrino beam. In total, 2.52 x 10{sup 20} protons on target were collected. We have performed a search for charged current coherent pion production by using SciBooNE's full neutrino data set, corresponding to 0.99 x 10{sup 20} protons on target. No evidence for coherent pion production is observed. We set 90% confidence level upper limits on the cross section ratio of charged

  18. A Study of Charged Current Single Charged Pion Productions on Carbon in a Few-GeV Neutrino Beam

    Energy Technology Data Exchange (ETDEWEB)

    Hiraide, Katsuki [Kyoto Univ. (Japan)

    2009-01-01

    Understanding single charged pion production via neutrino-nucleus charged current interaction in the neutrino energy region of a few GeV is essential for future neutrino oscillation experiments since this process is a dominant background for vμ → vx oscillation measurements. There are two contributions to this process: single pion production via baryonic resonance (vμN → μ-+) and coherent pion production interacting with the entire nucleus (vμA → μ-+), where N is nucleon in the nucleus and A is the nucleus. The purpose of the study presented in this thesis is a precise measurement of charged current single charged pion productions, resonant and coherent pion productions, with a good final state separation in the neutrino energy region of a few GeV. In this thesis, we focus on the study of charged current coherent pion production from muon neutrinos scattering on carbon, vμ 12C → μ-12+, in the SciBooNE experiment. This is motivated by the fact that without measuring this component first, the precise determination of resonant pion production cross section can not be achieved since the contribution of coherent pion production in the region of small muon scattering angle is not small. Furthermore, the coherent process is particularly interesting because it is deeply rooted in fundamental physics via Adler's partially conserved axial-vector current theorem. We took data from June 2007 until August 2008, in both the neutrino and antineutrino beam. In total, 2.52 x 1020 protons on target were collected. We have performed a search for charged current coherent pion production by using SciBooNE's full neutrino data set, corresponding to 0.99 x 1020 protons on target. No evidence for coherent pion production is observed. We set 90% confidence level upper limits on the cross section ratio

  19. Nail disorders in children, a clinical study

    Directory of Open Access Journals (Sweden)

    Ayşe Akbaş

    2016-04-01

    Full Text Available Introduction: Aims of the study to investigate the frequency and the nature ofnail disorders in children significant clinical data is available. Nail disorders although common in children in some parts of our country. This study was carried out to document the clinical and demographic pattern of nail disorders in a dermatology outpatient clinic of a pediatric hospital in Ankara, Turkey. Material and Methods: All consecutive patients a total of 3000 children from age 0-16 were admitted to dermatology outpatient clinic of Ankara Pediatric Hematology and Oncology Education and Research Hospital during January 2011 to December 2011 were studied and retrospectively evaluated for age, gender, drug use, diseases, systemic or genetic disorders and demographic features. Diagnostic evaluation results were noted and patients were categorized for demographic features and diagnosis. Results: These 133 patients (M: F 58:75, %44 vs 56, respectively were under 16 years of age and have 17 different dermatological disorders related with nail symptoms. Fifty three of (39,8% these patient were under 2 years of age, 31 (23.3% were between 3-5 years, 30 (22.5% were between 6-11 years old, 19 of 133 (14%, 2 were between 11-16 years of age. Through all of ages and independent of gender the most etiologies of nail disorders were, onychomadesis, paronychia, onycholysis, onychomycosis and systemic nail presentation of systemic dermatosis. Conclusion: Nail disorders are different in children than in adults. In our study, the first 5 years of age was found in 53% of nail disorders. Nail disorders are uncommon but may be seen as a part of a systemic disease and may be associated with cosmetic and psychologic problem.

  20. DFT Study on the Effect of Different Peripheral Chains on Charge Transport Properties of Triphenylene Derivatives

    Institute of Scientific and Technical Information of China (English)

    CHEN,Jun-Rong; CAI,Jing; XU,Bu-Yi; LI,Quan; ZHAO,Ke-Qing

    2008-01-01

    Based on the semi-classical model of the charge transport, theoretical studies on the effect of different periph-eral chains including alkynyl on charge transport properties of triphenylene have been carried out using density functional theory (DFT) at the level of B3LYP/6-31G**. The results indicate that all the title compounds are ad-vantageous to the charge transport. The introduction of amide RCONH to the discotic ring of triphenylene can raise the positive charge transport rate largely, and introduction of ester in peripheral chains is helpful to the positive charge transport and negative charge transport. The positive charge transport properties of monosubstituted triphenylene are better than those of disubstituted and trisubstituted triphenylenes obviously.

  1. A Different Approach to Studying the Charge and Discharge of a Capacitor without an Oscilloscope

    Science.gov (United States)

    Ladino, L. A.

    2013-01-01

    A different method to study the charging and discharging processes of a capacitor is presented. The method only requires a high impedance voltmeter. The charging and discharging processes of a capacitor are usually studied experimentally using an oscilloscope and, therefore, both processes are studied as a function of time. The approach presented…

  2. The theoretical study of charge transfer through damaged DNA duplexes

    Czech Academy of Sciences Publication Activity Database

    Šebera, Jakub; Humpolíčková, Jana; Hof, Martin; Kratochvílová, Irena; Páv, Ondřej; Rosenberg, Ivan; Nencka, Radim; Tanaka, Y.; Sychrovský, Vladimír

    Nagybörzsöny : -, 2014. [CESTC 2014. Central European Symposium on Theoretical Chemistry. 21.09.2014-25.09.2014, Nagybörzsöny] R&D Projects: GA ČR GA13-27676S Institutional support: RVO:61388963 ; RVO:61388955 ; RVO:68378271 Keywords : charge transfer * 8-oxoguanine * fluorescence spectroscopy Subject RIV: CF - Physical ; Theoretical Chemistry

  3. Miniaturized high-resolution mass/charge spectrograph /design study/

    Science.gov (United States)

    Taylor, L. H.

    1969-01-01

    Use of a double-focusing mass/charge spectrograph weighing less than 25 pounds is feasible for solar wind experiments. Instrument has a parallel-plate energy filter between the ion source and the double focusing units which alleviates the problem of designing an ion source of small energy spread.

  4. Study of the liquid water luminescence induced by charged particles

    International Nuclear Information System (INIS)

    Many observations suggested that liquid water (with impurities) could give a luminescence output when irradiated with charged particles. We investigate theoretical and practical possibility of detecting such luminescence. Preliminary results on this possibility are presented, and a layout of the device proposed for measuring luminescence is given. (authors)

  5. Listening to Children: Exploring Intuitive Strategies and Interactive Methods in a Study of Children's Special Places

    Science.gov (United States)

    Green, Carie

    2012-01-01

    Stemming from the UNCRC, childhood researchers have proposed a variety of methodological strategies for upholding children's rights and understanding their perspectives. This paper aims to advance the conversation on engaging children's perspectives by presenting data collection methods used in a qualitative study exploring children's special…

  6. Studies in Visual Perception and Reading in Disadvantaged Children.

    Science.gov (United States)

    Cohen, S. Alan

    Two studies were carried out to measure the difficulties in visual perception which affect the reading abilities of disadvantaged children. The first study involved children in the first grades of eight poverty-area schools. Results reinforced earlier findings that urban disadvantaged children scored poorly on tests of visual perception.…

  7. Enuresis: Epidemiological study in Moroccan children

    International Nuclear Information System (INIS)

    Enuresis is a common symptom that leads to significant psychosocialsequalae. In this study we analyzed three surveys in three different urbanand suburban regions in Morocco in order to evaluate the epidemiologicalcharacteristics and profiles of the young patients who had enuresis and theattitudes of their parents towards this problem. There were 1520 children andadolescents in this analysis whose age ranged between 5 and 15 years. Theywere attending various outpatient surgical and medical clinics when theirparents were asked to answer a pre-prepared questionnaire. The prevalence ofenuresis was 35% with preponderance of males (54%). The cause could not bedefined (primary) in 91.5% of the patients with enuresis. There were familialfactors associated with enuresis that included history of enuresis in theparents or siblings in 56% of the cases and coercion attitude of the parentsin 23%. Enuresis was associated with impediment of learning in 23%andchastisement of children in 85.4% of the cases. Twenty-three percent ofpatients also had chronic disorders. The parents were concerned mostly whenthe children approached puberty or when enuresis was secondary to anotherproblem. Spontaneous improvement was the rule by adolescence, hence only 8.7%sought medical advice for enuresis. Treatment was conventional in 67% of thecases and confined to restriction of fluids and food items in 73% of thetreated patients. We conclude that enuresis is apparently higher in Moroccanchildren compared to reports in other countries. However, enuresis was notconsidered a major medical problem of concern to parents who rarely soughtmedical advice for it. (author)

  8. Melanocytic nevi in children: A clinical study

    Directory of Open Access Journals (Sweden)

    Senthilkumar M

    2006-01-01

    Full Text Available BACKGROUND: Melanocytic nevi show different presentations in children which have not much studied in India. PURPOSES: To document the incidence and pattern of melanocytic nevi in children. METHODS: A total of 4,256 paediatric cases attending the dermatology OPD, JIPMER during the study period from August 2002 to August 2004 were screened for melanocytic nevi. FINDINGS: Out of these, 41 (0.96% cases were found to have melanocytic nevi. The mean age of these cases was 1.4 years (range of 3 days to 14 years. Fourteen (34.1% of them were males and 27 (65.9% were females with male to female ratio of 1:1.9. Majority of these cases (32 cases, 78% were in the age group of 0-1 year. Thirty-seven (90.2% cases had single lesion and 4 (9.8% cases had multiple lesions. The size of the nevi varied from 1.5 cm to 20 cm in 40 (97.6% cases and more than 20 cm in 1 (2.4% case. The most common site of involvement was the back (32 cases, 78% followed by head and neck (6 cases, 14.6%. Out of the total of 41 cases, 30 (73.2% were Mongolian spots, 8 (19.5% were congenital melanocytic nevi, one case (2.4% each had giant congenital melanocytic nevus, nevus spilus and nevus of Ota. Four cases had other associated cutaneous disorders. These included ashleaf macules in 2 cases, epidermolysis bullosa simplex in 1 case and a solitary case had both cafι-au-lait macule and mixed hemangioma. The systemic associations included seizures (suspected neurocutaneous melanosis in a solitary case of congenital melanocytic nevi. CONCLUSIONS: The spectrum of melanocytic nevi seen in children in this study partially differs from this of abroad studies. LIMITATION: Unicentre hospital-based study which cannot be generalized.

  9. Study of Charge Carrier Transport in GaN Sensors

    Directory of Open Access Journals (Sweden)

    Eugenijus Gaubas

    2016-04-01

    Full Text Available Capacitor and Schottky diode sensors were fabricated on GaN material grown by hydride vapor phase epitaxy and metal-organic chemical vapor deposition techniques using plasma etching and metal deposition. The operational characteristics of these devices have been investigated by profiling current transients and by comparing the experimental regimes of the perpendicular and parallel injection of excess carrier domains. Profiling of the carrier injection location allows for the separation of the bipolar and the monopolar charge drift components. Carrier mobility values attributed to the hydride vapor phase epitaxy (HVPE GaN material have been estimated as μe = 1000 ± 200 cm2/Vs for electrons, and μh = 400 ± 80 cm2/Vs for holes, respectively. Current transients under injection of the localized and bulk packets of excess carriers have been examined in order to determine the surface charge formation and polarization effects.

  10. ELECTROCHEMICAL STUDIES OF MOBILE CHARGED SPECIES DURING ZIRCONIUM ALLOY OXIDATION

    OpenAIRE

    Smith, James Stephen

    2013-01-01

    This research has used a suite of electrochemical techniques, both in-situ and ex-situ to investigate the mobile charged species in the oxides of zirconium alloys. Limits on the corrosion resistance of existing zirconium alloys used for fuel cladding are a major restriction on the burn-up that can be achieved within a pressurised water reactor (PWR). Developing a full mechanistic understanding of the corrosion process of zirconium alloys in the primary water environment is necessary for prolo...

  11. Systematic study of free monopolar discharge in dielectrics with charge excess

    International Nuclear Information System (INIS)

    The monopolar space charge motion in dielectrics is studied in the aim of providing general information about it to the experimentalist. The electric current is obtained for many initial charge distributions and some relations are derived linking the behavior of the current to the initial charge distribution. Methods are proposed for obtaining the mobility of the carriers from experimental results. Finally the conditions for observation of current reversals are analysed. (Author)

  12. A series resonant switching charging circuit for kicker modulator and its simulation study

    International Nuclear Information System (INIS)

    A novel high voltage charging circuit specially designed for the prototype kicker modulator of the Hefei Light Source storage ring was presented. Zero-current series resonant switching techniques and a simple charging voltage control scheme was adopted in the circuit. Simulation model was established to study the performance of the circuit with a high voltage capacitor load. Designed charging voltage stability and repetition rate can be achieved through simulation analysis. Methods to increase the repetition rate are discussed

  13. QIE: Performance Studies of the Next Generation Charge Integrator

    Energy Technology Data Exchange (ETDEWEB)

    Roy, T. [Florida Inst. Tech.; Yumiceva, F. [Florida Inst. Tech.; Hirschauer, J. [Fermilab; Freeman, J. [Fermilab; Hughes, E. [Rutgers U., Piscataway; Hare, D. [Fermilab; Dal Monte, L. [Fermilab; Whitbeck, A. [Fermilab; Zimmerman, T. [Fermilab

    2015-02-06

    The Phase 1 upgrade of the Hadron Calorimeter (HCAL) in the Compact Muon Solenoid (CMS) detector at the Large Hadron Collider (LHC) will include two new generations (named QIE10 and QIE11) of the radiation-tolerant flash ADC chip known as the Charge Integrator and Encoder or QIE. The QIE integrates charge from a photo sensor over a 25 ns time period and encodes the result in a non-linear digital output while having a good sensitivity in both the higher and the lower energy values. The charge integrator has the advantage of analyzing fast signals coming from the calorimeters as long as the timing and pulse information is available. The calorimeters send fast, negative polarity signals, which the QIE integrates in its non-inverting input amplifier. The input analog signal enters the QIE chip through two points: signal and reference. The chip integrates the difference between these two values. This helps in getting rid of the incoming noise, which is effectively cancelled out in the difference. Over a period of about six months between September, 2013 and April, 2014 about 320 QIE10 and about 20 QIE11 chips were tested in Fermilab using a single-chip test stand where every individual chip was tested for its characteristic features using a clam-shell. The results of those tests performed on the QIE10 and QIE11 are summarized in this document.

  14. QIE: performance studies of the next generation charge integrator

    International Nuclear Information System (INIS)

    The Phase 1 upgrade of the Hadron Calorimeter (HCAL) in the Compact Muon Solenoid (CMS) detector at the Large Hadron Collider (LHC) will include two new generations (named QIE10 and QIE11) of the radiation-tolerant flash ADC chip known as the Charge Integrator and Encoder or QIE. The QIE integrates charge from a photo sensor over a 25 ns time period and encodes the result in a non-linear digital output while having a good sensitivity in both the higher and the lower energy values. The charge integrator has the advantage of analyzing fast signals coming from the calorimeters as long as the timing and pulse information is available. The calorimeters send fast, negative polarity signals, which the QIE integrates in its non-inverting input amplifier. The input analog signal enters the QIE chip through two points: signal and reference. The chip integrates the difference between these two values. This helps in getting rid of the incoming noise, which is effectively cancelled out in the difference. Over a period of about six months between September, 2013 and April, 2014 about 320 QIE10 and about 20 QIE11 chips were tested in Fermilab using a single-chip test stand where every individual chip was tested for its characteristic features using a clam-shell. The results of those tests performed on the QIE10 and QIE11 are summarized in this document

  15. Do autistic children have higher levels of caries? A cross-sectional study in Turkish children

    Directory of Open Access Journals (Sweden)

    Namal Necmi

    2007-06-01

    Full Text Available The aim of this study is to assess whether the dental caries experience is higher in children with an autistic disorder (AD than in normal children. Three schools for autistic children and three standard elementary schools in Istanbul, Turkey, were included in a cross-sectional study. Subjects were orally examined. Socio-demographic information and data about their oral care habits were obtained from their parents from records. Sixty-two children with AD and 301 children without AD were examined. Their ages varied between 6 and 12 years. Children with AD compared to those without AD had lower experience of caries. Logistic regression analysis of DMFT showed that the dental status was positively affected in younger children (OR = 15.57; 95% CI 7.62, 31.80, children from families with high income (OR = 5.42; 95% CI 2.31, 12.75, children brushing teeth regularly (OR = 2.01, 95% CI 1.10, 3.68, children consuming less sugar (OR = 5.01; 95% CI 2.57, 9.76 and in those with AD (OR=3.99; 95% CI 1.56, 10.19. Children with AD had better caries status than children without AD at younger ages.

  16. Microbeam Studies of Diffusion Time Resolved Ion Beam Induced Charge Collection from Stripe-Like Junctions

    International Nuclear Information System (INIS)

    To design more radiation tolerant Integrated Circuits (ICs), it is essential to create and test accurate models of ionizing radiation induced charge collection dynamics within microcircuits. A new technique, Diffusion Time Resolved Ion Beam Induced Charge Collection (DTRIBICC), is proposed to measure the average arrival time of the diffused charge at the junction. Specially designed stripe-like junctions were experimentally studied using a 12 MeV carbon microbeam with a spot size of 1 microm. The relative arrival time of ion-generated charge is measured along with the charge collection using a multiple parameter data acquisition system. The results show the importance of the diffused charge collection by junctions, which is especially significant in accounting for Multiple Bit Upset (MBUs) in digital devices

  17. Electrophoretic mobility of a charged colloidal particle: a computer simulation study

    International Nuclear Information System (INIS)

    We study the mobility of a charged colloidal particle in a constant homogeneous electric field by means of computer simulations. The simulation method combines a lattice Boltzmann scheme for the fluid with standard Langevin dynamics for the colloidal particle, which is built up from a net of bonded particles forming the surface of the colloid. The coupling between the two subsystems is introduced via friction forces. In addition, explicit counterions, also coupled to the fluid, are present. We observe a non-monotonic dependence of the electrophoretic mobility on the bare colloidal charge. At low surface charge density we observe a linear increase of the mobility with bare charge, whereas at higher charges, where more than half of the ions are co-moving with the colloid, the mobility decreases with increasing bare charge

  18. Phthalate concentrations in house dust in relation to autism spectrum disorder and developmental delay in the CHildhood Autism Risks from Genetics and the Environment (CHARGE) study

    OpenAIRE

    Philippat, Claire; Bennett, Deborah H.; Krakowiak, Paula; Rose, Melissa; Hwang, Hyun-Min; Hertz-Picciotto, Irva

    2015-01-01

    Background Phthalates are endocrine-disrupting chemicals that influence thyroid hormones and sex steroids, both critical for brain development. Aim We studied phthalate concentrations in house dust in relation to the risks of developing autism spectrum disorder (ASD) or developmental delay (DD). Methods Participants were a subset of children from the CHARGE (CHildhood Autism Risks from Genetics and the Environment) case–control study. ASD and DD cases were identified through the California De...

  19. Psychological and Educational Studies with Spina Bifida Children. Final Report.

    Science.gov (United States)

    Diller, Leonard; And Others

    To measure school achievements in spina bifida children, to relate these measures to certain variables, to obtain information on educational problems, and to study facets of cognition and its changes with age, 77 spina bifida children and 53 amputees (all aged 5 to 15) were tested. Sixty non-disabled children were at times used for controls. The…

  20. Observational cohort study of HIV-infected African children.

    NARCIS (Netherlands)

    Laufer, M.K.; Oosterhout, J.J. van; Perez, M.A.; Kanyanganlika, J.; Taylor, T.E.; Plowe, C.V.; Graham, S.M.

    2006-01-01

    BACKGROUND: Most information about children living with HIV is based on follow up from children identified through mother-to-child transmission studies. Children identified through voluntary counseling and testing (VCT) represent a unique cohort that has not been previously described in the literatu

  1. The preliminary study on saturation problem of charge sensitive preamplifier

    International Nuclear Information System (INIS)

    The problem of a CSA (Charge Sensitive Preamplifier) saturation is an important problem .In the paper, starting from the working principle of a CSA, through the analysis of the detector output equivalent pulse sequence characteristics, combined with the actual physical process of a CSA, the upper limit value of CSA is conduced. And at the same time, the relationship between the count rates Ni and the time constant times i and the results of numerical analysis are given, as well as providing the theory basis for the design of a CSA considering the saturation limit. (authors)

  2. Study on biogas premixed charge diesel dual fuelled engine

    International Nuclear Information System (INIS)

    This paper presents an experimental investigation of a small IDI biogas premixed charge diesel dual fuelled CI engine used in agricultural applications. Engine performance, diesel fuel substitution, energy consumption and long term use have been concerned. The attained results show that biogas-diesel dual fuelling of this engine revealed almost no deterioration in engine performance but lower energy conversion efficiency which was offset by the reduced fuel cost of biogas over diesel. The long term use of this engine with biogas-diesel dual fuelling is feasible with some considerations

  3. Transnational migration and the study of children: an introduction

    OpenAIRE

    Gardner, Katy

    2012-01-01

    This introductory article sets out the main challenges that the study of children poses for the understanding of transnational migration. Children are not simply a neglected empirical group, whose perspectives are rarely considered; children can also provide researchers with important insights concerning the nature of transnationalism if the phenomenon is considered through their eyes. Research on transnational children brings to the fore issues concerning familial practices and discourses, t...

  4. Positron annihilation studies of some charge transfer molecular complexes

    CERN Document Server

    El-Sayed, A; Boraei, A A A

    2000-01-01

    Positron annihilation lifetimes were measured for some solid charge transfer (CT) molecular complexes of quinoline compounds (2,6-dimethylquinoline, 6-methoxyquinoline, quinoline, 6-methylquinoline, 3-bromoquinoline and 2-chloro-4-methylquinoline) as electron donor and picric acid as an electron acceptor. The infrared spectra (IR) of the solid complexes clearly indicated the formation of the hydrogen-bonding CT-complexes. The annihilation spectra were analyzed into two lifetime components using PATFIT program. The values of the average and bulk lifetimes divide the complexes into two groups according to the non-bonding ionization potential of the donor (electron donating power) and the molecular weight of the complexes. Also, it is found that the ionization potential of the donors and molecular weight of the complexes have a conspicuous effect on the average and bulk lifetime values. The bulk lifetime values of the complexes are consistent with the formation of stable hydrogen-bonding CT-complexes as inferred...

  5. Children and Clinical Studies: Why Clinical Studies Are Important

    Medline Plus

    Full Text Available ... children's health with the goal to develop treatments, drugs, and devices specific to children. Resources for a Wide Range of Audiences The Children and Clinical ... and Postcards ...

  6. Children's Digital Practices: Case Studies of Children Viewing and Representing with Digital Text

    Science.gov (United States)

    Churchill, Daniel; Khoo, Kay Yong

    2012-01-01

    This paper reports on case studies of four primary school children and their digital practices in Hong Kong. The study explored how the participating children view and represent through digital text in the context of their out-of-school technology use. Understanding how these practices extended into their English language classrooms was explicated…

  7. TRACHEOSTOMY IN CHILDREN: A CLINICAL STUDY

    Directory of Open Access Journals (Sweden)

    Shankar

    2015-11-01

    Full Text Available : A trachestomy is a small, surgical opening from the skin to the anterior wall of the trachea, pediatric patients for whom tracheostomy is more hazardous than adults, consideration have different anatomy, medical conditions, and prognoses than adults, even the tracheostomy tubes are different in size, the indications for tracheostomy in children include, bypassing airway obstruction (Laryngo- tracheobronchitis, epiglottitis, providing access for prolong ventilation, and facilitating tracheo-bronchial toilet, to day prime indication for pediatrics tracheostomy is subglottic stenosis. We have reviewed experience with 84 tracheostomies under 13 years of age in our hospital. We are here discussing the common indications and complications, difficulty in decannulation in pediatric patients, in our study the common indication is the foreign body bronchus followed by other conditions.

  8. Economic Viability Study of an On-Road Wireless Charging System with a Generic Driving Range Estimation Method

    OpenAIRE

    Aditya Shekhar; Venugopal Prasanth; Pavol Bauer; Mark Bolech

    2016-01-01

    The economic viability of on-road wireless charging of electric vehicles (EVs) strongly depends on the choice of the inductive power transfer (IPT) system configuration (static or dynamic charging), charging power level and the percentage of road coverage of dynamic charging. In this paper, a case study is carried out to determine the expected investment costs involved in installing the on-road charging infrastructure for an electric bus fleet. Firstly, a generic methodology is described to d...

  9. Study of charge reader probes for electret dosemeters

    International Nuclear Information System (INIS)

    Electrets are insulating materials with a quasi-permanent polarization. It can be made from carnauba wax, Teflon and other materials for several applications as transducers, electrophotography, high efficiency air filters and as radiation dosimeters. Electret dosemeters may be used for α, β, γ, X, e- and neutrons radiations with a low construction cost and a simple associated instrumentation. The probe, for charge measurements of the electret dosimeters, is an important device in the experimental set up and its geometry varies according to the geometry of the dosimeter or the scope of the measurements. In this work the development of several probes is described (cylindrical, 1/3 cylindrical and three points probes with different sizes). From the measurements one can demonstrate that cylindrical probe may be used for cylindrical electret geometry, 1/3 cylindrical probe for measurements of directional dependence of the dose and point probe for scanning measurements of plane areas. For high resolution, small point probe may be used and for high sensitivity, the probe-electret distance must be minimized taking account of the Paschen discharge. (author)

  10. Electrical resistivity study of some organic charge transfer complexes under pressure

    International Nuclear Information System (INIS)

    Electrical resistivity study of the organic charge transfer complexes tetramethyl benzidine - TCNQ and tetramethyl p-phenylene diamine - TCNQ has been carried out up to pressure 80 kilobar. Using the structural aspect, a conduction mechanism under pressure is suggested. (author)

  11. Vitamin D and tuberculosis: a multicenter study in children

    OpenAIRE

    Venturini, Elisabetta; Facchini, Ludovica; Martinez-Alier, Nuria; Novelli, Vas; Galli, Luisa; Martino, Maurizio; Chiappini, Elena

    2014-01-01

    Background The aim of this study is to evaluate vitamin D levels in children with latent and active TB compared to healthy controls of the same age and ethnical background. Methods A multicenter observational study has been conducted in three tertiary care paediatric centres: Anna Meyer Children's University Hospital, Florence, Italy; Evelina London Children's Hospital, London, United Kingdom and Great Ormond Street Hospital, London, United Kingdom. Vitamin D was considered deficient if the s...

  12. Gait maturation in children with cerebral palsy: A pilot study

    OpenAIRE

    J.S. Marques; P. Roquetti Fernandes; J. Fernandes Filho; F. B. Policarpo

    2011-01-01

    This study aimed at observing children with cerebral palsy's (CP) gait maturation and to correlate gait maturation's motor skill parameters. Podogram and video shooting of eight children's gait were used. Children up to seven years of age participated in the study. Cluster analysis was applied, dividing the sample into two groups, using the relation between pelvis’ width and the spreading of the ankles (REL) as parameters. Data were analyzed using t-test, analysis of Deltas, and Pearson’s cor...

  13. A Charge Separation Study to Enable the Design of a Complete Muon Cooling Channel

    Energy Technology Data Exchange (ETDEWEB)

    Yoshikawa, C. [Muons, Inc.; Ankenbrandt, Charles M. [Muons, Inc.; Johnson, Rolland P. [Muons, Inc.; Derbenev, Yaroslav [JLAB; Morozov, Vasiliy [JLAB; Neuffer, David [FNAL; Yonehara, K. [FNAL

    2013-12-01

    The most promising designs for 6D muon cooling channels operate on a specific sign of electric charge. In particular, the Helical Cooling Channel (HCC) and Rectilinear RFOFO designs are the leading candidates to become the baseline 6D cooling channel in the Muon Accelerator Program (MAP). Time constraints prevented the design of a realistic charge separator, so a simplified study was performed to emulate the effects of charge separation on muons exiting the front end of a muon collider. The output of the study provides particle distributions that the competing designs will use as input into their cooling channels. We report here on the study of the charge separator that created the simulated particles.

  14. STUDY OF OVARIAN LESIONS IN CHILDREN

    Directory of Open Access Journals (Sweden)

    Nagarjuna

    2015-11-01

    Full Text Available : AIM: To study ovarian lesions in paediatric patients. MATERIALS AND METHODS: All cases of ovarian lesions presenting to Niloufer Hospital during the study period spanning 7 years were included in the study. All cases were clinically examined and evaluated with serum markers like α-fetoprotein and β-HCG, ultrasonography of abdomen and pelvis and contrast enhanced computed tomography of abdomen and pelvis. The cases were managed either conservatively or surgically depending on the diagnosis. RESULTS: A total of 36 cases of ovarian lesions presented to Niloufer Hospital during the study period. The age of the patients ranged from newborn to 14 years. The most common presenting symptom was an abdominal or pelvic mass. The most common ultrasound character of the non-neoplastic ovarian lesion was cystic whereas that of a neoplastic ovarian lesion was complex or mixed. Non neoplastic lesions were present in 22 patients. Neoplastic lesions were seen in 14 patients. CONCLUSION: Physiological or functional ovarian cysts are the commonest ovarian lesions seen in the paediatric age group. Ultrasonogram is accurate and very reliable in distinguishing neoplastic from non-neoplastic and malignant from benign ovarian lesions. Non-neoplastic lesions can be managed conservatively in about 40% of cases. Neoplastic lesions in children require a less radical approach in order to preserve ovarian function.

  15. Intraocular Pressure and Associations in Children. The Gobi Desert Children Eye Study

    OpenAIRE

    Yang, Da Yong; Guo, Kai; Wang, Yan; Guo, Yuan Yuan; Yang, Xian Rong; Jing, Xin Xia; Guo, Hai Ke; Tao, Yong; Zhu, Dan; Jonas, Jost B.

    2014-01-01

    Purpose To assess the intraocular pressure (IOP) and its association in children in a population living in an oasis in the Gobi Desert. Methods The cross-sectional school-based study included all schools in the Ejina region. The children underwent an ophthalmic examination, non-contact tonometry and measurement of blood pressure and body height and weight. Results Out of eligible 1911 children, 1565 (81.9%) children with a mean age of 11.9±3.5 years (range: 6–21 years) participated. Mean sphe...

  16. Small angle neutron scattering study of mixed micelles of oppositely charged surfactants

    Indian Academy of Sciences (India)

    J V Joshi; V K Aswal; P S Goyal

    2008-11-01

    Structures of mixed micelles of oppositely charged surfactants dodecyltrimethylammonium bromide (DTAB) and sodium dodecyl sulphate (SDS) have been studied using small angle neutron scattering. The concentration of one of the components was kept fixed (0.3 M) and that of another varied in the range 0 to 0.1 M. The aggregation number and micellar size increase and fractional charge decreases dramatically with the addition of small amount of oppositely charged surfactant. The effect of addition of SDS on DTAB is significantly different from that of the addition of DTAB on SDS. The contrast variation SANS experiments using deuterated surfactant suggests the homogeneous mixing of two components in mixed micellar system.

  17. X-ray diffraction studies of charge density waves in cuprate superconductors: A brief review

    International Nuclear Information System (INIS)

    High temperature superconductivity in the cuprates has fascinated scientists for more than 25 years, but there is still no consensus on the pairing mechanism. Soon after the discovery of high temperature superconductivity, it was suggested that the cuprates have an incipient tendency towards spatial electronic order – spin and charge order. In this paper, I will review X-ray diffraction studies of charge density waves in the cuprates. These results, by a number of different groups, indicate that short-range charge correlations exist across the cuprate family, and in many cases are clearly competing with the superconductivity

  18. Study of a lithium-ion battery charge-discharge test unit characteristics*

    Science.gov (United States)

    Kopylov, E. A.; Mizrah, E. A.; Fedchenko, A. S.; Lobanov, D. K.

    2016-04-01

    The article describes the structure of a charge-discharge unit which allows to perform electrical, resource and thermal testing of several lithium-ion batteries simultaneously. The principle of operation of a one battery research channel (BRC) is shown. This study evaluated the stabilization error and rate of change of charge/discharge currents, the switching time from the charge mode to the discharge mode and vice versa for a single BRC and parallel BRCs. The possibility of increasing the maximum battery testing current due to the parallel connection of multiple BRCs without using a current alignment device between channels was discussed.

  19. Children's Questions: A Study of Questions Children Ask While Learning to Use a Computer.

    Science.gov (United States)

    Shaw, Donna Gail; And Others

    1985-01-01

    Describes a study conducted at a Texas elementary school which examined the types of questions second-grade children ask as they are taught to use microcomputers. A classification of questions into eight categories indicates children asked most about keyboard, data entry, and meaning of program instructions. (MBR)

  20. Electron Charge Density Distribution from X-Ray Diffraction Study of the 4-Methoxybenzenecarbothioamide Compound

    Directory of Open Access Journals (Sweden)

    Mokhtaria Drissi

    2013-01-01

    Full Text Available The molecular electron charge density distribution of the title compound is described accurately using the multipolar model of Hansen and Coppens. The net atomic charge and the in-crystal molecular dipole moment have been determined in order to understand the nature of inter- and intramolecular charge transfer. The study reveals the nature of intermolecular interactions including charge transfer and hydrogen bonds in the title compound. In this crystal, the molecules form dimers via N–HS intermolecular hydrogen bonds. The dimers are further linked by C–HO hydrogen bonds into chains along the c crystallographic axis. This study has also allowed us to determine the electrostatic potential and therefore locate the electropositive part and the electronegative part in molecular scale of the title compound.

  1. Children's advertising exposure and materialistic orientations: A longitudinal study

    NARCIS (Netherlands)

    Opree, S.J.; Valkenburg, P.M.; Reijmersdal, E.A. van; Buijzen, M.A.

    2012-01-01

    As many as nine out of 10 parents worry that children's frequent exposure to advertising makes them materialistic. In this study we not only aim to investigate if children's advertising exposure indeed affects their materialism, but also how it affects their materialism (i.e., by studying the mediat

  2. Forces exerted by jumping children: A pilot study

    NARCIS (Netherlands)

    Moes, C.C.M.; Bakker, H.E.

    1998-01-01

    This article reports on a pilot study of the loads exerted vertically by children when jumping. The subjects of the study were 17 children, aged from two to twelve years. Measurements were made using video recordings and a force-plate. The influence of the stiffness of the base and of jumping with a

  3. Preliminary study for the detection of neutrons in heavy-ion collisions with charged particle detectors

    OpenAIRE

    Auditore L.; Pagano A.; Russotto P.

    2015-01-01

    At Laboratori Nazionali del Sud (LNS) the CHIMERA 4π multidetector has been designed and setup to detect charged particles emitted in heavy ion collisions at intermediate energies. Properties and performances of CHIMERA have been widely demonstrated by published results obtained in the performed experiments. Moreover, in recent years, a new charged particle detector (ChPD) for correlation studies (FARCOS) has been designed, and recently a first prototype has been coupled to CHIMERA, in order ...

  4. Adoption of Children With Disabilities: A Study With Adoptive Parents

    OpenAIRE

    Gisele De Mozzi; Adriano Henrique Nuernberg

    2016-01-01

    Abstract Taking into consideration the supremacy of a child's profile often chosen by adoptive parents, this study aimed to understand the adoption of children with disabilities from the perspective of adoptive parents who have experienced this practice. The participants were eleven adoptive families of disabled children, all of whom had knowledge about the health conditions of the adoptive children at the time of adoption. The instruments used were a semi-structured interview and a sociodemo...

  5. Epilepsy in Children With ADHD: A Population-Based Study

    OpenAIRE

    Davis, Shanlee M.; Katusic, Slavica K.; Barbaresi, William J.; Killian, Jill; Weaver, Amy L.; Ottman, Ruth; Wirrell, Elaine C.

    2010-01-01

    Prior studies suggest a higher incidence of symptoms of attention-deficit/hyperactivity disorder in children with epilepsy, but few have investigated epilepsy in children with attention-deficit/hyperactivity disorder. Our objective was to compare the incidence and characteristics of epilepsy among population-based, research identified cohorts of children with (N=358) and without attention-deficit/hyperactivity disorder (N=728), based on medical record review to age 20. Data abstracted include...

  6. Study on tobacco use and awareness among marginalized children

    OpenAIRE

    Raval, S.; S Maudgal; More, N.

    2010-01-01

    Background : The current study entailed a survey of children from the lower socioeconomic strata of rural and urban regions of the states of Maharashtra and Assam who are vulnerable to tobacco usage. More than 1700 children were checked for precancerous lesions and 1004 were surveyed for tobacco habits and awareness. Aims: The objective of the survey was to determine and report on all the variant factors affecting the use of tobacco among the underprivileged children population. The aim of t...

  7. A study of food buying behavior among Chinese children

    OpenAIRE

    Fan, Y.; Li, Y.

    2009-01-01

    The paper reports a study on food buying behaviour among Chinese children aged between 10-13 years old. There are two important findings. Firstly, the growing influence of commercial environment. During the learning of consumer behaviour by Chinese children, the parental role of guidance remains prominent, and their recommendations have a decisive impact on children’s food choices. Secondly, the perceived importance of product attributes. Chinese children tend to pay more attention to nutr...

  8. Interpreting writing of children with intellectual disabilities: A comparative study.

    OpenAIRE

    Vieira de Figueiredo, R.

    2007-01-01

    This article reports the results of developmental test analyses on literacy conducted with children with intellectual disabilities in Quebec and Brazil. Grounded on studies carried out in Argentina by Ferreiro and Teberosky (1986), with children without intellectual disabilities, we deal, comparatively, with three aspects in the development of literacy in children with intellectual disabilities: their interpretation of fragments of writing, the connection they establish between letters and nu...

  9. Lithium-ion batteries: Evaluation study of different charging methodologies based on aging process

    International Nuclear Information System (INIS)

    Highlights: • Different charging methodologies have been tested and analyzed. • Battery impedance representation using the Randle’s equivalent circuit. • Investigate the impact of the charging methodology on the battery’s lifetime. • An extended analysis to select the proper charging method that can be used to design an enhanced charging system. - Abstract: In this paper, high power 7 A h LiFePO4-based cells (LFP) have been used to investigate the impact of the charging methodology on the battery’s lifetime. Three charging techniques have been used: Constant Current (CC), Constant Current–Constant Voltage (CC–CV) and Constant Current–Constant Voltage with Negative Pulse (CC–CVNP). A comparative study between these techniques is presented in this research. For this purpose, a characterization of the batteries has been performed using capacity test and electrochemical impedance spectroscopy (EIS). As expected the obtained results showed that the battery’s aging rate depends on the charging methodology. Indeed, it has been shown that a combination of low amplitude and fewest number of negative pulses has a positive effect on battery’s capacity fading. From the impedance measurements, the results have demonstrated that the CC–CVNP technique with low amplitude and fewest number of negative pulses is more effective than the other techniques in reducing the concentration polarization resistance and the diffusion time constant. This research has provided an extended analysis to select the proper charging methodology that can be used to design an enhanced charging system

  10. Study of neutralization kinetics in charged polymer-metal nanocomposite systems by photoemission spectroscopy

    International Nuclear Information System (INIS)

    In case of photoelectron spectroscopy of an insulating material the data obtained from the charged surface are often distorted due to differentially charged surface domains. Recently we have developed a controlled surface neutralization technique to study the kinetics of the surface charging. Here we demonstrate the application of the technique to study the neutralization kinetics of both thick and thin films of charged polymer-metal nanocomposite material using photoemission. Neutralization kinetics of grounded and floated pure polymer thin films was also studied. It was observed that for the thick sample the transition of positively charged domains to overcompensated ones occurs through percolation. In case of grounded thin films the growth of overcompensated domains exhibit a linear behavior followed by saturation. When electrons appear at both surfaces of a floated thin film, the neutralization kinetics show a completely different behavior. Present investigation indicates that for thin films of insulating materials appearing to be neutral in presence of an electron source, controlled neutralization technique may be an important tool to distinguish between presence of multiple chemical species and differential charging.

  11. Onychomycosis and Children – A Multicenter Study

    OpenAIRE

    Zisova L.; Chokoeva A.; Sotiriou E.; Valtchev V.; Gospodinov D.

    2015-01-01

    Onychomycosis is a chronic disease caused by dermatophytes, yeasts and molds, which leads to destruction of the nail plate of the fingernails and toenails. The incidence of onychomycosis in children is considerably smaller compared with that in adults. Onychomycosis in children under 6 years of age is particularly unusual. The trauma and the hyperhidrosis after puberty are the major predisposing factor for fungal nail infection in childhood. Some systemic diseases and congenital syndromes hav...

  12. The study comparing parenting style of children with ADHD and normal children

    Directory of Open Access Journals (Sweden)

    Moghaddam, Mahboobeh Firouzkouhi

    2013-12-01

    Full Text Available Aim. Attention deficit-hyperactivity disorder is one of the most often diagnosed psychiatric disorders in children and adolescents based on hyperactivity, attention deficit and impulsivity criteria. This disorder causes a lot of problems at home, school and social situations. Considering the family and parenting factors in growth and development of ADHD children, the parenting interventions are consider as a primary intervention programs for this children. Parenting management training, based on social learning models, is an effective and practical way for treatment of children with incongruent behavior. In this study, we evaluate parenting styles of ADHD children and normal children. Methods. This study was conducted in Zahedan in 2012. Subjects aged 7 to 12. They were divided into patient and normal groups. Parenting styles were evaluated with Baumrind’s questionnaire. The data were analyzed with SPSS ver.18. Results. The findings showed that the parents of ADHD children have lower permissive score than the normal group, but authoritarian score was lower in the normal group. The authoritative score has no significant difference between the two groups. In addition, age, gender, and parent’s education affected the parenting styles. Discussion. The present study indicates that parents with ADHD children have different parenting styles; and factors like gender and parents education are influential in parenting methods. This finding were also present in some past surveys. Many studies have shown that teaching-parenting styles to parents with ADHD children improves the inner family relationship. Conclusion . The results indicated that parents of children with ADHD are less permissive but more authoritarian in their parenting.

  13. Charge state distribution studies of the metal vapor vacuum arc ion source

    International Nuclear Information System (INIS)

    We have studied the charge state distribution of the ion beam produced by the MEVVA (metal vapor vacuum arc) high current metal ion source. Beams produced from a wide range of cathode materials have been examined and the charge state distributions have been measured as a function of many operational parameters. In this paper we review the charge state data we have accumulated, with particular emphasis on the time history of the distribution throughout the arc current pulse duration. We find that in general the spectra remain quite constant throughout most of the beam pulse, so long as the arc current is constant. There is an interesting early-time transient behavior when the arc is first initiated and the arc current is still rising, during which time the ion charge states produced are observed to be significantly higher than during the steady current region that follows. 12 refs., 5 figs

  14. Study of plasma charging-induced white pixel defect increase in CMOS active pixel sensor

    International Nuclear Information System (INIS)

    Plasma process-induced 'white pixel defect' (WPD) of CMOS active pixel sensor (APS) is studied for Si3N4 spacer etch back process by using a magnetically enhanced reactive ion etching (MERIE) system. WPD preferably takes place at the wafer edge region when the magnetized plasma is applied to Si3N4 etch. Plasma charging analysis reveals that the plasma charge-up characteristic is well matching the edge-intensive WPD generation, rather than the UV radiation. Plasma charging on APS transfer gate might lead to a gate leakage, which could play a role in generation of signal noise or WPD. In this article the WPD generation mechanism will be discussed from plasma charging point of view

  15. A cryogenic target to study charge nonsymmetric muonic molecules

    International Nuclear Information System (INIS)

    An experimental setup, including a cryogenic gas target with temperature control and gas filling systems, has been developed to study muon catalyzed fusion in gas mixtures of hydrogen and helium isotopes

  16. Peer Group Status of Gender Dysphoric Children: A Sociometric Study

    OpenAIRE

    Wallien, Madeleine S. C.; Veenstra, Rene; Kreukels, Baudewijntje P. C.; Cohen-Kettenis, Peggy T.

    2010-01-01

    In this sociometric study, we aimed to investigate the social position of gender-referred children in a naturalistic environment. We used a peer nomination technique to examine their social position in the class and we specifically examined bullying and victimization of gender dysphoric children. A total of 28 children (14 boys and 14 girls), referred to a gender identity clinic, and their classmates (n = 495) were included (M age, 10.5 years). Results showed that the gender-referred children...

  17. A Comparative Study of the Spontaneous Social Interactions of Children with High-Functioning Autism and Children with Asperger's Disorder

    Science.gov (United States)

    Macintosh, Kathleen; Dissanayake, Cheryl

    2006-01-01

    A comparative observational study was undertaken of the spontaneous social interactions of children with high-functioning autism and Asperger's disorder. The sample comprised 20 children with high-functioning autism, 19 children with Asperger's disorder and 17 typically developing children matched on chronological age and overall mental age. A…

  18. Study on Magnesium based Pyrotechnic Composition as a Priming Charge

    OpenAIRE

    A.S. Redkar; V. A. Mujumdar; Singh, S. N.

    1996-01-01

    A new pyrotechnic composition containing Mg/KNO3/phenolic resin has been formulated and studied in detail for its sensitivity, mechanical and thermal properties, moisture and environmental effects and performance in a closed vessel. The data generated reveal that this composition shows superior performance, better mechanical properties and less susceptibility to moisture as compared to gunpowder. In addition, performance of the composition under extreme hot (45 degree centigrade) and c...

  19. Children's Family Drawings: A Study of Attachment, Personality, and Adjustment

    Science.gov (United States)

    Goldner, Limor; Scharf, Miri

    2011-01-01

    This study examined the relationship between children's attachment security, as manifested in their family drawings, and their personality and adjustment. Family drawings were collected from 222 Israeli children, as well as data regarding their personality and adjustment. Each drawing was coded and classified into 1 of 4 attachment categories…

  20. Peer Group Status of Gender Dysphoric Children : A Sociometric Study

    NARCIS (Netherlands)

    Wallien, Madeleine S. C.; Veenstra, Rene; Kreukels, Baudewijntje P. C.; Cohen-Kettenis, Peggy T.

