WorldWideScience

Sample records for high loss environments

  1. High-fat diet causes bone loss in young mice by promoting osteoclastogenesis through alteration of the bone marrow environment.

    Science.gov (United States)

    Shu, Lei; Beier, Eric; Sheu, Tzong; Zhang, Hengwei; Zuscik, Michael J; Puzas, Edward J; Boyce, Brendan F; Mooney, Robert A; Xing, Lianping

    2015-04-01

    Obesity is a severe health problem in children, afflicting several organ systems including bone. However, the role of obesity on bone homeostasis and bone cell function in children has not been studied in detail. Here we used young mice fed a high-fat diet (HFD) to model childhood obesity and investigate the effect of HFD on the phenotype of cells within the bone marrow environment. Five-week-old male mice were fed a HFD for 3, 6, and 12 weeks. Decreased bone volume was detected after 3 weeks of HFD treatment. After 6 and 12 weeks, HFD-exposed mice had less bone mass and increased osteoclast numbers. Bone marrow cells, but not spleen cells, from HFD-fed mice had increased osteoclast precursor frequency, elevated osteoclast formation, and bone resorption activity, as well as increased expression of osteoclastogenic regulators including RANKL, TNF, and PPAR-gamma. Bone formation rate and osteoblast and adipocyte numbers were also increased in HFD-fed mice. Isolated bone marrow cells also had a corresponding elevation in the expression of positive regulators of osteoblast and adipocyte differentiation. Our findings indicate that in juvenile mice, HFD-induced bone loss is mainly due to increased osteoclast bone resorption by affecting the bone marrow microenvironment. Thus, targeting osteoclast formation may present a new therapeutic approach for bone complications in obese children.

  2. Severe signal loss in diamond beam loss monitors in high particle rate environments by charge trapping in radiation-induced defects

    Energy Technology Data Exchange (ETDEWEB)

    Kassel, Florian; Boer, Wim de [Institute for Experimental Nuclear Physics (IEKP), KIT, Karlsruhe (Germany); Guthoff, Moritz; Dabrowski, Anne [CERN, Meyrin (Switzerland)

    2016-10-15

    The beam condition monitoring leakage (BCML) system is a beam monitoring device in the compact muon solenoid (CMS) experiment at the large hadron collider (LHC). As detectors 32 poly-crystalline (pCVD) diamond sensors are positioned in rings around the beam pipe. Here, high particle rates occur from the colliding beams scattering particles outside the beam pipe. These particles cause defects, which act as traps for the ionization, thus reducing the charge collection efficiency (CCE). However, the loss in CCE was much more severe than expected from low rate laboratory measurements and simulations, especially in single-crystalline (sCVD) diamonds, which have a low initial concentration of defects. After an integrated luminosity of a few fb{sup -1} corresponding to a few weeks of LHC operation, the CCE of the sCVD diamonds dropped by a factor of five or more and quickly approached the poor CCE of pCVD diamonds. The reason why in real experiments the CCE is much worse than in laboratory experiments is related to the ionization rate. At high particle rates the trapping rate of the ionization is so high compared with the detrapping rate, that space charge builds up. This space charge reduces locally the internal electric field, which in turn increases the trapping rate and recombination and hence reduces the CCE in a strongly non-linear way. A diamond irradiation campaign was started to investigate the rate-dependent electrical field deformation with respect to the radiation damage. Besides the electrical field measurements via the transient current technique (TCT), the CCE was measured. The experimental results were used to create an effective deep trap model that takes the radiation damage into account. Using this trap model, the rate-dependent electrical field deformation and the CCE were simulated with the software SILVACO TCAD. The simulation, tuned to rate-dependent measurements from a strong radioactive source, was able to predict the non-linear decrease of the

  3. Severe signal loss in diamond beam loss monitors in high particle rate environments by charge trapping in radiation-induced defects

    CERN Document Server

    Kassel, Florian; Dabrowski, Anne; de Boer, Wim

    2016-01-01

    The beam condition monitoring leakage (BCML) system is a beam monitoring device in the compact muon solenoid (CMS) experiment at the large hadron collider (LHC). As detectors 32 poly-crystalline (pCVD) diamond sensors are positioned in rings around the beam pipe. Here, high particle rates occur from the colliding beams scattering particles outside the beam pipe. These particles cause defects, which act as traps for the ionization, thus reducing the charge collection efficiency (CCE). However, the loss in CCE was much more severe than expected from low rate laboratory measurements and simulations, especially in single-crystalline (sCVD) diamonds, which have a low initial concentration of defects. The reason why in real experiments the CCE is much worse than in laboratory experiments is related to the ionization rate. At high particle rates the trapping rate of the ionization is so high compared with the detrapping rate, that space charge builds up. This space charge reduces locally the internal electric field,...

  4. Production loss among employees perceiving work environment problems.

    Science.gov (United States)

    Lohela-Karlsson, Malin; Hagberg, Jan; Bergström, Gunnar

    2015-08-01

    The overall aim of this explorative study was to investigate the relationship between factors in the psychosocial work environment and work environment-related production loss. Employees at a Swedish university were invited to answer a workplace questionnaire and were selected for this study if they reported having experienced work environment-related problems in the past 7 days (n = 302). A stepwise logistic regression and a modified Poisson regression were used to identify psychosocial work factors associated with work environment-related production loss as well as to identify at what level those factors are associated with production loss. Employees who reported having experienced work environment problems but also fair leadership, good social climate, role clarity and control of decision had significantly lower levels of production loss, whereas employees who reported inequality and high decision demands reported significantly higher levels of production loss. Never or seldom experiencing fair leadership, role clarity, equality, decision demands and good social climate increase the risk of production loss due to work environment problems, compared to those who experience these circumstances frequently, always or most of the time. Several psychosocial work factors are identified as factors associated with a reduced risk of production losses among employees despite the nature of the work environment problem. Knowledge of these factors may be important not only to reduce employee ill-health and the corresponding health-related production loss, but also reduce immediate production loss due to work environment-related problems.

  5. AC loss in YBCO coated conductors at high dB/dt measured using a spinning magnet calorimeter (stator testbed environment)

    Science.gov (United States)

    Murphy, J. P.; Gheorghiu, N. N.; Bullard, T.; Haugan, T.; Sumption, M. D.; Majoros, M.; Collings, E. W.

    2017-09-01

    A new facility for the measurement of AC loss in superconductors at high dB/dt has been developed. The test device has a spinning rotor consisting of permanent magnets arranged in a Halbach array; the sample, positioned outside of this, is exposed to a time varying AC field with a peak radial field of 0.566 T. At a rotor speed of 3600 RPM the frequency of the AC field is 240 Hz, the radial dB/dt is 543 T/s and the tangential dB/dt is 249 T/s. Loss is measured using nitrogen boiloff from a double wall calorimeter feeding a gas flow meter. The system is calibrated using power from a known resistor. YBCO tape losses were measured in the new device and compared to the results from a solenoidal magnet AC loss system measurement of the same samples (in this latter case measurements were limited to a field of amplitude 0.1 T and a dB/dt of 100 T/s). Solenoidal magnet system AC loss measurements taken on a YBCO sample agreed with the Brandt loss expression associated with a 0-0.1 T Ic of 128 A. Subsequently, losses for two more YBCO tapes nominally identical to the first were individually measured in this spinning magnet calorimeter (SMC) machine with a Bmax of 0.566 T and dB/dt of up to 272 T/s. The losses, compared to a simplified version of the Brandt expression, were consistent with the average Ic expected for the tape in the 0-0.5 T range at 77 K. The eddy current contribution was consistent with a 77 K residual resistance ratio, RR, of 4.0. The SMC results for these samples agreed to within 5%. Good agreement was also obtained between the results of the SMC AC loss measurement and the solenoidal magnet AC loss measurement on the same samples.

  6. Respiratory heat loss of Holstein cows in a tropical environment

    Science.gov (United States)

    Campos Maia, Alex Sandro; Gomes Dasilva, Roberto; Battiston Loureiro, Cintia Maria

    2005-05-01

    In order to develop statistical models to predict respiratory heat loss in dairy cattle using simple physiological and environmental measurements, 15 Holstein cows were observed under field conditions in a tropical environment, in which the air temperature reached up to 40°C. The measurements of latent and sensible heat loss from the respiratory tract of the animals were made by using a respiratory mask. The results showed that under air temperatures between 10 and 35°C sensible heat loss by convection decreased from 8.24 to 1.09 W m-2, while the latent heat loss by evaporation increased from 1.03 to 56.51 W m-2. The evaporation increased together with the air temperature in almost a linear fashion until 20°C, but it became increasingly high as the air temperature rose above 25°C. Convection was a mechanism of minor importance for respiratory heat transfer. In contrast, respiratory evaporation was an effective means of thermoregulation for Holsteins in a hot environment. Mathematical models were developed to predict both the sensible and latent heat loss from the respiratory tract in Holstein cows under field conditions, based on measurements of the ambient temperature, and other models were developed to predict respiration rate, tidal volume, mass flow rate and expired air temperature as functions of the ambient temperature and other variables.

  7. Cutaneous water loss and sphingolipids in the stratum corneum of house sparrows, Passer domesticus L., from desert and mesic environments as determined by reversed phase high-performance liquid chromatography coupled with atmospheric pressure photospray ionization mass spectrometry.

    Science.gov (United States)

    Muñoz-Garcia, Agustí; Ro, Jennifer; Brown, Johnie C; Williams, Joseph B

    2008-02-01

    Because cutaneous water loss (CWL) represents half of total water loss in birds, selection to reduce CWL may be strong in desert birds. We previously found that CWL of house sparrows from a desert population was about 25% lower than that of individuals from a mesic environment. The stratum corneum (SC), the outer layer of the epidermis, serves as the primary barrier to water vapor diffusion through the skin. The avian SC is formed by layers of corneocytes embedded in a lipid matrix consisting of cholesterol, free fatty acids and two classes of sphingolipids, ceramides and cerebrosides. The SC of birds also serves a thermoregulatory function; high rates of CWL keep body temperatures under lethal limits in episodes of heat stress. In this study, we used high-performance liquid chromatography coupled with atmospheric pressure photoionization-mass spectrometry (HPLC/APPI-MS) to identify and quantify over 200 sphingolipids in the SC of house sparrows from desert and mesic populations. Principal components analysis (PCA) led to the hypotheses that sphingolipids in the SC of desert sparrows have longer carbon chains in the fatty acid moiety and are more polar than those found in mesic sparrows. We also tested the association between principal components and CWL in both populations. Our study suggested that a reduction in CWL found in desert sparrows was, in part, the result of modifications in chain length and polarity of the sphingolipids, changes that apparently determine the interactions of the lipid molecules within the SC.

  8. QoE loss score value for service migration in context aware environment

    DEFF Research Database (Denmark)

    Saeed, Aamir; Pedersen, Jens Myrup; Olsen, Rasmus Løvenstein

    2014-01-01

    The increasing amount of smart devices and handheld devices have widened the amount of information presence all over. The application running on one device can be distributed to a surrounding device for better functionality. A capability that might be enjoyable or frustrating for end user....... This paper has identified the factors that contribute to the loss of user experience for seamless application migration in a context aware environment. These are the context information updates, transfer time and resumption time. To quantify the loss of user experience, a Quality of experience (QoE) Loss...... score value (representing the time that is lost in user experience during migrating process)is introduced. A high QoE loss score value indicates a higher loss of user experience and a lower QoE loss score value indicate a lower loss of user experience. A test-bed setup was implemented and different...

  9. RF Path and Absorption Loss Estimation for Underwater Wireless Sensor Networks in Different Water Environments.

    Science.gov (United States)

    Qureshi, Umair Mujtaba; Shaikh, Faisal Karim; Aziz, Zuneera; Shah, Syed M Zafi S; Sheikh, Adil A; Felemban, Emad; Qaisar, Saad Bin

    2016-06-16

    Underwater Wireless Sensor Network (UWSN) communication at high frequencies is extremely challenging. The intricacies presented by the underwater environment are far more compared to the terrestrial environment. The prime reason for such intricacies are the physical characteristics of the underwater environment that have a big impact on electromagnetic (EM) signals. Acoustics signals are by far the most preferred choice for underwater wireless communication. Because high frequency signals have the luxury of large bandwidth (BW) at shorter distances, high frequency EM signals cannot penetrate and propagate deep in underwater environments. The EM properties of water tend to resist their propagation and cause severe attenuation. Accordingly, there are two questions that need to be addressed for underwater environment, first what happens when high frequency EM signals operating at 2.4 GHz are used for communication, and second which factors affect the most to high frequency EM signals. To answer these questions, we present real-time experiments conducted at 2.4 GHz in terrestrial and underwater (fresh water) environments. The obtained results helped in studying the physical characteristics (i.e., EM properties, propagation and absorption loss) of underwater environments. It is observed that high frequency EM signals can propagate in fresh water at a shallow depth only and can be considered for a specific class of applications such as water sports. Furthermore, path loss, velocity of propagation, absorption loss and the rate of signal loss in different underwater environments are also calculated and presented in order to understand why EM signals cannot propagate in sea water and oceanic water environments. An optimal solk6ution for underwater communication in terms of coverage distance, bandwidth and nature of communication is presented, along with possible underwater applications of UWSNs at 2.4 GHz.

  10. RF Path and Absorption Loss Estimation for Underwater Wireless Sensor Networks in Different Water Environments

    Directory of Open Access Journals (Sweden)

    Umair Mujtaba Qureshi

    2016-06-01

    Full Text Available Underwater Wireless Sensor Network (UWSN communication at high frequencies is extremely challenging. The intricacies presented by the underwater environment are far more compared to the terrestrial environment. The prime reason for such intricacies are the physical characteristics of the underwater environment that have a big impact on electromagnetic (EM signals. Acoustics signals are by far the most preferred choice for underwater wireless communication. Because high frequency signals have the luxury of large bandwidth (BW at shorter distances, high frequency EM signals cannot penetrate and propagate deep in underwater environments. The EM properties of water tend to resist their propagation and cause severe attenuation. Accordingly, there are two questions that need to be addressed for underwater environment, first what happens when high frequency EM signals operating at 2.4 GHz are used for communication, and second which factors affect the most to high frequency EM signals. To answer these questions, we present real-time experiments conducted at 2.4 GHz in terrestrial and underwater (fresh water environments. The obtained results helped in studying the physical characteristics (i.e., EM properties, propagation and absorption loss of underwater environments. It is observed that high frequency EM signals can propagate in fresh water at a shallow depth only and can be considered for a specific class of applications such as water sports. Furthermore, path loss, velocity of propagation, absorption loss and the rate of signal loss in different underwater environments are also calculated and presented in order to understand why EM signals cannot propagate in sea water and oceanic water environments. An optimal solk6ution for underwater communication in terms of coverage distance, bandwidth and nature of communication is presented, along with possible underwater applications of UWSNs at 2.4 GHz.

  11. Coping with Hearing Loss and High School

    Science.gov (United States)

    Exceptional Parent, 2010

    2010-01-01

    High school can be a bumpy road for teenagers, especially since most teenagers are trying to fit in and start to define their own individuality and future. Now imagine if a teenager has hearing loss. Besides not being able to hear their instructors or friends as well as their classmates, self image problems can be magnified if they need to wear…

  12. Thermal Loss in High-Q Antennas

    DEFF Research Database (Denmark)

    Barrio, Samantha Caporal Del; Bahramzy, Pevand; Svendsen, Simon

    2014-01-01

    Tunable antennas are very promising for future generations of mobile communications, where antennas are required to cover a wide range operating bands. This letter aims at characterizing the loss mechanism of tunable antennas. Tunable antennas typically exhibit a high Quality factor (Q), which can...

  13. 'High-risk' pregnancy after perinatal loss: understanding the label.

    Science.gov (United States)

    Simmons, Heather A; Goldberg, Lisa S

    2011-08-01

    to explore women's experience of living with a 'high-risk' pregnancy following a perinatal loss. a feminist phenomenological methodology provided the framework for the research study. the experience of 'high-risk' pregnancy following perinatal loss of seven women receiving care at a tertiary health centre in Atlantic Canada was explored by way of conversational interviews and reflective journaling. four themes emerged through thematic analysis and researcher interpretation: (1) understanding the meaning in the label of 'high-risk' pregnancy, (2) relational engagement with the unborn infant, (3) insight and acceptance of the influence of previous loss, and (4) essentiality of information. Taken together, these four themes represent the storied text embedded in the research study. The focus of attention in this article is based solely on the first theme, understanding the meaning in the label of 'high-risk' pregnancy, in so far as this fosters an ability to attend to the interpretive text in the methodological manner appropriate to phenomenological inquiry. although previous research indicates that the label of 'high-risk' in pregnancy is often associated with increased anxiety and fear, findings from this study suggest that a 'high-risk' pregnancy following perinatal loss results in women embracing the 'high-risk' label. By recognising the possibility that women experiencing 'high-risk' pregnancy following perinatal loss may perceive the label of 'high-risk' pregnancy in a positive way, nurses, midwives and other health-care providers may begin to alter their practices when caring for these women in current health-care environments. Copyright © 2010 Elsevier Ltd. All rights reserved.

  14. Evaporative water loss in man in a gravity-free environment

    Science.gov (United States)

    Leach, C. S.; Leonard, J. I.; Rambaut, P. C.; Johnson, P. C.

    1978-01-01

    Daily evaporative water losses (EWL) during the three Skylab missions were measured indirectly using mass and water-balance techniques. The mean daily values of EWL for the nine crew members who averaged 1 hr of daily exercise were: preflight 1,750 + or - 37 (SE) ml or 970 + or - 20 ml/sq m and inflight 1,560 + or - 26 ml or 860 + or - 14 ml/sq m. Although it was expected the EWL would increase in the hypobaric environment of Skylab, an average decrease from preflight sea-level conditions of 11% was measured. The results suggest that weightlessness decreased sweat losses during exercise and possibly reduced insensible skin losses. The weightlessness environment apparently promotes the formation of an observed sweat film on the skin surface during exercise by reducing convective flow and sweat drippage, resulting in high levels of skin wettedness that favor sweat suppression.

  15. Measuring production loss due to health and work environment problems: construct validity and implications.

    Science.gov (United States)

    Karlsson, Malin Lohela; Bergström, Gunnar; Björklund, Christina; Hagberg, Jan; Jensen, Irene

    2013-12-01

    The aim was to validate two measures of production loss, health-related and work environment-related production loss, concerning their associations with health status and work environment factors. Validity was assessed by evaluating the construct validity. Health problems related and work environment-related problems (or factors) were included in separate analyses and evaluated regarding the significant difference in proportion of explained variation (R) of production loss. health problems production loss was not found to fulfill the criteria for convergent validity in this study; however, the measure of work environment-related production loss did fulfill the criteria that were set up. The measure of work environment-related production loss can be used to screen for production loss due to work environment problems as well as an outcome measure when evaluating the effect of organizational interventions.

  16. Automated Screening for High-Frequency Hearing Loss

    NARCIS (Netherlands)

    Vlaming, M.S.M.G.; MacKinnon, R.C.; Jansen, M.; Moore, D.R.

    2014-01-01

    OBJECTIVE: Hearing loss at high frequencies produces perceptual difficulties and is often an early sign of a more general hearing loss. This study reports the development and validation of two new speech-based hearing screening tests in English that focus on detecting hearing loss at frequencies

  17. Verifying cell loss requirements in high-speed communication networks

    Directory of Open Access Journals (Sweden)

    Kerry W. Fendick

    1998-01-01

    Full Text Available In high-speed communication networks it is common to have requirements of very small cell loss probabilities due to buffer overflow. Losses are measured to verify that the cell loss requirements are being met, but it is not clear how to interpret such measurements. We propose methods for determining whether or not cell loss requirements are being met. A key idea is to look at the stream of losses as successive clusters of losses. Often clusters of losses, rather than individual losses, should be regarded as the important “loss events”. Thus we propose modeling the cell loss process by a batch Poisson stochastic process. Successive clusters of losses are assumed to arrive according to a Poisson process. Within each cluster, cell losses do not occur at a single time, but the distance between losses within a cluster should be negligible compared to the distance between clusters. Thus, for the purpose of estimating the cell loss probability, we ignore the spaces between successive cell losses in a cluster of losses. Asymptotic theory suggests that the counting process of losses initiating clusters often should be approximately a Poisson process even though the cell arrival process is not nearly Poisson. The batch Poisson model is relatively easy to test statistically and fit; e.g., the batch-size distribution and the batch arrival rate can readily be estimated from cell loss data. Since batch (cluster sizes may be highly variable, it may be useful to focus on the number of batches instead of the number of cells in a measurement interval. We also propose a method for approximately determining the parameters of a special batch Poisson cell loss with geometric batch-size distribution from a queueing model of the buffer content. For this step, we use a reflected Brownian motion (RBM approximation of a G/D/1/C queueing model. We also use the RBM model to estimate the input burstiness given the cell loss rate. In addition, we use the RBM model to

  18. Quantum Key Distribution with High Loss: Toward Global Secure Communication

    Science.gov (United States)

    Hwang, Won-Young

    2003-08-01

    We propose a decoy-pulse method to overcome the photon-number-splitting attack for Bennett-Brassard 1984 quantum key distribution protocol in the presence of high loss: A legitimate user intentionally and randomly replaces signal pulses by multiphoton pulses (decoy pulses). Then they check the loss of the decoy pulses. If the loss of the decoy pulses is abnormally less than that of signal pulses, the whole protocol is aborted. Otherwise, to continue the protocol, they estimate the loss of signal multiphoton pulses based on that of decoy pulses. This estimation can be done with an assumption that the two losses have similar values. We justify that assumption.

  19. Detonation propagation in a high loss configuration

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, Scott I [Los Alamos National Laboratory; Shepherd, Joseph E [CALTECH

    2009-01-01

    This work presents an experimental study of detonation wave propagation in tubes with inner diameters (ID) comparable to the mixture cell size. Propane-oxygen mixtures were used in two test section tubes with inner diameters of 1.27 mm and 6.35 mm. For both test sections, the initial pressure of stoichiometric mixtures was varied to determine the effect on detonation propagation. For the 6.35 mm tube, the equivalence ratio {phi} (where the mixture was {phi} C{sub 3}H{sub 8} + 50{sub 2}) was also varied. Detonations were found to propagate in mixtures with cell sizes as large as five times the diameter of the tube. However, under these conditions, significant losses were observed, resulting in wave propagation velocities as slow as 40% of the CJ velocity U{sub CJ}. A review of relevant literature is presented, followed by experimental details and data. Observed velocity deficits are predicted using models that account for boundary layer growth inside detonation waves.

  20. Method to prevent recession loss of silica and silicon-containing materials in combustion gas environments

    Science.gov (United States)

    Brun, Milivoj Konstantin; Luthra, Krishan Lal

    2003-01-01

    While silicon-containing ceramics or ceramic composites are prone to material loss in combustion gas environments, this invention introduces a method to prevent or greatly reduce the thickness loss by injecting directly an effective amount, generally in the part per million level, of silicon or silicon-containing compounds into the combustion gases.

  1. Scientific Visualization in High Speed Network Environments

    Science.gov (United States)

    Vaziri, Arsi; Kutler, Paul (Technical Monitor)

    1997-01-01

    In several cases, new visualization techniques have vastly increased the researcher's ability to analyze and comprehend data. Similarly, the role of networks in providing an efficient supercomputing environment have become more critical and continue to grow at a faster rate than the increase in the processing capabilities of supercomputers. A close relationship between scientific visualization and high-speed networks in providing an important link to support efficient supercomputing is identified. The two technologies are driven by the increasing complexities and volume of supercomputer data. The interaction of scientific visualization and high-speed networks in a Computational Fluid Dynamics simulation/visualization environment are given. Current capabilities supported by high speed networks, supercomputers, and high-performance graphics workstations at the Numerical Aerodynamic Simulation Facility (NAS) at NASA Ames Research Center are described. Applied research in providing a supercomputer visualization environment to support future computational requirements are summarized.

  2. Impact of indoor environment on path loss in body area networks.

    Science.gov (United States)

    Hausman, Sławomir; Januszkiewicz, Łukasz

    2014-10-20

    In this paper the influence of an example indoor environment on narrowband radio channel path loss for body area networks operating around 2.4 GHz is investigated using computer simulations and on-site measurements. In contrast to other similar studies, the simulation model included both a numerical human body phantom and its environment-room walls, floor and ceiling. As an example, radio signal attenuation between two different configurations of transceivers with dipole antennas placed in a direct vicinity of a human body (on-body scenario) is analyzed by computer simulations for several types of reflecting environments. In the analyzed case the propagation environments comprised a human body and office room walls. As a reference environment for comparison, free space with only a conducting ground plane, modelling a steel mesh reinforced concrete floor, was chosen. The transmitting and receiving antennas were placed in two on-body configurations chest-back and chest-arm. Path loss vs. frequency simulation results obtained using Finite Difference Time Domain (FDTD) method and a multi-tissue anthropomorphic phantom were compared to results of measurements taken with a vector network analyzer with a human subject located in an average-size empty cuboidal office room. A comparison of path loss values in different environments variants gives some qualitative and quantitative insight into the adequacy of simplified indoor environment model for the indoor body area network channel representation.

  3. Automated Screening for High-Frequency Hearing Loss

    OpenAIRE

    Vlaming, Marcel S M G; Mackinnon, Robert C.; Jansen, Marije; Moore, David R.

    2014-01-01

    OBJECTIVE: Hearing loss at high frequencies produces perceptual difficulties and is often an early sign of a more general hearing loss. This study reports the development and validation of two new speech-based hearing screening tests in English that focus on detecting hearing loss at frequencies above 2000 Hz. DESIGN: The Internet-delivered, speech-in noise tests used closed target-word sets of digit triplets or consonant-vowel-consonant (CVC) words presented against a speech-shaped noise mas...

  4. A Practical Radiosity Method for Predicting Transmission Loss in Urban Environments

    Directory of Open Access Journals (Sweden)

    Liang Ming

    2004-01-01

    Full Text Available The ability to predict transmission loss or field strength distribution is crucial for determining coverage in planning personal communication systems. This paper presents a practical method to accurately predict entire average transmission loss distribution in complicated urban environments. The method uses a 3D propagation model based on radiosity and a simplified city information database including surfaces of roads and building groups. Narrowband validation measurements with line-of-sight (LOS and non-line-of-sight (NLOS cases at 1800 MHz give excellent agreement in urban environments.

  5. Low Loss High Isolation NEMS/MEMS Switch for High Frequency RF Applications

    Directory of Open Access Journals (Sweden)

    Elangovan R.

    2015-03-01

    Full Text Available MEMS switches are advantageous in terms of low power consumption, switching times, high isolation, low insertion loss and many more. This paper proposes a MEMS switch with high isolation and low insertion loss. The model used is a CPW configuration with a cantilever series switch built on a silicon substrate. The switch parameters are optimized for the lowest insertion loss and return loss. An insertion loss values of -0.1305 dB in the down state with return loss of -38 dB and -75 dB of isolation have been observed in the high frequency range.

  6. Ain't no mountain high enough? Setting high weight loss goals predict effort and short-term weight loss.

    Science.gov (United States)

    De Vet, Emely; Nelissen, Rob M A; Zeelenberg, Marcel; De Ridder, Denise T D

    2013-05-01

    Although psychological theories outline that it might be beneficial to set more challenging goals, people attempting to lose weight are generally recommended to set modest weight loss goals. The present study explores whether the amount of weight loss individuals strive for is associated with more positive psychological and behavioral outcomes. Hereto, 447 overweight and obese participants trying to lose weight completed two questionnaires with a 2-month interval. Many participants set goals that could be considered unrealistically high. However, higher weight loss goals did not predict dissatisfaction but predicted more effort in the weight loss attempt, as well as more self-reported short-term weight loss when baseline commitment and motivation were controlled for.

  7. Impact of Indoor Environment on Path Loss in Body Area Networks

    Science.gov (United States)

    Hausman, Sławomir; Januszkiewicz, Łukasz

    2014-01-01

    In this paper the influence of an example indoor environment on narrowband radio channel path loss for body area networks operating around 2.4 GHz is investigated using computer simulations and on-site measurements. In contrast to other similar studies, the simulation model included both a numerical human body phantom and its environment—room walls, floor and ceiling. As an example, radio signal attenuation between two different configurations of transceivers with dipole antennas placed in a direct vicinity of a human body (on-body scenario) is analyzed by computer simulations for several types of reflecting environments. In the analyzed case the propagation environments comprised a human body and office room walls. As a reference environment for comparison, free space with only a conducting ground plane, modelling a steel mesh reinforced concrete floor, was chosen. The transmitting and receiving antennas were placed in two on-body configurations chest–back and chest–arm. Path loss vs. frequency simulation results obtained using Finite Difference Time Domain (FDTD) method and a multi-tissue anthropomorphic phantom were compared to results of measurements taken with a vector network analyzer with a human subject located in an average-size empty cuboidal office room. A comparison of path loss values in different environments variants gives some qualitative and quantitative insight into the adequacy of simplified indoor environment model for the indoor body area network channel representation. PMID:25333289

  8. Impact of Indoor Environment on Path Loss in Body Area Networks

    Directory of Open Access Journals (Sweden)

    Sławomir Hausman

    2014-10-01

    Full Text Available In this paper the influence of an example indoor environment on narrowband radio channel path loss for body area networks operating around 2.4 GHz is investigated using computer simulations and on-site measurements. In contrast to other similar studies, the simulation model included both a numerical human body phantom and its environment—room walls, floor and ceiling. As an example, radio signal attenuation between two different configurations of transceivers with dipole antennas placed in a direct vicinity of a human body (on-body scenario is analyzed by computer simulations for several types of reflecting environments. In the analyzed case the propagation environments comprised a human body and office room walls. As a reference environment for comparison, free space with only a conducting ground plane, modelling a steel mesh reinforced concrete floor, was chosen. The transmitting and receiving antennas were placed in two on-body configurations chest–back and chest–arm. Path loss vs. frequency simulation results obtained using Finite Difference Time Domain (FDTD method and a multi-tissue anthropomorphic phantom were compared to results of measurements taken with a vector network analyzer with a human subject located in an average-size empty cuboidal office room. A comparison of path loss values in different environments variants gives some qualitative and quantitative insight into the adequacy of simplified indoor environment model for the indoor body area network channel representation.

  9. A New GIS-Nitrogen Trading Tool Concept to Minimize Reactive Nitrogen losses to the Environment

    Science.gov (United States)

    Nitrogen (N) is an essential element which is needed to maximize agricultural production and sustainability of worldwide agroecosystems. N losses to the environment are impacting water and air quality that has become an environmental concern for the future generations. It has led to the need for dev...

  10. Fermilab main injector: High intensity operation and beam loss control

    Directory of Open Access Journals (Sweden)

    Bruce C. Brown

    2013-07-01

    Full Text Available From 2005 through 2012, the Fermilab Main Injector provided intense beams of 120 GeV protons to produce neutrino beams and antiprotons. Hardware improvements in conjunction with improved diagnostics allowed the system to reach sustained operation at 400 kW beam power. Transmission was very high except for beam lost at or near the 8 GeV injection energy where 95% beam transmission results in about 1.5 kW of beam loss. By minimizing and localizing loss, residual radiation levels fell while beam power was doubled. Lost beam was directed to either the collimation system or to the beam abort. Critical apertures were increased while improved instrumentation allowed optimal use of available apertures. We will summarize the improvements required to achieve high intensity, the impact of various loss control tools and the status and trends in residual radiation in the Main Injector.

  11. Sensible and latent heat loss from the body surface of Holstein cows in a tropical environment

    Science.gov (United States)

    Maia, A. S. C.; Dasilva, R. G.; Battiston Loureiro, C. M.

    2005-09-01

    The general principles of the mechanisms of heat transfer are well known, but knowledge of the transition between evaporative and non-evaporative heat loss by Holstein cows in field conditions must be improved, especially for low-latitude environments. With this aim 15 Holstein cows managed in open pasture were observed in a tropical region. The latent heat loss from the body surface of the animals was measured by means of a ventilated capsule, while convective heat transfer was estimated by the theory of convection from a horizontal cylinder and by the long-wave radiation exchange based on the Stefan-Boltzmann law. When the air temperature was between 10 and 36°C the sensible heat transfer varied from 160 to -30 W m-2, while the latent heat loss by cutaneous evaporation increased from 30 to 350 W m-2. Heat loss by cutaneous evaporation accounted for 20-30% of the total heat loss when air temperatures ranged from 10 to 20°C. At air temperatures >30°C cutaneous evaporation becomes the main avenue of heat loss, accounting for approximately 85% of the total heat loss, while the rest is lost by respiratory evaporation.

  12. Teaching about Loss and Death to Junior High School Students.

    Science.gov (United States)

    Moore, Christine M.

    1989-01-01

    Presents educational unit on death and loss designed to help junior high school students better understand themselves and their world and develop skills required for coping positively with stressful life events. Includes brief explanations for each of eight course themes and descriptions of major classroom activities. (Author/NB)

  13. Automated screening for high-frequency hearing loss.

    Science.gov (United States)

    Vlaming, Marcel S M G; MacKinnon, Robert C; Jansen, Marije; Moore, David R

    2014-01-01

    Hearing loss at high frequencies produces perceptual difficulties and is often an early sign of a more general hearing loss. This study reports the development and validation of two new speech-based hearing screening tests in English that focus on detecting hearing loss at frequencies above 2000 Hz. The Internet-delivered, speech-in noise tests used closed target-word sets of digit triplets or consonant-vowel-consonant (CVC) words presented against a speech-shaped noise masker. The digit triplet test uses the digits 0 to 9 (excluding the disyllabic 7), grouped in quasi-random triplets. The CVC test uses simple words (e.g., "cat") selected for the high-frequency spectral content of the consonants. During testing, triplets or CVC words were identified in an adaptive procedure to obtain the speech reception threshold (SRT) in noise. For these new, high-frequency (HF) tests, the noise was low-pass filtered to produce greater masking of the low-frequency speech components, increasing the sensitivity of the test for HF hearing loss. Individual test tokens (digits, CVCs) were first homogenized using a group of 10 normal-hearing (NH) listeners by equalizing intelligibility across tokens at several speech-in-noise levels. Both tests were then validated and standardized using groups of 24 NH listeners and 50 listeners with hearing impairment. Performance on the new high frequency digit triplet (HF-triplet) and CVC (HF-CVC) tests was compared with audiometric hearing loss, and with that on the unfiltered, broadband digit triplet test (BB-triplet) test, and the ASL (Adaptive Sentence Lists) speech-in-noise test. The HF-triplet and HF-CVC test results (SRT) both correlated positively and highly with high-frequency audiometric hearing loss and with the ASL test. SRT for both tests as a function of high-frequency hearing loss increased at nearly three times the rate as that of the BB-triplet test. The intraindividual variability (SD) on the tests was about 2.1 (HF-triplet) and 1

  14. Home grocery delivery improves the household food environments of behavioral weight loss participants: Results of an 8-week pilot study

    Directory of Open Access Journals (Sweden)

    Niemeier Heather M

    2007-11-01

    Full Text Available Abstract Background Household food availability is consistently linked to dietary intake; yet behavioral weight control treatment includes only minimal instruction on how to change the home environment to support dietary goals. This pilot study examined whether it is feasible to change the household food environments of behavioral weight loss participants through the use of a commercially available grocery home delivery service. Methods Overweight participants (N = 28; BMI = 31.7 ± 3.6 kg/m2; 89.3% women, 47.9 ± 9.5 years were randomly assigned to 8-weeks of standard behavioral weight loss (SBT or to SBT plus home food delivery (SBT+Home. SBT+Home participants were instructed to do their household grocery shopping via an online service affiliated with a regional supermarket chain and were reimbursed for delivery charges. Results Compared to SBT, SBT+Home produced significantly greater reductions in the total number of foods in the home (p = .01 and number of foods that were high in fat (p = .002. While the groups did not differ in 8-week weight losses, within SBT+Home there was a trend for the number of home deliveries to be associated with weight loss (p = .08. Participants reported that the home delivery service was easy to use and that it helped decrease impulse purchases and lead to healthier choices; however, few planned to continue using the service after the study. Conclusion Encouraging weight loss participants to use a commercially available online grocery ordering and home delivery service reduces the overall number of food items in the home and decreases access to high-fat food choices. More research is needed to determine whether this is a viable strategy to strengthen stimulus control and improve weight loss outcomes.

  15. Home grocery delivery improves the household food environments of behavioral weight loss participants: results of an 8-week pilot study.

    Science.gov (United States)

    Gorin, Amy A; Raynor, Hollie A; Niemeier, Heather M; Wing, Rena R

    2007-11-14

    Household food availability is consistently linked to dietary intake; yet behavioral weight control treatment includes only minimal instruction on how to change the home environment to support dietary goals. This pilot study examined whether it is feasible to change the household food environments of behavioral weight loss participants through the use of a commercially available grocery home delivery service. Overweight participants (N = 28; BMI = 31.7 +/- 3.6 kg/m2; 89.3% women, 47.9 +/- 9.5 years) were randomly assigned to 8-weeks of standard behavioral weight loss (SBT) or to SBT plus home food delivery (SBT+Home). SBT+Home participants were instructed to do their household grocery shopping via an online service affiliated with a regional supermarket chain and were reimbursed for delivery charges. Compared to SBT, SBT+Home produced significantly greater reductions in the total number of foods in the home (p = .01) and number of foods that were high in fat (p = .002). While the groups did not differ in 8-week weight losses, within SBT+Home there was a trend for the number of home deliveries to be associated with weight loss (p = .08). Participants reported that the home delivery service was easy to use and that it helped decrease impulse purchases and lead to healthier choices; however, few planned to continue using the service after the study. Encouraging weight loss participants to use a commercially available online grocery ordering and home delivery service reduces the overall number of food items in the home and decreases access to high-fat food choices. More research is needed to determine whether this is a viable strategy to strengthen stimulus control and improve weight loss outcomes.

  16. Home grocery delivery improves the household food environments of behavioral weight loss participants: Results of an 8-week pilot study

    Science.gov (United States)

    Gorin, Amy A; Raynor, Hollie A; Niemeier, Heather M; Wing, Rena R

    2007-01-01

    Background Household food availability is consistently linked to dietary intake; yet behavioral weight control treatment includes only minimal instruction on how to change the home environment to support dietary goals. This pilot study examined whether it is feasible to change the household food environments of behavioral weight loss participants through the use of a commercially available grocery home delivery service. Methods Overweight participants (N = 28; BMI = 31.7 ± 3.6 kg/m2; 89.3% women, 47.9 ± 9.5 years) were randomly assigned to 8-weeks of standard behavioral weight loss (SBT) or to SBT plus home food delivery (SBT+Home). SBT+Home participants were instructed to do their household grocery shopping via an online service affiliated with a regional supermarket chain and were reimbursed for delivery charges. Results Compared to SBT, SBT+Home produced significantly greater reductions in the total number of foods in the home (p = .01) and number of foods that were high in fat (p = .002). While the groups did not differ in 8-week weight losses, within SBT+Home there was a trend for the number of home deliveries to be associated with weight loss (p = .08). Participants reported that the home delivery service was easy to use and that it helped decrease impulse purchases and lead to healthier choices; however, few planned to continue using the service after the study. Conclusion Encouraging weight loss participants to use a commercially available online grocery ordering and home delivery service reduces the overall number of food items in the home and decreases access to high-fat food choices. More research is needed to determine whether this is a viable strategy to strengthen stimulus control and improve weight loss outcomes. PMID:18001469

  17. Microdroplet-etched highly birefringent low-loss fiber tapers.

    Science.gov (United States)

    Mikkelsen, Jared C; Poon, Joyce K S

    2012-07-01

    We use hydrofluoric acid microdroplets to directly etch highly birefringent biconical fiber tapers from standard single-mode fibers. The fiber tapers have micrometer-sized cross sections, which are controlled by the etching condition. The characteristic teardrop cross section leads to a high group birefringence of B(G)≈0.017 and insertion losses <0.7 dB over waist lengths of about 2.1 mm.

  18. Origin of high propagation loss in electrospun polymer nanofibers

    Science.gov (United States)

    Ishii, Yuya; Satozono, Shota; Kaminose, Ryohei; Fukuda, Mitsuo

    2014-06-01

    We evaluate optical propagation loss (α) in electrospun poly(methyl methacrylate) (PMMA) nanofibers with different wavelength (λ) and determine the origin of the loss. Aligned single electrospun nanofibers composed of PMMA and a small amount of an organic dye are fabricated with an average diameter of approximately 640 nm. After cladding seven fiber samples, α is evaluated to be 26-62 dB cm-1 at wavelengths 590-680 nm. Moreover, α depended linearly on λ-4, and from the fitting functions we determined the ratio of the following two possible losses for α: loss at the interface between the fiber-core and cladding because of non-uniformity within the fibers (αun), and loss because of excess light scattering in the fibers resulting from density inhomogeneity of PMMA (αsc). For the fibers, αun is evaluated to be 6.9-22 dB cm-1, which represents 19%-50% of α at λ of 650 nm with α ˜ αun + αsc. Thus, we conclude that the high α in these fibers originates from both their poor uniformity and density inhomogeneity. Furthermore, a quantitative investigation of uniformity in the individual fibers revealed that the root mean square roughness ranges from 5.5 nm to 9.0 nm and the theoretical value of αun was ˜1 dB cm-1 showing reasonable agreement with experimental data. These findings hold for low-loss polymer nanofiber waveguides, which have high aspect ratio and fine patterning even in three dimensions.

  19. Losses to the environment from the multilevel cycle of anthropogenic lead

    Energy Technology Data Exchange (ETDEWEB)

    Mao, J.S. [State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875 (China); Cao, J. [Center of Industrial Ecology, Yale University, 195 Prospect Street, New Haven, CT 06511 (United States); Graedel, T.E., E-mail: thomas.graedel@yale.ed [Center of Industrial Ecology, Yale University, 195 Prospect Street, New Haven, CT 06511 (United States)

    2009-10-15

    As a component of a multi-level study of the anthropogenic lead cycle for year 2000 (52 countries, 8 regions, and the planet), we have estimated the lead flows in seven emission streams: tailings, slag, fabrication and manufacturing, dissipation from use, hibernation, landfilling, and dispersion following product discard. For every 1 kg of lead put into end use, 0.5 kg is lost to the environment, largely due to landfilling and dissipation from use. From the standpoint of the receiving media, 1/3 of the losses are to uncontained solids on land and 48% of the losses are to containment facilities on land. On a country basis, the largest losses occur in the United States and China, which between them are responsible for about 32% of total global lead losses. On a per capita basis, the highest lead losses occurred in the United Kingdom, Belgium-Luxembourg, and Ireland. - Estimates of lead losses in different emission streams in 52 countries are quantified.

  20. Risk evolution: how can changes in the built environment influence the potential loss of natural hazards?

    Directory of Open Access Journals (Sweden)

    B. Schwendtner

    2013-09-01

    Full Text Available Alpine areas often suffer significant loss and damage due to a range of natural processes such as landslides, debris flows, snow avalanches or floods. Sealing of the soil surface, settling in endangered areas and enhanced human intervention in the natural settings, as well as socio-economic changes, increase the risk and susceptibility of built environments to natural hazards and the costs of the consequences in a spatio-temporal context. The present study examines the loss estimation of a particular debris flow event for different points in time. The event occurred in August 1987, affected the municipality Martell in South Tyrol, Italy, and resulted in a total cost of € 25 million. The approach presented in this paper focuses on the changes of the land use and settlement expansion in the area since 1954 and attempts to assess the monetary impact of a similar event, which could have happened before (1954, 1985 or following the actual event (1992, 1999, 2006. The method applied is based on the use of a vulnerability curve which was developed for the specific area, based on the documentation of the damage of the 1987 event. Based on this curve, a loss estimation was carried out in order to visualise the risk evolution in a period of 52 yr (1954 to 2006. The results show a significant increase in the extent of the built environment (number, size and value of buildings which consequently reflect an increase of the potential overall loss through the years. The method can be used in order to assess the potential loss for future scenarios based on different spatial patterns of the built environment.