    2010-01-01

    In this sociometric study, we aimed to investigate the social position of gender-referred children in a naturalistic environment. We used a peer nomination technique to examine their social position in the class and we specifically examined bullying and victimization of gender dysphoric children. A

  1. Improving Fine Motor Skills in Young Children: An Intervention Study

    Science.gov (United States)

    Brown, Carol G.

    2010-01-01

    The aim of this study was to evaluate the effect of the Primary Movement programme on the fine motor skills of children in an early years setting in an area of high social disadvantage. Primary Movement is a programme which can be used as an early intervention technique to help children inhibit persistent primary reflexes that have been shown to…

  2. Improving Children's Formal Word Definitions: A Feasibility Study

    Science.gov (United States)

    Marinellie, Sally A.

    2010-01-01

    The ability to define a word with accuracy and precision is an important skill that has been associated with academic achievement. This study investigated the feasibility of conducting a lesson on formal word definitions to improve children's definitional production. The participants were 18 children in grade 4 (mean age: 9 years; 8 months) who…

  3. Study Questions Use of Antidepressants for Children, Teens

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_159262.html Study Questions Use of Antidepressants for Children, Teens They ... interpersonal therapy -- as the first-line treatment," said study author Dr. Andrea Cipriani. He is an associate ...

  4. Study of charged current reactions induced by muon antineutrinos

    International Nuclear Information System (INIS)

    We present in this work a study of antineutrino reactions on light targets. We have used the Gargamelle cloud chamber with a propane-freon mix. In the 2 first chapters we give a brief description of the experimental setting and we present the selection criteria of the events. In the third chapter we analyse the data for the reaction anti-ν + p → μ+ + n that preserves strangeness. We have deduced the values of the axial (MA) and vector (MV) form factors: MA = (O.92 ± 0.08) GeV and MV = (0.86 ± 0.04) GeV. In the fourth chapter we study reactions in which strange particles appear (ΔS = 1) and we have determined their production cross-sections. The elastic reaction: anti-ν + p → μ+ + Λ is studied in a more accurate manner thanks to a 3-constraint adjustment that enables the selection of events occurring on free protons. We have deduced from our data the longitudinal, orthogonal and transverse polarization of Λ, we have got respectively Pl = -0.06 ± 0.44; Pp = 0.29 ± 0.41; Pt 1.05 ± 0.30. We have also deduced the values of the total cross-section as a function of the incident antineutrino energy E: σ (0.27 ± 0.02)*E*10-38 cm-2. E has been assessed from the energy deposited in the cloud chamber and we have adjusted the cross-section with a straight line as it is expected under the assumption of scale invariance. (A.C.)

  5. Study on Magnesium based Pyrotechnic Composition as a Priming Charge

    Directory of Open Access Journals (Sweden)

    A. S. Redkar

    1996-01-01

    Full Text Available A new pyrotechnic composition containing Mg/KNO3/phenolic resin has been formulated and studied in detail for its sensitivity, mechanical and thermal properties, moisture and environmental effects and performance in a closed vessel. The data generated reveal that this composition shows superior performance, better mechanical properties and less susceptibility to moisture as compared to gunpowder. In addition, performance of the composition under extreme hot (45 degree centigrade and cold (-26 degree centigrade environmental conditions is not affected at all. Differential thermal analyser results indicate that phenolic resin plays a vital role in reducing the ignition temperature of Mg/KNO/sub 3/ system.

  6. Study on tobacco use and awareness among marginalized children

    Directory of Open Access Journals (Sweden)

    S Raval

    2010-01-01

    Full Text Available Background : The current study entailed a survey of children from the lower socioeconomic strata of rural and urban regions of the states of Maharashtra and Assam who are vulnerable to tobacco usage. More than 1700 children were checked for precancerous lesions and 1004 were surveyed for tobacco habits and awareness. Aims: The objective of the survey was to determine and report on all the variant factors affecting the use of tobacco among the underprivileged children population. The aim of the clinical check-up was to detect precancerous lesions in the tobacco-using children at an early treatable stage. Materials and Methods : Awareness lectures and ENT camps were conducted at 12 organizations/community centers. A cross-section of children were interviewed to understand tobacco use among them. All the children were screened for precancerous lesions. Children with suspicious oral lesions were sent for further evaluation at a nearby diagnostic cancer facility. The survey was conducted by trained social workers. Results : The percentage of tobacco users in urban Mumbai was quite low at 4.8% compared with rural Kasara (36% and Assam (76%; and 74.6% of the children were aware that tobacco use was dangerous and harmful to health. The average age of initiation was 9 years. Out of the 1004 children surveyed, 253 were tobacco users and 79% were males. Of the 1700 children screened, 23.5% presented with precancerous oral lesions. Conclusion : This study addresses the tobacco habits of a typical sample of marginalized children in India and the need for effective interventions aiming at reducing the burden of tobacco-related cancers by controlling at the point of initiation.

  7. Children's environmental knowing: A case study of children's experiences during an environmental education programme

    Science.gov (United States)

    Scott, Sandra Anne

    This study explores children's experiences during WaterWorlds (pseudonym) a field-based environmental education programme at a marine science centre. The study objectives were to investigate how children understand and interpret their experiences, and how these experiences foster their environmental knowing. To address these objectives, I carried out a case study at a marine science centre in British Columbia. I examined children's WaterWorlds experiences and explored their environmental understandings and commitment to environmental action. I analysed the experiences of children in four separate classes and carried out an in-depth examination of four individual children. Data were collected using informal semi-structured interviews, observations, conversations, researcher journal logs, and student documents including their writing and illustrations. My findings indicate that the WaterWorlds programme experience fosters children's environmental knowing. Participation in WaterWorlds activities led to connection, caring, and concern for other species and in some cases, for the marine environment as a whole. During the programme, children chose the ways they interpreted and expressed their environmental knowledge, ethic of care, advocacy, and commitment to action. This development of each child's self-expression resulted in motivational and powerful learning experiences that inspired and nurtured their connections to the earth. This research provides evidence and examples of how educators can foster children's environmental knowing through multi-disciplinary environmental education experiences. It illustrates that activities such as observing and documenting the lives of other animal species, collecting data and conducting research on those species, and working and learning alongside experts in the field of environmental education are powerful experiences that motivate concern and care for the earth among children.

  8. Branching Out: Forest Studies with Children.

    Science.gov (United States)

    Argast, Susan; Macdonald, Cheryl

    1996-01-01

    Describes activities which sharpen awareness of trees through the senses in this first of a two-part integrated unit for teaching children about forest ecosystems. Students interact and work in collaborative groups; learn about the impact of forests on daily life; explore the interdependence of plants, animals, soil, water, air, and light; explore…

  9. Charge-magnetic interference resonant scattering studies of ferromagnetic crystals and thin films

    International Nuclear Information System (INIS)

    The element- and site-specificity of X-ray resonant magnetic scattering (XRMS) makes it an ideal tool for furthering our understanding of complex magnetic systems. In the hard X-rays, XRMS is readily applied to most antiferromagnets where the relatively weak resonant magnetic scattering (10-2-10-6Ic) is separated in reciprocal space from the stronger, Bragg charge scattered intensity, Ic. In ferro(ferri)-magnetic materials, however, such separation does not occur and measurements of resonant magnetic scattering in the presence of strong charge scattering are quite challenging. We discuss the use of charge-magnetic interference resonant scattering for studies of ferromagnetic (FM) crystals and layered films. We review the challenges and opportunities afforded by this approach, particularly when using circularly polarized X-rays. We illustrate current capabilities at the Advanced Photon Source with studies aimed at probing site-specific magnetism in ferromagnetic crystals, and interfacial magnetism in films. (authors)

  10. Studies of Space Charge Effects in the Proposed CERN PS2

    Energy Technology Data Exchange (ETDEWEB)

    Qiang, Ji; /LBL, Berkeley; Ryne, Robert; /LBL, Berkeley; De Maria, Riccardo; /Brookhaven; Macridin, Alexandru; /Fermilab; Spentzouris, Panagiotis; /Fermilab; Papaphilippou, Yannis; /CERN; Wienands, Ulrich; /SLAC

    2012-06-22

    A new proton synchrotron, the PS2, is under design study to replace the current proton synchrotron at CERN for the LHC upgrade. Nonlinear space charge effects could cause significant beam emittance growth and particle losses and limit the performance of the PS2. In this paper, we report on studies of the potential space-charge effects at the PS2 using three-dimensional self-consistent macroparticle tracking codes, IMPACT, MaryLie/IMPACT, and Synergia. We will present initial benchmark results among these codes. Effects of space-charge on the emittance growth, especially due to synchrotron coupling, aperture sizes, initial painted distribution, and RF ramping scheme will also be discussed.

  11. A Study On Parental Anxiety Among Visually Impaired And Normal Children

    OpenAIRE

    Nivedha Lakshmi; Zahida Jabeen

    2012-01-01

    The objective of the study is to find out the parental anxiety among the visually impaired children and normal children. In the present investigation, 120 visually impaired children and normal children and their parents were selected. Equal number of 60 subjects belonged to the group of visually impaired children and normal children. Of which 30 were males and females in each group. Both fathers and mothers of these children were selected for the present study. The results of the present stud...

  12. A Study On Parental Anxiety Among Visually Impaired And Normal Children

    OpenAIRE

    Nivedha Lakshmi and Zahida Jabeen

    2012-01-01

    The objective of the study is to find out the parental anxiety among the visually impaired children and normal children. In the present investigation, 120 visually impaired children and normal children and their parents were selected. Equal number of 60 subjects belonged to the group of visually impaired children and normal children. Of which 30 were males and females in each group. Both fathers and mothers of these children were selected for the present study. The results of the pr...

  13. A new charge-tagged proline-based organocatalyst for mechanistic studies using electrospray mass spectrometry

    Directory of Open Access Journals (Sweden)

    J. Alexander Willms

    2014-08-01

    Full Text Available A new 4-hydroxy-L-proline derivative with a charged 1-ethylpyridinium-4-phenoxy substituent has been synthesized with the aim of facilitating mechanistic studies of proline-catalyzed reactions by ESI mass spectrometry. The charged residue ensures a strongly enhanced ESI response compared to neutral unmodified proline. The connection by a rigid linker fixes the position of the charge tag far away from the catalytic center in order to avoid unwanted interactions. The use of a charged catalyst leads to significantly enhanced ESI signal abundances for every catalyst-derived species which are the ones of highest interest present in a reacting solution. The new charged proline catalyst has been tested in the direct asymmetric inverse aldol reaction between aldehydes and diethyl ketomalonate. Two intermediates in accordance with the List–Houk mechanism for enamine catalysis have been detected and characterized by gas-phase fragmentation. In addition, their temporal evolution has been followed using a microreactor continuous-flow technique.

  14. Numerical study for production of space charge within the stratiform cloud

    Indian Academy of Sciences (India)

    A K Srivastava; S N Tripathi

    2010-10-01

    One dimensional numerical model has been developed to predict the production of space charge and variations in other electrical parameters within the low level stratiform type of cloud having very weak vertical motion.Non-linear coupled differential equations which govern ion concentrations,charged and neutral droplet concentrations and electric field were used.Symmetry has been observed in all the electrical parameters within the cloud.The magnitude of average positive ion concentrations was observed to be high as compared to the negative ion concentrations,which is due to low scavenging rate of positive ions than the negative ions,highly attributed to their mobilities.The rate of scavenging of ions affects the concentration of charged droplets,which eventually influence the electric field and thus the space charge density within the cloud.Maximum electric field (max) was observed at middle of the cloud whereas minimum was observed at both the edges of the cloud.Minimum electric field (min) was found to be equal and constant (∼27Vm−1)for any drop concentration.Net positive and negative space charges were observed at the top and bottom of the cloud,respectively.The simulated results show some discrepancies to the natural condition, which are due to simulations made under some basic assumptions and limitations and that will be incorporated in the future studies for natural cloud condition.

  15. Case study Early psychomotor development of children from triple pregnancy – case study

    OpenAIRE

    Łucja Bieleninik; Mariola Bidzan; Aneta Koszewska

    2014-01-01

    The aim of this study was to analyze the specificity and dynamics of psychomotor development in children from triplet pregnancy. The studied group was composed of siblings from triple pregnancy (T1, T2, T3), including two girls and one boy. This longitudinal study comprised three stages: stage I – children aged 25 months, stage II – children aged 29 months, and stage III – children aged 38 months. At each stage, the psychomotor development of children was examined with the Third Edition ...

  16. Myeloproliferative disease in children: a demographic study.

    OpenAIRE

    Reid, M. M.; Saunders, P. W.; Kernahan, J

    1988-01-01

    Over eight years, eight cases of childhood myeloproliferative disease were recognised in the northern region of England (population 3.1 million). Five were classic chronic myeloid leukaemia (CML) and the three others, forms of myeloproliferative disease. No case of juvenile CML was recognised. With the exception of CML, "adult" type myeloproliferative disease of children is underrepresented in the literature and its natural history remains unknown.

  17. XPS studies of MgB2 superconductor for charge state of Mg

    International Nuclear Information System (INIS)

    X-ray photoelectron spectroscopic (XPS) studies have been carried out on polycrystalline MgB2 pellets. Characteristic Mg-2p and B-Is spectra have been analysed for extracting binding energies. There are evidences of MgB2 and formation of traces of metallic Mg, MgO and B2O3. Binding energy of Mg in MgB2 reveals its charge state to be less than 2(+) indicative of partial and not full charge transfer from Mg to B. (author)

  18. Resistive Micromegas for sampling calorimetry, a study of charge-up effects

    Science.gov (United States)

    Chefdeville, M.; Karyotakis, Y.; Geralis, T.; Titov, M.

    2016-07-01

    Micromegas, as a proportional and compact gaseous detector, is well suited for sampling calorimetry. The limitation of occasional sparking has now been lifted by means of resistive electrodes but at the cost of current-dependent charge-up effects. These effects are studied in this contribution, with an emphasis on gain variations during operation at high particle rate and under heavy ionisation. Results are reproduced by a simple model of charging-up which will be used for detector design optimisation in the future.

  19. Kaduna Beggar Children: A Study of Child Abuse and Neglect in Northern Nigeria.

    Science.gov (United States)

    Ojanuga, Durrenda Nash

    1990-01-01

    Pilot study reports on use of children as street beggars in Kaduna, Nigeria. Begging usually occurs because children's parents are poor, disabled. Children may also be handicapped. Other child beggars are poor boys studying with Koranic mallams; children must provide own food and money for lessons by begging. Measures to assist beggar children are…

  20. A nanoscale study of charge extraction in organic solar cells: the impact of interfacial molecular configurations

    Science.gov (United States)

    Tang, Fu-Ching; Wu, Fu-Chiao; Yen, Chia-Te; Chang, Jay; Chou, Wei-Yang; Gilbert Chang, Shih-Hui; Cheng, Horng-Long

    2014-11-01

    In the optimization of organic solar cells (OSCs), a key problem lies in the maximization of charge carriers from the active layer to the electrodes. Hence, this study focused on the interfacial molecular configurations in efficient OSC charge extraction by theoretical investigations and experiments, including small molecule-based bilayer-heterojunction (sm-BLHJ) and polymer-based bulk-heterojunction (p-BHJ) OSCs. We first examined a well-defined sm-BLHJ model system of OSC composed of p-type pentacene, an n-type perylene derivative, and a nanogroove-structured poly(3,4-ethylenedioxythiophene) (NS-PEDOT) hole extraction layer. The OSC with NS-PEDOT shows a 230% increment in the short circuit current density compared with that of the conventional planar PEDOT layer. Our theoretical calculations indicated that small variations in the microscopic intermolecular interaction among these interfacial configurations could induce significant differences in charge extraction efficiency. Experimentally, different interfacial configurations were generated between the photo-active layer and the nanostructured charge extraction layer with periodic nanogroove structures. In addition to pentacene, poly(3-hexylthiophene), the most commonly used electron-donor material system in p-BHJ OSCs was also explored in terms of its possible use as a photo-active layer. Local conductive atomic force microscopy was used to measure the nanoscale charge extraction efficiency at different locations within the nanogroove, thus highlighting the importance of interfacial molecular configurations in efficient charge extraction. This study enriches understanding regarding the optimization of the photovoltaic properties of several types of OSCs by conducting appropriate interfacial engineering based on organic/polymer molecular orientations. The ultimate power conversion efficiency beyond at least 15% is highly expected when the best state-of-the-art p-BHJ OSCs are combined with present arguments

  1. Basic study for a novel combined treatment with a nano-DDS and charged particle therapy

    International Nuclear Information System (INIS)

    To realize a novel cancer therapy, ''Nano-Drug Delivery System (Nano-DDS)-Charged Particle Therapy'', we performed a basic study using multimodal thermo-sensitive polymer-modified liposomes (MTPLs) containing a MR contrast agent, fluorescence dye and anticancer drug. In our previous work, Nano-DDS thermal therapy using the MTPLs was performed for pre-clinical research. The MTPL accumulated in the subcutaneous tumors for over 8 hours after administration, and the temperature-triggered membrane disruption was visualized as a signal enhancement in T1-weighted MRI. The effects of treatment using MTPL with heating were found to increase. The purpose of this year's research was to assess the treatment effects using MTPLs with heating and charged particle therapy, and to evaluate MR signal changes after irradiation with charged particles. (author)

  2. Study on CT changes in autistic children

    International Nuclear Information System (INIS)

    Since 1979 we have performed CT examinations on 132 autistic children. Neurological diagnosis of the lesion was established by Dr. Segawa's group. On the CT of many autistic children, we found a small low density change located in the anterior wall of the temporal horn, or localized dilatation of the inferior horn near the damaged brain. We reviewed 96 of these patients who all had the obvious low density changes, or localized irregular dilatations in the anterior wall of the temporal horn. By measuring the distance of damage from the midline, we divided the 96 cases into two groups. Group 1 consisted of those with damage located laterally more than 30 mm line from the midline. Group 2 consisted of those with damage medially to the 30 mm line from the midline. Those cases with a large lesion both laterally and medially of the 30 mm line were categorized into group 1. In the adult brain the lateral border of the amygdaloid nucleus was never located laterally more than 30 mm from the midline. Laterally over the 30 mm line there were two marked fiber systems running near the anterior wall of the temporal horn: the fiber of the anterior commissure and the uncinate fascicle. Group 1 consisted of 62 patients and group 2 of 34 patients. The majority of the two group patients were pure autism children. This suggested that the main lesion in autism was in the amygdala. (author)

  3. CsI based charged particle array for reaction studies at IUAC

    International Nuclear Information System (INIS)

    Developmental activities in charge particle detector array for investigating reaction dynamics has been initiated at IUAC. The array will consist of CsI(TI) detectors coupled to photo-diode and is being developed to study fusion-fission dynamics and will also serve as an ancillary detector system for National Array of Neutron Detectors (NAND)

  4. Preliminary results from a laboratory study of charging mechanisms in a dusty plasma

    International Nuclear Information System (INIS)

    A laboratory investigation has been developed to experimentally study the interaction of micron sized particles with plasmas and electromagnetic radiation. The intent is to investigate under what conditions particles of various compositions and sizes become charged, or discharged, while exposed to an electron beam. Primary emphasis in this report is on secondary emission of electrons. Preliminary results are presented

  5. Experimental study of charge collection in PN, NP diodes and MOS capacitor struck by heavy ions

    International Nuclear Information System (INIS)

    Charge collection in PN and silicon diodes and MOS capacitor struck by heavy ions, has been experimentally studied. We have analysed a large set of data obtained at GANIL, Saclay and Bruyeres-le-Chatel accelerators. General laws have been deduced to describe the FUNNELING phenomena as function of circuit polarisation and ion penetration

  6. Life-span studies on mice exposed to heavy charged particles or photons

    International Nuclear Information System (INIS)

    The carcinogenic risk associated with heavy charged (HZE) particles is currently undefined. Precise relationships have been established for relative biological effectiveness (RBE) and linear energy transfer (LET) for the killing of cells in vitro and for other short-term (acute) biological responses to charged particles, but comparable information is lacking on carcinogenic response. Experiments are in progress to study induction/promotion of Harderian gland tumors, and the present life-span studies should provide complementary information because it is inferred that over the dose range explored in the present experiments, most of the life shortening is attributable to induction/promotion of neoplastic diseases. The information sought is important both for understanding fundamental mechanisms of radiation carcinogenesis and for assessing the risk of the space radiation environment and of radiation therapy or other medical applications of heavy charged particles in young patients whose life expectancy could permit expression of a tumor. The hypothesis tested in the core experiment, designated SKYHOOK, is that LET dependence for life shortening and excess mortality rates observed after mice are exposed to heavy charged particles (HZE) will conform to existing theory and observations based on other endpoints; namely, a peak RBE at a dose-averaged LET value of approximately 100 keV/μm, with RBE diminishing at lesser and greater values of LET. Because results on cell killing show different RBE values, at the same approximate LET, for different charged particles, the possibility exists that LET by itself is not a fully adequate descriptor for biological response, and physical characteristics such as mass, charge, or velocity may also be of great importance

  7. URINARY TRACT INFECTIONS IN MALE CHILDREN: A PROSPECTIVE OBSERVATIONAL STUDY

    OpenAIRE

    Sarada G; Rafiq Ahmed K; Sudhakar G* and Srilatha

    2015-01-01

    A total of 96 male children with Urinary Tract Infections (UTI) were included in the study to identify the risk factors predisposing to UTI in male children .78.83%  were in <1 yr age and 20.3% were in 1 to 5 yr of age. Dysuria, fever and frequency are the most common symptoms (33%). Culture positivity was only in 35 children (36.36%). E.coli was the most common organism isolated (80%). Urinary tract abnormalities were found in 34/96 (33%). Phimosis was the most common urinary anomaly note...

  8. Pulmonary ventilation and perfusion studies in infants and children

    International Nuclear Information System (INIS)

    Ventilation and perfusion imaging techniques may be applied successfully to the diagnosis of many pulmonary disorders in children. These studies may be performed with relative ease and safety in all patients, even if they are unable to cooperate. The choice of radiopharmaceuticals applicable to children includes inert gases such as xenon 133 and krypton 81m as well as technetium 99m particles for perfusion and aerosol ventilation imaging. Quantitation of regional lung function is readily performed with available techniques. The indications for ventilation and perfusion lung imaging in children differ significantly from those in the adult

  9. Behavioral Pattern during Dental Pain in Intellectually Disabled Children: A Comparative Study

    OpenAIRE

    Shanmugam, Muthukali; Shivakumar, Vetrivel; Anitha, Vijayarangan; Meenapriya, Bagavathi Perumal; Aishwarya, Srinivasan; Anitha, Ramakrishnan

    2014-01-01

    Aim. Children with developmental disabilities generally experience more pain than the normal children. Description of pain is generally difficult in children and more so in children with intellectual disabilities. The study aimed at evaluating dental pain in children with intellectual disabilities. Methods. The survey was carried out in an institution caring for intellectually disabled children to determine the oral health status and the treatment needs of the special kids. 236 children were ...

  10. Exiting Foster Care: A Case Study of Former Foster Children Enrolled in Higher Education in Kansas

    Science.gov (United States)

    Schwandt, Jamie R.

    2013-01-01

    In the United States, foster care is provided to children to avert maltreatment and abuse of children in distressed families by providing a temporary home or a foster home. Courts with jurisdiction over families have been charged by Congress to find appropriate homes when necessary circumstances occur. In fiscal year 2009, there were 423,773…

  11. Gait maturation in children with cerebral palsy: A pilot study

    Directory of Open Access Journals (Sweden)

    J.S. Marques

    2011-01-01

    Full Text Available This study aimed at observing children with cerebral palsy's (CP gait maturation and to correlate gait maturation's motor skill parameters. Podogram and video shooting of eight children's gait were used. Children up to seven years of age participated in the study. Cluster analysis was applied, dividing the sample into two groups, using the relation between pelvis’ width and the spreading of the ankles (REL as parameters. Data were analyzed using t-test, analysis of Deltas, and Pearson’s correlation. Deviance from normality for all the parameters was demonstrated with greater failure in speed and cadence and a significant correlation among these parameters, and yet between them and the REL parameter. Although children with CP had acquired gait, they still do it immaturely.

  12. Ion distributions at charged aqueous surfaces: Synchrotron X-ray scattering studies

    International Nuclear Information System (INIS)

    Surface sensitive synchrotron X-ray scattering studies were performed to obtain the distribution of monovalent ions next to a highly charged interface at room temperature. To control surface charge density, lipids, dihexadecyl hydrogen-phosphate (DHDP) and dimysteroyl phosphatidic acid (DMPA), were spread as monolayer materials at the air/water interface, containing CsI at various concentrations. Five decades in bulk concentrations (CsI) are investigated, demonstrating that the interfacial distribution is strongly dependent on bulk concentration. We show that this is due to the strong binding constant of hydronium H3O+ to the phosphate group, leading to proton-transfer back to the phosphate group and to a reduced surface charge. Using anomalous reflectivity off and at the L3 Cs+ resonance, we provide spatial counterion (Cs+) distributions next to the negatively charged interfaces. The experimental ion distributions are in excellent agreement with a renormalized surface charge Poisson-Boltzmann theory for monovalent ions without fitting parameters or additional assumptions. Energy Scans at four fixed momentum transfers under specular reflectivity conditions near the Cs+ L3 resonance were conducted on 10-3 M CsI with DHDP monolayer materials on the surface. The energy scans exhibit a periodic dependence on photon momentum transfer. The ion distributions obtained from the analysis are in excellent agreement with those obtained from anomalous reflectivity measurements, providing further confirmation to the validity of the renormalized surface charge Poisson-Boltzmann theory for monovalent ions. Moreover, the dispersion corrections f0 and f00 for Cs+ around L3 resonance, revealing the local environment of a Cs+ ion in the solution at the interface, were extracted simultaneously with output of ion distributions.

  13. Ion distributions at charged aqueous surfaces: Synchrotron X-ray scattering studies

    Energy Technology Data Exchange (ETDEWEB)

    Bu, Wei [Iowa State Univ., Ames, IA (United States)

    2009-01-01

    Surface sensitive synchrotron X-ray scattering studies were performed to obtain the distribution of monovalent ions next to a highly charged interface at room temperature. To control surface charge density, lipids, dihexadecyl hydrogen-phosphate (DHDP) and dimysteroyl phosphatidic acid (DMPA), were spread as monolayer materials at the air/water interface, containing CsI at various concentrations. Five decades in bulk concentrations (CsI) are investigated, demonstrating that the interfacial distribution is strongly dependent on bulk concentration. We show that this is due to the strong binding constant of hydronium H3O+ to the phosphate group, leading to proton-transfer back to the phosphate group and to a reduced surface charge. Using anomalous reflectivity off and at the L3 Cs+ resonance, we provide spatial counterion (Cs+) distributions next to the negatively charged interfaces. The experimental ion distributions are in excellent agreement with a renormalized surface charge Poisson-Boltzmann theory for monovalent ions without fitting parameters or additional assumptions. Energy Scans at four fixed momentum transfers under specular reflectivity conditions near the Cs+ L3 resonance were conducted on 10-3 M CsI with DHDP monolayer materials on the surface. The energy scans exhibit a periodic dependence on photon momentum transfer. The ion distributions obtained from the analysis are in excellent agreement with those obtained from anomalous reflectivity measurements, providing further confirmation to the validity of the renormalized surface charge Poisson-Boltzmann theory for monovalent ions. Moreover, the dispersion corrections f0 and f00 for Cs+ around L3 resonance, revealing the local environment of a Cs+ ion in the solution at the interface, were extracted simultaneously with output of ion distributions.

  14. A spectroscopic study of factors affecting charge transfer at organo-metallic interfaces

    International Nuclear Information System (INIS)

    The properties of organic films produced by the Langmuir-Blodgett (LB) technique have become more widely known in the last few decades, as the variety of organic molecules suitable for this method of production has increased. One class of LB molecule receiving particular attention has been that of conjugated polymers. These organic materials exhibit an anisotropic semi-conductor like behavior along the polymer chain, making them suitable candidate materials for use in molecular electronic devices. However, the exact nature of multiple charge transport mechanisms is still an area worthy of investigation. Through the development in this work of a dosimetric device, suitable for the study of a number of different radiation types, several difficulties associated with the charge extraction from organic materials, by means of metallic electrodes, were clearly illustrated. Some of these problems were likely to have been caused by charge trapping within the film itself. However, it is the trapping at the boundary between the LB film and metallic electrode, where there is a mismatch in electronic energy levels, which has been the main investigation of this work. To that end a number of different spectroscopic investigations were undertaken in order to pinpoint various factors affecting the efficiency in the transport of charge across the interface region. Extensive low energy Positron Doppler Broadened Annihilation Spectroscopy (DBARS) measurements were made on 12-8 polydiacetylene and ω-tricosenoic acid LB films. The resulting analyses have allowed comparison of charge trapping within the different bulk films and also at the film to substrate interface. In addition to DBARS, Fourier Transform Infra-red (FTIR) and Near Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopies have been used to investigate the factors affecting the carboxylic acid group at the head of the LB molecule and the role this plays in charge transport across the organo-metallic boundary. (author)

  15. Study of Mothers' Anxieties Related to Their Children's Future

    Science.gov (United States)

    Ilgar, Sengul

    2015-01-01

    The purpose of this study is to study anxieties of mothers related to their children's future. Qualitative method was used in order to study anxieties of mothers from different socio-economic levels. Sample of the study participants are 129 mothers living in Istanbul. 32 of those mothers are from upper socio-economic level, 57, from middle…

  16. Fiction, children's voices and the moral imagination: a case study

    OpenAIRE

    Milne, Stephen

    2008-01-01

    The importance of stories in educating the moral imagination of the child provides the context for this thesis, which explores children's responses to the moral dimension of fiction. Studies in narrative psychology, literary theory and children's responses to reading also provide the empirical and theoretical background for this qualitative enquiry that compares a number of developing readers' responses to fiction in a school and classroom context. Focusing on the features that distinguish th...

  17. Services for children with learning disabilities – questionnaire based study

    OpenAIRE

    Beard, Maria

    2010-01-01

    Abstract Aims - This study aimed to explore parents’ experiences and opinions of accessing current services for children with learning disabilities, including direct payments. Background – Current government policy and legislation emphasises that children with disabilities are a priority area. In particular policy indicates a need to empower parent’s choice and control over the services they receive by promoting the use of direct payments and short breaks. Despite this very little is...

  18. Traumatic dental injuries in Serbian children: Epidemiological study

    OpenAIRE

    Vuković Ana; Marković Dejan; Petrović Bojan; Apostolović Mirjana; Golijanin Ranko; Kanjevac Tatjana; Stojković Branislava; Perić Tamara; Blagojević Duška

    2013-01-01

    Introduction. Comprehensive epidemiological data regarding factors associated with traumatic dental injuries are scarce. Objective. The aim of the present study was to assess the frequency and analyze the factors associated with traumatic dental injuries in Serbian children. Methods. Research included children and adolescents with traumatic dental injury aged 0-19 year during the period from 2003 to 2010, in four University Dental Centres in Serbia: Belgrad...

  19. STUDY OF LACTOSE INTOLERANCE IN CHILDREN BELOW 24 M ONTHS

    OpenAIRE

    Shabd Singh; Rawat; Singh,, R.; Sunil

    2013-01-01

    ABSTRACT: OBJECTIVE: To study the incidence of transient lactose intole rance in children below 24 months and to determine the need of discon tinuation of breast feeding and necessity of lactose free formula. MATERIAL AND METHODS: Randomly selected 100 children below 24 months of age, who were admitted in department of p ediatrics, S.S. Medical College and Associated G.M. Hospital Rewa, 70 of them were grou ped as cases with diarrhea, abdominal distentio...

  20. Pilot Study: Swimming for Children with Cerebral Palsy.

    OpenAIRE

    Declerck, Marlies; Daly, Daniel; Feys, Hilde

    2013-01-01

    The aim of this study was to investigate the effects of a swimming program on body function, activity and Quality of Life (QOL), in children diagnosed with Cerebral Palsy. Seven children (female/male: 4/3; Median 10.2 years old; Gross Motor Function Classification Scale I to III) participated in a 6-week swimming intervention using a case series design. Outcome measures were, for body function level: handgrip strength; for activity level: unimanual speed performance, walking capacity, gross m...

  1. Improved charge-coupled device detectors for high-speed, charge exchange spectroscopy studies on the DIII-D tokamak

    International Nuclear Information System (INIS)

    Charge exchange spectroscopy is one of the key ion diagnostics on the DIII-D tokamak. It allows determination of ion temperature, poloidal and toroidal velocity, impurity density, and radial electric field Er throughout the plasma. For the 2003 experimental campaign, we replaced the intensified photodiode array detectors on the central portion of the DIII-D charge exchange spectroscopy system with advanced charge-coupled device (CCD) detectors mounted on faster (f/4.7) Czerny-Turner spectrometers equipped with toroidal mirrors. The CCD detectors are improved versions of the ones installed on our edge system in 1999. The combination improved the photoelectron signal level by about a factor of 20 and the signal to noise by a factor of 2-8, depending on the absolute signal level. The new cameras also allow shorter minimum integration times while archiving to PC memory: 0.552 ms for the slower, lower-read noise (15 e) readout mode and 0.274 ms in the faster, higher-read noise (30 e) mode

  2. Assessment of mastication in healthy children and children with cerebral palsy: a validity and consistency study

    NARCIS (Netherlands)

    Remijn, L.; Speyer, R.; Groen, B.E.; Holtus, P.C.; Limbeek, J. van; Nijhuis-Van der Sanden, M.W.G.

    2013-01-01

    The aim of this study was to develop the Mastication Observation and Evaluation instrument for observing and assessing the chewing ability of children eating solid and lumpy foods. This study describes the process of item definition and item selection and reports the content validity, reproducibilit

  3. [Street food among children: a study in north Tunisia].

    Science.gov (United States)

    Neffati, Larbi; Ridha, Hamza; Kolsteren, Patrick; Hilderbrand, Katherine

    2004-01-01

    As urbanization increases in Tunisia, eating meals outside the home is becoming more frequent. Children are prime consumers for the fast food sold in the streets. Neither their nor their parents' attitude towards street food is well documented as yet. This study was conducted in the city of Bizerte in February 1998. Its aim was to gather information about street food and parents' and children's attitudes towards it to help organize educational sessions with the children, parents, teachers, and vendors. The study interviewed 421 primary school children, ranging in age from 6 to 15 years (mean age: 10 years), from 24 schools. Half received pocket money, a percentage that did not differ by sex. Three quarters of the children used more than 75% of their pocket money to buy street food. The items bought most frequently were candy (27.2%), sandwiches (23.9%), pastries (23.9%), sunflower seeds and peanuts (21%), and either pizza, chocolate, or cheese (20.3%); the largest proportion of money was spent on sandwiches. In more than half the cases (55.7% of the children), the main motivation for buying street food was either to replace or fill out a meal at home, with sandwiches or pastries. The parents' monthly income did not influence the children's purchasing behavior, but the rhythm of receiving pocket money did. Most children were satisfied with the nutritional and hygienic quality of the food available, but their opinion of this quality as well as the reasons for buying the food and the prices spent on it differed considerably from that of their parents. This study highlights the important role of street foods in the daily diet of schoolchildren and the need for appropriate nutrition education in primary schools. PMID:15217744

  4. Impact of nutrition messages on children's food choice: pilot study.

    Science.gov (United States)

    Bannon, Katie; Schwartz, Marlene B

    2006-03-01

    This pilot study tested the influence of nutrition message framing on snack choice among kindergarteners. Three classrooms were randomly assigned to watch one of the following 60s videos: (a) a gain-framed nutrition message (i.e. the positive benefits of eating apples) (n=14); (b) a loss-framed message (i.e. the negative consequences of not eating apples) (n=18); or (c) a control scene (children playing a game) (n=18). Following this, the children were offered a choice between animal crackers and an apple for their snack. Among the children who saw one of the nutrition message videos, 56% chose apples rather than animal crackers; in the control condition only 33% chose apples. This difference was statistically significant (chi2=7.56, p<0.01). These results suggest that videos containing nutritional messages may have a positive influence on children's short-term food choices. PMID:16442667

  5. Charging studies of heat packs using parabolic dish solar energy concentrator for extreme conditions

    Science.gov (United States)

    Kumar, Rohitash; Vyas, Sumita; Kumar, Ravindra; Dixit, Ambesh

    2016-05-01

    Parabolic dish solar energy concentrator with aperture diameter 1.4 m and focal length 0.32 m is designed and fabricated to charge and store solar thermal energy in phase change material (PCM) based heat packs. Overall heat loss factor, heat duty, over all thermal efficiency, and optical efficiency factor are calculated using water sensible heating and cooling tests and values are 16.11 W m-2 K-1, 546.9 W, 49.2% and 0.62 respectively. The performance characteristic curve is generated using these parameters to understand its performance at different ambient temperatures and solar insolation. The fabricated concentrator has been used to charge 16 PCM heat packs with 150 g PCM in each heat pack, which took about 35 minutes for complete charging of PCM heat packs at average ambient temperature 39 °C and solar radiation flux density 715 W m-2 K-1. The charged heat packs are subjected to discharge studies at average ambient temperature about - 7 °C and observed heat release in the temperature range of 48 to 40 °C for 50 minutes, suggesting its applications for comfort and therapeutic applications in high altitude areas.

  6. Charge collection studies of proton-irradiated n- and p-type epitaxial silicon detectors

    International Nuclear Information System (INIS)

    Proton-irradiated epitaxial pad diodes of 75, 100 and 150μm thickness and different oxygen concentrations were studied as an option to withstand the extreme radiation environment in the innermost tracking region of the future Super-LHC. With a new TCT setup using red laser light, time-resolved current signals could be measured in 150μm thin diodes. Thus the charge correction method (CCM) could be used to extract the effective trapping times. Similar results compared to previously investigated materials were obtained if the standard model of trapping is assumed, which is based on a constant trapping time at each fluence and neglects detrapping and charge multiplication. Charge collection efficiency (CCE) measured with 5.8 MeV α-particles showed an increase for decreasing thickness, but no dependence on impurity concentration was seen. CCE simulations based on the effective trapping time constants determined with the CCM resulted in systematically lower values than the measurements. This is the case for the CCE of both α-particles, red and infrared laser light. To account for this, possible modifications of the trapping model including voltage- or field-dependent trapping times will be discussed. Moreover, at high fluences and voltages anomalously high CCE>1 was observed, which indicates charge multiplication effects.

  7. Theoretical study on charge injection and transport properties of six emitters with push–pull structure

    International Nuclear Information System (INIS)

    Highlights: • We investigated six small organic molecules by using computational approaches. • This investigation is mainly based on the Marcus electron transfer theory. • The density functional theory (DFT) was used in this investigation. • The IP, EA, reorganization energy and transfer integral were calculated. • We analyzed the charge properties of the molecules by using the computed results. - Abstract: The charge injection and transport properties of six organic light-emitting molecules with push–pull structures were studied by theoretical calculations. The ground-state geometries for the neutral, cationic and anionic states were optimized using density functional theory. Subsequently, the ionization potentials and electron affinities were calculated. We computed the reorganization energies and the transfer integrals based on the Marcus electron transfer theory. It was found that in addition to being emitters the six compounds are multifunctional materials being capable of transport for both holes and electrons. Moreover, the double-branched compound DCDPC2 was found to have higher charge injection ability and better balanced charge transport properties than single-branched compounds

  8. The study towards high intensity high charge state laser ion sources

    Science.gov (United States)

    Zhao, H. Y.; Jin, Q. Y.; Sha, S.; Zhang, J. J.; Li, Z. M.; Liu, W.; Sun, L. T.; Zhang, X. Z.; Zhao, H. W.

    2014-02-01

    As one of the candidate ion sources for a planned project, the High Intensity heavy-ion Accelerator Facility, a laser ion source has been being intensively studied at the Institute of Modern Physics in the past two years. The charge state distributions of ions produced by irradiating a pulsed 3 J/8 ns Nd:YAG laser on solid targets of a wide range of elements (C, Al, Ti, Ni, Ag, Ta, and Pb) were measured with an electrostatic ion analyzer spectrometer, which indicates that highly charged ions could be generated from low-to-medium mass elements with the present laser system, while the charge state distributions for high mass elements were relatively low. The shot-to-shot stability of ion pulses was monitored with a Faraday cup for carbon target. The fluctuations within ±2.5% for the peak current and total charge and ±6% for pulse duration were demonstrated with the present setup of the laser ion source, the suppression of which is still possible.

  9. The study towards high intensity high charge state laser ion sources.

    Science.gov (United States)

    Zhao, H Y; Jin, Q Y; Sha, S; Zhang, J J; Li, Z M; Liu, W; Sun, L T; Zhang, X Z; Zhao, H W

    2014-02-01

    As one of the candidate ion sources for a planned project, the High Intensity heavy-ion Accelerator Facility, a laser ion source has been being intensively studied at the Institute of Modern Physics in the past two years. The charge state distributions of ions produced by irradiating a pulsed 3 J/8 ns Nd:YAG laser on solid targets of a wide range of elements (C, Al, Ti, Ni, Ag, Ta, and Pb) were measured with an electrostatic ion analyzer spectrometer, which indicates that highly charged ions could be generated from low-to-medium mass elements with the present laser system, while the charge state distributions for high mass elements were relatively low. The shot-to-shot stability of ion pulses was monitored with a Faraday cup for carbon target. The fluctuations within ±2.5% for the peak current and total charge and ±6% for pulse duration were demonstrated with the present setup of the laser ion source, the suppression of which is still possible. PMID:24593615

  10. Studies of highly charged ions with EBIT and Super-EBIT

    International Nuclear Information System (INIS)

    The LLNL electron beam ion traps provide cold highly charged ions up to bare U. These machines have provided a wealth of atomic physics data using a compact, relatively inexpensive, device. The physics program has studied electron-ion collisions, QED, ion-surface interactions, and plasmas physics among many other topics. The prospects for the study of the highest charge states in the highest Z ions led to the beam energy upgrade of the first EBIT into Super-EBIT. The desire to use ions as a research probe in themselves led to an ion extraction program on EBIT-2. Finally, a Penning trap (referred to as the RETRAP) has been constructed to catch extracted ions where they can be further cooled and studied. Results of several experiments at the LLNL EBIT facility are described. The program's capabilities are discussed

  11. Children and Clinical Studies: Why Clinical Studies Are Important

    Medline Plus

    Full Text Available ... Systematic Evidence Reviews & Clinical Practice Guidelines Resources Continuing Education Researchers Funding Training & Career Development Division of Intramural Research Research Resources Research Meeting Summaries Technology Transfer Clinical Trials What Are Clinical Trials? Children & ...

  12. Status of oral health awareness in Indian children as compared to Western children: A thought provoking situation (A pilot study

    Directory of Open Access Journals (Sweden)

    Grewal Navneet

    2007-03-01

    Full Text Available A study was conducted to evaluate the level of oral health awareness in a selected sample of Indian children and a selected sample of western children residing in Amritsar city of Punjab. Children were evaluated on the basis of a standardized questionnaire developed by WHO, for health awareness in children. Final results revealed the level of awareness in both the groups and the practical application of their knowledge about dental health in day to day life.

  13. Charged Leptons

    CERN Document Server

    Albrecht, J; Babu, K; Bernstein, R H; Blum, T; Brown, D N; Casey, B C K; Cheng, C -h; Cirigliano, V; Cohen, A; Deshpande, A; Dukes, E C; Echenard, B; Gaponenko, A; Glenzinski, D; Gonzalez-Alonso, M; Grancagnolo, F; Grossman, Y; Harnik, R; Hitlin, D G; Kiburg, B; Knoepfe, K; Kumar, K; Lim, G; Lu, Z -T; McKeen, D; Miller, J P; Ramsey-Musolf, M; Ray, R; Roberts, B L; Rominsky, M; Semertzidis, Y; Stoeckinger, D; Talman, R; Van De Water, R; Winter, P

    2013-01-01

    This is the report of the Intensity Frontier Charged Lepton Working Group of the 2013 Community Summer Study "Snowmass on the Mississippi", summarizing the current status and future experimental opportunities in muon and tau lepton studies and their sensitivity to new physics. These include searches for charged lepton flavor violation, measurements of magnetic and electric dipole moments, and precision measurements of the decay spectrum and parity-violating asymmetries.

  14. Study of Optimal Perimetric Testing in Children (OPTIC: Feasibility, Reliability and Repeatability of Perimetry in Children.