  1. Risk evolution: how can changes in the built environment influence the potential loss of natural hazards?

    Science.gov (United States)

    Schwendtner, B.; Papathoma-Köhle, M.; Glade, T.

    2013-09-01

    Alpine areas often suffer significant loss and damage due to a range of natural processes such as landslides, debris flows, snow avalanches or floods. Sealing of the soil surface, settling in endangered areas and enhanced human intervention in the natural settings, as well as socio-economic changes, increase the risk and susceptibility of built environments to natural hazards and the costs of the consequences in a spatio-temporal context. The present study examines the loss estimation of a particular debris flow event for different points in time. The event occurred in August 1987, affected the municipality Martell in South Tyrol, Italy, and resulted in a total cost of € 25 million. The approach presented in this paper focuses on the changes of the land use and settlement expansion in the area since 1954 and attempts to assess the monetary impact of a similar event, which could have happened before (1954, 1985) or following the actual event (1992, 1999, 2006). The method applied is based on the use of a vulnerability curve which was developed for the specific area, based on the documentation of the damage of the 1987 event. Based on this curve, a loss estimation was carried out in order to visualise the risk evolution in a period of 52 yr (1954 to 2006). The results show a significant increase in the extent of the built environment (number, size and value of buildings) which consequently reflect an increase of the potential overall loss through the years. The method can be used in order to assess the potential loss for future scenarios based on different spatial patterns of the built environment.

  2. Oxidative stress and the high altitude environment

    Directory of Open Access Journals (Sweden)

    Jakub Krzeszowiak

    2013-03-01

    Full Text Available In the recent years there has been considerable interest in mountain sports, including mountaineering, owing to the general availability of climbing clothing and equipment as well trainings and professional literature. This raised a new question for the environmental and mountain medicine: Is mountaineering harmful to health? Potential hazards include the conditions existing in the alpine environment, i.e. lower atmospheric pressure leading to the development of hypobaric hypoxia, extreme physical effort, increased UV radiation, lack of access to fresh food, and mental stress. A reasonable measure of harmfulness of these factors is to determine the increase in the level of oxidative stress. Alpine environment can stimulate the antioxidant enzyme system but under specific circumstances it may exceed its capabilities with simultaneous consumption of low-molecular antioxidants resulting in increased generation of reactive oxygen species (ROS. This situation is referred to as oxidative stress. Rapid and uncontrolled proliferation of reactive oxygen species leads to a number of adverse changes, resulting in the above-average damage to the lipid structures of cell membranes (peroxidation, proteins (denaturation, and nucleic acids. Such situation within the human body cannot take place without resultant systemic consequences. This explains the malaise of people returning from high altitude and a marked decrease in their physical fitness. In addition, a theory is put forward that the increase in the level of oxidative stress is one of the factors responsible for the onset of acute mountain sickness (AMS. However, such statement requires further investigation because the currently available literature is inconclusive. This article presents the causes and effects of development of oxidative stress in the high mountains.

  3. High Speed Gear Sized and Configured to Reduce Windage Loss

    Science.gov (United States)

    Kunz, Robert F. (Inventor); Medvitz, Richard B. (Inventor); Hill, Matthew John (Inventor)

    2013-01-01

    A gear and drive system utilizing the gear include teeth. Each of the teeth has a first side and a second side opposite the first side that extends from a body of the gear. For each tooth of the gear, a first extended portion is attached to the first side of the tooth to divert flow of fluid adjacent to the body of the gear to reduce windage losses that occur when the gear rotates. The gear may be utilized in drive systems that may have high rotational speeds, such as speeds where the tip velocities are greater than or equal to about 68 m/s. Some embodiments of the gear may also utilize teeth that also have second extended portions attached to the second sides of the teeth to divert flow of fluid adjacent to the body of the gear to reduce windage losses that occur when the gear rotates.

  4. Nitrogen footprints: Regional realities and options to reduce nitrogen loss to the environment.

    Science.gov (United States)

    Shibata, Hideaki; Galloway, James N; Leach, Allison M; Cattaneo, Lia R; Cattell Noll, Laura; Erisman, Jan Willem; Gu, Baojing; Liang, Xia; Hayashi, Kentaro; Ma, Lin; Dalgaard, Tommy; Graversgaard, Morten; Chen, Deli; Nansai, Keisuke; Shindo, Junko; Matsubae, Kazuyo; Oita, Azusa; Su, Ming-Chien; Mishima, Shin-Ichiro; Bleeker, Albert

    2017-03-01

    Nitrogen (N) management presents a sustainability dilemma: N is strongly linked to energy and food production, but excess reactive N causes environmental pollution. The N footprint is an indicator that quantifies reactive N losses to the environment from consumption and production of food and the use of energy. The average per capita N footprint (calculated using the N-Calculator methodology) of ten countries varies from 15 to 47 kg N capita-1 year-1. The major cause of the difference is the protein consumption rates and food production N losses. The food sector dominates all countries' N footprints. Global connections via trade significantly affect the N footprint in countries that rely on imported foods and feeds. The authors present N footprint reduction strategies (e.g., improve N use efficiency, increase N recycling, reduce food waste, shift dietary choices) and identify knowledge gaps (e.g., the N footprint from nonfood goods and soil N process).

  5. Siderophore production in high iron environments

    Science.gov (United States)

    Bennett, S. A.; Hoffman, C. L.; Moffett, J. W.; Edwards, K. J.

    2010-12-01

    Up until recently, the geochemical cycling of Fe in deep sea hydrothermal plumes has assumed to be inorganically dominated, resulting in quantitative precipitation of all hydrothermally sourced Fe to the seafloor. Recent detection of organic Fe binding ligands within both the dissolved and particulate phase (Bennett et al., 2008; Toner et al., 2009), suggests that hydrothermally sourced Fe may be important on a global scale (Tagliabue et al., 2010). The source of these organic ligands is currently unknown; hypotheses include the possible entrainment of organic carbon from the biologically rich diffuse flow areas, or in-situ production from microbial processes. However, the microbial production of organic ligands is only expected when Fe is a limited micronutrient, which is not the case in the hydrothermal environment. The importance of Fe cycling microorganisms within hydrothermal systems was previously overlooked due to the poor energetics with regards to Fe oxidation and reduction. But their recent detection within the hydrothermal system, both around low temperature Fe rich mineral deposits and within hydrothermal plumes (Edwards et al., 2004; Sylvan et al., In prep) suggests that they may have an important role in the hydrothermal Fe cycle, potentially resulting in an interplay between Fe and organic carbon. Within the laboratory, we have carried out experiments to investigate an Fe oxidizing bacteria in a variety of high Fe environments. We have detected both the production of siderophores and an increase in reduced Fe when the Fe oxidizing bacteria is exposed to both Fe(III) and Fe(II) rich minerals. The role of these microbes in the mineral dissolution of Fe sulfides along the seafloor and within the hydrothermal plume, may have important implications on the speciation of Fe and the role of siderophores in the marine environment. Bennett, S.A. et al. 2008. EPSL, 270: 157-167. Edwards, K.J. et al. 2004. Geomicrobiology Journal, 21: 393-404. Sylvan, J.B. et al

  6. Error Analysis of High Frequency Core Loss Measurement for Low-Permeability Low-Loss Magnetic Cores

    DEFF Research Database (Denmark)

    Niroumand, Farideh Javidi; Nymand, Morten

    2016-01-01

    in magnetic cores is B-H loop measurement where two windings are placed on the core under test. However, this method is highly vulnerable to phase shift error, especially for low-permeability, low-loss cores. Due to soft saturation and very low core loss, low-permeability low-loss magnetic cores are favorable...... in many of the high-efficiency high power-density power converters. Magnetic powder cores, among the low-permeability low-loss cores, are very attractive since they possess lower magnetic losses in compared to gapped ferrites. This paper presents an analytical study of the phase shift error in the core....... The analysis has been validated by experimental measurements for relatively low-loss magnetic cores with different permeability values....

  7. Effects of Wintering Environment and Parasite-Pathogen Interactions on Honey Bee Colony Loss in North Temperate Regions.

    Directory of Open Access Journals (Sweden)

    Suresh D Desai

    Full Text Available Extreme winter losses of honey bee colonies are a major threat to beekeeping but the combinations of factors underlying colony loss remain debatable. We monitored colonies in two environments (colonies wintered indoors or outdoors and characterized the effects of two parasitic mites, seven viruses, and Nosema on honey bee colony mortality and population loss over winter. Samples were collected from two locations within hives in fall, mid-winter and spring of 2009/2010. Although fall parasite and pathogen loads were similar in outdoor and indoor-wintered colonies, the outdoor-wintered colonies had greater relative reductions in bee population score over winter. Seasonal patterns in deformed wing virus (DWV, black queen cell virus (BQCV, and Nosema level also differed with the wintering environment. DWV and Nosema levels decreased over winter for indoor-wintered colonies but BQCV did not. Both BQCV and Nosema concentration increased over winter in outdoor-wintered colonies. The mean abundance of Varroa decreased and concentration of Sacbrood virus (SBV, Kashmir bee virus (KBV, and Chronic bee paralysis virus (CBPV increased over winter but seasonal patterns were not affected by wintering method. For most viruses, either entrance or brood area samples were reasonable predictors of colony virus load but there were significant season*sample location interactions for Nosema and BQCV, indicating that care must be taken when selecting samples from a single location. For Nosema spp., the fall entrance samples were better predictors of future infestation levels than were fall brood area samples. For indoor-wintered colonies, Israeli acute paralysis virus IAPV concentration was negatively correlated with spring population size. For outdoor-wintered hives, spring Varroa abundance and DWV concentration were positively correlated with bee loss and negatively correlated with spring population size. Multivariate analyses for fall collected samples indicated

  8. Iron loss in high-power arc steelmaking furnaces

    Directory of Open Access Journals (Sweden)

    V. P. Karasyov

    2016-07-01

    Full Text Available There is considered the power operating mode of a high-power arc steelmaking furnaces (ASMF in the period of the flat bath. It is revealed that electric energy is mainly spent for heating and overheating the foamed slag. Heat transferring from slag to metal is carried out by the convective agitation of the bath. For agitation there is used intensive purging of the bath with oxygen that causes increased iron losses with the running foamed slag. There are noted the negative points of working with the foamed slag. It is recommended to expand R&D in the field of optimizing the power operating mode of high-power ASMF.

  9. High Radiation Environment Nuclear Fragment Separator Magnet

    Energy Technology Data Exchange (ETDEWEB)

    Kahn, Stephen [Muons, Inc., Batavia, IL (United States); Gupta, Ramesh [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2016-01-31

    Superconducting coils wound with HTS conductor can be used in magnets located in a high radiation environment. NbTi and Nb3Sn superconductors must operate at 4.5 K or below where removal of heat is less efficient. The HTS conductor can carry significant current at higher temperatures where the Carnot efficiency is significantly more favorable and where the coolant heat capacity is much larger. Using the HTS conductor the magnet can be operated at 40 K. This project examines the use of HTS conductor for the Michigan State University Facility For Rare Isotope Beams (FRIB) fragment separator dipole magnet which bends the beam by 30° and is located in a high radiation region that will not be easily accessible. Two of these magnets are needed to select the chosen isotope. There are a number of technical challenges to be addressed in the design of this magnet. The separator dipole is 2 m long and subtends a large angle. The magnet should keep a constant transverse field profile along its beam reference path. Winding coils with a curved inner segment is difficult as the conductor will tend to unwind during the process. In the Phase I project two approaches to winding the conductor were examined. The first was to wind the coils with curved sections on the inner and outer segments with the inner segment wound with negative curvature. The alternate approach was to use a straight segment on the inner segment to avoid negative curvature. In Phase I coils with a limited number of turns were successfully wound and tested at 77 K for both coil configurations. The Phase II program concentrated on the design, coil winding procedures, structural analysis, prototyping and testing of an HTS curved dipole coil at 40 K with a heat load representative of the radiation environment. One of the key criteria of the design of this magnet is to avoid the use of organic materials that would degrade rapidly in radiation. The Lorentz forces expected from the coils interacting with the

  10. Beam Loss Calibration Studies for High Energy Proton Accelerators

    CERN Document Server

    Stockner, M

    2007-01-01

    CERN's Large Hadron Collider (LHC) is a proton collider with injection energy of 450 GeV and collision energy of 7 TeV. Superconducting magnets keep the particles circulating in two counter rotating beams, which cross each other at the Interaction Points (IP). Those complex magnets have been designed to contain both beams in one yoke within a cryostat. An unprecedented amount of energy will be stored in the circulating beams and in the magnet system. The LHC outperforms other existing accelerators in its maximum beam energy by a factor of 7 and in its beam intensity by a factor of 23. Even a loss of a small fraction of the beam particles may cause the transition from the superconducting to the normal conducting state of the coil or cause physical damage to machine components. The unique combination of these extreme beam parameters and the highly advanced superconducting technology has the consequence that the LHC needs a more efficient beam cleaning and beam loss measurement system than previous accelerators....

  11. NOvel Refractory Materials for High Alkali, High Temperature Environments

    Energy Technology Data Exchange (ETDEWEB)

    Hemrick, J.G.; Griffin, R. (MINTEQ International, Inc.)

    2011-08-30

    Refractory materials can be limited in their application by many factors including chemical reactions between the service environment and the refractory material, mechanical degradation of the refractory material by the service environment, temperature limitations on the use of a particular refractory material, and the inability to install or repair the refractory material in a cost effective manner or while the vessel was in service. The objective of this project was to address the need for new innovative refractory compositions by developing a family of novel MgO-Al2O3 spinel or other similar magnesia/alumina containing unshaped refractory composition (castables, gunnables, shotcretes, etc) utilizing new aggregate materials, bond systems, protective coatings, and phase formation techniques (in-situ phase formation, altered conversion temperatures, accelerated reactions, etc). This family of refractory compositions would then be tailored for use in high-temperature, highalkaline industrial environments like those found in the aluminum, chemical, forest products, glass, and steel industries. A research team was formed to carry out the proposed work led by Oak Ridge National Laboratory (ORNL) and was comprised of the academic institution Missouri University of Science and Technology (MS&T), and the industrial company MINTEQ International, Inc. (MINTEQ), along with representatives from the aluminum, chemical, glass, and forest products industries. The two goals of this project were to produce novel refractory compositions which will allow for improved energy efficiency and to develop new refractory application techniques which would improve the speed of installation. Also methods of hot installation were sought which would allow for hot repairs and on-line maintenance leading to reduced process downtimes and eliminating the need to cool and reheat process vessels.

  12. Unexpected high losses of Anopheles gambiae larvae due to rainfall.

    Directory of Open Access Journals (Sweden)

    Krijn P Paaijmans

    Full Text Available BACKGROUND: Immature stages of the malaria mosquito Anopheles gambiae experience high mortality, but its cause is poorly understood. Here we study the impact of rainfall, one of the abiotic factors to which the immatures are frequently exposed, on their mortality. METHODOLOGY/PRINCIPAL FINDINGS: We show that rainfall significantly affected larval mosquitoes by flushing them out of their aquatic habitat and killing them. Outdoor experiments under natural conditions in Kenya revealed that the additional nightly loss of larvae caused by rainfall was on average 17.5% for the youngest (L1 larvae and 4.8% for the oldest (L4 larvae; an additional 10.5% (increase from 0.9 to 11.4% of the L1 larvae and 3.3% (from 0.1 to 3.4% of the L4 larvae were flushed away and larval mortality increased by 6.9% (from 4.6 to 11.5% and 1.5% (from 4.1 to 5.6% for L1 and L4 larvae, respectively, compared to nights without rain. On rainy nights, 1.3% and 0.7% of L1 and L4 larvae, respectively, were lost due to ejection from the breeding site. CONCLUSIONS/SIGNIFICANCE: This study demonstrates that immature populations of malaria mosquitoes suffer high losses during rainfall events. As these populations are likely to experience several rain showers during their lifespan, rainfall will have a profound effect on the productivity of mosquito breeding sites and, as a result, on the transmission of malaria. These findings are discussed in the light of malaria risk and changing rainfall patterns in response to climate change.

  13. Occupational hearing loss: tonal audiometry X high frequencies audiometry

    Directory of Open Access Journals (Sweden)

    Lauris, José Roberto Pereira

    2009-09-01

    Full Text Available Introduction: Studies on the occupational exposure show that noise has been reaching a large part of the working population around the world, and NIHL (noise-induced hearing loss is the second most frequent disease of the hearing system. Objective: To review the audiometry results of employees at the campus of the University of São Paulo, Bauru. Method: 40 audiometry results were analyzed between 2007 and 2008, whose ages comprised between 32 and 59 years, of both sexes and several professions: gardeners, maintenance technicians, drivers etc. The participants were divided into 2 groups: those with tonal thresholds within acceptable thresholds and those who presented auditory thresholds alterations, that is tonal thresholds below 25 dB (NA in any frequency (Administrative Rule no. 19 of the Ministry of Labor 1998. In addition to the Conventional Audiologic Evaluation (250Hz to 8.000Hz we also carried out High Frequencies Audiometry (9000Hz, 10000Hz, 11200Hz, 12500Hz, 14000Hz and 16000Hz. Results: According to the classification proposed by FIORINI (1994, 25.0% (N=10 they presented with NIHL suggestive audiometric configurations. The results of high frequencies Audiometry confirmed worse thresholds than those obtained in the conventional audiometry in the 2 groups evaluated. Conclusion: The use of high frequencies audiometry proved to be an important register as a hearing alteration early detection method.

  14. Sound transmission loss of windows on high speed trains

    Science.gov (United States)

    Zhang, Yumei; Xiao, Xinbiao; Thompson, David; Squicciarini, Giacomo; Wen, Zefeng; Li, Zhihui; Wu, Yue

    2016-09-01

    The window is one of the main components of the high speed train car body structure through which noise can be transmitted. To study the windows’ acoustic properties, the vibration of one window of a high speed train has been measured for a running speed of 250 km/h. The corresponding interior noise and the noise in the wheel-rail area have been measured simultaneously. The experimental results show that the window vibration velocity has a similar spectral shape to the interior noise. Interior noise source identification further indicates that the window makes a contribution to the interior noise. Improvement of the window's Sound Transmission Loss (STL) can reduce the interior noise from this transmission path. An STL model of the window is built based on wave propagation and modal superposition methods. From the theoretical results, the window's STL property is studied and several factors affecting it are investigated, which provide indications for future low noise design of high speed train windows.

  15. Electron-induced hydrogen loss in uracil in a water cluster environment

    Energy Technology Data Exchange (ETDEWEB)

    Smyth, M.; Kohanoff, J. [Atomistic Simulation Centre, Queen' s University Belfast, Belfast BT7 1NN, Northern Ireland (United Kingdom); Fabrikant, I. I., E-mail: ifabrikant1@unl.edu [Department of Physics and Astronomy, University of Nebraska, Lincoln, Nebraska 68588, USA and Department of Physical Sciences, The Open University, Walton Hall, Milton Keynes MK7 6AA (United Kingdom)

    2014-05-14

    Low-energy electron-impact hydrogen loss due to dissociative electron attachment (DEA) to the uracil and thymine molecules in a water cluster environment is investigated theoretically. Only the A{sup ′}-resonance contribution, describing the near-threshold behavior of DEA, is incorporated. Calculations are based on the nonlocal complex potential theory and the multiple scattering theory, and are performed for a model target with basic properties of uracil and thymine, surrounded by five water molecules. The DEA cross section is strongly enhanced when the attaching molecule is embedded in a water cluster. This growth is due to two effects: the increase of the resonance lifetime and the negative shift in the resonance position due to interaction of the intermediate negative ion with the surrounding water molecules. A similar effect was earlier found in DEA to chlorofluorocarbons.

  16. Study The Properties and Weight Loss Degradation of The Blend LDPE/Cellulose in Soil Environment

    Directory of Open Access Journals (Sweden)

    Zuhair Jabbar Abdul Ameer

    2017-05-01

    Full Text Available Wider applications of polyethylene (PE in packaging and agriculture have raised serious issue of waste disposal and pollution. Therefore, it is necessary to raise its biodegradability by additives.In this study, we will add cellulose to low density polyethylene to prepare polymer blend have ability to degradation in soil environment.The samples were prepared by using twin screw extruder.LDPE and CELL have been mixing with different weight proportions, and studied their properties in order to determine its compliance with the required specifications to be able to be used biodegradable polymers. To improve the viability of decomposition PEG has been added to the resulting blend. Several tests were applied to identify those properties such as tensile,hardness, density and creep test. FTIR, digital microscope and SEM test acheved in order to determine the miscibility and blend morphology befor and after degradation.The results show that,the blend weight loss increase with increasing CELL percent.

  17. Electron-induced hydrogen loss in uracil in a water cluster environment.

    Science.gov (United States)

    Smyth, M; Kohanoff, J; Fabrikant, I I

    2014-05-14

    Low-energy electron-impact hydrogen loss due to dissociative electron attachment (DEA) to the uracil and thymine molecules in a water cluster environment is investigated theoretically. Only the A(')-resonance contribution, describing the near-threshold behavior of DEA, is incorporated. Calculations are based on the nonlocal complex potential theory and the multiple scattering theory, and are performed for a model target with basic properties of uracil and thymine, surrounded by five water molecules. The DEA cross section is strongly enhanced when the attaching molecule is embedded in a water cluster. This growth is due to two effects: the increase of the resonance lifetime and the negative shift in the resonance position due to interaction of the intermediate negative ion with the surrounding water molecules. A similar effect was earlier found in DEA to chlorofluorocarbons.

  18. Energy metabolism and the high-altitude environment.

    Science.gov (United States)

    Murray, Andrew J

    2016-01-01

    At high altitude the barometric pressure falls, challenging oxygen delivery to the tissues. Thus, whilst hypoxia is not the only physiological stress encountered at high altitude, low arterial P(O2) is a sustained feature, even after allowing adequate time for acclimatization. Cardiac and skeletal muscle energy metabolism is altered in subjects at, or returning from, high altitude. In the heart, energetic reserve falls, as indicated by lower phosphocreatine-to-ATP ratios. The underlying mechanism is unknown, but in the hypoxic rat heart fatty acid oxidation and respiratory capacity are decreased, whilst pyruvate oxidation is also lower after sustained hypoxic exposure. In skeletal muscle, there is not a consensus. With prolonged exposure to extreme high altitude (>5500 m) a loss of muscle mitochondrial density is seen, but this was not observed in a simulated ascent of Everest in hypobaric chambers. At more moderate high altitude, decreased respiratory capacity may occur without changes in mitochondrial volume density, and fat oxidation may be downregulated, although this is not seen in all studies. The underlying mechanisms, including the possible role of hypoxia-signalling pathways, remain to be resolved, particularly in light of confounding factors in the high-altitude environment. In high-altitude-adapted Tibetan natives, however, there is evidence of natural selection centred around the hypoxia-inducible factor pathway, and metabolic features in this population (e.g. low cardiac phosphocreatine-to-ATP ratios, increased cardiac glucose uptake and lower muscle mitochondrial densities) share similarities with those in acclimatized lowlanders, supporting a possible role for the hypoxia-inducible factor pathway in the metabolic response of cardiac and skeletal muscle energy metabolism to high altitude. © 2015 The Authors. Experimental Physiology © 2015 The Physiological Society.

  19. Diamond based detectors for high temperature, high radiation environments

    Science.gov (United States)

    Metcalfe, A.; Fern, G. R.; Hobson, P. R.; Smith, D. R.; Lefeuvre, G.; Saenger, R.

    2017-01-01

    Single crystal CVD diamond has many desirable properties as a radiation detector; exceptional radiation hardness and physical hardness, chemical inertness, low Z (close to human tissue, good for dosimetry and transmission mode applications), wide bandgap (high temperature operation with low noise and solar blind), an intrinsic pathway to fast neutron detection through the 12C(n,α)9Be reaction. This combination of radiation hardness, temperature tolerance and ability to detect mixed radiation types with a single sensor makes diamond particularly attractive as a detector material for harsh environments such as nuclear power station monitoring (fission and fusion) and oil well logging. Effective exploitation of these properties requires the development of a metallisation scheme to give contacts that remain stable over extended periods at elevated temperatures (up to 250°C in this instance). Due to the cost of the primary detector material, computational modelling is essential to best utilise the available processing methods for optimising sensor response through geometry and conversion media configurations and to fully interpret experimental data. Monte Carlo simulations of our diamond based sensor have been developed, using MCNP6 and FLUKA2011, assessing the sensor performance in terms of spectral response and overall efficiency as a function of the detector and converter geometry. Sensors with varying metallisation schemes for high temperature operation have been fabricated at Brunel University London and by Micron Semiconductor Limited. These sensors have been tested under a varied set of conditions including irradiation with fast neutrons and alpha particles at high temperatures. The presented study indicates that viable metallisation schemes for high temperature contacts have been successfully developed and the modelling results, supported by preliminary experimental data from partners, indicate that the simulations provide a reasonable representation of

  20. Estimation of Transformer Parameters and Loss Analysis for High Voltage Capacitor Charging Application

    DEFF Research Database (Denmark)

    Thummala, Prasanth; Schneider, Henrik; Ouyang, Ziwei

    2013-01-01

    In a bi-directional DC-DC converter for capacitive charging application, the losses associated with the transformer makes it a critical component. In order to calculate the transformer losses, its parameters such as AC resistance, leakage inductance and self capacitance of the high voltage (HV......) winding has to be estimated accurately. This paper analyzes the following losses of bi-directional flyback converter namely switching loss, conduction loss, gate drive loss, transformer core loss, and snubber loss, etc. Iterative analysis of transformer parameters viz., AC resistance, leakage inductance...

  1. High-elevation mass loss of Greenland increasing

    DEFF Research Database (Denmark)

    Andersen, M. L.; Andersen, S. B.; Ahlstrøm, A. P.

    The Greenland Ice Sheet is losing mass at an accelerated pace. Presently, the mass loss is assumed to be distributed approximately equally between loss in the form of surface melt (surface mass balance, SMB) and solid ice discharge (iceberg calving, D) along the margins. As part of the PROMICE...

  2. Environment

    DEFF Research Database (Denmark)

    Valentini, Chiara

    2017-01-01

    The term environment refers to the internal and external context in which organizations operate. For some scholars, environment is defined as an arrangement of political, economic, social and cultural factors existing in a given context that have an impact on organizational processes and structures....... For others, environment is a generic term describing a large variety of stakeholders and how these interact and act upon organizations. Organizations and their environment are mutually interdependent and organizational communications are highly affected by the environment. This entry examines the origin...... and development of organization-environment interdependence, the nature of the concept of environment and its relevance for communication scholarships and activities....

  3. NOVEL REFRACTORY MATERIALS FOR HIGH ALKALI, HIGH TEMPERATURE ENVIRONMENTS

    Energy Technology Data Exchange (ETDEWEB)

    Hemrick, James Gordon [ORNL; Smith, Jeffrey D [ORNL; O' Hara, Kelley [University of Missouri, Rolla; Rodrigues-Schroer, Angela [Minteq International, Inc.; Colavito, [Minteq International, Inc.

    2012-08-01

    A project was led by Oak Ridge National Laboratory (ORNL) in collaboration with a research team comprised of the academic institution Missouri University of Science and Technology (MS&T), and the industrial company MINTEQ International, Inc. (MINTEQ), along with representatives from the aluminum, chemical, glass, and forest products industries. The project was to address the need for new innovative refractory compositions by developing a family of novel MgO-Al 2O3, MgAl2O4, or other similar spinel structured or alumina-based unshaped refractory compositions (castables, gunnables, shotcretes, etc.) utilizing new aggregate materials, bond systems, protective coatings, and phase formation techniques (in-situ phase formation, altered conversion temperatures, accelerated reactions, etc). This family of refractory compositions would then be tailored for use in high-temperature, high-alkaline industrial environments like those found in the aluminum, chemical, forest products, glass, and steel industries. Both practical refractory development experience and computer modeling techniques were used to aid in the design of this new family of materials. The newly developed materials were expected to offer alternative material choices for high-temperature, high-alkali environments that were capable of operating at higher temperatures (goal of increasing operating temperature by 100-200oC depending on process) or for longer periods of time (goal of twice the life span of current materials or next process determined service increment). This would lead to less process down time, greater energy efficiency for associated manufacturing processes (more heat kept in process), and materials that could be installed/repaired in a more efficient manner. The overall project goal was a 5% improvement in energy efficiency (brought about through a 20% improvement in thermal efficiency) resulting in a savings of 3.7 TBtu/yr (7.2 billion ft3 natural gas) by the year 2030. Additionally, new

  4. High-tech solutions for the environment

    CERN Multimedia

    Gabrielle Thomas

    2013-01-01

    Four solar-powered compactor dustbins have recently been installed at various locations around the Meyrin site. These compact systems fitted with photovoltaic panels compress waste; their increased capacity compared to a standard dustbin reduces the number of collections and the associated CO2 emissions.   Four strange "machines" have recently appeared on the CERN site. Made by the company Big Belly, these intelligent solar-powered mini-compactors fitted with the latest energy-saving technology are perfectly aligned with the Laboratory's policy of minimising the impact of its activities on the environment. With their ability to hold up to four times more waste than the average bin, they need to be emptied less frequently, significantly reducing the CO2 emissions associated with collection and transport. What's more, the integrated software monitors the fill level of each bin in real time and sends an e-mail or text when it needs emptying, thus optimising coll...

  5. Ain’t no mountain high enough? Setting high weight loss goals predict effort and short-term weight loss

    NARCIS (Netherlands)

    de Vet, E.; Nelissen, R.M.A.; Zeelenberg, M.; de Ridder, D.T.D.

    2013-01-01

    Although psychological theories outline that it might be beneficial to set more challenging goals, people attempting to lose weight are generally recommended to set modest weight loss goals. The present study explores whether the amount of weight loss individuals strive for is associated with more

  6. Ain’t no mountain high enough? Setting high weight loss goals predicts effort and short-term weight loss

    NARCIS (Netherlands)

    Vet, de E.; Nelissen, R.M.A.; Zeelenberg, M.; Ridder, de D.T.D.

    2013-01-01

    Although psychological theories outline that it might be beneficial to set more challenging goals, people attempting to lose weight are generally recommended to set modest weight loss goals. The present study explores whether the amount of weight loss individuals strive for is associated with more

  7. Injury Signals Cooperate with Nf1 Loss to Relieve the Tumor-Suppressive Environment of Adult Peripheral Nerve

    Directory of Open Access Journals (Sweden)

    Sara Ribeiro

    2013-10-01

    Full Text Available Schwann cells are highly plastic cells that dedifferentiate to a progenitor-like state following injury. However, deregulation of this plasticity, may be involved in the formation of neurofibromas, mixed-cell tumors of Schwann cell (SC origin that arise upon loss of NF1. Here, we show that adult myelinating SCs (mSCs are refractory to Nf1 loss. However, in the context of injury, Nf1-deficient cells display opposing behaviors along the wounded nerve; distal to the injury, Nf1−/− mSCs redifferentiate normally, whereas at the wound site Nf1−/− mSCs give rise to neurofibromas in both Nf1+/+ and Nf1+/− backgrounds. Tracing experiments showed that distinct cell types within the tumor derive from Nf1-deficient SCs. This model of neurofibroma formation demonstrates that neurofibromas can originate from adult SCs and that the nerve environment can switch from tumor suppressive to tumor promoting at a site of injury. These findings have implications for both the characterization and treatment of neurofibromas.

  8. Financial system loss as an example of high consequence, high frequency events

    Energy Technology Data Exchange (ETDEWEB)

    McGovern, D.E.

    1996-07-01

    Much work has been devoted to high consequence events with low frequency of occurrence. Characteristic of these events are bridge failure (such as that of the Tacoma Narrows), building failure (such as the collapse of a walkway at a Kansas City hotel), or compromise of a major chemical containment system (such as at Bhopal, India). Such events, although rare, have an extreme personal, societal, and financial impact. An interesting variation is demonstrated by financial losses due to fraud and abuse in the money management system. The impact can be huge, entailing very high aggregate costs, but these are a result of the contribution of many small attacks and not the result of a single (or few) massive events. Public awareness is raised through publicized events such as the junk bond fraud perpetrated by Milikin or gross mismanagement in the failure of the Barings Bank through unsupervised trading activities by Leeson in Singapore. These event,s although seemingly large (financial losses may be on the order of several billion dollars), are but small contributors to the estimated $114 billion loss to all types of financial fraud in 1993. This paper explores the magnitude of financial system losses and identifies new areas for analysis of high consequence events including the potential effect of malevolent intent.

  9. RELAXATIONS LOSSES IN POLYETHYLENE INSULATION OF COAXIAL CABLE STRUCTURE DURING AGING IN HIGH HUMIDITY CONDITIONS

    Directory of Open Access Journals (Sweden)

    G.V. Bezprozvannych

    2016-05-01

    Full Text Available Introduction. The presence of free moisture in power cables leading to the formation of tree structures - water treeing, which originate in the amorphous phase polyethylene and are a major cause of degradation of the polymer insulation. They represent the damage of the polymer size from several microns to 1 mm, developing technology for insulation defects under the combined action of the electric field and the moisture diffusing from the environment. Water treeing destroys the polymer chain, resulting in the formation of microcavities filled with moisture. The dynamics of water treeing and subtle properties largely depend on the composition, morphology of the polymer insulation, chemical nature of the defect, in which they originate. Due to the force of gravity in the water formed typical only for her region with locally ordered structure - clusters, which cause loss of relaxation. Purpose. Features presence of relaxation losses in high-frequency range in polyethylene insulation during aging in high humidity conditions of samples power and RF cables. Methodology. Samples of the power cable for the voltage of 35 kV with a cross-linked polyethylene insulation radial water-blocking protection from moisture and radio-frequency coaxial cable with thermoplastic insulation for 1440 hours in a humidity of 100%. The dielectric loss tangent measured resonance method before and after aging. Originality. Experimentally found evidence of the existence in the polymer cable insulation free water in the form of areas with locally ordered structure - clusters. It is found that the solid polyethylene insulation in the frequency dependence of dielectric loss tangent maximum relaxation shown one at 10 MHz in the initial state, and there are two additional frequency range 500 kHz - 5 MHz after moistening. For cross-linked polyethylene insulation characteristic of large width Δf of the frequency spectrum in which the observed relaxation losses. It is obvious that

  10. High temperature oxidation in boiler environment of chromized steel

    Science.gov (United States)

    Alia, F. F.; Kurniawan, T.; Asmara, Y. P.; Ani, M. H. B.; Nandiyanto, A. B. D.

    2017-10-01

    The demand for increasing efficiency has led to the development and construction of higher operating temperature power plant. This condition may lead to more severe thickness losses in boiler tubes due to excessive corrosion process. Hence, the research to improve the corrosion resistance of the current operated material is needed so that it can be applied for higher temperature application. In this research, the effect of chromizing process on the oxidation behaviour of T91 steel was investigated under steam condition. In order to deposit chromium, mixture of chromium (Cr) powder as master alloy, halide salt (NH4Cl) powder as activator and alumina (Al2O3) powder as inert filler were inserted into alumina retort together with the steel sample and heated inside furnace at 1050°C for ten hours under argon gas environment. Furthermore, for the oxidation process, steels were exposed at 700°C at different oxidation time (6h-24h) under steam condition. From FESEM/EDX analysis, it was found that oxidation rate of pack cemented steel was lower than the un-packed steel. These results show that Cr from chromizing process was able to become reservoir for the formation of Cr2O3 in high temperature steam oxidation, and its existence can be used for a longer oxidation time.

  11. Investigation of Long-Term Prestress Losses in Pretensioned High Performance Concrete Girders

    OpenAIRE

    Cousins, Thomas E.

    2005-01-01

    Effective determination of long-term prestress losses is important in the design of prestressed concrete bridges. Over-predicting prestress losses results in an overly conservative design for service load stresses, and under-predicting prestress losses, can result in cracking at service loads. Creep and shrinkage produce the most significant time-dependent effect on prestress losses, and research has shown that high performance and high strength concretes (HPC and HSC) exhibit less creep and ...

  12. Track reconstruction in CMS high luminosity environment

    CERN Document Server

    Goetzmann, Christophe

    2014-01-01

    The CMS tracker is the largest silicon detector ever built, covering 200 square meters and providing an average of 14 high-precision measurements per track. Tracking is essential for the reconstruction of objects like jets, muons, electrons and tau leptons starting from the raw data from the silicon pixel and strip detectors. Track reconstruction is widely used also at trigger level as it improves objects tagging and resolution.The CMS tracking code is organized in several levels, known as iterative steps, each optimized to reconstruct a class of particle trajectories, as the ones of particles originating from the primary vertex or displaced tracks from particles resulting from secondary vertices. Each iterative step consists of seeding, pattern recognition and fitting by a kalman filter, and a final filtering and cleaning. Each subsequent step works on hits not yet associated to a reconstructed particle trajectory.The CMS tracking code is continuously evolving to make the reconstruction computing load compat...

  13. Track reconstruction in CMS high luminosity environment

    CERN Document Server

    AUTHOR|(CDS)2067159

    2016-01-01

    The CMS tracker is the largest silicon detector ever built, covering 200 square meters and providing an average of 14 high-precision measurements per track. Tracking is essential for the reconstruction of objects like jets, muons, electrons and tau leptons starting from the raw data from the silicon pixel and strip detectors. Track reconstruction is widely used also at trigger level as it improves objects tagging and resolution.The CMS tracking code is organized in several levels, known as iterative steps, each optimized to reconstruct a class of particle trajectories, as the ones of particles originating from the primary vertex or displaced tracks from particles resulting from secondary vertices. Each iterative step consists of seeding, pattern recognition and fitting by a kalman filter, and a final filtering and cleaning. Each subsequent step works on hits not yet associated to a reconstructed particle trajectory.The CMS tracking code is continuously evolving to make the reconstruction computing load compat...

  14. Continuous high PRF waveforms for challenging environments

    Science.gov (United States)

    Jaroszewski, Steven; Corbeil, Allan; Ryland, Robert; Sobota, David

    2017-05-01

    Current airborne radar systems segment the available time-on-target during each beam dwell into multiple Coherent Processing Intervals (CPIs) in order to eliminate range eclipsing, solve for unambiguous range, and increase the detection performance against larger Radar Cross Section (RCS) targets. As a consequence, these radars do not realize the full Signal-to-Noise Ratio (SNR) increase and detection performance improvement that is possible. Continuous High Pulse Repetition Frequency (HPRF) waveforms and processing enables the coherent integration of all available radar data over the full time-on-target. This can greatly increase the SNR for air targets at long range and/or with weak radar returns and significantly improve the detection performance against such targets. TSC worked with its partner KeyW to implement a Continuous HPRF waveform in their Sahara radar testbed and obtained measured radar data on both a ground vehicle target and an airborne target of opportunity. This experimental data was processed by TSC to validate the expected benefits of Continuous HPRF waveforms.

  15. Study Progress of Physiological Responses in High Temperature Environment

    Science.gov (United States)

    Li, K.; Zheng, G. Z.; Bu, W. T.; Wang, Y. J.; Lu, Y. Z.

    2017-10-01

    Certain workers are exposed to high temperatures for a long time. Heat stress will result in a series of physiological responses, and cause adverse effects on the health and safety of workers. This paper summarizes the physiological changes of cardiovascular system, core temperature, skin temperature, water-electrolyte metabolism, alimentary system, neuroendocrine system, reaction time and thermal fatigue in high temperature environments. It can provide a theoretical guidance for labor safety in high temperature environment.

  16. Occupational hearing loss: tonal audiometry X high frequencies audiometry

    OpenAIRE

    Lauris, José Roberto Pereira; Basso, Talita Costa; Marinelli, Érica Juliana Innocenti; Otubo, Karina Aki; Lopes, Andréa Cintra

    2009-01-01

    Introduction: Studies on the occupational exposure show that noise has been reaching a large part of the working population around the world, and NIHL (noise-induced hearing loss) is the second most frequent disease of the hearing system. Objective: To review the audiometry results of employees at the campus of the University of São Paulo, Bauru. Method: 40 audiometry results were analyzed between 2007 and 2008, whose ages comprised between 32 and 59 years, of both sexes and several professio...

  17. Frequency loss induced quench protection system for high temperature superconductors

    Science.gov (United States)

    Ijagbemi, K.; Noyes, P.; Stiers, E.; Pamidi, S.

    2017-12-01

    A novel circuit design for Frequency Loss Induced Quench (FLIQ) protection system for safely driving REBCO coated conductor superconducting coils to quench is reported. The details of the H-bridge circuit design with Insulated Gate Bipolar Transistor (IGBT)s and the various elements used to build a prototype are reported. The results of a successful test of the circuit conducted to demonstrate the validity of the circuit design is presented.

  18. Quantifying Stellar Mass Loss with High Angular Resolution Imaging

    Science.gov (United States)

    2009-02-19

    material – via massive winds, planetary nebulae and supernova explosions – seeding the interstellar medium with heavier elements. Subsequent...loss and mass transfer, which means that their component stars have outer atmospheres which may be inconsistent with their interiors for a given age...by their status as type II supernova progenitors and their potential as independent distance indicators via the wind momentum-luminosity relationship

  19. Comparison of High-Performance Fiber Materials Properties in Simulated and Actual Space Environments

    Science.gov (United States)

    Finckernor, M. M.

    2017-01-01

    A variety of high-performance fibers, including Kevlar, Nomex, Vectran, and Spectra, have been tested for durability in the space environment, mostly the low Earth orbital environment. These materials have been tested in yarn, tether/cable, and fabric forms. Some material samples were tested in a simulated space environment, such as the Atomic Oxygen Beam Facility and solar simulators in the laboratory. Other samples were flown on the International Space Station as part of the Materials on International Space Station Experiment. Mass loss due to atomic oxygen erosion and optical property changes due to ultraviolet radiation degradation are given. Tensile test results are also presented, including where moisture loss in a vacuum had an impact on tensile strength.

  20. Science Laboratory Classroom Environments in Korean High Schools

    Science.gov (United States)

    Fraser, Barry J.; Lee, Sunny S. U.

    2009-01-01

    In order to investigate the learning environment of senior high school science laboratory classrooms in Korea, the Science Laboratory Environment Inventory (SLEI) was translated into Korean and administered to 439 students (99 science-independent stream students, 195 science-oriented stream students and 145 humanities stream students). Data…

  1. Thermal Loss of High-Q Antennas in Time Domain vs. Frequency Domain Solver

    DEFF Research Database (Denmark)

    Bahramzy, Pevand; Pedersen, Gert Frølund

    2014-01-01

    High-Q structures pose great challenges to their loss simulations in Time Domain Solvers (TDS). Therefore, in this work the thermal loss of high-Q antennas is calculated both in TDS and Frequency Domain Solver (FDS), which are then compared with each other and with the actual measurements....... The thermal loss calculation in FDS is shown to be more accurate for high-Q antennas....

  2. Optical loss reduction in high-index-contrast chalcogenide glass waveguides via thermal reflow.

    Science.gov (United States)

    Hu, Juejun; Feng, Ning-Ning; Carlie, Nathan; Petit, Laeticia; Agarwal, Anu; Richardson, Kathleen; Kimerling, Lionel

    2010-01-18

    A thermal reflow technique is applied to high-index-contrast, sub-micron waveguides in As(2)S(3) chalcogenide glass to reduce the sidewall roughness and associated optical scattering loss. We show that the reflow process effectively decreases sidewall roughness of chalcogenide glass waveguides. A kinetic model is presented to quantitatively explain the sidewall roughness evolution during thermal reflow. Further, we develop a technique to calculate waveguide optical loss using the roughness evolution model, and predict the ultimate low loss limit in reflowed high-index-contrast glass waveguides. Up to 50% optical loss reduction after reflow treatment is experimentally observed, and the practical loss limiting factors are discussed.

  3. Diabetic retinopathy: loss of neuroretinal adaptation to the diabetic metabolic environment

    Science.gov (United States)

    Abcouwer, Steven F.; Gardner, Thomas W.

    2014-01-01

    Diabetic retinopathy (DR) impairs vision of patients with type 1 and type 2 diabetes, associated with vascular dysfunction and occlusion, retinal edema, hemorrhage, and inappropriate growth of new blood vessels. The recent success of biologic treatments targeting vascular endothelial growth factor (VEGF) demonstrates that treating the vascular aspects in the later stages of the disease can preserve vision in many patients. It would also be highly desirable to prevent the onset of the disease or arrest its progression at a stage preceding the appearance of overt microvascular pathologies. The progression of DR is not necessarily linear but may follow a series of steps that evolve over the course of multiple years. Abundant data suggest that diabetes affects the entire neurovascular unit of the retina, with an early loss of neurovascular coupling, gradual neurodegeneration, gliosis, and neuroinflammation before observable vascular pathologies. In this article, we consider the pathology of diabetic retinopathy from the point of view that diabetes causes measurable dysfunctions in the complex integral network of cell types that produce and maintain human vision. PMID:24673341

  4. Comparison of sweat loss estimates for women during prolonged high-intensity running.

    Science.gov (United States)

    Cheuvront, Samuel N; Haymes, Emily M; Sawka, Michael N

    2002-08-01

    This study evaluated the error produced by four commonly used field estimates and two prediction equations of total body sweat loss. Eight women distance runners were studied during a 30-km treadmill run (approximately 70% .VO(2max)) in a warm (30 degrees C T(db)) and a cool (14 degrees C T(db)) environment. Total sweat loss (TSL) was determined from changes in body mass corrected for fluid intake (FI), urine losses (UL), clothing (trapped sweat, TS), CO(2)-O(2) exchange (metabolic mass loss, MML), and respiratory water loss (RWL). TSL was compared with four estimates of sweat losses (often employed in the field) from body mass changes corrected for: a) FI only (F-1); b) FI and TS (F-2); c) FI and UL (F-3); or d) FI, TS, and UL (F-4). Two prediction equations were used also for comparison to TSL values. In the warm environment, F-1, F-3, and F-4 accurately estimated (0.2-6.9%; P > 0.05) TSL, whereas F-2 produced a large error (15.3%; P equations markedly underestimated (20-22%) TSL in the warm environment and underestimated (41%) or overestimated (20%) TSL in the cool environment. TSL can be accurately estimated from changes in body mass using F-1, F-3, or F-4 methods in hot environments; however, none of the methods accurately estimated actual TSL values in a cool environment. Neither prediction equation provided accurate estimates of TSL in warm or cool conditions for women runners. These results illustrate the difficulty of accurately estimating and predicting sweat losses in the field.

  5. The interaction of spacecraft high voltage power systems with the space plasma environment

    Science.gov (United States)

    Domitz, S.; Grier, N. T.

    1974-01-01

    Research work has shown that the interaction of a spacecraft and its high voltage power systems with the space plasma environment can result in harmful power loss and damage to insulators and metal surfaces. Insulator and solar panel tests were performed and flight tests are planned. High voltage power processing equipment was shown to be affected by power loss, and by transients due to plasma interactions. Power loss was determined to be roughly proportional to the square of the voltage and increases approximately as the square root of the area. Kapton, Teflon, and glass were found to be satisfactory insulating materials and it is concluded that for large space power stations should consider the effect of large pinhole currents.

  6. Degradation of Solar Array Components in a Combined UV/VUV High Temperature Test Environment

    Directory of Open Access Journals (Sweden)

    Nömayr Christel

    2017-01-01

    A design verification test under UV/VUV conditions of sun exposed materials and technologies on component level is presented which forms part of the overall verification and qualification of the solar array design of the MTM and MPO. The test concentrates on the self-contamination aspects and the resulting performance losses of the solar array under high intensity and elevated temperature environment representative for the photovoltaic assembly (PVA.

  7. Calorimetric Measuring Systems for Characterizing High Frequency Power Losses in Power Electronic Components and Systems

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Pedersen, John Kim; Ritchie, Andrew Ewen

    2002-01-01

    High frequency power losses in power electronic components and systems are very difficult to measure. The same applies to the efficiency of high-efficiency systems and components. An important method to measure losses with high accuracy is the calorimetric measuring systems. This paper describes...... two different calorimetric measuring systems, one for power losses up to 50 W and one for power losses up to 1500 W. These differ in size and also the systems which can be analysed. The basic concept of calorimetry is discussed and the overall performance of the two systems is specified. Methods...

  8. A STUDY ON LOSS & COST MINIMIZATION BY USING HIGH VOLTAGE DISTRIBUTION SYSTEM

    OpenAIRE

    P. Hussain Khan*, Ch. Punya Sekhar

    2016-01-01

    This paper presents a converter free system to improve the loss minimization and to reduce the cost of power distribution. The high voltage distribution system is implemented to reduce the loss in the present distribution system. The detailed cost estimation and loss minimization in high voltage distribution system is calculated through simulation results. These performance analysis are presented in this paper.      

  9. A Novel Low Loss, Highly Birefringent Photonic Crystal Fiber in THz Regime

    DEFF Research Database (Denmark)

    Hasanuzzaman, G. K. M.; Rana, Sohel; Habib, Selim

    2016-01-01

    We present a new kind of dual-hole unit-based porous-core hexagonal photonic crystal fiber (H-PCF) with low loss and high birefringence in terahertz regime. The proposed fiber offers simultaneously high birefringence and low effective material loss (EML) in the frequency range of 0.5-0.85 THz...

  10. Extended high-frequency audiometry and noise induced hearing loss in cement workers.

    Science.gov (United States)

    Somma, Giuseppina; Pietroiusti, Antonio; Magrini, Andrea; Coppeta, Luca; Ancona, Carla; Gardi, Stefano; Messina, Marco; Bergamaschi, Antonio

    2008-06-01

    It has been suggested that extended high-frequency audiometry (EHFA) might be more sensitive than conventional audiometry in detecting early signs of hearing impairment. However, this technique has not been adequately tested in an occupational environment. We therefore investigated the usefulness of this method in noise-exposed workers. We compared conventional frequency audiometry (0.25-8 kHz) and EHFA (9-18 kHz) in 184 noise-exposed and 98 non-noise-exposed workers. Both methods showed significantly higher threshold levels (P audiometry. Stepwise regression analysis showed that in 21- to 40-year-old workers the noise effect was largely predominant at both conventional audiometry and EHFA, whereas in older subjects the noise effect was predominant up to 6 kHz frequency, the effect of age being significantly greater at higher frequencies. These data indicate that EHFA is more sensitive than conventional audiometry in detecting noise induced hearing loss. However, hearing loss in the EHF range seems an age-dependent phenomenon with progression into the lower speech range frequencies with increasing age. These changes seem to be accentuated in the early years by noise exposure, suggesting that EHFA could represent a useful preventive measure in young exposed workers. Copyright 2008 Wiley-Liss, Inc.

  11. Low-Loss Transmission Lines for High-Power Terahertz Radiation.

    Science.gov (United States)

    Nanni, Emilio A; Jawla, Sudheer K; Shapiro, Michael A; Woskov, Paul P; Temkin, Richard J

    2012-07-01

    Applications of high-power Terahertz (THz) sources require low-loss transmission lines to minimize loss, prevent overheating and preserve the purity of the transmission mode. Concepts for THz transmission lines are reviewed with special emphasis on overmoded, metallic, corrugated transmission lines. Using the fundamental HE(11) mode, these transmission lines have been successfully implemented with very low-loss at high average power levels on plasma heating experiments and THz dynamic nuclear polarization (DNP) nuclear magnetic resonance (NMR) experiments. Loss in these lines occurs directly, due to ohmic loss in the fundamental mode, and indirectly, due to mode conversion into high order modes whose ohmic loss increases as the square of the mode index. An analytic expression is derived for ohmic loss in the modes of a corrugated, metallic waveguide, including loss on both the waveguide inner surfaces and grooves. Simulations of loss with the numerical code HFSS are in good agreement with the analytic expression. Experimental tests were conducted to determine the loss of the HE(11) mode in a 19 mm diameter, helically-tapped, three meter long brass waveguide with a design frequency of 330 GHz. The measured loss at 250 GHz was 0.029 ± 0.009 dB/m using a vector network analyzer approach and 0.047 ± 0.01 dB/m using a radiometer. The experimental results are in reasonable agreement with theory. These values of loss, amounting to about 1% or less per meter, are acceptable for the DNP NMR application. Loss in a practical transmission line may be much higher than the loss calculated for the HE(11) mode due to mode conversion to higher order modes caused by waveguide imperfections or miter bends.

  12. Teamwork in high-risk environments analogous to space

    Science.gov (United States)

    Kanki, Barbara G.

    1990-01-01

    Mountaineering expeditions combine a number of factors which make them potentially good analogs to the planetary exploration facet of long-duration space missions. A study of mountain climbing teams was conducted in order to evaluate the usefulness of the environment as a space analog and to specifically identify the factors and issues surrounding teamwork and 'successful' team performance in two mountaineering environments. This paper focuses on social/organizational factors, including team size and structure, leadership styles and authority structure which were found in the sample of 22 climb teams (122 individuals). The second major issue discussed is the construction of a valid performance measure in this high-risk environment.

  13. Hydrodynamic control of phytoplankton loss to the benthos in an estuarine environment

    Science.gov (United States)

    Jones, Nicole L.; Thompson, Janet K.; Arrigo, Kevin R.; Monismith, Stephen G.

    2009-01-01

    Field experiments were undertaken to measure the influence of hydrodynamics on the removal of phytoplankton by benthic grazers in Suisun Slough, North San Francisco Bay. Chlorophyll a concentration boundary layers were found over beds inhabited by the active suspension feeders Corbula amurensis and Corophium alienense and the passive suspension feeders Marenzellaria viridis and Laonome sp. Benthic losses of phytoplankton were estimated via both the control volume and the vertical flux approach, in which chlorophyll a concentration was used as a proxy for phytoplankton biomass. The rate of phytoplankton loss to the bed was positively correlated to the bed shear stress. The maximum rate of phytoplankton loss to the bed was five times larger than estimated by laboratory-derived pumping rates for the active suspension feeders. Reasons for this discrepancy are explored including a physical mechanism whereby phytoplankton is entrained in a near-bed fluff layer where aggregation is mediated by the presence of mucus produced by the infaunal community.

  14. A High-Saturated-Fat, High-Sucrose Diet Aggravates Bone Loss in Ovariectomized Female Rats.

    Science.gov (United States)

    Dong, Xiao-Li; Li, Chun-Mei; Cao, Si-Si; Zhou, Li-Ping; Wong, Man-Sau

    2016-06-01

    Estrogen deficiency in women and high-saturated fat, high-sucrose (HFS) diets have both been recognized as risk factors for metabolic syndrome. Studies on the combined actions of these 2 detrimental factors on the bone in females are limited. We sought to determine the interactive actions of estrogen deficiency and an HFS diet on bone properties and to investigate the underlying mechanisms. Six-month-old Sprague Dawley sham or ovariectomized (OVX) rats were pair fed the same amount of either a low-saturated-fat, low-sucrose (LFS) diet (13% fat calories; 15% sucrose calories) or an HFS diet (42% fat calories; 30% sucrose calories) for 12 wk. Blood, liver, and bone were collected for correspondent parameters measurement. Ovariectomy decreased bone mineral density in the tibia head (TH) by 62% and the femoral end (FE) by 49% (P loss in OVX rats by an additional 41% in the TH and 37% in the FE (P loss in the HFS-OVX rats was accompanied by increased urinary deoxypyridinoline concentrations by 28% (P < 0.05). The HFS diet induced cathepsin K by 145% but reduced osteoprotegerin mRNA expression at the FE of the HFS-sham rats by 71% (P < 0.05). Ovariectomy significantly increased peroxisome proliferator-activated receptor γ mRNA expression by 136% and 170% at the FE of the LFS- and HFS-OVX rats, respectively (P < 0.05). The HFS diet aggravated ovariectomy-induced lipid deposition and oxidative stress (OS) in rat livers (P < 0.05). Trabecular bone mineral density at the FE was negatively correlated with rat liver malondialdehyde concentrations (R(2) = 0.39; P < 0.01). The detrimental actions of the HFS diet and ovariectomy on bone properties in rats occurred mainly in cancellous bones and were characterized by a high degree of bone resorption and alterations in OS. © 2016 American Society for Nutrition.

  15. Dynamics and changing environments in highly optimized tolerance

    Science.gov (United States)

    Zhou; Carlson

    2000-09-01

    Highly optimized tolerance (HOT) is a mechanism for power laws in complex systems based on the robust design of systems in uncertain environments. Once the system, the environment, and the optimization scheme have been specified, the HOT state is fixed and corresponds to the set of measure zero (typically a single point) in the configuration space which minimizes a cost function U. Here we explore the U-dependent structures in configuration space which are associated with departures from the optimal state. We introduce dynamics, quantified by an effective temperature T, such that T=0 corresponds to the original HOT state, while T-->infinity corresponds to completely random configurations. More generally, T defines the range in state space over which fluctuations are likely to be observed. In a fixed environment fluctuations always raise the average cost. However, in a time-dependent environment, mobile configurations can lower the average U because they adjust more efficiently to changes.

  16. PCF Based Sensor with High Sensitivity, High Birefringence and Low Confinement Losses for Liquid Analyte Sensing Applications

    Directory of Open Access Journals (Sweden)

    Huseyin Ademgil

    2015-12-01

    Full Text Available In this paper, we report a design of high sensitivity Photonic Crystal Fiber (PCF sensor with high birefringence and low confinement losses for liquid analyte sensing applications. The proposed PCF structures are designed with supplementary elliptical air holes in the core region vertically-shaped V-PCF and horizontally-shaped H-PCF. The full vectorial Finite Element Method (FEM simulations performed to examine the sensitivity, the confinement losses, the effective refractive index and the modal birefringence features of the proposed elliptical air hole PCF structures. We show that the proposed PCF structures exhibit high relative sensitivity, high birefringence and low confinement losses simultaneously for various analytes.

  17. Modelling the loss of genetic diversity in vole populations in a spatially and temporally varying environment

    DEFF Research Database (Denmark)

    Topping, C; Ostergaard, S; Pertoldi, C

    2003-01-01

    heterogeneity. Results showed that both spatial and temporal heterogeneity exerted an influence on the rate of loss of genetic diversity, but the precise effect was a balance between the effects of population sub-structuring, the frequency of founder effects and population size. These were in turn related...... conditions, but exclude factors such as animal behaviour, environmental structure, and breeding biology, all of which influence genetic diversity. Most populations are unique in some of these characteristics, and therefore may be unsuitable for the classical approach. Here, an alternative approach using...... a genetically explicit individual-based model (IBM) coupled to a dynamic landscape model was used to obtain measures for the genetic status of simulated vole populations. The rate of loss of expected heterozygosity (H-e) was calculated for simulated populations using two levels of spatial and temporal...

  18. High functional load inhibits phonological contrast loss: a corpus study.

    Science.gov (United States)

    Wedel, Andrew; Kaplan, Abby; Jackson, Scott

    2013-08-01

    For nearly a century, linguists have suggested that diachronic merger is less likely between phonemes with a high functional load--that is, phonemes that distinguish many words in the language in question. However, limitations in data and computational power have made assessing this hypothesis difficult. Here we present the first larger-scale study of the functional load hypothesis, using data from sound changes in a diverse set of languages. Our results support the functional load hypothesis: phoneme pairs undergoing merger distinguish significantly fewer minimal pairs in the lexicon than unmerged phoneme pairs. Furthermore, we show that higher phoneme probability is positively correlated with merger, but that this effect is stronger for phonemes that distinguish no minimal pairs. Finally, within our dataset we find that minimal pair count and phoneme probability better predict merger than change in system entropy at the lexical or phoneme level. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Politics in evaluation: Politically responsive evaluation in high stakes environments.

    Science.gov (United States)

    Azzam, Tarek; Levine, Bret

    2015-12-01

    The role of politics has often been discussed in evaluation theory and practice. The political influence of the situation can have major effects on the evaluation design, approach and methods. Politics also has the potential to influence the decisions made from the evaluation findings. The current study focuses on the influence of the political context on stakeholder decision making. Utilizing a simulation scenario, this study compares stakeholder decision making in high and low stakes evaluation contexts. Findings suggest that high stakes political environments are more likely than low stakes environments to lead to reduced reliance on technically appropriate measures and increased dependence on measures better reflect the broader political environment. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Conceptual design in a high-tech environment

    NARCIS (Netherlands)

    Bonnema, Gerrit Maarten; van Houten, Frederikus J.A.M.

    2003-01-01

    This article will give an overview over design process models before concentrating on the main subject: Conceptual Design, which has had less academic attention than the detail design phases. In high-tech environments specific conditions apply. This article will deal with these conditions. Some

  1. Investigating High School Teachers' Perceptions of School Environment.

    Science.gov (United States)

    Huang, Shwu-yong L.

    This study examined public high school teachers' perceptions of school environment, focusing on satisfaction, collegiality, teacher-student relationships, discipline, principal leadership, equity, and teacher influence. It also investigated differences in attitudes by gender. Participating teachers from 8 schools in the Southern United States…

  2. Fibre optic humidity sensor designed for highly alkaline environments

    OpenAIRE

    K. Bremer; Wollweber, M.; Guenther, S.; Werner, G.; Sun, T.; Grattan, K. T. V.; Roth, B.

    2014-01-01

    This paper presents the design of a sensor packaging for a Fibre Bragg Grating (FBG) based fibre optic humidity sensor. The evaluation of the developed fibre optic sensor was performed under experimental conditions and verified its capability to withstand highly alkaline environments. Therefore, the sensor can be applied to monitor the concrete humidity level and thus to indicate the maintenance of concrete structures.

  3. Advocacy for Child Wellness in High-Poverty Environments

    Science.gov (United States)

    Mullen, Carol A.

    2014-01-01

    Child wellness needs to be understood holistically so that children and youth from high-poverty environments can succeed in schooling and life. Teachers who foster advocacy in themselves are well equipped to teach students to take ownership of their own well-being. Such advocacy can enrich the classroom curriculum and mitigate the negative effects…

  4. 24-h Fluid Kinetics and Perception of Sweat Losses Following a 1-h Run in a Temperate Environment

    Directory of Open Access Journals (Sweden)

    Eric K. O'Neal

    2013-12-01

    Full Text Available This study examined 24-h post-run hydration status and sweat loss estimation accuracy in college age runners (men = 12, women = 8 after completing a 1-h self-paced outdoor run (wet bulb globe temperature = 19.9 ± 3.0 °C. Sweat losses (1353 ± 422 mL; 1.9% ± 0.5% of body mass were significantly greater (p < 0.001 than perceived losses (686 ± 586 mL. Cumulative fluid consumption equaled 3876 ± 1133 mL (218 ± 178 mL during with 37% of fluid ingested lost through urine voids (1450 ± 678 mL. Fluid balance based on intake and urine production equaled +554 ± 669 mL at 12 h and +1186 ± 735 mL at 24 h. Most runners reported euhydrated (pre-run urine specific gravity (USG = 1.018 ± 0.008 with no changes (p = 0.33 at hours 12 or 24 when both genders were included. However, USG was higher (p = 0.004 at 12 h post-run for men (1.025 ± 0.0070 vs. 1.014 ± 0.007, who consumed 171% ± 40% of sweat losses at 12 h vs. 268% ± 88% for women. Most runners do not need intervention concerning between bout hydration needs in temperate environments. However, repeated USG measurements were able to identify runners who greatly under or over consumed fluid during recovery. Practitioners can use multiple USG assessments as cheap method to detect runners who need to modify their hydration strategies and should promote assessment of sweat losses by change in body mass, as runners had poor perception of sweat losses.

  5. AC losses of high T{sub c} superconducting coils; Koon chodendo koiru no koryu sonshitsu

    Energy Technology Data Exchange (ETDEWEB)

    Yokoyama, S.; Fukuda, M.; Kawagoe, A.; Sumiyoshi, F. [Kagoshima Univ., Kagoshima (Japan); Hayashi, H.; Irie, F. [Kyushu Electric Power Co., Inc., Fukuoka (Japan)

    2000-05-29

    High temperature superconductive coil expected for future application to electric power equipment has a defect of large AC loss that is a large obstacle for future practicalization. In this study, 13 double pancake coils were experimentally manufactured using Bi-2223 multicore tape wire, and their AC loss characteristics in liquid nitrogen were evaluated. In loss measurement, sample coils were placed in liquid nitrogen, and pure loss components contained in voltage between terminals were detected by lock-in amplifier. Loss characteristics of 3 coils tested all had strong frequency dependency. Though characteristic curve of overcurrent loss of silver which was normal conductive in low current region was conspicuously observed, their absolute values and critical frequency were different depending on coil. (NEDO)

  6. Challenge of Using Passive Acoustic Monitoring in High-Energy Environments: UK Tidal Environments and Other Case Studies.

    Science.gov (United States)

    Booth, Cormac G

    2016-01-01

    The use of passive acoustic monitoring (PAM) around marine developments is commonplace. A buffer-based PAM system (e.g., C-POD) is a cost-effective method for assessing cetacean acoustic presence. Devices have been deployed by Sea Mammal Research Unit (SMRU) Marine around the United Kingdom, allowing an examination of the performance of C-PODs with respect to background noise, tilt angle, and environmental factors. C-PODs were found to often only monitor for a few seconds of each minute, resulting in significant loss of monitoring time. Issues were likely driven by environmental and deployment factors. The practical limitations of buffer-based PAM systems in high-energy/noisy environments are indicated here.

  7. Latent heat loss and sweat gland histology of male goats in an equatorial semi-arid environment

    Science.gov (United States)

    de Melo Costa, Cíntia Carol; Maia, Alex Sandro Campos; Neto, José Domingues Fontenele; Oliveira, Steffan Edward Octávio; de Queiroz, João Paulo Araújo Fernandes

    2014-03-01

    The objective of this work was to quantify the heat loss by cutaneous evaporation of goats in an equatorial semi-arid environment. The latent heat loss from the body surfaces of these ten undefined breed goats was measured using a ventilated capsule in sun and shade and in the three body regions (neck, flank and hindquarters). Skin samples from these three regions were histologically analyzed to relate the quantity of sweat glands, the area of sweat glands and the epithelium thickness of each of these regions to the heat loss by cutaneous evaporation of the examined goats. The epithelium thickness that was measured varied significantly for body regions with different quantities and areas of sweat glands ( P < 0.01). Among the body regions that were examined, the samples from the neck demonstrated the highest epithelium thickness (16.23 ± 0.13 μm). However, the samples of sweat glands from the flank had the biggest area (43330.51 ± 778.71 μm2) and quantity per square centimeter (390 ± 9 cm-2). After the animals were exposed to sun, the flanks lost the greatest amount of heat by cutaneous evaporation (73.03 ± 1.75 W m-2) and possessed the highest surface temperatures (39.47 ± 0.18 °C). The histological characteristics may have influenced the heat loss by cutaneous evaporation that was observed in the flank region after the animals were exposed to sun.

  8. Prestress Loss and Bending Capacity of Pre-cracked 40 Year-Old PC Beams Exposed to Marine Environment

    Directory of Open Access Journals (Sweden)

    Dasar Amry

    2016-01-01

    Full Text Available Six prestressed concrete beams (PC beam were used for evaluation, consist of four post-tension beams (PC-O and two pre-tension beams (PC-R. In order to investigate the effect of crack on prestress loss and bending capacity after long-term exposed, prestressed concrete beams were pre-crack and then exposed to marine environment. Experimental work was carried out to evaluate PC beams performance after long-term exposed. In addition, visual observations and load bearing capacity test was carried out. Furthermore, evaluation of prestress loss conducted using three-point loading bending test and the remaining tendon forces in the beam were determined using Crack Re-opening Method. The experimental results revealed that prestress loss was increased due to corrosion of strand/wire which affected by the pre-crack on the prestressed beams. Approximately a prestress loss around 26% and 30% was recorded for post-tension and pre-tension beams respectively.

  9. A NEW GIS NITROGEN TRADING TOOL CONCEPT FOR CONSERVATION AND REDUCTION OF REACTIVE NITROGEN LOSSES TO THE ENVIRONMENT

    Science.gov (United States)

    Nitrogen inputs to agricultural systems are important for their sustainability. However, when N inputs are unnecessarily high, the excess can contribute to greater agricultural N losses that impact air, surface water and groundwater quality. It is paramount to reduce off-site transport of N by using...

  10. A nominal set of high-altitude EMP environments

    Energy Technology Data Exchange (ETDEWEB)

    Longmire, C.L.; Hamilton, R.M.; Hahn, J.M.

    1987-02-01

    This report presents high-altitude EMP (HEMP) environments calculated by the CHAP code for a nominal large yield burst at 400 km over the central US. Nominal, unclassified weapon output parameters were used, along with unclassified EMP theory and calculational techniques. While the resulting environments do not represent upper bounds, they should be useful in developing understanding of the effect of HEMP on electrical and electronic systems. The calculated environments illustrate the wide variability of the HEMP from a single burst, depending on ground range and azimuth from ground zero. Analytic fits to the HEMP fields are provided to facilitate coupling calculations. The CHAP results are justified by a detailed examination of Compton currents, air conductivities, and the resulting fields. It is shown that both HEMP theory and the calculations conserve energy scrupulously.

  11. Loss of competition in the outside host environment generates outbreaks of environmental opportunist pathogens.

    Science.gov (United States)

    Anttila, Jani; Ruokolainen, Lasse; Kaitala, Veijo; Laakso, Jouni

    2013-01-01

    Environmentally transmitted pathogens face ecological interactions (e.g., competition, predation, parasitism) in the outside-host environment and host immune system during infection. Despite the ubiquitousness of environmental opportunist pathogens, traditional epidemiology focuses on obligatory pathogens incapable of environmental growth. Here we ask how competitive interactions in the outside-host environment affect the dynamics of an opportunist pathogen. We present a model coupling the classical SI and Lotka-Volterra competition models. In this model we compare a linear infectivity response and a sigmoidal infectivity response. An important assumption is that pathogen virulence is traded off with competitive ability in the environment. Removing this trade-off easily results in host extinction. The sigmoidal response is associated with catastrophic appearances of disease outbreaks when outside-host species richness, or overall competition pressure, decreases. This indicates that alleviating outside-host competition with antibacterial substances that also target the competitors can have unexpected outcomes by providing benefits for opportunist pathogens. These findings may help in developing alternative ways of controlling environmental opportunist pathogens.

  12. Factors related to high-level mobility in male servicemembers with traumatic lower-limb loss

    OpenAIRE

    Ignacio A. Gaunaurd, PhD, MSPT; Kathryn E. Roach, PhD, PT; Michele A. Raya, PhD, PT, SCS, ATC; COL (Ret) Rebecca Hooper, PhD, PT; Alison A. Linberg, DPT, ATC; Justin Z. Laferrier, PhD, MSPT, OCS, SCS, ATP, CSCS; MAJ (Ret) Stuart M. Campbell, MPT; COL (Ret) Charles Scoville, PT, DPT; Robert S. Gailey, PhD, PT

    2013-01-01

    The purpose of this study was to examine the possible relationship between factors modifiable by rehabilitation interventions (rehabilitation factors), other factors related to lower-limb loss (other factors), and high-level mobility as measured by the Comprehensive High-Level Activity Mobility Predictor (CHAMP) in servicemembers (SMs) with traumatic lower-limb loss. One-hundred eighteen male SMs with either unilateral transtibial amputation (TTA), unilateral transfemoral amputation (TFA), or...

  13. Implement and application of ultra-high pressures environment

    Science.gov (United States)

    Xian Zhang, Yu; Li, Nan; Liu, Bin Bin; Wang, Hong

    2017-09-01

    A hydraulic system was designed which was used to generate hydrostatic ultra-high pressure environment. The functions and roles of the main elements in the hydraulic system were introduced. Deformation theory based on ultrahigh pressure cylinder was analyzed. The principle and method about measuring ultra-high pressure cylinder radial and circumferential elastic line-strain by a dial indicator were illustrated. A practical example was given to illustrate the practicability and validity of this method. The measures to decrease the measurement error were pointed out. The described priciples and methods have a certain theoretical and practical significance in engineering research and application of ultra-high pressure.

  14. A Review on Investigation and Assessment of Path Loss Models in Urban and Rural Environment

    Science.gov (United States)

    Maurya, G. R.; Kokate, P. A.; Lokhande, S. K.; Shrawankar, J. A.

    2017-08-01

    This paper aims at providing a clear knowledge of Path Loss (PL) to the researcher. The important data have been extracted from the papers and mentioned in clear and precise manner. The limited studies were based on identification of PL due to FM frequency. Majority of studies based on identification of PL considering telephonic frequency as a source. In this paper the PL in urban and rural areas of different places due to various factors like buildings, trees, antenna height, forest etc. have been studied. The common parameters like frequency, model and location based studies were done. The studies were segregated based on various parameters in tabular format and they were compared based on frequency, location and best fit model in that table. Scatter chart was drawn in order to make the things clearer and more understandable. However, location specific PL models are required to investigate the RF propagation in identified terrain.

  15. Spectroscopic gamma camera for use in high dose environments

    Science.gov (United States)

    Ueno, Yuichiro; Takahashi, Isao; Ishitsu, Takafumi; Tadokoro, Takahiro; Okada, Koichi; Nagumo, Yasushi; Fujishima, Yasutake; Kometani, Yutaka; Suzuki, Yasuhiko; Umegaki, Kikuo

    2016-06-01

    We developed a pinhole gamma camera to measure distributions of radioactive material contaminants and to identify radionuclides in extraordinarily high dose regions (1000 mSv/h). The developed gamma camera is characterized by: (1) tolerance for high dose rate environments; (2) high spatial and spectral resolution for identifying unknown contaminating sources; and (3) good usability for being carried on a robot and remotely controlled. These are achieved by using a compact pixelated detector module with CdTe semiconductors, efficient shielding, and a fine resolution pinhole collimator. The gamma camera weighs less than 100 kg, and its field of view is an 8 m square in the case of a distance of 10 m and its image is divided into 256 (16×16) pixels. From the laboratory test, we found the energy resolution at the 662 keV photopeak was 2.3% FWHM, which is enough to identify the radionuclides. We found that the count rate per background dose rate was 220 cps h/mSv and the maximum count rate was 300 kcps, so the maximum dose rate of the environment where the gamma camera can be operated was calculated as 1400 mSv/h. We investigated the reactor building of Unit 1 at the Fukushima Dai-ichi Nuclear Power Plant using the gamma camera and could identify the unknown contaminating source in the dose rate environment that was as high as 659 mSv/h.

  16. Spectroscopic gamma camera for use in high dose environments

    Energy Technology Data Exchange (ETDEWEB)

    Ueno, Yuichiro, E-mail: yuichiro.ueno.bv@hitachi.com [Research and Development Group, Hitachi, Ltd., Hitachi-shi, Ibaraki-ken 319-1221 (Japan); Takahashi, Isao; Ishitsu, Takafumi; Tadokoro, Takahiro; Okada, Koichi; Nagumo, Yasushi [Research and Development Group, Hitachi, Ltd., Hitachi-shi, Ibaraki-ken 319-1221 (Japan); Fujishima, Yasutake; Kometani, Yutaka [Hitachi Works, Hitachi-GE Nuclear Energy, Ltd., Hitachi-shi, Ibaraki-ken (Japan); Suzuki, Yasuhiko [Measuring Systems Engineering Dept., Hitachi Aloka Medical, Ltd., Ome-shi, Tokyo (Japan); Umegaki, Kikuo [Faculty of Engineering, Hokkaido University, Sapporo-shi, Hokkaido (Japan)

    2016-06-21

    We developed a pinhole gamma camera to measure distributions of radioactive material contaminants and to identify radionuclides in extraordinarily high dose regions (1000 mSv/h). The developed gamma camera is characterized by: (1) tolerance for high dose rate environments; (2) high spatial and spectral resolution for identifying unknown contaminating sources; and (3) good usability for being carried on a robot and remotely controlled. These are achieved by using a compact pixelated detector module with CdTe semiconductors, efficient shielding, and a fine resolution pinhole collimator. The gamma camera weighs less than 100 kg, and its field of view is an 8 m square in the case of a distance of 10 m and its image is divided into 256 (16×16) pixels. From the laboratory test, we found the energy resolution at the 662 keV photopeak was 2.3% FWHM, which is enough to identify the radionuclides. We found that the count rate per background dose rate was 220 cps h/mSv and the maximum count rate was 300 kcps, so the maximum dose rate of the environment where the gamma camera can be operated was calculated as 1400 mSv/h. We investigated the reactor building of Unit 1 at the Fukushima Dai-ichi Nuclear Power Plant using the gamma camera and could identify the unknown contaminating source in the dose rate environment that was as high as 659 mSv/h.

  17. High-rise Buildings versus Outdoor Thermal Environment in Chongqing.

    Science.gov (United States)

    Lu, Jun; Chen, Jin-Hua; Tang, Ying; Wang, Jin-Sha

    2007-10-11

    This paper gives a brief description of the over quick urbanization sinceChongqing, one of the biggest cities in China, has been a municipality directly under theCentral Government in 1997, excessive development and exceeding increase of high-risebuildings because of its special geographical position which finally leads to the worseningof the urban outdoor thermal environment. Then, this paper makes a bright balance to thefield measurement and simulated results of the wind speed field, temperature field of onemultifunctional high-rise building in Chongqing university located in the city center, andthe contrasted results validate the correctness of CFD in the outdoor thermal environmentalsimulation, expose the disadvantages of high-rise buildings on the aspects of blocking thewind field, decreasing wind speed which results in accumulation of the air-conditioningheat revolving around and periscian region where sunshine can not rip into. Finally, inorder to improve the urban outdoor thermal environment near the high-rise buildingsespecially for the angle of natural ventilation, this paper simulates the wind environment indifferent architectural compositions and architectural layouts by CFD, and the simulatedresults show that freestyle and tower buildings which can guarantee the wind speed andtake the air-conditioning heat away are much suitable and reasonable for the specialChongqing geography. These conclusions can also be used as a reference in othermountain cities, especially for the one with a great number of populations.

  18. High-rise Buildings versus Outdoor Thermal Environment in Chongqing

    Directory of Open Access Journals (Sweden)

    Jin-sha Wang

    2007-10-01

    Full Text Available This paper gives a brief description of the over quick urbanization sinceChongqing, one of the biggest cities in China, has been a municipality directly under theCentral Government in 1997, excessive development and exceeding increase of high-risebuildings because of its special geographical position which finally leads to the worseningof the urban outdoor thermal environment. Then, this paper makes a bright balance to thefield measurement and simulated results of the wind speed field, temperature field of onemultifunctional high-rise building in Chongqing university located in the city center, andthe contrasted results validate the correctness of CFD in the outdoor thermal environmentalsimulation, expose the disadvantages of high-rise buildings on the aspects of blocking thewind field, decreasing wind speed which results in accumulation of the air-conditioningheat revolving around and periscian region where sunshine can not rip into. Finally, inorder to improve the urban outdoor thermal environment near the high-rise buildingsespecially for the angle of natural ventilation, this paper simulates the wind environment indifferent architectural compositions and architectural layouts by CFD, and the simulatedresults show that freestyle and tower buildings which can guarantee the wind speed andtake the air-conditioning heat away are much suitable and reasonable for the specialChongqing geography. These conclusions can also be used as a reference in othermountain cities, especially for the one with a great number of populations.

  19. The development of advanced robotics technology in high radiation environment

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yong Bum; Cho, Jaiwan; Lee, Nam Ho; Choi, Young Soo; Park, Soon Yong; Lee, Jong Min; Park, Jin Suk; Kim, Seung Ho; Kim, Byung Soo; Moon, Byung Soo

    1997-07-01

    In the tele-operation technology using tele-presence in high radiation environment, stereo vision target tracking by centroid method, vergence control of stereo camera by moving vector method, stereo observing system by correlation method, horizontal moving axis stereo camera, and 3 dimensional information acquisition by stereo image is developed. Also, gesture image acquisition by computer vision and construction of virtual environment for remote work in nuclear power plant. In the development of intelligent control and monitoring technology for tele-robot in hazardous environment, the characteristics and principle of robot operation. And, robot end-effector tracking algorithm by centroid method and neural network method are developed for the observation and survey in hazardous environment. 3-dimensional information acquisition algorithm by structured light is developed. In the development of radiation hardened sensor technology, radiation-hardened camera module is designed and tested. And radiation characteristics of electric components is robot system is evaluated. Also 2-dimensional radiation monitoring system is developed. These advanced critical robot technology and telepresence techniques developed in this project can be applied to nozzle-dam installation /removal robot system, can be used to realize unmanned remotelization of nozzle-dam installation / removal task in steam generator of nuclear power plant, which can be contributed for people involved in extremely hazardous high radioactivity area to eliminate their exposure to radiation, enhance their task safety, and raise their working efficiency. (author). 75 refs., 21 tabs., 15 figs.

  20. High Temperature Wireless Communication And Electronics For Harsh Environment Applications

    Science.gov (United States)

    Hunter, G. W.; Neudeck, P. G.; Beheim, G. M.; Ponchak, G. E.; Chen, L.-Y

    2007-01-01

    In order for future aerospace propulsion systems to meet the increasing requirements for decreased maintenance, improved capability, and increased safety, the inclusion of intelligence into the propulsion system design and operation becomes necessary. These propulsion systems will have to incorporate technology that will monitor propulsion component conditions, analyze the incoming data, and modify operating parameters to optimize propulsion system operations. This implies the development of sensors, actuators, and electronics, with associated packaging, that will be able to operate under the harsh environments present in an engine. However, given the harsh environments inherent in propulsion systems, the development of engine-compatible electronics and sensors is not straightforward. The ability of a sensor system to operate in a given environment often depends as much on the technologies supporting the sensor element as the element itself. If the supporting technology cannot handle the application, then no matter how good the sensor is itself, the sensor system will fail. An example is high temperature environments where supporting technologies are often not capable of operation in engine conditions. Further, for every sensor going into an engine environment, i.e., for every new piece of hardware that improves the in-situ intelligence of the components, communication wires almost always must follow. The communication wires may be within or between parts, or from the engine to the controller. As more hardware is added, more wires, weight, complexity, and potential for unreliability is also introduced. Thus, wireless communication combined with in-situ processing of data would significantly improve the ability to include sensors into high temperature systems and thus lead toward more intelligent engine systems. NASA Glenn Research Center (GRC) is presently leading the development of electronics, communication systems, and sensors capable of prolonged stable

  1. Performance of a high T (sub c) superconducting ultra-low loss microwave stripline filter

    Science.gov (United States)

    Bautista, J. J.; Ortiz, G.; Zahopoulos, C.; Sridhar, S.; Lanagan, M.

    1991-01-01

    Discussed here is the successful fabrication of a five-pole interdigital stripline filter made of the 93 K superconductor (Y1Ba2Cu3O sub y) coated on a silver substrate, with center frequency of 8.5 GHz and an extremely high rejection ratio of 80 dB. The lowest injection loss measured was 0.1 dB at 12 K, with a return loss of better than 16 dB, representing a significant improvement over a similar copper filter, and is comparable to low critical temperature filters. The insertion loss appears to be limited by extrinsic factors, such as tuning mismatch and joint losses, and not by superconducting material losses.

  2. Performance of a high Tc superconducting ultralow-loss microwave stripline filter

    Science.gov (United States)

    Zahopoulos, C.; Sridhar, S.; Bautista, J. J.; Ortiz, G.; Lanagan, M.

    1991-01-01

    The successful fabrication is reported of a five-pole interdigital stripline filter made of the 93 K superconductor Y1Ba2Cu3O(y) coated on a silver substrate, with a center frequency of 8.5 GHz and an extremely high rejection ratio of 80 dB. The lowest insertion loss measured was 0.1 dB at 12 K, with a return loss better than 16 dB, representing significant improvements over a similar Cu filter, and comparable to low Tc filters. The insertion loss appears to be limited by extrinsic factors such as tuning mismatch and joint losses, and not by the superconducting material losses.

  3. High-rise Buildings versus Outdoor Thermal Environment in Chongqing

    OpenAIRE

    Lu, Jun; Chen, Jin-hua; Tang, Ying; Wang, Jin-sha

    2007-01-01

    This paper gives a brief description of the over quick urbanization sinceChongqing, one of the biggest cities in China, has been a municipality directly under theCentral Government in 1997, excessive development and exceeding increase of high-risebuildings because of its special geographical position which finally leads to the worseningof the urban outdoor thermal environment. Then, this paper makes a bright balance to thefield measurement and simulated results of the wind speed field, temper...

  4. Virtual team performance in a highly competitive environment

    OpenAIRE

    Algesheimer, René; Dholakia, Utpal M; Gurău, Călin

    2011-01-01

    In this article, we empirically validate a version of the input-mediator-output-input (IMOI) model (Ilgen, Hollenbeck, Johnson, & Jundt, 2005), adapting it to investigate virtual team performance in a highly competitive environment. Our hypotheses are tested using structural equation modeling across time periods with data obtained from 606 professional online gaming teams belonging to the European Electronic Sports League. The findings validate the hypothesized IMOI model, and demonstrate the...

  5. Volume Attenuation and High Frequency Loss as Auditory Depth Cues in Stereoscopic 3D Cinema

    Science.gov (United States)

    Manolas, Christos; Pauletto, Sandra

    2014-09-01

    Assisted by the technological advances of the past decades, stereoscopic 3D (S3D) cinema is currently in the process of being established as a mainstream form of entertainment. The main focus of this collaborative effort is placed on the creation of immersive S3D visuals. However, with few exceptions, little attention has been given so far to the potential effect of the soundtrack on such environments. The potential of sound both as a means to enhance the impact of the S3D visual information and to expand the S3D cinematic world beyond the boundaries of the visuals is large. This article reports on our research into the possibilities of using auditory depth cues within the soundtrack as a means of affecting the perception of depth within cinematic S3D scenes. We study two main distance-related auditory cues: high-end frequency loss and overall volume attenuation. A series of experiments explored the effectiveness of these auditory cues. Results, although not conclusive, indicate that the studied auditory cues can influence the audience judgement of depth in cinematic 3D scenes, sometimes in unexpected ways. We conclude that 3D filmmaking can benefit from further studies on the effectiveness of specific sound design techniques to enhance S3D cinema.

  6. Titanium Dioxide Engineered for Near-dispersionless High Terahertz Permittivity and Ultra-low-loss.

    Science.gov (United States)

    Yu, Chuying; Zeng, Yang; Yang, Bin; Donnan, Robert; Huang, Jinbao; Xiong, Zhaoxian; Mahajan, Amit; Shi, Baogui; Ye, Haitao; Binions, Russell; Tarakina, Nadezda V; Reece, Mike J; Yan, Haixue

    2017-07-26

    Realising engineering ceramics to serve as substrate materials in high-performance terahertz(THz) that are low-cost, have low dielectric loss and near-dispersionless broadband, high permittivity, is exceedingly demanding. Such substrates are deployed in, for example, integrated circuits for synthesizing and converting nonplanar and 3D structures into planar forms. The Rutile form of titanium dioxide (TiO2) has been widely accepted as commercially economical candidate substrate that meets demands for both low-loss and high permittivities at sub-THz bands. However, the relationship between its mechanisms of dielectric response to the microstructure have never been systematically investigated in order to engineer ultra-low dielectric-loss and high value, dispersionless permittivities. Here we show TiO2 THz dielectrics with high permittivity (ca. 102.30) and ultra-low loss (ca. 0.0042). These were prepared by insight gleaned from a broad use of materials characterisation methods to successfully engineer porosities, second phase, crystallography shear-planes and oxygen vacancies during sintering. The dielectric loss achieved here is not only with negligible dispersion over 0.2-0.8 THz, but also has the lowest value measured for known high-permittivity dielectrics. We expect the insight afforded by this study will underpin the development of subwavelength-scale, planar integrated circuits, compact high Q-resonators and broadband, slow-light devices in the THz band.