    Directory of Open Access Journals (Sweden)

    Dipesh E Patel

    Full Text Available To investigate feasibility, reliability and repeatability of perimetry in children.A prospective, observational study recruiting 154 children aged 5-15 years, without an ophthalmic condition that affects the visual field (controls, identified consecutively between May 2012 and November 2013 from hospital eye clinics. Perimetry was undertaken in a single sitting, with standardised protocols, in a randomised order using the Humphrey static (SITA 24-2 FAST, Goldmann and Octopus kinetic perimeters. Data collected included test duration, subjective experience and test quality (incorporating examiner ratings on comprehension of instructions, fatigue, response to visual and auditory stimuli, concentration and co-operation to assess feasibility and reliability. Testing was repeated within 6 months to assess repeatability.Overall feasibility was very high (Goldmann=96.1%, Octopus=89% and Humphrey=100% completed the tests. Examiner rated reliability was 'good' in 125 (81.2% children for Goldmann, 100 (64.9% for Octopus and 98 (63.6% for Humphrey perimetry. Goldmann perimetry was the most reliable method in children under 9 years of age. Reliability improved with increasing age (multinomial logistic regression (Goldmann, Octopus and Humphrey, p<0.001. No significant differences were found for any of the three test strategies when examining initial and follow-up data outputs (Bland-Altman plots, n=43, suggesting good test repeatability, although the sample size may preclude detection of a small learning effect.Feasibility and reliability of formal perimetry in children improves with age. By the age of 9 years, all the strategies used here were highly feasible and reliable. Clinical assessment of the visual field is achievable in children as young as 5 years, and should be considered where visual field loss is suspected. Since Goldmann perimetry is the most effective strategy in children aged 5-8 years and this perimeter is no longer available, further

  15. Using singing to nurture children's hearing? A pilot study.

    Science.gov (United States)

    Welch, Graham F; Saunders, Jo; Edwards, Sian; Palmer, Zoe; Himonides, Evangelos; Knight, Julian; Mahon, Merle; Griffin, Susanna; Vickers, Deborah A

    2015-09-01

    This article reports a pilot study of the potential benefits of a sustained programme of singing activities on the musical behaviours and hearing acuity of young children with hearing impairment (HI). Twenty-nine children (n=12 HI and n=17 NH) aged between 5 and 7 years from an inner-city primary school in London participated, following appropriate ethical approval. The predominantly classroom-based programme was designed by colleagues from the UCL Institute of Education and UCL Ear Institute in collaboration with a multi-arts charity Creative Futures and delivered by an experienced early years music specialist weekly across two school terms. There was a particular emphasis on building a repertoire of simple songs with actions and allied vocal exploration. Musical learning was also supported by activities that drew on visual imagery for sound and that included simple notation and physical gesture. An overall impact assessment of the pilot programme embraced pre- and post-intervention measures of pitch discrimination, speech perception in noise and singing competency. Subsequent statistical data analyses suggest that the programme had a positive impact on participant children's singing range, particularly (but not only) for HI children with hearing aids, and also in their singing skills. HI children's pitch perception also improved measurably over time. Findings imply that all children, including those with HI, can benefit from regular and sustained access to age-appropriate musical activities. PMID:26561889

  16. Dynamics of Sewage Charge Policies, Environmental Protection Industry and Polluting Enterprises—A Case Study in China

    OpenAIRE

    Qingsong Wang; Xueliang Yuan; Jian Zuo; Ruimin Mu; Lixin Zhou; Mingxia Sun

    2014-01-01

    The game model of sewage charges, based on incremental mode, was developed. Four modes of high/low sewage charge standards were utilized to analyze the relationship between control strategy on sewage discharge and the development of environmental protection industry. Results showed that the selection of control strategy was heavily dependent on the level of sewage charges. An empirical study was carried out to investigate the environmental protection industry in 31 regions in China in 2010. I...

  17. Photodissociation and charge transfer dynamics of negative ions studied with femtosecond photoelectron spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Zanni, Martin T.

    1999-12-17

    This dissertation presents studies aimed at understanding the potential energy surfaces and dynamics of isolated negative ions, and the effects of solvent on each. Although negative ions play important roles in atmospheric and solution phase chemistry, to a large extent the ground and excited state potential energy surfaces of gas phase negative ions are poorly characterized, and solvent effects even less well understood. In an effort to fill this gap, the author's coworkers and the author have developed a new technique, anion femtosecond photoelectron spectroscopy, and applied it to gas phase photodissociation and charge transfer processes. Studies are presented that (1) characterize the ground and excited states of isolated and clustered anions, (2) monitor the photodissociation dynamics of isolated and clustered anions, and (3) explore the charge-transfer-to-solvent states of atomic iodide clustered with polar and non-polar solvents.

  18. Numerical Studies of Electromagnetic Instabilities in Intense Charged Particle Beams with Large Energy Anisotropy

    CERN Document Server

    Startsev, Edward; Lee, Wei-li

    2005-01-01

    In intense charged particle beams with large energy anisotropy, free energy is available to drive transverse electromagnetic Weibel-type instabilities. Such slow-wave transverse electromagnetic instabilities can be described by the so-called Darwin model, which neglects the fast-wave portion of the displacement current. The Weibel instability may also lead to an increase in the longitudinal velocity spread, which would make the focusing of the beam difficult and impose a limit on the minimum spot size achievable in heavy ion fusion experiments. This paper reports the results of recent numerical studies of the Weibel instability using the Beam Eigenmode And Spectra (bEASt) code for space-charge-dominated, low-emittance beams with large tune depression. To study the nonlinear stage of the instability, the Darwin model is being developed and incorporated into the Beam Equilibrium Stability and Transport(BEST) code.

  19. Photodissociation and charge transfer dynamics of negative ions studied with femtosecond photoelectron spectroscopy

    International Nuclear Information System (INIS)

    This dissertation presents studies aimed at understanding the potential energy surfaces and dynamics of isolated negative ions, and the effects of solvent on each. Although negative ions play important roles in atmospheric and solution phase chemistry, to a large extent the ground and excited state potential energy surfaces of gas phase negative ions are poorly characterized, and solvent effects even less well understood. In an effort to fill this gap, the author's coworkers and the author have developed a new technique, anion femtosecond photoelectron spectroscopy, and applied it to gas phase photodissociation and charge transfer processes. Studies are presented that (1) characterize the ground and excited states of isolated and clustered anions, (2) monitor the photodissociation dynamics of isolated and clustered anions, and (3) explore the charge-transfer-to-solvent states of atomic iodide clustered with polar and non-polar solvents

  20. Study on dielectric charging in low-stress silicon nitride with the MIS structure for reliable MEMS applications

    International Nuclear Information System (INIS)

    Charge-induced failure has been recognized as a primary reliability issue in capacitive micro-actuators. In this paper, we present a simple method to assess the effect of dielectric charging on reliability of a capacitive micro-actuator. By capacitance–voltage measurements for a metal–insulator–semiconductor (MIS) structure, the characteristics of dielectric charging can be investigated, and the obtained results can be used to study the charging behavior of a capacitive micro-actuator. An analytical model based on this method has been established. The silicon-rich nitride film was deposited by low-pressure chemical vapor deposition on silicon substrate. The current–voltage and capacitance–voltage measurements exhibit an asymmetric electrical characteristic under different polarity of stress voltage. The charging parameters of the silicon-rich nitride were extracted by the stretched exponential curve fitting method. This charging behavior suggests that silicon-rich nitride can be negatively or positively charged, and the injection and transport of holes are more favored than the injection and transport of electrons. The charge injection from movable electrode plays a dominant role in the dielectric charging of a capacitive micro-actuator. It is expected that the charge accumulation in dielectrics can be eliminated by employing the bipolar square-wave voltage to actuate a capacitive micro-actuator.

  1. Extremity fractures in children: a hospital based study in Tehran

    Institute of Scientific and Technical Information of China (English)

    Ali Khaji; Mousa Zargar; Mojgan Karbakhsh

    2010-01-01

    Objective: Although long bone fracture in children is not life-threatening, it may cause major disability, loss of working days and severe psychological distress. We conducted this study to determine the pattern of extremity fracture due to trauma in children.Methods: During one year in six general hospitals in Tehran, trauma patients who were hospitalized for more than 24 hours and sustained injuries within seven days before admission were included in the study. The records of children (≤16 years old) hospitalized in six general hospitals in Tehran due to trauma were reviewed prospectively.Results: During the study period, 1274 children had sustained extremity fractures. Male to female ratio was 3.6/1, with the mean age of (10.3±4.2) years. Falls and traffic crashes were the main causes of injuries, with the percentages of 57.3% and 37.1%, respectively. Simple fall (falling on the ground) consisted 60% of patients that sustained fall-related injuries. Pedestrians and bicycle riders comprised most of the cases that were injured due to traffic crashes. Of our cases, 56.8% sustained fractures in the upper extremities and 43.2% in the lower extremities. Forearm was the most common fracture site (34.1%). Comparing our results in preschool and school-age children, falls were the main cause of injuries in both groups, but fractures of lower extremities were significantly more common in preschool children.Conclusions:Improvement of physical condition of sidewalks and crossings in roads will be necessary for prevention of injuries. More attention to safety of home environment should be paid for control of preschools' injury at home. Education of children and adults is necessary to reduce injuries resulting from road traffic crashes.

  2. Screening Preschool Children for Visual Disorders: A Pilot Study

    Directory of Open Access Journals (Sweden)

    Suman Adhikari, BOptom

    2013-12-01

    Full Text Available Purpose: Ocular and/or vision defects are one of the most common reasons for the referral of young children to the hospital. Vision disorders are the fourth most common disability of children and the leading cause of handicapping conditions in childhood. In preschool-age children, amblyopia and amblyogenic risk factors, such as strabismus and significant refractive errors, are the most prevalent and important visual disorders. The purpose of this pilot study was to determine the prevalence of visual disorders in preschool children in Kathmandu Valley, Nepal.Methods: Four hundred and eighty-four children attending eight preschools in Kathmandu Valley underwent detailed optometric examination. Visual acuity was assessed with either Sheridan Gardiner or Kay Picture chart monocularly. Binocularity was assessed with cover test and prism bar neutralisation. Refraction was carried out in all children. In most instances this was done without the use of a cycloplegic agent. Stereopsis was assessed with the Lang stereo test. Anterior and posterior segment abnormalities were assessed by using a pen light, hand-held slit lamp, and direct ophthalmoscope.Results: Refractive error was the most common visual disorder. Considering our criteria of refractive error for myopia ≥ 0.50 D, hyperopia ≥ 1.50 D, astigmatism ≥ 1.00 D, and anisometropia ≥ 1.00 D, the overall prevalence of refractive error in our study was 31.82%. The overall prevalence of myopia, hyperopia, and astigmatism was 24.17%, 2.48%, and 5.17%, respectively. Anisometropia was present in 1.65% of the participants, and 2%, 1.4%, and 0.2% had strabismus, amblyopia, and nystagmus, respectively.Conclusion: The relatively high prevalence of refractive error in our studied population needs more attention. The results suggest that there is a need for a large-scale community-based preschool screening program in Nepal so that affected children can be identified early and appropriate treatment can be

  3. Open Access Article Processing Charges (OA APC) Longitudinal Study 2015 Preliminary Dataset

    OpenAIRE

    Morrison, Heather; Mondésir, Guinsly; Salhab, Jihane; Villamizar, César; Calvé-Genest, Alexis; Desautels, Lisa

    2016-01-01

    This article documents Open access article processing charges (OA APC) longitudinal study 2015 preliminary dataset available for download from the OA APC dataverse [1]. This dataset was gathered as part of Sustaining the Knowledge Commons (SKC), a research program funded by Canada’s Social Sciences and Humanities Research Council. The overall goal of SKC is to advance our collective knowledge about how to transition scholarly publishing from a system dependent on subscriptions and purchase to...

  4. Numerical Study on the Charge Transport in a Space between Concentric Circular Cylinders

    OpenAIRE

    Suh, Y. K.; Baek, K H

    2014-01-01

    Electrification is one of the key factors to be considered in the design of power transformers utilizing dielectric liquid as a coolant. Compared with enormous quantity of experimental and analytical studies on electrification, numerical simulations are very few. This paper describes essential elements of numerical solution methods for the charge transport equations in a space between concentric cylinders. It is found that maintaining the conservation property of the convective terms in the g...

  5. Study of charge-phase diagrams for coupled system of Josephson junctions

    Science.gov (United States)

    Hamdipour, M.; Shukrinov, Y. U. M.

    2010-11-01

    Dynamics of stacked intrinsic Josephson junctions (IJJ) in the high-Tc superconductors is theoretically investigated. We calculate the current-voltage characteristics (CVC) of IJJ and study the breakpoint region on the outermost branch of the CVC for the stacks with 9 IJJ. A method for investigation of the fine structure in CVC of IJJ based on the recording the "phase-charge" diagrams is suggested. It is demonstrated that this method reflects the main features of the breakpoint region.

  6. Study of charge-phase diagrams for coupled system of Josephson junctions

    OpenAIRE

    Hamdipour, M.; Shukrinov, Yu M.

    2010-01-01

    Dynamics of stacked intrinsic Josephson junctions (IJJ) in the high-Tc superconductors is theoretically investigated. We calculate the current-voltage characteristics (CVC) of IJJ and study the breakpoint region on the outermost branch of the CVC for the stacks with 9 IJJ. A method for investigation of the fine structure in CVC of IJJ based on the recording the "phase-charge" diagrams is suggested. It is demonstrated that this method reflects the main features of the breakpoint region.

  7. In-situ Studies of Highly Charged Ions at the LLNL EBIT

    Energy Technology Data Exchange (ETDEWEB)

    Beiersdorfer, P

    2001-08-16

    The properties of highly charged ions and their interaction with electrons and atoms is being studied in-situ at the LLNL electron beam ion traps, EBIT-II and SuperEBIT. Spectroscopic measurements provide data on electron-ion and ion-atom interactions as well as accurate transition energies of lines relevant for understanding QED, nuclear magnetization, and the effects of relativity on complex, state-of-the-art atomic calculations.

  8. Longitudinal adaptation in language development: a study of typically-developing children and children with ASD

    DEFF Research Database (Denmark)

    Weed, Ethan; Fusaroli, Riccardo; Fein, Deborah;

    ’s previous behavior. In this study, we tested this model of mutual influence in a longitudinal corpus (6 visits over 2 years), consisting of 30 minutes of controlled playful activities between parents and 66 children (33 ASD and 33 matched typically developing (TD), Goodwin et al. 2012). Methods: We first...

  9. Reading and visual search: a developmental study in normal children.

    Directory of Open Access Journals (Sweden)

    Magali Seassau

    Full Text Available Studies dealing with developmental aspects of binocular eye movement behaviour during reading are scarce. In this study we have explored binocular strategies during reading and during visual search tasks in a large population of normal young readers. Binocular eye movements were recorded using an infrared video-oculography system in sixty-nine children (aged 6 to 15 and in a group of 10 adults (aged 24 to 39. The main findings are (i in both tasks the number of progressive saccades (to the right and regressive saccades (to the left decreases with age; (ii the amplitude of progressive saccades increases with age in the reading task only; (iii in both tasks, the duration of fixations as well as the total duration of the task decreases with age; (iv in both tasks, the amplitude of disconjugacy recorded during and after the saccades decreases with age; (v children are significantly more accurate in reading than in visual search after 10 years of age. Data reported here confirms and expands previous studies on children's reading. The new finding is that younger children show poorer coordination than adults, both while reading and while performing a visual search task. Both reading skills and binocular saccades coordination improve with age and children reach a similar level to adults after the age of 10. This finding is most likely related to the fact that learning mechanisms responsible for saccade yoking develop during childhood until adolescence.

  10. Saccades improve postural control: a developmental study in normal children.

    Directory of Open Access Journals (Sweden)

    Layla Ajrezo

    Full Text Available INTRODUCTION: Dual-task performance is known to affect postural stability in children. This study focused on the effect of oculomotor tasks like saccadic eye movements on postural stability, studied in a large population of children by recording simultaneously their eye movements and posture. MATERIALS AND METHODS: Ninety-five healthy children from 5.8 to 17.6 years old were examined. All children were free of any vestibular, neurological, ophtalmologic and orthoptic abnormalities. Postural control was measured with a force platform TechnoConcept®, and eye movements with video oculography (MobilEBT®. Children performed two oculomotor tasks: fixation of a stable central target and horizontal saccades. We measured the saccade latency and the number of saccades during fixation as well as the surface, length and mean velocity of the center of pressure. RESULTS: During postural measurement, we observed a correlation between the age on the one hand and a decrease in saccade latency as well as an improvement in the quality of fixation on the other. Postural sway decreases with age and is reduced in the dual task (saccades in comparison with a simple task of fixation. DISCUSSION - CONCLUSION: These results suggest a maturation of neural circuits controlling posture and eye movements during childhood. This study also shows the presence of an interaction between the oculomotor system and the postural system. Engaging in oculomotor tasks results in a reduction of postural sway.

  11. Ethical issues related to biomonitoring studies on children

    DEFF Research Database (Denmark)

    Pedersen, Marie; Merlo, Domenico Franco; Knudsen, Lisbeth E.

    2007-01-01

    data respecting data protection including the right to know or not to know. Data protection is important because stakeholders may also ask for insight at various steps during human biomonitoring activities including children. Finally it is generally recommended that aim, methods, and results from...... biomonitoring studies should be communicated and study persons notified for further use of data and samples....

  12. Rorschach Responses of Sexually Abused Children: An Exploratory Study.

    Science.gov (United States)

    Clinton, Gregory T.; Jenkins-Monroe, Valata

    1994-01-01

    Using archival data, this study compared Rorschach protocols of 94 sexually abused children to the Exner norms in order to determine the potential usefulness of the Rorschach test in the area of child abuse assessment and treatment. Of the 18 Rorschach variables studied, 17 significantly distinguished at least one subject group from the norms.…

  13. CHILD DEVELOPMENT STUDY (NCDS): CHILDREN OF THE BRITISH NCDS

    Science.gov (United States)

    The National Child Development Study (NCDS) is one of Britain's birth cohort studies, surveying all the children born in U.K. in a week of March 1958 (a complete enumeration, not a sample). They have been re-interviewed several times over the past forty years: first, at the time ...

  14. Metabolic tracer studies with nitrogen-15 in children

    International Nuclear Information System (INIS)

    This paper reports the results of metabolic studies on children, performed using N-15 tracer techniques. Separate experiments described address studies of liver function, diagnosis of gastric Helicobacter pylori infections and investigations of the metabolic effects of recombinant human growth hormone on Turner Syndrome girls. 9 refs, 8 figs

  15. Commercial vs. product placement: A study with young children

    OpenAIRE

    Omar, Ismael Mahomed

    2010-01-01

    A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics The aim of this study is to investigate how young children (5-7 years old) are affected by commercials and product placements regarding the detection of advertising content, brand awareness and brand choice. We also wanted to study the relation of those variables with age (children before and after entering into primary school) and gender. F...

  16. Roentgen study of bone age in obese children

    International Nuclear Information System (INIS)

    The study included 100 children (50 boys and 50 girls) aged from 1 to 18 years with different degree of obesity, classified according to the scheme of Knyazev et al. The bone age was determined by a X-ray method including conventional X-ray study of the left hand at standard conditions. The H. Thiemann - I. Nittz Atlass (1986) was used as a test. It was established that the children with overweight had a change in the bone age which in most cases outstriped the calendar one. It was stated that the determination of the index 'bone age' remained to be a reliable method for studing the obesity effect on the growth and developing of the children' organism. 2 figs., 2 tabs., 12 refs

  17. Preliminary study of the charged particle radiaton for th satellite power system

    International Nuclear Information System (INIS)

    A preliminary radiation study was performed for the SPS project in order to determine the energetic charged particle environment for the three major phases of an SPS mission: the low earth orbit (LEO), the transfer ellipse (TE), and the synchronous geostationary trajectory (GEO). For that purpose, extensive calculations were performed and a large data base was generated, processeed, and analyzed. The external (surface incident) charged particle intensities, predicted for the SPS in each mission phase, were determined by orbital flux integration from the latest environment models. Magnetic field definitions for the three trajectories were obtained from a current field model. Spatial and temporal variations or conditions were considered and accounted for, where possible. Limited shielding and dose evaluations were performed for a simple geometry. The results of this analysis are presented in tabular and graphical form

  18. Studying electromagnetic interference spectrum in antenna under aircraft radome using models with artificial charged aerosol clouds

    Science.gov (United States)

    Temnikov, A. G.; Gilyazov, M. Z.; Matveev, D. A.; Voronkova, A. Yu.; Chernenskii, L. L.; Orlov, A. V.

    2011-09-01

    The spectrum of electromagnetic interference that is induced by discharges in an antenna arranged under an aircraft radome in an artificial charged aqueous aerosol cloud has been experimentally studied. It is established that, among different possible variants of lightning-arrest radomes, the minimum level of the spectral density of interference signals in the antenna is provided by vertical stripe electrodes on the radome surface. The maximum characteristic frequencies of signals in a model spherical antenna are several times lower than those in model lightning diverters, while the flat model antennas of disk or rectangular shapes exhibit the opposite trend. It has been suggested that a significant role in determining the characteristics of the electromagnetic interference spectrum in weather radar antennas is played by currents of discharges generated by charges accumulated on the dielectric radome surface.

  19. A scanning Kelvin probe study of charge trapping in zone-cast pentacene thin film transistors

    International Nuclear Information System (INIS)

    We have used scanning Kelvin probe microscopy (SKPM) as a local probe to study charge trapping in zone-cast pentacene field effect transistors on both SiO2 and benzocyclobutene (BCB) substrates. Annealing at 130 deg. C was found to reduce the threshold voltage, susceptibility to negative gate bias stress and trapping of positive charges within single pentacene grains. We conclude that oxygen is able to penetrate and disassociatively incorporate into crystalline pentacene, chemically creating electrically active defect states. Screening of a positive gate bias caused by electron injection from Au into pentacene was directly observed with SKPM. The rate of screening was found to change significantly after annealing of the film and depended on the choice of gate dielectric.

  20. Fundamental Studies of Charge Migration and Delocalization Relevant to Solar Energy Conversion

    Energy Technology Data Exchange (ETDEWEB)

    Michael J. Therien

    2012-06-01

    This program aimed to understand the molecular-level principles by which complex chemical systems carry out photochemical charge separation, transport, and storage, and how these insights could impact the design of practical solar energy conversion and storage devices. Towards these goals, this program focused on: (1) carrying out fundamental mechanistic and transient dynamical studies of proton-coupled electron-transfer (PCET) reactions; (2) characterizing and interrogating via electron paramagnetic resonance (EPR) spectroscopic methods novel conjugated materials that feature large charge delocalization lengths; and (3) exploring excitation delocalization and migration, as well as polaron transport properties of meso-scale assemblies that are capable of segregating light-harvesting antennae, nanoscale wire-like conduction elements, and distinct oxidizing and reducing environments.

  1. Numerical Study of Three Dimensional Effects in Longitudinal Space-Charge Impedance

    Energy Technology Data Exchange (ETDEWEB)

    Halavanau, A. [NICADD, DeKalb; Piot, P. [NICADD, DeKalb

    2015-06-01

    Longitudinal space-charge (LSC) effects are generally considered as detrimental in free-electron lasers as they can seed instabilities. Such “microbunching instabilities” were recently shown to be potentially useful to support the generation of broadband coherent radiation pulses [1, 2]. Therefore there has been an increasing interest in devising accelerator beamlines capable of sustaining this LSC instability as a mechanism to produce a coherent light source. To date most of these studies have been carried out with a one-dimensional impedance model for the LSC. In this paper we use a N-body “Barnes-Hut” algorithm [3] to simulate the 3D space charge force in the beam combined with elegant [4] and explore the limitation of the 1D model often used

  2. Telescope for studying charged particles produced by 14 MeV neutrons

    International Nuclear Information System (INIS)

    We have developed a telescope using semi-conductor detectors for studying the charged particles produced in a thin radiator by 14 MeV neutrons. It consists of a proportional CO2-counter and two cooled semiconductor detectors (one of the ΔE/ΔX type, the other of the E type). This low-noise telescope has good energy resolution (370 keV). Used in conjunction with a bi-parametric recording (ΔE - E) it gives a satisfactory identification and discrimination of the charged particles (p,d) detected. This telescope has been used to observe the spectrum of protons from the reaction D(n,p)2n emitted at 0 deg. (En 13.9 MeV) in the energy range 4 - 14 MeV. (author)

  3. Electron capture rates in stars studied with heavy ion charge exchange reactions

    CERN Document Server

    Bertulani, C A

    2015-01-01

    Indirect methods using nucleus-nucleus reactions at high energies (here, high energies mean $\\sim$ 50 MeV/nucleon and higher) are now routinely used to extract information of interest for nuclear astrophysics. This is of extreme relevance as many of the nuclei involved in stellar evolution are short-lived. Therefore, indirect methods became the focus of recent studies carried out in major nuclear physics facilities. Among such methods, heavy ion charge exchange is thought to be a useful tool to infer Gamow-Teller matrix elements needed to describe electron capture rates in stars and also double beta-decay experiments. In this short review, I provide a theoretical guidance based on a simple reaction model for charge exchange reactions.

  4. Theoretical study on photoproduction of the charged charmoniumlike $Z_{c}^{+}(4200)$

    CERN Document Server

    Wang, Xiao-Yun

    2015-01-01

    In this work, inspired by the observation of charmoniumlike $Z_{c}^{+}(4200)$%, we study the photoproduction of the charged charmoniumlike $Z_{c}^{+}(4200) $ with an effective Lagrangian approach and the Regge trajectories model. The numerical results indicate that the Reggeized treatment can lead to a lower total cross section of the $Z_{c}^{+}(4200)$ photoproduction and the peak position of cross section was moved to the higher energy point when using the Reggeized treatment. Also discussed is the feasibility of searching for the charged charmoniumlike $Z_{c}^{+}(4200)$. The relevant results not only shed light on the further experiment of searching for the charmoniumlike $Z_{c}(4200)$ state via meson photoproduction, but also provide valuable informations for having a better comprehension of properties and producing mechanism of charmoniumlike $Z_{c}(4200)$ state.

  5. Pushing X-ray charge densities to the limit: Comparative study of CoSb3

    DEFF Research Database (Denmark)

    Schmøkel, Mette Stokkebro; Larsen, Finn Krebs; Overgaard, Jacob; Bjerg, Lasse; Cenedese, Simone; Jørgensen, Mads Ry Vogel; Christensen, Mogens; Iversen, Bo Brummerstedt

    CoSb3 is a highly important host-guest material for the engineering of high-performance thermoelectric materials.[1] Its crystal structure has empty cavities and when guest atoms are added to CoSb3, its thermoelectric properties are greatly enhanced due to decreased thermal conductivity.[2] In...... order to understand the origin of the thermoelectric properties of this family of materials, it is important to understand the crystal structure and chemical bonding of the un-doped host material.[3] This can be achieved through analysis of the charge density, which in principle can be obtained from...... modeling of accurate X-ray diffraction data.[4] However, considering the heavy elements, the high symmetry and the perfect crystallinity of this inorganic network structure one cannot think of a much more challenging case for experimental charge density analysis. In the present study we analyze several low...

  6. Nanoscale charge transport in cytochrome c3/DNA network: Comparative studies between redox-active molecules

    Science.gov (United States)

    Yamaguchi, Harumasa; Che, Dock-Chil; Hirano, Yoshiaki; Suzuki, Masayuki; Higuchi, Yoshiki; Matsumoto, Takuya

    2015-09-01

    The redox-active molecule of a cytochrome c3/DNA network exhibits nonlinear current-voltage (I-V) characteristics with a threshold bias voltage at low temperature and zero-bias conductance at room temperature. I-V curves for the cytochrome c3/DNA network are well matched with the Coulomb blockade network model. Comparative studies of the Mn12 cluster, cytochrome c, and cytochrome c3, which have a wide variety of redox potentials, indicate no difference in charge transport, which suggests that the conduction mechanism is not directly related to the redox states. The charge transport mechanism has been discussed in terms of the newly-formed electronic energy states near the Fermi level, induced by the ionic interaction between redox-active molecules with the DNA network.

  7. Reaction mechanism and nuclear correlations study by low energy pion double charge exchange

    International Nuclear Information System (INIS)

    In pion double-charge-exchange (DCX) reactions, a positive (negative) pion is incident on a nucleus and a negative (positive) pion emerges. These reactions are of fundamental interest since the process must involve at least two nucleons in order to conserve charge. Although two nucleon processes are present in many reactions they are usually masked by the dominant single nucleon processes. DCX is unique in that respect since it is a two nucleon process in lowest order and thus may be sensitive to two-nucleon correlations. Measurements of low energy pion double-charge-exchange reactions to the double-isobaric-analog-state (DIAS) and ground-state (GS) of the residual nucleus provide new means for studying nucleon-nucleon correlations in nuclei. At low energies (Tπ 7/2 shell at energies ranging from 25 to 65 MeV. Cross sections were measured on 42,44,48Ca, 46,50Ti and 54Fe. The calcium isotopes make a good set of nuclei on which to study the effects of correlations in DCX reactions

  8. Theoretical Study on Charge Transport Properties of Intra- and Extra-Ring Substituted Pentacene Derivatives.

    Science.gov (United States)

    Fan, Jian-Xun; Chen, Xian-Kai; Zhang, Shou-Feng; Ren, Ai-Min

    2016-04-21

    A series of pentacene derivatives, halogen-substituted and thiophene- and pyridine-substituted, have been studied with a focus on the electronic properties and charge transport properties using density functional theory and classical Marcus charge-transfer theory. The transport properties of holes and electrons have been studied to get insight into the effect of halogenation and heteroatom substitution on transport and injection of charge carriers. The calculation results revealed that fluorination and chlorination can effectively lower the lowest unoccupied molecular orbital (LUMO) level, modulate the hole and electron reorganization energy, improve the stacking mode of the crystal structure, and enhance the ambipolar characteristic. Chlorination gives a better ambipolar characteristic. On the basis of halogen substitution, the substitution of terminal benzene ring of triisopropyl-silylethynyl-pentacene (TIPS-PEN) by a thiophene or pyridine will greatly lower the LUMO level and improve the stacking mode, leading to more suitable ambipolar materials. Hence, both intra- and extra-ring substitution are favorable to enhance the ambipolar transport property of TIPS-PEN. PMID:27027319

  9. Age Effects in a Study Abroad Context: Children and Adults Studying Abroad and at Home

    Science.gov (United States)

    Llanes, Angels; Munoz, Carmen

    2013-01-01

    This study examines the effects of learning context and age on second language development by comparing the language gains, measured in terms of oral and written fluency, lexical and syntactic complexity, and accuracy, experienced by four groups of learners of English: children in a study abroad setting, children in their at-home school, adults in…

  10. Low-Energy Charge Transfer in Multiply-Charged Ion-Atom Collisions Studied with the Combined SCVB-MOCC Approach

    Directory of Open Access Journals (Sweden)

    B. Zygelman

    2002-03-01

    Full Text Available A survey of theoretical studies of charge transfer involving collisions of multiply-charged ions with atomic neutrals (H and He is presented. The calculations utilized the quantum-mechanical molecular-orbital close-coupling (MOCC approach where the requisite potential curves and coupling matrix elements have been obtained with the spin-coupled valence bond (SCVB method. Comparison is made among various collision partners, for equicharged systems, where it is illustrated that even for total charge transfer cross sections, scaling-laws do not exist for low-energy collisions (i.e. < 1 keV/amu. While various empirical scaling-laws are well known in the intermediateand high-energy regimes, the multi-electron configurations of the projectile ions results in a rich and varied low-energy dependence, requiring an explicit calculation for each collision-partner pair. Future charge transfer problems to be addressed with the combined SCVB-MOCC approach are briefly discussed.

  11. Air pollution and respiratory health of children: the PEACE panel study in Umea., Sweden.

    NARCIS (Netherlands)

    Forsberg, B.; Segerstedt, B.; Stjernberg, N.; Roemer, W.

    1998-01-01

    The Pollution Effects on Asthmatic Children in Europe (PEACE) study examined the acute effects of short-term changes in air pollution on symptomatic children. We were one of 14 research centres in Europe that used a common study protocol. Seventy five children in an urban panel and 72 children in a

  12. A Population-Based Longitudinal Study of Depression in Children with Developmental Disabilities in Manitoba

    Science.gov (United States)

    Shooshtari, Shahin; Brownell, Marni; Dik, Natalia; Chateau, Dan; Yu, C. T.; Mills, Rosemary S. L.; Burchill, Charles A.; Wetzel, Monika

    2014-01-01

    In this population-based study, prevalence of depression was estimated and compared between children with and without developmental disability (DD). Twelve years of administrative data were linked to identify a cohort of children with DD living in the Canadian province of Manitoba. Children in the study cohort were matched with children without DD…

  13. Children's Experiences and Meaning Construction on Parental Divorce: A Focus Group Study

    Science.gov (United States)

    Maes, Sofie D. J.; De Mol, Jan; Buysse, Ann

    2012-01-01

    The global aim of this study was to explore children's narratives of parental divorce. A convenience sample, composed of 11- and 14-year-old children, was recruited. A total of 22 children (12 male, 10 female) participated in this focus group study. The findings show that two components seem to be really important for children during the divorce…

  14. Environment and Obesity in the National Children's Study Ambiente e obesidade no National Children's Study

    Directory of Open Access Journals (Sweden)

    Leonardo Trasande

    2010-01-01

    Full Text Available We describe the approach taken by the National Children's Study (NCS to understanding the role of environmental factors in the development of obesity. We review the literature with regard to the two core hypotheses in the NCS that relate to environmental origins of obesity and describe strategies that will be used to test each hypothesis. Although it is clear that obesity in an individual results from an imbalance between energy intake and expenditure, control of the obesity epidemic will require understanding of factors in the modern built environment and chemical exposures that may have the capacity to disrupt the link between energy intake and expenditure. Through its embrace of the life-course approach to epidemiology, the NCS will be able to study the origins of obesity from preconception through late adolescence, including factors ranging from genetic inheritance to individual behaviors to the social, built, and natural environment and chemical exposures. It will have sufficient statistical power to examine interactions among these multiple influences, including geneenvironment and geneobesity interactions. A major secondary benefit will derive from the banking of specimens for future analysis.Descrevemos a abordagem do National Children's Study (NCS para entender o papel dos fatores ambientais no desenvolvimento da obesidade. Revisamos a literatura a respeito de duas hipóteses principais no NCS que se relacionam a origens ambientais da obesidade e descrevem estratégias que serão utilizadas para testar cada hipótese. Apesar de estar claro que a obesidade em um indivíduo é resultado de um desequilíbrio entre consumo e gasto de energia, o controle da epidemia de obesidade requer o entendimento de fatores no ambiente moderno e exposições químicas que podem ter a capacidade de interromper a ligação entre o consumo e gasto de energia. Através da aceitação da abordagem do curso de vida a epidemiologia, o NCS será capaz de estudar

  15. Study of a ring-effect ions generator efficiency. Application to the charge and the neutralization of an aerosol cloud

    International Nuclear Information System (INIS)

    The knowledge of the aerosols electric charge is fundamental in the aerosols technology. The aerosols win an electric charge during their generation or in presence of a ionized medium. Facing the regulation hardening in matter of radioactive sources, the author developed a ring-effect ions generator. Tis study presents the first experimental results and discusses the generator performances. (A.L.B.)

  16. Children and Clinical Studies: Why Clinical Studies Are Important

    Medline Plus

    Full Text Available U.S. Department of Health & Human Services National Institutes of Health Contact Us Get Email Alerts Font Size Accessible Search ... Health Topics Education & Awareness Resources Contact The Health Information Center ... Transfer Clinical Trials What Are Clinical Trials? Children & ...

  17. Children and Clinical Studies: Why Clinical Studies Are Important

    Medline Plus

    Full Text Available ... Entire Site Health Topics News & Resources Intramural Research Public Health Topics Education & Awareness Resources Contact The Health Information ... for parents, clinicians, researchers, children, and the general public. Last Updated: August 3, 2015 Resources Educational Website - English / ... Facebook Page

  18. A STUDY ON PREVALENCE OF REFRACTIVE ERRORS IN SCHOOL CHILDREN

    Directory of Open Access Journals (Sweden)

    Kolli Sree Karuna

    2014-08-01

    Full Text Available ‘’Sarvendriya nam nayanam pradhanam” Of all the organs in the body, eyes are the most important. The blindness or defect in vision decreases the productivity of the nation in addition to increased dependability. The refractive errors in the school children throw them in to defective future. Nutrition deficiency, mental strain, wrong reading habits etc are some of the causes for this defect in these children. Vision is essential for all the children, for the academic and overall development of the now children who are the future Indian Citizens. An attempt was made to study the prevalence of refractive errors in school children. The Lions clubs International has come forward to present the spectacles to all the needy children to correct the refractive errors. MATERIALS & METHODS: By Quantitative method--History taking from all the students by questionnaire method using a preformed structural format and all the visual acuity was clinically examined thoroughly using Snellen’s chart, pinhole occlude for all the students. Colour vision was also tested using Ishihara chart.500 students participated in cross sectional study. The results were analyzed using Microsoft excel. 21.4% eat carrot daily, 15.9% eat weekly one, 20.2% eat weekly twice, 27.1% eat monthly once, 23.8% eat monthly twice, and 26.4% do not eat carrot at all. Defective vision is more prevalent in children eating carrot once in a month. 6.7% eat green leafy vegetables daily, 21% eat weekly once, 21.9% eat weekly twice, 13.6% eat monthly once, 27.3% eat monthly twice, and 33.3% do not eat at all. Defective vision is more common in children who do not eat green leafy vegetables at all.19.9% eat fruits daily, 24.9% eat weekly once, 21.3% eat weekly twice, 20% eat monthly once, 6.7% eat monthly twice and the remaining 50% do not eat fruits at all. Defective vision is more common in children who do not eat fruits at all. All the students with refractive errors were provided with

  19. Glitz childhood: a study on the charges of beauty contests to children’s bodies

    OpenAIRE

    Rafaela da Silva Melo; Rosangela de Fátima Rodrigues Soares

    2014-01-01

    From the excerpts of episodes of the reality show Toddlers and Tiaras and the contributions of childhood studies and post-structuralist theoretical perspective, I try to analyze the discourses of "truth" that support the need for radical transformation of children's bodies to meet the requirements of beauty contests. Discourses that have served as justification for contemporary forms of exploitation, abuse, discipline and government of infant bodies

  20. The Oncogenic Risks of Diagnostic CT Scam Studies in Children

    Energy Technology Data Exchange (ETDEWEB)

    Brent, R.

    2004-07-01

    Brenner et al (2001) reported that estimates of the exposure to children from CT scans indicates that the exposures are both higher than from conventional radiographic studies and higher than is necessary to obtain quality examinations. utilizing the oncogenic risk data from the RERF study in Japan, Brenner et al estimated that the oncogenic risk in this population of CT exposed children exposed each year would result in an additional 500 cases of cancer. This risk estimate is supported by the RERF epidemiological data obtained from the populations exposed in Hiroshima and Nagasaki. the increased risks associated with the increased exposure from CT scans have raised concern and stimulated discussion. Although there is little doubt about the benefits of CT scans in improving the health care of children, there is concern about the estimated oncogenic risk, especially since the frequency of CT studies has been increasing. Applying the oncogenic risks of ionizing radiation from the RERF data may not be appropriate for all types of radiation exposure for accurately predicting the incidence of cancer in exposed children because of the impact of 1) partial versus whole-body irradiation, and 2) the protraction of the exposure. Other population of children who have been exposed to radiation and whose incidence of cancer has been studied will be presented and those studies indicate that the risk of cancer is much lower or not increased at all with exposures in the diagnostic range. finally, the dramatic impact of the use of CT scans in clinical pediatric practice saves lives and improves diagnostic accuracy. Therefore, it is crucial that a scholarly evaluation of the risks and benefits should be initiated. The radiology community and the manufacturers have already initiated programs to decrease the exposure significantly. But it is essential that well-planned, retrospective and prospective epidemiology studies should be initiated to study the oncogenic risks. If you want to

  1. Preliminary study for the detection of neutrons in heavy-ion collisions with charged particle detectors

    Directory of Open Access Journals (Sweden)

    Auditore L.

    2015-01-01

    Full Text Available At Laboratori Nazionali del Sud (LNS the CHIMERA 4π multidetector has been designed and setup to detect charged particles emitted in heavy ion collisions at intermediate energies. Properties and performances of CHIMERA have been widely demonstrated by published results obtained in the performed experiments. Moreover, in recent years, a new charged particle detector (ChPD for correlation studies (FARCOS has been designed, and recently a first prototype has been coupled to CHIMERA, in order to test performances in view of correlation measurements in coincidence with 4π detectors. Simultaneous neutrons and charged particles detection in heavy ion collisions represents an important experimental progress for future experiments to be performed with both stable and exotic nuclei. In order to investigate about this possibility, simple Monte Carlo simulations have been performed. Preliminary simulations have been carried out by means of MCNPX transport code to evaluate the perturbation effects, including cross-talk and time response, induced in CHIMERA and/or FARCOS Si-CsI(Tl telescopes on (typical 20MeV neutron signals coming froma typical reaction in heavy ion collisions at the Fermi energy. Moreover, first data analysis results of the INKIISSY experiment indicates sizable probability to detect neutrons by properly shadowing CHIMERA Si-CsI(Tl telescopes. Analysis is still in progress.

  2. Theoretical study of the hydrated Gd3+ ion: Structure, dynamics, and charge transfer

    Science.gov (United States)

    Clavaguéra, Carine; Calvo, Florent; Dognon, Jean-Pierre

    2006-02-01

    The dynamical processes taking place in the first coordination shells of the gadolinium (III) ion are important for improving the contrast agent efficiency in magnetic-resonance imaging. An extensive study of the gadolinium (III) ion solvated by a water cluster is reported, based on molecular dynamics simulations. The AMOEBA force field [P. Y. Ren and J. W. Ponder, J. Phys. Chem. B 107, 5933 (2003)] that includes many-body polarization effects is used to describe the interactions among water molecules, and is extended here to treat the interactions between them and the gadolinium ion. In this purpose accurate ab initio calculations have been performed on Gd3+-H2O for extracting the relevant parameters. Structural data of the first two coordination shells and some dynamical properties such as the water exchange rate between the first and second coordination shells are compared to available experimental results. We also investigate the charge transfer processes between the ion and its solvent, using a fluctuating charges model fitted to reproduce electronic structure calculations on [Gd(H2O)n]3+ complexes, with n ranging from 1 to 8. Charge transfer is seen to be significant (about one electron) and correlated with the instantaneous coordination of the ion.

  3. Studies on space charge neutralization and emittance measurement of beam from microwave ion source

    International Nuclear Information System (INIS)

    A 2.45 GHz microwave ion source together with a beam transport system has been developed at VECC to study the problems related with the injection of high current beam into a compact cyclotron. This paper presents the results of beam profile measurement of high current proton beam at different degrees of space charge neutralisation with the introduction of neon gas in the beam line using a fine leak valve. The beam profiles have been measured at different pressures in the beam line by capturing the residual gas fluorescence using a CCD camera. It has been found that with space charge compensation at the present current level (∼5 mA at 75 keV), it is possible to reduce the beam spot size by ∼34%. We have measured the variation of beam profile as a function of the current in the solenoid magnet under the neutralised condition and used these data to estimate the rms emittance of the beam. Simulations performed using equivalent Kapchinsky-Vladimirsky beam envelope equations with space charge neutralization factor are also presented to interpret the experimental results

  4. Thermal Charging Study of Compressed Expanded Natural Graphite/Phase Change Material Composites

    Energy Technology Data Exchange (ETDEWEB)

    Mallow, Anne M [ORNL; Abdelaziz, Omar [ORNL; Graham, Samuel [Georgia Institute of Technology, Atlanta

    2016-01-01

    The thermal charging performance of phase change materials, specifically paraffin wax, combined with compressed expanded natural graphite foam is studied under constant heat flux and constant temperature conditions. By varying the heat flux between 0.39 W/cm2 and 1.55 W/cm2 or maintaining a boundary temperature of 60 C for four graphite foam bulk densities, the impact on the rate of thermal energy storage is discussed. Thermal charging experiments indicate that thermal conductivity of the composite is an insufficient metric to compare the influence of graphite foam on the rate of thermal energy storage of the PCM composite. By dividing the latent heat of the composite by the time to melt for various boundary conditions and graphite foam bulk densities, it is determined that bulk density selection is dependent on the applied boundary condition. A greater bulk density is advantageous for samples exposed to a constant temperature near the melting temperature as compared to constant heat flux conditions where a lower bulk density is adequate. Furthermore, the anisotropic nature of graphite foam bulk densities greater than 50 kg/m3 is shown to have an insignificant impact on the rate of thermal charging. These experimental results are used to validate a computational model for future use in the design of thermal batteries for waste heat recovery.

  5. Ion beam induced charge and numerical modeling study of novel detector devices for single ion implantation

    International Nuclear Information System (INIS)

    In the near future devices which are fabricated from shallow arrays of few and single atoms will exploit quantum mechanical rules to perform useful functions including quantum computation. Fabrication of these devices presents formidable technological challenges. We have developed a single ion implantation system that is capable of verifiable fabrication of single donor devices using 14 keV 31P ions implanted into ultra-pure, high resistivity silicon substrates based on the technique of Ion Beam Induced Charge (IBIC). A detection system with integrated detector electrodes registers the charge transient from a single ion impact which is used to signal the implantation of an ion into the substrate. We describe here the use of IBIC with MeV ions to study the charge collection efficiency of the detector electrodes. By using three dimensional numerical technology computer-aided design (TCAD) models for the decrease in the IBIC signal as a function of distance from the detector electrode, we can obtain an accurate measurement of the resistivity of the silicon substrate, allowing confirmation of the values specified by the supplier, and providing us with confidence in the numerical models used by TCAD for simulation. This technique has advantages over resistivity measurements by four-point probes because it is spatially resolved, probes through the intact oxide, and can be done without making contact to the device in the area of the probe

  6. Study of charged particle acceleration by magnetic reconnection in a plasma

    Directory of Open Access Journals (Sweden)

    M Mehdizade

    2016-02-01

    Full Text Available Magnetic reconnection, which occurs in high conducting plasmas, changes the topology of magnetic field lines and converts magnetic energy into the kinetic and thermal energy of plasma and also accelerates charged particles. This phenomenon plays an important role in changing the dynamic of laboratory and space plasmas such as fusion tokamaks and sun’s corona. The electric and magnetic fields generated by magnetic reconnection result in acceleration and drift motion of charged particles. Therefore, charged particles, depending on their injection position and initial kinetic energy, can be accelerated and escape or can be trapped in magnetic fields. In this study by considering different injection positions and initial kinetic energies, we investigate how a particle (proton is accelerated or trapped. Our numerical analyses show that the spine structure for three-dimensional magnetic reconnection can be considered as a potential mechanism for particle acceleration. In this model, a proton can be accelerated up to a few MeV within a few milliseconds. The particle’s trajectory and final kinetic energy strongly depend on its injection position.