  7. The effects of high protein diets on thermogenesis, satiety and weight loss: a critical review.

    Science.gov (United States)

    Halton, Thomas L; Hu, Frank B

    2004-10-01

    For years, proponents of some fad diets have claimed that higher amounts of protein facilitate weight loss. Only in recent years have studies begun to examine the effects of high protein diets on energy expenditure, subsequent energy intake and weight loss as compared to lower protein diets. In this study, we conducted a systematic review of randomized investigations on the effects of high protein diets on dietary thermogenesis, satiety, body weight and fat loss. There is convincing evidence that a higher protein intake increases thermogenesis and satiety compared to diets of lower protein content. The weight of evidence also suggests that high protein meals lead to a reduced subsequent energy intake. Some evidence suggests that diets higher in protein result in an increased weight loss and fat loss as compared to diets lower in protein, but findings have not been consistent. In dietary practice, it may be beneficial to partially replace refined carbohydrate with protein sources that are low in saturated fat. Although recent evidence supports potential benefit, rigorous longer-term studies are needed to investigate the effects of high protein diets on weight loss and weight maintenance.

  8. AC Losses and Their Thermal Effect in High Temperature Superconducting Machines

    DEFF Research Database (Denmark)

    Song, Xiaowei (Andy); Mijatovic, Nenad; Zou, Shengnan

    2015-01-01

    In transient operations or fault conditions, high temperature superconducting (HTS) machines suffer AC losses which have an influence on the thermal stability of superconducting windings. In this paper, a method to calculate AC losses and their thermal effect in HTS machines is presented....... The method consists of three sub-models that are coupled only in one direction. The magnetic field distribution is first solved in a machine model, assuming a uniform current distribution in HTS windings. The magnetic fields on the boundaries are then used as inputs for an AC loss model which has...... an HTS machine and its cooling system....

  9. Accuracy of Mobile-Based Audiometry in the Evaluation of Hearing Loss in Quiet and Noisy Environments.

    Science.gov (United States)

    Saliba, Joe; Al-Reefi, Mahmoud; Carriere, Junie S; Verma, Neil; Provencal, Christiane; Rappaport, Jamie M

    2017-04-01

    Objectives (1) To compare the accuracy of 2 previously validated mobile-based hearing tests in determining pure tone thresholds and screening for hearing loss. (2) To determine the accuracy of mobile audiometry in noisy environments through noise reduction strategies. Study Design Prospective clinical study. Setting Tertiary hospital. Subjects and Methods Thirty-three adults with or without hearing loss were tested (mean age, 49.7 years; women, 42.4%). Air conduction thresholds measured as pure tone average and at individual frequencies were assessed by conventional audiogram and by 2 audiometric applications (consumer and professional) on a tablet device. Mobile audiometry was performed in a quiet sound booth and in a noisy sound booth (50 dB of background noise) through active and passive noise reduction strategies. Results On average, 91.1% (95% confidence interval [95% CI], 89.1%-93.2%) and 95.8% (95% CI, 93.5%-97.1%) of the threshold values obtained in a quiet sound booth with the consumer and professional applications, respectively, were within 10 dB of the corresponding audiogram thresholds, as compared with 86.5% (95% CI, 82.6%-88.5%) and 91.3% (95% CI, 88.5%-92.8%) in a noisy sound booth through noise cancellation. When screening for at least moderate hearing loss (pure tone average >40 dB HL), the consumer application showed a sensitivity and specificity of 87.5% and 95.9%, respectively, and the professional application, 100% and 95.9%. Overall, patients preferred mobile audiometry over conventional audiograms. Conclusion Mobile audiometry can correctly estimate pure tone thresholds and screen for moderate hearing loss. Noise reduction strategies in mobile audiometry provide a portable effective solution for hearing assessments outside clinical settings.

  10. High-Performance, Radiation-Hardened Electronics for Space Environments

    Science.gov (United States)

    Keys, Andrew S.; Watson, Michael D.; Frazier, Donald O.; Adams, James H.; Johnson, Michael A.; Kolawa, Elizabeth A.

    2007-01-01

    The Radiation Hardened Electronics for Space Environments (RHESE) project endeavors to advance the current state-of-the-art in high-performance, radiation-hardened electronics and processors, ensuring successful performance of space systems required to operate within extreme radiation and temperature environments. Because RHESE is a project within the Exploration Technology Development Program (ETDP), RHESE's primary customers will be the human and robotic missions being developed by NASA's Exploration Systems Mission Directorate (ESMD) in partial fulfillment of the Vision for Space Exploration. Benefits are also anticipated for NASA's science missions to planetary and deep-space destinations. As a technology development effort, RHESE provides a broad-scoped, full spectrum of approaches to environmentally harden space electronics, including new materials, advanced design processes, reconfigurable hardware techniques, and software modeling of the radiation environment. The RHESE sub-project tasks are: SelfReconfigurable Electronics for Extreme Environments, Radiation Effects Predictive Modeling, Radiation Hardened Memory, Single Event Effects (SEE) Immune Reconfigurable Field Programmable Gate Array (FPGA) (SIRF), Radiation Hardening by Software, Radiation Hardened High Performance Processors (HPP), Reconfigurable Computing, Low Temperature Tolerant MEMS by Design, and Silicon-Germanium (SiGe) Integrated Electronics for Extreme Environments. These nine sub-project tasks are managed by technical leads as located across five different NASA field centers, including Ames Research Center, Goddard Space Flight Center, the Jet Propulsion Laboratory, Langley Research Center, and Marshall Space Flight Center. The overall RHESE integrated project management responsibility resides with NASA's Marshall Space Flight Center (MSFC). Initial technology development emphasis within RHESE focuses on the hardening of Field Programmable Gate Arrays (FPGA)s and Field Programmable Analog

  11. INVESTIGATION OF LOSSES IN INSULATION OF HIGH-VOLTAGE CABLES WITH XLPE INSULATION

    Directory of Open Access Journals (Sweden)

    L.A. Shchebeniuk

    2016-09-01

    Full Text Available In this paper the authors calculate the losses in insulation system cable with XLPE-polyethylene as a solid dielectric insulation and with semiconductor polyethylene used as a conductor screen and a insulation screen. The paper is devoted to the investigation of losses in the insulation system of high- voltage XLPE-cables. The line of XLPE-cables in group running horizontally, provided that the cables are of equal diameter and emit equal losses. It is limited to the following: the air flow around the cables may be necessary restricted by proximity to next cables. The dielectric losses are voltage depended and related to the insulation system materials being used. All current in this insulation system are complex quantities containing both real (Re(I and imaginary (Im(I parts. Values of the loss factor of the insulation system at power frequency tgd are given astgd = Re(I/Im(I. It was proposed the quantities criterion of the loss factor of the insulation system to high voltage XLPE-cables. The work is devoted to creation of a method for calculation of the current rating of high-voltage cables in conditions function.

  12. Decision making in high-velocity environments: implications for healthcare.

    Science.gov (United States)

    Stepanovich, P L; Uhrig, J D

    1999-01-01

    Healthcare can be considered a high-velocity environment and, as such, can benefit from research conducted in other industries regarding strategic decision making. Strategic planning is not only relevant to firms in high-velocity environments, but is also important for high performance and survival. Specifically, decision-making speed seems to be instrumental in differentiating between high and low performers; fast decision makers outperform slow decision makers. This article outlines the differences between fast and slow decision makers, identifies five paralyses that can slow decision making in healthcare, and outlines the role of a planning department in circumventing these paralyses. Executives can use the proposed planning structure to improve both the speed and quality of strategic decisions. The structure uses planning facilitators to avoid the following five paralyses: 1. Analysis. Decision makers can no longer afford the luxury of lengthy, detailed analysis but must develop real-time systems that provide appropriate, timely information. 2. Alternatives. Many alternatives (beyond the traditional two or three) need to be considered and the alternatives must be evaluated simultaneously. 3. Group Think. Decision makers must avoid limited mind-sets and autocratic leadership styles by seeking out independent, knowledgeable counselors. 4. Process. Decision makers need to resolve conflicts through "consensus with qualification," as opposed to waiting for everyone to come on board. 5. Separation. Successful implementation requires a structured process that cuts across disciplines and levels.

  13. Novel High Negative Chromatic Dispersion Photonic Crystal Fiber with Low Confinement Loss

    Directory of Open Access Journals (Sweden)

    OUADAH Mohammed Chamse Eddine

    2016-05-01

    Full Text Available In this paper, we propose a novel dual core concentric photonic crystal fiber with high negative chromatic dispersion and low confinement loss. Finite element method with perfectly matched layers (PMLS is used to investigate the guiding properties. In order to achieve a high negative chromatic dispersion, small air holes are added in the inner core as well as the liquid filling the outer core. The numerical results show a negative dispersion coefficient and confinement loss of -78010ps/nm/km, 0.05dB/km respectively at λ=155μm, which make the proposed design an excellent device in high transmission system for dispersion compensation.

  14. Awareness of Consequence of High School Students on Loss of Bio-Diversity

    Science.gov (United States)

    Kasot, Nazim; Özbas, Serap

    2015-01-01

    The aim of this study is to assess the egoistic, altruistic and biospheric awareness of the consequence of high school students regarding the loss of bio-diversity, then comparing the results on the basis of some independent variables (gender, class and family income). The research data were collected from 884 ninth and tenth grade high school…

  15. High versus low crewmember autonomy in space simulation environments

    Science.gov (United States)

    Kanas, Nick; Saylor, Stephanie; Harris, Matthew; Neylan, Thomas; Boyd, Jennifer; Weiss, Daniel S.; Baskin, Pamela; Cook, Colleen; Marmar, Charles

    2010-10-01

    Given the long distances involved and the kinds of activities planned, crewmembers participating in long-duration exploratory space missions such as an expedition to Mars will have more autonomy than in previous space missions. In order to study the impact of high versus low crew autonomy on crewmembers and the crew-mission control interaction, we conducted a series of pilot studies involving three space simulation settings: NEEMO missions, the Haughton-Mars Project, and the pilot phase of the Mars 500 Program. As in our previous on-orbit studies on the Mir and International Space Station, crew and mission control subjects working in missions involving these three settings completed a weekly study questionnaire that assessed mood and interpersonal interactions using the Profile of Mood States, the Group Environment Scale, and the Work Environment Scale. The Mars 500 pilot study also directly assessed individual and group autonomy. In these studies, high autonomy periods were those where crewmembers planned much of their work schedule, whereas low autonomy periods were those where mission control personnel developed the schedule, much as happens now during actual space flight conditions. Our results suggested that high work autonomy was well-received by the crews, mission goals were accomplished, and there were no adverse effects. During high autonomy periods, crewmember mood was generally reported as being better and creativity was higher, but mission control personnel reported some confusion about their work role. The crewmember group environment in the Mars 500 pilot study was dependent on the nationality mix. Despite scoring lower in work pressure overall, the four Russian crewmembers reported a greater rise in work pressure from low to high autonomy than the two Europeans. In contrast, the European crewmembers reported a greater rise in dysphoric mood in going from low to high autonomy, whereas the Russians' emotional state remained the same or slightly

  16. Ramping turn-to-turn loss and magnetization loss of a No-Insulation (RE)Ba2Cu3Ox high temperature superconductor pancake coil

    Science.gov (United States)

    Wang, Y.; Song, H.; Yuan, W.; Jin, Z.; Hong, Z.

    2017-03-01

    This paper is to study ramping turn-to-turn loss and magnetization loss of a no-insulation (NI) high temperature superconductor (HTS) pancake coil wound with (RE)Ba2Cu3Ox (REBCO) conductors. For insulated (INS) HTS coils, a magnetization loss occurs on superconducting layers during a ramping operation. For the NI HTS coil, additional loss is generated by the "bypassing" current on the turn-to-turn metallic contacts, which is called "turn-to-turn loss" in this study. Therefore, the NI coil's ramping loss is much different from that of the INS coil, but few studies have been reported on this aspect. To analyze the ramping losses of NI coils, a numerical method is developed by coupling an equivalent circuit network model and a H-formulation finite element method model. The former model is to calculate NI coil's current distribution and turn-to-turn loss, and the latter model is to calculate the magnetization loss. A test NI pancake coil is wound with REBCO tapes and the reliability of this model is validated by experiments. Then the characteristics of the NI coil's ramping losses are studied using this coupling model. Results show that the turn-to-turn loss is much higher than the magnetization loss. The NI coil's total ramping loss is much higher than that of its insulated counterpart, which has to be considered carefully in the design and operation of NI applications. This paper also discusses the possibility to reduce NI coil's ramping loss by decreasing the ramping rate of power supply or increasing the coil's turn-to-turn resistivity.

  17. Chemical Vapor Deposition at High Pressure in a Microgravity Environment

    Science.gov (United States)

    McCall, Sonya; Bachmann, Klaus; LeSure, Stacie; Sukidi, Nkadi; Wang, Fuchao

    1999-01-01

    In this paper we present an evaluation of critical requirements of organometallic chemical vapor deposition (OMCVD) at elevated pressure for a channel flow reactor in a microgravity environment. The objective of using high pressure is to maintain single-phase surface composition for materials that have high thermal decomposition pressure at their optimum growth temperature. Access to microgravity is needed to maintain conditions of laminar flow, which is essential for process analysis. Based on ground based observations we present an optimized reactor design for OMCVD at high pressure and reduced gravity. Also, we discuss non-intrusive real-time optical monitoring of flow dynamics coupled to homogeneous gas phase reactions, transport and surface processes. While suborbital flights may suffice for studies of initial stages of heteroepitaxy experiments in space are essential for a complete evaluation of steady-state growth.

  18. High ambient temperature reduces rate of body-weight loss produced by wheel running.

    Science.gov (United States)

    Gutiérrez, Emilio; Baysari, Melissa T; Carrera, Olaia; Whitford, Thomas J; Boakes, Robert A

    2006-07-01

    This study examined the effect of ambient temperature (AT) on the relationship between activity and weight loss. Compared with a neutral AT of 21 degrees C, high ATs of 27-29 degrees C produced a slower rate of weight loss in rats given 1.5-hr food access and 22.5-hr running-wheel access in a standard activity-based anorexia (ABA) procedure (Experiments 1 and 2). The high AT did not affect food intake or wheel running in Experiment 1, but did reduce running in Experiment 2. Switching from neutral to high AT had only a transient effect on weight loss when wheel access was maintained (Experiment 2) but resulted in less weight loss when wheel access was prevented (Experiment 3). Giving rats only 3 hr of wheel access each day at a neutral AT also produced substantial weight loss, but less if for the rest of each day they were maintained at a high AT (Experiment 4).

  19. Microbial growth under a high-pressure CO2 environment

    Science.gov (United States)

    Thompson, J. R.; Hernandez, H. H.

    2009-12-01

    Carbon capture and storage (CCS) of CO2 has the potential to significantly reduce the emission of greenhouse gasses associated with fossil fuel combustion. The largest potential for storing captured CO2 in the United Sates is in deep geologic saline formations. Currently, little is known about the effects of CO2 storage on biologically active microbial communities found in the deep earth biosphere. Therefore, to investigate how deep earth microbial communities will be affected by the storage of CO2, we have built a high-pressure microbial growth system in which microbial samples are subjected to a supercritical CO2 (scCO2) environment. Recently we have isolated a microbial consortium that is capable of growth and extracellular matrix production in nutrient media under a supercritical CO2 headspace. This consortium was cultivated from hydrocarbon residues associated with saline formation waters and includes members of the gram-positive Bacillus genus. The cultivation of actively growing cells in an environment containing scCO2 is unexpected based on previous experimental evidence of microbial sterilization attributed to the acidic, desiccating, and solvent-like properties of scCO2. Such microbial consortia have potential for development as (i) biofilm barriers for geological carbon-dioxide sequestration, and as (ii) agents of biocatalysis in environmentally-friendly supercritical (sc) CO2 solvent systems. The discovery that microbes can remain biologically active, and grow, in these environments opens new frontiers for the use of self-regenerating biological systems in engineering applications.

  20. Morphological study of silver corrosion in highly aggressive sulfur environments

    DEFF Research Database (Denmark)

    Minzari, Daniel; Jellesen, Morten Stendahl; Møller, Per

    2011-01-01

    the silicone coating to the interface has resulted in three corrosion types namely: uniform corrosion, conductive anodic filament type of Ag2S growth, and silver migration with subsequent formation of sulfur compounds. Detailed morphological investigation of new and corroded power modules was carried out......A silicone coated power module, having silver conducting lines, showed severe corrosion, after prolonged use as part of an electronic device in a pig farm environment, where sulfur containing corrosive gasses are known to exist in high amounts. Permeation of sulfur gasses and humidity through...

  1. Mitigated-force carriage for high magnetic field environments

    Science.gov (United States)

    Ludtka, Gerard M.; Ludtka, Gail M.; Wilgen, John B.; Murphy, Bart L.

    2015-05-19

    A carriage for high magnetic field environments includes a plurality of work-piece separators disposed in an operable relationship with a work-piece processing magnet having a magnetic field strength of at least 1 Tesla for supporting and separating a plurality of work-pieces by a preselected, essentially equal spacing, so that, as a first work-piece is inserted into the magnetic field, a second work-piece is simultaneously withdrawn from the magnetic field, so that an attractive magnetic force imparted on the first work-piece offsets a resistive magnetic force imparted on the second work-piece.

  2. Regional-scale Predictions of Agricultural N Losses in an Area with a High Livestock Density

    Directory of Open Access Journals (Sweden)

    Carlo Grignani

    2011-02-01

    Full Text Available The quantification of the N losses in territories characterised by intensive animal stocking is of primary importance. The development of simulation models coupled to a GIS, or of simple environmental indicators, is strategic to suggest the best specific management practices. The aims of this work were: a to couple a GIS to a simulation model in order to predict N losses; b to estimate leaching and gaseous N losses from a territory with intensive livestock farming; c to derive a simplified empirical metamodel from the model output that could be used to rank the relative importance of the variables which influence N losses and to extend the results to homogeneous situations. The work was carried out in a 7773 ha area in the Western Po plain in Italy. This area was chosen because it is characterised by intensive animal husbandry and might soon be included in the nitrate vulnerable zones. The high N load, the shallow water table and the coarse type of sub-soil sediments contribute to the vulnerability to N leaching. A CropSyst simulation model was coupled to a GIS, to account for the soil surface N budget. A linear multiple regression approach was used to describe the influence of a series of independent variables on the N leaching, the N gaseous losses (including volatilisation and denitrification and on the sum of the two. Despite the fact that the available GIS was very detailed, a great deal of information necessary to run the model was lacking. Further soil measurements concerning soil hydrology, soil nitrate content and water table depth proved very valuable to integrate the data contained in the GIS in order to produce reliable input for the model. The results showed that the soils influence both the quantity and the pathways of the N losses to a great extent. The ratio between the N losses and the N supplied varied between 20 and 38%. The metamodel shows that manure input always played the most important role in determining the N losses

  3. Radiation and Internal Loss Engineering of High-Stress Silicon Nitride Nanobeams.

    Science.gov (United States)

    Ghadimi, Amir Hossein; Wilson, Dalziel Joseph; Kippenberg, Tobias J

    2017-06-14

    High-stress Si3N4 nanoresonators have become an attractive choice for electro- and optomechanical devices. Membrane resonators can achieve quality factor (Q)-frequency (f) products exceeding 1013 Hz, enabling (in principle) quantum coherent operation at room temperature. String-like beam resonators possess smaller Q × f products; however, on account of their significantly lower mass and mode density, they remain a canonical choice for precision force, mass, and charge sensing, and have recently enabled Heisenberg-limited position measurements at cryogenic temperatures. Here we explore two techniques to enhance the Q of a nanomechanical beam. The techniques relate to two main loss mechanisms: internal loss, which dominates for high aspect ratios and f ≲ 100 MHz, and radiation loss, which dominates for low aspect ratios and f ≳ 100 MHz. First, we show that by embedding a nanobeam in a 1D phononic crystal (PnC), it is possible to localize its flexural motion and shield it against radiation loss. Using this method, we realize f > 100 MHz modes with Q ≈ 104, consistent with internal loss and contrasting sharply with unshielded beams of similar dimensions. We then study the Q × f product of high-order modes of millimeter-long nanobeams. Taking advantage of the mode-shape dependence of stress-induced "loss dilution", we realize a f ≈ 4 MHz mode with Q × f ≈ 9 × 1012 Hz. Our results complement recent work on PnC-based "soft-clamping" of nanomembranes, in which mode localization is used to enhance loss dilution. Combining these strategies should enable ultra-low-mass nanobeam oscillators that operate deep in the quantum coherent regime at room temperature.

  4. Measurement of different types of optical loss using high-precision laser photometer

    Science.gov (United States)

    Cao, Zhen; Hu, Guohang; He, Hongbo; Zhao, Yuanan; Wang, Yueliang; Peng, Xiaocong

    2017-06-01

    The development of high-power laser systems requires optical components that function at peak performance. Here, a high-precision, double beam, 1064 nm laser photometer setup was developed to measure the following different forms of optical loss from Nd-glass samples: total loss, volume loss, and the residual reflection and surface loss. The double beam design and a lock-in technique were utilized to decrease the impact of light-source instabilities and signal noise, respectively. The stability of the signal was further improved by decreasing the amount of optical absorption along the light path and by increasing the detection responsivity. Paired samples were symmetrically placed to eliminate beam displacement, and a laser scattering imaging technique was used to determine the influence of surface defects on the optical performance. Using the above techniques, multiple measurements of the transmittance and reflection values of the sample were taken, which showed our transmittance measurement to be highly precise, exhibiting a relative standard deviation of less than 0.06%. Different types of optical loss were distinguished and obtained from the transmittance and reflection measurements of samples with different thicknesses. A comparison of the optical performance from test points with and without surface defects allowed us to determine the influence of surface defects on the optical performance.

  5. Corrosion of Alloy 617 in high-temperature gas environments

    Energy Technology Data Exchange (ETDEWEB)

    Yeh, Tsung-Kuang [Institute of Nuclear Engineering and Science, National Tsing Hua University, Hsinchu 300, Taiwan (China); Department of Engineering and System Science, National Tsing Hua University, Hsinchu 300, Taiwan (China); Chang, Hao-Ping [Institute of Nuclear Engineering and Science, National Tsing Hua University, Hsinchu 300, Taiwan (China); Wang, Mei-Ya, E-mail: meywang@mx.nthu.edu.tw [Nuclear Science and Technology Development Center, National Tsing Hua University, Hsinchu 300, Taiwan (China); Yuan, Trai [Institute of Nuclear Engineering and Science, National Tsing Hua University, Hsinchu 300, Taiwan (China); Kai, Ji-Jung [Institute of Nuclear Engineering and Science, National Tsing Hua University, Hsinchu 300, Taiwan (China); Department of Engineering and System Science, National Tsing Hua University, Hsinchu 300, Taiwan (China)

    2014-05-01

    High-temperature gas-cooled reactors (HTGRs) with helium gas as the primary coolant have been considered as one type of the Generation IV nuclear power reactor systems. Several nickel-based superalloys, including Alloy 617, are potential structural materials to serve as pressure boundary components, such as the intermediate heat exchanger (IHX) in an HTGR. Impurities in a helium coolant, such as H{sub 2}O and O{sub 2}, can interact with structural materials at working temperatures of >900 °C, leading to serious degradation on these materials. In addition, defects in IHX surface coatings would allow these species to reach and interact with the external surfaces of these components, leading to similar or even more serious degradation. In this study we investigated the oxidation behavior of Alloy 617 in high-temperature, gaseous environments with various levels of O{sub 2} and H{sub 2}O. A series of general corrosion tests were conducted at test temperatures of 650 °C, 750 °C, 850 °C and 950 °C under various coolant compositions of dry air, 1% O{sub 2}, 10% relative humidity (RH), and 50% RH. Preliminary results showed that the surface morphologies of the Alloy 617 samples exhibited distinct evidence of intergranular corrosion. Compact chromium oxide layers were observed on the sample surfaces. The oxidation mechanisms of this alloy in the designated environments are discussed.

  6. Silicon Sensors for Trackers at High-Luminosity Environment

    CERN Document Server

    Peltola, Timo

    2015-01-01

    The planned upgrade of the LHC accelerator at CERN, namely the high luminosity (HL) phase of the LHC (HL-LHC foreseen for 2023), will result in a more intense radiation environment than the present tracking system was designed for. The required upgrade of the all-silicon central trackers at the ALICE, ATLAS, CMS and LHCb experiments will include higher granularity and radiation hard sensors. The radiation hardness of the new sensors must be roughly an order of magnitude higher than the one of LHC detectors. To address this, a massive R&D program is underway within the CERN RD50 collaboration "Development of Radiation Hard Semiconductor Devices for Very High Luminosity Colliders" to develop silicon sensors with sufficient radiation tolerance. Research topics include the improvement of the intrinsic radiation tolerance of the sensor material and novel detector designs with benefits like reduced trapping probability (thinned and 3D sensors), maximized sensitive area (active edge sensors) and enhanced charge ...

  7. Adaptation of an epilithic ecosystem to harsh high altitude environment

    Science.gov (United States)

    de La Torre Noetzel, R.; Horneck, G.; García Sancho, L.; Scherer, K.; Facius, R.; Urlings, T.; Rettberg, P.; Reina, M.; Pintado, A.

    2003-04-01

    Epilithic ecosystems in high mountains are exposed to an extreme microclimate characterized by intense solar UV radiation, high temperature fluctuations and high aridity. Using the epilithic ecosystem Rhizocarpon geographicum, the most abundant lichen at the Plataforma de Gredos (Sierra de Gredos, Central Spain, 1.895 m a.s.l.) as model system, we have investigated whether the cortex protects the photobiont against impacts by this extreme environment. The UV radiation climate was measured optoelectronically as well by use of the biological dosimeter DLR-Biofilm, and the microclimate (temperature, relative humidity, PAR) by a microclimatic station (Squirrel, U.K.). The photosynthetic activity of the lichens was periodically determined by use of a photosynthesis yield analyser MINI PAM. Using lichen samples with- and without cortex during different periods of a growing season, showed a substantial protection by the cortex against environmental stress conditions, especially at summer solstice. Solar UV radiation and desiccation exerted the most damaging effects in lichens without cortex. Because of the high resistance of the intact lichen against the harsh high altitude climate, R. geographicum has been selected as test system for survival studies in space to be performed during the upcoming BIOPAN mission of ESA.

  8. A new soft dielectric silicone elastomer matrix with high mechanical integrity and low losses

    DEFF Research Database (Denmark)

    Madsen, Frederikke Bahrt; Yu, Liyun; Daugaard, Anders Egede

    2015-01-01

    Though dielectric elastomers (DEs) have many favourable properties, the issue of high driving voltages limits the commercial viability of the technology. Driving voltage can be lowered by decreasing the Young's modulus and increasing the dielectric permittivity of silicone elastomers. A decrease...... in Young's modulus, however, is often accompanied by the loss of mechanical stability and thereby the lifetime of the DE. A new soft elastomer matrix, with no loss of mechanical stability and high dielectric permittivity, was prepared through the use of alkyl chloride-functional siloxane copolymers....... Furthermore, the increase in dielectric permittivity (43%) was obtained without compromising other important properties of DEs such as viscous and dielectric losses as well as electrical breakdown strength....

  9. A Longitudinal Investigation of the Home Literacy Environment and Shared Book Reading in Young Children With Hearing Loss.

    Science.gov (United States)

    DesJardin, Jean L; Stika, Carren J; Eisenberg, Laurie S; Johnson, Karen C; Hammes Ganguly, Dianne M; Henning, Shirley C; Colson, Bethany G

    The principle goal of this longitudinal study was to examine parent perceptions of home literacy environment (e.g., frequency of book reading, ease of book reading with child) and observed behaviors during shared book reading (SBR) interactions between parents and their children with hearing loss (HL) as compared with parents and their children with normal hearing (NH) across 3 time points (12, 24, and 36 months old). Relationships were also explored among home literacy environment factors and SBR behaviors and later language outcomes, across all three time points for parents of children with and without HL. Participants were a group of parents and their children with HL (N = 17) and typically developing children with NH (N = 34). Parent perceptions about the home literacy environment were captured through a questionnaire. Observed parent behaviors and their use of facilitative language techniques were coded during videotaped SBR interactions. Children's oral language skills were assessed using a standardized language measure at each time point. No significant differences emerged between groups of parents (HL and NH) in terms of perceived home literacy environment at 12 and 36 months. However, significant group differences were evident for parent perceived ease of reading to their child at 24 months. Group differences also emerged for parental SBR behaviors for literacy strategies and interactive reading at 12 months and for engagement and interactive reading at 36 months, with parents of children with HL scoring lower in all factors. No significant relationships emerged between early home literacy factors and SBR behaviors at 12 months and oral language skills at 36 months for parents of children with NH. However, significant positive relationships were evident between early home literacy environment factors at 12 months and oral language skills at 36 months for parents and their children with HL. Although both groups of parents increased their frequency of SBR

  10. High-frequency audiometry: a means for early diagnosis of noise-induced hearing loss.

    Science.gov (United States)

    Mehrparvar, Amir H; Mirmohammadi, Seyyed J; Ghoreyshi, Abbas; Mollasadeghi, Abolfazl; Loukzadeh, Ziba

    2011-01-01

    Noise-induced hearing loss (NIHL), an irreversible disorder, is a common problem in industrial settings. Early diagnosis of NIHL can help prevent the progression of hearing loss, especially in speech frequencies. For early diagnosis of NIHL, audiometry is performed routinely in conventional frequencies. We designed this study to compare the effect of noise on high-frequency audiometry (HFA) and conventional audiometry. In a historical cohort study, we compared hearing threshold and prevalence of hearing loss in conventional and high frequencies of audiometry among textile workers divided into two groups: With and without exposure to noise more than 85 dB. The highest hearing threshold was observed at 4000 Hz, 6000 Hz and 16000 Hz in conventional right ear audiometry, conventional left ear audiometry and HFA in each ear, respectively. The hearing threshold was significantly higher at 16000 Hz compared to 4000. Hearing loss was more common in HFA than conventional audiometry. HFA is more sensitive to detect NIHL than conventional audiometry. It can be useful for early diagnosis of hearing sensitivity to noise, and thus preventing hearing loss in lower frequencies especially speech frequencies.

  11. Whole high-quality light environment for humans and plants

    Science.gov (United States)

    Sharakshane, Anton

    2017-11-01

    Plants sharing a single light environment on a spaceship with a human being and bearing a decorative function should look as natural and attractive as possible. And consequently they can be illuminated only with white light with a high color rendering index. Can lighting optimized for a human eye be effective and appropriate for plants? Spectrum-based effects have been compared under artificial lighting of plants by high-pressure sodium lamps and general-purpose white LEDs. It has been shown that for the survey sample phytochrome photo-equilibria does not depend significantly on the parameters of white LED light, while the share of phytoactive blue light grows significantly as the color temperature increases. It has been revealed that yield photon flux is proportional to luminous efficacy and increases as the color temperature decreases, general color rendering index Ra and the special color rendering index R14 (green leaf) increase. General-purpose white LED lamps with a color temperature of 2700 K, Ra > 90 and luminous efficacy of 100 lm/W are as efficient as the best high-pressure sodium lamps, and at a higher luminous efficacy their yield photon flux per joule is even bigger in proportion. Here we show that demand for high color rendering white LED light is not contradictory to the agro-technical objectives.

  12. Whole high-quality light environment for humans and plants.

    Science.gov (United States)

    Sharakshane, Anton

    2017-11-01

    Plants sharing a single light environment on a spaceship with a human being and bearing a decorative function should look as natural and attractive as possible. And consequently they can be illuminated only with white light with a high color rendering index. Can lighting optimized for a human eye be effective and appropriate for plants? Spectrum-based effects have been compared under artificial lighting of plants by high-pressure sodium lamps and general-purpose white LEDs. It has been shown that for the survey sample phytochrome photo-equilibria does not depend significantly on the parameters of white LED light, while the share of phytoactive blue light grows significantly as the color temperature increases. It has been revealed that yield photon flux is proportional to luminous efficacy and increases as the color temperature decreases, general color rendering index Ra and the special color rendering index R14 (green leaf) increase. General-purpose white LED lamps with a color temperature of 2700 K, Ra > 90 and luminous efficacy of 100 lm/W are as efficient as the best high-pressure sodium lamps, and at a higher luminous efficacy their yield photon flux per joule is even bigger in proportion. Here we show that demand for high color rendering white LED light is not contradictory to the agro-technical objectives. Copyright © 2017. Published by Elsevier Ltd.

  13. High CpG island methylation of p16 gene and loss of p16 protein ...

    Indian Academy of Sciences (India)

    ... in p16 promoters in ToF patients was negatively correlated with p16 protein and gene expression (both P < 0.05). Our study reports that high CpG island methylation of p16 gene and loss of p16 protein expression associate with the development and progression of ToF, which may have significant therapeutic applications ...

  14. Thermal loss and soldering effect study of high-Q antennas in handheld devices

    DEFF Research Database (Denmark)

    Bahramzy, Pevand; Jagielski, Ole; Pedersen, Gert Frølund

    2013-01-01

    High-Q antennas are attractive because, besides being narrow-band, they have the advantage of being more compact and therefore occupy less volume in a mobile device. However, they can become very lossy especially at lower frequencies. In this paper it is investigated how low a thermal loss...

  15. Galaxy Merger Candidates in High-redshift Cluster Environments

    Science.gov (United States)

    Delahaye, A. G.; Webb, T. M. A.; Nantais, J.; DeGroot, A.; Wilson, G.; Muzzin, A.; Yee, H. K. C.; Foltz, R.; Noble, A. G.; Demarco, R.; Tudorica, A.; Cooper, M. C.; Lidman, C.; Perlmutter, S.; Hayden, B.; Boone, K.; Surace, J.

    2017-07-01

    We compile a sample of spectroscopically and photometrically selected cluster galaxies from four high-redshift galaxy clusters (1.59Red-Sequence Cluster Survey (SpARCS), and a comparison field sample selected from the UKIDSS Deep Survey. Using near-infrared imaging from the Hubble Space Telescope, we classify potential mergers involving massive ({M}* ≥slant 3× {10}10 {M}⊙ ) cluster members by eye, based on morphological properties such as tidal distortions, double nuclei, and projected near neighbors within 20 kpc. With a catalog of 23 spectroscopic and 32 photometric massive cluster members across the four clusters and 65 spectroscopic and 26 photometric comparable field galaxies, we find that after taking into account contamination from interlopers, {11.0}-5.6+7.0 % of the cluster members are involved in potential mergers, compared to {24.7}-4.6+5.3 % of the field galaxies. We see no evidence of merger enhancement in the central cluster environment with respect to the field, suggesting that galaxy-galaxy merging is not a stronger source of galaxy evolution in cluster environments compared to the field at these redshifts.

  16. An MWPC readout chip for high rate environment

    CERN Document Server

    Kano, H; Ikeno, M; Sasaki, O; Sato, K; Matsuura, S

    2000-01-01

    An ASIC has been fabricated in order to readout data from an MWPC that is installed in high rate environment. 16 channels and an ancillary control circuit are packed in a chip, and a channel consists of LVDS Receiver and 100-stage shift register array for delay. A hit data from the chamber is once input in the shift register array, and is just output from it when the trigger signal is set. If a channel contains a signal during a gate followed by the trigger, the channel is regarded to contain a hit. The primary purpose to construct the chip is for test beam and cosmic ray test of ATLAS thin gap chambers (TGC), which are used for the muon trigger signal generation. The architecture of the ASIC is so simple and uidependent from the specific readout scheme of ATLAS TGC. It will be found that the ASIC is adopted easily for any readout scheme of MWPC like detector. 3 Refs.

  17. Towards high-speed autonomous navigation of unknown environments

    Science.gov (United States)

    Richter, Charles; Roy, Nicholas

    2015-05-01

    In this paper, we summarize recent research enabling high-speed navigation in unknown environments for dynamic robots that perceive the world through onboard sensors. Many existing solutions to this problem guarantee safety by making the conservative assumption that any unknown portion of the map may contain an obstacle, and therefore constrain planned motions to lie entirely within known free space. In this work, we observe that safety constraints may significantly limit performance and that faster navigation is possible if the planner reasons about collision with unobserved obstacles probabilistically. Our overall approach is to use machine learning to approximate the expected costs of collision using the current state of the map and the planned trajectory. Our contribution is to demonstrate fast but safe planning using a learned function to predict future collision probabilities.

  18. High Molecular Weight Petrogenic and Pyrogenic Hydrocarbons in Aquatic Environments

    Science.gov (United States)

    Abrajano, T. A., Jr.; Yan, B.; O'Malley, V.

    2003-12-01

    Geochemistry is ultimately the study of sources, movement, and fate of chemicals in the geosphere at various spatial and temporal scales. Environmental organic geochemistry focuses such studies on organic compounds of toxicological and ecological concern (e.g., Schwarzenbach et al., 1993, 1998; Eganhouse, 1997). This field emphasizes not only those compounds with potential toxicological properties, but also the geological systems accessible to the biological receptors of those hazards. Hence, the examples presented in this chapter focus on hydrocarbons with known health and ecological concern in accessible shallow, primarily aquatic, environments.Modern society depends on oil for energy and a variety of other daily needs, with present mineral oil consumption throughout the 1990s exceeding 3×109 t yr-1 (NRC, 2002). In the USA, e.g., ˜40% of energy consumed and 97% of transportation fuels are derived from oil. In the process of extraction, refinement, transport, use, and waste production, a small but environmentally significant fraction of raw oil materials, processed products, and waste are released inadvertently or purposefully into the environment. Because their presence and concentration in the shallow environments are often the result of human activities, these organic materials are generally referred to as "environmental contaminants." Although such reference connotes some form of toxicological or ecological hazard, specific health or ecological effects of many organic "environmental contaminants" remain to be demonstrated. Some are, in fact, likely innocuous at the levels that they are found in many systems, and simply adds to the milieu of biogenic organic compounds that naturally cycle through the shallow environment. Indeed, virtually all compounds in crude oil and processed petroleum products have been introduced naturally to the shallow environments as oil and gas seepage for millions of years ( NRC, 2002). Even high molecular weight (HMW) polyaromatic

  19. High-dose tranexamic acid reduces intraoperative and postoperative blood loss in posterior lumbar interbody fusion.

    Science.gov (United States)

    Kushioka, Junichi; Yamashita, Tomoya; Okuda, Shinya; Maeno, Takafumi; Matsumoto, Tomiya; Yamasaki, Ryoji; Iwasaki, Motoki

    2017-03-01

    OBJECTIVE Tranexamic acid (TXA), a synthetic antifibrinolytic drug, has been reported to reduce blood loss in orthopedic surgery, but there have been few reports of its use in spine surgery. Previous studies included limitations in terms of different TXA dose regimens, different levels and numbers of fused segments, and different surgical techniques. Therefore, the authors decided to strictly limit TXA dose regimens, surgical techniques, and fused segments in this study. There have been no reports of using TXA for prevention of intraoperative and postoperative blood loss in posterior lumbar interbody fusion (PLIF). The purpose of the study was to evaluate the efficacy of high-dose TXA in reducing blood loss and its safety during single-level PLIF. METHODS The study was a nonrandomized, case-controlled trial. Sixty consecutive patients underwent single-level PLIF at a single institution. The first 30 patients did not receive TXA. The next 30 patients received 2000 mg of intravenous TXA 15 minutes before the skin incision was performed and received the same dose again 16 hours after the surgery. Intra- and postoperative blood loss was compared between the groups. RESULTS There were no statistically significant differences in preoperative parameters of age, sex, body mass index, preoperative diagnosis, or operating time. The TXA group experienced significantly less intraoperative blood loss (mean 253 ml) compared with the control group (mean 415 ml; p < 0.01). The TXA group also had significantly less postoperative blood loss over 40 hours (mean 321 ml) compared with the control group (mean 668 ml; p < 0.01). Total blood loss in the TXA group (mean 574 ml) was significantly lower than in the control group (mean 1080 ml; p < 0.01). From 2 hours to 40 hours, postoperative blood loss in the TXA group was consistently significantly lower. There were no perioperative complications, including thromboembolic events. CONCLUSIONS High-dose TXA significantly reduced both intra

  20. A Proposed Treatment for Visual Field Loss caused by Traumatic Brain Injury using Interactive Visuotactile Virtual Environment

    Science.gov (United States)

    Farkas, Attila J.; Hajnal, Alen; Shiratuddin, Mohd F.; Szatmary, Gabriella

    In this paper, we propose a novel approach of using interactive virtual environment technology in Vision Restoration Therapy caused by Traumatic Brain Injury. We called the new system Interactive Visuotactile Virtual Environment and it holds a promise of expanding the scope of already existing rehabilitation techniques. Traditional vision rehabilitation methods are based on passive psychophysical training procedures, and can last up to six months before any modest improvements can be seen in patients. A highly immersive and interactive virtual environment will allow the patient to practice everyday activities such as object identification and object manipulation through the use 3D motion sensoring handheld devices such data glove or the Nintendo Wiimote. Employing both perceptual and action components in the training procedures holds the promise of more efficient sensorimotor rehabilitation. Increased stimulation of visual and sensorimotor areas of the brain should facilitate a comprehensive recovery of visuomotor function by exploiting the plasticity of the central nervous system. Integrated with a motion tracking system and an eye tracking device, the interactive virtual environment allows for the creation and manipulation of a wide variety of stimuli, as well as real-time recording of hand-, eye- and body movements and coordination. The goal of the project is to design a cost-effective and efficient vision restoration system.

  1. Electromagnetic losses in a three-phase high temperature superconducting cable determined by calorimetric measurements

    DEFF Research Database (Denmark)

    Traeholt, C.; Veje, E.; Tønnesen, Ole

    2002-01-01

    A 10 m long high temperature superconducting (HTS) cable conductor was placed in a plane three-phase arrangement. The test-bed enabled us to study the conductor losses for different separations between the phases. The superconductor was fixed symmetrically in the centre, whilst the two outer...... conventional phases (600 mm2 Cu) could be moved in the plane. It was possible to vary the inter-phase distance (centre to centre distance) from 9 to 48 cm. The HTS cable conductor was placed in a stainless steel cryostat and cooled with flowing liquid nitrogen (LN2). The losses were determined using...... a calorimetric technique where the temperature increase in the flowing LN2 was measured with a set of thermo-couples. Results indicate that the total AC loss increases significantly when the separation between the conductors is reduced....

  2. Loss-less Nano-fractionator for High Sensitivity, High Coverage Proteomics

    DEFF Research Database (Denmark)

    Kulak, Nils A; Geyer, Philipp E; Mann, Matthias

    2017-01-01

    to be particularly powerful. This first dimension is typically performed with milliliter/min flow and relatively large column inner diameters, which allow efficient pre-fractionation but typically require peptide amounts in the milligram range. Here, we describe a novel approach termed "spider fractionator" in which...... more rapid or for extremely deep measurements. We demonstrate excellent sensitivity by decreasing sample amounts from 100 μg into the sub-microgram range, without losses attributable to the spider fractionator and while quantifying close to 10,000 proteins. Finally, we apply the system to the rapid...