  7. Study of proton polarization in charge exchange process on optically oriented sodium atoms

    International Nuclear Information System (INIS)

    Using high-power adjustable dye lasers for electron spin orientation in a charge-exchange target enables to significantly increase the proton polarization efficiency. A device is described that permits to avoid growth of the polarized proton beam emittance in a charge-exchange process in a strong magnetic field. The devise main feature is the use of an intensive source of neutral hydrogen atoms and the presence of a helium additional charge-exchange target which actualy is a proton ''source''. The helium charge-exchange cell is placed in the same magnetic field of a solenoid where a cell with oriented sodium is placed, a polarized electron being captured by a proton in the latter cell. In this case the beam at the solenoid inlet and outlet is in a neutral state; emittance growth related to the effect of end magnetic fields is not observed. The device after all prouduces polarized protons, their polarization degree is measured and the effect of various factors on polarization degree is studied. The description of the laser source and laser system is given. Measurement results have shown the beam intensity of neutral 7 keV atoms which passed through a polarizer to be 2 mA. The proton current doesn't depend. On the beeld fin the region of chrge exchange for the 8 kGs magnetic field. The degree of sodium polarization was 80% and polarized proton current approximately 70 μA at a temperature of the polarized sodium cell corresponding to the density of sodium vapar approximately 3x1013 at/cm2

  8. Charged defects in chalcogenide vitreous semiconductors studied with combined Raman scattering and PALS methods

    International Nuclear Information System (INIS)

    A combination of Raman scattering and positron annihilation lifetime spectroscopy (PALS) techniques to study charged defects in chalcogenide vitreous semiconductors (ChVSs) was applied for the first time in this study. In the case of Ge15.8As21S63.2 glass, it is found that the main radiation-induced switching of heteropolar Ge-S bonds into heteropolar As-S ones, previously detected by IR fast Fourier transform spectroscopy, can also be identified by Raman spectroscopy in the depolarized configuration. Results obtained by Raman scattering are in good agreement with PALS data for the investigated glass composition

  9. Charged defects in chalcogenide vitreous semiconductors studied with combined Raman scattering and PALS methods

    Energy Technology Data Exchange (ETDEWEB)

    Kavetskyy, T.; Vakiv, M. [Lviv Institute of Materials of SRC ' Carat' , 202 Stryjska str., Lviv, UA-79031 (Ukraine); Shpotyuk, O. [Lviv Institute of Materials of SRC ' Carat' , 202 Stryjska str., Lviv, UA-79031 (Ukraine)], E-mail: shpotyuk@novas.lviv.ua

    2007-04-15

    A combination of Raman scattering and positron annihilation lifetime spectroscopy (PALS) techniques to study charged defects in chalcogenide vitreous semiconductors (ChVSs) was applied for the first time in this study. In the case of Ge{sub 15.8}As{sub 21}S{sub 63.2} glass, it is found that the main radiation-induced switching of heteropolar Ge-S bonds into heteropolar As-S ones, previously detected by IR fast Fourier transform spectroscopy, can also be identified by Raman spectroscopy in the depolarized configuration. Results obtained by Raman scattering are in good agreement with PALS data for the investigated glass composition.

  10. Radiation exposure from nuclear medicine studies in children

    International Nuclear Information System (INIS)

    Nuclear medical examinations of children have to be performed with special regard to the problems of radiation protection because of the high radiation sensitivity esp. of infants and young children. The present contribution describes how any unnecessary radiation exposure can be avoided by the correct choice and planning of a nuclear medical study, by using the appropriate radiopharmaceutical as well as by the exact calculation of the amount of activity applied, depending on body surface resp. body weight of the child. A technically optimized method which employs the best technical equipment and personnel, being specially trained for working with children, are important conditions to achieve optimal results of nuclear medical tests. Due to the difficulties of direct dose measurements, large variations in the biokinetic behaviour of radiopharmaceuticals and the restriction to standard phantoms, individual dose calculations or dose estimations in pediatrics cause great problems. This is reflected by often large variations of dosimetrical data given in the literature. (orig.)

  11. STUDY OF OVARIAN LESIONS IN CHILDREN

    OpenAIRE

    Nagarjuna; Srinivas,; Ramesh Reddy; Lavanya; Inugala

    2015-01-01

    : AIM: To study ovarian lesions in paediatric patients. MATERIALS AND METHODS: All cases of ovarian lesions presenting to Niloufer Hospital during the study period spanning 7 years were included in the study. All cases were clinically examined and evaluated with serum markers like α-fetoprotein and β-HCG, ultrasonography of abdomen and pelvis and contrast enhanced computed tomography of abdomen and pelvis. The cases were managed either conservatively or surgically depending on...

  12. Chronic nonbacterial osteomyelitis in children: a retrospective multicenter study

    OpenAIRE

    Kaiser, Daniela; Bolt, Isabel; Hofer, Michael; Relly, Christa; Berthet, Gerald; Bolz, Dieter; Saurenmann, Traudel

    2015-01-01

    Background To determine the clinical presentation, current treatment and outcome of children with nonbacterial inflammatory bone disease. Methods Retrospective multicenter study of patients entered into the Swiss Pediatric Rheumatology Working Group registry with a diagnosis of chronic nonbacterial osteomyelitis (CNO) and synovitis acne pustulosis hyperostosis osteitis (SAPHO) syndrome. The charts were reviewed for informations about disease presentation, treatment, course and outcome. Result...

  13. Chronic nonbacterial osteomyelitis in children: a retrospective multicenter study

    OpenAIRE

    Kaiser, Daniela; Bolt, Isabel; Hofer, Michael; Relly, Christa; Berthet, Gerald; Bolz, Dieter; Saurenmann, Traudel

    2015-01-01

    BACKGROUND: To determine the clinical presentation, current treatment and outcome of children with nonbacterial inflammatory bone disease. METHODS: Retrospective multicenter study of patients entered into the Swiss Pediatric Rheumatology Working Group registry with a diagnosis of chronic nonbacterial osteomyelitis (CNO) and synovitis acne pustulosis hyperostosis osteitis (SAPHO) syndrome. The charts were reviewed for informations about disease presentation, treatment, course and outcome. ...

  14. A Study in Training Nursery Children on Logical Operational Skills.

    Science.gov (United States)

    Kincaid, Carolyn; And Others

    Piaget's organismic-developmental theory of intelligence was investigated in this study to determine the effectiveness of training middle class 3 and 4 year olds on two logico-mathematical structures: classification and seriation. Twenty-four children were divided into two main age groups (mean ages: 3 years 8 months; 4 years 5 months). Within…

  15. Speech Sound Disorders in a Community Study of Preschool Children

    Science.gov (United States)

    McLeod, Sharynne; Harrison, Linda J.; McAllister, Lindy; McCormack, Jane

    2013-01-01

    Purpose: To undertake a community (nonclinical) study to describe the speech of preschool children who had been identified by parents/teachers as having difficulties "talking and making speech sounds" and compare the speech characteristics of those who had and had not accessed the services of a speech-language pathologist (SLP). Method:…

  16. Diagnostics of children's school readiness in scientific studies abroad

    Directory of Open Access Journals (Sweden)

    Nazarenko V.V.

    2012-06-01

    Full Text Available The article considers the problem of children's school readiness as it is represented in contemporary studies of foreign scholars. It displays a variety of approaches to estimation of school readiness as well as the ways of measuring the levels of child development as relating to school readiness, namely those of them which are in common practice in education.

  17. Promoting Effective Interviewing of Sexually Abused Children: A Pilot Study

    Science.gov (United States)

    Cheung, Monit

    2008-01-01

    Objective: This study is centered on interviewing techniques with alleged child sexual abuse victims who do and do not disclose sexual abuse. Method: Ninety randomly selected videotapes are reviewed, and the interviewing techniques are recorded on a 69-item Child Sexual Abuse Interviewing Skills Instrument. Results: The nondisclosure children are…

  18. Observational Studies of Retarded Children with Multiple Stereotyped Movements.

    Science.gov (United States)

    Baumeister, Alfred A.; And Others

    1980-01-01

    Three relatively long-term observational studies, involving seven retarded preschool children, each of whom exhibited multiple stereotypes, were conducted to determine the extent to which the type of activity or setting had any effect upon the rates of stereotyped movements. (Author)

  19. Cholecystectomy in Danish children--a nationwide study

    DEFF Research Database (Denmark)

    Langballe, Karen Oline; Bardram, Linda

    2014-01-01

    into the secure Web site by the surgeon immediately after the operation. In the present analysis, we have included children ≤ 15 years from the five year period January 1, 2006, to December 31, 2010. RESULTS: In the study period 35,444 patients were operated with a cholecystectomy. Of these, 196 (0.5%) were ≤ 15...

  20. Environmental Influences on Children's Language: A Model and Case Study.

    Science.gov (United States)

    Hemmeter, Mary Louise; Kaiser, Ann P.

    1990-01-01

    This paper provides a conceptual model of the language learning environment of young children, incorporating child engagement with the physical environment, contributions of child and caregiver, and caregiver mediation of physical environment. A case study illustrates the impact of a relatively simple home environmental intervention on a…

  1. Use of SSRIs among Danish children: a nationwide study

    DEFF Research Database (Denmark)

    Pottegård, Anton; Zoega, H.; Hallas, J.;

    2014-01-01

    calculated as well as incidence rates and prevalence proportions. Furthermore, we looked at concurrent use of other psychotropic drug treatment duration. A total of 23,547 children aged 5-17 used SSRIs during the study period, most commonly sertraline followed by citalopram. Overall, the incidence rate...

  2. Metacognition and Control of Study Choice in Children

    Science.gov (United States)

    Metcalfe, Janet; Finn, Bridgid

    2013-01-01

    Middle childhood may be crucial for the development of metacognitive monitoring and study control processes. The first three experiments, using different materials, showed that Grade 3 and Grade 5 children exhibited excellent metacognitive resolution when asked to make delayed judgments of learning (JOLs, using an analogue scale) or binary…

  3. Understanding Insecure Attachment: A Study Using Children's Bird Nest Imagery

    Science.gov (United States)

    Sheller, Sandy

    2007-01-01

    This article describes a phenomenological study of the artistic creations of bird nests by four school-aged children to illuminate their internal experiences of attachment. The author analyzed qualitative data from in-depth interviews pertaining to two-dimensional and three-dimensional artistic representations of a bird's nest and a family of…

  4. Echotomography in the study of the uropathologic malformation in children

    International Nuclear Information System (INIS)

    The authors report on the usefulness of ultrasound in the study of uropathology malformations in children. They analize some caracteristic ecotomographic patterns of this pathology and emphasize validity and usefulness of the technique in diagnosis and the follow-up of these cases

  5. Children as Teachers: Developmental Studies of Instructional Communication

    Science.gov (United States)

    Pratt, Michael W.; And Others

    1977-01-01

    Two studies with elementary and preschool children investigated the effects of varying the perceptual support for speakers on the process of listener-adaptation in communication. An instructional task in which the child taught a peer to play a board game was utilized. (Author/JMB)

  6. Search for mutations altering protein charge and/or function in children of atomic bomb survivors: final report

    International Nuclear Information System (INIS)

    A sample of children whose parents were proximally exposed at the time of the atomic bombings of Hiroshima and Nagasaki (i.e., within 2,000 m of the hypocenter) and a suitable comparison group have been examined for the occurrence of mutations altering the electrophoretic mobility or activity of a series of 30 proteins. The examination of the equivalent of 667,404 locus products in the children of proximally exposed persons yielded three mutations altering electrophoretic mobility; the corresponding figure for the comparison group was three mutations in 466,881 tests. The examination of a subset of 60,529 locus products for loss of enzyme activity in the children of proximally exposed persons yielded one mutation; no mutations were encountered in 61,741 determinations on the children of the comparison group. Combining these two series, the mutation rate observed in the children of proximally exposed is thus 0.60 x 10-5/locus/generation, with 95 % confidence intervals between 0.2 and 1.5 x 10-5, and in the comparison children, 0.64 x 10-5/locus/generation, with 95 % intervals between 0.1 and 1.9 x 10-5. The average conjoint gonad doses of the proximally exposed parents are estimated to be 0.437 Gy of gamma radiation and 0.002 Gy of neutron radiation. Assigning a relative biological effectiveness of 20 to the neutron radiation, the combined total gonad dose of the parents becomes 0.477 Sv. (author)

  7. Search for mutations altering protein charge and/or function in children of atomic bomb survivors: final report

    International Nuclear Information System (INIS)

    A sample of (1) children whose parents had been proximally exposed (i.e., less than 2000 m from the hypocenter) at the time of the atomic bombings of Hiroshima and Nagasaki and (2) a suitable comparison group have been examined for the occurrence of mutations altering the electrophoretic mobility or activity of a series of 30 proteins. The examination of the equivalent of 667,404 locus products in the children of proximally exposed persons yielded three mutations altering electrophoretic mobility; the corresponding figure for the comparison group was three mutations in 466,881 tests. The examination of a subset of 60,529 locus products for loss of enzyme activity in the children of proximally exposed persons yielded one mutation; no mutations were encountered in 61,741 determinations on the children of the comparison group. When these two series are compared, the mutation rate observed in the children of proximally exposed persons is thus 0.60 x 10(-5)/locus/generation, with 95% confidence intervals between 0.2 and 1.5 x 10(-5), and that in the comparison children is 0.64 x 10(-5)/locus/generation, with 95% intervals between 0.1 and 1.9 x 10(-5). The average conjoint gonad doses for the proximally exposed parents are estimated to be 0.437 Gy of gamma radiation and 0.002 Gy of neutron radiation. If a relative biological effectiveness of 20 is assigned to the neutron radiation, the combined total gonad dose for the parents becomes 0.477 Sv. (Organ absorbed doses are expressed in gray [1 Gy = 100 rad]; where dose is a mixture of gamma and neutron radiation, it is necessary because of the differing relative biological effectiveness of gamma and neutron radiation to express the combined gamma-neutron gonad exposures in sieverts [1 Sv = 100 rem])

  8. Reliability of bioimpedance analysis compared with other adiposity measurements in children: the FLVS II Study. : Bioimpedance fat measurement in children

    OpenAIRE

    Kettaneh, Adrien; Heude, Barbara; Lommez, Agnès; Borys, Jean-Michel; Ducimetière, Pierre; Charles, Marie-Aline

    2005-01-01

    OBJECTIVE: To evaluate the reproducibility of the measurement of% body fat by bipedal biometrical impedance analysis (BIA) compared with anthropometric measurements of adiposity in children and the correlations between these methods in children and adults.METHODS: A cross-sectional study in a total of 1080 adults and children enrolled in 1999 in the Fleurbaix-Laventie Ville Sant?I (FLVS II) population-based study in northern France. The reproducibility of anthropometrical and BIA methods was ...

  9. Design and studies on supramolecular ferrocene-porphyrin-fullerene constructs for generating long-lived charge separated states.

    Science.gov (United States)

    D'Souza, Francis; Chitta, Raghu; Gadde, Suresh; Islam, D-M Shafiqul; Schumacher, Amy L; Zandler, Melvin E; Araki, Yasuyuki; Ito, Osamu

    2006-12-21

    Supramolecular ferrocene-porphyrin-fullerene constructs, in which covalently linked ferrocene-porphyrin-crown ether compounds were self-assembled with alkylammonium cation functionalized fullerenes, have been designed to achieve stepwise electron transfer and hole shift to generate long-lived charge separated states. The adopted crown ether-alkylammonium cation binding strategy resulted in stable conjugates as revealed by computational studies performed by the DFT B3LYP/3-21G(*) method in addition to the binding constants obtained from fluorescence quenching studies. The free-energy changes for charge-separation and charge-recombination were varied by the choice of different metal ions in the porphyrin cavity. Free-energy calculations suggested that the light-induced electron-transfer processes from the singlet excited state of porphyrins to be exothermic in all of the investigated supramolecular dyads and triads. Photoinduced charge-separation and charge-recombination processes have been confirmed by the combination of the time-resolved fluorescence and nanosecond transient absorption spectral measurements. In case of the triads, the charge-recombination processes of the radical anion of the fullerene moiety take place in two steps, viz., a direct charge recombination from the porphyrin cation radical and a slower step involving distant charge recombination from the ferrocene cation moiety. The rates of charge recombination for the second route were found to be an order of magnitude slower than the former route, thus fulfilling the condition for charge migration to generate long-lived charge-separated states in supramolecular systems. PMID:17165968

  10. Search for mutations altering protein charge and/or function in children of atomic bomb survivors: final report.

    OpenAIRE

    Neel, J V; Satoh, C; Goriki, K; Asakawa, J; M Fujita; Takahashi, N.; Kageoka, T; Hazama, R.(Research Center for Nuclear Physics and Department of Physics, Osaka University, Ibaraki, Osaka 567-0047, Japan)

    1988-01-01

    A sample of (1) children whose parents had been proximally exposed (i.e., less than 2,000 m from the hypocenter) at the time of the atomic bombings of Hiroshima and Nagasaki and (2) a suitable comparison group have been examined for the occurrence of mutations altering the electrophoretic mobility or activity of a series of 30 proteins. The examination of the equivalent of 667,404 locus products in the children of proximally exposed persons yielded three mutations altering electrophoretic mob...

  11. Study regarding Primary Obesity in the Case of Children

    OpenAIRE

    Antoanela GIOSAN

    2012-01-01

    Obesity, that is the increase of corporal weight for the adipose tissue, became one of the most encountered nutrition-related diseases. The author attempts in the study the dissemination of observations accumulated following a clinical-statistical study regarding obesity and overweight at the pre-school children from six Romanian kindergartens. The main objectives pursued are the nutrition habits and the level of physical activity. The modality used for the study is the statistical inquiry.

  12. Study on the Optimal Charging Strategy for Lithium-Ion Batteries Used in Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Shuo Zhang

    2014-10-01

    Full Text Available The charging method of lithium-ion batteries used in electric vehicles (EVs significantly affects its commercial application. This paper aims to make three contributions to the existing literature. (1 In order to achieve an efficient charging strategy for lithium-ion batteries with shorter charging time and lower charring loss, the trade-off problem between charging loss and charging time has been analyzed in details through the dynamic programing (DP optimization algorithm; (2 To reduce the computation time consumed during the optimization process, we have proposed a database based optimization approach. After off-line calculation, the simulation results can be applied to on-line charge; (3 The novel database-based DP method is proposed and the simulation results illustrate that this method can effectively find the suboptimal charging strategies under a certain balance between the charging loss and charging time.

  13. A study of bone marrow failure syndrome in children

    Directory of Open Access Journals (Sweden)

    Gupta V

    2008-01-01

    Full Text Available Background: Bone marrow failure syndrome (BMFS, or aplastic anemia, includes peripheral blood single cytopenias, as well as pancytopenia due to inability of the marrow to effectively produce blood cells. Aim: To study the clinico-hematological profile and etiological factors of bone marrow failure syndrome in children. Setting and Design: This prospective study was carried out in the Department of Pediatrics of a university teaching hospital over 36 months. Materials and Methods: Children with pancytopenia (Hb < 10 g/dl, absolute neutrophil count < 1.5 x 10 9 /L, platelet count < 100 x 10 9 /L and bone marrow cellularity < 25% were included in the study. History of exposure to drugs, socioeconomic status, ethnicity and occupation of father were noted. Bone marrow aspiration; trephine biopsy; Ham test; viral studies for hepatitis A, B and C; and cytogenetic investigations were carried out. Statistical Analysis: Relative risk was estimated by odds ratio (OR with 95% confidence interval (CI in matched cases and controls. Results: Of the 53 children studied, 6 (11.3% were diagnosed as Fanconi anemia. Two cases had features of myelodysplastic syndrome. Forty-five children were labeled as acquired aplastic anemia, of whom one had evidence of hepatitis B infection and two patients (5.8% had paroxysmal nocturnal hemoglobinuria. Aplastic anemia was more common in children from family with lower socioeconomic status; in Muslims; and where the father′s occupation was weaving, dyeing and painting. However, the number was small to make statistically significant conclusions. No correlation could be established with exposure to drugs. Conclusion: Fanconi anemia was responsible for approximately one-tenth of the cases of bone marrow failure syndrome. Majority of the patients had acquired aplastic anemia. Hepatitis B infection was an uncommon cause of acquired aplastic anemia.

  14. Workplace Charging. Charging Up University Campuses

    Energy Technology Data Exchange (ETDEWEB)

    Giles, Carrie [ICF International, Fairfax, VA (United States); Ryder, Carrie [ICF International, Fairfax, VA (United States); Lommele, Stephen [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-03-01

    This case study features the experiences of university partners in the U.S. Department of Energy's (DOE) Workplace Charging Challenge with the installation and management of plug-in electric vehicle (PEV) charging stations.

  15. [Treatment outcome for myelodysplastic syndromes (MDS) obtained by the Polish Children's Leukemia/Lymphoma Study Group].

    Science.gov (United States)

    Chybicka, A; Kołecki, P; Pietras, W; Bogusławska-Jaworska, J; Wójcik, D; Armata, J; Eliasińska, A; Kowalczyk, J; Jackowska, T; Klus, K; Matysiak, M; Krauze, A; Stefańska, K; Rokicka-Milewska, R; Wiśniewska-Slusarz, H

    1998-02-01

    Fourty children with MDS treated in seven centres of The Polish Children's Leukemia Lymphoma Study Group in period 1975-1998y were included to the study. In 16 children RAEB-T, in 2 CMML in 10 RA and in 12 RAEB were diagnosed. Our and literature data showed that BMT is the best therapy for children with MDS. For children, who don't have a donor for BMT. Roacutan therapy seems to be the most effective. PMID:9686518

  16. A Clinicopathological Study on Aortic Valves in Children

    Institute of Scientific and Technical Information of China (English)

    HUANG Ping; WANG Hongwei; ZHANG Zhenlu; HU Xiufen; LI Yanping; CHENG Peixuan; LIU Jianying

    2007-01-01

    In order to investigate the clinicopathological characteristics of aortic valve disease in children, all the native surgically excised aortic valves obtained between January 2003 and December 2005 were studied macroscopically and microscopically. The patients' medical records were reviewed and the clinical information was extracted. According to preoperative echocardiography, intraoperative assessment, and postoperative pathology, combined with clinical symptoms and signs, aortic valve diseases were divided into three categories: aortic stenosis (AS), aortic insufficiency (AI), and aortic stenosis with insufficiency (AS-AI). The etiology was determined according to the macroscopic, microscopic and clinical findings. The results showed that among 70 aortic valves, patient age ranged from 6 to 18 years, with a mean of 15.4 years, and there were 56 boys and 14 girts (male: female=4:1). Forty-four children only had pure aortic valve disease, and the other 26 children had aortic valve disease associated with other heart valve diseases. There were 5 cases of AS (7.14%), 60 cases of AI (85.71%) and 5 cases of AS-AI (7.14%). The causes were congenital aortic valve malformation (32 cases, 45.71%), rheumatic disease (28 cases, 40%), infective endocarditis (7 cases,10%), Marfan syndrome (2 cases, 2.86%), and undetermined (1 case, 1.43%). It was concluded that the common causes of aortic valve disease in order of frequency in children were congenital aortic valve malformation, rheumatic disease, infective endocarditis, and Marfan syndrome. AI was more common in children with aortic valve disease. Compared with adult patients, congenital bicuspid aortic valve in children was often AI. Histologically, the leaflets of congenital bicuspid aortic valve were mainly myxomatous, fibrosis and calcification less seen. AI was frequently found in rheumatic disease, mostly associated with other heart valve diseases. Macroscopic and microscopic examinations together with clinical

  17. Clinical study on unilateral hearing loss in children

    International Nuclear Information System (INIS)

    A series of 60 children was studied (aged 0 to 10 years, 32 boys, 28 girls) with severe unilateral sensorineural hearing loss of unknown etiology. There were two peaks, at 0 and 6 years. In 19 children, hearing loss was identified during a conservative general health checkup for school or preschool children. In 21 children aged 0 years, 16 were suspected of hearing loss by newborn hearing screening. Temporal bone computed tomography scans were examined in 51 patients. Sixteen ears (31.4%) with hearing loss had inner ear and/or internal auditory canal abnormalities. In one patient, the anomaly was the presence of a bony wall dividing the internal auditory canal into two separate compartments associated with severe inner ear hypoplasia. Two patients had a common cavity. In one of these patients, the anomaly was revealed because of severe bacterial meningitis, and another was detected by newborn hearing screening. Six patients had a narrow internal auditory canal, 4 had a narrow internal auditory canal and hypoplastic cochlea, and 1 had a narrow internal auditory canal and cystic vestibule, and lateral semicircular canal dysplasia. Two patients had a cystic vestibule and lateral semicircular canal dysplasia. One case showed fluctuation of the hearing level in the contralateral ear with normal hearing during the observation period at an average of 20 months. The number of children whose unilateral hearing loss is detected early by newborn hearing screening has enormously increased. Strategies for follow-up, early intervention, and support for families are necessary for young children with unilateral hearing impairment. (author)

  18. A longitudinal study on gross motor development in children with learning disorders

    NARCIS (Netherlands)

    Westendorp, Marieke; Hartman, Esther; Houwen, Suzanne; Huijgen, Barbara C. H.; Smith, Joanne; Visscher, Chris

    2014-01-01

    This longitudinal study examined the development of gross motor skills, and sex-differences therein, in 7; to 11-years-old children with learning disorders (LD) and compared the results with typically developing children to determine the performance level of children with LD. In children with LD (n

  19. Improvement of Fine Motor Skills in Children with Visual Impairment: An Explorative Study

    Science.gov (United States)

    Reimer, A. M.; Cox, R. F. A.; Nijhuis-Van der Sanden, M. W. G.; Boonstra, F. N.

    2011-01-01

    In this study we analysed the potential spin-off of magnifier training on the fine-motor skills of visually impaired children. The fine-motor skills of 4- and 5-year-old visually impaired children were assessed using the manual skills test for children (6-12 years) with a visual impairment (ManuVis) and movement assessment for children (Movement…

  20. Phonology and Syntax in French Children with SLI: A Longitudinal Study

    Science.gov (United States)

    Parisse, Christophe; Maillart, Christelle

    2007-01-01

    Maillart and Parisse found out that French children with specific language impairment (SLI) presented strong difficulties in phonology when compared with normally-developing children matched by MLU (NLD). Some of the youngest children from this study were followed to provide developmental information about their language deficit. Children were…

  1. Do Children Who Bully Their Peers Also Play Violent Video Games? A Canadian National Study

    Science.gov (United States)

    Dittrick, Crystal J.; Beran, Tanya N.; Mishna, Faye; Hetherington, Ross; Shariff, Shaheen

    2013-01-01

    The study examined whether children who bully others are likely to prefer playing video games that are rated high in maturity and violence. A stratified random sample of Canadian children ages 10 to 17 years from the provinces of Canada was obtained. Parents (n = 397) and their children (n = 492) completed an online survey of children's…

  2. Phonological Development in Specific Contexts: Studies of Chinese-Speaking Children. Child Language and Development.

    Science.gov (United States)

    Hua, Zhu

    This book examines the phonological development and impairment of Chinese-speaking children. It contains a series of studies of phonological acquisition and development of children in specific contexts (Putonghua or Modern Standard Chinese, the language variety promoted by the Chinese government, and normally developing children, children with…

  3. Children and bicycles: what is really happening? Studies of fatal and non-fatal bicycle injury.

    OpenAIRE

    Acton, C. H.; Thomas, S; Nixon, J. W.; Clark, R; Pitt, W R; Battistutta, D.

    1995-01-01

    OBJECTIVES: The objectives of the study were to ascertain the causes of accidents, injuries, and deaths in children who ride bicycles. Fatality and injury rates were also studied in order to compare with other studies. METHODS: Two studies of children were undertaken in children aged less than 15 years. In the first (retrospective fatality study), children who died as a result of a bicycle incident during the period 1981-92 were reviewed. In the second (prospective injury study) data were obt...

  4. Helminthic infestation in children of Kupwara district: A prospective study

    Directory of Open Access Journals (Sweden)

    Wani S

    2007-01-01

    Full Text Available The present study deals with the investigation of the frequency of intestinal helminth parasites in children of Kupwara, Kashmir, India. Three hundred and twelve children in the age group of 4-15 years were examined for different intestinal helminths in three schools located in rural areas. Two hundred and twenty two of 312 (71.15% tested positive for various intestinal helminths. The various helminth parasites included Ascaris lumbricoides , Trichuris trichiura , Enterobius vermicularis and Taenia saginata . By far, the highest frequency of 69.23% (216/312 was noted for Ascaris lumbricoides followed by Trichuris trichiura 30.76% (96/312, Enterobius vermicularis 7.69% (24/312 and Taenia saginata 7.69% (24/312. Single infection was found in 33.65% (105/312 and mixed infection was seen in 37.5% (117/312 children. This study emphasizes the need for improved environmental conditions, i.e., clean water supplies, enhanced sanitation and chemotherapy of school-age children in rural areas.

  5. HECTOR: a code for the study of high energy charged particles in axisymmetric tokamak plasmas

    International Nuclear Information System (INIS)

    A code for the study of high energy charged particles resulting primarily from thermonuclear reactions within the confining magnetic fields of non-circular axisymmetric tokamak plasmas is described. The trajectories of the particles are traced in the (C.O.M.) space using a new, fast, and efficient hybrid orbit following scheme based upon the drift equations in the guiding centre approximation and the constants of motion. The code includes the important Coulomb scattering processes of dynamical friction and pitch angle scattering. The code is specifically designed to operate within the experimental environment or in a predictive mode. (author)

  6. Study of charged kaon production in three-prong tau decays

    International Nuclear Information System (INIS)

    This thesis presents the measurement of kaon production in 3-prong τ decays. The data sample of Z0 events is used that was recorded with the DELPHI detector at LEP in 1992, 1993 and 1994. Charged kaons in the τ decay are identified on a track-by-track basis using the Ring Imaging Cherenkov detector (RICH). The branching ratios of τ-→K-K+π- (neutrals) ντ and τ-→K-π+π- (neutrals) ντ are determined. The resonance structure of these two decays is studied. Evidence for a simple QCD process of kaon pair production in τ decay is discussed. (orig.)

  7. Radiative and collisional processes of highly charged heavy ions studied with electron beam ion traps

    International Nuclear Information System (INIS)

    We have been studying radiative and collisional processes of highly charged heavy ions using two electron beam ion traps (EBITs) at the University of Electro-Communications (UEC/Tokyo); one is the Tokyo-EBIT constructed in 1995 for the operation with a high energy (up to 200 keV) electron beam, and another is “CoBIT” constructed recently for the operation with a low energy (< 1 keV) electron beam. Recent activities using the two EBITs are presented. (author)

  8. Comprehensive study of the effects of irradiation on charge collection efficiency in silicon detectors

    CERN Document Server

    Borello, L; Dutta, S; Gennai, Simone; Mariani, M; Messineo, A; Segneri, G; Starodumov, Andrei; Teodorescu, L; Tonelli, G; Verdini, P G

    2001-01-01

    The charge collection efficiency (CCE) for heavily irradiated silicon devices has been carefully investigated on a series of microstrip detectors. Large-area sensors designed for the CMS silicon tracker have been irradiated with neutrons and protons up to a very high fluence. Effects on CCE have been studied using a beam of minimum ionizing particles and a fast shaping time electronics similar to what is expected in CMS. The paper shows the performance of the sensors for CCE and signal-to-noise ratio under different operating conditions. (10 refs).

  9. Analytic study of the null singularity inside spherical charged black holes

    CERN Document Server

    Burko, L M; Burko, Lior M.; Ori, Amos

    1998-01-01

    We study analytically the features of the Cauchy horizon (CH) singularity inside a spherically-symmetric charged black hole, nonlinearly perturbed by a self-gravitating massless scalar field. We derive exact expressions for the divergence rate of the blue-shift factors, namely the derivatives in the outgoing direction of the scalar field $\\Phi$ and the area coordinate $r$. Both derivatives are found to grow along the contracting CH exactly like $1/r$. Our results are valid everywhere along the CH singularity, up to the point of full focusing. These exact analytic expressions are verified numerically.

  10. Exploring effective interactions through transition charge density study of 70,72,74,76Ge nuclei

    Indian Academy of Sciences (India)

    A Shukla; P K Raina; P K Rath

    2005-02-01

    Transition charge densities (TCD) for $0^{+} → 2_{1}^{+}$ excitation have been calculated for 70, 72, 74, 76Ge nuclei within microscopic variational framework employing 23/2, 15/2, 21/2 and 19/2 valence space. The calculated TCDs for different monopole variants of Kuo interaction are compared with available experimental results. Other systematics like reduced transition probabilities (2) and static quadrupole moments (2) are also presented. It is observed that the transition density study acts as a sensitive probe for discriminating the response of different parts of effective interactions.

  11. A Study on the Vibration of the Charging Belt in an Electrostatic Accelerator

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The vibration of the charging belt in an electrostatic accelerator has intense influences on the accelerator operation. A calculating model was set up in this paper to study the belt vibration. The results show that the belt tension, belt velocity and belt current all contribute to the belt vibration. There is an optimal relationship among the three factors by which the belt would run most smoothly. There exists a minimum value of optimal tension for various belt velocities. The vibrating frequency of the is generally around several Hz.

  12. Experimental study of charge collection in PN diodes irradiated by heavy ions

    International Nuclear Information System (INIS)

    Charge collection in PN Silicon diodes struck by heavy energetic ions, has been experimentally studied. Along the track, most of the free carriers in a diode under reverse bias are collected by drift and diffusion. A larger fast collection by drift than could be accounted for by drift in the depletion layer alone, is expected (FUNNEL). We have analysed a large set of data obtained at GANIL and Bruyeres-le-Chatel accelerators, in terms of collection depth. A general law has been deduced to describe the transient electronic phenomena as function of reverse bias of the junction and ion penetration

  13. Dynamics of Sewage Charge Policies, Environmental Protection Industry and Polluting Enterprises—A Case Study in China

    Directory of Open Access Journals (Sweden)

    Qingsong Wang

    2014-07-01

    Full Text Available The game model of sewage charges, based on incremental mode, was developed. Four modes of high/low sewage charge standards were utilized to analyze the relationship between control strategy on sewage discharge and the development of environmental protection industry. Results showed that the selection of control strategy was heavily dependent on the level of sewage charges. An empirical study was carried out to investigate the environmental protection industry in 31 regions in China in 2010. It was revealed that the sewage charge standards, formulated by the local governments and the development of environmental protection industry, varied significantly in different regions. The optimal level of environmental quality and social welfare, as a whole, was not achieved in China. It is proposed that different regions should adopt different sewage charges standards based on their economic development level and the current environmental quality. Similarly, the scientific and technological innovation of environmental protection industry should be further strengthened.

  14. Space charge effects in polymer-based light-emitting diodes studied by means of a polarization sensitive electroreflectance technique

    Science.gov (United States)

    Michelotti, F.; Bussi, S.; Dominici, L.; Bertolotti, M.; Bao, Z.

    2002-05-01

    We used a single wavelength electro-optical reflection technique to study the creation of space charge distributions in a polymer light emitting diode, by monitoring the real third order nonlinear optical response of the electroluminescent layer. The diode is based on an aluminum/polymer/indium tin oxide stack, where the polymer is a derivative of poly(p-phenylene-vinylene) in which oxidiazole groups were grafted as side chains. The measured signal is strongly influenced by a space charge distribution and by screening in the organic layer. The space charge distribution is the superposition of a long lived contribution, close to indium tin oxide, due to charges trapped in deep levels, and of that of relatively mobile charges injected in the polymer film. In the frame of a model which takes into account Debye-Hückel screening, with screening length equal to 100 nm we estimated the carrier density of the long lived charge distribution to be 4.8×1023 m-3, for a uniform distribution in a 110-nm-thick layer. The influence of the injection of mobile charges on the electro-optic signal is an order of magnitude smaller than that of trapped charges. The real third order susceptibility of the polymer is estimated to be χ(3)=4×10-21 m2/V2.

  15. Language networks in children: Evidence from functional MRI studies

    OpenAIRE

    Vannest, Jennifer; Karunanayaka, Prasanna R.; Schmithorst, Vincent J.; Szaflarski, Jerzy P; Holland, Scott K.

    2009-01-01

    We review functional MRI and other neuroimaging studies of language skills in children from infancy to adulthood. These studies show developmental changes in the networks of brain regions supporting language, which can be affected by brain injuries or neurological disorders. Particular aspects of language rely on networks that lateralize to the dominant hemisphere; others rely on bilateral or non-dominant mechanisms. Multiple fMRI tasks for pediatric patients characterize functional brain reo...

  16. STUDY OF ANEMIA AMONG PROTEIN ENERGY MALNOURISHED CHILDREN IN MYSORE

    Directory of Open Access Journals (Sweden)

    Nayana

    2015-02-01

    Full Text Available INTRODUCTION AND OBJECTIVES : Anemia in Protein energy malnutrition (PEM is common and its pathogenesis is multifactorial. Since the clinico - pathological patterns are reflected by their underlying etiopathogenic factors, it is important to study the associated morbidity and mortalit y and to establish their causes for an effective management. The purpose of the present study is to determine the prevalence, patterns, clinico - pathological and morphological types of anemia in protein energy malnutrition children. The objectives of the st udy are: (1 To study the clinico - pathological and morphological patterns of anemia in PEM children of age group 6 month – 5 years. (2 To assess the resultant morbidity and mortality. (3 To determine the ideal parameter for iron deficiency anemia. METHOD S: This study was conducted on 75 clinically diagnosed Protein energy malnutrition patients of age group 6 months to 5 years. Detailed clinical history elicitation and thorough clinical examination was performed. Peripheral smears of these patients were ex amined. The complete hemogram including reticulocyte count was done. The special investigations like bone marrow study, Hb electrophoresis, iron studies and stool examination were done whenever required. RESULTS: In our study, anemia in PEM affected female population more than the males of age 36 - 47 months. Most of children had Grade III PEM and Microcytic hypochromic anemia was most prevalent. Most of the children had Iron deficiency anemia. This study also indicated that Serum iron assay and TIBC are the better indicators of iron deficiency anemia in patients with PEM and it is the investigation of choice when compared to serum ferritin as it gets falsely elevated in these patients with infections confirmed by elevated CRP level. INTERPRETATION AND CONCLUS ION: Malnutrition, Infection and Anemia show a synergistic relationship. So it necessitates prompt screening and early diagnosis through proper

  17. Trends in resource utilization by children with neurological impairment in the United States inpatient health care system: a repeat cross-sectional study.

    Directory of Open Access Journals (Sweden)

    Jay G Berry

    2012-01-01

    Full Text Available BACKGROUND: Care advances in the United States (US have led to improved survival of children with neurological impairment (NI. Children with NI may account for an increasing proportion of hospital resources. However, this assumption has not been tested at a national level. METHODS AND FINDINGS: We conducted a study of 25,747,016 US hospitalizations of children recorded in the Kids' Inpatient Database (years 1997, 2000, 2003, and 2006. Children with NI were identified with International Classification of Diseases, 9th Revision, Clinical Modification diagnoses resulting in functional and/or intellectual impairment. We assessed trends in inpatient resource utilization for children with NI with a Mantel-Haenszel chi-square test using all 4 y of data combined. Across the 4 y combined, children with NI accounted for 5.2% (1,338,590 of all hospitalizations. Epilepsy (52.2% [n = 538,978] and cerebral palsy (15.9% [n = 164,665] were the most prevalent NI diagnoses. The proportion of hospitalizations attributable to children with NI did not change significantly (p = 0.32 over time. In 2006, children with NI accounted for 5.3% (n = 345,621 of all hospitalizations, 13.9% (n = 3.4 million of bed days, and 21.6% (US$17.7 billion of all hospital charges within all hospitals. Over time, the proportion of hospitalizations attributable to children with NI decreased within non-children's hospitals (3.0% [n = 146,324] in 1997 to 2.5% [n = 113,097] in 2006, p<.001 and increased within children's hospitals (11.7% [n = 179,324] in 1997 to 13.5% [n = 209,708] in 2006, p<0.001. In 2006, children with NI accounted for 24.7% (2.1 million of bed days and 29.0% (US$12.0 billion of hospital charges within children's hospitals. CONCLUSIONS: Children with NI account for a substantial proportion of inpatient resources utilized in the US. Their impact is growing within children's hospitals. We must ensure that the current health care system is staffed, educated, and equipped to

  18. Refractive Error, Visual Acuity and Causes of Vision Loss in Children in Shandong, China. The Shandong Children Eye Study

    OpenAIRE

    Jian Feng Wu; Hong Sheng Bi; Shu Mei Wang; Yuan Yuan Hu; Hui Wu; Wei Sun; Tai Liang Lu; Xing Rong Wang; Jonas, Jost B.

    2013-01-01

    PURPOSE: To examine the prevalence of refractive errors and prevalence and causes of vision loss among preschool and school children in East China. METHODS: Using a random cluster sampling in a cross-sectional school-based study design, children with an age of 4-18 years were selected from kindergartens, primary schools, and junior and senior high schools in the rural Guanxian County and the city of Weihai. All children underwent a complete ocular examination including measurement of uncorrec...

  19. Refractive Error, Visual Acuity and Causes of Vision Loss in Children in Shandong, China. The Shandong Children Eye Study

    OpenAIRE

    Wu, Jian Feng; Bi, Hong Sheng; Wang, Shu Mei; Hu, Yuan Yuan; Wu, Hui; Sun, Wei; Lu, Tai Liang; Wang, Xing Rong; Jonas, Jost B.

    2013-01-01

    Purpose To examine the prevalence of refractive errors and prevalence and causes of vision loss among preschool and school children in East China. Methods Using a random cluster sampling in a cross-sectional school-based study design, children with an age of 4–18 years were selected from kindergartens, primary schools, and junior and senior high schools in the rural Guanxian County and the city of Weihai. All children underwent a complete ocular examination including measurement of uncorrecte...

  20. Resilience among children exposed to traumatic loss : a study of children orphaned by AIDS in Addis Ababa, Ethiopia.

    OpenAIRE

    2008-01-01

    Objective: While traumatic parental loss presents an undeniable risk factor for maladaptive outcomes, some groups of children appear to manifest successful adaptation and do not follow a negative developmental pathway. The purpose of the present study was to test to what degree children orphaned by AIDS demonstrate resilience. Method: The self-report version of the strengths and difficulties questionnaire for children age ranging from 11-16 (SDQ S11-16), and a background information inventor...

  1. Study and Implementation on Batteries Charging Method of Micro-Grid Photovoltaic Systems

    OpenAIRE

    Tiezhou Wu; Qing Xiao; Linzhang Wu; Jie Zhang; Mingyue Wang

    2011-01-01

    In the micro-grid photovoltaic systems, the random changes of solar radiation enable lead-acid batteries to experience low SOC (State of Charge) or overcharged for periods of time if directly charged with such traditional methods as decreased charging current, which will reduce lifetime of batteries. What’s more, it’s difficult to find a proper reduction coefficient in decreasing charging current. To adapt to the random changes of circumstance and avoid selecting the reduction coefficient, a ...

  2. Experimental study of the fragmentation of water clusters induced by multiply charged ions

    OpenAIRE

    Maisonny, Rémi

    2011-01-01

    This work deals with the fragmentation of neutral water clusters induced by collisions with slow and swift multiply charged ions. Strong projectile charge dependence is found for all of the fragmentation patterns in the charge transfer regime. When increasing the projectile charge (from q = 2 to q = 20), we observe a modification of the scenario of the fragmentation dynamics with a transition from a partial dissociation to a full cluster explosion. We observe that water clusters are more stro...

  3. Young children's experiences of participating in group treatment for children exposed to intimate partner violence: A qualitative study.

    Science.gov (United States)

    Pernebo, Karin; Almqvist, Kjerstin

    2016-01-01

    The risk of exposure to intimate partner violence (IPV) between caregivers is increased during early childhood. The adverse effects on the health and development of the youngest children may be severe. Effective and promising interventions for children who have experienced IPV have been developed and evaluated. However, there is a lack in knowledge about how the children themselves experience the interventions. The aim of this study was to contribute to the evaluation of group treatment designed to improve the psychological health of young children in the aftermath of family violence by elucidating the children's experiences of participating. Nine children, aged 4 to 6 years, were interviewed after participating in group programmes specifically designed for children who have been exposed to intimate partner violence. A semi-structured interview guide with open-ended questions was used. The interviews were transcribed and analysed using interpretative phenomenological analysis, to ensure a focus on the children's own views and experiences. Five master themes embracing the children's experiences were identified: joy - positive emotional experience of participation; security - feeling safe; relatedness - relationships within the group; to talk - externalised focus on the violence; and competence - new knowledge and skills. Theoretical and clinical implications and the benefit of including very young children's views and experiences in research are discussed. PMID:25410886

  4. Oral habits in children--a prevalence study.

    Science.gov (United States)

    Shetty, S R; Munshi, A K

    1998-06-01

    This epidemiological study was conducted upon 4,590 school children to find the prevalence of oral habits in Mangalore in relation to their age and sex and to find the correlation, if any, between the habits and the malocclusion status. We noted that 29.7% of the population had habits of which 3. 1% had digit sucking, 4.6% mouth breathing, 3.02% tongue thrusting, 6.2% bruxism, 6% lip/cheek biting, 12.7% nail biting, 9.8% pencil biting and 0. 09% masochistic habits respectively. Digit sucking, pencil biting and tongue thrust were highly prevalent among Group 1 (3-6 years) children. Mouth breathing and bruxism were significant in Group 2 (7-12 years) cases whereas lip/cheek biting and nail biting were more common in Group 3 (13-16 years) cases. Digit sucking, tongue thrust, mouth breathing and bruxism were more prevalent among the boys whereas lip/cheek biting, nail biting and pencil biting were more prevalent among the girls. 28.95% of the children in Group 2 and 3 with habits had malocclusion. There was a significant correlation between class I type 2, class II div 1 and tongue thrust and mouth breathing whereas children with digit sucking showed a high correlation with class I type 2 malocclusion. PMID:11813757

  5. Laughter, Humor and Pain Perception in Children: A Pilot Study

    Directory of Open Access Journals (Sweden)

    Margaret Stuber

    2009-01-01

    Full Text Available Although there are many clinical programs designed to bring humor into pediatric hospitals, there has been very little research with children or adolescents concerning the specific utility of humor for children undergoing stressful or painful procedures. Rx Laughter™, a non-profit organization interested in the use of humor for healing, collaborated with UCLA to collect preliminary data on a sample of 18 children aged 7–16 years. Participants watched humorous video-tapes before, during and after a standardized pain task that involved placing a hand in cold water. Pain appraisal (ratings of pain severity and pain tolerance (submersion time were recorded and examined in relation to humor indicators (number of laughs/smiles during each video and child ratings of how funny the video was. Whereas humor indicators were not significantly associated with pain appraisal or tolerance, the group demonstrated significantly greater pain tolerance while viewing funny videos than when viewing the videos immediately before or after the cold-water task. The results suggest that humorous distraction is useful to help children and adolescents tolerate painful procedures. Further study is indicated to explore the specific mechanism of this benefit.