  3. Flexible sample environment for high resolution neutron imaging at high temperatures in controlled atmosphere

    DEFF Research Database (Denmark)

    Makowska, Malgorzata G.; Kuhn, Luise Theil; Cleemann, Lars Nilausen

    2015-01-01

    with any other technique. This paper presents a new sample environment for in situ high resolution neutron imaging experiments at temperatures from room temperature up to 1100 ◦C and/or using controllable flow of reactive atmospheres. The design also offers the possibility to directly combine imaging......High material penetration by neutrons allows for experiments using sophisticated sample environments providing complex conditions. Thus, neutron imaging holds potential for performing in situ nondestructive measurements on large samples or even full technological systems, which are not possible...

  4. Estimation of power losses in a high-frequency planar transformer using a thermal camera

    Directory of Open Access Journals (Sweden)

    Barlik Roman

    2016-09-01

    Full Text Available This paper presents the implementation of a thermal camera for the quantitative estimation of power losses in a high frequency planar transformer (100 kHz/ 5600 VA. The methodology is based on the observation of the transient temperature rise and determination of the power losses by means of curves representing the derivative of temperature as a function of power losses dissipated in the transformer. First, the thermal calibration characteristics had to be obtained from a simple experiment, where power losses are generated by DC current in the ferrite core and windings. Next, experimental investigations focused on the determination of the transformer power losses for a short circuit and no load, with a resistive load and with the rectifier as a load were carried out. Finally, to verify the obtained results, analytical calculations based on Dowell’s and modified Steinmetz’s equations were additionally made, which showed a good convergence. The proposed method is easy to implement and can be used as an alternative to the calorimetric method which is time-consuming and requires a complicated measurement setup.

  5. Impact of Loss Synchronization on Reliable High Speed Networks: A Model Based Simulation

    Directory of Open Access Journals (Sweden)

    Suman Kumar

    2014-01-01

    Full Text Available Contemporary nature of network evolution demands for simulation models which are flexible, scalable, and easily implementable. In this paper, we propose a fluid based model for performance analysis of reliable high speed networks. In particular, this paper aims to study the dynamic relationship between congestion control algorithms and queue management schemes, in order to develop a better understanding of the causal linkages between the two. We propose a loss synchronization module which is user configurable. We validate our model through simulations under controlled settings. Also, we present a performance analysis to provide insights into two important issues concerning 10 Gbps high speed networks: (i impact of bottleneck buffer size on the performance of 10 Gbps high speed network and (ii impact of level of loss synchronization on link utilization-fairness tradeoffs. The practical impact of the proposed work is to provide design guidelines along with a powerful simulation tool to protocol designers and network developers.

  6. Factors related to high-level mobility in male servicemembers with traumatic lower-limb loss.

    Science.gov (United States)

    Gaunaurd, Ignacio A; Roach, Kathryn E; Raya, Michele A; Hooper, Rebecca; Linberg, Alison A; Laferrier, Justin Z; Campbell, Stuart M; Scoville, Charles; Gailey, Robert S

    2013-01-01

    The purpose of this study was to examine the possible relationship between factors modifiable by rehabilitation interventions (rehabilitation factors), other factors related to lower-limb loss (other factors), and high-level mobility as measured by the Comprehensive High-Level Activity Mobility Predictor (CHAMP) in servicemembers (SMs) with traumatic lower-limb loss. One-hundred eighteen male SMs with either unilateral transtibial amputation (TTA), unilateral transfemoral amputation (TFA), or bilateral lower-limb amputation (BLLA) participated. Stepwise regression analysis was used to develop separate regression models of factors predicting CHAMP score. Regression models containing both rehabilitation factors and other factors explained 81% (TTA), 36% (TFA), and 91% (BLLA) of the variance in CHAMP score. Rehabilitation factors such as lower-limb strength and dynamic balance were found to be significantly related to CHAMP score and can be enhanced with the appropriate intervention. Further, the findings support the importance of salvaging the knee joint and its effect on high-level mobility capabilities. Lastly, the J-shaped energy storage and return feet were found to improve high-level mobility for SMs with TTA. These results could help guide rehabilitation and aid in developing appropriate interventions to assist in maximizing high-level mobility capabilities for SMs with traumatic lower-limb loss.

  7. Occupational Noise Exposure, Bilateral High-Frequency Hearing Loss, and Blood Pressure.

    Science.gov (United States)

    Gan, Wen Qi; Mannino, David M

    2017-11-13

    The aim of this study was to investigate the relationships between occupational noise exposure and blood pressure using self-reported occupational exposure and bilateral high-frequency hearing loss. This study included 4548 participants aged 20 to 69 years from the National Health and Nutrition Examination Survey 1999 to 2004. On the basis of self-reported exposure status, participants were divided into the current, former, or never exposed groups. Bilateral high-frequency hearing loss was defined as the average high-frequency hearing threshold at least 25 dB in both ears. The currently exposed participants had slightly increased diastolic blood pressure compared with those never exposed. Among previously exposed participants, those with bilateral high-frequency hearing loss had increased systolic blood pressure, heart rate, and the prevalence of hypertension compared with those with normal high-frequency hearing. Although there were some significant results, the evidence was not consistent to support the associations between occupational noise exposure and blood pressure.

  8. Motion Planning Under Uncertainty In Highly Deformable Environments.

    Science.gov (United States)

    Patil, Sachin; van den, Jur; Alterovitz, Berg Ron

    2011-06-01

    Many tasks in robot-assisted surgery, food handling, manufacturing, and other applications require planning and controlling the motions of manipulators or other devices that must interact with highly deformable objects. We present a unified approach for motion planning under uncertainty in deformable environments that maximizes probability of success by accounting for uncertainty in deformation models, noisy sensing, and unpredictable actuation. Unlike prior planners that assume deterministic deformations or treat deformations as a type of small perturbation, our method explicitly considers the uncertainty in large, time-dependent deformations. Our method requires a simulator of deformable objects but places no significant restrictions on the simulator used. We use a sampling-based motion planner in conjunction with the simulator to generate a set of candidate plans based on expected deformations. Our method then uses the simulator and optimal control to numerically estimate time-dependent state distributions based on uncertain parameters (e.g. deformable material properties or actuation errors). We then select the plan with the highest estimated probability of successfully avoiding obstacles and reaching the goal region. Using FEM-based simulation of deformable tissues, we demonstrate the ability of our method to generate high quality plans in two medical-inspired scenarios: (1) guiding bevel-tip steerable needles through slices of deformable tissue around obstacles for minimally invasive biopsies and drug-delivery, and (2) manipulating planar tissues to align interior points at desired coordinates for precision treatment.

  9. Changes in Skeletal Integrity and Marrow Adiposity during High-Fat Diet and after Weight Loss.

    Science.gov (United States)

    Scheller, Erica L; Khoury, Basma; Moller, Kayla L; Wee, Natalie K Y; Khandaker, Shaima; Kozloff, Kenneth M; Abrishami, Simin H; Zamarron, Brian F; Singer, Kanakadurga

    2016-01-01

    The prevalence of obesity has continued to rise over the past three decades leading to significant increases in obesity-related medical care costs from metabolic and non-metabolic sequelae. It is now clear that expansion of body fat leads to an increase in inflammation with systemic effects on metabolism. In mouse models of diet-induced obesity, there is also an expansion of bone marrow adipocytes. However, the persistence of these changes after weight loss has not been well described. The objective of this study was to investigate the impact of high-fat diet (HFD) and subsequent weight loss on skeletal parameters in C57Bl6/J mice. Male mice were given a normal chow diet (ND) or 60% HFD at 6 weeks of age for 12, 16, or 20 weeks. A third group of mice was put on HFD for 12 weeks and then on ND for 8 weeks to mimic weight loss. After these dietary challenges, the tibia and femur were removed and analyzed by micro computed-tomography for bone morphology. Decalcification followed by osmium staining was used to assess bone marrow adiposity, and mechanical testing was performed to assess bone strength. After 12, 16, or 20 weeks of HFD, mice had significant weight gain relative to controls. Body mass returned to normal after weight loss. Marrow adipose tissue (MAT) volume in the tibia increased after 16 weeks of HFD and persisted in the 20-week HFD group. Weight loss prevented HFD-induced MAT expansion. Trabecular bone volume fraction, mineral content, and number were decreased after 12, 16, or 20 weeks of HFD, relative to ND controls, with only partial recovery after weight loss. Mechanical testing demonstrated decreased fracture resistance after 20 weeks of HFD. Loss of mechanical integrity did not recover after weight loss. Our study demonstrates that HFD causes long-term, persistent changes in bone quality, despite prevention of marrow adipose tissue accumulation, as demonstrated through changes in bone morphology and mechanical strength in a mouse

  10. Adjusting to Hearing Loss during High School: Preparing Students for Successful Transition to Postsecondary Education or Training. Tipsheet

    Science.gov (United States)

    Brooks, Dianne

    2009-01-01

    Completion of postsecondary education frequently builds upon a student's successful academic and personal experience during high school. For students with hearing loss, healthy adjustment to hearing loss is a key lifelong developmental process. The vast majority (94%) of approximately 1.1 million K-12 students with hearing loss are educated in…

  11. Treatment of recurrent pregnancy loss by Levothyroxine in women with high Anti-TPO antibody.

    Science.gov (United States)

    Mosaddegh, Mohammad Hosein; Ghasemi, Nasrin; Jahaninejad, Tahere; Mohsenifar, Fatemeh; Aflatoonian, Abbas

    2012-07-01

    Recurrent pregnancy loss (RPL) is defined as two or more consecutive pregnancy losses before twenty weeks of gestation. It is caused by a variety of genetics and non-genetics factors. Thyroid autoimmunity could associate with pregnancy loss. To investigate the effectiveness of Levothyroxine in treatment of RPL in women with high auto-thyroid antibodies. In this observational cross sectional study, 900 women who had a history of recurrent pregnancy loss were studied. All women with high anti-TPO antibody without any other problems entered in this study. Levothyroxine was given to them two months before pregnancy till the end of pregnancy. The doses of levothyroxine were depended on the anti-TPO levels, which were decided by endocrinologist. Women followed for the results of pregnancies. The success rate of pregnancy in women with abnormal anti-TPO with Levothyroxine therapy was 82.85%. Mean of anti-TPO in women with treatment before taking medication was 488.35 and after that it was 123.35 UI/ml. This difference was significant (pTPO antibody. It decreased anti-TPO antibody levels after 2-3 months treatment.

  12. A guinea pig model of selective severe high-frequency hearing loss.

    Science.gov (United States)

    Havenith, Sarah; Klis, Sjaak F L; Versnel, Huib; Grolman, Wilko

    2013-10-01

    Using an appropriate dose of an aminoglycoside antibiotic cotreated with a loop diuretic a guinea pig model of high-frequency loss can be obtained mimicking cochlear implant candidates with low-frequency residual hearing. We examined the stability of this model over time. A well-established method to create an animal model for profound deafness is cotreatment with an aminoglycoside antibiotic and a loop diuretic. Recent data indicated that reduction of the aminoglycoside dose might yield selective high-frequency hearing loss. Such a model is relevant for studies related to hybrid cochlear implant devices, for example, with respect to preservation of residual hearing. Guinea pigs received an electrode for chronic recording of compound action potentials to tones to assess thresholds. They were treated with a coadministration of kanamycin (200 mg/kg) and furosemide (100 mg/kg), after which, the animals were sacrificed for histologic analysis at 2, 4, or 7 weeks. After 2 to 7 weeks threshold shifts were greater than 50 dB for 8 to 16 kHz in 15 of 17 animals, whereas threshold shifts at 2 kHz or lower were less than 50 dB in 13 animals. Major threshold shifts occurred the first 2 to 4 days; subsequently, some spontaneous recovery occurred and, after 2-3 weeks thresholds, remained stable. Inner hair cell loss still progressed between 2 and 4 weeks in the most basal cochlear region; thereafter, hair cell loss was stable. An appropriate animal model for selective severe high-frequency hearing loss was obtained, which is stable at 4 weeks after ototoxic treatment.

  13. Loss-less Nano-fractionator for High Sensitivity, High Coverage Proteomics

    DEFF Research Database (Denmark)

    Kulak, Nils A; Geyer, Philipp E; Mann, Matthias

    2017-01-01

    to be particularly powerful. This first dimension is typically performed with milliliter/min flow and relatively large column inner diameters, which allow efficient pre-fractionation but typically require peptide amounts in the milligram range. Here, we describe a novel approach termed "spider fractionator" in which...... the post-column flow of a nanobore chromatography system enters an eight-port flow-selector rotor valve. The valve switches the flow into different flow channels at constant time intervals, such as every 90 s. Each flow channel collects the fractions into autosampler vials of the LC-MS/MS system. Employing...... a freely configurable collection mechanism, samples are concatenated in a loss-less manner into 2-96 fractions, with efficient peak separation. The combination of eight fractions with 100 min gradients yields very deep coverage at reasonable measurement time, and other parameters can be chosen for even...

  14. MPO-type single-mode multi-fiber connector: Low-loss and high-return-loss intermateability of APC-MPO connectors

    Science.gov (United States)

    Satake, Toshiaki; Nagasawa, Shinji; Hughes, Mike; Lutz, Sharon

    2011-01-01

    The electrical communication laboratory of NTT started the research of MT (Mechanically Transferable) connector in early 1980s. The initial goal was to realize a multi-fiber connector which can repeat low loss, stable, reliable and low-cost connections of subscriber optical fiber cable networks for more than 20 years period in the field. We review the multi-fiber alignment design with two guide pins, and following several technical improvements toward the final MT connector used in the commercial telecommunication networks. And then, we review development histories to reach to the low-loss, high-return-loss and reliable APC-MPO (Angled Physical Contact Multi-fiber Push On) connectors introduced in NTT COs and in Verizon's FTTH (Fiber To The Home) networks. In the latter half, we propose the low-loss intermateability design for connectors made by different suppliers in order to enable mass introductions into large scale systems. In addition we also describe an accurate connector loss presumption method for different lots' ferrules based on the MT ferrule dimension data before assembling the connectors. We believe with a wide intermateability of APC-MPO connector will increase its use in the fields. The APC-MPO connector manufactured based on the proposed design had low insertion losses of less than 0.25 dB at the same level of simplex connectors and the higher level of return losses higher than 65 dB.

  15. High temperature antigen retrieval and loss of nuclear morphology: a comparison of microwave and autoclave techniques.

    Science.gov (United States)

    Hunt, N C; Attanoos, R; Jasani, B

    1996-01-01

    The use of high temperature antigen retrieval methods has been of major importance in increasing the diagnostic utility of immunocytochemistry. However, these techniques are not without their problems and in this report attention is drawn to a loss of nuclear morphological detail, including mitotic figures, following microwave antigen retrieval. This was not seen with an equivalent autoclave technique. This phenomenon was quantified using image analysis in a group of B cell lymphomas stained with the antibody L26. Loss of nuclear morphological detail may lead to difficulty in identifying cells accurately, which is important in the diagnostic setting-for example, when trying to distinguish a malignant lymphoid infiltrate within a mixed cell population. In such cases it would clearly be wise to consider the use of alternative high temperature retrieval methods and accept their slightly lower staining enhancement capability compared with the microwave technique. Images PMID:9038766

  16. A simple method for reducing inevitable dielectric loss in high-permittivity dielectric elastomers

    DEFF Research Database (Denmark)

    Madsen, Frederikke Bahrt; Yu, Liyun; Mazurek, Piotr Stanislaw

    2016-01-01

    elastomer matrix, with high dielectric permittivity and a low Young's modulus, aligned with no loss of mechanical stability, was prepared through the use of commercially available chloropropyl-functional silicone oil mixed into a tough commercial liquid silicone rubber silicone elastomer. The addition......Commercial viability of dielectric elastomers (DEs) is currently limited by a few obstacles, including high driving voltages (in the kV range). Driving voltage can be lowered by either decreasing the Young's modulus or increasing the dielectric permittivity of silicone elastomers, or a combination...... of chloropropyl-functional silicone oil in concentrations up to 30 phr was found to improve the properties of the silicone elastomer significantly, as dielectric permittivity increased to 4.4, dielectric breakdown increased up to 25% and dielectric losses were reduced. The chloropropyl-functional silicone oil...

  17. Designing of highly birefringence, dispersion shifted decagonal photonic crystal fiber with low confinement loss

    Science.gov (United States)

    De, Moutusi; Gangwar, Rahul Kumar; Singh, Vinod Kumar

    2017-09-01

    In this article we propose a decagonal photonic crystal fiber (D-PCF) consisting unique cladding without structural complexity having very high birefringent of the order of 10-2, less effective area of few square microns as well as low confinement loss of the order of 10-2 dB/m at 1.55 μm wavelength. The zero dispersion wavelength is also achieved in the near infrared region. This study clearly attributes to the fact that the zero dispersion wavelength at the near infrared region, very high birefringence and low confinement loss can be adjusted according to the necessity by changing the structural parameters with considerable fabrication tolerance. This fiber can prove itself useful in laser technology, telecommunication, non-linear application, sensor technology and also in making polarization maintaining devices.

  18. High-Resolution Electron Energy-Loss Spectroscopy (HREELS) Using a Monochromated TEM/STEM

    Science.gov (United States)

    Sai, Z. R.; Bradley, J. P.; Erni, R.; Browning, N.

    2005-01-01

    A 200 keV FEI TF20 XT monochromated (scanning) transmission electron microscope funded by NASA's SRLIDAP program is undergoing installation at Lawrence Livermore National Laboratory. Instrument specifications in STEM mode are Cs =1.0 mm, Cc =1.2 mm, image resolution =0.18 nm, and in TEM mode Cs =1.3 mm, Cc =1.3 mm, information limit =0.14 nm. Key features of the instrument are a voltage-stabilized high tension (HT) supply, a monochromator, a high-resolution electron energy-loss spectrometer/energy filter, a high-resolution annular darkfield detector, and a solid-state x-ray energy-dispersive spectrometer. The high-tension tank contains additional sections for 60Hz and high frequency filtering, resulting in an operating voltage of 200 kV plus or minus 0.005V, a greater than 10-fold improvement over earlier systems. The monochromator is a single Wien filter design. The energy filter is a Gatan model 866 Tridiem-ERS high resolution GIF spec d for less than or equal to 0.15 eV energy resolution with 29 pA of current in a 2 nm diameter probe. 0.13 eV has already been achieved during early installation. The x-ray detector (EDAX/Genesis 4000) has a take-off angle of 20 degrees, an active area of 30 square millimeters, and a solid angle of 0.3 steradians. The higher solid angle is possible because the objective pole-piece allows the detector to be positioned as close as 9.47 mm from the specimen. The voltage-stabilized HT supply, monochromator and GIF enable high-resolution electron energy-loss spectroscopy (HREELS) with energy resolution comparable to synchrotron XANES, but with approximately 100X better spatial resolution. The region between 0 and 100 eV is called the low-loss or valence electron energy-loss spectroscopy (VEELS) region where features due to collective plasma oscillations and single electron transitions of valence electrons are observed. Most of the low-loss VEELS features we are detecting are being observed for the first time in IDPs. A major focus of

  19. The Mechanism of Burn-in Loss in a High Efficiency Polymer Solar Cell

    KAUST Repository

    Peters, Craig H.

    2011-10-11

    Degradation in a high efficiency polymer solar cell is caused by the formation of states in the bandgap. These states increase the energetic disorder in the system. The power conversion efficiency loss does not occur when current is run through the device in the dark but occurs when the active layer is photo-excited. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. The Effect of Heat Loss on Methane/Air Lean Premixed Combustion at High Pressure

    OpenAIRE

    瀬尾, 健彦; 澤中, 裕介; 林, 潤; 赤松, 史光; Takehiko, Seo; Yusuke, SAWANAKA; Jun, HAYASHI; Fumiteru, AKAMATSU; 東京工業大学大学院理工学研究科; 大阪大学大学院工学研究科; Department of Mechanical and Aerospace Engineering, Tokyo Institute of Technology; Department of Mechanical Engineering, Osaka University

    2008-01-01

    This study aimed to clarify the effect of the heat loss in the wall to the lean premixed combustion in a combustion chamber under high-pressure. Then, the interaction of the flame and the combustion chamber wall was changed by changing the ignition position in the combustion chamber. The flame propagation and pressure in the combustion chamber were measured. A thermodynamic analysis was done based on those results. As a result, the interaction with the flame and the wall obtained the influenc...

  1. Qualification of a Method to Calculate the Irrecoverable Pressure Loss in High Reynolds Number Piping Systems

    Energy Technology Data Exchange (ETDEWEB)

    Sigg, K. C.; Coffield, R. D.

    2002-09-01

    High Reynolds number test data has recently been reported for both single and multiple piping elbow design configurations at earlier ASME Fluid Engineering Division conferences. The data of these studies ranged up to a Reynolds number of 42 x 10[sup]6 which is significantly greater than that used to establish design correlations before the data was available. Many of the accepted design correlations, based on the lower Reynolds number data, date back as much as fifty years. The new data shows that these earlier correlations are extremely conservative for high Reynolds number applications. Based on the recent high Reynolds number information a new recommended method has been developed for calculating irrecoverable pressure loses in piping systems for design considerations such as establishing pump sizing requirements. This paper describes the recommended design approach and additional testing that has been performed as part of the qualification of the method. This qualification testing determined the irrecoverable pressure loss of a piping configuration that would typify a limiting piping section in a complicated piping network, i.e., multiple, tightly coupled, out-of-plane elbows in series under high Reynolds number flow conditions. The overall pressure loss measurements were then compared to predictions, which used the new methodology to assure that conservative estimates for the pressure loss (of the type used for pump sizing) were obtained. The recommended design methodology, the qualification testing and the comparison between the predictions and the test data are presented. A major conclusion of this study is that the recommended method for calculating irrecoverable pressure loss in piping systems is conservative yet significantly lower than predicted by early design correlations that were based on the extrapolation of low Reynolds number test data.

  2. When High Tech ceases to be High Growth: The Loss of Dynamism of the Cambridgeshire Regio

    NARCIS (Netherlands)

    Stam, E.|info:eu-repo/dai/nl/215649370; Martin, R.

    2012-01-01

    This paper analyses mechanisms of decline and renewal in high-tech regions, illustrated with empirical evidence on the Cambridgeshire high-tech region in the UK. The paper contributes to ecological (‘carrying capacity’) and evolutionary (path dependence) theories of regional development. It provides

  3. Multi-Language Programming Environments for High Performance Java Computing

    Directory of Open Access Journals (Sweden)

    Vladimir Getov

    1999-01-01

    Full Text Available Recent developments in processor capabilities, software tools, programming languages and programming paradigms have brought about new approaches to high performance computing. A steadfast component of this dynamic evolution has been the scientific community’s reliance on established scientific packages. As a consequence, programmers of high‐performance applications are reluctant to embrace evolving languages such as Java. This paper describes the Java‐to‐C Interface (JCI tool which provides application programmers wishing to use Java with immediate accessibility to existing scientific packages. The JCI tool also facilitates rapid development and reuse of existing code. These benefits are provided at minimal cost to the programmer. While beneficial to the programmer, the additional advantages of mixed‐language programming in terms of application performance and portability are addressed in detail within the context of this paper. In addition, we discuss how the JCI tool is complementing other ongoing projects such as IBM’s High‐Performance Compiler for Java (HPCJ and IceT’s metacomputing environment.

  4. Learning rate and temperament in a high predation risk environment

    Science.gov (United States)

    DePasquale, C.; Wagner, Tyler; Archard, G.A.; Ferguson, B.; Braithwaite, V.A.

    2014-01-01

    Living in challenging environments can influence the behavior of animals in a number of ways. For instance, populations of prey fish that experience frequent, nonlethal interactions with predators have a high proportion of individuals that express greater reaction to risk and increased activity and exploration—collectively known as temperament traits. Temperament traits are often correlated, such that individuals that are risk-prone also tend to be active and explore more. Spatial learning, which requires the integration of many sensory cues, has also been shown to vary in fish exposed to different levels of predation threat. Fish from areas of low predation risk learn to solve spatial tasks faster than fish from high predation areas. However, it is not yet known whether simpler forms of learning, such as learning associations between two events, are similarly influenced. Simple forms of associative learning are likely to be affected by temperament because a willingness to approach and explore novel situations could provide animals with a learning advantage. However, it is possible that routine-forming and inflexible traits associated with risk-prone and increased exploratory behavior may act in the opposite way and make risk-prone individuals poorer at learning associations. To investigate this, we measured temperament in Panamanian bishop fish (Brachyrhaphis episcopi) sampled from a site known to contain many predators. The B. episcopi were then tested with an associative learning task. Within this population, fish that explored more were faster at learning a cue that predicted access to food, indicating a link between temperament and basic learning abilities.

  5. Learning rate and temperament in a high predation risk environment.

    Science.gov (United States)

    DePasquale, C; Wagner, T; Archard, G A; Ferguson, B; Braithwaite, V A

    2014-11-01

    Living in challenging environments can influence the behavior of animals in a number of ways. For instance, populations of prey fish that experience frequent, nonlethal interactions with predators have a high proportion of individuals that express greater reaction to risk and increased activity and exploration-collectively known as temperament traits. Temperament traits are often correlated, such that individuals that are risk-prone also tend to be active and explore more. Spatial learning, which requires the integration of many sensory cues, has also been shown to vary in fish exposed to different levels of predation threat. Fish from areas of low predation risk learn to solve spatial tasks faster than fish from high predation areas. However, it is not yet known whether simpler forms of learning, such as learning associations between two events, are similarly influenced. Simple forms of associative learning are likely to be affected by temperament because a willingness to approach and explore novel situations could provide animals with a learning advantage. However, it is possible that routine-forming and inflexible traits associated with risk-prone and increased exploratory behavior may act in the opposite way and make risk-prone individuals poorer at learning associations. To investigate this, we measured temperament in Panamanian bishop fish (Brachyrhaphis episcopi) sampled from a site known to contain many predators. The B. episcopi were then tested with an associative learning task. Within this population, fish that explored more were faster at learning a cue that predicted access to food, indicating a link between temperament and basic learning abilities.

  6. High excitation rovibrational molecular analysis in warm environments

    Science.gov (United States)

    Zhang, Ziwei; Stancil, Phillip C.; Cumbee, Renata; Ferland, Gary J.

    2017-06-01

    Inspired by advances in infrared observation (e.g., Spitzer, Herschel and ALMA), we investigate rovibrational emission CO and SiO in warm astrophysical environments. With recent innovation in collisional rate coefficients and rescaling methods, we are able to construct more comprehensive collisional data with high rovibrational states (vibration up to v=5 and rotation up to J=40) and multiple colliders (H2, H and He). These comprehensive data sets are used in spectral simulations with the radiative transfer codes RADEX and Cloudy. We obtained line ratio diagnostic plots and line spectra for both near- and far-infrared emission lines over a broad range of density and temperature for the case of a uniform medium. Considering the importance of both molecules in probing conditions and activities of UV-irradiated interstellar gas, we model rovibrational emission in photodissociation region (PDR) and AGB star envelopes (such as VY Canis Majoris, IK Tau and IRC +10216) with Cloudy. Rotational diagrams, energy distribution diagrams, and spectra are produced to examine relative state abundances, line emission intensity, and other properties. With these diverse models, we expect to have a better understanding of PDRs and expand our scope in the chemical architecture and evolution of AGB stars and other UV-irradiated regions. The soon to be launched James Webb Space Telescope (JWST) will provide high resolution observations at near- to mid-infrared wavelengths, which opens a new window to study molecular vibrational emission calling for more detailed chemical modeling and comprehensive laboratory astrophysics data on more molecules. This work was partially supported by NASA grants NNX12AF42G and NNX15AI61G. We thank Benhui Yang, Kyle Walker, Robert Forrey, and N. Balakrishnan for collaborating on the collisional data adopted in the current work.

  7. High winds induce nitrogen loss from US Pacific Northwest agricultural lands

    Science.gov (United States)

    Sharratt, B. S.; Graves, L.; Pressley, S. N.

    2012-12-01

    High winds common to the Pacific Northwest region of the USA have resulted in massive loss of topsoil from agricultural fields that are primarily managed in a winter wheat / summer fallow rotation. This topsoil contains nitrogen (N), an essential nutrient required for growth and development of plants. Loss of N from soils can cause degradation of air and water quality and also is an economic concern to farmers because depletion of nutrients from soils results in lower crop yield. Flux of windblown sediment moving across eroding fields was measured during high wind events between 1999 and 2006 in eastern Washington. Samplers were deployed to trap sediment that was creeping along or in saltation/suspension at various heights above fields that were in the summer fallow phase of the rotation. Windblown sediment was weighed and analyzed for N content by combustion and a thermal conductivity analyzer. Enrichment, or the ratio of N in the windblown sediment to soil of greater than one, was observed in about half of the years. For nearly all high wind events, N content of sediment transported by creep was greater than sediment transported by saltation or suspension. This study suggests that wind erosion can result in loss of N from agricultural soils.

  8. A high parasite density environment induces transcriptional changes and cell death in Plasmodium falciparum blood stages.

    Science.gov (United States)

    Chou, Evelyn S; Abidi, Sabia Z; Teye, Marian; Leliwa-Sytek, Aleksandra; Rask, Thomas S; Cobbold, Simon A; Tonkin-Hill, Gerry Q; Subramaniam, Krishanthi S; Sexton, Anna E; Creek, Darren J; Daily, Johanna P; Duffy, Michael F; Day, Karen P

    2017-12-27

    Transient regulation of Plasmodium numbers below the density that induces fever has been observed in chronic malaria infections in humans. This species transcending control cannot be explained by immunity alone. Using an in vitro system we have observed density dependent regulation of malaria population size as a mechanism to possibly explain these in vivo observations. Specifically, Plasmodium falciparum blood stages from a high but not low-density environment exhibited unique phenotypic changes during the late trophozoite (LT) and schizont stages of the intraerythrocytic cycle. These included in order of appearance: failure of schizonts to mature and merozoites to replicate, apoptotic-like morphological changes including shrinking, loss of mitochondrial membrane potential, and blebbing with eventual release of aberrant parasites from infected erythrocytes. This unique death phenotype was triggered in a stage-specific manner by sensing of a high-density culture environment. Conditions of glucose starvation, nutrient depletion, and high lactate could not induce the phenotype. A high-density culture environment induced rapid global changes in the parasite transcriptome including differential expression of genes involved in cell remodeling, clonal antigenic variation, metabolism, and cell death pathways including an apoptosis-associated metacaspase gene. This transcriptional profile was also characterized by concomitant expression of asexual and sexual stage-specific genes. The data show strong evidence to support our hypothesis that density sensing exists in P. falciparum. They indicate that an apoptotic-like mechanism may play a role in P. falciparum density regulation, which, as in yeast, has features quite distinguishable from mammalian apoptosis. Gene expression data are available in the GEO databases under the accession number GSE91188. © 2017 Federation of European Biochemical Societies.

  9. High bit rate BPSK signals in shallow water environments

    NARCIS (Netherlands)

    Robert, M.K.; Walree, P.A. van

    2003-01-01

    Lately, acoustic data transfer has become an important topic in underwater environments. Several acoustic communication signals e.g. spread spectrum or frequency shift keying signals have been extensively developed. However, in challenging environments, it is still difficult to obtain robust

  10. Channel characterization in high-speed railway station environments at 1.89 GHz

    Science.gov (United States)

    Zhou, Tao; Tao, Cheng; Salous, Sana; Liu, Liu; Tan, Zhenhui

    2015-11-01

    Channel characterization is the prerequisite condition for the research and development of the next-generation high-speed railway (HSR) communication system. Train station is one of typical HSR scenarios, where channel characteristics have not yet been investigated sufficiently. In this paper, wideband multiantenna channel measurements are performed at 1.89 GHz in an open-type train station environment based on long-term evolution networks along Beijing to Tianjin HSR in China. Large-scale characteristics of the HSR station channel, focusing on path loss, shadow fading (SF), and the autocorrelation property of SF, are studied. Moreover, small-scale characteristics, such as Ricean K-factor, delay spread, and spatial correlation, are analyzed and modeled. In addition, the stationary region is characterized using the RUN test method. The obtained results provide useful information for deployment and assessment of the future HSR communication system in the HSR station scenario.

  11. Standard guide for corrosion tests in high temperature or high pressure environment, or both

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 This guide covers procedures, specimens, and equipment for conducting laboratory corrosion tests on metallic materials under conditions of high pressure (HP) or the combination of high temperature and high pressure (HTHP). See for definitions of high pressure and temperature. 1.2 Tests conducted under HP or HTHP by their nature have special requirements. This guide establishes the basic considerations that are necessary when these conditions must be incorporated into laboratory corrosion tests. 1.3 The procedures and methods in this guide are applicable for conducting mass loss corrosion, localized corrosion, and electrochemical tests as well as for use in environmentally induced cracking tests that need to be conducted under HP or HTHP conditions. 1.4 The primary purpose for this guide is to promote consistency of corrosion test results. Furthermore, this guide will aid in the comparison of corrosion data between laboratories or testing organizations that utilize different equipment. 1.5 The values s...

  12. Nuclear and Non-Ionizing Energy-Loss for Coulomb Scattered Particles from Low Energy up to Relativistic Regime in Space Radiation Environment

    CERN Document Server

    Boschini, M.J.; Gervasi, M.; Giani, S.; Grandi, D.; Ivantchenko, V.; Pensotti, S.; Rancoita, P.G.; Tacconi, M.

    2011-01-01

    In the space environment, instruments onboard of spacecrafts can be affected by displacement damage due to radiation. The differential scattering cross section for screened nucleus--nucleus interactions - i.e., including the effects due to screened Coulomb nuclear fields -, nuclear stopping powers and non-ionization energy losses are treated from about 50\\,keV/nucleon up to relativistic energies.

  13. Egyptian diatomite as high fluid loss squeeze slurry in sealing fractures and

    Directory of Open Access Journals (Sweden)

    A.M. Al-Sabagh

    2016-09-01

    Full Text Available Lost circulation is the most costly mud related drilling problem, and induced fracture. Water slurry of diatomite is used as the high fluid loss squeeze slurry in the treatment of lost circulation and in decreasing fluid loss. Egypt has diatomite deposits, especially in El-Fayuom Depression. Fourteen samples were collected from Qasr El-Sagha at the northern shore of Birket Qarun. Samples were examined to identify the diatom species then subjected to X-ray fluorescence, XRD and grain size distribution tests. A total of 38 species related to 13 diatom genera were identified. Cocconeis, Epithemia and Rhopalodia were the predominant genera. The diatomaceous earth which acts as a filter aid material was tested with different additives; bentonite, lime, finely divided paper, polymer, barite and different concentrations with different types of lost circulation materials (LCM to form a high fluid loss squeeze slurry. As a result the required time for collecting the filtrate was decreased to be in the range of 50 s to 1 min and 49 s comparing with the international standard which recommended the filtrate should be collected maximum within 2–3 min.

  14. Rankings of High School Sports Injury Rates Differ Based on Time Loss Assessments.

    Science.gov (United States)

    Kerr, Zachary Y; Roos, Karen G; Djoko, Aristarque; Dompier, Thomas P; Marshall, Stephen W

    2017-11-01

    To examine how injury definition inclusiveness affects the rank order of injury rates in 27 high school (HS) sports. The National Athletic Treatment, Injury and Outcomes Network (NATION) used certified athletic trainers (ATs) to collect injury and athlete-exposure (AE) data in practices and competitions for 27 HS sports during the 2011/2012 to 2013/2014 academic years. Time loss (TL) injuries resulted in ≥24 hours of participation restriction. Nontime loss (NTL) injuries resulted in sports. High school student-athletes. Sports injury data from the National Athletic Treatment, Injury and Outcomes Network. Time loss and TL + NTL injury rates were calculated. Sport-specific rates were placed in rank order, stratified by gender. Most of the 47 014 injuries reported were NTL (82.8%). Among boys' sports, TL injury rates were greatest in football (3.27/1000AE) and wrestling (2.43/1000AE); TL + NTL injury rates were greatest also in football (15.29/1000AE) and wrestling (11.62/1000AE). Among girls' sports, TL injury rates were greatest in soccer (1.97/1000AE) and basketball (1.76/1000AE); TL + NTL injury rates were greatest in field hockey and lacrosse (both 11.32/1000AE). The rank order of injury rates and the resulting injury prevention priorities may depend on injury definition inclusiveness, particularly in female HS sports.

  15. SRAM-Based Passive Dosimeter for High-Energy Accelerator Environments

    CERN Document Server

    Makowski, D R; Napieralski, A; Swiercz, B P

    2005-01-01

    This paper reports a novel NVRAM-based neutron dose monitor (REM counter). The principle of this device is based on the radiation effect initiating the Single Event Upset SEU in high density microelectronic memories. Several batches of Non-Volatile memories from different manufactures were examined in various radiation environments, i.e. 241Am-Be (alpha,n) and Linear accelerators produced radiation fields. A suitable moderator was used to enhance the detector sensitivity. Further experiments were carried out in Linear Accelerators: Linac II, TTF2 and Beam Loss Environment of various Experimental Facilities at DESY Research Centre in Hamburg. A separate batch of SRAM was irradiated with 60Co-gamma rays up to a dose of about 60 Gy. No Single Event Upset (SEU) was registered. This validates, that gamma radiation has a negligible effect to trigger SEU in the SRAM. The proposed detector could be ideal for a neutron dose measurement produced by a high-energy electron linac, including synchrotron and Free Electron L...

  16. New Oxide Materials for an Ultra High Temperature Environment

    Energy Technology Data Exchange (ETDEWEB)

    Perepezko, John H. [Univ. of Wisconsin, Madison, WI (United States). Dept. of Materials Science and Engineering

    2017-11-13

    In this project, a new oxide material, Hf6Ta2O17 has been successfully synthesized by the controlled oxidization of Hf-Ta alloys. This oxide exhibits good oxidation resistance, high temperature phase stability up to more than 2000°C, low thermal conductivity and thus could serve as a component or a coating material in an ultrahigh temperature environment. We have examined the microstructure evolution and phase formation sequence during the oxidation exposure of Hf-Ta alloys at 1500°C and identified that the oxidation of a Hf-26.7atomic %Ta alloy leads to the formation of a single phase adherent Hf6Ta2O17 with a complex atomic structure i.e. superstructure. The overall reactive diffusion pathway is consistent with the calculated Hf-Ta-O ternary phase diagram. Besides the synthesis of Hf6Ta2O17 superstructure by oxidizing Hf-Ta alloys, we have also developed a synthesis method based upon the reactive sintering of the correct ratios of mixed powders of HfO2 and Ta2O5 and verified the low thermal conductivity of Hf6Ta2O17 superstructure on these samples. We have completed a preliminary analysis of the oxidation kinetics for Hf6Ta2O17, which shows an initial parabolic oxidation kinetics.

  17. How sensitive are high-pt electron spectra at RHIC to heavy quark energy loss?

    CERN Document Server

    Armesto, N; Dainese, A; Salgado, C A; Wiedemann, Urs Achim

    2006-01-01

    In nucleus-nucleus collisions, high-pt electron spectra depend on the medium modified fragmentation of their massive quark parents, thus giving novel access to the predicted mass hierarchy of parton energy loss. Here we calculate these spectra in a model, which supplements the perturbative QCD factorization formalism with parton energy loss. In general, we find - within large errors - rough agreement between theory and data on the single inclusive electron spectrum in pp, its nuclear modification factor, and its azimuthal anisotropy. However, the nuclear modification factor depends on the relative contribution of charm and bottom production, which we find to be affected by large perturbative uncertainties. In order for electron measurements to provide a significantly more stringent test of the expected mass hierarchy, one must then disentangle the b- and c-decay contributions, for instance by reconstructing the displaced decay vertices.

  18. Counting losses due to saturation effects of scintillation counters at high count rates

    CERN Document Server

    Hashimoto, K

    1999-01-01

    The counting statistics of a scintillation counter, with a preamplifier saturated by an overloading input, are investigated. First, the formulae for the variance and the mean number of counts, accumulated within a given gating time, are derived by considering counting-loss effects originating from the saturation and a finite resolving time of the electronic circuit. Numerical examples based on the formulae indicate that the saturation makes a positive contribution to the variance-to-mean ratio and that the contribution increases with count rate. Next the ratios are measured under high count rates when the preamplifier saturation can be observed. By fitting the present formula to the measured data, the counting-loss parameters can be evaluated. Corrections based on the parameters are made for various count rates measured in a nuclear reactor. As a result of the corrections, the linearity between count rate and reactor power can be restored.

  19. Study of Acquisition Electronics with a High Dynamic Range for a Beam Loss Measurement System

    CERN Document Server

    Venturini, G; Dehning, B; Effinger, E

    2010-01-01

    The particles accelerated in CERN accelerator chain reach high energies, topped by the particle energy at collision in the LHC, 7 GeV. During the operation, an amount of particles is inevitably lost from the beam. Depending on the extent of the losses, physical damage to machine components may be caused and the shower of secondary emission particles deposits energy in the surrounding equipment constituting the accelerator. The hadronic cascade also activates their materials, representing a hazard to the workers at CERN. In the LHC, the superconducting magnets that constitute the synchrotron lattice are kept at an operating temperature of 1:9K through a cryogenic facility employing superliquid helium, the increase in their temperature potentially initiates a quench. In the SPS, the damage due to a lost beam is also visible. The Beam Loss Monitoring (BLM) system has been developed to reliably protect the machines composing CERN’s accelerator chain and additionally provide information about the beam status: th...

  20. Break-down of Losses in High Performing Metal-Supported Solid Oxide Fuel Cells

    DEFF Research Database (Denmark)

    Kromp, Alexander; Nielsen, Jimmi; Blennow Tullmar, Peter

    2012-01-01

    , the ohmic and polarization losses related to the gas diffusion in the metal support, the electrooxidation in the anode functional layer and the oxygen reduction in the mixed ionic electronic conducting cathode were determined. An additional process with a rather high relaxation frequency could be attributed...... present the results of performance and stability improvements for a metal supported cell developed within the European project METSOFC and the Danish National Advanced Technology Foundation. The cells consist of a porous metal backbone, a metal / zirconia cermet anode and a 10ScYSZ electrolyte, cofired...... in between cathode and electrolyte. The detailed electrochemical characterization by means of impedance spectroscopy and a subsequent data analysis by the distribution of relaxation times enabled us to separate the different loss contributions in the cell. Based on an appropriate equivalent circuit model...

  1. Interaction between diabetes mellitus and hypertension on risk of hearing loss in highly endogamous population.

    Science.gov (United States)

    Bener, Abdulbari; Al-Hamaq, Abdulla O A A; Abdulhadi, Khalid; Salahaldin, Ahmed H; Gansan, Loida

    2017-11-01

    The aim of this study was to determine the prevalence of hearing loss and its association with type 2 diabetes mellitus (T2DM) in a highly endogamous population. This is a cross-sectional study. The present study is carried out in Ear Nose Throat (ENT) and Endocrinology outpatient clinics of the Hamad General and Rumeilah Hospitals, Hamad Medical Corporation. All subjects aged between 20 and 59 years who visited the Endocrinology and ENT outpatient clinics of the Hamad Medical Corporation with hearing difficulty were included in this study during the period from January 2013 to July 2014. During the study period, prevalence, hearing, audiological test, family history and medical problems associated with hearing impairment in middle aged patients were recorded. Two audiometers Grason Stadler GSI 61 and Madsen Orbiter 922 were used to evaluate the hearing loss. Majority of the hearing loss observed at the age above 45 years old, (44.8% vs 51.7%, p=0.05). The prevalence of hearing impairment was higher in Qataris than in non-Qataris (59.7% vs 46.6%, pdiabetes onset duration (7.8±4.12years), sleeping disorder (5.81±1.29h), obese subjects (38% vs 27.4%); family history of diabetes (30.6 vs 23.1%) were higher among hearing impairment. The associated risk factors were significantly higher in T2DM with hearing loss, hypoglycemia (32.8% vs 27.4%), retinopathy (313% vs 18.5%), Nephropathy (17.9% vs 9.8%), Neuropathy (17.9% vs 10.2%), macro-vascular disease (11.9% vs 6.2%), diabetic foot ulcer (20.9% vs 12.6%), Tinnitus (68.7% vs 51.3%), and Vertigo (25.4% vs 16.9%) than in normal hearing diabetes. There was a statistically significant differences between hearing impairment and normal hearing among T2DM regarding hearing assessment frequency (p=0.041). There were statistically significant differences between hearing impairment versus normal hearing for vitamin D [18.91±7.65ng/mL vs 22.85±9.00ng/mL; pdiabetic patients. The current study results confirm previous reports

  2. Glass tube of high dielectric constant and low dielectric loss for external electrode fluorescent lamps

    Science.gov (United States)

    Cho, Guangsup; Shin, Myeong-Ju; Jeong, Jong-Mun; Kim, Jung-Hyun; Hong, Byoung-Hee; Koo, Je-Huan; Kim, YunKi; Choi, Eun-Ha; Fechner, Joerg; Letz, Martin; Ott, Franz

    2007-12-01

    A glass tube of aluminosilicate glass, with high dielectric constant K ˜6.0 and low dielectric loss tan δ˜8.0×10-4, was investigated for the external electrode fluorescent lamps (EEFLs) of a dielectric barrier discharge. Compared with conventional EEFLs made out of borosilicate glass tubes with K˜(4.9-5.3) and tan δ˜(2.3-2.4)×10-3, the efficiency of the aluminosilicate EEFL increases by 15%-25% even at high luminance above 20 000 cd/m2 and the pinhole stability of the aluminosilicate EEFL also improves remarkably. In a soda-lime glass EEFL with a high dielectric loss tan δ˜7.0×10-3, the luminance and pinhole stability deteriorate even with a high dielectric constant K ˜7.2 at room temperature, because the value of tan δ escalates as the temperature on the external electrode increases due to the dielectric heat dissipation.

  3. High fibrinogen in peripheral blood correlates with poorer hearing recovery in idiopathic sudden sensorineural hearing loss.

    Directory of Open Access Journals (Sweden)

    Sho Kanzaki

    Full Text Available OBJECTIVES: We used hearing tests and peripheral blood sample analyses to characterize the pathology of idiopathic sudden sensorineural hearing loss (ISSNHL and to identify possible prognostic factors for predicting recovery of hearing loss. STUDY DESIGN: A retrospective, multicenter trial was conducted. METHODS: Two hundred three patients examined within 7 days after the onset of ISSNHL received prednisone with lipo-prostaglandin E1. Pure-tone auditory tests were performed before and after treatment with these drugs. Blood tests were performed on blood samples collected during the patients' initial visit to our clinic. RESULTS: In all patients, elevated white blood cell (WBC counts, fasting blood sugar levels, HgbA1c, and erythrocyte sedimentation rate (ESR significantly correlated with high hearing threshold measurements obtained on the initial visit. High fibrinogen levels, WBC counts, ESR, and low concentrations of fibrinogen degradation products (FDP were associated with lower hearing recovery rates. Additionally, different audiogram shapes correlated with different blood test factors, indicating that different pathologies were involved. CONCLUSIONS: High fibrinogen levels measured within seven days after ISSNHL onset correlated with poorer hearing recovery. This may be a consequence of ischemia or infections in the inner ear. The high WBC counts also observed may therefore reflect an immune response to inner ear damage induced by ischemic changes or infections. Our data indicate that therapeutic strategies should be selected based on the timing of initial treatment relative to ISSNHL onset.

  4. Plasma pressure and particle loss studies in the Pilot-PSI high flux linear plasma generator

    Directory of Open Access Journals (Sweden)

    K. Ješko

    2017-08-01

    Full Text Available Plasma detachment in tokamak divertors reduces the particle and power fluxes to the plasma facing components and is essential for successful operation of ITER. The linear plasma generator Pilot-PSI can produce a high density (∼1021 m−3, low temperature (∼1eV plasma which is similar to that expected at the ITER divertor strike-points during the partially detached regime [1]. Given the simple geometry of the device, Pilot-PSI allows to diagnose the plasma beam at multiple axial positions. In this study, the incoherent Thomson scattering (TS diagnostic [2] is exploited to measure the radial plasma Te and ne profiles at two locations of the hydrogen plasma beam: near the plasma source (upstream and 2cm from the target plate. At the target, the TS measurements are supported by an embedded Langmuir probe. These measurements prove the existence of parallel plasma pressure loss as well as particle loss, confirming that physical processes believed to cause detachment in tokamak divertors also hold in Pilot-PSI (ion-neutral friction, volume recombination. It is found that the fractional reduction of the plasma pressure varies between ∼4 and ∼5000, depending strongly on the pressure of the background neutrals. The importance of individual loss channels is discussed.

  5. Edge loss of high-harmonic fast-wave heating power in NSTX: a cylindrical model

    Science.gov (United States)

    Perkins, R. J.; Hosea, J. C.; Bertelli, N.; Taylor, G.; Wilson, J. R.

    2017-11-01

    Efficient high-harmonic fast-wave (HHFW) heating in the National Spherical Torus Experiment Upgrade (NSTX-U) would facilitate experiments in turbulence, transport, fast-ion studies, and more. However, previous HHFW operation in NSTX exhibited a large loss of fast-wave power to the divertor along the scrape-off layer field lines for edge densities above the fast-wave cutoff. It was postulated that the wave amplitude is enhanced in the scrape-off layer due to cavity-like modes, and that these enhanced fields drive sheath losses through RF rectification. As part of ongoing work to confirm this hypothesis, we have developed a cylindrical cold-plasma model to identify and understand scenarios where a substantial fraction of wave power is confined to the plasma periphery. We previously identified a peculiar class of modes, named annulus resonances, that conduct approximately half of their wave power in the periphery and can also account for a significant fraction of the total wave power. Here, we study the influence of annulus resonances on wave field reconstructions and find instances where annulus-resonant modes dominate the spectrum and trap over half of the total wave power at the edge. The work is part of an ongoing effort to determine the mechanism underlying these scrape-off layer losses in NSTX, identify optimal conditions for operation in NSTX-U, and predict whether similar losses occur for the ion-cyclotron minority heating scheme for both current experiments and future devices such as ITER.

  6. An astrobiological study of high latitude martian analogue environments

    OpenAIRE

    Cousins, C.R.

    2010-01-01

    The search for life on Mars is in part reliant on the understanding of Martian environments, both past and present, in terms of what life may inhabit these environments, how this life may be preserved in the rock record, and how this rock record may be detected during future missions to Mars. In particular, the upcoming European Space Agency mission ‘ExoMars’ has the primary aim to identify evidence of past or present life on Mars, and the work presented here is carried out within this ...

  7. Ultra-Low Loss, Chip-Based Hollow-Core Waveguide Using High-Contrast Grating

    Science.gov (United States)

    2011-09-28

    delay circuit can be realized with a device loss that is order of magnitude lower than the current state- of-the-art in on-chip semiconductor...demonstrated as a high reflection mirrors at normal incident angle for VCSELs [5-7]. An HCG structure consists of a single layer of grating composed of a...nonlinearity measurement is currently limited by maximum power level of our EDF A ( ~ 18 dBm), the noise floor of OSA and the insufficient length of the

  8. The Role of High Dose Intratympanic Dexamethasone as Salvage Therapy for Idiopathic Sudden Sensorineural Hearing Loss.

    Science.gov (United States)

    Kordiš, Špela; Battelino, Saba

    2017-11-21

    The aim of this study was to assess the efficacy of a single high dose intratympanic (IT) dexamethasone (DEX) as salvage therapy for idiopathic sudden sensorineural hearing loss (ISSNHL) after unsuccessful treatment with oral corticosteroid (CS). This was a prospective open-label study of 59 patients treated with IT DEX after systemic CS therapy has failed. All patients received high dose (24 mg/mL) IT DEX in a single injection through myringotomy. Of the 59 patients, 40.7% showed improvement in their mean pure tone average (PTA) with IT DEX (p=0.005). The difference in the mean PTA after oral CS treatment only from baseline was not statistically significant (p=0.074). The time from onset of hearing loss to the start of therapy was significantly associated with the outcome (p=0.03). We determined that high dose IT DEX as salvage therapy was beneficial when the primary treatment with oral CS had failed. An early start of the treatment significantly influenced the improvement of hearing.

  9. Printed silver nanowire antennas with low signal loss at high-frequency radio.

    Science.gov (United States)

    Komoda, Natsuki; Nogi, Masaya; Suganuma, Katsuaki; Kohno, Kazuo; Akiyama, Yutaka; Otsuka, Kanji

    2012-05-21

    Silver nanowires are printable and conductive, and are believed to be promising materials in the field of printed electronics. However, the resistivity of silver nanowire printed lines is higher than that of metallic particles or flakes even when sintered at high temperatures of 100-400 °C. Therefore, their applications have been limited to the replacement of transparent electrodes made from high-resistivity materials, such as doped metallic oxides, conductive polymers, carbon nanotubes, or graphenes. Here we report that using printed silver nanowire lines, signal losses obtained in the high-frequency radio were lower than those obtained using etched copper foil antennas, because their surfaces were much smoother than those of etched copper foil antennas. This was the case even though the resistivity of silver nanowire lines was 43-71 μΩ cm, which is much higher than that of etched copper foil (2 μΩ cm). When printed silver nanowire antennas were heated at 100 °C, they achieved signal losses that were much lower than those of silver paste antennas comprising microparticles, nanoparticles, and flakes. Furthermore, using a low temperature process, we succeeded in remotely controlling a commercialized radio-controlled car by transmitting a 2.45 GHz signal via a silver nanowire antenna printed on a polyethylene terephthalate film.

  10. Irrecoverable pressure loss coefficients for two out-of-plane piping elbows at high Reynolds number

    Energy Technology Data Exchange (ETDEWEB)

    Coffield, R.D.; Hammond, R.B.; McKeown, P.T.

    1999-02-08

    Pressure drops of multiple piping elbows were experimentally determined for high Reynolds number flows. The testing described has been performed in order to reduce uncertainties in the currently used methods for predicting irrecoverable pressure losses and also to provide a qualification database for computational fluid dynamics (CFD) computer codes. The earlier high Reynolds number correlations had been based on extrapolations over several orders of magnitude in Reynolds number from where the original database existed. Recent single elbow test data shows about a factor of two lower elbow pressure loss coefficient (at 40x 106 Reynolds number) than those from current correlations. This single piping elbow data has been extended in this study to a multiple elbow configuration of two elbows that are 90o out-of-plane relative to each other. The effects of separation distance and Reynolds number have been correlated and presented in a form that can be used for design application. Contrary to earlier extrapolations from low Reynolds numbers (Re c 1.0x 106), a strong Reynolds number dependence was found to exist. The combination of the high Reynolds number single elbow data with the multiple elbow interaction effects measured in this study shows that earlier design correlations are conservative by significant margins at high Reynolds numbers. Qualification of CFD predictions with this new high Reynolds number database will help guide the need for additional high Reynolds number testing of other piping configurations. The study also included velocity measurements at several positions downstream of the first and second test elbows using an ultrasonic flowmeter. Reasonable agreement after the first test elbow was found relative to flow fields that are known to exist from low Reynolds number visual tests and also from CFD predictions. This data should help to qualify CFD predictions of the three-dimensional flow stream downstream of the second test elbow.

  11. Influence of body mass loss and myoglobinuria on the development of muscle fatigue after a marathon in a warm environment.

    Science.gov (United States)

    Del Coso, Juan; Salinero, Juan José; Abián-Vicen, Javier; González-Millán, Cristina; Garde, Sergio; Vega, Pablo; Pérez-González, Benito

    2013-03-01

    The aim of this study was to determine the changes in body mass and myoglobinuria concentration in recreational runners during a marathon in a warm environment, and the relation of these changes to muscle fatigue. We recruited 138 amateur runners (114 men and 24 women) for the study. Before the race, leg muscle power output was measured during a countermovement jump on a force platform, body weight was measured, and a urine sample was obtained. Within 3 min of race completion (28 °C; 46% relative humidity), the runners repeated the countermovement jump, body weight was measured again, and a second urine sample was obtained. Myoglobin concentration was determined in the urine samples. After the race, mean body mass reduction was 2.2% ± 1.2%. Fifty-five runners (40% of the total) reduced their body mass by less than 2%, and 10 runners (7.2%) reduced their body mass by more than 4%. Only 3 runners increased their body mass after the marathon. Mean leg muscle power reduction was 16% ± 10%. Twenty-four runners reduced their muscle power by over 30%. No myoglobin was detected in the prerace urine specimens, whereas postrace urinary myoglobin concentration increased to 3.5 ± 9.5 μg·mL(-1) (p < 0.05). Muscle power change after the marathon significantly correlated with postrace urine myoglobin concentration (r = -0.55; p < 0.001), but not with body mass change (r = -0.08; p = 0.35). After a marathon in a warm environment, interindividual variability in body mass change was high, but only 7% of the runners reduced their body mass by more than 4%. The correlation between myoglobinuria and muscle power change suggests that muscle fatigue is associated with muscle breakdown.

  12. Descriptive Epidemiology of Non-Time-Loss Injuries in Collegiate and High School Student-Athletes.

    Science.gov (United States)

    Kerr, Zachary Y; Lynall, Robert C; Roos, Karen G; Dalton, Sara L; Djoko, Aristarque; Dompier, Thomas P

    2017-05-01

      Research on non-time-loss (NTL) injuries, which result in less than 24 hours of restriction from participation, is limited.   To describe the epidemiology of NTL injuries among collegiate and high school student-athletes.   Descriptive epidemiology study.   Aggregate injury and exposure data collected from a convenience sample of National College Athletic Association varsity teams and 147 high schools in 26 states.   Collegiate and high school student-athletes participating in men's and boys' baseball, basketball, football, lacrosse, soccer, and wrestling and women's and girls' basketball, field hockey, lacrosse, soccer, softball, and volleyball during the 2009-2010 through 2013-2014 and the 2011-2012 through 2013-2014 academic years, respectively, participated. Collegiate student-athletes participating in men's and women's ice hockey were also included.   Injury data from the National Collegiate Athletic Association Injury Surveillance Program and the National Athletic Treatment, Injury and Outcomes Network were analyzed. Injury counts, rates per 1000 athlete-exposures (AEs), and rate ratios were reported with 95% confidence intervals (CIs).   A total of 11 899 and 30 122 NTL injuries were reported in collegiate and high school student-athletes, respectively. The proportion of NTL injuries in high school student-athletes (80.3%) was 1.61 times greater than that of collegiate student-athletes (49.9%; 95% CI = 1.59, 1.63). The NTL injury rate in high school student-athletes (8.75/1000 athlete-exposures [AEs]) was 2.18 times greater than that of collegiate student-athletes (4.02/1000 AEs; 95% CI = 2.13, 2.22). Men's ice hockey (5.27/1000 AEs) and boys' football (11.94/1000 AEs) had the highest NTL injury rates among collegiate and high school athletes, respectively. Commonly injured body parts in collegiate and high school student-athletes were the hip/thigh/upper leg (17.5%) and hand/wrist (18.2%), respectively. At both levels, contusions

  13. Graphene encapsulated rubber latex composites with high dielectric constant, low dielectric loss and low percolation threshold.

    Science.gov (United States)

    Tian, Ming; Zhang, Jing; Zhang, Liqun; Liu, Suting; Zan, Xiaoqing; Nishi, Toshio; Ning, Nanying

    2014-09-15

    A dielectric composite with high dielectric constant, low dielectric loss and low percolation threshold was prepared by using the combined strategy of encapsulating of graphene oxide nanosheets (GONS) on carboxylated nitrile rubber (XNBR) latex particles and the in situ thermal reduction in GONS at a moderate temperature. The encapsulation of GONS on XNBR latex particles was mainly realized via the hydrogen bonding interactions between GONS and XNBR during latex mixing. A segregated graphene network was obtained at a low content of thermally reduced graphene (TRG), resulting in a low percolation threshold (0.25 vol.%). The dielectric constant at 100 Hz obviously increased from 23 for pure XNBR to 2211 and 5542 for the composite with 0.5 vol.% and 0.75 vol.% of TRG, respectively. The dielectric loss of the composites retained at a low value (less than 1.5). Meanwhile, the elastic modulus only slightly increased with the presence of 0.1-0.5 vol.% of TRG, keeping the good flexibility of the dielectric composites. This study provides a simple, low-cost and effective method to prepare high performance dielectric composites, facilitating the wide application of dielectric materials. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Effects of canagliflozin on weight loss in high-fat diet-induced obese mice.

    Science.gov (United States)

    Ji, Wenjun; Zhao, Mei; Wang, Meng; Yan, Wenhui; Liu, Yuan; Ren, Shuting; Lu, Jun; Wang, Bing; Chen, Lina

    2017-01-01

    Canagliflozin, an inhibitor of sodium glucose co-transporter (SGLT) 2, has been shown to reduce body weight during the treatment of type 2 diabetes mellitus (T2DM). In this study, we sought to determine the role of canagliflozin in body weight loss and liver injury in obesity. C57BL/6J mice were fed a high-fat diet to simulate diet-induced obesity (DIO). Canagliflozin (15 and 60 mg/kg) was administered to DIO mice for 4 weeks. Orlistat (10 mg/kg) was used as a positive control. The body weight, liver weight, liver morphology, total cholesterol (TC) and triglyceride (TG) levels were examined. Signaling molecules, including diacylgycero1 acyltransferase-2 (DGAT2), peroxisome proliferation receptor alpha-1 (PPARα1), PPARγ1, PPARγ2 mRNA levels and the protein expression of SGLT2 were evaluated. Canagliflozin reduced body weight, especially the high-dose canagliflozin, and resulted in increased body weight loss compared with orlistat. Moreover, canagliflozin reduced the liver weight and the ratio of liver weight to body weight, lowered the serum levels of TC and TG, and ameliorated liver steatosis. During the canagliflozin treatment, SGLT2, DGAT2, PPARγ1 and PPARγ2 were inhibited, and PPARα1 was elevated in the liver tissues. This finding may explain why body weight was reduced and secondary liver injury was ameliorated in response to canagliflozin. Together, the results suggest that canagliflozin may be a potential anti-obesity strategy.

  15. Do Multiwell Plate High Throughput Assays Measure Loss of Cell Viability Following Exposure to Genotoxic Agents?

    Directory of Open Access Journals (Sweden)

    Razmik Mirzayans

    2017-08-01

    Full Text Available Cell-based assays in multiwell plates are widely used for radiosensitivity and chemosensitivity assessment with different mammalian cell types. Despite their relative ease of performance, such assays lack specificity as they do not distinguish between the cytostatic (reversible/sustained growth arrest and cytotoxic (loss of viability effects of genotoxic agents. We recently reported studies with solid tumor-derived cell lines demonstrating that radiosensitivity as measured by multiwell plate colorimetric (e.g., XTT and fluorimetric (e.g., CellTiter-Blue assays reflects growth arrest but not loss of viability. Herein we report similar observations with cancer cell lines expressing wild-type p53 (A549 lung carcinoma or mutant p53 (MDA–MB-231 breast carcinoma after treatment with the chemotherapeutic drug cisplatin. Importantly, we show that treatment of cancer cells with concentrations of cisplatin that result in 50% effect (i.e., IC50 in multiwell plate assays trigger the emergence of growth arrested cells that exhibit highly enlarged morphology, remain viable and adherent to the culture dish, and metabolize the tetrazolium salt 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyl-tetrazolium bromide (MTT to its formazan derivative. The emergence of markedly enlarged viable cells complicates the interpretation of chemosensitivity data obtained with multiwell plate high throughput assays. Relying solely on IC50 values could be misleading.

  16. Submillimeter residual losses in high-Tc superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Miller, David [Univ. of California, Berkeley, CA (United States)

    1993-09-01

    Bolometry was used obtain accurate submillimeter residual loss data for epitaxial films of YBa2Cu3O7 (YBCO), Tl2Ca2Ba2Cu3O10, Tl2CaBa2Cu2O8 (TCBCO), and Ba0.6K0.4BiO3 (BKBO). We were able to fit the absorptivity measured for Nb films to an Eliashberg strong coupling calculation; excellent agreement resulted between parameters from best fits and measured Residual Resistivity Ratio. Microwave surface resistance measurements made on the same YBCO and TCBCO films are in excellent agreement with submillimeter measurements. Absorptivities for all YBCO films studied are qualitatively similar, increasing smoothly with frequency, with no gap-like features below the well known absorption edge at 450 cm-1. Losses in YBCO films were fit to a weakly coupled grain model for the a-b plane conductivity. Strong phonon structure was observed in TCBCO films between 60 and 700 cm-1 (2 THz and 23 THz); these losses could not be fitted to the simple weakly coupled grain model, in contrast to the case for other high-Tc superconductors where phonon structure observed in ceramics are is absent in epitaxial oriented films and crystals because of electronic screening due to high conductivity of a-b planes. Absorptivity data for the BKBO films all show a strong absorption onset near the BCS tunneling gap of 3.5 kBTc. Comparison with strong coupling Eliashberg predictions and of a Kramers-Kronig analysis indicate that the absorption onset is consistent with a superconducting energy gap. Effects of magnetic field on residual losses in YBCO films show a resonant absorption feature in vicinity of predicted

  17. High-Resolution fMRI of Auditory Cortical Map Changes in Unilateral Hearing Loss and Tinnitus

    NARCIS (Netherlands)

    Ghazaleh, Naghmeh; Van der Zwaag, W.; Clarke, Stephanie; Ville, Dimitri Van De; Maire, Raphael; Saenz, Melissa

    2017-01-01

    Animal models of hearing loss and tinnitus observe pathological neural activity in the tonotopic frequency maps of the primary auditory cortex. Here, we applied ultra high-field fMRI at 7 T to test whether human patients with unilateral hearing loss and tinnitus also show altered functional activity

  18. Protective effect of doxycycline on germinal epithelial loss caused by a high-fat diet.

    Science.gov (United States)

    Delgado-Enciso, Ivan; García-Rivera, Alejandro; Madrigal-Pérez, M Violeta M; Rodriguez-Hernandez, Alejandrina; Lugo-Radillo, Agustin; Galvan-Salazar, Hector R; Soriano-Hernández, Alejandro D; Gómez-Tapia, Fernando; Martinez-Martinez, Rafael; Valdez-Velazquez, Laura L; Newton-Sanchez, Oscar A; Gonzalez-Alvarez, Rafael; Rodriguez-Sanchez, Iram P; Melnikov, Valery; Lara-Esqueda, Agustin; Guzman-Esquivel, Jose

    2014-05-01

    A high-fat diet and male obesity are aspects associated with germinal epithelial alterations and male infertility. Some reports have shown that certain tetracyclines can protect the germinal epithelium from toxic drugs. The aim of the present study design was to evaluate the possible effect of doxycycline on testicular germ cells in individuals fed a Western diet (atherogenic), using a murine model. Two groups of male mice (BALB/c) were fed a high-fat Western diet (HFD). One of these two groups was given doxycycline at a dose of 10 mg/kg/day (HFD+Dox). A third group was fed a standard rodent diet (SD group). After 6 months, the mice were euthanized and morphologic and histopathologic analyses were performed. Germinal epithelial height was similar between the SD group (54 μm) and the HFD+Dox group (53 μm) (p = 0.26), and it was significantly reduced in the HFD group (47 μm) (p = 0.0001). The degree of germinal epithelial loss (DGEL) was significantly lower in the SD (10) and HFD+Dox (12.5) groups than in the HFD group (30) (p = 0.0001 and =0.007, respectively). There were no differences in the DGEL between the SD and HFD+Dox groups (p = 0.42). Doxycycline administration was shown to prevent germinal epithelial loss in the testes of mice fed a high-fat diet. Future studies are necessary to evaluate the clinical usefulness of doxycycline or its analogs in persons with a habitual high-fat diet.

  19. Aspirin prevents bone loss with little mechanical improvement in high-fat-fed ovariectomized rats.

    Science.gov (United States)

    Lin, Sien; Lee, Wayne Y W; Huang, Meiling; Fu, Ziwei; Liang, Yanlong; Wu, Haiyou; Xu, Liangliang; Suen, Chun Wai; Huang, Jianping; Wu, Tie; Cui, Liao; Li, Gang

    2016-11-15

    Obesity and osteoporosis are often concurrently happened in the menopausal women. Obesity in menopausal women is not only related to a high risk of cardiovascular disease, but also results in a detrimental effect on bone health. This study aimed to investigate the effects of aspirin, a popular anti-thrombosis drug, on bone quantity and quality in the high-fat-fed animal model. Adult female rats were subjected to either sham operations or ovariectomized operations. The ovariectomized rats were orally administered with deionized water or standardized high fat emulsion with or without aspirin. All rats were injected with calcein before killed for the purpose of double in vivo labeling. Biochemistry, histomorphometry, micro-computed tomography analysis, mechanical test, and component analysis were performed after 12 weeks. In vitro cell culture was also performed to observe the effect of aspirin in osteogenesis. We found that high fat remarkably impaired bone formation and bone biomechanics. Aspirin treatment significantly prevented bone loss by increasing bone formation. In vitro studies also validated the enhancement of osteogenic differentiation. However, aspirin presented no significant improvement in bone mechanical properties. Component analysis shown aspirin could significantly increase the content of mineral, but had limited effect on the content of collagen. In conclusion, aspirin is beneficial for the prevention of bone loss; meanwhile, it may cause an imbalance in the components of bone which may weaken the mechanical properties. The current study provided further evidence that aspirin might not be powerful for the prevention of fracture in osteoporotic patients. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Corrosion and solubility in a TSP-buffered chemical environment following a loss of coolant accident: Part 3—Calcium

    Energy Technology Data Exchange (ETDEWEB)

    Olson, Sterling; Ali, Amir; LaBrier, Daniel [Department of Nuclear Engineering, University of New Mexico (United States); Blandford, Edward D, E-mail: edb@unm.edu [Department of Nuclear Engineering, University of New Mexico (United States); Howe, Kerry [Department of Civil Engineering, University of New Mexico (United States)

    2016-04-15

    Highlights: • Calcium leaching from NUKON fiberglass in borated TSP-buffered solution is independent of the level of fiberglass destruction. • The initial calcium release rate and the maximum calcium concentration increases with increased fiber concentration. • The calcium release in solution has a repeatable pattern of four distinct regions (prompt release, metastable, autocatalytic drop, and stable region) for all experiments. • Magnesium plays a significant role in initiating calcium precipitation in TSP-buffered environment. • Head loss through multi-constituents debris beds was found to increase progressively in all calcium concentration regions. - Abstract: Calcium that leaches from damaged or destroyed NUKON fiberglass in containment post a loss of coolant accident (LOCA) could lead to the formation of chemical precipitates. These precipitates could be filtered through the accumulated fibrous debris on the sump screen and compromising the emergency core cooling system (ECCS) sump pump performance. Reduced-scale leaching experiments were conducted on three solution inventory scales—bench (0.5 L), vertical column (31.5 L), and tank (1136 L) using three different flow conditions, and fiberglass concentrations (1.18–8 g/L) to investigate calcium release from NUKON fiber. All experiments were conducted in simulated post-LOCA water chemistry. (∼220 mM boric acid with ∼5.8 mM trisodium phosphate (TSP) buffer). Prior to the leaching tests, a preliminary experiment was carried out on the bench scale to determine the effect of the fiber preparation (unaltered and blended) method on calcium leaching. Results indicate that the extent of fiberglass destruction does not affect the amount of calcium released from fiberglass. Long-term calcium leach testing at constant temperature (80 °C) in borated TSP-buffered solution had repeatable behavior on all solution scales for different fiberglass concentrations. The calcium-leaching pattern can be divided into

  1. Weight loss enhances hepatic antioxidant status in a NAFLD model induced by high-fat diet.

    Science.gov (United States)

    Mendes, Iara Karise Santos; Matsuura, Cristiane; Aguila, Marcia Barbosa; Daleprane, Julio Beltrame; Martins, Marcela Anjos; Mury, Wanda Vianna; Brunini, Tatiana Marlowe Cunha

    2018-01-01

    Nonalcoholic fatty liver disease (NAFLD) is a benign condition that can progress to more severe liver damage in a process mediated, in part, by disturbances in redox balance. Additionally, some argue that it is set to become the main cause of end-stage liver disease in the near future. Here, we investigated whether diet-induced weight loss is able to reverse hepatic lipid accumulation and reduce oxidative stress in liver from C57BL/6 mice fed a high-fat (HF) diet. Male C57BL/6 mice were divided into 4 groups: standard chow (SC; 10% energy from fat, 16 weeks); HF (50% energy from fat, 16 weeks); SC-HF (SC for 8 weeks followed by HF for 8 weeks); and HF-SC (HF for 8 weeks followed by SC for 8 weeks). The HF diet during 8 (SC-HF) and 16 weeks (HF) downregulated messenger RNA levels and protein expression of Nrf2 and endogenous antioxidant enzymes (superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase) in the liver; caused liver steatosis; affected liver function markers; increased intra-abdominal and subcutaneous adipose tissue; and induced glucose intolerance and hypercholesterolemia compared with controls (SC). Diet-induced weight loss significantly reduced the intrahepatic lipid accumulation, improved glucose tolerance, and restored both gene and protein expression of the antioxidant enzymes. Our findings suggest that a dietary intervention aimed to induce weight loss may exert protective effects in NAFLD as it can reduce hepatic oxidative stress and intrahepatic lipid accumulation, which can hinder the progression of this condition to more severe states.

  2. Archaeal viruses from Yellowstone’s high temperature environments

    Energy Technology Data Exchange (ETDEWEB)

    M. Young; B. Wiedenheft; J. Snyder; J. Spuhler; F. Roberto; T. Douglas

    2005-01-01

    In general, our understanding of Archaea lags far behind our knowledge of the other two domains of life—Bacteria and Eukarya. Unlike the other domains of life, very few viruses of Archaea have been characterized. Of the approximately 4000 viruses described to date, only 36 are associated with archaeal hosts--many of these from thermophilic Crenarchaeota. In this work we describe the discovery, isolation and preliminary characterization of viruses and novel virus-like particles isolated directly from diverse thermal environments in Yellowstone National Park.

  3. Characteristics of a piezoresistive accelerometer in high frequency, high shock environments

    Energy Technology Data Exchange (ETDEWEB)

    Bateman, V.I.; Davie, N.T.; Brown, F.A.

    1993-12-31

    The characteristics of a piezoresistive accelerometer in shock environments are being studied at Sandia National Laboratories in the Mechanical Shock Testing Laboratory. A Hopkinson bar capability has been developed to extend our understanding of the piezoresistive accelerometer with and without mechanical isolation in the high frequency, high shock environments where measurements are being made. Two different Hopkinson bar materials are being used: titanium and beryllium. The characteristics of the piezoresistive accelerometer for frequencies of DC-10 kHz and shock magnitudes of up to 4,000 g as determined from measurements with a titanium Hopkinson bar are presented. The SNL uniaxial shock isolation technique has demonstrated acceptable characteristics for a temperature range of {minus}50{degree}F to +186{degree}F and a frequency bandwidth of DC to 10 kHz. These characteristics have been verified by the calibration of the Hopkinson bar used for accelerometer testing. The beryllium Hopkinson bar configuration is described. Preliminary characteristics of the piezoresistive accelerometer at a nominal shock level of 17,000 g for a frequency range of DC-50 kHz are presented.

  4. A High-Carbohydrate, High-Fiber, Low-Fat Diet Results in Weight Loss among Adults at High Risk of Type 2 Diabetes.

    Science.gov (United States)

    Sylvetsky, Allison C; Edelstein, Sharon L; Walford, Geoffrey; Boyko, Edward J; Horton, Edward S; Ibebuogu, Uzoma N; Knowler, William C; Montez, Maria G; Temprosa, Marinella; Hoskin, Mary; Rother, Kristina I; Delahanty, Linda M

    2017-11-01

    Background: Weight loss is a key factor in reducing diabetes risk. The Diabetes Prevention Program (DPP) is a completed clinical trial that randomly assigned individuals at high risk of diabetes to a placebo (PLBO), metformin (MET), or intensive lifestyle intervention (ILS) group, which included physical activity (PA) and reduced dietary fat intake.Objective: We aimed to evaluate the associations between diet and weight at baseline and to identify specific dietary factors that predicted weight loss among DPP participants.Methods: Diet was assessed by a food frequency questionnaire. The associations between intakes of macronutrients and various food groups and body weight among DPP participants at baseline were assessed by linear regression, adjusted for race/ethnicity, age, sex, calorie intake, and PA. Models that predicted weight loss at year 1 were adjusted for baseline weight, change in calorie intake, and change in PA and stratified by treatment allocation (MET, ILS, and PLBO). All results are presented as estimates ± SEs.Results: A total of 3234 participants were enrolled in the DPP; 2924 had completed dietary data (67.5% women; mean age: 50.6 ± 10.7 y). Adjusted for calorie intake, baseline weight was negatively associated with carbohydrate intake (-1.14 ± 0.18 kg body weight/100 kcal carbohydrate, P dietary fiber (-1.26 ± 0.28 kg/5 g fiber, P dietary fiber, and decreases in total fat and saturated fat intake.Conclusions: Higher carbohydrate consumption among DPP participants, specifically high-fiber carbohydrates, and lower total and saturated fat intake best predicted weight loss when adjusted for changes in calorie intake. Our results support the benefits of a high-carbohydrate, high-fiber, low-fat diet in the context of overall calorie reduction leading to weight loss, which may prevent diabetes in high-risk individuals. This trial was registered at clinicaltrials.gov as NCT00004992. © 2017 American Society for Nutrition.

  5. Selective Loss of Early Differentiated, Highly Functional PD1high CD4 T Cells with HIV Progression.

    Directory of Open Access Journals (Sweden)

    Robert M Paris

    Full Text Available The role of PD-1 expression on CD4 T cells during HIV infection is not well understood. Here, we describe the differential expression of PD-1 in CD127high CD4 T cells within the early/intermediate differentiated (EI (CD27highCD45RAlow T cell population among uninfected and HIV-infected subjects, with higher expression associated with decreased viral replication (HIV-1 viral load. A significant loss of circulating PD-1highCTLA-4low CD4 T cells was found specifically in the CD127highCD27highCD45RAlow compartment, while initiation of antiretroviral treatment, particularly in subjects with advanced disease, reversed these dynamics. Increased HIV-1 Gag DNA was also found in PD-1high compared to PD-1low ED CD4 T cells. In line with an increased susceptibility to HIV infection, PD-1 expression in this CD4 T cell subset was associated with increased activation and expression of the HIV co-receptor, CCR5. Rather than exhaustion, this population produced more IFN-g, MIP1-a, IL-4, IL-10, and IL-17a compared to PD-1low EI CD4 T cells. In line with our previous findings, PD-1high EI CD4 T cells were also characterized by a high expression of CCR7, CXCR5 and CCR6, a phenotype associated with increased in vitro B cell help. Our data show that expression of PD-1 on early-differentiated CD4 T cells may represent a population that is highly functional, more susceptible to HIV infection and selectively lost in chronic HIV infection.

  6. High dynamic, spectral, and polarized natural light environment acquisition

    Science.gov (United States)

    Porral, Philippe; Callet, Patrick; Fuchs, Philippe; Muller, Thomas; Sandré-Chardonnal, Etienne

    2015-03-01

    In the field of image synthesis, the simulation of material's appearance requires a rigorous resolution of the light transport equation. This implies taking into account all the elements that may have an influence on the spectral radiance, and that are perceived by the human eye. Obviously, the reflectance properties of the materials have a major impact in the calculations, but other significant properties of light such as spectral distribution and polarization must also be taken into account, in order to expect correct results. Unfortunately real maps of the polarized or spectral environment corresponding to a real sky do not exist. Therefore, it seemed necessary to focus our work on capturing such data, in order to have a system that qualifies all the properties of light and capable of powering simulations in a renderer software. As a consequence, in this work, we develop and characterize a device designed to capture the entire light environment, by taking into account both the dynamic range of the spectral distribution and the polarization states, in a measurement time of less than two minutes. We propose a data format inspired by polarimetric imaging and fitted for a spectral rendering engine, which exploits the "Stokes-Mueller formalism."

  7. On the Highly Stable Performance of Loss-Free Optical Burst Switching Networks

    Directory of Open Access Journals (Sweden)

    Milos Kozak

    2016-01-01

    Full Text Available Increase of bandwidth demand in data networks, driven by the continuous growth of the Internet and the increase of bandwidth greedy applications, raise the issue of how to support all the bandwidth requirements in the near future. Three optical switching paradigms have been defined and are being investigated: Optical Circuit Switching (OCS; Optical Packet Switching (OPS; and Optical Burst Switching (OBS. Among these paradigms, OBS is seen as the most appropriate solution today. However, OBS suffers from high burst loss as a result of contention in the bufferless mode of operation. This issue was investigated by Coutelen et al., 2009 who proposed the loss-free CAROBS framework whereby signal convertors of the optical signal to the electrical domain ensure electrical buffering. Convertors increase the network price which must be minimized to reduce the installation and operating costs of the CAROBS framework. An analysis capturing convertor requirements, with respect to the number of merging flows and CAROBS node offered load, was carried out. We demonstrated the convertor location significance, which led to an additional investigation of the shared wavelength convertors scenario. Shared wavelength convertors significantly decrease the number of required convertors and show great promise for CAROBS. Based on this study we can design a CAROBS network to contain a combination of simple and complex nodes that include none or some convertors respectively, a vital feature of network throughput efficiency and cost.

  8. Energy loss of a high-charge bunched electron beam in plasma: Analysis

    Directory of Open Access Journals (Sweden)

    N. Barov

    2004-06-01

    Full Text Available There has been much recent experimental and theoretical interest in the blowout regime of plasma wakefield acceleration, which features ultrahigh accelerating fields, linear transverse focusing forces, and nonlinear plasma motion. A quantitative understanding of the blowout regime including all these effects has, to this point, been available only through detailed simulations. This paper represents an initial step towards an analytical theory of this regime, in which the mechanism of energy loss in the drive beam is investigated. We find, first from examination of electromagnetic particle-in-cell simulations, and then through analytical investigations, that under short pulse, high-charge conditions, the plasma electrons receive a strong initial push along the direction of beam motion. This nonlinear effect is unanticipated by linear theory, where the return current motion is in the opposite direction. In the limit of short pulses (the δ-function limit, the beam energy loss is shown to be linear in charge even with a nonlinear plasma response dominated by relativistic, electromagnetic effects, despite the fact that the initial plasma electron response changes qualitatively from the familiar electrostatic, nonrelativistic limit.

  9. High dose compressive loads attenuate bone mineral loss in humans with spinal cord injury

    Science.gov (United States)

    Dudley-Javoroski, S.; Saha, P. K.; Liang, G.; Li, C.; Gao, Z.

    2012-01-01

    Summary People with spinal cord injury (SCI) lose bone and muscle integrity after their injury. Early doses of stress, applied through electrically induced muscle contractions, preserved bone density at high-risk sites. Appropriately prescribed stress early after the injury may be an important consideration to prevent bone loss after SCI. Introduction Skeletal muscle force can deliver high compressive loads to bones of people with spinal cord injury (SCI). The effective osteogenic dose of load for the distal femur, a chief site of fracture, is unknown. The purpose of this study is to compare three doses of bone compressive loads at the distal femur in individuals with complete SCI who receive a novel stand training intervention. Methods Seven participants performed unilateral quadriceps stimulation in supported stance [150% body weight (BW) compressive load—“High Dose” while opposite leg received 40% BW—“Low Dose”]. Five participants stood passively without applying quadriceps electrical stimulation to either leg (40% BW load—“Low Dose”). Fifteen participants performed no standing (0% BW load—“Untrained”) and 14 individuals without SCI provided normative data. Participants underwent bone mineral density (BMD) assessment between one and six times over a 3-year training protocol. Results BMD for the High Dose group significantly exceeded BMD for both the Low Dose and the Untrained groups (p0.05), indicating that BMD for participants performing passive stance did not differ from individuals who performed no standing. High-resolution CT imaging of one High Dose participant revealed 86% higher BMD and 67% higher trabecular width in the High Dose limb. Conclusion Over 3 years of training, 150% BW compressive load in upright stance significantly attenuated BMD decline when compared to passive standing or to no standing. High-resolution CT indicated that trabecular architecture was preserved by the 150% BW dose of load. PMID:22187008

  10. Modelling and Control of Stepper Motors for High Accuracy Positioning Systems Used in Radioactive Environments

    CERN Document Server

    Picatoste Ruilope, Ricardo; Masi, Alessandro

    Hybrid Stepper Motors are widely used in open-loop position applications. They are the choice of actuation for the collimators in the Large Hadron Collider, the largest particle accelerator at CERN. In this case the positioning requirements and the highly radioactive operating environment are unique. The latter forces both the use of long cables to connect the motors to the drives which act as transmission lines and also prevents the use of standard position sensors. However, reliable and precise operation of the collimators is critical for the machine, requiring the prevention of step loss in the motors and maintenance to be foreseen in case of mechanical degradation. In order to make the above possible, an approach is proposed for the application of an Extended Kalman Filter to a sensorless stepper motor drive, when the motor is separated from its drive by long cables. When the long cables and high frequency pulse width modulated control voltage signals are used together, the electrical signals difer greatl...

  11. On the Conductive Loss of High-Q Frequency Reconfigurable Antennas for LTE Frequencies

    DEFF Research Database (Denmark)

    Barrio, Samantha Caporal Del

    2018-01-01

    , the soldering tin and the conductivity of the antenna material. It shows that conductive loss from the non-perfect electric conductor becomes the main source of loss for certain Q values. This loss is intrinsic to the antenna manufacturing and cannot be mitigated even with the best conductor, i.e. silver...

  12. Neutrophilic iron oxidizers adapted to highly oxic environments

    DEFF Research Database (Denmark)

    Gülay, Arda; Musovic, Sanin; Albrechtsen, Hans-Jørgen

    carbon) while oxygen (O2) is the electron acceptor provided during the aeration process. Numerous previous studies have described neutrophilic iron oxidizers as a bacterial guild with a special niche preference, especially the transition zone between aerobic and anoxic regions, where abiotic chemical...... oxidation of iron would be retarded. For that reason, no attempts have been documented to describe the density and diversity of iron oxidizing bacteria (FeOB) in oxic neutrophilic environments. Under low temperatures (5 to 10°C) conditions, as typically found in groundwater, extremely low rates of chemical...... iron oxidation (t1/2: 315min.) have been documented. This assumed slow chemical oxidation of Fe2 + in rapid sand filters may allow certain bacteria to oxidize iron concurrently with the ongoing slow chemical oxidation. Hence, we aimed to investigate the abundance, diversity, and spatial distribution...

  13. High-Speed Mobile Communications in Hostile Environments

    CERN Document Server

    AUTHOR|(SzGeCERN)739920; Sierra, Rodrigo; Chapron, Frederic; CERN. Geneva. IT Department

    2015-01-01

    With the inexorable increase in the use of mobile devices, wireless connectivity is expected by users anywhere, anytime. In general, this requirement is addressed in office buildings or public locations through the use of Wi-Fi technology but Wi-Fi is not well adapted for use in large experiment halls and complex underground environments, especially those where radiation exposure is an issue, such as the LHC tunnel and experimental caverns. 4G/LTE technology, however, looks to be well adapted to addressing mobility needs in such areas. We report here the studies CERN has undertaken on the use of 4G/LTE in the LHC tunnel, presenting results on the data throughput that can be achieved and discussing issues such as the provision of a consistent user experience.