  6. STUDY OF LACTOSE INTOLERANCE IN CHILDREN BELOW 24 M ONTHS

    Directory of Open Access Journals (Sweden)

    Shabd Singh

    2013-05-01

    Full Text Available ABSTRACT: OBJECTIVE: To study the incidence of transient lactose intole rance in children below 24 months and to determine the need of discon tinuation of breast feeding and necessity of lactose free formula. MATERIAL AND METHODS: Randomly selected 100 children below 24 months of age, who were admitted in department of p ediatrics, S.S. Medical College and Associated G.M. Hospital Rewa, 70 of them were grou ped as cases with diarrhea, abdominal distention, vomiting, perianal excoriation and 30 w ere age and sex matched control. After collection of stool, pH, reducing substances in sto ol was determined and osazone test was performed to identify the types of reducing substan ces. RESULT: Out of 70 cases with diarrhoea, 22 (31.4% were found to have evidence o f lactose intolerance. Besides loose motion, in lactose intolerance positive cases, most common presenting symptoms were abdominal distention, perianal excoriation and vomiting. Inci dence of lactose intolerance was less in children who were on exclusive breast feeding till 6 months. In lactose intolerance positive as well as negative group duration of diarrhea after a dmission was same inspite of continuation of breast feeding. CONCLUSION: - Presence of abdominal distention, frothy character of stool, and perianal excoriation are suggestive of lactose into lerance. Lactose free formula and withdrawal of breast milk are not necessary in children with a cute diarrhea and persistent diarrhea having transient lactose intolerance.

  7. Proposed motor development assessment protocol for epidemiological studies in children.

    Science.gov (United States)

    Rosenbaum, P L; Missiuna, C; Echeverria, D; Knox, S S

    2009-01-01

    This paper proposes an approach to the implementation of a large-scale epidemiological study of child development. It addresses specifically how one might assess gross motor development longitudinally in a large population-based study of children, and recommends a three-phase process. Phase I, applied at key ages with the entire population, involves the use of parent-report screening tools that ask about specific age-appropriate motor skills, as well as any parental concerns about "quantity" or "quality" of their child's motor function and about any loss of motor function. In phase II, children who "fail" the screening phase (at any stage) are evaluated with specified developmental motor assessments. Those who "pass" revert to the screening stream, while those who "fail" continue to phase III. In this third component of the study, children are referred to experts in child development formally engaged in the study (including developmental paediatricians, paediatric neurologists and developmental therapists). These experts will use protocol-based evaluations to ascertain whether a child has a problem in development, what the problem might be from a diagnostic perspective, how "severe" the problem is, and what management services are or should be provided. It is argued that this is an efficient approach to the study of a population that would enable investigators to detect specific relatively common developmental motor disorders (in particular, cerebral palsy and developmental coordination disorder). PMID:19098137

  8. Effect of cycloplegia on the refractive status of children: the Shandong children eye study.

    Directory of Open Access Journals (Sweden)

    Yuan Yuan Hu

    Full Text Available To determine the effect of 1% cyclopentolate on the refractive status of children aged 4 to 18 years.Using a random cluster sampling in a cross-sectional school-based study design, children with an age of 4-18 years were selected from kindergardens, primary schools, junior and senior high schools in a rural county and a city. Auto-refractometry was performed before and after inducing cycloplegia which was achieved by 1% cyclopentolate eye drops.Out of 6364 eligible children, data of 5999 (94.3% children were included in the statistical analysis. Mean age was 10.0±3.3 years (range: 4-18 years. Mean difference between cycloplegic and non-cycloplegic refractive error (DIFF was 0.78±0.79D (median: 0.50D; range: -1.00D to +10.75D. In univariate analysis, DIFF decreased significantly with older age (P<0.001;correlation coefficient r:-0.24, more hyperopic non-cycloplegic refractive error (P<0.001;r = 0.13 and more hyperopic cycloplegic refractive error (P<0.001;r = 0.49. In multivariate analysis, higher DIFF was associated with higher cycloplegic refractive error (P<0.001; standardized regression coefficient beta:0.50; regression coefficient B: 0.19; 95% confidence interval (CI: 0.18, 0.20, followed by lower intraocular pressure (P<0.001; beta: -0.06; B: -0.02; 95%CI: -0.03, -0.01, rural region of habitation (P = 0.001; beta: -0.04; B: -0.07; 95%CI: -0.11, -0.03, and, to a minor degree, with age (P = 0.006; beta: 0.04; B: 0.009; 95%CI: 0.003, 0.016. 66.4% of all eyes with non-cycloplegic myopia (≤-0.50D remained myopic after cycloplegia while the remaining 33.6% of eyes became emmetropic (18.0% or hyperopic (15.7% under cycloplegia. Prevalence of emmetropia decreased from 37.5% before cycloplegia to 19.8% after cycloplegia while the remaining eyes became hyperopic under cycloplegia.The error committed by using non-cycloplegic versus cycloplegic refractometry in children with mid to dark-brown iris color decreased with older age, and in parallel

  9. Defect and charge transfer studies on hybrid solar cells with silicon nanocrystals

    Energy Technology Data Exchange (ETDEWEB)

    Niesar, Sabrina; Fabian, Wolfgang; Erhard, Nadine; Stegner, Andre; Brandt, Martin; Stutzmann, Martin [Walter Schottky Institut, Technische Universitaet Muenchen, 85748 Garching (Germany); Herrmann, Daniel; Riedle, Eberhard [Ludwig-Maximilians-Universitaet Muenchen, 80538 Muenchen (Germany); Pereira, Rui [University of Aveiro, 3810-193 Aveiro (Portugal); Wiggers, Hartmut [Institut fuer Verbrennung und Gasdynamik, Universitaet Duisburg-Essen, 47057 Duisburg (Germany)

    2011-07-01

    Hybrid inorganic nanoparticle-polymer solar cells are a promising alternative to purely organic devices due to the broad spectral range of absorption of the inorganic material. In this work, a combination of P3HT and silicon nanocrystals (Si-ncs), which are synthesized in a microwave plasma reactor, is studied. In particular, we focus on methods to decrease the concentration of silicon dangling bond defects which negatively affect the electronic properties of the hybrid solar cells. HF etching in combination with vacuum annealing at 200 C leads to the lowest defect densities. Conductivity measurements in vacuum show that the defect reduction results in improved electrical properties of Si-nc thin films. Electron paramagnetic resonance and Fourier transform infrared spectroscopy are used to study the stability of the different post-growth treatments. The charge transfer across the organic-inorganic interface is investigated via broadband-femtosecond optical pump-probe spectroscopy. We find that the addition of the Si-ncs leads to an increase of the charge separation as compared to pure P3HT.

  10. Recent Advances in Computational Studies of Charge Exchange X-ray Emission

    Science.gov (United States)

    Cumbee, Renata

    2016-06-01

    Interest in astrophysical sources of charge exchange (CX) has grown since X-ray emission from comet Hyakutake was first observed, the origin of which is primarily due to CX processes between neutral species in the comet’s atmosphere and highly charged ions from the solar wind. More recent observations have shown that CX may have a significant contribution to the X-ray emission spectra of a wide variety of environments within our solar system including solar wind charge exchange (SWCX) with neutral gases in the heliosphere and in planetary atmospheres, as well as beyond the solar system in galaxy clusters, supernova remnants, and star forming galaxies.While the basic process of CX has been studied for many decades, the reliability of the existing data is not uniform, and the coverage of the astrophysically important projectile and target combinations and collisional velocities is insufficient. The need for reliable and robust CX X-ray emission models will only be amplified with the with the high resolution X-ray spectra expected from the soft X-ray imaging calorimeter spectrometer (SXS) onboard the Hitomi X-ray observatory. In this talk, I will discuss recent advances in theoretical CX cross sections and X-ray modeling with a focus on CX diagnostics. The need for experimental X-ray spectra and cross sections for benchmarking current theory will also be highlighted. This work was performed in collaboration with David Lyons, Patrick Mullen, David Schultz, Phillip Stancil, and Robin Shelton. Work at UGA was partially supported by NASA grant NNX09AC46G.

  11. Comparison of oral health status between children with cerebral palsy and normal children in India: A case–control study

    OpenAIRE

    Sinha, Nidhi; Singh, Bijay; Chhabra, Kumar Gaurav; Patil, Santosh

    2015-01-01

    Background: The aim of the present research was to describe and compare the oral health of children with cerebral palsy (CP) with the normal children in India. Materials and Methods: Fifty children with CP of the age range 7-17 years and fifty normal children were selected for the study. An oral examination was carried out and decayed, missing, and filled teeth (dmft/DMFT) index, oral hygiene index-simplified (OHI-S) index, Angles malocclusion were charted along with other significant dental ...

  12. New Missions and the Future of Solar Wind Charge Exchange Studies

    Science.gov (United States)

    Kuntz, K. D.

    2016-04-01

    Several newly approved missions in astrophysics and heliophysics will study solar wind charge-exchange (SWCX) directly as either primary or secondary science goals. Of these, SMILE and CuPID will study the magnetosheath by means of the SWCX emission and will provide a direct measure of the magnetospheric emission from in both the 1/4 keV and 3/4 keV bands. HaloSAT observations will be designed to minimize the magnetospheric component for its observations of the Galactic Halo, but will make at least some dedicated observations of heliospheric SWCX. I will outline the simulation needs and observational strategies required to study SWCX for astrophysical purposes.

  13. Comparative study of behavioural problems among epileptic children treated with phenobarbital with epileptic children treated with phenytoin

    Directory of Open Access Journals (Sweden)

    Mohsen Javadzadeh

    2011-01-01

    Full Text Available Background: Phenobarbital is recommended by WHO as the first line drug for the treatment of partial and generalized tonic clonic epilepsies in developing countries, however several clinical trials have recorded higher frequencies of behavioural problems associated with Phenobarbital than with other drugs or no treatment. We compared the frequency of behavioural problems among epileptic children treated with phenobarbital with epileptic children treated with phenytoin. Materials and Method: We conducted a case-control study to comparing of epileptic children treatment with neurological with epileptic children treated with phenytoin. Between November 2006 to March 2007, 74 children referred from child neurologic clinic who treated with phenobarbital or phenytoin for more than 2 months in Zahedan, assessed consecutively by the Rutters behaviour scale for children aged 6 years and older and by the preschool behaviour questionnaire for those 2-5 years.Results: The mean scores on the behaviour scales did not differ significantly between the phenobarbital and phenytoin groups in children aged 6 years and older. Irretability, attention deficit, disobedience and lack of energy in phenobarbital group more than phenytoin group in 2-5 years old children. Conclusion: Several clinical trials have recorded higher frequencies (20-60% of behavioural problems associated with phenobarbital than with other drugs but in our study evidence supports the acceptability of phenobarbital for epileptic children in developing countries

  14. Experiments Study on Charge Technology of Lead-Acid Electric Vehicle Batteries

    Institute of Scientific and Technical Information of China (English)

    LI Wen; ZHANG Cheng-ning

    2008-01-01

    The basic theory of the fast charge and several charge methods are introduced. In order to heighten charge efficiency of valve-regulated lead-acid battery and shorten the charge time, five charge methods are investigated with experiments done on the Digatron BNT 400-050 test bench. Battery current, terminal voltage, capacity, energy and terminal pole temperature during battery experiment were recorded, and corresponding curves were depicted. Battery capacity-time ratio, energy efficiency and energy-temperature ratio are put forward to be the appraising criteria of lead-acid battery on electric vehicle (EV). According to the appraising criteria and the battery curves, multistage-current/negative-pulse charge method is recommended to charge lead-acid EV battery.

  15. Epidemiological studies of dental caries in groups of Swedish children

    OpenAIRE

    Stecksén-Blicks, Christina

    1986-01-01

    In a cross-sectional study the extent and distribution of dental caries was studied in 817 children, 4, 8 and 13 years old in three areas inSweden. The importance of dietary habits, sugar intake, social conditions, professional dental care, oral hygiene and the use of fluorides on caries prevalence was analyzed. In a subsample, con­sisting of 88 8-year-olds and 91 13-year-olds the net caries increment during aone-year period was studied.In this longitudinal study, the salivary levels of lacto...

  16. The study of capacitive deionization behavior of a carbon nanotube electrode from the perspective of charge efficiency.

    Science.gov (United States)

    Li, Haibo; Liang, Sen; Gao, Mangmang; Li, Guolong; Li, Jin; He, Lijun

    2015-01-01

    In this work, the capacitive deionization (CDI) performance of a single-walled carbon nanotube (CNT) electrode has been studied from the point view of charge efficiency theory. It is revealed here that the charge efficiency of a CNT electrode is strongly dependent upon the cell voltage and solution concentration. Either the high cell voltage or the low ionic strength results in a high charge efficiency, implying that CDI is expected to be a promising technique for an aqueous solution with low ionic strength. Additionally, it is found that the high decay constant and high electrical double-layer capacity are beneficial to enhance electrosorption performance. PMID:25607673

  17. Feasibility study: honey for treatment of cough in children.

    OpenAIRE

    Naveed Ahmed; Alastair Sutcliffe; Claire Tipper

    2013-01-01

    Respiratory tract infections are an important health problem because of high incidence and economic costs. The World Health Organization identifies honey as a potential demulcent treatment for cough. The aim of this study is to determine: i) patient public perceptions towards a proposed randomized controlled trial (RCT) comparing the effects of honey to placebo for treatment of cough in children; ii) potential participation rates for proposed trial; iii) whether age and gender of parent or ch...

  18. Children and divorce: a study of Divorce Court supervision orders

    OpenAIRE

    Goode, Stephen

    1988-01-01

    This research study was of the making and administration of Divorce Court Supervision Orders. Although established in England and Wales in 1958, there has been no detailed examination of supervision in domestic proceedings. In the 1979 period, when the population was obtained, 6,935 Divorce Court Supervision Orders were made. This figure has reduced to approximately 5,000 in 1985, with a total of 26,50C) ongoing orders. The population consisted of 121 children in 62 family units. Supervisi...

  19. Development of a biomarkers database for the National Children's Study

    International Nuclear Information System (INIS)

    The National Children's Study (NCS) is a federally-sponsored, longitudinal study of environmental influences on the health and development of children across the United States (www.nationalchildrensstudy.gov). Current plans are to study approximately 100,000 children and their families beginning before birth up to age 21 years. To explore potential biomarkers that could be important measurements in the NCS, we compiled the relevant scientific literature to identify both routine or standardized biological markers as well as new and emerging biological markers. Although the search criteria encouraged examination of factors that influence the breadth of child health and development, attention was primarily focused on exposure, susceptibility, and outcome biomarkers associated with four important child health outcomes: autism and neurobehavioral disorders, injury, cancer, and asthma. The Biomarkers Database was designed to allow users to: (1) search the biomarker records compiled by type of marker (susceptibility, exposure or effect), sampling media (e.g., blood, urine, etc.), and specific marker name; (2) search the citations file; and (3) read the abstract evaluations relative to our search criteria. A searchable, user-friendly database of over 2000 articles was created and is publicly available at: http://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid=85844. PubMed was the primary source of references with some additional searches of Toxline, NTIS, and other reference databases. Our initial focus was on review articles, beginning as early as 1996, supplemented with searches of the recent primary research literature from 2001 to 2003. We anticipate this database will have applicability for the NCS as well as other studies of children's environmental health

  20. Probo, an Intelligent Huggable Robot for HRI Studies with Children

    OpenAIRE

    Goris, Kristof; Saldien, Jelle; Vanderborght, Bram; Lefeber, Dirk

    2010-01-01

    This chapter surveys some of the research trends in social robotics and its applications to human-robot interaction (HRI). The past four years a unique robotic research platform, called Probo, is developed by the Robotics & Multibody Mechanics (R&MM) group to study physical and cognitive human-robot interaction (HRI) with a special focus on children. The robot Probo is designed to act as a social interface, providing a natural interaction while employing human-like social cues and communicati...

  1. Cytokines and other immunological biomarkers in children's environmental health studies

    OpenAIRE

    Duramad, Paurene; Tager, Ira B.; Nina T. Holland

    2007-01-01

    Environmental exposures (e.g. pesticides, air pollution, and environmental tobacco smoke) during prenatal and early postnatal development have been linked to a growing number of childhood diseases including allergic disorders and leukemia. Because the immune response plays a critical role in each of these diseases, it is important to study the effects of toxicants on the developing immune system. Children's unique susceptibility to environmental toxicants has become an important focus of the ...

  2. Children of the "Sug": A Study of the Daily Lives of Street Children in Khartoum, Sudan, with Intervention Recommendations

    Science.gov (United States)

    Kudrati, Mustafa; Plummer, Mary L.; Yousif, Nassrin Dafaalla El Hag

    2008-01-01

    Objectives: The study examines street children's daily lives in Khartoum, Sudan to recommend ways to improve their conditions and to successfully assist them off the streets. Methods: In 2000-2001, eight researchers conducted participant observation for 7 weeks; 20 groups of children engaged in role-plays and drawing activities; over 500 children…

  3. How Does Linguistic Competence Enhance Cognitive Functions in Children? A Study in Multilingual Children with Different Linguistic Competences

    Science.gov (United States)

    Videsott, Gerda; Della Rosa, Pasquale Anthony; Wiater, Werner; Franceschini, Rita; Abutalebi, Jubin

    2012-01-01

    The aim of the present study was to investigate the attentional mechanisms of multilingual children with differential degrees of language competence. For this purpose, 118 children (61 female/57 male; mean age 10.9 years (SD = 0.29); early acquisition multilinguals) from the Ladin valleys in South Tyrol, Italy, performed the Attentional Network…

  4. A safety and tolerability study of differently-charged nanoparticles for local pulmonary drug delivery

    International Nuclear Information System (INIS)

    Nanoparticle (NP) based drug delivery systems provide promising opportunities in the treatment of lung diseases. Here we examined the safety and tolerability of pulmonary delivered NPs consisting of PEG-PLA as a function of particle surface charge. The rationale for such a comparison should be attributed to the differential pulmonary toxicity of positively and negatively charged PEG-PLA NP. Thus, the local and systemic effects of pulmonary administered NPs were investigated following 5 days of daily endotracheal instillation to BALB/c mice that were euthanized on the eighth or nineteenth day of the experiment. We collected bronchoalveolar lavages and studied hematological as well as histochemistry parameters. Notably, the cationic stearylamine based PEG-PLA NPs elicited increased local and systemic toxic effects both on the eighth and nineteenth day. In contrast, anionic NPs of similar size were much better tolerated with local inflammatory effects observed only on the eighth experimental day after pulmonary instillation. No systemic toxicity effect was observed although a moderate change was noted in the platelet count that was not considered to be of clinical significance. No pathological observations were detected in the internal organs following instillation of anionic NPs. Overall these observations suggest that anionic PEG-PLA NPs are useful pulmonary drug carriers that should be considered as a promising therapeutic drug delivery system.

  5. Real-time charge carrier motion in P3HT studied with Kelvin Probe Microscopy

    Science.gov (United States)

    Castaneda, Chloe; Zaidi, Alyina; Moscatello, Jason; Aidala, Katherine

    We have developed a technique that uses scanning probe microscopy (SPM) to study the real-time injection and extraction of charge carriers in organic semiconductor devices. We investigate P3HT (full name) in an inverted field effect transistor geometry with gold electrodes. By positioning the SPM tip at an individual location and using Kelvin probe microscopy to record the potential over time, we can record how the charge carriers respond to changing the backgate voltage while the source and drain electrodes are grounded. We see relatively fast screening for negative backgate voltages because holes are quickly injected into the P3HT film. The screening is slower for positive gate voltages, because some of these holes are trapped and therefore less mobile. We compare P3HT transistors with different fabrication procedures that are expected to change the trap distribution: no silanization of the oxide and no annealing, silanization and no annealing, and both silanization and annealing. By incrementally stepping the gate voltage, we probe different trap depths. The recorded change in potential over time is best fit by a double exponential, suggesting two physical mechanisms involved in screening. This work is supported by NSF Grant DMR-0955348, and the Center for Heirarchical Manufacturing at the University of Massachusetts, Amherst (NSF CMMI-1025020).

  6. Studies on multiply emitted secondary electrons (MUSE) in charged-particle solid interactions

    International Nuclear Information System (INIS)

    When energetic ions bombard solids, a large number of electrons are simultaneously emitted. We have studied MUltiply emitted Secondary Electrons (MUSE) from a carbon foil bombarded by 0.4-1.2 MeV/u H+ and H2+, and 0.8 MeV He+. The target foil (≅ 13 μg/cm2) was tilted 450 with respect to the incident beam. It has been observed that (i) the average number of electrons anti n emitted per proton is proportional to the stopping power as is expected, and (ii) the ratio of anti n for H2+ to that for the same velocity H+, anti n(H2+)/anti n(2H+), increases from 0.93 to 1.04 as the projectile energy increases from 0.4 to 1.2 MeV/u. The latter observation is discussed comparing it with an oscillatory feature of the stopping power for H2+ theoretically predicted as a 'vicinage' effect. anti n of 0.8 MeV He+ bombarding a carbon foil has been measured for exit charge states of qe = 1 and 2 separately. A very weak dependence of anti n on qe has been observed in contrast to the z2 dependence on the atomic number of the projectiles (anti n for qe = 1 and 2 are 10.4 and 11.6, respectively). The charge changing mean free path of ions in solids is evaluated from this observation. (orig.)

  7. Photophysical study of a charge transfer oxazole dye in micelles: Role of surfactant headgroups

    Energy Technology Data Exchange (ETDEWEB)

    Maiti, Jyotirmay [Department of Chemistry, West Bengal State University, Barasat, Kolkata 700126 (India); Sarkar, Yeasmin; Parui, Partha Pratim [Department of Chemistry, Jadavpur University, Kolkata 700032 (India); Chakraborty, Sandipan [Department of Microbiology, University of Calcutta, Kolkata 700019 (India); Biswas, Suman [Department of Chemistry, West Bengal State University, Barasat, Kolkata 700126 (India); Das, Ranjan, E-mail: ranjan.das68@gmail.com [Department of Chemistry, West Bengal State University, Barasat, Kolkata 700126 (India)

    2015-07-15

    Photophysics of 5-(4′′-dimethylaminophenyl)-2-(4′-sulfophenyl)oxazole, sodium salt (DMO) which undergoes intramolecular charge transfer in the excited state was studied in micelles. In the cationic and the nonionic micelles, significantly higher fluorescence quantum yield is observed in comparison to the anionic micelles, due to much lower accessibility of DMO to the water molecules in the former micelles than the latter. Time-resolved fluorescence decays were characterized by a fast (τ{sub 1}) and a slow (τ{sub 2}) component of decay in all the micelles. The fast decay component (τ{sub 1}) increases significantly in going from the anionic micelles to the cationic micelles, because of the poorly hydrated headgroup region of the latter micelles compared to the former. Furthermore, much higher value of the slow component of decay (τ{sub 2}) is observed for the cationic and the neutral micelles than the anionic micelles. This is attributed to the increased penetration of water molecules into the micellar core of the anionic micelles compared to the cationic and the neutral micelles. - Highlights: • Photophysics of the fluorophore are remarkably different in the cationic and the anionic micelles. • Differential hydration of the surfactant headgroups gives rise to significantly different fluorescence quantum yield and lifetime in oppositely charged micelles. • Electrostatic interactions fine tune location of the fluorophore in the micelle–water interface of ionic micelles.

  8. Experimental and modeling study on charge storage/transfer mechanism of graphene-based supercapacitors

    Science.gov (United States)

    Ban, Shuai; Jing, Xie; Zhou, Hongjun; Zhang, Lei; Zhang, Jiujun

    2014-12-01

    A symmetrical graphene-based supercapacitor is constructed for studying the charge-transfer mechanism within the graphene-based electrodes using both experiment measurements and molecular simulation. The in-house synthesized graphene is characterized by XRD, SEM and BET measurements for morphology and surface area. It is observed that the electric capacity of graphene electrode can be reduced by both high internal resistance and limited mass transfer. Computer modeling is conducted at the molecular level to characterize the diffusion behavior of electrolyte ions to the interior of electrode with emphasis on the unique 2D confinement imposed by graphene layers. Although graphene powder poses a moderate internal surface of 400 m2 g-1, the capacitance performance of graphene electrode can be as good as that of commercial activated carbon which has an overwhelming surface area of 1700 m2 g-1. An explanation to this abnormal correlation is that graphene material has an intrinsic capability of adaptively reorganizing its microporous structure in response to intercalation of ions and immergence of electrolyte solvent. The accessible surface of graphene is believed to be dramatically enlarged for ion adsorption during the charging process of capacitor.

  9. Feasibility Study of a Solar-Powered Electric Vehicle Charging Station Model

    Directory of Open Access Journals (Sweden)

    Bin Ye

    2015-11-01

    Full Text Available In China, the power sector is currently the largest carbon emitter and the transportation sector is the fastest-growing carbon emitter. This paper proposes a model of solar-powered charging stations for electric vehicles to mitigate problems encountered in China’s renewable energy utilization processes and to cope with the increasing power demand by electric vehicles for the near future. This study applies the proposed model to Shenzhen City to verify its technical and economic feasibility. Modeling results showed that the total net present value of a photovoltaic power charging station that meets the daily electricity demand of 4500 kWh is $3,579,236 and that the cost of energy of the combined energy system is $0.098/kWh. In addition, the photovoltaic powered electric vehicle model has pollutant reduction potentials of 99.8%, 99.7% and 100% for carbon dioxide, sulfur dioxide, and nitrogen oxides, respectively, compared with a traditional gasoline-fueled car. Sensitivity analysis results indicated that interest rate has a relatively strong influence on COE (Cost of Energy. An increase in the interest rate from 0% to 6% increases COE from $0.027/kWh to $0.097/kWh. This analysis also suggests that carbon pricing promotes renewable energy only when the price of carbon is above $20/t.

  10. Child Maltreatment in the "Children of the Nineties": A Cohort Study of Risk Factors

    Science.gov (United States)

    Sidebotham, Peter; Heron, Jon

    2006-01-01

    Aim: To analyze the multiple factors affecting the risk of maltreatment in young children within a comprehensive theoretical framework. Methods: The research is based on a large UK cohort study, the Avon Longitudinal Study of Parents and Children. Out of 14,256 children participating in the study, 293 were investigated by social services for…

  11. Case study Early psychomotor development of children from triple pregnancy – case study

    Directory of Open Access Journals (Sweden)

    Łucja Bieleninik

    2014-08-01

    Full Text Available The aim of this study was to analyze the specificity and dynamics of psychomotor development in children from triplet pregnancy. The studied group was composed of siblings from triple pregnancy (T1, T2, T3, including two girls and one boy. This longitudinal study comprised three stages: stage I – children aged 25 months, stage II – children aged 29 months, and stage III – children aged 38 months. At each stage, the psychomotor development of children was examined with the Third Edition of Bayley Scales of Infant and Toddler Development (BSID-III and subjectively by their mother. Additionally, medical and nursing documentation was analyzed. Individual psychomotor development of children from triple pregnancy is different with regards to various spheres, and has different rates and dynamics throughout consecutive years. Psychomotor development of children from triple pregnancies is determined by gender and postnatal clinical parameters, i.e. birth weight, head circumference, postnatal morbidity, and prematurity-related conditions.

  12. SICKLE CHILDREN VS NORMAL CHILDREN: A TRANSCRANIAL AND EXTRACRANIAL DOPPLER STUDY

    Directory of Open Access Journals (Sweden)

    R P Singhal

    2015-03-01

    Full Text Available A prospective hospital based study was carried out to evaluate the role of transcranial Doppler in sickle cell anemia for period of 2 yrs (July 2009- August 2011. A total of 100 children, 50 normal individuals in control group and 50 diagnosed sickle cell disease patients in sickle group were evaluated in the age group .Children were from Newborn to15 years of age, of which 62% were males and 38% were females. Common Carotid Artery (CCA, External Carotid Artery (ECA, Internal Carotid Artery (ICA, Vertebral Artery, Middle Carotid Artery (MCA, Anterior Carotid Artery (ACA, Posterior Carotid Artery (PCA was evaluated by Transcranial and Extracranial Doppler on both sides in sickle cell patient. The mean velocities in all the vessels were higher in sickle group patient as compared to normal group patients. Evaluation of Extracranial carotid vessels has not been done in previous published studies. Our study can act as benchmark in extracranial Doppler studies of sickle cell patients. We have not followed the patients of sickle cell disease till stroke, but we can say with certainty that increased values of velocity >200 cm/sec is an absolute indication for blood transfusion to prevent stroke, which was observed in 10% of sickle cell patient in our study where velocities reduced by 20-25 cm/sec after blood transfusion.

  13. Molecular structure and charge transfer contributions to nonlinear optical property of 2-Methyl-4-nitroaniline: A DFT study

    Science.gov (United States)

    Jasmine, G. Femina; Amalanathan, M.; Roy, S. Dawn Dharma

    2016-05-01

    The Charge transfer contributions to the second-order nonlinear optical properties of 2-Methyl-4-nitroaniline have been performed by means of DFT computation. The vibrational contribution studies of 2-Methyl-4-nitroaniline have also been performed using FTIR, FT-Raman analysis. More support on the experimental findings were added from the quantum chemical studies performed with DFT (B3LYP) method using 6-311++G(d,p)basis sets. Natural bond orbital analysis confirms the presence of intramolecular charge transfer and the hydrogen bonding interaction. The HOMO and LUMO analysis reveals the possibility of charge transfer within the molecule. The first order hyperpolarizability (α0) and related properties (β,α0 and Δα) of 2-Methyl-4-nitroaniline were calculated. In addition, molecular electrostatic potential (MEP), charge analysis also were investigated using theoretical calculations.

  14. Beam dynamics study of RFQ for CADS with a 3D space-charge-effect

    International Nuclear Information System (INIS)

    The ADS (accelerator driven subcritical system) project was proposed by the Chinese Academy of Sciences. The initial proton beams delivered from an electron cyclotron resonance ion source can be effectively accelerated by 162.5 MHz 4.2 m long room temperature radio-frequency-quadrupoles (RFQ) operating in CW mode. To test the feasibility of this physical design, a new Fortran code for RFQ beam dynamics study, which is space charge dominated, was developed. This program is based on Particle-In-Cell (PIC) technique in the time domain. Using the RFQ structure designed for the CADS project, the beam dynamics behavior is performed. The well-known simulation code TRACK is used for benchmarks. The results given by these two codes show good agreements. Numerical techniques as well as the results of beam dynamics studies are presented in this paper. (authors)

  15. Charged vanadium-benzene multidecker clusters: DFT and quantum Monte Carlo study.

    Science.gov (United States)

    Tokár, K; Derian, R; Mitas, L; Štich, I

    2016-02-14

    Using explicitly correlated fixed-node quantum Monte Carlo and density functional theory (DFT) methods, we study electronic properties, ground-state multiplets, ionization potentials, electron affinities, and low-energy fragmentation channels of charged half-sandwich and multidecker vanadium-benzene systems with up to 3 vanadium atoms, including both anions and cations. It is shown that, particularly in anions, electronic correlations play a crucial role; these effects are not systematically captured with any commonly used DFT functionals such as gradient corrected, hybrids, and range-separated hybrids. On the other hand, tightly bound cations can be described qualitatively by DFT. A comparison of DFT and quantum Monte Carlo provides an in-depth understanding of the electronic structure and properties of these correlated systems. The calculations also serve as a benchmark study of 3d molecular anions that require a balanced many-body description of correlations at both short- and long-range distances. PMID:26874484

  16. Charged vanadium-benzene multidecker clusters: DFT and quantum Monte Carlo study

    Science.gov (United States)

    Tokár, K.; Derian, R.; Mitas, L.; Štich, I.

    2016-02-01

    Using explicitly correlated fixed-node quantum Monte Carlo and density functional theory (DFT) methods, we study electronic properties, ground-state multiplets, ionization potentials, electron affinities, and low-energy fragmentation channels of charged half-sandwich and multidecker vanadium-benzene systems with up to 3 vanadium atoms, including both anions and cations. It is shown that, particularly in anions, electronic correlations play a crucial role; these effects are not systematically captured with any commonly used DFT functionals such as gradient corrected, hybrids, and range-separated hybrids. On the other hand, tightly bound cations can be described qualitatively by DFT. A comparison of DFT and quantum Monte Carlo provides an in-depth understanding of the electronic structure and properties of these correlated systems. The calculations also serve as a benchmark study of 3d molecular anions that require a balanced many-body description of correlations at both short- and long-range distances.

  17. Charged vanadium-benzene multidecker clusters: DFT and quantum Monte Carlo study

    International Nuclear Information System (INIS)

    Using explicitly correlated fixed-node quantum Monte Carlo and density functional theory (DFT) methods, we study electronic properties, ground-state multiplets, ionization potentials, electron affinities, and low-energy fragmentation channels of charged half-sandwich and multidecker vanadium-benzene systems with up to 3 vanadium atoms, including both anions and cations. It is shown that, particularly in anions, electronic correlations play a crucial role; these effects are not systematically captured with any commonly used DFT functionals such as gradient corrected, hybrids, and range-separated hybrids. On the other hand, tightly bound cations can be described qualitatively by DFT. A comparison of DFT and quantum Monte Carlo provides an in-depth understanding of the electronic structure and properties of these correlated systems. The calculations also serve as a benchmark study of 3d molecular anions that require a balanced many-body description of correlations at both short- and long-range distances

  18. Spectroscopic studies of charge transfer complexes between colchicine and some π acceptors

    Science.gov (United States)

    Arslan, Mustafa; Duymus, Hulya

    2007-07-01

    Charge transfer complexes between colchicine as donor and π acceptors such as tetracyanoethylene (TCNE), 2,3-dichloro-5,6-dicyano- p-benzoquinone (DDQ), p-chloranil ( p-CHL) have been studied spectrophotometrically in dichloromethane at 21 °C. The stoichiometry of the complexes was found to be 1:1 ratio by the Job method between donor and acceptors with the maximum absorption band at a wavelength of 535, 585 and 515 nm. The equilibrium constant and thermodynamic parameters of the complexes were determined by Benesi-Hildebrand and van't Hoff equations. Colchicine in pure form and in dosage form was applied in this study. The formation constants for the complexes were shown to be dependent on the structure of the electron acceptors used.

  19. Charged vanadium-benzene multidecker clusters: DFT and quantum Monte Carlo study

    Energy Technology Data Exchange (ETDEWEB)

    Tokár, K.; Derian, R. [Institute of Physics, CCMS, Slovak Academy of Sciences, 84511 Bratislava (Slovakia); Mitas, L. [Department of Physics, North Carolina State University, Raleigh, North Carolina 27695-8202 (United States); Štich, I., E-mail: ivan.stich@savba.sk [Institute of Physics, CCMS, Slovak Academy of Sciences, 84511 Bratislava (Slovakia); Ruprecht A. Institute of Technology, Bratislava (Slovakia)

    2016-02-14

    Using explicitly correlated fixed-node quantum Monte Carlo and density functional theory (DFT) methods, we study electronic properties, ground-state multiplets, ionization potentials, electron affinities, and low-energy fragmentation channels of charged half-sandwich and multidecker vanadium-benzene systems with up to 3 vanadium atoms, including both anions and cations. It is shown that, particularly in anions, electronic correlations play a crucial role; these effects are not systematically captured with any commonly used DFT functionals such as gradient corrected, hybrids, and range-separated hybrids. On the other hand, tightly bound cations can be described qualitatively by DFT. A comparison of DFT and quantum Monte Carlo provides an in-depth understanding of the electronic structure and properties of these correlated systems. The calculations also serve as a benchmark study of 3d molecular anions that require a balanced many-body description of correlations at both short- and long-range distances.

  20. Beam dynamics study of RFQ for CADS with a 3D space-charge-effect

    Science.gov (United States)

    Li, Chao; Zhang, Zhi-Lei; Qi, Xin; Xu, Xian-Bo; He, Yuan; Yang, Lei

    2014-03-01

    The ADS (accelerator driven subcritical system) project was proposed by the Chinese Academy of Sciences. The initial proton beams delivered from an electron cyclotron resonance ion source can be effectively accelerated by 162.5 MHz 4.2 m long room temperature radio-frequency-quadrupoles (RFQ) operating in CW mode. To test the feasibility of this physical design, a new Fortran code for RFQ beam dynamics study, which is space charge dominated, was developed. This program is based on Particle-In-Cell (PIC) technique in the time domain. Using the RFQ structure designed for the CADS project, the beam dynamics behavior is performed. The well-known simulation code TRACK is used for benchmarks. The results given by these two codes show good agreements. Numerical techniques as well as the results of beam dynamics studies are presented in this paper.

  1. Numerical study of the effects of space charge on periodic focusing. (Etude numerique d'effets de charge d'espace en focalisation periodique)

    International Nuclear Information System (INIS)

    Filamentation effects entailing emittance growth due to space charge in the transport of intense beams have been studied by numerical simulation. Programs tested on calculable cases in continuous focusing systems show for high intensities, in the case of periodic focusing and according to the periodicity, either instability-type phenomena appearing at intensities below the thresholds so far known or progressive, though slow, and regular growths of emittance, which allow more intense beams to be transported over moderate distances. At low intensities, emittances remain constant. No detailed theoretical interpretation of these results is proposed

  2. STUDY OF SEVERE MALNUTRITION IN PRESCHOOL CHILDREN OF MELGHAT

    Directory of Open Access Journals (Sweden)

    Meena Shelgaonkar

    2015-01-01

    Full Text Available i                Introduction:Melghat - tribal block of villages (with 87.5% tribal population in Maharashtra, (India unfortunately is known for malnutrition among children, despite lots of efforts taken by Govt. and NGOs.ii              Rationale: The study was conducted to examine the causes of malnutrition and awareness about consequences of malnutrition as a part of Post-graduate thesis.iii            Objective:Tocompare the status and causes of malnutrition in children below age five in Intervention and Control Villages in Melghat over a period of 2 months.iv             Materials and Methods: A questionnaire based survey method was used by selecting ten villages out of 40 using lottery method where MAHAN, Melghat is already working. Selected ten villages were from Intervention and Control groups (five each. In Intervention villages health and nutritional education awareness programs were conducted while in control group government programs such as 21 day care for severely malnourished children were going on but no health and nutritional education programs. Children’s weight, heights were taken and also general information like mothers educational status was collected in both groups by visiting all families. The data was analyzed for status of malnutrition in preschool children from these families and awareness about nutrition in mothers.v               Results:Status of malnutrition in preschool children was lower in Intervention villages (66.0 % as compared to that of Control villages (73.0 %, while prevalence was higher among the children whose mothers were illiterate. Malnutrition was higher in girls (70.5 %, 77.1 % as compared to that of boys (61.4 %, 68.7 % in both groups.vi             Conclusion: The analysis of study data from tenvillages suggested thatproper health and nutritional education about feeding is lacking in mothers. To reduce this childhood

  3. Development of a thermite charge container with actuated release for use in molten fuel coolant interaction studies

    International Nuclear Information System (INIS)

    Studies of Molten Fuel Coolant Interaction in progress at Winfrith require a controlled and consistent means of introducing the molten fuel into the coolant. The development of a reliable charge container capable of achieving those aims is reported here. Improvements in the integrity of the charge container and the means of controlling its release are fully described with comments on the success of its introduction into the MFCI programme. (author)

  4. Thermoluminescence study of the trapped charge at an alumina surface electrode in different dielectric barrier discharge regimes

    OpenAIRE

    Ambrico, P F; Ambrico, M.; Colaianni, A; Schiavulli, L; Dilecce, G; S. De Benedictis

    2010-01-01

    Abstract 52.25.-b {Plasma properties} PACS 52.25.Mq {Dielectric properties} PACS 51.50.+v {Electrical properties} PACS 78.60.Kn {Thermoluminescence} PACS 72.20.Jv {Charge carriers: generation, recombination, lifetime, and trapping} Abstract. In the present study charge trapping effect in alumina dielectric surfaces has been deeply investigated by means of a dedicated dielectric barrier discharge apparatus under different discharge regime and gas mixtures. These work further validates our p...

  5. Surface charge studies - an important approach for investigation of color removal from textile wastewaters by chemical coagulation

    OpenAIRE

    GAYDARDZHIEV, Stoyan; Ay, P.

    2003-01-01

    Results concerning surface charge characterizations of coagulated dye with an aim to evaluate the predominant destabilization mechanism taking place during colour removal by chemical coagulation are presented. A model wastewater comprising of commercially used dye with a CI “Reactive Red 2” was studied. The effect of the combination coagulant/flocculant on colour removal by filtration and sedimentation was evaluated in terms of progression of sludge surface charge. On that basis, an implicati...

  6. Regional study of ventilation with inhaled xenon 133 in children

    International Nuclear Information System (INIS)

    A regional exploration of pulmonary ventilation in a population of 104 infants and children by a study of distribution and washout of xenon 133 inhaled with rebreathing is carried out. The results are expressed by photographs (gamma-camera) and time-activity curves. The indications for regional exploration were oriented by the existence on the straight X-ray film of a localised ventilation disorder (a hyperlucent area or an opacity). This study permitted physiopathological analysis and guided endobronchial examinations. The functional results obtained, complete and explain other methods of exploration of lung function by spirography, ventilatory mechanics, transthoracic electrical measurements and study of lung perfusion with technetium 99m

  7. A STUDY OF EFFECTIVENESS OF METHODS USED FOR MODIFICATION OF PROBLEM BEHAVIOUR OF MENTALLY CHALLENGED CHILDREN

    OpenAIRE

    Mukesh Ahlawat

    2015-01-01

    In the present study the researcher has attempted to study the effectiveness of methods used for modification of problem behaviour of mentally challenged children. The investigation was carried out on 15 mentally challenged children of Awwa Asha School, Ambala Cantt. The investigation was done by using Mehta et al 's methods for modifications of problem behaviour in mentally challenged children. The findings of the study show that these method are very useful for mentally challenged children.

  8. An observational study on cough in children: epidemiology, impact on quality of sleep and treatment outcome

    OpenAIRE

    De Blasio, Francesco; Dicpinigaitis, Peter V; Rubin, Bruce K; De Danieli, Gianluca; Lanata, Luigi; Zanasi, Alessando

    2012-01-01

    Background Cough is one of the most frequent symptoms in children and is the most common symptom for which children visit a health care provider. Methods This is an observational study on acute cough associated with upper respiratory tract infection (URTI) in children. The study evaluates the epidemiology and impact of cough on quality of sleep and children's activities, and the outcome of cough with antitussive treatments in pediatric routine clinical practice. Study assessments were perform...

  9. Toilet Training in Iranian Children: Cross- Sectional Study

    Directory of Open Access Journals (Sweden)

    Ehsan Valavi

    2013-04-01

    Full Text Available Background: There is still controversy about the method and the age of toilet training and they are varied in different cultures. The aim of study is to determine the beliefs of Iranian parents about the appropriate age, the true age, the methods used for toilet training, and the association with voiding problems.Methods: 349 questionnaires contained items about demographic data, the belief of parents, the method applied, and the true age of accomplish toilet training were filled-out for children aged 2 month-5 year. In addition, pediatric lower urinary tract scoring system questionnaire were distributed among 217 children with lower urinary tract symptoms aged 5-15 years between 2008 and 2010 in outpatient clinics. P 0.05.There was no correlation between wetting episodes at day or night and the age of toilet training.

  10. Donkey-assisted rehabilitation program for children: a pilot study

    Directory of Open Access Journals (Sweden)

    Paola De Rose

    2011-12-01

    Full Text Available Bonding with animals grants access to the sphere of affectivity and facilitates therapeutic engagement. The methodological approach of donkey-assisted programs is based on mediation, which is characterized by multidirectional relationships (patient-donkey-therapist. The donkey is an excellent facilitator in the motivation-building process, being able to stimulate the child's development by way of active and positive forces that foster psycho-affective and psycho-cognitive development processes. Results of this study, which focused on the child's approach to the donkey, indicate that while communicating with the animal, children rely more on physical expressions than on verbal language. Donkey-assisted rehabilitative sessions can help in identifying children's strong points, on which motivation could be built.

  11. Polarization and charge limit studies of strained GaAs photocathodes

    International Nuclear Information System (INIS)

    This thesis presents studies on the polarization and charge limit behavior of electron beams produced by strained GaAs photocathodes. These photocathodes are the source of high-intensity, high-polarization electron beams used for a variety of high-energy physics experiments at the Stanford Linear Accelerator Center. Recent developments on P-type, biaxially-strained GaAs photocathodes have produced longitudinal polarization in excess of 80% while yielding beam intensities of ∼ 2.5 A/cm2 at an operating voltage of 120 kV. The SLAC Gun Test Laboratory, which has a replica of the SLAC injector, was upgraded with a Mott polarimeter to study the polarization properties of photocathodes operating in a high-voltage DC gun. Both the maximum beam polarization and the maximum charge obtainable from these photocathodes have shown a strong dependence on the wavelength of illumination, on the doping concentration, and on the negative electron affinity levels. The experiments performed for this thesis included studying the effects of temperature, cesiation, quantum efficiency, and laser intensity on the polarization of high-intensity beams. It was found that, although low temperatures have been shown to reduce the spin relaxation rate in bulk semiconductors, they don't have a large impact on the polarization of thin photocathodes. It seems that the short active region in thin photocathodes does not allow spin relaxation mechanisms enough time to cause depolarization. Previous observations that lower QE areas on the photocathode yield higher polarization beams were confirmed. In addition, high-intensity, small-area laser pulses were shown to produce lower polarization beams. Based on these results, together with some findings in the existing literature, a new proposal for a high-intensity, high-polarization photocathode is given. It is hoped that the results of this thesis will promote further investigation on the properties of GaAs photocathodes

  12. Music Therapy with Autistic Children: A Multiple Case Study

    Science.gov (United States)

    Pelayo, Jose Maria G., III; Sanchez, Celeste S.

    2013-01-01

    The aim of the researchers was to determine if there are alternative methods in treating children with autism. Children diagnosed with autism are currently attending special schools with a different type of curriculum. Many methods have been used by psychologists and psychiatrists to treat children diagnosed with autism. Children with mental or…

  13. Traumatic dental injuries in Serbian children: Epidemiological study

    Directory of Open Access Journals (Sweden)

    Vuković Ana

    2013-01-01

    Full Text Available Introduction. Comprehensive epidemiological data regarding factors associated with traumatic dental injuries are scarce. Objective. The aim of the present study was to assess the frequency and analyze the factors associated with traumatic dental injuries in Serbian children. Methods. Research included children and adolescents with traumatic dental injury aged 0-19 year during the period from 2003 to 2010, in four University Dental Centres in Serbia: Belgrade, Nis, Novi Sad and Kragujevac. Patient history, demographic, clinical and radiographic data were obtained from dental trauma forms. Results. Total of 2,194 patients (748 girls, 1,446 boys (χ2=222.1; p<0.01 with 3,077 injured teeth in permanent and 953 in primary dentition were observed. Most of patients were aged 7 to 12 years (n=1,191. The most frequent injuries in primary and permanent dentition were dislocations (87.4% and teeth fractures (50.8%, respectively (χ2=706.1; p<0.01. The most frequent mechanism of injury was fall in children aged 0 to 12 years, while the collisions were most frequent in adolescents (53.9%. The most frequent injuries in adolescents were inflicted outdoor (66.8%, while the injuries in children aged 0 to 3 years occurred at home (68.2%, (χ2=360.8; p<0.01. The most frequent injuries in girls were accidental (48.3%, and in boys these were sport injuries (20.4% and violence (10.4% (χ2=79.9; p<0.01. The most frequent cause of injury in children aged 0 to 3 years was accidental (75.6%, while in adolescents it was sport (34.1% (χ2=1102.7; p<0.01. Conclusion. Dental injuries in preschool children most frequently resulted from fall at home. Schoolchildren most frequently injured teeth outdoor during play. Violence and sport injuries were most frequent cause of injury in adolescents. [Projekat Ministarstva nauke Republike Srbije, br. 172026

  14. Study of charge of the top quark in the ATLAS experiment

    CERN Document Server

    Federič, Pavol

    2015-01-01

    A measurement of the top quark electric charge was carried out in the ATLAS experiment at the Large Hadron Collider (LHC) using 2.05 fb − 1 of data at a centre-of-mass energy of 7 TeV. In units of the elementary electric charge, the measured top quark charge is 0.64 ± 0.02 (stat.) ± 0.08 (syst.). This result strongly favours SM and excludes models with an exotic quark with charge − 4 / 3 instead of the top quark by more than 8 σ

  15. Parasomnias and sleep disordered breathing in Caucasian and Hispanic children – the Tucson children's assessment of sleep apnea study

    OpenAIRE

    Fregosi Ralph F; Kaemingk Kris L; Goodwin James L; Rosen Gerald M; Morgan Wayne J; Smith Terry; Quan Stuart F

    2004-01-01

    Abstract Background Recent studies in children have demonstrated that frequent occurrence of parasomnias is related to increased sleep disruption, mental disorders, physical harm, sleep disordered breathing, and parental duress. Although there have been several cross-sectional and clinical studies of parasomnias in children, there have been no large, population-based studies using full polysomnography to examine the association between parasomnias and sleep disordered breathing. The Tucson Ch...

  16. Systematic studies on the effect of linear lattice optics for space-charge limited beams

    Science.gov (United States)

    Fitterer, M.; Carli, C.; Molodozhentsev, A.; Müller, A.-S.

    2015-12-01

    The HL-LHC (High Luminosity LHC) project aims to an increase of the luminosity of the LHC by a factor of 10. In order to realize this ambitious goal, the LHC itself has to undergo a major upgrade accompanied by an extensive upgrade of the complete injector complex referred to as LHC injector upgrade (LIU). In the framework of the LIU project, a new rapid cycling synchrotron (RCS) as an alternative to the energy upgrade of the existing PS Booster has been proposed. Motivated by the optics studies conducted for this RCS, the more general question of the influence of the linear optics on the machine performance has been raised. In this paper, we want to investigate this question by comparing different lattices with the final aim of identifying lattice characteristics advantageous under strong space-charge effects.

  17. Study of charged kaon production in three-prong tau decays

    Energy Technology Data Exchange (ETDEWEB)

    Hao Wei

    1996-02-01

    This thesis presents the measurement of kaon production in 3-prong {tau} decays. The data sample of Z{sup 0} events is used that was recorded with the DELPHI detector at LEP in 1992, 1993 and 1994. Charged kaons in the {tau} decay are identified on a track-by-track basis using the Ring Imaging Cherenkov detector (RICH). The branching ratios of {tau}{sup -}{yields}K{sup -}K{sup +}{pi}{sup -} (neutrals) {nu}{sub {tau}} and {tau}{sup -}{yields}K{sup -}{pi}{sup +}{pi}{sup -} (neutrals) {nu}{sub {tau}} are determined. The resonance structure of these two decays is studied. Evidence for a simple QCD process of kaon pair production in {tau} decay is discussed. (orig.).

  18. Systematic studies on the effect of linear lattice optics for space-charge limited beams

    CERN Document Server

    Fitterer, M; Molodozhentsev, A; Müller, A S

    2015-01-01

    The HL-LHC (High Luminosity LHC) project aims to an increase of the luminosity of the LHC by a factor of 10. In order to realize this ambitious goal, the LHC itself has to undergo a major upgrade accompanied by an extensive upgrade of the complete injector complex referred to as LHC injector upgrade (LIU). In the framework of the LIU project, a new rapid cycling synchrotron (RCS) as an alternative to the energy upgrade of the existing PS Booster has been proposed. Motivated by the optics studies conducted for this RCS, the more general question of the influence of the linear optics on the machine performance has been raised. In this paper, we want to investigate this question by comparing different lattices with the final aim of identifying lattice characteristics advantageous under strong space-charge effects.

  19. Study on space charge effect in an electrostatic ion analyzer applied to measure laser produced ions

    International Nuclear Information System (INIS)

    The abundance of different ions produced by laser ion sources is usually analyzed by an electrostatic ion analyzer (EIA). Ion current intensities in the range of several mA/cm2 at the position of the EIA have been achieved from the laser ion source developed by the Institute of Modern Physics; this indicates that a noticeable influence of space charge effect during the ion transmission will occur. Hence, while the parameters of the EIA or the beams are changed, such as ion species, current intensity, the ions’ transmission efficiency through the EIA is different, which will result in an uncertainty in the estimation of the ions’ yields. Special attention is focused on this issue in this paper. Ion's transmissions through the EIA under different circumstances are studied with simulations and experiments, the results of which are consistent with each other

  20. A detection system for charged-particle decay studies with a continuous-implantation method

    Science.gov (United States)

    Sun, L. J.; Xu, X. X.; Lin, C. J.; Wang, J. S.; Fang, D. Q.; Li, Z. H.; Wang, Y. T.; Li, J.; Yang, L.; Ma, N. R.; Wang, K.; Zang, H. L.; Wang, H. W.; Li, C.; Shi, C. Z.; Nie, M. W.; Li, X. F.; Li, H.; Ma, J. B.; Ma, P.; Jin, S. L.; Huang, M. R.; Bai, Z.; Wang, J. G.; Yang, F.; Jia, H. M.; Zhang, H. Q.; Liu, Z. H.; Bao, P. F.; Wang, D. X.; Yang, Y. Y.; Zhou, Y. J.; Ma, W. H.; Chen, J.

    2015-12-01

    A new detection system with high detection efficiency and low detection threshold has been developed for charged-particle decay studies, including β-delayed proton, α decay or direct proton emission from proton-rich nuclei. The performance was evaluated by using the β-delayed proton emitter 24Si produced by projectile fragmentation at the First Radioactive Ion Beam Line in Lanzhou. Under a continuous-beam mode, the isotopes of interest were implanted into two double-sided silicon strip detectors, where the subsequent decays were measured and correlated to the preceding implantations by using position and time information. The system allows us to measure protons with energies down to about 200 keV without obvious β background in the proton spectrum. Further application of the detection system can be extended to the measurements of β-delayed proton decay and the direct proton emission of more exotic proton-rich nuclei.

  1. Space Charge Studies with High Intensity Single Bunch Beams in the CERN SPS

    CERN Document Server

    Bartosik, Hannes; Schmidt, Frank; Titze, Malte

    2016-01-01

    In order to reach the target beam parameters of the LHC injectors upgrade (LIU) project the beam degradation due to losses and emittance growth on the long injection plateau of the SPS needs to be minimized. A detailed study of the dependence of losses, transverse emittance blow-up and transverse beam tail creation as function of the working point is presented here for a high brightness single bunch beam with a vertical space charge tune spread of about 0.2 on the 26 GeV injection plateau. The beam behaviour close to important betatron resonances is characterised and a region in the tune diagram with minimal beam degradation is identified. Implications about the performance for LIU beams are discussed.

  2. Study of latent and etched tracks by a charged particle transmission technique

    CERN Document Server

    Vacik, J; Hnatowicz, V; Fink, D; Kobayashi, Y; Hirata, K; Apel, P Y; Strauss, P

    1999-01-01

    A recently suggested technique for non-destructive investigation of inhomogeneities in thin objects, which is based on the measurement of the energy spectra of charged particles transmitted through the object, is used for the study of thermal annealing of 10-20 mu m thick polyethylene terephtalate, polypropylene and polycarbonate foils irradiated with 1-10 MeV/amu heavy ions. At elevated temperature a foil linear contraction is observed on pristine and irradiated material. Also the foil roughness increases with increasing temperature. On the same foils with etched pores 0.5-1.0 mu m in diameter, the thermal annealing results in gradual closing of the pores up to about 30% of their initial diameter at the temperatures of 150-175 deg. C. At higher temperatures the pore diameter increases and achieves its initial value.

  3. Atomic physics studies of highly charged ions on tokamaks using x-ray spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Beiersdorfer, P.; von Goeler, S.; Bitter, M.; Hill, K.W.

    1989-07-01

    An overview is given of atomic physics issues which have been studied on tokamaks with the help resolution x-ray spectroscopy. The issues include the testing of model calculations predicting the excitation of line radiation, the determination of rate coefficients, and accurate atomic structure measurements. Recent research has focussed primarily on highly charged heliumlike (22 less than or equal to Z less than or equal to 28) and neonlike (34 less than or equal to Z less than or equal to 63) ions, and results are presented from measurements on the PLT and TFTR tokamaks. Many of the measurements have been aided by improved instrumental design and new measuring techniques. Remarkable agreement has been found between measurements and theory in most cases. However, in this review those areas are stressed where agreement is worst and where further investigations are needed. 19 refs., 13 figs., 2 tabs.

  4. Charge radii of magnesium isotopes by laser spectroscopy a structural study over the $sd$ shell

    CERN Multimedia

    Schug, M; Krieger, A R

    We propose to study the evolution of nuclear sizes and shapes over the magnesium chain by measuring the root-mean-square charge radii of $^{21 - 32}$Mg, essentially covering the entire $\\textit{sd}$ shell. Our goal is to detect the structural changes, which in the neutron-deficient isotopes may originate from clustering, in a way similar to neon, and on the neutron-rich side would characterize the transition to the "island of inversion". We will combine, for the first time, the sensitive $\\beta$-detection technique with traditional fluorescence spectroscopy for isotope-shift measurements and in such a way gain access to the exotic species near the ${N}$ = 8 and ${N}$ = 20 shell closures.

  5. Atomic physics studies of highly charged ions on tokamaks using x-ray spectroscopy

    International Nuclear Information System (INIS)

    An overview is given of atomic physics issues which have been studied on tokamaks with the help resolution x-ray spectroscopy. The issues include the testing of model calculations predicting the excitation of line radiation, the determination of rate coefficients, and accurate atomic structure measurements. Recent research has focussed primarily on highly charged heliumlike (22 ≤ Z ≤ 28) and neonlike (34 ≤ Z ≤ 63) ions, and results are presented from measurements on the PLT and TFTR tokamaks. Many of the measurements have been aided by improved instrumental design and new measuring techniques. Remarkable agreement has been found between measurements and theory in most cases. However, in this review those areas are stressed where agreement is worst and where further investigations are needed. 19 refs., 13 figs., 2 tabs

  6. Synthesis, characterization and biological studies of a charge transfer complex: 2-Aminopyridinium-4-methylbenzenesulfonate

    Science.gov (United States)

    Vadivelan, Ganesan; Saravanabhavan, Munusamy; Murugesan, Venkatesan; Sekar, Marimuthu

    2015-06-01

    A single crystal charge transfer (CT) complex, 2-aminopyridinium-4-methylbenzenesulfonate (APTS) was synthesized and recrystallized by slow solvent evaporation solution growth method at room temperature. The complex has been characterized with the elemental analysis, UV-visible, infrared (IR), 1H and 13C nuclear magnetic resonance (NMR) spectra. Thermogravimetric (TG) and differential thermal analysis (DTA) were reported the thermal behaviour of the complex. Single crystal XRD studies showed that the orthorhombic nature of the crystal with space group Pbca. The biological activities of CT complex, such as DNA binding and antioxidant activity has been carried out. The results indicated that the compound could interact with DNA through intercalation and show significant capacity of scavenging with 2,2-diphenyl-2-picryl-hydrazyl (DPPH).

  7. Laboratory-Based Studies of Eating among Children and Adolescents.

    Science.gov (United States)

    Tanofsky-Kraff, Marian; Haynos, Ann F; Kotler, Lisa A; Yanovski, Susan Z; Yanovski, Jack A

    2007-01-01

    The prevalence of pediatric overweight has increased dramatically over the past three decades, likely due to changes in food intake as well as physical activity. Therefore, information examining eating patterns among children and adolescents is needed to illuminate which aspects of eating behavior require modification to prevent and treat pediatric overweight. Because child self-report and parent-report of children's eating habits are often inconsistent and limited by recall and other biases, laboratory-based studies in which food intake is observed and monitored have increased in number. Such studies offer objective and controlled methods of measuring and describing eating behaviors. However, to our knowledge, no publication exists that consolidates, reviews, and provides critical commentary on the literature to date in pediatric samples. In this paper, we review the literature of studies utilizing laboratory methods to examine eating behavior in samples ranging from birth through adolescence. Our review includes all relevant articles retrieved from the PubMed, Medline and PsychInfo search engines. Specifically, we examine meal-feeding studies conducted during the various developmental stages (infancy, preschool, middle childhood, and adolescence), with a focus on methodology. Included in our review are feeding studies related to dietary regulation, exposure and preference, as well as paradigms examining disordered eating patterns and their relationship to body composition. We have structured this review so that both consistent and inconsistent findings are presented by age group, and innovative methods of assessment are discussed in more detail. Following each section, we summarize findings and draw potential conclusions from the available data. We then discuss clinical implications of the research data and suggest directions for the next generation of studies of feeding behavior in children. PMID:19030122

  8. A PILOT STUDY OF CHILDREN'S TOTAL EXPOSURE TO PERSISTENT PESTICIDES AND OTHER PERSISTENT ORGANIC POLLUTANTS (CTEPP)

    Science.gov (United States)

    The Pilot Study of Children's Total Exposure to Persistent Pesticides and Other Persistent Organic Pollutants (CTEPP) investigated the aggregate exposures of 257 preschool children and their primary adult caregivers to pollutants commonly detected in their everyday environments. ...

  9. Specific language impairment in children with velocardiofacial syndrome : Four case studies

    NARCIS (Netherlands)

    Goorhuis-Brouwer, SM; Dikkers, FG; Robinson, PH; Kerstjens-Frederikse, WS

    2003-01-01

    Objective: To describe specific language impairment in four children with velocardiofacial syndrome (VCFS). Design: A descriptive, retrospective study of four cases. Setting: University Hospital Groningen, tertiary clinical care. Patients: Of 350 patients with cleft plate, 18 children were diagnosed

  10. Motor Milestone Development in Young Children with Autism Spectrum Disorders: An Exploratory Study

    Science.gov (United States)

    Liu, Ting

    2012-01-01

    This study aimed to determine if a sample of children currently diagnosed with autism spectrum disorders (ASDs) would have shown motor milestone delays before age three as compared to typically developing children. Given delays in motor skills, the study also strived to determine which specific skills might be delayed. Parents of 44 children who…

  11. Characteristics and Dental Experiences of Autistic Children in Saudi Arabia: Cross-Sectional Study

    Science.gov (United States)

    Murshid, Ebtissam Z.

    2011-01-01

    The purpose of this study is to report base line information about characteristics, and dental experiences of a group of autistic children in three major cities of Saudi Arabia. Most of the children (76.2%) included in the study were diagnosed with autism before the age of 5 years. More than half of the children (53.7%) had no previous dental…

  12. Psychosocial consequences for children of a parent with cancer : A pilot study

    NARCIS (Netherlands)

    Huizinga, GA; van der Graaf, WTA; Visser, A; Dijkstra, JS; Hoekstra-Weebers, JEHM

    2003-01-01

    When cancer is diagnosed in a parent, this may also have consequences for the children. The purpose of this pilot study was to gain more insight into the psychosocial consequences for children of a parent with cancer, from the perspective of both the children and their parents. For this study, 14 fa

  13. Mapping the Journey from Home to School: A Study on Children's Representation of Space

    Science.gov (United States)

    Thommen, Evelyne; Avelar, Silvania; Sapin, Veronique Zbinden; Perrenoud, Silvia; Malatesta, Dominique

    2010-01-01

    This paper describes a study conducted with 235 children from Brazil and Switzerland. The children, from 5 to 13 years of age, were asked to draw the journey they undertake every day from home to school. The purpose of the study is to understand the relationship between the cognitive development and map-drawing abilities of children in both…

  14. Family and Friend Relationships of Only Children: A Study of Adult Population in China.

    Science.gov (United States)

    Huang, Gary

    If personal networks of only children differ from those of children with siblings, then study of the different patterns of personal association is especially relevant to the understanding of social change in China, where the population of children without siblings is rapidly increasing. A study of these differential social networks used data…

  15. Analytical study for the charge-transfer complexes of losartan potassium

    Energy Technology Data Exchange (ETDEWEB)

    Darwish, Ibrahim A. [Department of Pharmaceutical Analytical Chemistry, Faculty of Pharmacy, Assiut University, Assiut 71526 (Egypt)]. E-mail: iadarwish@yahoo.com

    2005-09-06

    Studies were carried out, for the first time, to investigate the charge-transfer reactions of losartan potassium (LOS-K) as n-electron donor with the {sigma}-acceptor iodine and various {pi}-acceptors: 7,7,8,8-tetracyanoquinodimethane, 1,3,5-trinitrobenzene, 2,3-dichloro-5,6-dicyano-1,4-benzoquinone, p-chloranilic acid, tetracyanoethylene, 2,3,5,6-tetrabromo-1,4-benzoquinone, 2,3,5,6-tetrachloro-1,4-benzoquinone, and 2,4,7-trinitro-9-fluorenone. Different colored charge-transfer complexes and radical anions were obtained. Different variables affecting the reactions were studied and optimized. The formed complexes and the site of interaction were examined by UV-vis, IR, and {sup 1}H NMR techniques, and computational molecular modeling. The formation of the colored complexes were utilized in the development of simple, rapid and accurate spectrophotometric methods for the analysis of LOS-K in pure form as well as in its pharmaceutical tablets. Under the optimum reaction conditions, linear relationships with good correlation coefficients (0.9985-0.9998) were found between the absorbances and the concentrations of LOS-K in the range of 2-200 {mu}g ml{sup -1}. The limits of assays detection ranged from 0.61 to 19.65 {mu}g ml{sup -1}. No interference could be observed from the co-formulated hydrochlorothiazide (HCTZ), as well as from the additives commonly present in the tablets. The methods were successfully applied to the analysis of tablets from different manufacturers that contain LOS-K, alone or combined with HCTZ, with good accuracy and precision; the recovery percentages ranged from 98.96 {+-} 1.62% to 101.58 {+-} 1.29%. The results were compared favourably with the reported method.

  16. Clinical analysis of hypertension in children: An urban Indian study

    Directory of Open Access Journals (Sweden)

    Sunil K Kota

    2013-01-01

    Full Text Available Hypertension in children, although an uncommon entity, is associated with end-organ damage. We tried to study the clinical profile of hypertension in children presented to our hospital. The medical records from January 1990 to December 2010 of all children aged 18 years and younger with hypertension were studied. The patients were divided into four age groups (infants, pre-school age, school age and adolescents Presenting symptoms and other clinical parameters were thoroughly evaluated. The results were compared with previous studies on hypertension in children. A total of 135 patients were selected (male:female 103:32, with mean age of 0.4 ± 2.1 years (range: six months to 17 years. The most common age group affected was the adolescents group (42.9%. The most common clinical feature at presentation was dizziness (30.3%, followed by headache and chest discomfort (22.9%. Transient hypertension was detected in 34 patients (25.2%, and was most common in the adolescent age group, whereas sustained hypertension was noticed in 101 patients (74.8% and was the most common in the school age group (36/45, 80%. Forty-two patients (31.1% presented with hypertensive crisis. Nine patients were considered to have essential hypertension. The chief causes included chronic glomerulonephritis in 56 (41.5%, endocrine disorders in 21 (15.5%, obstructive uropathy in 16 (11.8%, reflux nephropathy in 12 (8.8% and renovascular disease in 5 (3.7%. Takayasu′s disease was the most common cause of renovascular hypertension. Coarctation of aorta was the most common cause of hypertension in infancy, being present in 40% of the cases. Hypertension in children may be easily underestimated but is a potentially life-threatening problem. Most of them are asymptomatic and a large chunk has an underlying etiology. Primary care clinicians should promptly identify patients with hypertension and treat them immediately and appropriately to prevent damage to the cardiovascular organs.

  17. Herpes Zoster in Healthy Children: A Retrospective Study

    Directory of Open Access Journals (Sweden)

    Birgül Tepe

    2016-06-01

    Full Text Available Objective: Herpes zoster is an acute dermatomal viral infection caused by the reactivation of varicella zoster virus. While it is commonly seen among elderly and immunocompromised individuals, it is rare in healthy children. The aim of this study was to evaluate the clinical features, treatment and complications of healthy children with herpes zoster. Methods: Thirty one patients aged between 0-16 years who were admitted to our clinic with the diagnosis of herpes zoster, between January 2014 and December 2014, were evaluated retrospectively for age, gender, month of admission, complaint, history of chickenpox infection or varicella vaccination, triggering factors, dermatomal involvement, complications and treatment. Results: Among 31 patients with diagnosis of herpes zoster, 19 were boys (61.3% and 12 were girls (38.7%. The mean of age was 9.12±4.4 years. Twenty patients had thoracic (64.5%, six had lumbar (19.4% and five had cervical involvements (16.2%. The most frequent symptoms were pruritus and pain, respectively. Six patients were administered topical treatment and 25 patients were treated with both systemic and topical treatments. Complication was not observed. Conclusion: Herpes zoster is also being encountered increasingly in healthy children nowadays. It is benign and generally no complications are observed. Incidence can vary because of geographic and socioeconomic differences like vaccination programs.

  18. STUDY ON ORIENTATION DISTURBANCE CORRECTION ON CHILDREN IN PRIMARY EDUCATION

    Directory of Open Access Journals (Sweden)

    Cristuţă Alina Mihaela

    2015-10-01

    Full Text Available Knowing your own body and the instrument is provided by the child knows himself. Child full manifested by body postures by attitudes, gestures or mimics, respectively through three ways of talking about the body and its functions, as follows: body "functional" movement whose functions are moving; body "active", whose function is to adapt to the world of objects; body "in the expression" participating in the encoding and decoding of media relations and creative subject. Orientation, organization and structuring of knowledge forms the major axes at school, both for normal baby and mentally impaired. Any objective relations phenomenon takes place in space and time, and a "timeless existence is as great an absurdity as an existence outside of space". The purpose of this research work is to correct and educate temporal-spatial orientation disorders in children in elementary school.For a better organization of research, we started from the assumption such that: use of additional intervention in children in primary education based on educational exercises temporal-spatial orientation, psychomotor component achieves this correction. Research methods used were determined according to the research objectives, such bibliographic study method was used, test method, statistical and mathematical method and graphical method. Following research paper concluded that by implementing intervention programs specific application can correct and educate temporal-spatial orientation disorders in children in primary education, so by communicating results, to implement specific intervention programs and in physical education classes in the school curriculum at this age.

  19. Meningiomas in children: A study of 18 cases

    Directory of Open Access Journals (Sweden)

    Nirav Mehta

    2009-01-01

    Full Text Available Background : Intracranial meningiomas are rare tumors in children accounting for 0.4-4.6% of all primary brain tumors in the age group of 0-18 years. Objective : To retrospectively analyze the epidemiological profile, clinical features, radiological findings, type of excision, histopathological findings, and overall management profile of these patients. Materials and Methods : Eighteen consecutive cases of meningioma in patients under 18 years of age admitted and operated at our institute between the years 1974-2005 were included in this study. Results : The mean age of patient at presentation to our hospital was 12.81 years. The male to female ratio was 1.57:1. The median preoperative duration of symptoms was 1.2 years. An increased incidence was seen in patients with neurofibromatosis. Intraventricular and skull base locations were common. Total tumor excision was achieved in all cases. Conclusion : A higher incidence of atypical and aggressive meningiomas is seen in children. Children with complete resection and a typical benign histology have a good prognosis.

  20. Parasomnias and sleep disordered breathing in Caucasian and Hispanic children – the Tucson children's assessment of sleep apnea study

    Directory of Open Access Journals (Sweden)

    Fregosi Ralph F

    2004-04-01

    Full Text Available Abstract Background Recent studies in children have demonstrated that frequent occurrence of parasomnias is related to increased sleep disruption, mental disorders, physical harm, sleep disordered breathing, and parental duress. Although there have been several cross-sectional and clinical studies of parasomnias in children, there have been no large, population-based studies using full polysomnography to examine the association between parasomnias and sleep disordered breathing. The Tucson Children's Assessment of Sleep Apnea study is a community-based cohort study designed to investigate the prevalence and correlates of objectively measured sleep disordered breathing (SDB in pre-adolescent children six to 11 years of age. This paper characterizes the relationships between parasomnias and SDB with its associated symptoms in these children. Methods Parents completed questionnaires pertaining to their child's sleep habits. Children had various physiological measurements completed and then were connected to the Compumedics PS-2 sleep recording system for full, unattended polysomnography in the home. A total of 480 unattended home polysomnograms were completed on a sample that was 50% female, 42.3% Hispanic, and 52.9% between the ages of six and eight years. Results Children with a Respiratory Disturbance Index of one or greater were more likely to have sleep walking (7.0% versus 2.5%, p p p Conclusions In this population-based cohort study, pre-adolescent school-aged children with SDB experienced more parasomnias than those without SDB. Parasomnias were associated with a higher prevalence of other sleep disturbances and learning problems. Clinical evaluation of children with parasomnias should include consideration of SDB.

  1. Mothers Reading Children's Books to Preschoolers. A Greek study

    Directory of Open Access Journals (Sweden)

    Natsiopoulou T.

    2008-01-01

    Full Text Available This article presents the results of a Greek study on the extratextual interactions between mothersand their preschoolers during repeated readings of the same storybook. Eleven (11 mothers with tertiary andeleven mothers (11 with secondary education read out loud the book “The three little wolves and the big bad pig”three times, once every three days and the fourth time they narrated it to their 4–5 year olds. All four times, whichwere recorded by the parents, were done in one-to-one settings, in their homes. Mothers with a tertiary educationduring the first reading made more extratextual interactions overall, as well as more verbal exchanges in thelow-level abstraction categories: organizing the reading, names, clarifying, and in high-level abstraction categoryrelating the story to real life. Mothers with secondary education during the second reading made more extratextualinteractions overall, as well as more verbal exchanges in the low-level abstraction categories: clarifying and attention.Both categories of mothers progressively decreased their insertions with subsequent readings. During the firsttwo readings mothers with tertiary education made more extratextual interactions overall, as well as more low- andhigh-level abstraction insertions, than mothers with secondary education. Children whose mothers had a tertiaryeducation made more insertions overall, including more low- and high-level abstraction extratextual interactions,than the other preschoolers. It was found that all mothers and children had a high percentage of low-level abstractionextratextual interactions. More specifically, this was noted in the following categories for mothers: clarifying,feedback and names; for children: clarifying and asking for clarification. Nevertheless, mothers with a tertiary educationand their children made more high-level abstract extratextual interactions in the category relating the storyto real life than the others.

  2. Swimming pool attendance is related to asthma among atopic school children: a population-based study

    OpenAIRE

    Andersson, Martin; Hedman, Linnéa; Nordberg, Gunnar; Forsberg, Bertil; Eriksson, Kåre; Rönmark, Eva

    2015-01-01

    Background: By-products of water disinfectants have been suggested to cause asthma, especially in atopic children. However, studies on indoor swimming pool attendance and asthma in children have presented conflicting results. The present study examined the relationship between indoor swimming pool attendance and asthma among sensitized and non-sensitized children aged 11-12 years. Methods: An extended ISAAC questionnaire was sent to the families of all children attending fifth or sixth grade,...

  3. Growth trajectories in the children of mothers with eating disorders: a longitudinal study

    OpenAIRE

    Easter, A.; Howe, L D; Tilling, K; Schmidt, U.; Treasure, J.; Micali, N.

    2014-01-01

    Objective The aim of this study was to examine longitudinal patterns of growth trajectories in children of women with eating disorders (ED): anorexia nervosa (AN) and bulimia nervosa (BN). Design Prospective longitudinal birth cohort; Avon Longitudinal Study of Parents and Children (ALSPAC). Setting South West England, UK. Participants The sample consisted of women and their children (n=10 190) from ALSPAC. Patterns of growth among children of women reporting a history of AN (n=137), BN (n=16...

  4. Motor deficits in children with autism spectrum disorder: A cross-syndrome study

    OpenAIRE

    McPhillips, Martin; Finlay, Jennifer; Bejerot, Susanne; Hanley, Mary

    2014-01-01

    Recent research suggests that children with autism spectrum disorder (ASD) experience some level of motor difficulty, and that this may be associated with social communication skills. However, other studies show that children with language impairments, but without the social communication problems, are at risk of motor difficulties as well. The aim of the present study was to determine if children with ASD have syndrome specific motor deficits in comparison to children with specific language ...

  5. Surface photovoltage studies of environmental influence on charge dynamics in nanostructured silicon

    Science.gov (United States)

    Chapagain, Puskar Raj

    Optoelectronic properties of nanoscale materials are significantly affected by their surfaces because of the presence of intrinsic and extrinsic electronic states in the bandgap. Thermally or optically driven charge exchange between the bulk and these states directly affects the surface band bending of these materials. Physisorption, chemisorption or desorption of environmental species at the surface also bring in additional modifications to the surface electronic structure, thereby, changing the surface potential barrier. The focus of this work was to investigate the influence of the environmental conditions on the surface band bending in nanoporous silicon (NPS), as well as some other nanostructured materials, using transient surface photovoltage---a non-destructive and highly surface-sensitive experimental probe. The potential barrier in NPS was monitored in a wide range of pressures, going down to high vacuum, and in a variety of gases. Due to the different rates of physisorption and chemisorption processes, we observed a coexistence of multiple components in the SPV transients occurring on different time scales and under different ambient conditions. We suggested a model elucidating the roles of intrinsic or extrinsic states in the surface transport properties of NPS. The importance of results is discussed in relation to potential applications of the studied materials in optoelectronic gas sensors. In order to distinguish between different surface charge transport processes affected by adsorption/desorption, we employed monochromatic illumination using several different wavelengths for selective excitation of these processes and compared these results with the ones observed for a polychromatic illumination containing both super- and sub-bandgap wavelengths. The scaling of transient SPV onset slopes in NPS vs. the excitation intensity was found to deviate from the linear dependence commonly observed in conventional bulk semiconductors. Considering drift- and

  6. Economic Viability Study of an On-Road Wireless Charging System with a Generic Driving Range Estimation Method

    Directory of Open Access Journals (Sweden)

    Aditya Shekhar

    2016-01-01

    Full Text Available The economic viability of on-road wireless charging of electric vehicles (EVs strongly depends on the choice of the inductive power transfer (IPT system configuration (static or dynamic charging, charging power level and the percentage of road coverage of dynamic charging. In this paper, a case study is carried out to determine the expected investment costs involved in installing the on-road charging infrastructure for an electric bus fleet. Firstly, a generic methodology is described to determine the driving range of any EV (including electric buses with any gross mass and frontal area. A dynamic power consumption model is developed for the EV, taking into account the rolling friction, acceleration, deceleration, aerodynamic drag, regenerative braking and Li-ion battery behavior. Based on the simulation results, the linear dependence of the battery state of charge (SoC on the distance traveled is proven. Further, the impact of different IPT system parameters on driving range is incorporated. Economic implications of a combination of different IPT system parameters are explored for achieving the required driving range of 400 km, and the cost optimized solution is presented for the case study of an electric bus fleet. It is shown that the choice of charging power level and road coverage are interrelated in the economic context. The economic viability of reducing the capacity of the on-board battery as a trade-off between higher transport efficiency and larger on-road charging infrastructure is presented. Finally, important considerations, like the number of average running buses, scheduled stoppage time and on-board battery size, that make on-road charging an attractive option are explored. The cost break-up of various system components of the on-road charging scheme is estimated, and the final project cost and parameters are summarized. The specific cost of the wireless on-road charging system is found to be more expensive than the conventional

  7. Approaches to Children's Exposure Assessment: Case Study with Diethylhexylphthalate (DEHP).

    Science.gov (United States)

    Ginsberg, Gary; Ginsberg, Justine; Foos, Brenda

    2016-01-01

    Children's exposure assessment is a key input into epidemiology studies, risk assessment and source apportionment. The goals of this article are to describe a methodology for children's exposure assessment that can be used for these purposes and to apply the methodology to source apportionment for the case study chemical, diethylhexylphthalate (DEHP). A key feature is the comparison of total (aggregate) exposure calculated via a pathways approach to that derived from a biomonitoring approach. The 4-step methodology and its results for DEHP are: (1) Prioritization of life stages and exposure pathways, with pregnancy, breast-fed infants, and toddlers the focus of the case study and pathways selected that are relevant to these groups; (2) Estimation of pathway-specific exposures by life stage wherein diet was found to be the largest contributor for pregnant women, breast milk and mouthing behavior for the nursing infant and diet, house dust, and mouthing for toddlers; (3) Comparison of aggregate exposure by pathways vs biomonitoring-based approaches wherein good concordance was found for toddlers and pregnant women providing confidence in the exposure assessment; (4) Source apportionment in which DEHP presence in foods, children's products, consumer products and the built environment are discussed with respect to early life mouthing, house dust and dietary exposure. A potential fifth step of the method involves the calculation of exposure doses for risk assessment which is described but outside the scope for the current case study. In summary, the methodology has been used to synthesize the available information to identify key sources of early life exposure to DEHP. PMID:27376320

  8. Study of the top quark electric charge at the CDF experiment

    Energy Technology Data Exchange (ETDEWEB)

    Bartos, Pavol [Comenius Univ., Bratislava (Slovakia)

    2011-01-01

    We report on the measurement of the top quark electric charge using the jet charge tagging method on events containing a single lepton collected by the CDF II detector at Fermilab between February 2002 and February 2010 at the center-of-mass energy √s = 1.96 TeV. There are three main components to this measurement: determining the charge of the W (using the charge of the lepton), pairing the W with the b-jet to ensure that they are from the same top decay branch and finally determining the charge of the b-jet using the Jet Charge algorithm. We found, on a sample of 5.6 fb-1 of data, that the p-value under the standard model hypothesis is equal to 13.4%, while the p-value under the exotic model hypothesis is equal to 0.014%. Using the a priori criteria generally accepted by the CDF collaboration, we can say that the result is consistent with the standard model, while we exclude an exotic quark hypothesis with 95% confidence. Using the Bayesian approach, we obtain for the Bayes factor (2ln(BF)) a value of 19.6, that favors very strongly the SM hypothesis over the XM one. The presented method has the highest sensitivity to the top quark electric charge among the presented so far top quark charge analysis.

  9. Study of the top quark electric charge at the CDF experiment

    Energy Technology Data Exchange (ETDEWEB)

    Bartos, Pavol; /Comenius U.

    2011-09-01

    We report on the measurement of the top quark electric charge using the jet charge tagging method on events containing a single lepton collected by the CDF II detector at Fermilab between February 2002 and February 2010 at the center-of-mass energy {radical}s = 1.96 TeV. There are three main components to this measurement: determining the charge of the W (using the charge of the lepton), pairing the W with the b-jet to ensure that they are from the same top decay branch and finally determining the charge of the b-jet using the Jet Charge algorithm. We found, on a sample of 5.6 fb{sup -1} of data, that the p-value under the standard model hypothesis is equal to 13.4%, while the p-value under the exotic model hypothesis is equal to 0.014%. Using the a priori criteria generally accepted by the CDF collaboration, we can say that the result is consistent with the standard model, while we exclude an exotic quark hypothesis with 95% confidence. Using the Bayesian approach, we obtain for the Bayes factor (2ln(BF)) a value of 19.6, that favors very strongly the SM hypothesis over the XM one. The presented method has the highest sensitivity to the top quark electric charge among the presented so far top quark charge analysis.

  10. Development and comparative study of different nanofiltration membranes for recovery of highly charged large ions

    NARCIS (Netherlands)

    Chowdhury, S. Roy; Elshof, ten J.E.; Benes, N.E.; Keizer, K.

    2002-01-01

    The development of membranes for polyoxometalate (POM) recycling based on charge or size effects is described. POM recycling via nanofiltration with surface charge membranes is a new approach. From the properties of solute—membrane interaction three different kinds of nanofiltration membranes have b

  11. Far-Infrared Study of the Charge Density Wave in Tetrathiofulvalene Tetracyanoquinodimethane (TTF-TCNQ)

    DEFF Research Database (Denmark)

    Tanner, D. B.; Cummings, K. D.; Jacobsen, Claus Schelde

    1981-01-01

    Detailed far-infrared measurements at temperatures from 25 to 300 K provide strong support for a charge-density-wave mechanism for the dc conductivity and microwave dielectric constant of tetrathiafulvalene tetracyanoquinodimethane (TTF-TCNQ). At low temperatures the charge-density wave is pinned...

  12. Spectrophotometric study of the charge transfer complexation of some porphyrin derivatives as electron donors with tetracyanoethylene

    Science.gov (United States)

    El-Zaria, Mohamed E.

    2008-01-01

    Charge transfer complexes (CTC) of 5,10,15,20-tetraphenylporphyrin (TPP), 5,10,15,20-tetra(4-tolyl)porphyrin (TTP), 5,10,15,20-tetra(4-methoxyphenyl)porphyrin (TMP), Zn-5,10,15,20-tetraphenylporphyrin (Zn-TPP), and Zn-5,10,15,20-tetra(4-tolyl)porphyrin (Zn-TTP) with tetracyanoethylene (TCNE) have been studied at various temperatures in CH 2Cl 2 and CCl 4. The data are discussed in terms of equilibrium constant ( KCT), molar extinction coefficient ( ɛCT), thermodynamic standard reaction quantities (Δ G°, Δ H° and Δ S°), oscillator strength ( f), and transition dipole moment ( μ). The spectrum obtained for TPP/TCNE, TTP/TCNE, and TMP/TCNE systems shows two main absorption bands at 475 and 690 nm, which are not due to the absorption of any of the reactants. These bands are characteristic of an intermolecular charge transfer involving the overlap of the lowest unoccupied molecular orbital (LUMO) of the acceptor with the highest occupied molecular orbital (HOMO) of the donor. The results reveal that the interaction between the donors and acceptor is due to π-π * transitions by the formation of radical ion pairs. The stoichiometry of the complexes was found to be 1:1 ratio by the Job and straight line methods between donors and acceptor with the maximum absorption bands at wavelengths of 475 and 690 nm. The observed data show salvation effects on the spectral and thermodynamics properties of CTC. The ionization potential of the donors and the dissociation energy of the CTC were also determined and are found to be constant.

  13. A systematic study of neutral and charged 3d-metal trioxides and tetraoxides

    Science.gov (United States)

    Pradhan, Kalpataru; Gutsev, Gennady L.; Weatherford, Charles A.; Jena, Purusottam

    2011-04-01

    Using density functional theory with generalized gradient approximation, we have performed a systematic study of the structure and properties of neutral and charged trioxides (MO3) and tetraoxides (MO4) of the 3d-metal atoms. The results of our calculations revealed a number of interesting features when moving along the 3d-metal series. (1) Geometrical configurations of the lowest total energy states of neutral and charged trioxides and tetraoxides are composed of oxo and/or peroxo groups, except for CuO3- and ZnO3- which possess a superoxo group, CuO4+ and ZnO4+ which possess two superoxo groups, and CuO3+, ZnO3+, and ZnO4- which possess an ozonide group. While peroxo groups are found in the early and late transition metals, all oxygen atoms bind chemically to the metal atom in the middle of the series. (2) Attachment or detachment of an electron to/from an oxide often leads to a change in the geometry. In some cases, two dissociatively attached oxygen atoms combine and form a peroxo group or a peroxo group transforms into a superoxo group and vice versa. (3) The adiabatic electron affinity of as many as two trioxides (VO3 and CoO3) and four tetraoxides (TiO4, CrO4, MnO4, and FeO4) are larger than the electron affinity of halogen atoms. All these oxides are hence superhalogens although only VO3 and MnO4 satisfy the general superhalogen formula.

  14. Urolithiasis in Tunisian children: A study of 100 cases

    Directory of Open Access Journals (Sweden)

    Alaya Akram

    2009-01-01

    Full Text Available The aim of this study is to assess the clinical and biological characteristics of renal stone disease among children living in the coastal region of Tunisia. This retrospective multi-center study included 100 children under the age of 16 years, who presented with urinary stones. The patients′ charts were reviewed with regard to age at diagnosis, sex, history and physical exami-nation as well as laboratory and radiologic findings. Stone analysis was performed by infrared spec-trophotometry. The male/female sex ratio was 1.5 to 1. The clinical presentation of this pathology was dominated by dysuria. Stones were located in the upper urinary tract in 76 cases (76%. A total of 13% of the study subjects had positive urine cultures. Metabolic investigations were performed in all patients and were normal in 80 cases. Whewellite (calcium oxalate was found in 77 stones (77.0%. Stone section was made of whewellite in 69.0% of cases and ammonium urate in 47.0%. Struvite stones were more frequently seen in the lower urinary tract. Our study suggests that the epidemiological profile of renal stones in Tunisia has changed towards a predominance of calcium oxalate stones and upper tract location. Also, the male predominance of pediatric urolithiasis is becoming less obvious in Tunisia

  15. Mesiodens: A clinical and radiographic study in children

    Directory of Open Access Journals (Sweden)

    S Mukhopadhyay

    2011-01-01

    Full Text Available Background: A mesiodens is a supernumerary tooth located in the palatal midline between the two maxillary central incisors. The overall prevalence varies between 0.15 and 1.9%. The present study aimed to evaluate the epidemiological characteristics of mesiodens in the pediatric population. Materials and Methods: A longitudinal prospective study was carried out in 7932 children to determine the prevalence of mesiodens. The following data were also recorded: age, sex, shape, sagittal position, orientation, eruption status, number and complications caused by mesiodens. Results: The prevalence of mesiodens in the present study was 0.8%. The sex ratio was 1.78:1, favoring boys. The majority of mesiodens (67.9% were conical in shape, followed by the supplemental (17.9 and tuberculate (14.1% types. 71.8% of the mesiodens were palatally placed, 25.6% erupted on the arch and 2.6% were labially positioned. A majority of the mesiodens (62.8% were vertically aligned. Inverted and horizontal positions were observed in 30.8% and 6.4% of the cases. Most of the mesiodens (53.8% were impacted, and 14 children had two mesiodens. Most of the mesiodens were associated with complications, and only 26.9% were asymptomatic. Conclusions: The prevalence of mesiodens was 0.8% .Conical shape, palatal position and vertical orientation were common characteristic observations in the study.

  16. Radiation doses to children during modified barium swallow studies

    Energy Technology Data Exchange (ETDEWEB)

    Weir, Kelly A. [University of Queensland, Discipline of Paediatrics and Child Health, School of Medicine, Herston, Queensland (Australia); McMahon, Sandra M. [SpeechNet Speech Pathology Services, Brisbane (Australia); Long, Gillian; Bunch, Judith A. [Royal Children' s Hospital, Department of Medical Imaging, Herston (Australia); Pandeya, Nirmala [Queensland Institute of Medical Research, Herston (Australia); Coakley, Kerry S. [Biomedical Technology Services, Royal Brisbane and Women' s Hospital, Herston (Australia); Chang, Anne B. [Royal Children' s Hospital, Department of Respiratory Medicine, Herston (Australia)

    2007-03-15

    There are minimal data on radiation doses to infants and children undergoing a modified barium swallow (MBS) study. To document screening times, dose area product (DAP) and effective doses to children undergoing MBS and to determine factors associated with increased screening times and effective dose. Fluoroscopic data (screening time, DAP, kVp) for 90 consecutive MBS studies using pulse fluoroscopy were prospectively recorded; effective dose was calculated and data were analyzed for effects of behavior, number of swallow presentations, swallowing dysfunction and medical problems. Mean effective dose for the entire group was 0.0826 {+-} 0.0544 mSv, screening time 2.48 {+-} 0.81 min, and DAP 28.79 {+-} 41.72 cGy cm{sup 2}. Significant differences were found across three age groups ({<=}1.0, >1.0-3.0 and >3.0 years) for effective dose (mean 0.1188, 0.0651 and 0.0529 mSv, respectively; P < 0.001), but not for screening time or DAP. Effective dose was correlated with screening time (P = 0.007), DAP (P < 0.001), number of swallow presentations (P = 0.007), lower age (P = 0.017), female gender (P = 0.004), and height (P < 0.001). Screening time was correlated with total number of swallow presentations (P < 0.001) and DAP (P < 0.001). Screening times, DAP, effective dose, and child and procedural factors associated with higher effective doses are presented for children undergoing MBS studies. (orig.)