  14. Seizing Workplace Learning Affordances in High-Pressure Work Environments

    DEFF Research Database (Denmark)

    Gnaur, Dorina

    2010-01-01

    to produce counterproductive effects with regard to employee well-being and the quality of customer interactions. Yet, almost contrarily, based on evidence from ethnographic field data from a call centre for sales and customer support, a particular instance of individual agency is identified as a means...... of emotional labour, this paper supports a more differentiated and nuanced view of tele-service workers, marked by the exercise of their subjectivity and agency. It argues that an apparently harsh work environment creates distinct conditions for rich learning and practice regeneration when populated......Work in call centres is often presented as a form of unskilled labour characterized by routinization, technological surveillance and tight management control aimed at reaching intensive performance targets. Beyond delivering business objectives, this control and efficiency strategy is often held...

  15. Predicting seed dormancy loss and germination timing for Bromus tectorum in a semi-arid environment using hydrothermal time models

    Science.gov (United States)

    Susan E. Meyer; Phil S. Allen

    2009-01-01

    A principal goal of seed germination modelling for wild species is to predict germination timing under fluctuating field conditions. We coupled our previously developed hydrothermal time, thermal and hydrothermal afterripening time, and hydration-dehydration models for dormancy loss and germination with field seed zone temperature and water potential measurements from...

  16. A Prediction Study of Path Loss Models from 2-73.5 GHz in an Urban-Macro Environment

    DEFF Research Database (Denmark)

    Thomas, Timothy; Rybakowski, Marcin; Sun, Shu

    2016-01-01

    It is becoming clear that 5G wireless systems will encompass frequencies from around 500 MHz all the way to around 100 GHz. To adequately assess the performance of 5G systems in these different bands, path loss (PL) models will need to be developed across this wide frequency range. The PL models ...

  17. Working in a hot environment; perspiration loss; a drink for persons working under hot conditions, part 2

    Science.gov (United States)

    Glatzel, H.

    1978-01-01

    Losses of various nutrients through sweat of persons working under hot conditions were considered. On the basis of these considerations a supplemental drink was formulated consisting of 1 liter of water per hour containing salt, potassium chloride, iron, thiamine and ascorbic acid.

  18. Reducing fischer-tropsch catalyst attrition losses in high agitation reaction systems

    Science.gov (United States)

    Singleton, Alan H.; Oukaci, Rachid; Goodwin, James G.

    2001-01-01

    A method for reducing catalyst attrition losses in hydrocarbon synthesis processes conducted in high agitation reaction systems; a method of producing an attrition-resistant catalyst; a catalyst produced by such method; a method of producing an attrition-resistant catalyst support; and a catalyst support produced by such method. The inventive method of reducing catalyst attrition losses comprises the step of reacting a synthesis gas in a high agitation reaction system in the presence of a catalyst. In one aspect, the catalyst preferably comprises a .gamma.-alumina support including an amount of titanium effective for increasing the attrition resistance of the catalyst. In another aspect, the catalyst preferably comprises a .gamma.-alumina support which has been treated, after calcination, with an acidic, aqueous solution. The acidic aqueous solution preferably has a pH of not more than about 5. In another aspect, the catalyst preferably comprises cobalt on a .gamma.-alumina support wherein the cobalt has been applied to the .gamma.-alumina support by totally aqueous, incipient wetness-type impregnation. In another aspect, the catalyst preferably comprises cobalt on a .gamma.-alumina support with an amount of a lanthana promoter effective for increasing the attrition resistance of the catalyst. In another aspect, the catalyst preferably comprises a .gamma.-alumina support produced from boehmite having a crystallite size, in the 021 plane, in the range of from about 30 to about 55 .ANG.ngstrons. In another aspect, the inventive method of producing an attrition-resistant catalyst comprises the step of treating a .gamma.-alumina support, after calcination of and before adding catalytic material to the support, with an acidic solution effective for increasing the attrition resistance of the catalyst. In another aspect, the inventive method of producing an attrition-resistant catalyst support comprises the step of treating calcined .gamma.-alumina with an acidic, aqueous

  19. High dietary sodium chloride causes further protein loss during head-down tilt bed rest (HDBR)

    Science.gov (United States)

    Buehlmeier, Judith; Frings-Meuthen, Petra; Baecker, Natalie; Stehle, Peter; Heer, Martina

    Human spaceflight is associated with a loss of body protein most likely caused by muscle degradation. Additionally astronauts tend towards a high dietary intake of sodium chloride (NaCl), which has recently been shown to induce low grade metabolic acidosis (Frings-Meuthen et al. JBMR, Epub 2007). In several patterns, e.g. chronical renal failure, metabolic acidosis is associated with protein catabolism. We therefore hypothesized that high dietary intake of NaCl enforces protein losses in HDBR, a model for physiological changes in microgravity (µG). Eight healthy male subjects (mean age 26.25 ± 3.5; mean body weight: 78.5 ± 4.1 kg) participated in a 14-day bed rest study in the metabolic ward of the DLR - Institute of Aerospace Medicine, Cologne, Germany. The study was carried out in a cross over design, consisting of two phases, each lasting 22 days (5 days adaptation, 14 days 6° HDBR and 3 days recovery). Both study phases were identical with respect to environmental conditions and study protocol. Subjects received an individually tailored, weight-maintaining diet containing 1.3 g protein/kg/day. The diet was identical in both study phases with the exception of NaClintake: Every subject received a low NaCl diet (0.7 mmol/kg/day) in one phase and a high NaCl diet (7.7 mmol/kg/day) in another one. Blood gas for analysis of acid-base balance was implemented at days 4 and 5 of adaptation, days 2, 5, 7, 10, 12, 14 of HDBR and days 2, 3 of recovery. Continuous urine collection started on the first day in the metabolic ward to analyze nitrogen excretion. Nitrogen balance was calculated from the difference between protein intake and urinary nitrogen excretion, determined by use of chemiluminescence (Grimble et al. JPEN, 1988). Plasma pH did not change significantly (p=0.285), but plasma bicarbonate and base excess decreased (p=0.0175; p=0.0093) with high NaCl intake in HDBR compared to the low NaCl diet. Nitrogen balance in HDBR was negative, as expected in

  20. High-tension corona controlled ozone generator for environment protection

    Science.gov (United States)

    Vijayan, T.; Patil, Jagadish G.

    2010-02-01

    Engineering details of a high voltage driven corona-plasma ozone generator are described. The plasma diode of generator has coaxial cylindrical geometry with cathode located inside anode. Cathode is made of a large number of radial gas nozzles arranged on central tubular mast which admits oxygen gas. The sharp endings of the nozzles along with a set of corona rings create the high electric field at the cathode required for formation of dense corona plume responsible for O3 evolution. A model of coronal plasma generation and ozone production is presented. The plasma formation is strongly dependent on the electric field and temperature in side diode where a high electron density in a low temperature negative corona is suited for high ozone yields. These are established by suitable regulation of A-K gap, voltage, oxygen pressure, and cathode-nozzle population.

  1. Beam test results of CMS RPCs at high eta region under high-radiation environment

    CERN Document Server

    Park, S; Bahk, S Y; Hong, B; Hong, S J; Kang, D H; Kang, T I; Kim, T J; Kim, Y J; Kim, Y U; Koo, D G; Lee, H W; Lee, K S; Lee, S J; Lim, J K; Moon, D H; Nam, S K; Oh, J K; Park, W J; Rhee, J T; Ryu, M S; Shim, H H; Sim, K S

    2004-01-01

    The Compact Muon Solenoid (CMS) forward resistivity plate chambers (RPCs) at the high eta region must be operated in presence of a radiation-induced rate as high as 1 kHz/cm**2. It is still unknown if the RPCs coated with linseed oil can be operated under such a high- radiation environment over the lifetime of CMS. Non-oiled RPCs may be one of the options since phenolic or melamine-coated bakelite is chemically stabler than linseed oil. We have constructed oiled and non-oiled RPCs at the high eta region of CMS using phenolic bakelite and tested them in the Gamma Irradiation Facility at CERN. While both RPCs show the same characteristics in the efficiency and the strip multiplicity, the non-oiled RPC generates an intrinsic noise rate of 50 Hz/cm**2, compared to only 5 Hz/cm**2 for the oiled RPC, both at 10.0kV which is about 100 V above the 95% knee of the efficiency curve.

  2. Hardening electronic devices against very high total dose radiation environments

    Science.gov (United States)

    Buchanan, B.; Shedd, W.; Roosild, S.; Dolan, R.

    1972-01-01

    The possibilities and limitations of hardening silicon semiconductor devices to the high neutron and gamma radiation levels and greater than 10 to the eighth power rads required for the NERVA nuclear engine development are discussed. A comparison is made of the high dose neutron and gamma hardening potential of bipolar, metal insulator semiconductors and junction field effect transistors. Experimental data is presented on device degradation for the high neutron and gamma doses. Previous data and comparisons indicate that the JFET is much more immune to the combined neutron displacement and gamma ionizing effects than other transistor types. Experimental evidence is also presented which indicates that p channel MOS devices may be able to meet the requirements.

  3. Objectively measured habitual physical activity in a highly obesogenic environment.

    Science.gov (United States)

    McLure, S A; Summerbell, C D; Reilly, J J

    2009-05-01

    While the prevalence of overweight and obesity among children continues to grow nationally, prevalence in the North-East of England is among the highest in the UK. The objective of this study was to investigate the habitual physical activity levels in a particularly obesogenic environment in the North-East of England. Eight primary schools were selected using a stratified random sampling frame ranking average deprivation levels. Participating children (n = 246, mean age 10 years) wore an accelerometer (Actigraph, GT-256) over five consecutive days (weekend plus three weekdays). Total daily moderate-to-vigorous intensity physical activity was calculated using thresholds by Puyau and colleagues. Only 7% (17/246) of children were sufficiently active. Boys were more physically active than girls (766 +/- 268 vs. 641 +/- 202 counts/min, 95% CI for the difference 63-186 cpm.). Total physical activity was not influenced significantly by deprivation levels or weight status, and there were no significant differences in physical activity between school or weekend days. The North-East of England is a recognized 'hot spot' for paediatric obesity and the present study shows that low levels of habitual physical activity are typical. Choice of accelerometry threshold affects both the apparent amount of physical activity and the ability to detect groups with particularly low levels of physical activity.

  4. Reliability of High I/O High Density CCGA Interconnect Electronic Packages under Extreme Thermal Environment

    Science.gov (United States)

    Ramesham, Rajeshuni

    2012-01-01

    This paper provides the experimental test results of advanced CCGA packages tested in extreme temperature thermal environments. Standard optical inspection and x-ray non-destructive inspection tools were used to assess the reliability of high density CCGA packages for deep space extreme temperature missions. Ceramic column grid array (CCGA) packages have been increasing in use based on their advantages such as high interconnect density, very good thermal and electrical performances, compatibility with standard surface-mount packaging assembly processes, and so on. CCGA packages are used in space applications such as in logic and microprocessor functions, telecommunications, payload electronics, and flight avionics. As these packages tend to have less solder joint strain relief than leaded packages or more strain relief over lead-less chip carrier packages, the reliability of CCGA packages is very important for short-term and long-term deep space missions. We have employed high density CCGA 1152 and 1272 daisy chained electronic packages in this preliminary reliability study. Each package is divided into several daisy-chained sections. The physical dimensions of CCGA1152 package is 35 mm x 35 mm with a 34 x 34 array of columns with a 1 mm pitch. The dimension of the CCGA1272 package is 37.5 mm x 37.5 mm with a 36 x 36 array with a 1 mm pitch. The columns are made up of 80% Pb/20%Sn material. CCGA interconnect electronic package printed wiring polyimide boards have been assembled and inspected using non-destructive x-ray imaging techniques. The assembled CCGA boards were subjected to extreme temperature thermal atmospheric cycling to assess their reliability for future deep space missions. The resistance of daisy-chained interconnect sections were monitored continuously during thermal cycling. This paper provides the experimental test results of advanced CCGA packages tested in extreme temperature thermal environments. Standard optical inspection and x-ray non

  5. High temperature corrosion of nickel-base alloys in environments containing alkali sulphate

    Energy Technology Data Exchange (ETDEWEB)

    Pettersson, Rachel; Flyg, Jesper; Caddeo, Sophie [Corrosion and Metals Research Institute, KIMAB, Stockholm (Sweden); Karlsson, Fredrik [Siemens Industrial Turbomachinery, Finspong (Sweden)

    2007-02-15

    This work is directed towards producing data to assist in lifetime assessment of components in gas turbines run in severely polluted industrial environments where the main corrosive species is SO{sub 2}, which can condense to form alkali sulphates. Corrosion rates have been measured for the base materials, in order to assess the worst-case scenario, in which cracks or other damage has occurred to the protective coating. The information is expected to be of value to manufacturers, owners and inspectors of gas turbines. Six nickel-base superalloys were subject to thermal cycles of 160 hours duration, and 0.8mg/cm{sup 2} of 20 mol % Na{sub 2}SO{sub 4} + 80mol% K{sub 2}SO{sub 4} was applied before each cycle. The test temperatures were 850 deg C and 900 deg C, with maximum test durations of 24 cycles and 12 cycles respectively. The metal loss was assessed by metallography of cross sections and the sulphidation attack was found to be very uneven. Mass change data indicated that the corrosion process was largely linear in character, and probability plots and estimations of the propagation rate of corrosion based on the linear growth assumption were produced. The performance of the alloys increased with increasing chromium content. The single crystal materials CMSX4 and MD2 showed such high corrosion rates that their use in severely contaminated industrial environments is considered inadvisable. The best performance was shown by Inconel 939 and Inconel 6203, so that even if cracks occur in the protective coating, a reasonable remaining lifetime can be expected for these materials. Sulphide formation occurred at the reaction front in all cases and mixed sulphides such as Ta-Ni or Ti-Nb sulphides were often present. The work has news value since very little long-term data is currently available for materials performance in severely sulphidising environments. The project goals in terms of exposures and metrology have been fully realised. Contributions have been made to the

  6. Diets with High or Low Protein Content and Glycemic Index for Weight-Loss Maintenance

    Science.gov (United States)

    Larsen, Thomas Meinert; Dalskov, Stine-Mathilde; van Baak, Marleen; Jebb, Susan A.; Papadaki, Angeliki; Pfeiffer, Andreas F.H.; Martinez, J. Alfredo; Handjieva-Darlenska, Teodora; Kunešová, Marie; Pihlsgård, Mats; Stender, Steen; Holst, Claus; Saris, Wim H.M.; Astrup, Arne

    2012-01-01

    Background Studies of weight-control diets that are high in protein or low in glycemic index have reached varied conclusions, probably owing to the fact that the studies had insufficient power. Methods We enrolled overweight adults from eight European countries who had lost at least 8% of their initial body weight with a 3.3-MJ (800-kcal) low-calorie diet. Participants were randomly assigned, in a two-by-two factorial design, to one of five ad libitum diets to prevent weight regain over a 26-week period: a low-protein and low-glycemic-index diet, a low-protein and high-glycemic-index diet, a high-protein and low-glycemic-index diet, a high-protein and high-glycemic-index diet, or a control diet. Results A total of 1209 adults were screened (mean age, 41 years; body-mass index [the weight in kilograms divided by the square of the height in meters], 34), of whom 938 entered the low-calorie-diet phase of the study. A total of 773 participants who completed that phase were randomly assigned to one of the five maintenance diets; 548 completed the intervention (71%). Fewer participants in the high-protein and the low-glycemic-index groups than in the low-protein–high-glycemic-index group dropped out of the study (26.4% and 25.6%, respectively, vs. 37.4%; P = 0.02 and P = 0.01 for the respective comparisons). The mean initial weight loss with the low-calorie diet was 11.0 kg. In the analysis of participants who completed the study, only the low-protein–high-glycemic-index diet was associated with subsequent significant weight regain (1.67 kg; 95% confidence interval [CI], 0.48 to 2.87). In an intention-to-treat analysis, the weight regain was 0.93 kg less (95% CI, 0.31 to 1.55) in the groups assigned to a high-protein diet than in those assigned to a low-protein diet (P = 0.003) and 0.95 kg less (95% CI, 0.33 to 1.57) in the groups assigned to a low-glycemic-index diet than in those assigned to a high-glycemic-index diet (P = 0.003). The analysis involving

  7. Diets with high or low protein content and glycemic index for weight-loss maintenance.

    Science.gov (United States)

    Larsen, Thomas Meinert; Dalskov, Stine-Mathilde; van Baak, Marleen; Jebb, Susan A; Papadaki, Angeliki; Pfeiffer, Andreas F H; Martinez, J Alfredo; Handjieva-Darlenska, Teodora; Kunešová, Marie; Pihlsgård, Mats; Stender, Steen; Holst, Claus; Saris, Wim H M; Astrup, Arne

    2010-11-25

    Studies of weight-control diets that are high in protein or low in glycemic index have reached varied conclusions, probably owing to the fact that the studies had insufficient power. We enrolled overweight adults from eight European countries who had lost at least 8% of their initial body weight with a 3.3-MJ (800-kcal) low-calorie diet. Participants were randomly assigned, in a two-by-two factorial design, to one of five ad libitum diets to prevent weight regain over a 26-week period: a low-protein and low-glycemic-index diet, a low-protein and high-glycemic-index diet, a high-protein and low-glycemic-index diet, a high-protein and high-glycemic-index diet, or a control diet. A total of 1209 adults were screened (mean age, 41 years; body-mass index [the weight in kilograms divided by the square of the height in meters], 34), of whom 938 entered the low-calorie-diet phase of the study. A total of 773 participants who completed that phase were randomly assigned to one of the five maintenance diets; 548 completed the intervention (71%). Fewer participants in the high-protein and the low-glycemic-index groups than in the low-protein-high-glycemic-index group dropped out of the study (26.4% and 25.6%, respectively, vs. 37.4%; P=0.02 and P=0.01 for the respective comparisons). The mean initial weight loss with the low-calorie diet was 11.0 kg. In the analysis of participants who completed the study, only the low-protein-high-glycemic-index diet was associated with subsequent significant weight regain (1.67 kg; 95% confidence interval [CI], 0.48 to 2.87). In an intention-to-treat analysis, the weight regain was 0.93 kg less (95% CI, 0.31 to 1.55) in the groups assigned to a high-protein diet than in those assigned to a low-protein diet (P=0.003) and 0.95 kg less (95% CI, 0.33 to 1.57) in the groups assigned to a low-glycemic-index diet than in those assigned to a high-glycemic-index diet (P=0.003). The analysis involving participants who completed the intervention

  8. Comparison of two dose-response relationship of noise exposure evaluation results with high frequency hearing loss.

    Science.gov (United States)

    Zhang, Hua; Li, Nan; Yang, Qiu-Ling; Qiu, Wei; Zhu, Liang-Liang; Tao, Li-Yuan; Davis, Robert I; Heyer, Nicholas; Zhao, Yi-Ming

    2015-03-20

    Complex noise and its relation to hearing loss are difficult to measure and evaluate. In complex noise measurement, individual exposure results may not accurately represent lifetime noise exposure. Thus, the mean L Aeq,8 h values of individuals in the same workgroup were also used to represent L Aeq,8 h in our study. Our study aimed to explore whether the mean exposure levels of workers in the same workgroup represented real noise exposure better than individual exposure levels did. A cross-sectional study was conducted to establish a model for cumulative noise exposure (CNE) and hearing loss in 205 occupational noise-exposed workers who were recruited from two large automobile manufacturers in China. We used a personal noise dosimeter and a questionnaire to determine the workers' occupational noise exposure levels and exposure times, respectively. A qualified audiologist used standardized audiometric procedures to assess hearing acuity after at least 16 h of noise avoidance. We observed that 88.3% of workers were exposed to more than 85 dB(A) of occupational noise (mean: 89.3 ± 4.2 dB(A)). The personal CNE (CNEp) and workgroup CNE (CNEg) were 100.5 ± 4.7 dB(A) and 100.5 ± 2.9 dB(A), respectively. In the binary logistic regression analysis, we established a regression model with high-frequency hearing loss as the dependent variable and CNE as the independent variable. The Wald value was 5.014 with CNEp as the independent variable and 8.653 with CNEg as the independent variable. Furthermore, we found that the figure for CNEg was more similar to the stationary noise reference than CNEp was. The CNEg model was better than the CNEp model. In this circumstance, we can measure some subjects instead of the whole workgroup and save manpower. In a complex noise environment, the measurements of average noise exposure level of the workgroup can improve the accuracy and save manpower.

  9. High-Trait and Low-Trait Angry College Students: A Comparison of Family Environments.

    Science.gov (United States)

    Lopez, Frederick G.; Thurman, Christopher W.

    1993-01-01

    Investigated differences in family environments of high- and low-trait angry college students (n=202). Found that high-trait angry students described their family environments as significantly less cohesive, less emotionally expressive, more conflictual, and more disorganized than did their low-trait angry counterparts. Findings have implications…

  10. Assessment of Mechanical Properties and Damage of High Performance Concrete Subjected to Magnesium Sulfate Environment

    Directory of Open Access Journals (Sweden)

    Sheng Cang

    2017-01-01

    Full Text Available Sulfate attack is one of the most important problems affecting concrete structures, especially magnesium sulfate attack. This paper presents an investigation on the mechanical properties and damage evolution of high performance concrete (HPC with different contents of fly ash exposure to magnesium sulfate environment. The microstructure, porosity, mass loss, dimensional variation, compressive strength, and splitting tensile strength of HPC were investigated at various erosion times up to 392 days. The ultrasonic pulse velocity (UPV propagation in HPC at different erosion time was determined by using ultrasonic testing technique. A relationship between damage and UPV of HPC was derived according to damage mechanics, and a correlation between the damage of HPC and erosion time was obtained eventually. The results indicated that (1 the average increasing amplitude of porosity for HPCs was 34.01% before and after exposure to magnesium sulfate solution; (2 the damage evolution of HPCs under sulfate attack could be described by an exponential fitting; (3 HPC containing 20% fly ash had the strongest resistance to magnesium sulfate attack.

  11. High-impact exercise in rats prior to and during suspension can prevent bone loss.

    Science.gov (United States)

    Yanagihara, G R; Paiva, A G; Gasparini, G A; Macedo, A P; Frighetto, P D; Volpon, J B; Shimano, A C

    2016-03-01

    High-impact exercise has been considered an important method for treating bone loss in osteopenic experimental models. In this study, we investigated the effects of osteopenia caused by inactivity in femora and tibiae of rats subjected to jump training using the rat tail suspension model. Eight-week-old female Wistar rats were divided into five groups (n=10 each group): jump training for 2 weeks before suspension and training during 3 weeks of suspension; jump training for 2 weeks before suspension; jump training only during suspension; suspension without any training; and a control group. The exercise protocol consisted of 20 jumps/day, 5 days/week, with a jump height of 40 cm. The bone mineral density of the femora and tibiae was measured by double energy X-ray absorptiometry and the same bones were evaluated by mechanical tests. Bone microarchitecture was evaluated by scanning electron microscopy. One-way ANOVA was used to compare groups. Significance was determined as Pbone mineral density, mechanical properties and bone microarchitecture, the beneficial effects were greater in the bones of animals subjected to pre-suspension training and subsequently to training during suspension, compared with the bones of animals subjected to pre-suspension training or to training during suspension. Our results indicate that a period of high impact exercise prior to tail suspension in rats can prevent the installation of osteopenia if there is also training during the tail suspension.

  12. High-impact exercise in rats prior to and during suspension can prevent bone loss

    Energy Technology Data Exchange (ETDEWEB)

    Yanagihara, G.R.; Paiva, A.G.; Gasparini, G.A.; Macedo, A.P. [Laboratório de Bioengenharia, Departamento de Biomecânica, Medicina e Reabilitação do Aparelho Locomotor, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil); Frighetto, P.D. [Instituto Federal de Educação, Ciência e Tecnologia de São Paulo, São Paulo, SP (Brazil); Volpon, J.B.; Shimano, A.C. [Laboratório de Bioengenharia, Departamento de Biomecânica, Medicina e Reabilitação do Aparelho Locomotor, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil)

    2016-02-02

    High-impact exercise has been considered an important method for treating bone loss in osteopenic experimental models. In this study, we investigated the effects of osteopenia caused by inactivity in femora and tibiae of rats subjected to jump training using the rat tail suspension model. Eight-week-old female Wistar rats were divided into five groups (n=10 each group): jump training for 2 weeks before suspension and training during 3 weeks of suspension; jump training for 2 weeks before suspension; jump training only during suspension; suspension without any training; and a control group. The exercise protocol consisted of 20 jumps/day, 5 days/week, with a jump height of 40 cm. The bone mineral density of the femora and tibiae was measured by double energy X-ray absorptiometry and the same bones were evaluated by mechanical tests. Bone microarchitecture was evaluated by scanning electron microscopy. One-way ANOVA was used to compare groups. Significance was determined as P<0.05. Regarding bone mineral density, mechanical properties and bone microarchitecture, the beneficial effects were greater in the bones of animals subjected to pre-suspension training and subsequently to training during suspension, compared with the bones of animals subjected to pre-suspension training or to training during suspension. Our results indicate that a period of high impact exercise prior to tail suspension in rats can prevent the installation of osteopenia if there is also training during the tail suspension.

  13. The Efficacy of Routine Screening for High-Frequency Hearing Loss in Adults and Children.

    Science.gov (United States)

    Serpanos, Yula C; Senzer, Deborah; Renne, Brittany; Langer, Rebecca; Hoffman, Roxanne

    2015-09-01

    This study was conducted to investigate the efficacy of routine screening for high-frequency hearing loss (HFHL) including 3000, 6000, and 8000 Hz frequencies with conventional test frequencies (1000, 2000, and 4000 Hz) in adults and children in a university outreach program. Screening outcomes were examined in 2 cohorts of adults (Cohort 1, N = 315, M = 66.2 years; Cohort 2, N = 67, M = 68.3 years) and children (Cohort 1, N = 177, M = 6.5 years; Cohort 2, N = 57, M = 6.9 years) with a high-frequency screen protocol (1000-8000 Hz at 25 dB HL for adults and 20 dB HL for children) using supra-aural headphones. A rescreen was conducted in Cohort 2 with a modified protocol using insert earphones and monitored ambient noise levels. Average total test time significantly increased (p headphones. Screening for HFHL should include insert earphones in order to prevent potential errors, particularly at 6000 and 8000 Hz.

  14. Highly confined low-loss plasmons in graphene-boron nitride heterostructures

    Science.gov (United States)

    Woessner, Achim; Lundeberg, Mark B.; Gao, Yuanda; Principi, Alessandro; Alonso-González, Pablo; Carrega, Matteo; Watanabe, Kenji; Taniguchi, Takashi; Vignale, Giovanni; Polini, Marco; Hone, James; Hillenbrand, Rainer; Koppens, Frank H. L.

    2015-04-01

    Graphene plasmons were predicted to possess simultaneous ultrastrong field confinement and very low damping, enabling new classes of devices for deep-subwavelength metamaterials, single-photon nonlinearities, extraordinarily strong light-matter interactions and nano-optoelectronic switches. Although all of these great prospects require low damping, thus far strong plasmon damping has been observed, with both impurity scattering and many-body effects in graphene proposed as possible explanations. With the advent of van der Waals heterostructures, new methods have been developed to integrate graphene with other atomically flat materials. In this Article we exploit near-field microscopy to image propagating plasmons in high-quality graphene encapsulated between two films of hexagonal boron nitride (h-BN). We determine the dispersion and plasmon damping in real space. We find unprecedentedly low plasmon damping combined with strong field confinement and confirm the high uniformity of this plasmonic medium. The main damping channels are attributed to intrinsic thermal phonons in the graphene and dielectric losses in the h-BN. The observation and in-depth understanding of low plasmon damping is the key to the development of graphene nanophotonic and nano-optoelectronic devices.

  15. Neglecting rice milling yield and quality underestimates economic losses from high-temperature stress.

    Directory of Open Access Journals (Sweden)

    Nathaniel B Lyman

    Full Text Available Future increases in global surface temperature threaten those worldwide who depend on rice production for their livelihoods and food security. Past analyses of high-temperature stress on rice production have focused on paddy yield and have failed to account for the detrimental impact of high temperatures on milling quality outcomes, which ultimately determine edible (marketable rice yield and market value. Using genotype specific rice yield and milling quality data on six common rice varieties from Arkansas, USA, combined with on-site, half-hourly and daily temperature observations, we show a nonlinear effect of high-temperature stress exposure on yield and milling quality. A 1 °C increase in average growing season temperature reduces paddy yield by 6.2%, total milled rice yield by 7.1% to 8.0%, head rice yield by 9.0% to 13.8%, and total milling revenue by 8.1% to 11.0%, across genotypes. Our results indicate that failure to account for changes in milling quality leads to understatement of the impacts of high temperatures on rice production outcomes. These dramatic losses result from reduced paddy yield and increased percentages of chalky and broken kernels, which together decrease the quantity and market value of milled rice. Recently published estimates show paddy yield reductions of up to 10% across the major rice-producing regions of South and Southeast Asia due to rising temperatures. The results of our study suggest that the often-cited 10% figure underestimates the economic implications of climate change for rice producers, thus potentially threatening future food security for global rice producers and consumers.

  16. Noise-induced hearing loss: A possible marker for high blood pressure in older noise-exposed populations

    Energy Technology Data Exchange (ETDEWEB)

    Talbott, E.O.; Findlay, R.C.; Kuller, L.H.; Lenkner, L.A.; Matthews, K.A.; Day, R.D.; Ishii, E.K. (Univ. of Pittsburgh, PA (USA))

    1990-08-01

    The present study assessed the relationships among occupational noise exposure, noise-induced hearing loss, and high blood pressure. The study population consisted of 245 retired metal assembly workers from Pittsburgh aged 56 to 68 with chronic noise exposure of 30 or more years at greater than or equal to 89 dBA. Results of the audiometric testing indicated 52% of the younger workers (ages 56 to 63) have severe noise-induced hearing loss (greater than or equal to 65 dBA loss at 3, 4, or 6 kHz) and 67% of older workers (ages 64 to 68). Body mass index and alcohol intake were significantly related to systolic and diastolic blood pressure. Among older men, there was a marginally significant increased prevalence of high blood pressure (greater than or equal to 90 mm diastolic or taking blood pressure medicine) among those with severe noise-induced hearing loss (P = .05). Moreover, another measure of hearing loss at high frequencies, speech discrimination score in noise (measured in the better ear), referred to as the W-22 MAX score, was also found to be related to the prevalence of high blood pressure in the older (64 to 68) age group (P less than .05). Multiple regression analysis revealed W-22 MAX and severe noise-induced hearing loss were independent predictors of hypertension in the older, but not in the younger group of retired workers.

  17. Pushbroom Stereo for High-Speed Navigation in Cluttered Environments

    OpenAIRE

    Barry, Andrew J.; Tedrake, Russ

    2014-01-01

    We present a novel stereo vision algorithm that is capable of obstacle detection on a mobile ARM processor at 120 frames per second. Our system performs a subset of standard block-matching stereo processing, searching only for obstacles at a single depth. By using an onboard IMU and state-estimator, we can recover the position of obstacles at all other depths, building and updating a local depth-map at framerate. Here, we describe both the algorithm and our implementation on a high-speed, sma...

  18. Achieving High Resolution Timer Events in Virtualized Environment.

    Science.gov (United States)

    Adamczyk, Blazej; Chydzinski, Andrzej

    2015-01-01

    Virtual Machine Monitors (VMM) have become popular in different application areas. Some applications may require to generate the timer events with high resolution and precision. This however may be challenging due to the complexity of VMMs. In this paper we focus on the timer functionality provided by five different VMMs-Xen, KVM, Qemu, VirtualBox and VMWare. Firstly, we evaluate resolutions and precisions of their timer events. Apparently, provided resolutions and precisions are far too low for some applications (e.g. networking applications with the quality of service). Then, using Xen virtualization we demonstrate the improved timer design that greatly enhances both the resolution and precision of achieved timer events.

  19. Fast Timing for High-Rate Environments with Micromegas

    CERN Document Server

    Papaevangelou, Thomas; Ferrer-Ribas, Esther; Giomataris, Ioannis; Godinot, Cyprien; Gonzalez Diaz, Diego; Gustavsson, Thomas; Kebbiri, Mariam; Oliveri, Eraldo; Resnati, Filippo; Ropelewski, Leszek; Tsiledakis, Georgios; Veenhof, Rob; White, Sebastian

    2016-01-01

    The current state of the art in fast timing resolution for existing experiments is of the order of 100 ps on the time of arrival of both charged particles and electromagnetic showers. Current R&D on charged particle timing is approaching the level of 10 ps but is not primarily directed at sustained performance at high rates and under high radiation (as would be needed for HL-LHC pileup mitigation). We demonstrate a Micromegas based solution to reach this level of performance. The Micromegas acts as a photomultiplier coupled to a Cerenkov-radiator front window, which produces sufficient UV photons to convert the ~100 ps single-photoelectron jitter into a timing response of the order of 10-20 ps per incident charged particle. A prototype has been built in order to demonstrate this performance. The first laboratory tests with a pico-second laser have shown a time resolution of the order of 27 ps for ~50 primary photoelectrons, using a bulk Micromegas readout.

  20. Fast Timing for High-Rate Environments with Micromegas

    Directory of Open Access Journals (Sweden)

    Papaevangelou Thomas

    2018-01-01

    Full Text Available The current state of the art in fast timing resolution for existing experiments is of the order of 100 ps on the time of arrival of both charged particles and electromagnetic showers. Current R&D on charged particle timing is approaching the level of 10 ps but is not primarily directed at sustained performance at high rates and under high radiation (as would be needed for HL-LHC pileup mitigation. We demonstrate aMicromegas based solution to reach this level of performance. The Micromegas acts as a photomultiplier coupled to a Cerenkovradiator front window, which produces sufficient UV photons to convert the ∼100 ps single-photoelectron jitter into a timing response of the order of 10-20 ps per incident charged particle. A prototype has been built in order to demonstrate this performance. The first laboratory tests with a pico-second laser have shown a time resolution of the order of 27 ps for ∼50 primary photoelectrons, using a bulk Micromegas readout.

  1. Spin-sprayed ferrite films with high resistivity and high-frequency magnetic loss for GHz conducted noise suppressors

    Energy Technology Data Exchange (ETDEWEB)

    Subramani, A.K. [Materials and Structures Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta, Midori, Yokohama (Japan)], E-mail: subramani.aa@m.titech.ac.jp; Matsushita, N. [Materials and Structures Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta, Midori, Yokohama (Japan)], E-mail: matsushita@msl.titech.ac.jp; Watanabe, T. [Materials and Structures Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta, Midori, Yokohama (Japan); Tada, M.; Abe, M. [Department of Physical Electronics, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro, Tokyo 152-8552 (Japan); Kondo, K. [NEC Tokin Corporation, 6-7-1 Koriyama, Taihaku-ku, Sendai, Miyagi 982-8510 (Japan); Yoshimura, M. [Materials and Structures Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta, Midori, Yokohama (Japan)

    2008-02-25

    In the present study, crystallized ferrite (an intermediate between Fe{sub 3}O{sub 4} and {gamma}-Fe{sub 2}O{sub 3}) films prepared by spin-spray technique exhibited strong magnetic losses at high frequencies and are applicable as GHz conducted noise suppressors. The reaction (metal ions) and oxidizing (pH buffers and oxidizing agent) solutions were separately sprayed onto the substrates (90 deg. C) mounted on a rotating disc. Two types of films were prepared on the basis of the different oxidizing solutions; CH{sub 3}COONa + NaNO{sub 2} in the case of film-A and CH{sub 3}COONa + (NH{sub 4}){sub 2}CO{sub 3} + NaNO{sub 2} + NaOH for film-B. The as-prepared films were heat-treated under a condition similar to that of the reflow soldering process (265 deg. C). The effects of the preparation conditions and film morphology on the electrical and magnetic properties before and after the heat treatment were studied. The results revealed that film-B had a relatively smaller initial permeability ({mu}') compared to film-A. However, it had a high-imaginary permeability ({mu}''), resonance frequency (f{sub r}) and surface resistivity ({rho}{sub s}) even after heat treatment. Also, the noise suppressing properties of film-B were relatively good, hence ideal for use as conducted noise suppressors.

  2. Towards an optimum silicon heterojunction solar cell configuration for high temperature and high light intensity environment

    KAUST Repository

    Abdallah, Amir

    2017-09-22

    We report on the performance of Silicon Heterojunction (SHJ) solar cell under high operating temperature and varying irradiance conditions typical to desert environment. In order to define the best solar cell configuration that resist high operating temperature conditions, two different intrinsic passivation layers were tested, namely, an intrinsic amorphous silicon a-SiO:H with CO/SiH ratio of 0.4 and a-SiOx:H with CO/SiH ratio of 0.8, and the obtained performance were compared with those of a standard SHJ cell configuration having a-Si:H passivation layer. Our results showed how the short circuit current density J, and fill factor FF temperature-dependency are impacted by the cell\\'s configuration. While the short circuit current density J for cells with a-SiO:H layers was found to improve as compared with that of standard a-Si:H layer, introducing the intrinsic amorphous silicon oxide (a-SiO:H) layer with CO/SiH ratio of 0.8 has resulted in a reduction of the FF at room temperature due to hindering the carrier transport by the band structure. Besides, this FF was found to improve as the temperature increases from 15 to 45°C, thus, a positive FF temperature coefficient.

  3. Achieving High Resolution Timer Events in Virtualized Environment.

    Directory of Open Access Journals (Sweden)

    Blazej Adamczyk

    Full Text Available Virtual Machine Monitors (VMM have become popular in different application areas. Some applications may require to generate the timer events with high resolution and precision. This however may be challenging due to the complexity of VMMs. In this paper we focus on the timer functionality provided by five different VMMs-Xen, KVM, Qemu, VirtualBox and VMWare. Firstly, we evaluate resolutions and precisions of their timer events. Apparently, provided resolutions and precisions are far too low for some applications (e.g. networking applications with the quality of service. Then, using Xen virtualization we demonstrate the improved timer design that greatly enhances both the resolution and precision of achieved timer events.

  4. INNOVATIVE TEACHING BUSINESS ENVIRONMENT AS A BASIS FOR THE FORMATION OF ENTREPRENEURIAL COMPETENCE IN HIGH SCHOOL

    Directory of Open Access Journals (Sweden)

    Natalya Nikolaevna Masyuk

    2015-01-01

    Full Text Available Developing entrepreneurial competencies for high school students is only possible as a result of the creation of such an educational environment that will play such a relationship between training firms, which would be as realistic as possible. To this end, the university created an innovative educational business environment.Objective: To create an organizational model and algorithm innovative educational business environment.Method or the methodology of the work: desk research.Results: The algorithm of the organizational procedures for creating innovative business environment of high school.Scope results: management, marketing, entrepreneurship.

  5. Calcium aluminate cement hydration in a high alkalinity environment

    Directory of Open Access Journals (Sweden)

    Palomo, Á.

    2009-03-01

    Full Text Available The present paper forms part of a broader research project that aims primarily to devise new cementitious products via the alkali activation of silico-aluminous materials. This work addresses the possibility of using small percentages of calcium aluminate cement (CAC as a source of reactive aluminium. For this reason, a preliminary review was needed of the behaviour of CACs in highly alkaline media (2, 8 and 12M NaOH solutions. Two, 28- and 180-day mechanical strength was determined and the reaction products were characterized with XRD and FTIR. The water-hydrated CAC was used as the control.The results obtained showed that CAC hardening took place much more slowly in highly alkaline media than in water. Nonetheless, the 28-day compressive strength obtained, ≥80MPa. As main reaction products, to ambient temperature and from the two days of cured, cubic aluminate C3AH6, and AH3 polymorphs are formed, instead of the usual hexagonal aluminatos (CAH10 and C2AH8 that are formed in the normal hydrate with water.El presente trabajo forma parte de una amplia investigación cuyo objetivo principal es el de elaborar nuevos materiales con propiedades cementantes mediante la activación alcalina de materiales de naturaleza silito-aluminosa. En estos estudios se contempla la posibilidad de utilizar pequeños porcentajes de cemento de aluminato de calcio (CAC como fuente de aluminio reactivo. Por ello inicialmente se ha estudiado el comportamiento de los CAC en medios fuertemente alcalinos (disoluciones de NaOH 2M, 8M y 12M. Se determinaron las resistencias mecánicas a 2, 28 y 180 días y se realizó una caracterización de los productos de reacción formados por DRX, FTIR. Como sistema de referencia se consideró la hidratación del CAC con agua.Los resultados obtenidos muestran que en medios fuertemente alcalinos se retrasan los procesos de rápido endurecimiento de CAC con agua. No obstante a 28 días se obtienen valores de resistencia a compresión

  6. Dispersion-modulation by high material loss in microstructured polymer optical fibers

    DEFF Research Database (Denmark)

    Frosz, Michael Henoch

    2009-01-01

    The influence of strong loss peaks on the dispersion (through the Kramers-Kronig relations) of a nonlinear waveguide is investigated theore­ti­cally. It is found specifically for degenerate four-wave mixing in a poly(methyl methacrylate) microstructured polymer optical fiber that the loss...

  7. Measuring ac-loss in high temperature superconducting cable-conductors using four probe methods

    DEFF Research Database (Denmark)

    Kühle (fratrådt), Anders Van Der Aa; Træholt, Chresten; Olsen, Søren Krüger

    1999-01-01

    Measuring the ac-loss of superconducting cable conductors have many aspects in common with measuring the ac-loss of single superconducting tapes. In a cable conductor all tapes are connected to each other and to the test circuit through normal metal joints in each end. This makes such measurements...

  8. High CpG island methylation of p16 gene and loss of p16 protein ...

    Indian Academy of Sciences (India)

    SI-JU GAO

    examined owning to the limitation of biopsies. Accordingly, future studies on the association of p16 methylation and ToF incidence are required. In conclusion, we detected a novel loss of p16 expression in ToF patients and showed that p16 loss correlates with CpG island methylation of p16 gene. For the first time, our study.

  9. Diamond and silicon pixel detectors in high radiation environments

    Energy Technology Data Exchange (ETDEWEB)

    Tsung, Jieh-Wen

    2012-10-15

    Diamond pixel detector is a promising candidate for tracking of collider experiments because of the good radiation tolerance of diamond. The diamond pixel detector must withstand the radiation damage from 10{sup 16} particles per cm{sup 2}, which is the expected total fluence in High Luminosity Large Hadron Collider. The performance of diamond and silicon pixel detectors are evaluated in this research in terms of the signal-to-noise ratio (SNR). Single-crystal diamond pixel detectors with the most recent readout chip ATLAS FE-I4 are produced and characterized. Based on the results of the measurement, the SNR of diamond pixel detector is evaluated as a function of radiation fluence, and compared to that of planar-silicon ones. The deterioration of signal due to radiation damage is formulated using the mean free path of charge carriers in the sensor. The noise from the pixel readout circuit is simulated and calculated with leakage current and input capacitance to the amplifier as important parameters. The measured SNR shows good agreement with the calculated and simulated results, proving that the performance of diamond pixel detectors can exceed the silicon ones if the particle fluence is more than 10{sup 15} particles per cm{sup 2}.

  10. AC Losses and Their Thermal Effect in High-Temperature Superconducting Machines

    DEFF Research Database (Denmark)

    Song, Xiaowei (Andy); Mijatovic, Nenad; Zou, Shengnan

    2016-01-01

    In transient operations or fault conditions, hightemperature superconducting (HTS) machines suffer ac losses, which have an influence on the thermal stability of superconducting windings. In this paper, a method to calculate ac losses and their thermal effect in HTS machines is presented....... The method consists of three submodels that are coupled only in one direction. The magnetic field distribution is first solved in a machine model, assuming a uniform current distribution in HTS windings. The magnetic fields on the boundaries are then used as inputs for an ac loss model that has a homogeneous...... approximation and solves the H formulation. Afterward, the computed ac losses are considered as the heat source in a thermal model to study the temperature profile in HTS windings. The method proposed is able to evaluate ac losses and their thermal effect, thus providing a reference to design an HTS machine...