  17. Radiation doses to children during modified barium swallow studies

    International Nuclear Information System (INIS)

    There are minimal data on radiation doses to infants and children undergoing a modified barium swallow (MBS) study. To document screening times, dose area product (DAP) and effective doses to children undergoing MBS and to determine factors associated with increased screening times and effective dose. Fluoroscopic data (screening time, DAP, kVp) for 90 consecutive MBS studies using pulse fluoroscopy were prospectively recorded; effective dose was calculated and data were analyzed for effects of behavior, number of swallow presentations, swallowing dysfunction and medical problems. Mean effective dose for the entire group was 0.0826 ± 0.0544 mSv, screening time 2.48 ± 0.81 min, and DAP 28.79 ± 41.72 cGy cm2. Significant differences were found across three age groups (≤1.0, >1.0-3.0 and >3.0 years) for effective dose (mean 0.1188, 0.0651 and 0.0529 mSv, respectively; P < 0.001), but not for screening time or DAP. Effective dose was correlated with screening time (P 0.007), DAP (P < 0.001), number of swallow presentations (P = 0.007), lower age (P = 0.017), female gender (P = 0.004), and height (P < 0.001). Screening time was correlated with total number of swallow presentations (P < 0.001) and DAP (P < 0.001). Screening times, DAP, effective dose, and child and procedural factors associated with higher effective doses are presented for children undergoing MBS studies. (orig.)

  18. Comorbidities in ADHD children treated with methylphenidate: a database study

    Directory of Open Access Journals (Sweden)

    Kraut Angela A

    2013-01-01

    conditions were rare in the studied age range, but still higher among children who received MPH than in the control group. Results show that in a substantial subgroup of patients, comorbidities require a thorough weighting of possible risks of MPH medication against the risks of untreated ADHD.

  19. Antiamoebic Chemoprophylaxis Using Quinfamide in Children: A Comparative Study

    Directory of Open Access Journals (Sweden)

    Nicolas Padilla

    2002-01-01

    Full Text Available This study sought to examine whether the administration of quinfamide at 3- or 6-month intervals diminished the frequency of Entamoeba histolytica cysts in stool samples compared to controls. The prospective, longitudinal, randomized, single-blind study examined children from six primary schools in Celaya and Neutla, Guanajuato. Of the 1,524 students in these schools, we selected participants for the study as follows: Children were included in the study if their parents agreed in writing to the study and if the children demonstrated evidence of E. histolytica cysts after a parasitoscopic analysis by concentration (PSC in three samples over consecutive days using Faust’s method. Those included in the study received a single 4.3-g/kg dose of quinfamide, and we performed PSC on days 5, 6, and 7 following dose administration to examine whether quinfamide had affected the presence of the cysts. The study participants who tested negative for cysts were divided into three groups: Group 1 had 102 patients who underwent quinfamide treatment and three CPS analyses after the 12 months of the study; Group 2 had 98 subjects who underwent the quinfamide treatment and three CPS analyses at months 3, 6, 9, and 12 after their entrance into the study; and Group 3 had 102 patients, who underwent the quinfamide treatment and series of three CPS analyses at months 6 and 12 of the study. All participants received the dose of quinfamide after providing stool samples and after a clinical gastrointestinal history was obtained. Further clinical gastrointestinal data were collected 5 days after the quintamide dose was administered. We used EpiInfo 6.0 for statistical analysis, calculating X2 and p values for the clinical data and the CPS data after the 12 months concluded. Of the initial samples of 1,524 subjects, 308 (20.2% had Entamoebic cysts. Of these, six were further eliminated because they did not meet the inclusion requirements. At the conclusion of the study

  20. [The mother figure of children with malformations. A phenomenological study].

    Science.gov (United States)

    Pinheiro, M C

    1997-01-01

    The theme of this research refers to children suffering congenital malformation through an analysis of their mothers' reactions in dealing with such a situation. It deals with a descriptive study along the qualitative line through the phenomenological approach. In order to attain that purpose, interviews were made and data collected. The analysis was built under the view of meaning, the orientation of those mothers, i.e. the outlook of the world from their perspective, which was tracked from the meanings (units of meaning) to actual sense based on the philosophical insight of Dr. Martin Heidegger, aiming at characterizing the mother-being in her daily life. PMID:9775933

  1. Molecular study of developmental sex disorders in children

    OpenAIRE

    Soheir S. AboElella; Maha A.M. Tawfik; Wafaa moustafa M. Abo El-fotoh

    2015-01-01

    Background: Sex determination and differentiation in humans are processes that involve the interaction of several genes such as SRY, SOX9 genes which are important in the development of the male genital system. Also NR5A1 gene plays an important role in the development of gonads and the adrenal glands. Aim of the study include clinical assessment of children with disorders of sex development, molecular analyses for SRY, SOX9 and NR5A1 genes and genetic counseling for the patients and their fa...

  2. Children Rights in Social Studies Curricula in Elementary Education: A Comparative Study

    Science.gov (United States)

    Merey, Zihni

    2012-01-01

    Social studies classes educate students as citizens who are expected to adopt democratic values and apply their information and richness to their life. Social studies classes are the ones that include human rights education in the first place. The purpose of this study is to make a comparison of inclusion levels of children's rights issues in…

  3. Systematic identification and intervention for reading difficulty: case studies of children with EAL.

    Science.gov (United States)

    Fawcett, A J; Lynch, L

    2000-01-01

    Literacy underpins education. There is now very widespread concern over standards of literacy for children from multi-cultural backgrounds, who are learning English as a second or subsequent language, and who may have special educational needs. Research evidence suggests that the earlier children's difficulties can be identified, the more effective (and cost-effective) intervention will be, provided that the intervention is tailored to the child's abilities and skills. Nicolson and Fawcett have developed systematic procedures for identifying children at risk for reading difficulty, together with systematic teaching strategies to overcome reading difficulty. In this paper we present case studies of children with EAL (English as an additional language) drawn from a controlled study using computer interventions with secondary school children. Our findings indicate that children with EAL may be more resistant to remediation than some children with learning difficulties. The prognosis is more problematic for children with both EAL and dyslexia. PMID:10840507

  4. Experimental study of the fragmentation of water clusters induced by multiply charged ions

    International Nuclear Information System (INIS)

    This work deals with the fragmentation of neutral water clusters induced by collisions with slow and swift multiply charged ions. Strong projectile charge dependence is found for all of the fragmentation patterns in the charge transfer regime. When increasing the projectile charge (from q = 2 to q = 20), we observe a modification of the scenario of the fragmentation dynamics with a transition from a partial dissociation to a full cluster explosion. We observe that water clusters are more strongly heated by Xe20+ than by He2+. These results are in contrast to the generally accepted idea that highly charged ions are an efficient tool to ionize the target at large impact parameters without a huge amount of energy transfer. The results obtained with high energy projectiles Ni25+ i.e. in the ionization regime, are very similar than those obtained with low velocity Xe20+ i.e. in the charge transfer regime. These results suggest that even if the primary mechanism is different, the 'same' electrons are into play and ejected from the target. In this work, we have also produced size-selected protonated water clusters by the coupling of an Electro-Spray Ion source together with a quadrupole mass filter. In order to perform, in the next future, collisions between these size-selected water clusters and projectile ions, we designed and realized a new experimental device which allows us to produce intense singly charged ions beams. (author)

  5. Improvement of fine motor skills in children with visual impairment: an explorative study

    NARCIS (Netherlands)

    Reimer, A.M.; Cox, R.F.; Nijhuis-Van der Sanden, M.W.G.; Boonstra, F.N.

    2011-01-01

    In this study we analysed the potential spin-off of magnifier training on the fine-motor skills of visually impaired children. The fine-motor skills of 4- and 5-year-old visually impaired children were assessed using the manual skills test for children (6-12 years) with a visual impairment (ManuVis)

  6. Phonological Neighborhood Density in the Picture Naming of Young Children Who Stutter: Preliminary Study

    Science.gov (United States)

    Arnold, Hayley S.; Conture, Edward G.; Ohde, Ralph N.

    2005-01-01

    The purpose of this study was to assess the effect of phonological neighborhood density on the speech reaction time (SRT) and errors of children who do and do not stutter during a picture-naming task. Participants were nine 3-5-year-old children who stutter (CWS) matched in age and gender to nine children who do not stutter (CWNS). Initial…

  7. Working Memory, Attention, and Mathematical Problem Solving: A Longitudinal Study of Elementary School Children

    Science.gov (United States)

    Swanson, H. Lee

    2011-01-01

    The role of working memory (WM) in children's growth in mathematical problem solving was examined in a longitudinal study of children (N = 127). A battery of tests was administered that assessed problem solving, achievement, WM, and cognitive processing (inhibition, speed, phonological coding) in Grade 1 children, with follow-up testing in Grades…

  8. Multiracial Children and Poverty: Evidence from the Early Childhood Longitudinal Study of Kindergartners

    Science.gov (United States)

    Bratter, Jenifer; Kimbro, Rachel Tolbert

    2013-01-01

    Despite the recent growth in multiracial children among American children, we know very little about their well-being. Using the Early Childhood Longitudinal Study, Kindergarten Class (N?=?17,706), we evaluated the likelihood of living in poverty and near poverty for multiracial and monoracial children. Most multiracial groups have poverty or near…

  9. Effects of a physical activity intervention study in obese/overweight children adipose tissue

    OpenAIRE

    Lopes, Vítor P.; Vasques, Catarina; D.C. Gomes; Correia, Teresa

    2009-01-01

    The worldwide increase of obesity in children claim for urgent measures in several instances. One of the keys measures is to increase the children habitual physical activity (PA). The propose of this study is to analyze the effects of an PA intervention program in the children adipose tissue.

  10. A Case Study of Three Children's Original Interpretations of the Moon's Changing Appearance

    Science.gov (United States)

    Wilhelm, Jennifer

    2009-01-01

    A case study of three children was conducted to shed light on the process that children undergo in developing their understanding of physical phenomena. Using the notion of spontaneous construction and its relationship with school learning of scientific concepts, children's early thoughts of the moon's appearance were explored. Research questions…

  11. Traumatic Responding in Children Exposed to Domestic Violence: A Cross-Cultural Study.

    Science.gov (United States)

    Lehmann, Peter; Elliston, Ellen J.

    2001-01-01

    A study examined posttraumatic stress disorder in Mexican, Mexican American, and non-Mexican American children exposed to domestic violence. Surveys of 68 mothers with children in shelters in Mexico and Texas revealed no ethnic differences in children's overall trauma symptoms. Mothers' experience of physical and sexual abuse predicted greater…

  12. Perceived Racism and Discrimination in Children and Youths: An Exploratory Study

    Science.gov (United States)

    Pachter, Lee M.; Bernstein, Bruce A.; Szalacha, Laura A.; Garcia Coll, Cynthia

    2010-01-01

    Racism may be a factor contributing to poor health and health care disparities in minority children through multiple mechanisms, including effects on psychological and physical well-being. Little is known about the experiences of racism that children encounter in their lives. This study describes the occurrences of perceived racism in children,…

  13. Study of Level of Stress in the Parents of Children with Attention-Deficit/Hyperactivity Disorder

    Science.gov (United States)

    Sethi, Sujata; Gandhi, Raghu; Anand, Vidhu

    2012-01-01

    Background: Parents who have children with attention-deficit hyperactivity disorder (ADHD) often experience high level of stress related to caring for their children. But not much research has been conducted in this area in India. This study aimed to assess the stress of parenting children with ADHD. Methods: This is a clinic based comparative…

  14. Improvement of fine motor skills in children with visual impairment: An explorative study

    NARCIS (Netherlands)

    Reimer, A.M.; Cox, R.F.A.; Nijhuis-Van der Sanden, M.W.G.; Boonstra, F.N.

    2011-01-01

    In this study we analysed the potential spin-off of magnifier training on the fine-motor skills of visually impaired children. The fine-motor skills of 4- and 5-year-old visually impaired children were assessed using the manual skills test for children (6-12 years) with a visual impairment (ManuVis)

  15. Timing of Mother and Child Depression in a Longitudinal Study of Children at Risk.

    Science.gov (United States)

    Hammen, Constance; And Others

    1991-01-01

    Examined temporal associations of diagnoses in mothers and children in 3-year longitudinal study of unipolar, bipolar, and comparison women and their 8- to 16-year-old children. Found significant temporal association between mother and child diagnoses, especially in unipolar families, and most children who experienced major depressive episode did…

  16. Friends' Responses to Children's Disclosure of an Achievement-Related Success: An Observational Study

    Science.gov (United States)

    Altermatt, Ellen Rydell; Ivers, Ivy E.

    2011-01-01

    This study examined social support processes in the context of positive events. The conversations of fourth-grade through sixth-grade focal children and their friends (N = 116) were observed after focal children outperformed their friend on an achievement-related task. Changes in focal children's performance-related positive affect from…

  17. Air Pollution, Cognitive Deficits and Brain Abnormalities: A Pilot Study with Children and Dogs

    Science.gov (United States)

    Calderon-Garciduenas, Lilian; Mora-Tiscareno, Antonieta; Ontiveros, Esperanza; Gomez-Garza, Gilberto; Barragan-Mejia, Gerardo; Broadway, James; Chapman, Susan; Valencia-Salazar, Gildardo; Jewells, Valerie; Maronpot, Robert R.; Henriquez-Roldan, Carlos; Perez-Guille, Beatriz; Torres-Jardon, Ricardo; Herrit, Lou; Brooks, Diane; Osnaya-Brizuela, Norma; Monroy, Maria E.; Gonzalez-Maciel, Angelica; Reynoso-Robles, Rafael; Villarreal-Calderon, Rafael; Solt, Anna C.; Engle, Randall W.

    2008-01-01

    Exposure to air pollution is associated with neuroinflammation in healthy children and dogs in Mexico City. Comparative studies were carried out in healthy children and young dogs similarly exposed to ambient pollution in Mexico City. Children from Mexico City (n:55) and a low polluted city (n:18) underwent psychometric testing and brain magnetic…

  18. A Longitudinal Study of Pragmatic Language Development in Three Children with Cochlear Implants

    Science.gov (United States)

    Dammeyer, Jesper

    2012-01-01

    Research has shown how cochlear implants (CIs), in children with hearing impairments, have improved speech perception and production, but very little is known about the children's pragmatic language development. During a 4-year longitudinal study of three children with CIs, certain aspects of pragmatic language development were observed in free…

  19. Study of the wavefront aberrations in children with amblyopia

    Institute of Scientific and Technical Information of China (English)

    ZHAO Peng-fei; ZHOU Yue-hua; WANG Ning-li; ZHANG Jing

    2010-01-01

    Background Amblyopia is a common ophthalmological condition and the wavefront aberrometer is a relatively new diagnostic tool used globally to measure optical characteristics of human eyes as well as to study refractive errors in amblyopic eyes. We studied the wavefront aberration of the amblyopic children's eyes and analyzed the mechanism of the wavefront aberration in the formation of the amblyopia, try to investigate the new evidence of the treatment of the amblyopia, especially in the refractory amblyopia.Methods The WaveScan Wavefront System (VISX, USA) aberrometer was used to investigate four groups of children under dark accommodation and cilliary muscle paralysis. There were 45 cases in the metropic group, 87 in the amblyopic group, 92 in the corrected-amblyopic group and 38 in the refractory amblyopic group. One-way analysis of variance (ANOVA), t-test and multivariate linear regression were used to analyze all the data.Results Third order to 6th order aberrations showed a decreasing trend whereas in the higher order aberrations the main ones were 3rd order coma (Z3-1-Z31), trefoil (Z3-3-Z33) and 4th order aberration (Z40); and 3rd order coma represented the highest percentage of all three main aberrations. Within 3rd order coma, vertical coma (Z3-1) accounted for a greater percentage than horizontal coma (Z31). Significant differences of vertical coma were found among all clinical groups of children: vertical coma in the amblyopic group (0.17±0.15) was significantly higher than in the metropic group (0.11±0.13, P0.05).Conclusions Although lower order aberrations such as defocus (myopia and hyperopia) and astigmatism are major factors determining the quality of the retinal image, higher order aberrations also need to be considered in amblyopic eyes as their effects are significant.

  20. A STUDY INTO DETERMINING THE MATHEMATICAL DEVELOPMENT OF CHILDREN ATTENDING TO A KINDERGARTEN

    OpenAIRE

    ÇELİK, Meryem

    2014-01-01

    The current study was carried out to determine the mathematical development levels of children attending to a preschool education institution in terms of mathematical content. The research was conducted on 334 children between 60-72 months attending to an independent kindergarten. The mathematical development level of children was measured through Progress in Math 6 Test. As a result of the statistics obtained, it was found that the success of the children for ?Shapes-Space-Measurements? and ...

  1. A prospective study of the causes of febrile illness requiring hospitalization in children in Cambodia.

    OpenAIRE

    Chheng, K; Carter, MJ; Emary, K; Chanpheaktra, N; Moore, CE; Stoesser, N.; Putchhat, H.; Sona, S; Reaksmey, S; Kitsutani, P; Sar, B.; van Doorn, HR; Uyen, NH; Tan, L.; Paris, D.

    2013-01-01

    Febrile illnesses are pre-eminent contributors to morbidity and mortality among children in South-East Asia but the causes are poorly understood. We determined the causes of fever in children hospitalised in Siem Reap province, Cambodia. A one-year prospective study of febrile children admitted to Angkor Hospital for Children, Siem Reap. Demographic, clinical, laboratory and outcome data were comprehensively analysed. Between October 12(th) 2009 and October 12(th) 2010 there were 1225 e...

  2. Changes in autistic trait indicators in parents and their children with ASD: A preliminary longitudinal study.

    Science.gov (United States)

    Hasegawa, Chiaki; Kikuchi, Mitsuru; Yoshimura, Yuko; Hiraishi, Hirotoshi; Munesue, Toshio; Takesaki, Natsumi; Higashida, Haruhiro; Oi, Manabu; Minabe, Yoshio; Asada, Minoru

    2015-08-30

    This study investigated whether the longitudinal changes in symptom severity in children with autism spectrum disorder (ASD) are associated with changes in the parents׳ autistic traits. The results demonstrated two significant correlations between the changes in children׳s Social Responsiveness Scale (SRS) scores and the Social Responsiveness Scale (SRS) score changes in either the father or both parents. Autistic symptom mitigation in ASD children was associated with increased empathy levels in their parents. PMID:26099658

  3. A qualitative study of the factors that influence mothers when choosing drinks for their young children

    OpenAIRE

    Hoare, Alexandria; Virgo-Milton, Monica; Boak, Rachel; Gold, Lisa; Waters, Elizabeth; Gussy, Mark; Calache, Hanny; Smith, Michael; de Silva, Andrea M.

    2014-01-01

    Background The consumption of sweetened beverages is a known common risk factor for the development of obesity and dental caries in children and children consume sweet drinks frequently and in large volumes from an early age. The aim of this study was to examine factors that influence mothers when choosing drinks for their children. Method Semi-structured interviews (n = 32) were conducted with a purposive sample of mothers of young children from Victoria’s Barwon South Western Region (select...

  4. Low Motor Assessment: A Comparative Pilot Study with Young Children With and Without Motor Impairment

    OpenAIRE

    Ruiter, Selma Anne José; Nakken, Han; van der Meulen, Bieuwe F.; Lunenborg, Carolien B.

    2009-01-01

    Most of the developmental instruments that measure cognitive development in children rely heavily on fine motor skills, especially for young children whose language skills are not yet well developed. This is problematic when evaluating the cognitive development of young children with motor impairment. The purpose of this study is to assess the need for a Low Motor adapation of a standardized instrument when testing children with motor impairment. To accomplish this, we have adapted the proced...

  5. Children and their parents: A comparative study of the legal position of children with regard to their intentional and biological parents in English and Dutch law

    OpenAIRE

    Vonk, M.J.

    2007-01-01

    This is a book about children and their parents. There are many different kinds of children and at least about as many different kinds of parents. In addition to the many different disciplines that study children and their parents, such as sociology, psychology, child studies and gender studies, to name but a few, this study concerns a legal question with regard to the parent-child relationship, namely how the law assigns parents to children. This subject is approached in a comparative legal ...

  6. Charge density waves in 1T-TaS2: an angle-resolved photoemission study

    Energy Technology Data Exchange (ETDEWEB)

    Clerc, F. [Institut de Physique, Universite de Neuchatel, Rue A.L. Breguet 1, CH-2000 Neuchatel (Switzerland); Bovet, M. [Institut de Physique, Universite de Neuchatel, Rue A.L. Breguet 1, CH-2000 Neuchatel (Switzerland); Berger, H. [Institut de Physique Appliquee, EPFL, CH-1015 Lausanne (Switzerland); Despont, L. [Institut de Physique, Universite de Neuchatel, Rue A.L. Breguet 1, CH-2000 Neuchatel (Switzerland); Koitzsch, C. [Institut de Physique, Universite de Neuchatel, Rue A.L. Breguet 1, CH-2000 Neuchatel (Switzerland); Garnier, M.G. [Institut de Physique, Universite de Neuchatel, Rue A.L. Breguet 1, CH-2000 Neuchatel (Switzerland); Aebi, P. [Institut de Physique, Universite de Neuchatel, Rue A.L. Breguet 1, CH-2000 Neuchatel (Switzerland)]. E-mail: philipp.aebi@unine.ch

    2004-09-15

    The transition metal dichalcogenide 1T-TaS2 is a layered material exhibiting charge density waves. Based on angle-resolved photoemission experiments mapping spectral weight at the Fermi surface and density functional theory calculations we discuss possible mechanisms involved with the creation of charge density waves. At first the flat parts of the elliptically shaped Fermi surface appear to play an important role via Fermi surface nesting. A closer analysis of the charge density wave induced new Brillouin zones and the possible energy balance between elastic deformation energy and electronic energy points to a more complicated scenario.

  7. Charge density waves in 1T-TaS2: an angle-resolved photoemission study

    International Nuclear Information System (INIS)

    The transition metal dichalcogenide 1T-TaS2 is a layered material exhibiting charge density waves. Based on angle-resolved photoemission experiments mapping spectral weight at the Fermi surface and density functional theory calculations we discuss possible mechanisms involved with the creation of charge density waves. At first the flat parts of the elliptically shaped Fermi surface appear to play an important role via Fermi surface nesting. A closer analysis of the charge density wave induced new Brillouin zones and the possible energy balance between elastic deformation energy and electronic energy points to a more complicated scenario

  8. [A study of the necessity of cooling of charge-coupled devices in x-ray imaging systems].

    Science.gov (United States)

    Morgun, O N; Nemchenko, K E; Rogov, Iu V

    2006-01-01

    The goal of this work was to study one of the widely used X-ray imaging systems: luminescent screen-optical system-matrix of photosensitive charge-coupled device (CCD)-amplifier-analog-to-digital converter. Experimental and theoretical studies were performed to substantiate the necessity of cooling of charge-coupled devices for improvement of X-ray image characteristics. The obtained results reveal the necessity of cooling of CCD-matrix crystals in the X-ray imaging system under consideration. PMID:16610280

  9. Implications of surface charge and curvature for the binding orientation of Thermomyces lanuginosus lipase on negatively charged or zwitterionic phospholipid vesicles as studied by ESR spectroscopy

    DEFF Research Database (Denmark)

    Hedin, E.M.K.; Høyrup, Lise Pernille Kristine; Patkar, S.A.;

    2005-01-01

    , Y., et al. (2000) Biochemistry 39, 413-423]. The productive-mode binding orientation of TLL at the lipid-water interface of small unilamellar vesicles (SUV) consisting of 1-palmitoyl-2-oleoyi-sn-glycero-3-phosphati-dylglycerol (POPG) was previously determined using electron spin resonance (ESR......) spectroscopy in combination with site-directed spin-labeling [Hedin, E. M. K., et al. (2002) Biochemistry 41, 1418514196]. In our investigation, we have studied the interfacial orientation of TLL when bound to large unilamellar vesicles (LUV) consisting of POPG, and bound to SUV consisting of 1-palmitoyl-2...... fluorescence quenching efficiency between each spin-label positioned on TLL, and the lipid membrane. ESR exposure and fluorescence quenching data show that TILL associates closer to the negatively charged PG surface than the zwitterionic PC surface, and binds to both POPG LUV and POPC SUV predominantly through...

  10. Feasibility study of a lens-coupled charge-coupled device gamma camera

    International Nuclear Information System (INIS)

    A charge-coupled device (CCD) is generally used in a digital camera as a light-collecting device such as a photomultiplier tube (PMT). Because of its low sensitivity and very high dark current, CCD have not been popularly used for gamma imaging systems. However, a recent CCD technological breakthrough has improved CCD sensitivity, and the use of a Peltier cooling system can significantly minimize the dark current. In this study, we investigated the feasibility of a prototype CCD gamma camera consisting of a CsI scintillator, optical lenses, and a CCD module. Despite electron-multiplying (EM) CCDs having higher performance, in this study, we built a cost-effective system consisted of low-cost components compared to EMCCDs. Our prototype detector consists of a CsI scintillator, two optical lenses, and a conventional Peltier-cooled CCD. The performance of this detector was evaluated by acquiring the sensitivity, resolution, and the modulation transfer function (MTF). The sensitivity of the prototype detector showed excellent linearity. With a 1 mm-diameter pinhole collimator, the full width at half-maximum (FWHM) of a 1.1 mm Tc-99m line source image was 2.85 mm. These results show that the developed prototype camera is feasible for small animal gamma imaging.

  11. The uses of electron beam ion traps in the study of highly charged ions

    Energy Technology Data Exchange (ETDEWEB)

    Knapp, D.

    1994-11-02

    The Electron Beam Ion Trap (EBIT) is a relatively new tool for the study of highly charged ions. Its development has led to a variety of new experimental opportunities; measurements have been performed with EBITs using techniques impossible with conventional ion sources or storage rings. In this paper, I will highlight the various experimental techniques we have developed and the results we have obtained using the EBIT and higher-energy Super-EBIT built at the Lawrence Livermore National Laboratory. The EBIT employs a high-current-density electron beam to trap, ionize, and excite a population of ions. The ions can be studied in situ or extracted from the trap for external experiments. The trapped ions form an ionization-state equilibrium determined by the relative ionization and recombination rates. Ions of several different elements may simultaneously be present in the trap. The ions are nearly at rest, and, for most systems, all in their ground-state configurations. The electron-ion interaction energy has a narrow distribution and can be varied over a wide range. We have used the EBIT devices for the measurement of electron-ion interactions, ion structure, ion-surface interactions, and the behavior of low-density plasmas.

  12. Study of fluorescence characteristics of the charge-transfer reaction of quinolone agents with bromanil

    Science.gov (United States)

    Li, Wen-Ying; Chen, Xiao-Fang; Xuan, Chun-Sheng

    2009-01-01

    A spectrofluorimetric method was discussed for the determination of three antibacterial quinolone derivatives, ofloxacin (OFL), norfloxacin (NOR) and ciprofloxacin (CIP) through charge-transfer complexation (CTC) with 2,3,5,6-tetrabromo-1,4-benzoquinone (bromanil, TBBQ). The method was based on the reaction of these drugs as n-electron donors with the π-acceptor TBBQ. TBBQ was found to react with these drugs to produce a kind of yellow complexes and the fluorescence intensities of the complexes were enhanced by 29-36 times more than those of the corresponding monomers. UV-vis, 1H NMR and XPS techniques were used to study the complexes formed. The various experimental parameters affecting the fluorescence intensity were studied and optimized. Under optimal reaction conditions, the rectilinear calibration graphs were obtained in the concentration range of 0.021-2.42 μg mL -1, 0.017-2.63 μg mL -1 and 0.019-2.14 μg mL -1 for OFL, NOR and CIP, respectively. The methods developed were applied successfully to the determination of the subject drugs in their pharmaceutical dosage forms with good precision and accuracy compared to official and reported methods as revealed by t- and F-tests.

  13. Histopathological study of congenital aortic valve malformations in 32 children

    Institute of Scientific and Technical Information of China (English)

    HUANG Ping; WANG Hongwei; LI Yanping; CHENG Peixuan; LIU Qingjun; ZHANG Zhenlu; LIU Jianying

    2007-01-01

    The histopathological characteristics of congenital aortic valve malformations in children were investigated.All the native surgically excised aortic valves from 32 pediatric patients suffering from symptomatic aortic valve dysfunction due to congenital aortic valve malformations between January 2003 and December 2005 were studied macroscopically and microscopically.The patients' medical records were reviewed and the clinical information was extracted.The diagnosis was made by the clinical presentation,preoperative echocardiography,intraoperative examination,and postoperative histopathological study,excluding rheumatic ot degenerative aortic valve diseases,infective endocarditis and primary connective tissue disorders,e.g.Marfan syndrome.Among 32 children with congenital aortic valve malformations,the age was ranged from six to 18 years,with a mean of 14.9 years,and there were 27 boys and five girls (male:female = 5.4:1).There were five cases of aortic stenosis (AS,15.62%),25 cases of aortic insufficiency (AI,78.13 %)and two cases of AS-AI (6.25%),without other valve diseases.Twenty cases still had other congenital heart diseases:ventricular septal defect (19 cases),patent ductus arteriosus (two cases),double-chambered right ventricle (one case),aneurysm of the right anterior aortic sinus of valsalva (three cases).Histopathological examination indicated that the cusps became thickening with unequal size,irregular shape (coiling and prolapse edge),enhanced hardness,and partly calcification.Microscopic investigation revealed the unsharp structure of valve tissue,fibrosis,myxomatous,reduced collagen fiber,rupture of elastic fibers,different degrees of infiltration of inflammatory cells,secondary calcareous and lipid deposit,and secondary fibrosis.Congenital aortic valve malformations in children involve males more than females,mostly associated with other congenital heart diseases.Aortic insufficiency is more common in children with congenital aortic valve

  14. Orbital dependent ultrafast charge transfer dynamics of ferrocenyl-functionalized SAMs on gold studied by core-hole clock spectroscopy

    International Nuclear Information System (INIS)

    Understanding the charge transport properties in general of different molecular components in a self-assembled monolayer (SAM) is of importance for the rational design of SAM molecular structures for molecular electronics. In this study, we study an important aspect of the charge transport properties, i.e. the charge transfer (CT) dynamics between the active molecular component (in this case, the ferrocenyl moieties of a ferrocenyl-n-alkanethiol SAM) and the electrode using synchrotron-based core-hole clock (CHC) spectroscopy. The characteristic CT times are found to depend strongly on the character of the ferrocenyl-derived molecular orbitals (MOs) which mediate the CT process. Furthermore, by systemically shifting the position of the ferrocenyl moiety in the SAM, it is found that the CT characteristics of the ferrocenyl MOs display distinct dependence on its distance to the electrode. These results demonstrate experimentally that the efficiency and rate of charge transport through the molecular backbone can be modulated by resonant injection of charge carriers into specific MOs. (paper)

  15. Studies of the charge instabilities in the complex nano-objects: clusters and bio-molecular systems

    International Nuclear Information System (INIS)

    For the last 6 years, my main research works focused on i) the Coulomb instabilities and the fragmentation processes of fullerenes and clusters of fullerenes ii) the stability and the reactivity of complex bio-molecular systems. Concerning the clusters of fullerenes, which are van der Waals type clusters, we have shown that the multiply charged species, obtained in collisions with slow highly charged ions, keep their structural properties but become very good electric conductor. In another hand, with the aim to understand the role of the biologic environment at the molecular scale in the irradiation damage of complex biomolecules, we have studied the charge stabilities of clusters of small biomolecules and the dissociation processes of larger nano-hydrated biomolecules. Theses studies have shown that first, specific molecular recognition mechanisms continue to exist in gas phase and secondly, a small and very simple biochemical environment is enough to change the dynamics of instabilities. (author)

  16. Detailed study of the column-based priority logic readout of Topmetal-II- CMOS pixel direct charge sensor

    CERN Document Server

    An, Mangmang; Gao, Chaosong; Han, Mikyung; Huang, Guangming; Ji, Rong; Li, Xiaoting; Mei, Yuan; Pei, Hua; Sun, Quan; Sun, Xiangming; Wang, Kai; Xiao, Le; Yang, Ping; Zhang, Wei; Zhou, Wei

    2016-01-01

    We present the detailed study of the digital readout of Topmetal-II- CMOS pixel direct charge sensor. Topmetal-II- is an integrated sensor with an array of 72X72 pixels each capable of directly collecting external charge through exposed metal electrodes in the topmost metal layer. In addition to the time-shared multiplexing readout of the analog output from Charge Sensitive Amplifiers in each pixel, hits are also generated through comparators with individually DAC settable thresholds in each pixel. The hits are read out via a column-based priority logic structure, retaining both hit location and time information. The in-array column-based priority logic is fully combinational hence there is no clock distributed in the pixel array. Sequential logic and clock are placed on the peripheral of the array. We studied the detailed working behavior and performance of this readout, and demonstrated its potential in imaging applications.

  17. Case-Control Study of acute diarrhea in Children

    Directory of Open Access Journals (Sweden)

    A Vafaee

    2011-06-01

    Full Text Available

    Background: To determine the risk factor for acute diarrhea disease in children. Methods: In the survey, 220 cases and 220 controls were involved. Cases were children with loose watery feces, pathologically diagnosed as acute diarrhea by the physician, and enrolled from the Emergency Ward as the Incident Cases in Dr. Sheykh Hospital, Mashhad, northeast of Iran. Control group too, was enrolled from the same cases and the members were children whose risk factors disease were not the risk factor for acute diarrhea, and were enrolled from emergency ward of burn patients, accidents, acute respiratory diseases and eligible patients.

    Results: By using univariate logistic regression models, variables consisting used milk up to 6 months age, antibiotic usage during the last 15 days, mother's employment, mother's acquaintance with ORS, occupancy, and water slack during the week before illness, were significantly related with acute diarrhea. In a multiple logistic regression, the relationship between the said factors as the independent variables and acute diarrhea was studied. Use of formulas before 6 month age with (95% CI 1.77- 5.79 OR=3.21, and tenantry with (95% CI 1.24-2.71 OR=1.83, and mother

  18. Studies of charge neutral FCC Lattice Gas with Yukawa Interaction and Accelerated Cartesian Expansion method

    Science.gov (United States)

    Huang, He

    In this thesis, I present the results of studies of the structural properties and phase transition of a charge neutral FCC Lattice Gas with Yukawa Interaction and discuss a novel fast calculation algorithm---Accelerated Cartesian Expansion (ACE) method. In the first part of my thesis, I discuss the results of Monte Carlo simulations carried out to understand the finite temperature (phase transition) properties and the ground state structure of a Yukawa Lattice Gas (YLG) model. In this model the ions interact via the potential q iqjexp(-kappar> ij)/rij where qi,j are the charges of the ions located at the lattice sites i and j with position vectors R i and Rj; rij = Ri-Rj, kappa is a measure of the range of the interaction and is called the screening parameter. This model approximates an interesting quaternary system of great current thermoelectric interest called LAST-m, AgSbPbmTem+2. I have also developed rapid calculation methods for the potential energy calculation in a lattice gas system with periodic boundary condition bases on the Ewald summation method and coded the algorithm to compute the energies in MC simulation. Some of the interesting results of the MC simulations are: (i) how the nature and strength of the phase transition depend on the range of interaction (Yukawa screening parameter kappa) (ii) what is the degeneracy of the ground state for different values of the concentration of charges, and (iii) what is the nature of two-stage disordering transition seen for certain values of x. In addition, based on the analysis of the surface energy of different nano-clusters formed near the transition temperature, the solidification process and the rate of production of these nano-clusters have been studied. In the second part of my thesis, we have developed two methods for rapidly computing potentials of the form R-nu. Both these methods are founded on addition theorems based on Taylor expansions. Taylor's series has a couple of inherent advantages: (i) it

  19. Mirror therapy in children with hemiplegia: a pilot study.

    Science.gov (United States)

    Gygax, Marine Jequier; Schneider, Patrick; Newman, Christopher John

    2011-05-01

    Mirror therapy, which provides the visual illusion of a functional paretic limb by using the mirror reflection of the non-paretic arm, is used in the rehabilitation of hemiparesis after stroke in adults. We tested the effectiveness and feasibility of mirror therapy in children with hemiplegia by performing a pilot crossover study in ten participants (aged 6-14 y; five males, five females; Manual Ability Classification System levels: one at level I, two at level II, four at level III, three at level IV) randomly assigned to 15 minutes of daily bimanual training with and without a mirror for 3 weeks. Assessments of maximal grasp and pinch strengths, and upper limb function measured by the Shriner's Hospital Upper Extremity Evaluation were performed at weeks 0 (baseline), 3, 6 (intervention), and 9 (wash-out). Testing of grasp strength behind the mirror improved performance by 15% (p=0.004). Training with the mirror significantly improved grasp strength (with mirror +20.4%, p=0.033; without +5.9%, p>0.1) and upper limb dynamic position (with mirror +4.6%, p=0.044; without +1.2%, p>0.1), while training without a mirror significantly improved pinch strength (with mirror +6.9%, p>0.1; without +21.9%, p=0.026). This preliminary study demonstrates the feasibility of mirror therapy in children with hemiplegia and that it may improve strength and dynamic function of the paretic arm. PMID:21410693

  20. The study comparing parenting style of children with ADHD and normal children

    OpenAIRE

    Moghaddam, Mahboobeh Firouzkouhi; Assareh,Marzeyeh; Heidaripoor, Amirahossein; Rad,Raheleh Eslami; Pishjoo, Masoud

    2013-01-01

    Aim. Attention deficit-hyperactivity disorder is one of the most often diagnosed psychiatric disorders in children and adolescents based on hyperactivity, attention deficit and impulsivity criteria. This disorder causes a lot of problems at home, school and social situations. Considering the family and parenting factors in growth and development of ADHD children, the parenting interventions are consider as a primary intervention programs for this children. Parenting management training, based...

  1. Children of the atomic bomb survivors: A genetic study

    International Nuclear Information System (INIS)

    This volume represents the results of over 40 years of study of the latent health effects on the survivors of the atomic bomb blasts. Planning for this research began in 1946 and data collection has been ongoing since 1948. The work represents the efforts of both US and Japanese agencies and presents 13 papers which the editors believe represent the best scientific information related to the genetic effects of radiation exposure. In general, the results presented here indicate that radiation exposure effects on reproductive cells are less than previously thought. The paper contained here examine that question in light of effects on pregnancy outcome, sex ratio, congenital defects, and early mortality of children. The papers also present helpful comparison of these results with the results seen in experimental radiation studies with animals. For anyone interested in the risks associated with radiation studies, this book represents a vital collection of information

  2. Study of micro-dosimeter P-N junctions using ion beam induced charge

    International Nuclear Information System (INIS)

    Reversed bias p-n junction offered an excellent opportunity to understand the radiobiological effects of Boron Neutron Capture Therapy (BNCT) in tissues and carcinoma cells. Ionizing radiation creates electron hole pairs in semiconducting materials. Under an electric field the charge carriers can be tapped externally to produce charge pulses. Therefore the junction can serve as a micro-dosimeter for the detection of charged particles such as lithium and helium ions produced as a by-product of neutron capture by the boron and nitrogen nuclei respectively. By arranging the reverse biased p-n junctions into a two dimensional array, it offers the possibility of measuring the energy deposition pattern. In this paper, we have used the Ion Beam Induced Charge (IBIC) with a scanned MeV ion microbeam to image and characterise the array of p-n junctions (authors)

  3. A SYSTEMATIC STUDY ON THE SURFACE CHARGE OF MICROORGANISMS IN DRINKING WATER

    Science.gov (United States)

    The removal of microbiological pathogens from drinking water is an important function of water treatment. The mechanisms of particle and pathogen removal during coagulation/flocculation/filtration processes are well known. Surface charge is particularly important in particle dest...

  4. Successful recruitment strategies for prevention programs targeting children of parents with mental health challenges: An international study

    NARCIS (Netherlands)

    Doesum, K.T.M. van; Riebschleger, J.; Carroll, J.; Grové , C.; Lauritzen, C.; Mordoch, E.; Skerfving, A.

    2016-01-01

    Research substantiates children of parents with mental disorders including substance abuse face increased risk for emotional and behavioral problems. Although evidence suggests that support programs for children enhance resiliency, recruiting children to these groups remains problematic. This study

  5. Protecting children from the consequences of divorce: A longitudinal study of the effects of parenting on children's coping processes

    OpenAIRE

    Vélez, Clorinda E.; Wolchik, Sharlene A.; Tein, Jenn-Yun; Sandler, Irwin

    2011-01-01

    This study examined whether intervention-induced changes in mother-child relationship quality and discipline led to short-term (6 months) and long-term (6 years) changes in children's coping processes in a sample of 240 youth aged 9-12 years when assessed initially. Data were from a randomized, experimental trial of a parenting-focused preventive intervention designed to improve children's post-divorce adjustment. Three-wave prospective mediational analyses revealed that intervention-induced ...

  6. Perception of Other People's Attention Direction in Typically Developing Children and Children With Autism : An Eye-Tracking Study

    OpenAIRE

    2012-01-01

    An important social skill is to monitor other people’s gaze to find out what catches their attention. Direct gaze alternated with raised eyebrows is an ostensive cue that make typically developing infants more interested in looking at the object attended to by another person. In the current study, we focused on the sensitivity to such cues in two groups of typically developing (TD) children (infants and preschoolers) as well as preschool children with an autism spectrum disorder (ASD). It is ...

  7. Study of some biochemical and genetic markers in asthmatic children

    International Nuclear Information System (INIS)

    Bronchial asthma is the most common chronic disease of childhood. Interleukin-4 (IL-4) and interleukin-13 (IL-13) are T-helper type 2 (Th2) cytokines with numerous activities that contribute to allergic inflammation and asthma. Both IL-4 and IL-13 use the IL-4 receptor alpha chain (IL-4 Ra) as a component of their respective systems. Allelic variants of IL-4 Ra have been reported and the R 576 IL-4 Ra allele was recently shown to be a risk factor for atopy. This study was designed to determine whether the R 576 allele was associated with the prevalence of asthma among children and also to evaluate the role of serum IL-4 and IL-13 in the development of asthma. Hence, we used a developed, rapid and reliable PCR-based assay to screen individuals for the R 576 IL-4 Ra allele. This assay has also used to genotype prospectively both recruited children with asthma (n = 22) and controls (n = 11). Serum IL-4 and IL-13 were determined by ELISA. The results of the PCR-based assay revealed a significant association of R 576 IL-4 Ra with the prevalence of all asthmatics, Chi-square (x2) 4.035; P 2 = 4.197, P 2 = 0.609, P > 0.05). Consequently, R 576 IL-4 Ra acts as an allergic asthma susceptibility gene. Also, asthmatic children displayed higher significant levels of IL-4 and IL-13 (P <0.()1). Allergic group exhibited significant higher levels of IL-4 (P < 0.001) and IL-13 (P < 0. 05). This gave clear evidence that both cytokines contributed to the development of asthma especially the allergic phenotype

  8. STUDY OF STATIC ELECTRICITY CHARGE ACCUMULATION ON SURFACE OF FLUOROPOLYMER-4 PRODUCTS USING VIBRATING CAPACITOR METHOD

    Directory of Open Access Journals (Sweden)

    H. Vershina

    2014-10-01

    Full Text Available The paper presents investigations of processes pertaining to surface charge accumulation and running of fluoropolymer-4 products using vibrating capacitor method. Modification of a measurement technique allowing to register distribution of dielectric surface potential without disturbance of the surface charged state has been described in the paper. The paper contains graphics of spatial distribution of surface potential of fluoropolymer-4 products after various treatments. The paper reveals that thermal treatment (tempering reduces static characteristics of fluoropolymer-4.

  9. Charge Transfer and Bonding Strength in Lithium-intercalated Polyaromatic Hydrocarbons Studied by Photoelectron Spectroscopy

    Institute of Scientific and Technical Information of China (English)

    R.Friedlein

    2007-01-01

    1 Results The potential applications of small-, medium-and large-size polyaromatic hydrocarbons for charge and energy storage in lithium metal and lithium ion batteries are discussed. In order to find the best carbon-based electrode materials, the specific roles of the molecular and solid-state contributions have to be understood. For the molecular contributions, a semi-quantitative method is proposed to compare the charge storage capability of polyaromatic hydrocarbon molecules. A compilation of result...

  10. Solution, surface, and single molecule platforms for the study of DNA-mediated charge transport

    OpenAIRE

    Muren, Natalie B.; Olmon, Eric D.; Barton, Jacqueline K.

    2012-01-01

    The structural core of DNA, a continuous stack of aromatic heterocycles, the base pairs, which extends down the helical axis, gives rise to the fascinating electronic properties of this molecule that is so critical for life. Our laboratory and others have developed diverse experimental platforms to investigate the capacity of DNA to conduct charge, termed DNA-mediated charge transport (DNA CT). Here, we present an overview of DNA CT experiments in solution, on surfaces, and with single molecu...

  11. Scanning capacitance microscope study of a SiO2/Si interface modified by charge injection

    Science.gov (United States)

    Tomiye, H.; Yao, T.

    We have investigated the local electrical properties of an SiO2/Si structure using a scanning capacitance microscope (SCaM) combined with an atomic force and a scanning tunneling microscope (AFM and STM). The electrical properties of the Si substrate and the SiO2/Si interface vary with position. In this experiment we have injected charge into the SiO2 and investigated the nature of charge storage at the SiO2/Si interface. We have used the combined microscope to apply a pulse to the SiO2/Si sample, causing charge to be trapped in the SiO2/Si interface. We could clearly detect the local variation of interface charge in a non-destructive manner using the SCaM and simultaneously by capacitance-voltage (C-V) characterization. The volume of the C-V curve shift along the voltage axis due to trapped charges is dependent upon the density of the trapped charges. In doing this experiment we show one of the many possible applications of the combined SCaM/AFM/STM.

  12. Dynamic Charge Storage in Ionic Liquids-Filled Nanopores: Insight from a Computational Cyclic Voltammetry Study.

    Science.gov (United States)

    He, Yadong; Huang, Jingsong; Sumpter, Bobby G; Kornyshev, Alexei A; Qiao, Rui

    2015-01-01

    Understanding the dynamic charge storage in nanoporous electrodes with room-temperature ionic liquid electrolytes is essential for optimizing them to achieve supercapacitors with high energy and power densities. Herein, we report coarse-grained molecular dynamics simulations of the cyclic voltammetry of supercapacitors featuring subnanometer pores and model ionic liquids. We show that the cyclic charging and discharging of nanopores are governed by the interplay between the external field-driven ion transport and the sloshing dynamics of ions inside of the pore. The ion occupancy along the pore length depends strongly on the scan rate and varies cyclically during charging/discharging. Unlike that at equilibrium conditions or low scan rates, charge storage at high scan rates is dominated by counterions while the contribution by co-ions is marginal or negative. These observations help explain the perm-selective charge storage observed experimentally. We clarify the mechanisms underlying these dynamic phenomena and quantify their effects on the efficiency of the dynamic charge storage in nanopores. PMID:26263086

  13. Systematic study of individual charge-changing cross sections of intermediate-energy secondary beams

    International Nuclear Information System (INIS)

    Highlights: • Precision total and partial charge-changing cross section measurements of medium-mass nuclides were performed. • Systematic reaction data of intermediate-energy heavy-ion beams were obtained. • A significant odd-even effect is found in the partial charge-changing cross sections. -- Abstract: Charge-changing interactions of stable and unstable medium-mass nuclides have been systematically investigated at intermediate energies. Secondary beams ranging from Ar to Ge isotopes produced by projectile fragmentation of 56Fe and 70Ge were irradiated onto a carbon target, and their total and partial charge-changing cross sections were precisely measured. A clear odd–even effect found in the partial charge-changing cross sections monotonically varies as a function of the Z/N ratio among the isotopes, and grows toward the neutron-deficient side. The total charge-changing cross sections are sensitive to the Z number of nuclides, and tend to gradually increase toward the neutron-deficient side in some isotopes

  14. In-situ deformation study of porous nanocrystalline Pd during electrochemical charging

    Energy Technology Data Exchange (ETDEWEB)

    Raghavan Nadar, Viswanath; Kramer, Dominik [Forschungszentrum Karlsruhe, Institut fuer Nanotechnologie, Karlsruhe (Germany); Weissmueller, Joerg [Forschungszentrum Karlsruhe, Institut fuer Nanotechnologie, Karlsruhe (Germany); Technische Physik, Universitaet des Saarlandes, Saarbruecken (Germany)

    2008-07-01

    The length of porous nanocrystalline palladium in a nearly neutral aqueous NaF (0.7 M) electrolyte was measured using a commercial dilatometer as a function of the applied electrode potential and of the charge. As expected, the sample expands during formation of the palladium hydride phases. However, the length is not just a simple function of the faradaic charge, but shows a remarkable fine structure which we discuss using a comparison with other nanoporous samples, e.g. gold and platinum. Even without hydrogen ad- or absorption, the length of nanometals varies as a function of charge due to the variation of surface stress with charge density, which causes large variations of the bulk pressure of nanomaterials due to their large ratio of the number of surface atoms relative to the number of bulk atoms. The surface stress behaviour of palladium observed at potentials positive of the hydrogen adsorption is qualitatively similar to that of porous platinum, although there is a quantitative difference if one relates the expansion to the charge density, e.g. by calculating the surface stress-charge coefficient. The highly reproducible cyclic strain caused by hydrogen absorption and -desorption in Pd is larger than the surface stress effects by more than an order of magnitude.

  15. Complications of continuous renal replacement therapy in critically ill children: a prospective observational evaluation study

    OpenAIRE

    Santiago, Maria J; López-Herce, Jesús; Urbano, Javier; Solana, María José; del Castillo, Jimena; Ballestero, Yolanda; Botrán, Marta; Bellón, Jose María

    2009-01-01

    Introduction Continuous renal replacement therapy (CRRT) frequently gives rise to complications in critically ill children. However, no studies have analyzed these complications prospectively. The purpose of this study was to analyze the complications of CRRT in children and to study the associated risk factors. Methods A prospective, single-centre, observational study was performed in all critically ill children treated using CRRT in order to determine the incidence of complications related ...

  16. A comparison study of educational involvement of hearing parents of deaf and hearing children of elementary school age.

    Science.gov (United States)

    Powers, G W; Saskiewicz, J A

    1998-03-01

    This study was conducted to determine if a difference exists in level of educational involvement between hearing parents of deaf children and hearing parents of hearing children. Participating parents were asked to complete a 23-question survey about their involvement in their children's education over the past year. Neither group of parents demonstrated a significantly higher level of involvement in their children's education. However, parents of deaf children observed their children in the classroom more than parents of hearing children; parents of hearing children volunteered in their child's classroom more than parents of deaf children. PMID:9557331

  17. Charge Transport in Molecular Junctions: A Study of Level-Alignment, Thermoelectric Properties, and Environmental Effects

    Science.gov (United States)

    Kotiuga, Michele

    Here, we use and develop first-principles methods based on density functional theory (DFT) and beyond to understand and predict charge transport phenomena in the novel class of nanostructured devices: molecular junctions. Molecular junctions, individual molecules contacted to two metallic leads, which can be systematically altered by modifying the chemistry of each component, serve as test beds for the study of transport at the nanoscale. To date, various experimental methods have been designed to reliably assemble and measure transport properties of molecular junctions. Furthermore, theoretical methods built on DFT designed to yield quantitative agreement with these experiments for certain classes of molecular junctions have been developed. In order to gain insight into a broader range of molecular junctions and environmental effects associated with the surrounding solution, this dissertation will employ, explore and extend first-principles DFT calculations coupled with approximate self-energy corrections known to yield quantitative agreement with experiments for certain classes of molecular junctions. To start we examine molecular junctions in which the molecule is strongly hybridized with the leads: a challenging limit for the existing methodology. Using a physically motivated tight-binding model, we find that the experimental trends observed for such molecules can be explained by the presence of a so-called "gateway" state associated with the chemical bond that bridges the molecule and the lead. We discuss the ingredients of a self-energy corrected DFT based approach to quantitatively predict conductance in the presence of these hybridization effects. We also develop and apply an approach to account for the surrounding environment on the conductance, which has been predominantly ignored in past transport calculations due to computational complexity. Many experiments are performed in a solution of non-conducting molecules; far from benign, this solution is known

  18. Experimental study of the electric charge process of the radioactive aerosols beta emitter; Etude experimentale du processus de charge electrique des aerosols radioactifs emetteurs beta

    Energy Technology Data Exchange (ETDEWEB)

    Gensdarmes, F.; Boulaud, D. [CEA/Saclay, Inst. de Protection et de Surete Nucleaire, IPSN/DPEA/SERAC, 91 - Gif-sur-Yvette (France); Renoux, A. [Paris-12 Univ., Lab. de Physique des Aerosols et de Transfert des Contaminations, 94 - Creteil (France)

    2000-07-01

    An aerosol radioactivity may change its electrical properties and then modify its evolution in a closed room. In order to define the electric charge state of a radioactive aerosol, an experimental device has been developed to produce a calibrated radioactive aerosol of cesium 137. The results show an increase of the aerosol average charge when the particles specific activity increase. (A.L.B.)

  19. Environmentally Reformed Travel Habits During the 2006 Congestion Charge Trial in Stockholm—A Qualitative Study

    Directory of Open Access Journals (Sweden)

    Håkan Andréasson

    2011-08-01

    Full Text Available Policy measures that reduce or replace road traffic can improve environmental conditions in most large cities. In Stockholm a congestion charge was introduced during a test period in 2006. This was a full-scale trial that proved to meet its targets by reducing traffic crossing the inner city segment during rush hours by 20%. Emissions of carbon dioxide and particles were also substantially reduced. This study, based on in-depth interviews with 40 inhabitants, analyses how and why new travel habits emerged. The results show that particular, sometimes unexpected, features of everyday life (habits, resources, opportunities, values, etc. were crucial for adjustment of travel behaviour in relation to the policy instrument. One example was that those accustomed to mixing different modes of transport on a daily basis more easily adapted their travel in the targeted way. On a more general level, the results revealed that the policy measure could actually tip the scales for the individual towards trying out a new behaviour.

  20. First-principles studies on the charge density wave in uranium

    Science.gov (United States)

    Qiu, Ruizhi; Lu, Haiyan; Ao, Bingyun; Tang, Tao; Chen, Piheng

    2016-06-01

    The charge density wave (CDW) state of α-U (called {α1} -U) was studied through a first-principles total-energy minimization using the conjugate gradient algorithm. The optimized crystal structure of {α1} -U was found to have the space group Pbnm, which was proposed in the earlier Landau-type theory and is isostructural with the α-Np structure. In particular, the changes in the lattice parameters of Pbnm-U with respect to α-U are consistent with the experimental observations. In addition, the energetic stability of Pbnm-U with respect to α-U was confirmed by enthalpy calculations, and the value of the critical pressure in the pressure-induced quantum transition from Pbnm-U to α-U is in good agreement with the experimental result. Moreover, the phonon calculation verified the dynamical instability of α-U and the stability of Pbnm-U. Finally, the calculated electronic structures exhibit features of the CDW state.

  1. Environmentally reformed travel habits during the 2006 congestion charge trial in Stockholm--a qualitative study.

    Science.gov (United States)

    Henriksson, Greger; Hagman, Olle; Andréasson, Håkan

    2011-08-01

    Policy measures that reduce or replace road traffic can improve environmental conditions in most large cities. In Stockholm a congestion charge was introduced during a test period in 2006. This was a full-scale trial that proved to meet its targets by reducing traffic crossing the inner city segment during rush hours by 20%. Emissions of carbon dioxide and particles were also substantially reduced. This study, based on in-depth interviews with 40 inhabitants, analyses how and why new travel habits emerged. The results show that particular, sometimes unexpected, features of everyday life (habits, resources, opportunities, values, etc.) were crucial for adjustment of travel behaviour in relation to the policy instrument. One example was that those accustomed to mixing different modes of transport on a daily basis more easily adapted their travel in the targeted way. On a more general level, the results revealed that the policy measure could actually tip the scales for the individual towards trying out a new behaviour. PMID:21909301

  2. Colossal resistivity change associated with the charge ordered/disordered transition:Monte Carlo study

    Institute of Scientific and Technical Information of China (English)

    DONG Shuai; ZHU Han; LIU Jun-ming

    2006-01-01

    Earlier theoretical approaches to manganites mainly stern from magnetic framework in which the electronic transports are thought to be spin-dependent and the double exchange plays a vital role.However,quite a number of experimental observations cannot be explained in the magnetic framework,yet.For example,multiplicate insulator-metal transitions and resistivity reduction induced by perturbations other than magnetic field,such as electric current,are not well understood in this framework.Here we present a comprehensive analysis on the magnetic framework and give a Monte Carlo study on the resistivity of a charge ordered/disordered model without accounting for the spin degree of freedom.The result shows a colossal resistivity change as a resultant of the transition between two types of insulated states.This transition has intrinsic difference from the popular insulated-to-metallic transition in the magnetic framework.The present scenario can be used to explain some experimental facts for electronic transports in manganites,which are not accessible in the magnetic framework.

  3. Study of charge collection and noise in non-irradiated and irradiated silicon detectors

    Energy Technology Data Exchange (ETDEWEB)

    Leroy, C. [Montreal Univ., PQ (Canada); Bates, S. [CERN, ECP, CH-1211 Geneva (Switzerland); Dezillie, B. [CERN, ECP, CH-1211 Geneva (Switzerland); Glaser, M. [CERN, ECP, CH-1211 Geneva (Switzerland); Lemeilleur, F. [CERN, ECP, CH-1211 Geneva (Switzerland); Trigger, I. [Montreal Univ., PQ (Canada)

    1997-04-01

    Charge collection and noise were studied in non-irradiated and irradiated silicon detectors as a function of temperature (T), shaping time ({theta}) and fluence ({Phi}), up to about 1.2 x 10{sup 14} protons cm{sup -2}, for minimum ionizing electrons yielded by a {sup 106}Ru source. The noise of irradiated detectors is found dominated for short shaping times ({theta}{<=}50 ns) by a series noise component while for longer shaping time ({theta}{>=}80 ns) a parallel noise component (correlated with the reverse current) prevails. For non-irradiated detectors, where the reverse current is three orders of magnitude smaller compared with irradiated detectors, the series noise dominates over the whole range of shaping times investigated (20-150 ns). A signal degradation is observed for irradiated detectors. However, the signal can be distinguished from noise, even after a fluence of about 1.2 x 10{sup 14} protons cm{sup -2}, at a temperature of 6 C and with a shaping time typical of LHC inter-bunch crossing time (20-30 ns). The measurement of the signal as a function of voltage shows that irradiated detectors depleted at 50% of the full depletion voltage can still provide a measurable signal-to-noise ratio. (orig.).

  4. Unveiling the nucleon tensor charge at Jefferson Lab: A study of the SoLID case

    CERN Document Server

    Ye, Zhihong; Allada, Kalyan; Liu, Tianbo; Chen, Jian-Ping; Kang, Zhong-Bo; Prokudin, Alexei; Sun, Peng; Yuan, Feng

    2016-01-01

    Future experiments at the Jefferson Lab 12 GeV upgrade, in particular, the Solenoidal Large Intensity Device (SoLID), aim at a very precise data set in the region where the partonic structure of the nucleon is dominated by the valence quarks. One of the main goals is to constrain the quark transversity distributions. We apply recent theoretical advances of the global QCD extraction of the transversity distributions to study the impact of future experimental data from the SoLID experiments. Especially, we develop a simple strategy based on the Hessian matrix analysis that allows one to estimate the uncertainties of the transversity quark distributions and their tensor charges extracted from SoLID data simulation. We find that the SoLID measurements with the proton and the effective neutron targets can improve the precision of the u- and d-quark transversity distributions up to one order of magnitude in the range 0.05 < x < 0.6.

  5. Microscopic theoretical study of Raman spectra in charge and spin ordered cuprate systems

    Energy Technology Data Exchange (ETDEWEB)

    Raj, B.K. [Dept. of Physics, Govt. Autonomous College, Angul, Orissa (India); Panda, S.K. [KD Science College, Pochilima, Hinjilicut, 761 101 Ganjam, Orissa (India); Rout, G.C., E-mail: gcr@iopb.res.in [Condensed Matter Physics Group, PG Dept. of Applied Physics and Ballistics, FM University, Balasore 756 019 (India)

    2013-09-15

    Highlights: • The model calculation treats CDW interaction as pseudogap for cuprates. • The interplay of Raman active CDW-SDW mixed modes are investigated. • Independent CDW and SDW gap values can be determined from experimental data. -- Abstract: Raman scattering is one of the most powerful methods to investigate the electron as well as the phonon excitations in the systems. In this communication, we present a theoretical study of Raman scattering in the normal state of the high-T{sub C} systems in the under-doped region displaying the interplay of the spin-density-wave (SDW) and charge-density-wave (CDW) interactions. The SDW order arises from the repulsive Coulomb interaction of electrons, while the CDW order arises due to strong electron–phonon interaction giving rise to Fermi surface instability. We calculate phonon response function in order to examine the possibility of observing the SDW excitation mode in presence of the CDW interaction present in the same conduction band. The Raman scattering intensity is calculated from the imaginary part of the phonon Green’s function assigning an arbitrary spectral width. The spectral density function displays two mixed modes of excitation peaks at energies 2(Δ{sub c} ± Δ{sub s}). The evolution of excitation peaks are investigated by varying CDW coupling, SDW coupling and the phonon momentum transfer energy.

  6. Numerical study of an electrostatic plasma sheath containing two species of charged dust particles

    Energy Technology Data Exchange (ETDEWEB)

    Foroutan, G. [Physics Department, Faculty of Science, Sahand University of Technology, 51335-1996 Tabriz (Iran, Islamic Republic of); Akhoundi, A. [Nanostructure Material Research Center, Sahand University of Technology, 51335-1996 Tabriz (Iran, Islamic Republic of)

    2012-10-01

    A multi-fluid model is used to study the dynamics of a dusty plasma sheath consists of electrons, ions, and two species of charged dust particles, i.e., nano-size and micron-size particles. It is found that, when the sheath is dominated by the nano-size dust grains, spatially periodic fluctuations are developed in the profiles of the sheath potential, and the number density and velocity of the plasma and dust particles. Due to inertial effects, the fluctuations in the parameters of the micron-size grains are much lower than those of the other parameters. The competition between the electric and ion drag forces plays the primary role in development of the fluctuations. The spatial period of the fluctuations is approximately a few Debye lengths and their amplitude depends on the plasma and dust parameters. The fluctuations are reduced by the increase in the radius, mass density, and Mach number of the nano-size particles, as well as the density and Mach number of the ions. But, they are enhanced by the increase in the plasma number density and the electron temperature. The sheath thickness demonstrates a non-monotonic behavior against variation of the nanoparticle parameters, i.e., it first decreases quickly, shows a minimum, and then increases. However, the sheath width always decreases with the plasma number density and ion Mach number, while grows linearly with the electron temperature.

  7. Numerical study of an electrostatic plasma sheath containing two species of charged dust particles

    International Nuclear Information System (INIS)

    A multi-fluid model is used to study the dynamics of a dusty plasma sheath consists of electrons, ions, and two species of charged dust particles, i.e., nano-size and micron-size particles. It is found that, when the sheath is dominated by the nano-size dust grains, spatially periodic fluctuations are developed in the profiles of the sheath potential, and the number density and velocity of the plasma and dust particles. Due to inertial effects, the fluctuations in the parameters of the micron-size grains are much lower than those of the other parameters. The competition between the electric and ion drag forces plays the primary role in development of the fluctuations. The spatial period of the fluctuations is approximately a few Debye lengths and their amplitude depends on the plasma and dust parameters. The fluctuations are reduced by the increase in the radius, mass density, and Mach number of the nano-size particles, as well as the density and Mach number of the ions. But, they are enhanced by the increase in the plasma number density and the electron temperature. The sheath thickness demonstrates a non-monotonic behavior against variation of the nanoparticle parameters, i.e., it first decreases quickly, shows a minimum, and then increases. However, the sheath width always decreases with the plasma number density and ion Mach number, while grows linearly with the electron temperature.

  8. 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 (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.

  9. Experimental studies on the weakly ferromagnetic metals and the quasi-one-dimensional organic charge transfer salts

    Science.gov (United States)

    Yu, Weiqiang

    Weakly magnetic metals and quasi-1D organic charge transfer salts are two examples of strongly correlated electron systems, and the phase transitions of both can be tuned by application of hydrostatic pressure. Here we examine several weakly ferromagnetic metals and quasi-ID organic charge transfer salts using high pressure NMR, transport, and susceptibility. The zero-field NMR of high-pressure MnSi reveals an inhomogeneous magnetic phase starting from an intermediate pressure P*, and local magnetism surviving far beyond the critical pressure PC. This phase inhomogeneity may lead to the non-Fermi liquid behavior in the high-pressure paramagnetic phase. However, the origin of phase inhomogeneity, whether due to slow fluctuations on the border of a first order phase transition, or due to spin-orbit coupling, is still unclear. Susceptibility studies on rhodium-doped MnSi demonstrate strong coupling between disorder and antiferromagnetic correlations by the formation of a spin glass state. The implications for the high pressure MnSi, where the fluctuations are expected to be more prominent, deserve further study. Our NMR and transport studies on the quasi-1D organic charge transfer salts (TMTCF)2X, indicate that charge ordering is stabilized through the combination of coupling to anionic motion, and long range intrastack Coulomb interactions. The charge ordering is found to suppress the spin-Peierls state and cooperate with antiferromagnetism. Based on this, we have established a new phase diagram for this class of materials. We looked for evidence of charge fluctuations in the metallic phase. Evidence for their existence is established by NMR spectroscopy. The nature of the low temperature conducting phase remains undetermined. Experiments give evidence for both Fermi liquid and non-Fermi liquid properties.

  10. Feasibility study: honey for treatment of cough in children

    Directory of Open Access Journals (Sweden)

    Naveed Ahmed

    2013-06-01

    Full Text Available Respiratory tract infections are an important health problem because of high incidence and economic costs. The World Health Organization identifies honey as a potential demulcent treatment for cough. The aim of this study is to determine: i patient public perceptions towards a proposed randomized controlled trial (RCT comparing the effects of honey to placebo for treatment of cough in children; ii potential participation rates for proposed trial; iii whether age and gender of parent or child impacts on proposed cough assessment tools. Forty adult participants with children age 1-6 years presenting with an upper respiratory tract infection were enrolled. They underwent a structured interview regarding the proposed trial and assessed their child’s cough using two validated questionnaires. Eighty-eight percent of those recruited were willing to participate in the proposed trial. The two independently validated cough scores correlated well. A relationship between age and gender of child or parent with cough assessment score was not found. We conclude that a RCT to determine the effects of honey versus placebo is feasible. The public find the outcome measures and trial design acceptable.

  11. Feasibility study: honey for treatment of cough in children.

    Science.gov (United States)

    Ahmed, Naveed; Sutcliffe, Alastair; Tipper, Claire

    2013-06-13

    Respiratory tract infections are an important health problem because of high incidence and economic costs. The World Health Organization identifies honey as a potential demulcent treatment for cough. The aim of this study is to determine: i) patient public perceptions towards a proposed randomized controlled trial (RCT) comparing the effects of honey to placebo for treatment of cough in children; ii) potential participation rates for proposed trial; iii) whether age and gender of parent or child impacts on proposed cough assessment tools. Forty adult participants with children age 1-6 years presenting with an upper respiratory tract infection were enrolled. They underwent a structured interview regarding the proposed trial and assessed their child's cough using two validated questionnaires. Eighty-eight percent of those recruited were willing to participate in the proposed trial. The two independently validated cough scores correlated well. A relationship between age and gender of child or parent with cough assessment score was not found. We conclude that a RCT to determine the effects of honey versus placebo is feasible. The public find the outcome measures and trial design acceptable. PMID:23904963

  12. Behavior modification with culturally deprived school children: two case studies.

    Science.gov (United States)

    Wasik, B H; Senn, K; Welch, R H; Cooper, B R

    1969-01-01

    Techniques of behavior modification were employed with two second-grade Negro girls in a demonstration school for culturally deprived children to increase the girls' appropriate classroom behaviors. A classification system that provided for continuous categorization of behavior was used to code the children's behavior in two classroom situations. Data were also taken on the type, duration, and frequency of the teachers' verbal interactions. The study included four conditions: Baseline, Modification I, Postmodification, and Modification II. The treatment variable was positive social reinforcement-attention and approval contingent upon desirable classroom behaviors-which was presented, withheld, or withdrawn (timeout from social reinforcement). Withholding of social reinforcement was contingent upon inappropriate attention-getting behaviors. Timeout from social reinforcement was contingent upon behaviors classified as aggressive and resistive. After 25 days of Modification I, desirable behavior increased markedly for each girl. The teachers were then asked to return to their Baseline level of performance. The resultant behaviors demonstrated that for one girl, behavior was still primarily under the control of the treatment contingencies. For the second child, many desirable behaviors that had increased in frequency during Modification I remained high, but inappropriate behaviors increased. When treatment was reinstated, the amount of time spent in desirable behaviors increased and remained high for both girls. Three checks during the three months following data collection showed that these behaviors continued to remain high. PMID:16795218

  13. Biochemical genetics study of children of atomic bomb survivors

    International Nuclear Information System (INIS)

    In order to investigate genetic effect of radiation, especially the rate of mutation, the presence of protein variants in plasma and blood cells of children (F1 generation) of A-bomb survivors was examined. Twenty four kinds of protein consisting of 6 serum proteins and 18 hemoglobin, sampled from 2,800 children have been studied to data by using starch gel electrophoresis. Variants were detected in 13 kinds of proteins in 91 samples and among which the variants were observed often in transferrin, phosphoglucomutase and phosphohexose isomerase. To know whether detected variant types were induced by mutation, 54 cases of parents were tested. Results indicated that same variant types were observed in either of their parents. From these findings, it was confirmed that the variation is genetic and was not related to A-bomb radiation to their parents. Though the incidence of variant types was different in Hiroshima and Nagasaki, The number of samples, is not big enough to conclude it to be regional difference. (Iwagami, H.)

  14. An experimental technique for the study of non-avalanche charge injection or trapping in MIS structures

    Science.gov (United States)

    Kolk, J.; Heasell, E.

    1980-03-01

    In the study of charge injection in the insulator-silicon system, variation of the electric field in the insulator, caused by charge trapping during a measurement, makes the interpretation and analysis of experimental data difficult. A measuring system and test device structure are described in which it is possible to monitor any change of the device threshold voltage and to adjust the applied gate voltage so as to maintain a constant electric field at the insulator-silicon interface. Experimental results will be presented which show the advantages stemming from this mode of operation.

  15. Study of the coherent propagation of charged leptons coming from pion and W decay in Bohmian mechanics

    Directory of Open Access Journals (Sweden)

    H Azizakram

    2015-12-01

    Full Text Available Although charged leptons, contrary to neutrinos, cannot oscillate, exploring whether a coherent  superposition of charged lepton states can change to others during the propagation is an important problem in the neutrino oscillation theory. In this paper, we consider electrons and muons coming from the pions and W decays and study their propagation in relativistic Bohmian quantum mechanics. We find out that the Bohmian trajectories of them are separated after atomic distance propagations. In fact, the computed Bohmian trajectories of electrons and muons coming from W and pion decays show that Bohmin results are consistent with those of standard quantum mechanics.

  16. Who Decides? Mothers' and Children's Beliefs about Food Choices

    OpenAIRE

    Rigney, Jennifer Carole

    2012-01-01

    What do mothers and children believe about whether parents are in charge of what and how much a child should eat? The current study explored children's beliefs about the scope of parental authority over food decisions and whether these beliefs depend on features of the situation. Additionally, relations between children's and their mothers' beliefs were explored. Mothers and their 5- or 7-year-old children were interviewed separately regarding 4 different types of hypothetical food-related d...

  17. Laser induced fluorescence studies of the charge transfer reactions of N2+ with Ar and N2

    International Nuclear Information System (INIS)

    The charge transfer reactions of N2+ with Ar and N2 have been studied using laser induced fluorescence to monitor N2+. The ions were formed initially within a quadrupole ion trap by electron impact of neutral N2. The experimental conditions were varied such that the trapped N2+ could be examined under collision free conditions or after experiencing a controlled number of collisions with selected background gas. The ion--molecule collisions rapidly altered the internal energy distribution of the trapped N2+ and by monitoring these changes charge transfer cross sections for individual initial vibrational states of the N2+ with Ar and N2 have been estimated. The results show a strong vibrational dependence of the charge transfer cross section in the N2+--N2 system and no measureable dependence in the N2+--Ar system

  18. Charge Transfer in FeO: A combined Molecular-Dynamics and Ab Initio Study

    International Nuclear Information System (INIS)

    Molecular dynamics simulations and ab initio electronic structure calculations were carried out to determine the rate of charge transfer in stoichiometric w-stite (FeO). The charge transfer of interest occurs by II/III valence interchange between nearest-neighbor Fe atoms, with the Fe(III) constituting a ''hole'' electronic defect. There are two possible nearest-neighbor charge transfers in the FeO lattice, which occur between edge-sharing or corner-sharing FeO6 octahedra. Molecular dynamics simulations predict charge transfer rates of 3.7x1011 and 1.9x109 s-1 for the edge and corner transfers, respectively, in good agreement with those calculated using an ab initio cluster approach (1.6x1011 and 8.0x108 s-1, respectively). The calculated rates are also similar to those along basal and c-axis directions in hematite (?-Fe2O3) determined previously. Therefore, as is the case for hematite, w-stite is predicted to show anisotropic electrical conductivity. Our findings indicate that a rigid ion model does not give acceptable results, thus showing the need to account for the change in polarizability of the system upon charge transfer. Our model achieves this by using a simple mechanical shell model. By calculating the electronic coupling matrix elements for many transition state configurations obtained from the molecular dynamics simulations, we found evidence that the position of the bridging oxygen atoms can greatly affect the amount electronic coupling between the donor and acceptor states. Finally, we address the effect of oxygen vacancies on the charge transfer. It was found that an oxygen vacancy not only creates a driving force for holes to transport away from the vacancy (or equivalently for electrons to diffuse toward the vacancy) but also lowers the free energy barriers for charge transfer. In addition, the reorganization energy significantly differed from the non-defective case in a small radius around the defect

  19. 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

  20. A study on the psychosocial behavior of the disabled children in Loni, Maharashtra

    OpenAIRE

    Rajagopal Rao Kodali; Sitarama P Charyulu

    2011-01-01

    Objectives:To find out the changes in psychosocial behavior of the disabled children. Materials and Methods: The study area comprises of villages under rural field practice area of Rural Medical College, Loni. 7300 children of the age group of 0-14 years from the total population of 20,533 were studied by community based cross- sectional study. House to house survey was conducted to identify disabled children using a pre-tested questionnaire by interview technique. Child behavior check list (...

  1. A Study of Pre-School Children's School Readiness Related to Scientific Thinking Skills

    OpenAIRE

    UNUTKAN, Ozgul Polat

    2006-01-01

    The purpose of this study is to compare school readiness of children who had pre-school experiences and children without such experiences on the basis of scientific thinking skills. This comparison is held in terms of variables of age, gender, and socio economic status. The questions of the study in relation to the purpose of the study are as follows: Ø Does pre-school education variable influence primary school readiness of pre-school children in terms of scientific thinking skills...

  2. Functional Stretching Exercise Submitted for Spastic Diplegic Children: A Randomized Control Study

    OpenAIRE

    Mohamed Ali Elshafey; Adel Abd-Elaziem; Rana Elmarzouki Gouda

    2014-01-01

    Objective. Studying the effect of the functional stretching exercise in diplegic children. Design. Children were randomly assigned into two matched groups. Setting. Outpatient Clinic of the Faculty of Physical Therapy, Cairo University. Participants. Thirty ambulant spastic diplegic children, ranging in age from five to eight years, participated in this study. Interventions. The control group received physical therapy program with traditional passive stretching exercises. The study group rece...

  3. Nutritional status and clinical outcome of children on continuous renal replacement therapy: a prospective observational study

    OpenAIRE

    Castillo Ana; Santiago Maria J; López-Herce Jesús; Montoro Sandra; López Jorge; Bustinza Amaya; Moral Ramón; Bellón Jose M

    2012-01-01

    Abstract Background No studies on continuous renal replacement therapy (CRRT) have analyzed nutritional status in children. The objective of this study was to assess the association between mortality and nutritional status of children receiving CRRT. Methods Prospective observational study to analyze the nutritional status of children receiving CRRT and its association with mortality. The variables recorded were age, weight, sex, diagnosis, albumin, creatinine, urea, uric acid, severity of il...

  4. Risk of metabolic syndrome among children living in metropolitan Kuala Lumpur: A case control study

    OpenAIRE

    Ismail Mohd N; Bulgiba Awang; Poh Bee K; Wee Bee S; Ruzita Abdul T; Hills Andrew P

    2011-01-01

    Abstract Background With the increasing prevalence of childhood obesity, the metabolic syndrome has been studied among children in many countries but not in Malaysia. Hence, this study aimed to compare metabolic risk factors between overweight/obese and normal weight children and to determine the influence of gender and ethnicity on the metabolic syndrome among school children aged 9-12 years in Kuala Lumpur and its metropolitan suburbs. Methods A case control study was conducted among 402 ch...

  5. Cognitive studies in children with mild mental retardation with externalizing behavioural disorders

    OpenAIRE

    Meer, Dirk Jan van der

    2000-01-01

    This study had an exploratory character. The aim was to gain more insight into the complex behaviour of children with mild mental retardation and externalizing behavioural disorders. This study is one of the first to focus on such a complex target-group. The goals were: making recommendations for future research, discovering tendencies central to behaviour and improving the treatment that such children receive. The children in this study are institutionalized and have a long history of care p...

  6. Impact on children of a parent with ALS: A case-control study

    OpenAIRE

    Vincenzo eCalvo; Francesca eBianco; Enrico eBenelli; Marco eSambin; Maria Rosaria eMonsurrò; Cinzia eFemiano; Giorgia eQuerin; Gianni eSorarù; Arianna ePalmieri

    2015-01-01

    Background: Numerous studies have explored how patients and their caregivers cope with amyotrophic lateral sclerosis (ALS), but the literature completely lacks research on the psychological impact of the disease on patients’ children. The aim of our study was to investigate the emotional and psychological impact of a parent with ALS on school-age children and adolescents in terms of problem behavior, adjustment, and personality characteristics.Methods: The study involved 23 children (mean age...

  7. Impact on children of a parent with ALS: a case-control study

    OpenAIRE

    Calvo, Vincenzo; Bianco, Francesca; Benelli, Enrico; Sambin, Marco; Monsurrò, Maria R.; Femiano, Cinzia; Querin, Giorgia; Sorarù, Gianni; Palmieri, Arianna

    2015-01-01

    Background: Numerous studies have explored how patients and their caregivers cope with amyotrophic lateral sclerosis (ALS), but the literature completely lacks research on the psychological impact of the disease on patients’ children. The aim of our study was to investigate the emotional and psychological impact of a parent with ALS on school-age children and adolescents in terms of problem behavior, adjustment, and personality characteristics. Methods: The study involved 23 children (mean...

  8. Children, parents and sports : An interview studie of upbringing as affected by soccer and golf

    OpenAIRE

    Karp, Staffan

    2000-01-01

    The purpose of this work is to describe and understand the significance of sports for children active in sports, their parents, and family. I am interested in how daily sports practice is understood by children active in sports and their parents and what sports mean for upbringing of children and young people. In the study eighteen children were interviewed, twelve boys and six girls in the ages of 10-12 years and their parents. Nine of the children play golf and nine play soccer. The perspec...

  9. Charge generation in organic solar cell materials studied by terahertz spectroscopy

    KAUST Repository

    Scarongella, M.

    2015-09-09

    We have investigated the photophysics in neat films of conjugated polymer PBDTTPD and its blend with PCBM using terahertz time-domain spectroscopy. This material has very high efficiency when used in organic solar cells. We were able to identify a THz signature for bound excitons in neat PBDTTPD films, pointing to important delocalization in those excitons. Then, we investigated the nature and local mobility (orders of magnitude higher than bulk mobility) of charges in the PBDTTPPD:PCBM blend as a function of excitation wavelength, fluence and pump-probe time delay. At low pump fluence (no bimolecular recombination phenomena), we were able to observe prompt and delayed charge generation components, the latter originating from excitons created in neat polymer domains which, thanks to delocalization, could reach the PCBM interface and dissociate to charges on a time scale of 1 ps. The nature of the photogenerated charges did not change between 0.5 ps and 800 ps after photo-excitation, which indicated that the excitons split directly into relatively free charges on an ultrafast time scale. © (2015) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

  10. High-resolution x-ray scattering studies of charge ordering in highly correlated electron systems

    CERN Document Server

    Ghazi, M E

    2002-01-01

    addition, another very weak satellites with wavevector (1/2, 1, 1/2) were observed possibly due to spin ordering. two-dimensional in nature both by measurements of their correlation lengths and by measurement of the critical exponents of the charge stripe melting transition with an anomaly at x = 0.25. The results show by decreasing the hole concentration from the x = 0.33 to 0.2, the well-correlated charge stripes change to a glassy state at x = 0.25. The electronic transition into the charge stripe phase is second-order without any corresponding structural transition. Above the second-order transition critical scattering was observed due to fluctuations into the charge stripe phase. In a single-crystal of Nd sub 1 sub / sub 2 Sr sub 1 sub / sub 2 MnO sub 3 a series of phase transitions were observed using high-resolution synchrotron X-ray scattering. Above the charge ordering transition temperature, T sub C sub O , by measuring the peak profiles of Bragg reflections as a function of temperature, it was foun...

  11. Impact of updraft on neutralized charge rate by lightning in thunderstorms: A simulation case study

    Science.gov (United States)

    Wang, Fei; Zhang, Yijun; Zheng, Dong

    2015-12-01

    The rate of neutralized charge by lightning (RNCL) is an important parameter indicating the intensity of lightning activity. The total charging rate (CR), the CR of one kind of polarity (e.g., negative) charge (CROP), and the outflow rate of charge on precipitation (ORCP) are proposed as key factors impacting RNCL, based on the principle of conservation of one kind of polarity charge in a thunderstorm. In this paper, the impacts of updraft on CR and CROP are analyzed by using a 3D cloud resolution model for a strong storm that occurred in Beijing on 6 september 2008. The results show that updraft both promotes and inhibits RNCL at the same time. (1) Updraft always has a positive influence on CR. The correlation coefficient between the updraft volume and CR can reach 0.96. Strengthening of the updraft facilitates strengthening of RNCL through this positive influence. (2) Strengthening of the updraft also promotes reinforcement of CROP. The correlation coefficient between the updraft volume and CROP is high (about 0.9), but this promotion restrains the strengthening of RNCL because the strengthening of CROP will, most of the time, inhibit the increasing of RNCL. (3) Additionally, increasing of ORCP depresses the strengthening of RNCL. In terms of magnitude, the peak of ORCP is equal to the peak of CR. Because precipitation mainly appears after the lightning activity finishes, the depression effect of ORCP on RNCL can be ignored during the active lightning period.

  12. Prevalence of myopia and its risk factors in urban school children in Delhi: the North India Myopia Study (NIM Study.

    Directory of Open Access Journals (Sweden)

    Rohit Saxena

    Full Text Available Assess prevalence of myopia and identify associated risk factors in urban school children.This was a cross-sectional study screening children for sub-normal vision and refractive errors in Delhi. Vision was tested by trained health workers using ETDRS charts. Risk factor questionnaire was filled for children with vision 11 years children (p 5 hours per day (p 2 hours / day (p 2 hours in a day.Myopia is a major health problem in Indian school children. It is important to identify modifiable risk factors associated with its development and try to develop cost effective intervention strategies.

  13. Effect of electrostatic charge in plastic spacers on the lung delivery of HFA-salbutamol in children

    DEFF Research Database (Denmark)

    Anhøj, J; Bisgaard, H; Lipworth, B J

    1999-01-01

    was delivered on 3 different study days from plastic spacers with mouthpiece. Pre-treatment of the spacers differed between study days: (a) Non-electrostatic 350 ml Babyhaler (coated with benzalkonium chloride) (b) New 350 ml Babyhaler (rinsed in water), and (c) New 145 ml AeroChamber (rinsed in water......). Plasma salbutamol was measured before and 5, 10, 15 and 20 min after inhalation of four single puffs of 100 microg salbutamol. Cmax and Cav (5-20min) were calculated as a reflection of lung dose. RESULTS: For Cmax: (A) Non-electrostatic Babyhaler 4.3 ng ml(-1) (B) New Babyhaler 1.9 ng ml(-1) (C) New AeroChamber...

  14. Decay of electric charge on corona charged polyethylene

    International Nuclear Information System (INIS)

    This paper describes a study on the surface potential decay of corona charged low density polyethylene (LDPE) films. A conventional corona charging process is used to deposit charge on the surface of film and surface potential is measured by a compact JCI 140 static monitor. The results from corona charged multilayer sample reveal that the bulk process dominates charge decay. In addition, the pulsed-electro-acoustic (PEA) technique has been employed to monitor charge profiles in corona charged LDPE films. By using the PEA technique, we are able to monitor charge migration through the bulk. Charge profiles in corona charged multilayer sample are consistent with surface potential results. Of further significance, the charge profiles clearly demonstrate that double injection has taken place in corona charged LDPE films

  15. Calculating potential of mean force between like-charged nanoparticles: a comprehensive study on salt effects

    CERN Document Server

    Wu, Yuan-Yan; Tan, Zhi-Jie

    2013-01-01

    Ions are critical to the structure and stability of polyelectrolytes such as nucleic acids. In this work, we systematically calculated the potentials of mean force between two like-charged nanoparticles in salt solutions by Monte Carlo simulations. The pseudo-spring method is employed to calculate the potential of mean force and compared systematically with the inversed-Boltzmann method. An effective attraction is predicted between two like-charged nanoparticles in divalent/trivalent salt solution and such attraction becomes weakened at very high salt concentration. Our analysis reveals that for the system, the configuration of ion-bridging nanoparticles is responsible for the attraction, and the invasion of anions into the inter-nanoparticles region at high salt concentration would induce attraction weakening rather than the charge inversion effect. The present method would be useful for calculating effective interactions during nucleic acid folding.

  16. Calculating potential of mean force between like-charged nanoparticles: A comprehensive study on salt effects

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Yuan-Yan; Wang, Feng-Hua; Tan, Zhi-Jie, E-mail: zjtan@whu.edu.cn

    2013-10-30

    Ions are critical to the structure and stability of polyelectrolytes such as nucleic acids. In this work, we systematically calculated the potentials of mean force between two like-charged nanoparticles in salt solutions by Monte Carlo simulations. The pseudo-spring method is employed to calculate the potential of mean force and compared systematically with the inversed-Boltzmann method. An effective attraction is predicted between two like-charged nanoparticles in divalent/trivalent salt solution and such attraction becomes weakened at very high salt concentration. Our analysis reveals that for the system, the configuration of ion-bridging nanoparticles is responsible for the attraction, and the invasion of anions into the inter-nanoparticles region at high salt concentration would induce attraction weakening rather than the charge inversion effect. The present method would be useful for calculating effective interactions during nucleic acid folding.

  17. 3D cylindrical silicon microdosimeters: fabrication, simulation and charge collection study

    International Nuclear Information System (INIS)

    This paper reports on the fabrication, simulation, and charge collection characteristics of a new generation of cylindrical silicon microdosimeters fabricated on SOI wafers. The devices consist of an array of p+ electrodes surrounded by trench n+ electrodes creating well defined, cylindrical sensitive volumes. A first batch of microsensors with 5.4 μm active thickness has been successfully fabricated. The devices are fully functional with good diode behavior and a depletion voltage of only 3 V. Their charge collection characteristics have been investigated using the IBIC technique with protons and alpha particles. The IBIC maps show a 100% yield of active cells in a microdosimeter array and full charge collection efficiency in the active area of the unit microsensors. These devices constitute an step forward in the current status of microdosimeters based on silicon technologies

  18. A study on the effects of relativistic heavy charged particles on the cellular microenvironment

    Science.gov (United States)

    Costes, Sylvain Vincent

    This study was done under the National Aeronautics Space Administration (NASA) effort to assess the effect of cosmic radiation on astronauts during a 3 year mission to Mars. Carcinogenesis is known to be induced more efficiently by cosmic radiation. Our attention was turned towards one of the most efficient cosmic particles in inducing cancer, relativistic Fe, and focused in assessing its effect on the cellular microenvironment (ECM). Previous observations on mammary glands were showing irregularities in the immunoreactivity of the ECM protein laminin one hour after whole body irradiation with 1GeV/amu Fe ions for a dose of 0.8 Gy. This effect was not observed after 5 Gy γ-rays exposure. The rapidity of such a change suggested that the effect might be due to a physical event specific to relativistic charged particles (HZE), rather than a biological event. Our study showed that this effect is actually a complex and rapid response of the microenvironment to highly ionizing radiation. It involves a fast disruption of the basement membrane of the ECM induced by the highly localized ionization and reactive oxygen formation around the track of the Fe ion. This disruption triggers further chemical and biological responses involved in the remodeling of the laminin network in the basement membrane. A metalloproteinase is suspected to be the intermediate protease affecting laminin. The HZE effect on the microenvironment was seen in both mouse mammary glands and skin, but the laminin isoforms sensitive to Fe ions were different for each organ, with a clear disruption of laminin-1 network in skin and of laminin-5 in mammary glands. In addition, the laminin receptor integrins seem to be involved in this mechanism, but its contribution is unclear at this point. Finally, such studies suggest a shift from the concept of relative biological effectiveness (RBE) used in classical radiation biology since the effect is only seen with HZE at viable whole body doses. In addition, this

  19. The art of the children of Terezin. A psychological study.

    Science.gov (United States)

    Gaezer Grossman, F

    1989-01-01

    This study is an analysis of the content and symbolism inherent in the art of children who were imprisoned in the Terezin Concentration Camp during the Holocaust. Its purpose is to attempt to understand how they perceived and sought to cope with the conditions of their lives at the camp, and to assess the degree of psychic damage suffered by them. The major themes are food, family and freedom, intense feelings of claustrophobia, a sense of the fragility of one's physical existence and the lack of human value of the camp inmates. Impressive is the absence of evidence of serious mental illness and aggression. It may be inferred that these manifestations did not have survival value. PMID:20684117

  20. A New Method to Study Hawking Radiation of Charged Particle from Stationary Axisymmetric Sen Black Hole

    Science.gov (United States)

    Yang, Shu-Zheng; Chen, De-You

    2007-01-01

    Taking the self-gravitation interaction and energy conservation, charge conservation and angular momentum conservation into account, we discuss the tunnelling characteristics of the charged particle from Sen black hole by the Hamilton-Jacobi method. The result shows that the tunnelling probability is related to the change of Bekenstein-Hawking entropy, and the actual radiation spectrum deviates from the pure thermal one, which is consistent with the result of Parikh and Wilczek and gives a new method to correct the Hawking pure thermal spectrum of Sen black hole.