  11. Phase-space Analysis in the Group and Cluster Environment: Time Since Infall and Tidal Mass Loss

    Science.gov (United States)

    Rhee, Jinsu; Smith, Rory; Choi, Hoseung; Yi, Sukyoung K.; Jaffé, Yara; Candlish, Graeme; Sánchez-Jánssen, Ruben

    2017-07-01

    Using the latest cosmological hydrodynamic N-body simulations of groups and clusters, we study how location in phase-space coordinates at z = 0 can provide information on environmental effects acting in clusters. We confirm the results of previous authors showing that galaxies tend to follow a typical path in phase-space as they settle into the cluster potential. As such, different regions of phase-space can be associated with different times since first infalling into the cluster. However, in addition, we see a clear trend between total mass loss due to cluster tides and time since infall. Thus, we find location in phase-space provides information on both infall time and tidal mass loss. We find the predictive power of phase-space diagrams remains even when projected quantities are used (I.e., line of sight velocities, and projected distances from the cluster). We provide figures that can be directly compared with observed samples of cluster galaxies and we also provide the data used to make them as supplementary data to encourage the use of phase-space diagrams as a tool to understand cluster environmental effects. We find that our results depend very weakly on galaxy mass or host mass, so the predictions in our phase-space diagrams can be applied to groups or clusters alike, or to galaxy populations from dwarfs up to giants.

  12. Impact of Maine’s Statewide Nutrition Policy on High School Food Environments

    OpenAIRE

    Whatley Blum, Janet E.; Beaudoin, Christina M; O'Brien, Liam M.; Polacsek, Michele; Harris, David E.; O'Rourke, Karen A.

    2010-01-01

    Introduction We assessed the effect on the food environments of public high schools of Maine's statewide nutrition policy (Chapter 51), which banned "foods of minimal nutritional value" (FMNV) in public high schools that participated in federally funded meal programs. We documented allowable exceptions to the policy and describe the school food environments. Methods We mailed surveys to 89 high school food-service directors to assess availability pre–Chapter 51 and post–Chapter 51 of soda, ot...

  13. Analysing the physics learning environment of visually impaired students in high schools

    Science.gov (United States)

    Toenders, Frank G. C.; de Putter-Smits, Lesley G. A.; Sanders, Wendy T. M.; den Brok, Perry

    2017-07-01

    Although visually impaired students attend regular high school, their enrolment in advanced science classes is dramatically low. In our research we evaluated the physics learning environment of a blind high school student in a regular Dutch high school. For visually impaired students to grasp physics concepts, time and additional materials to support the learning process are key. Time for teachers to develop teaching methods for such students is scarce. Suggestions for changes to the learning environment and of materials used are given.

  14. Short-term, daily exposure to cold temperature may be an efficient way to prevent muscle atrophy and bone loss in a microgravity environment

    Science.gov (United States)

    Deng, Claudia; Wang, Ping; Zhang, Xiangming; Wang, Ya

    2015-04-01

    Microgravity induces less pressure on muscle/bone, which is a major reason for muscle atrophy as well as bone loss. Currently, physical exercise is the only countermeasure used consistently in the U.S. human space program to counteract the microgravity-induced skeletal muscle atrophy and bone loss. However, the routinely almost daily time commitment is significant and represents a potential risk to the accomplishment of other mission operational tasks. Therefore, development of more efficient exercise programs (with less time) to prevent astronauts from muscle atrophy and bone loss are needed. Consider the two types of muscle contraction: exercising forces muscle contraction and prevents microgravity-induced muscle atrophy/bone loss, which is a voluntary response through the motor nervous system; and cold temperature exposure-induced muscle contraction is an involuntary response through the vegetative nervous system, we formed a new hypothesis. The main purpose of this pilot study was to test our hypothesis that exercise at 4 °C is more efficient than at room temperature to prevent microgravity-induced muscle atrophy/bone loss and, consequently reduces physical exercise time. Twenty mice were divided into two groups with or without daily short-term (10 min × 2, at 12 h interval) cold temperature (4 °C) exposure for 30 days. The whole bodyweight, muscle strength and bone density were measured after terminating the experiments. The results from the one-month pilot study support our hypothesis and suggest that it would be reasonable to use more mice, in a microgravity environment and observe for a longer period to obtain a conclusion. We believe that the results from such a study will help to develop efficient exercise, which will finally benefit astronauts' heath and NASA's missions.

  15. Detailed study of parton energy loss via measurement of fractional momentum loss of high pT hadrons in heavy ion collisions

    Science.gov (United States)

    Sakaguchi, Takao; PHENIX Collaboration

    2017-02-01

    PHENIX measurement of the fractional momentum loss (δp T/p T) of high p T identified hadrons are presented. The δp T/p T of high p T π 0 which are computed from 39 GeV Au+Au up to 2.76 TeV Pb+Pb are found to vary by a factor of six. We plotted the δp T/p T against several global variables, N part, N qp and dN ch/dη, and found global features. It was found that 200 GeV Au+Au points are merging into the central 2.76 TeV Pb+Pb points when plotting δp T/p T against dN ch/dη.

  16. Energy-Based Tetrahedron Sensor for High-Temperature, High-Pressure Environments

    Science.gov (United States)

    Gee, Kent L.; Sommerfeldt, Scott D.; Blotter, Jonathan D.

    2012-01-01

    An acoustic energy-based probe has been developed that incorporates multiple acoustic sensing elements in order to obtain the acoustic pressure and three-dimensional acoustic particle velocity. With these quantities, the user can obtain various energy-based quantities, including acoustic energy density, acoustic intensity, and acoustic impedance. In this specific development, the probe has been designed to operate in an environment characterized by high temperatures and high pressures as is found in the close vicinity of rocket plumes. Given these capabilities, the probe is designed to be used to investigate the acoustic conditions within the plume of a rocket engine or jet engine to facilitate greater understanding of the noise generation mechanisms in those plumes. The probe features sensors mounted inside a solid sphere. The associated electronics for the probe are contained within the sphere and the associated handle for the probe. More importantly, the design of the probe has desirable properties that reduce the bias errors associated with determining the acoustic pressure and velocity using finite sum and difference techniques. The diameter of the probe dictates the lower and upper operating frequencies for the probe, where accurate measurements can be acquired. The current probe design implements a sphere diameter of 1 in. (2.5 cm), which limits the upper operating frequency to about 4.5 kHz. The sensors are operational up to much higher frequencies, and could be used to acquire pressure data at higher frequencies, but the energy-based measurements are limited to that upper frequency. Larger or smaller spherical probes could be designed to go to lower or higher frequency range

  17. L-ascorbic acid losses in Kenyan vegetables during cooking as determined by high performance liquid chromatography

    Directory of Open Access Journals (Sweden)

    N.M.N. Wekesa

    2001-06-01

    Full Text Available The loss of L-ascorbic acid (L-AA in 14 different cooked local vegetables found in Nairobi markets was determined by high performance liquid chromatography. The effect of quantity of water on the loss of L-AA during cooking was studied with cowpea leaves. It was found that more L-AA was lost when larger amount of water was used than when smaller amount was used. The effect of the sharpness of the knife on the loss of L-AA was studied with spinach. It was found that more loss of L-AA occurred when a blunt (edge thickness 0.08 cm knife was used for cutting the vegetables than when a sharp knife (edge thickness 0.04 cm was used during cooking. L-AA was also determined when vegetables were cooked in different size pieces (surface are >1 cm2

  18. Causes of visual acuity loss among patients with AIDS and cytomegalovirus retinitis in the era of highly active antiretroviral therapy.

    Science.gov (United States)

    Thorne, Jennifer E; Jabs, Douglas A; Kempen, John H; Holbrook, Janet T; Nichols, Charles; Meinert, Curtis L

    2006-08-01

    To quantitate the frequencies of the common causes of visual acuity loss for patients with AIDS and cytomegalovirus (CMV) retinitis in the era of highly active antiretroviral therapy (HAART). Multicenter prospective observational study. Three hundred seventy-nine patients (494 eyes) with CMV retinitis. Follow-up every 3 months with medical history, ophthalmologic examination, and laboratory testing. Loss of visual acuity across the 20/50 or worse and 20/200 or worse thresholds and doubling of the visual angle; frequencies of causes of such vision loss. Overall, involvement of the posterior pole with CMV retinitis (zone 1 retinitis) accounted for approximately one half of incident visual acuity loss of 20/50 or worse, 20/200 or worse, and of doubling of the visual angle. Cataract and retinitis-related retinal detachment were the second and third most common causes of vision loss, accounting for 22% to 33% and 13% to 20% of vision loss for the 3 outcomes, respectively. In subset analysis, cataract and cystoid macular edema (CME) accounted for approximately 50% of incident vision loss in eyes of patients with longstanding CMV retinitis and immune recovery at baseline, but these complications accounted for visual impairment (20/50 or worse vision) and 42% of eyes developing legal blindness (20/200 or worse vision) at 12 months after diagnosis of the retinal detachment. In the HAART era, zone 1 involvement and retinal detachment remain the most common causes of visual acuity loss among patients with CMV retinitis. Cataract and CME also are common causes of loss of visual acuity, primarily in those patients with HAART-induced immune recovery.

  19. Low Loss and Highly Birefringent Hollow-Core Photonic Crystal Fiber

    DEFF Research Database (Denmark)

    Roberts, P. John; Williams, D.P.; Mangan, Brian J.

    2006-01-01

    A hollow-core photonic crystal fiber design is proposed which enables both low-loss and polarization-maintained signal propagation. The design relies on an arrangement of antiresonant features positioned on the glass ring that surrounds the air core.......A hollow-core photonic crystal fiber design is proposed which enables both low-loss and polarization-maintained signal propagation. The design relies on an arrangement of antiresonant features positioned on the glass ring that surrounds the air core....

  20. Drainage in Shallow Peatlands of Marginal Upland Landscapes: DOC Losses from High Flow Events

    Science.gov (United States)

    Grand-Clement, E.; Anderson, K.; Luscombe, D.; Gatis, N.; Benaud, P.; Brazier, R.

    2013-12-01

    Peatlands are widely represented in northern Europe, especially in the UK. In the South West of England (i.e. Exmoor, Dartmoor and Bodmin moors), climate change puts their existence under threat: according to recent modelling work, marginal peatlands are highly vulnerable to future temperature and precipitation change and are likely to be the first to disappear from as early as 2050. Additionally, peat cutting and intensive drainage for agricultural reclamation in the 19th and 20th century, have modified the hydrological behaviour of these shallow peatlands and dried out the upper layers, causing oxidation, erosion and vegetation change. Such anthropogenic interventions directly impact on the storage of carbon, but also the provision of other ecosystem services, such as the supply of drinking water, and the support of specific and rare habitats. Large restoration programs involving the blocking of drainage ditches are currently under way throughout the UK but, to date, little is known about the consequences of such management approaches on overall Carbon stocks, and whether the restoration can revert ecosystems back to a state similar to that of undisturbed peatlands. In this context, Exmoor is particularly vulnerable due to its location at the southernmost margin of the UK peatlands' geographical extent, and its dense network of drainage ditches putting pressure on already very shallow peat resources. We hypothesise that monitoring of these peatlands may provide an ';early warning system' for climatic impacts that could affect more northerly sites in years to come, as climates change more significantly. The aim of this study is to look at the current impact of peatland degradation on water quality on Exmoor during rainfall-runoff events. Our experimental approach employs detailed, high resolution monitoring of selected ditches that are representative of damaged conditions on Exmoor, from small- (30 x 30cm ditches) through medium- (50x50cm), large- (1-2m ditches

  1. High dietary calcium intake does not counteract disuse-induced bone loss

    Science.gov (United States)

    Baecker, N.; Boese, A.; Smith, S. M.; Heer, M.

    Reduction of mechanical stress on bone inhibits osteoblast-mediated bone formation, increases osteoclast-mediated bone resorption, and leads to what has been called disuse osteoporosis. Prolonged therapeutic bed rest, immobilization and space flight are common causes of disuse osteoporosis. There are sufficient data supporting the use of calcium in combination with vitamin D in the prevention and treatment of postmenopausal osteoporosis. In our study we examined the potential of high dietary calcium intake as a nutrition therapy for disuse-induced bone loss during head-down bed rest in healthy young men. In 2 identical metabolic ward, head-down bed rest (HDBR) experiments (crossover design), we studied the effect of high dietary calcium intake (2000 mg/d) in comparison to the recommended calcium intake of 1000 mg/d on markers of bone turnover. Experiment A (EA) was a 6-day randomized, controlled HDBR study. Experiment B (EB) was a 14-day randomized, controlled HDBR study. In both experiments, the test subjects stayed under well-controlled environmental conditions in our metabolic ward. Subjects' diets in the relevant study phases (HDBR versus Ambulatory Control) of EA and EB were identical except for the calcium intake. The subjects obtained 2000 mg/d Calcium in EA and 2000 mg/d in EB. Blood was drawn at baseline, before entering the relevant intervention period, on day 5 in study EA, and on days 6, 11 and 14 in study EB. Serum calcium, bone formation markers - Procollagen-I-C-Propeptide (PICP) and bone alkaline phosphatase (bAP) were analyzed in serum. 24h-urine was collected throughout the studies for determination of the excretion of calcium (UCaV) and a bone resorption marker, C-terminal telopeptide of collagen type I (UCTX). In both studies, serum calcium levels were unchanged. PICP tended to decrease in EA (p=0.08). In EB PICP decreased significantly over time (p=0.003) in both the control and HDBR periods, and tended to further decrease in the HDBR period (p

  2. Cacao Cultivation under Diverse Shade Tree Cover Allows High Carbon Storage and Sequestration without Yield Losses.

    Science.gov (United States)

    Abou Rajab, Yasmin; Leuschner, Christoph; Barus, Henry; Tjoa, Aiyen; Hertel, Dietrich

    2016-01-01

    One of the main drivers of tropical forest loss is their conversion to oil palm, soy or cacao plantations with low biodiversity and greatly reduced carbon storage. Southeast Asian cacao plantations are often established under shade tree cover, but are later converted to non-shaded monocultures to avoid resource competition. We compared three co-occurring cacao cultivation systems (3 replicate stands each) with different shade intensity (non-shaded monoculture, cacao with the legume Gliricidia sepium shade trees, and cacao with several shade tree species) in Sulawesi (Indonesia) with respect to above- and belowground biomass and productivity, and cacao bean yield. Total biomass C stocks (above- and belowground) increased fivefold from the monoculture to the multi-shade tree system (from 11 to 57 Mg ha-1), total net primary production rose twofold (from 9 to 18 Mg C ha-1 yr-1). This increase was associated with a 6fold increase in aboveground biomass, but only a 3.5fold increase in root biomass, indicating a clear shift in C allocation to aboveground tree organs with increasing shade for both cacao and shade trees. Despite a canopy cover increase from 50 to 93%, cacao bean yield remained invariant across the systems (variation: 1.1-1.2 Mg C ha-1 yr-1). The monocultures had a twice as rapid leaf turnover suggesting that shading reduces the exposure of cacao to atmospheric drought, probably resulting in greater leaf longevity. Thus, contrary to general belief, cacao bean yield does not necessarily decrease under shading which seems to reduce physical stress. If planned properly, cacao plantations under a shade tree cover allow combining high yield with benefits for carbon sequestration and storage, production system stability under stress, and higher levels of animal and plant diversity.

  3. Pediatric Loss of Control Eating and High-Sensitivity C-Reactive Protein Concentrations.

    Science.gov (United States)

    Shank, Lisa M; Tanofsky-Kraff, Marian; Kelly, Nichole R; Schvey, Natasha A; Marwitz, Shannon E; Mehari, Rim D; Brady, Sheila M; Demidowich, Andrew P; Broadney, Miranda M; Galescu, Ovidiu A; Pickworth, Courtney K; Yanovski, Susan Z; Yanovski, Jack A

    2017-02-01

    Loss of control (LOC) eating in youth is associated with excess body weight and adiposity. After adjusting for fat mass, youth with LOC eating have higher blood pressure and higher low-density lipoprotein cholesterol compared to youth without LOC eating. Increased inflammation may account for this relationship, although few data have examined this hypothesis. Therefore, this study explored the association between LOC eating and high-sensitivity C-reactive protein (hsCRP), a marker of inflammation. We investigated hsCRP concentrations in relation to LOC eating in a convenience sample of 194 youth (age 14.3 ± 2.1 years; 63.9% female; BMI-z 1.64 ± 1.06). The presence of LOC eating in the past month was assessed by the Eating Disorder Examination interview. Serum hsCRP was measured by enzyme-linked immunosorbent assay. Adiposity was measured by air displacement plethysmography or dual-energy x-ray absorptiometry. We compared hsCRP in those with and without LOC eating in analyses accounting for sex, adiposity, height, depressive symptoms, and eating psychopathology. Youth with LOC eating had significantly greater hsCRP than youth without LOC eating (p = 0.02), after accounting for all covariates. The number of LOC eating episodes in the past month was positively associated with hsCRP (p = 0.01). The relationship between LOC eating and hsCRP was not mediated by depressive symptoms or eating psychopathology (ps > 0.05). Youth with disinhibited eating may manifest increased chronic inflammation. Those with LOC eating may be an important subgroup at risk for adverse health outcomes associated with both chronic inflammation and obesity. Future research should examine whether hsCRP concentrations mediate the relationship between LOC eating and its association with cardiometabolic risk.

  4. High polyphenol, low probiotic diet for weight loss because of intestinal microbiota interaction.

    Science.gov (United States)

    Rastmanesh, Reza

    2011-01-15

    The relative proportion of Bacteroidetes to Firmicutes is decreased in obese people. This imbalance in gut microbiota generates signals controlling the expression of genes by the epithelial intestinal cells. Both dairy and non-dairy probiotics increase body weight, reportedly through Lactobacillus species growth in the gut. On the other hand, daily intake of some fruits and drinks such as three apples or three pears or grapefruit, or green tea, which all are rich in polyphenols, can significantly reduce body weight in obese people. Metabolism of polyphenols by microbiota involves the cleavage of glycosidic linkages. Glycans, which are the product of glycosidic cleavage, are necessary for survival of the intestinal microbiota as a nutrient foundation. There are two pivotal points: (i) Firmicutes possess a disproportionately smaller number of glycan-degrading enzymes than Bacteroidetes, (ii) Firmicutes are more repressed than the Bacteroidetes by phenolic compounds' antimicrobial properties. The Bacteroidetes community prevails following dietary polyphenol intake and its fermentation to phenolic compounds, due to having more glycan-degrading enzymes, so this may thus be a mechanism by which dietary polyphenols exert their weight lowering effect. I suggest that future studies utilize clone libraries and fingerprinting techniques enabling identification of the composition and community structure of the microbiota, and dot blot hybridization or fluorescent in situ hybridization to analyze abundance of particular taxa in obese and individuals. A supplementation with polyphenols with high bioavailability in obese individuals with higher Firmicutes/Bacteroides community ratio phenotype, when associated to a probiotic restricted diet, is proposed for weight loss; this hypothesis could have relevant implication in planning a successful dietary regimen and/or neutraceutical/pharmaceutical preparations for achieving and maintaining a normal body weight in obese individuals

  5. Performance of high performance concrete (HPC) in low pH and sulfate environment : [technical summary].

    Science.gov (United States)

    2013-01-01

    High-performance concrete (HPC) refers to any concrete formulation with enhanced characteristics, compared to normal concrete. One might think this refers to strength, but in Florida, the HPC standard emphasizes withstanding aggressive environments, ...

  6. The plastid genome of Najas flexilis: adaptation to submersed environments is accompanied by the complete loss of the NDH complex in an aquatic angiosperm.

    Directory of Open Access Journals (Sweden)

    Elena L Peredo

    Full Text Available The re-colonization of aquatic habitats by angiosperms has presented a difficult challenge to plants whose long evolutionary history primarily reflects adaptations to terrestrial conditions. Many aquatics must complete vital stages of their life cycle on the water surface by means of floating or emergent leaves and flowers. Only a few species, mainly within the order Alismatales, are able to complete all aspects of their life cycle including pollination, entirely underwater. Water-pollinated Alismatales include seagrasses and water nymphs (Najas, the latter being the only freshwater genus in the family Hydrocharitaceae with subsurface water-pollination. We have determined the complete nucleotide sequence of the plastid genome of Najas flexilis. The plastid genome of N. flexilis is a circular AT-rich DNA molecule of 156 kb, which displays a quadripartite structure with two inverted repeats (IR separating the large single copy (LSC from the small single copy (SSC regions. In N. flexilis, as in other Alismatales, the rps19 and trnH genes are localized in the LSC region instead of within the IR regions as in other monocots. However, the N. flexilis plastid genome presents some anomalous modifications. The size of the SSC region is only one third of that reported for closely related species. The number of genes in the plastid is considerably less. Both features are due to loss of the eleven ndh genes in the Najas flexilis plastid. In angiosperms, the absence of ndh genes has been related mainly to the loss of photosynthetic function in parasitic plants. The ndh genes encode the NAD(PH dehydrogenase complex, believed essential in terrestrial environments, where it increases photosynthetic efficiency in variable light intensities. The modified structure of the N. flexilis plastid genome suggests that adaptation to submersed environments, where light is scarce, has involved the loss of the NDH complex in at least some photosynthetic angiosperms.

  7. High performance quantum cascade lasers: Loss, beam stability, and gain engineering

    Science.gov (United States)

    Bouzi, Pierre Michel

    Quantum Cascade (QC) lasers are semiconductor devices emitting in the mid-infrared (3-30 micron) and terahertz (30-300 micron) regions of the electromagnetic spectrum. Since their first demonstration by Jerome Faist et. al. in 1994, they have evolved very quickly into high performance devices and given rise to many applications such as trace-gas sensing, medical diagnosis, free-space communication, and light detection and ranging (LIDAR). In this thesis, we investigate a further increase of the performance of QC devices and, through meticulous device modeling and characterizations, gain a deeper understanding of several of their unique characteristics, especially their carrier transport and lifetime, their characteristic temperature, their waveguide loss and modal gain, their leakage current, and their transverse mode profile. First, in our quest to achieve higher performance, we investigate the effect of growth asymmetries on device transport characteristics. This investigation stems from recent studies on the role of interface roughness on intersubband scattering and device performance. Through a symmetric active core design, we find that interface roughness and ionized impurity scattering induced by dopant migration play a significant role in carrier transport through the device. Understanding how interface roughness affects intersubband scattering, in turn, we engineer the gain in QC devices by placing monolayer barriers at specific locations within the device band structure. These strategically placed additional thin barrier layers introduce roughness scattering into the device active region, thereby selectively decreasing the lower laser state lifetime and increasing population inversion necessary for laser action. Preliminary measurement results from modified devices reveal a 50% decrease in the emission broadening compared to the control structures, which should lead to a two-fold increase in gain. A special class of so-called "strong coupling" QC lasers

  8. High temperature ultrasonic sensor for fission gas characterization in MTR harsh environment

    Science.gov (United States)

    Gatsa, O.; Combette, P.; Rozenkrantz, E.; Fourmentel, D.; Destouches, C.; Ferrandis, J. Y. AD(; )

    2018-01-01

    In the contemporary world, the measurements in hostile environment is one of the predominant necessity for automotive, aerospace, metallurgy and nuclear plant. The measurement of different parameters in experimental reactors is an important point in nuclear power strategy. In the near past, IES (Institut d'Électronique et des Systèmes) on collaboration with CEA (Commissariat à l'Energie Atomique et aux Energies Alternatives) have developed the first ultrasonic sensor for the application of gas quantity determination that has been tested in a Materials Testing Reactor (MTR). Modern requirements state to labor with the materials that possess stability on its parameters around 350°C in operation temperature. Previous work on PZT components elaboration by screen printing method established the new basis in thick film fabrication and characterization in our laboratory. Our trials on Bismuth Titanate ceramics showed the difficulties related to high electrical conductivity of fabricated samples that postponed further research on this material. Among piezoceramics, the requirements on finding an alternative solution on ceramics that might be easily polarized and fabricated by screen printing approach were resolved by the fabrication of thick film from Sodium Bismuth Titanate (NBT) piezoelectric powder. This material exhibits high Curie temperature, relatively good piezoelectric and coupling coefficients, and it stands to be a good solution for the anticipated application. In this paper, we present NBT thick film fabrication by screen printing, characterization of piezoelectric, dielectric properties and material parameters studies in dependence of temperature. Relatively high resistivity in the range of 1.1013 Ohm.cm for fabricated thick film is explained by Aurivillius structure in which a-and b-layers form perovskite structure between oxides of c-layer. Main results of this study are presented and discussed in terms of feasibility for an application to a new sensor

  9. Evaluation of dry feeding and liquid feeding to lactating sows under high temperature environment

    Directory of Open Access Journals (Sweden)

    J. S. Hong

    2016-10-01

    Full Text Available Abstract Background Liquid feeding system has been introduced to domestic swine farms, but negative cognition about liquid feeding system has been remained for feed waste decay related with poor management and microbial contamination. For these reasons, this study was conducted to evaluate the effects of feeding method in lactating sows. Methods A total of 30 mixed-parity (average 4.13 lactating sows (Yorkshire × Landrace with an initial BW of 218.8 ± 19.5kg was used in a 3 week trial. Sows were allotted to 1 of 2 treatments in a completely randomized design by their body weight, backfat thickness, parity and alive litter weight. One of treatments was dry feeding and the other was liquid feeding (water to feed ratio, 1:1. Experimental diets contained 3265 kcal ME/kg, 12.6 % CP, 5.76 % EE, 1.09 % total lysine, 0.25 % total methionine, as fed basis. Results Dry feeding treatment had high body weight loss rather than liquid feeding treatment (P = 0.04. Dry feeding treatment had tendency to increase litter weight at 21d of lactation (P = 0.06 and litter weight gain (P = 0.04 during lactation period (0–3 week. Sows fed dry feeding method made milk containing high content of casein and total solid rather than sows fed liquid feeding method (P = 0.04. In addition, dry feeding treatment had tendency to higher content of milk fat, protein and solid not fat on 21d of lactation (P = 0.07. Sows fed dry feeding type also showed higher milk energy content in milk of 21d lactation (P = 0.05. Furthermore, liquid feeding treatment showed high occurrence in feed waste during lactation period (P < 0.01. Conclusion Dry feeding method was more suitable feeding method to lactating sows under high temperature environment like lactating barn.

  10. Low-loss high-confinement waveguides and microring resonators in AlGaAs-on-insulator

    DEFF Research Database (Denmark)

    Ottaviano, Luisa; Pu, Minhao; Semenova, Elizaveta

    2016-01-01

    microring resonators. Here, we report a process tomake high-quality AlGaAs-on-insulator (AlGaAsOI) waferswhere high confinement waveguides can be realized. Using optimized patterning processes, we fabricated AlGaAsOI waveguides with propagation losses as low as 1 dB/cmand microring resonators with quality......AlGaAs is a promising material for integrated nonlinearphotonics due to its intrinsic high nonlinearity. However,the challenging fabrication of deep etched AlGaAs devices makes it difficult to realize high-performance devices such as low-loss dispersion engineered waveguides and high quality...... factors up to 350,000 at telecom wavelengths. Our demonstration opens new prospects for AlGaAs devices in integrated nonlinear photonics....

  11. Habitual physical activity and plasma metabolomic patterns distinguish individuals with low vs. high weight loss during controlled energy restriction.

    Science.gov (United States)

    Piccolo, Brian D; Keim, Nancy L; Fiehn, Oliver; Adams, Sean H; Van Loan, Marta D; Newman, John W

    2015-04-01

    Total weight loss induced by energy restriction is highly variable even under tightly controlled conditions. Identifying weight-loss discriminants would provide a valuable weight management tool and insights into body weight regulation. This study characterized responsiveness to energy restriction in adults from variables including the plasma metabolome, endocrine and inflammatory markers, clinical indices, body composition, diet, and physical activity. Data were derived from a controlled feeding trial investigating the effect of 3-4 dairy product servings in an energy-restricted diet (2092 kJ/d reduction) over 12 wk. Partial least squares regression was used to identify weight-loss discriminants in 67 overweight and obese adults. Linear mixed models were developed to identify discriminant variable differences in high- vs. low-weight-loss responders. Both pre- and postintervention variables (n = 127) were identified as weight-loss discriminants (root mean squared error of prediction = 1.85 kg; Q(2) = 0.43). Compared with low-responders (LR), high-responders (HR) had greater decreases in body weight (LR: 2.7 ± 1.6 kg; HR: 9.4 ± 1.8 kg, P physical activity (LR: 127 ± 52 min; HR: 167 ± 68 min, P = 0.02), sedentary activity (LR: 1090 ± 99 min; HR: 1017 ± 110 min, P = 0.02), and plasma stearate [LR: 102,000 ± 21,000 quantifier ion peak height (QIPH); HR: 116,000 ± 24,000 QIPH, P = 0.01]. Overweight and obese individuals highly responsive to energy restriction had accelerated reductions in adiposity, likely supported in part by higher lipid mobilization and combustion. A novel observation was that person-to-person differences in habitual physical activity and magnitude of weight loss were accompanied by unique blood metabolite signatures. This trial was registered at clinicaltrials.gov as NCT00858312. © 2015 American Society for Nutrition.

  12. Impacts of management alternatives on rice yield and nitrogen losses to the environment: A case study in rural Sri Lanka.

    Science.gov (United States)

    Stone, Elizabeth C; Hornberger, George M

    2016-01-15

    Maintaining crop yields is vital as populations increase, but environmental degradation resulting from cultivation must be prevented. In particular, freshwater resources are at risk of nitrate leaching from superfluous fertilization. This research explores the tradeoffs between maximizing yield and limiting environmental impacts of rice production in Sri Lanka. The DeNitrification-DeComposition (DNDC) model was used to examine how various combinations of fertilization and irrigation management affect yield, nitrous oxide (N2O) emissions, and nitrogen (N) leaching in paddy systems under climate and soil conditions in the dry zone of Sri Lanka from 1991 to 2010. Simulated fertilizer application rates ranged from zero to 2700 kgN/ha and simulated irrigation schemes were continuously flooded, marginally flooded, and rain-fed. Increasing fertilizer levels from zero to 300 kgN/ha per year increased yield but application of fertilizer beyond that amount ceased to affect yield for any of the three irrigation schemes. The combination of management options for obtaining the maximum grain yield, near 9000 kgC/ha, with the greatest amount of N uptake and relatively low nitrate leaching was using 225 kgN/ha under a continuously flooded regime. This research explores how cultivation in rice-growing regions in south Asia affects the environment and the N cycle, and demonstrates how informed management of these systems can reduce external inputs of N fertilizer without impacting yield. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Practice of AC loss measurement in high Tc superconductor; Koon chodendo senzai no koryu sonshitsu sokutei jisshu

    Energy Technology Data Exchange (ETDEWEB)

    Amemiya, N.; Tsukamoto, O.; Ciszek, M. [Yokohama National Univ., Yokohama (Japan). Faculty of Engineering

    1999-06-07

    The cooperative research promotion center in the Yokohama National University was set up for a purpose to promote the co-operative research with civilian agencies, conduct and the co-operate technical education to engineers from civilian agencies and take the technical discussion and supply the academic information with civilian agencies. As one part of this work, the engineer training called as the high technology training was conducted. In this paper, the seminar on the alternate current loss measurement conducted in November 1998 was reported. This training was a 'high' technology training for an objective of engineers, 8 participants included engineers and graduate students in a major of superconductivity from makers, civilian institutes and universities as the superconducting specialists attended this lecture. In this training, lectures on the loss generating mechanism and the loss measurement principle and its practical use, manufacture of the measuring samples, measurement (the energization loss and magnetization loss), the report of measured results and examination and comments were carried out in order. In the manufacture of samples, participants carried out all soldering and pick-up coil rolls by handling sample tapes and sample holder parts. (NEDO)

  14. PD-Detection vs. Loss Measurements at High Voltages with variable frequencies

    DEFF Research Database (Denmark)

    Holbøll, Joachim T.; Edin, Hans

    1999-01-01

    Partial discharge-activity (PD) in internal voids in epoxy plastic was measured at AC voltages from below inception to 3 times inception with variable frequencies in the range 0.1 to 100Hz.The results from phase/height analyses were compared to dielec-tric loss measurements and related to the app......Partial discharge-activity (PD) in internal voids in epoxy plastic was measured at AC voltages from below inception to 3 times inception with variable frequencies in the range 0.1 to 100Hz.The results from phase/height analyses were compared to dielec-tric loss measurements and related...

  15. Weight loss in obese men by caloric restriction and high-dose diazoxide-mediated insulin suppression.

    NARCIS (Netherlands)

    Boekel, G.A.J van; Loves, S.; Sorge, A van; Ruinemans-Koerts, J.; Rijnders, T.; Boer, H. de

    2008-01-01

    OBJECTIVE: To examine the concept whether high-dose diazoxide (DZX)-mediated insulin suppression, in combination with moderate caloric restriction and increased physical activity, can establish a weight loss of at least 15% in obese hyperinsulinaemic men. DESIGN: Open, uncontrolled, 6-month pilot

  16. MTOR signaling and ubiquitin-proteosome gene expression in the preservation of fat free mass following high protein, calorie restricted weight loss

    OpenAIRE

    McIver Cassandra M; Wycherley Thomas P; Clifton Peter M

    2012-01-01

    Abstract Caloric restriction is one of the most efficient ways to promote weight loss and is known to activate protective metabolic pathways. Frequently reported with weight loss is the undesirable consequence of fat free (lean muscle) mass loss. Weight loss diets with increased dietary protein intake are popular and may provide additional benefits through preservation of fat free mass compared to a standard protein, high carbohydrate diet. However, the precise mechanism by which a high prote...

  17. Break‐down of Losses in High Performing Metal‐Supported Solid Oxide Fuel Cells

    DEFF Research Database (Denmark)

    Kromp, A.; Nielsen, Jimmi; Blennow Tullmar, Peter

    2013-01-01

    A detailed electrochemical impedance study with the help of the distribution of relaxation times (DRT) method and a subsequent CNLS‐fit enabled us to quantitatively analyze the different loss contributions in the cell: the ohmic resistance and the polarization processes related to the gas diffusion...

  18. Design of low-loss and highly birefringent hollow-core photonic crystal fiber

    DEFF Research Database (Denmark)

    Roberts, Peter John; Williams, D.P.; Sabert, H.

    2006-01-01

    A practical hollow-core photonic crystal fiber design suitable for attaining low-loss propagation is analyzed. The geometry involves a number of localized elliptical features positioned on the glass ring that surrounds the air core and separates the core and cladding regions. The size of each fea...

  19. A rare case of recurrent pregnancy loss associated with high-titer positivity for perinuclear anti-neutrophilic cytoplasmic antibodies

    Directory of Open Access Journals (Sweden)

    Akhila Vasudeva

    2012-01-01

    Full Text Available We present a case of recurrent pregnancy loss associated with unusual constellation of utoimmunity-related features such as hypertension, severe hrombocytopenia, hypothyroidism and persistent high titers of perinuclear antineutrophilic cytoplasmic antibodies. Her clinical features did not fit into a particular diagnosis of vasculitides, systemic lupus erythematosis (SLE or other known autoimmune diseases where this autoantibody is found in high titers. We report the unusual association of this autoantibody with recurrent early fetal demise in this case.

  20. Eco-engineered rock pools: a concrete solution to biodiversity loss and urban sprawl in the marine environment

    Science.gov (United States)

    Firth, Louise B.; Browne, Keith A.; Knights, Antony M.; Hawkins, Stephen J.; Nash, Róisín

    2016-09-01

    In coastal habitats artificial structures typically support lower biodiversity and can support greater numbers of non-native and opportunistic species than natural rocky reefs. Eco-engineering experiments are typically trialed to succeed; but arguably as much is learnt from failure than from success. Our goal was to trial a generic, cost effective, eco-engineering technique that could be incorporated into rock armouring anywhere in the world. Artificial rock pools were created from manipulated concrete between boulders on the exposed and sheltered sides of a causeway. Experimental treatments were installed in locations where they were expected to fail and compared to controls installed in locations in which they were expected to succeed. Control pools were created lower on the structure where they were immersed on every tidal cycle; experimental pools were created above mean high water spring tide which were only immersed on spring tides. We hypothesised that lower and exposed pools would support significantly higher taxon and functional diversity than upper and sheltered pools. The concrete pools survived the severe winter storms of 2013/14. After 12 months, non-destructive sampling revealed significantly higher mean taxon and functional richness in lower pools than upper pools on the exposed side only. After 24 months the sheltered pools had become inundated with sediments, thus failing to function as rock pools as intended. Destructive sampling on the exposed side revealed significantly higher mean functional richness in lower than upper pools. However, a surprisingly high number of taxa colonised the upper pools leading to no significant difference in mean taxon richness among shore heights. A high number of rare taxa in the lower pools led to total taxon richness being almost twice that of upper pools. These findings highlight that even when expected to fail concrete pools supported diverse assemblages, thus representing an affordable, replicable means of

  1. Preferred low- and high-frequency compression ratios among hearing aid users with moderately severe to profound hearing loss.

    Science.gov (United States)

    Keidser, Gitte; Dillon, Harvey; Dyrlund, Ole; Carter, Lyndal; Hartley, David

    2007-01-01

    This study aimed to determine the low- and high-frequency compression ratios of a fast-acting device that were preferred by people with moderately severe to profound hearing loss. Three compression ratios (1:1, 1.8:1, and 3:1) were combined in the low and high frequencies to produce nine schemes that were evaluated pair-wise for three weeks in the field using an adaptive procedure. The evaluation was performed by 21 experienced hearing aid users with a moderately severe to profound hearing loss. Diaries and an exit interview were used to monitor preferences. Generally, the subjects preferred lower compression ratios than are typically prescribed, especially in the low frequencies. Specifically, 11 subjects preferred linear amplification in the low frequencies, and 14 subjects preferred more compression in the high than in the low frequencies. Preferences could not be predicted from audiometric data, onset of loss, or past experience with amplification. The data suggest that clients with moderately severe to profound hearing loss should be fitted with low-frequency compression ratios in the range 1:1 to 2:1 and that fine-tuning is essential.

  2. High-protein diet promotes a moderate postpartum weight loss in a prospective cohort of Brazilian women.

    Science.gov (United States)

    de Castro, Maria Beatriz T; Kac, Gilberto; de Leon, Antonio P; Sichieri, Rosely

    2009-01-01

    Whether a high-protein (HP) diet promotes body weight loss (BWL) when compared with a low-protein (LP) diet is still unclear. Therefore, we evaluated the effects of an HP diet on BWL during postpartum. A food-frequency questionnaire with 81 items was applied at 6 mo after delivery to evaluate the diet of 430 postpartum women aged 18-45 y. Body weight was measured approximately at 0.5, 2, 6, and 9 mo after delivery. Body weight loss was modeled by comparing an HP diet (> or =1.2g . kg(-1) . d(-1)) with an LP diet (women in the HP group lost 316+/-0.062g of body weight more per month (Pweight loss. Further studies should evaluate the long-term consequences of an HP diet postpartum.

  3. High honey bee losses in the winter of 2016-2017 in Timiș county, Romania

    Directory of Open Access Journals (Sweden)

    Daniela Marina Mot

    2017-05-01

    Full Text Available Beginning with November 2016 beekeepers from Timiș county reported bee colonies losses. During the winter months the situation became more the situation has become more severe, increasing losses of bee families. From November 2016, untill February 2017 were been received samples of dead bees from 23 different apiaries in Timiș county. The dead honey bees were analized in the way to discover what kind of causes produced all these losses. Was also proceeded to analyze the bacterial flora from bees intestine. Bacteriological examination of bees intestine and the cultivation on special medium of culture emphasized rich cultures of Paenibacillus larvae subsp. larvae (Bacillus larvae, etiologic agent for American foulbrood. These bacteria were been isolated from bee intestine in samples provided from 18 apiaries (78.26%. There are many causes of high degree of bee mortality in winter 2016-2017 but the isolation of Paenibacillus larvae subsp. larvae maybe was one of them.

  4. Effect of Curing Temperature on the Durability of Concrete under Highly Geothermal Environment

    Directory of Open Access Journals (Sweden)

    Yang Tang

    2017-01-01

    Full Text Available To determine the durability of concrete in the actual temperature and humidity of the tunnel environment, this study investigates the mechanical properties, permeability of chloride ion, relative dynamic elastic modulus, and mass loss ratio of concrete specimens cured in the temperature which varied from normal, 40, 60, 75, and 90°C, and the humidity was kept at 90% continuously. Experimental results reveal that the hot temperature curing environment may benefit early stage strength development but reduce the long-term strength. It is proved that 60°C is a critical point. At above 60°C, the strength of the concrete material and its resistance to chloride ion permeability showed a decreasing trend; however, in the appropriate temperature range, the frost resistance properties of the concrete are improved with increasing temperature.

  5. Effects of autoionization in electron loss from heliumlike highly charged ions in fast collisions with atomic particles

    Science.gov (United States)

    Lyashchenko, K. N.; Andreev, O. Yu.; Voitkiv, A. B.

    2017-11-01

    We study theoretically single-electron loss from the ground state of a heliumlike highly charged ion in fast collisions with an atomic particle (a nucleus or an atom), focusing on electron emission energies where the so-called excitation-autoionization channel of electron loss becomes of importance. The presence of this channel leads to the appearance of sharp structures in the energy distribution of the emitted electrons and may also noticeably influence the angular distributions of the emission in the vicinity of autoionization resonances. We performed calculations for electron loss from Ca18 +(1 s2) and Zn28 +(1 s2) in 100 MeV/u collisions with neon. It is shown that two qualitatively different subchannels (which involve either one or two interactions between the electrons of the ion and the incident atomic particle) substantially contribute to excitation-autoionization and take active part in the interference with the direct channel of electron loss; however, they practically do not interfere with each other. Our consideration also shows that the account of QED corrections is important for an accurate description of electron loss even from relatively light heliumlike HCIs.

  6. High and Low Responders in a Comprehensive Lifestyle Program for Weight Loss - Secondary Analysis of a Randomized Controlled Trial.

    Science.gov (United States)

    Melchart, Dieter; Wühr, Erich; Weidenhammer, Wolfgang

    2017-01-01

    Unhealthy lifestyle is often related to overweight and obesity and thus to chronic diseases. Web-based programs might be an option for a comprehensive approach to improving long-term weight management. Data from a randomized controlled trial (RCT) evaluating the impact of a lifestyle program on weight reduction were used for a secondary analysis. The objectives were (a) to identify potential predictors for marked weight loss, (b) to explore associations of weight reduction with changes in health-related variables, and (c) to evaluate whether self-monitoring of the daily lifestyle is associated with weight loss. 67 subjects with a body mass index of 28-35 who underwent the 1-year 'Individual Health Management' (IHM) program were included in the analysis (mean age 49.8 years, 79% female). Two subgroups (high response: ≥7.5% weight reduction vs. low response: weight loss. 70% of the subjects fulfilled the criterion of high response. There were no statistically significant differences between the two subgroups with respect to sociodemographic and baseline data. Regression analysis failed to identify any predictors for the amount of weight reduction. Subjects with high response showed a more distinct improvement in life satisfaction and neurovegetative stability. The findings indicated an association between the level of self-monitoring and weight loss. More research is needed to establish optimal strategies for maximizing the longer-term maintenance of weight loss and prevention effects. For weight reduction, support strategies like feedback learning through self-monitoring, reporting systems, and self-performance measurement with questionnaires might ameliorate high-intensity lifestyle modification programs. © 2017 S. Karger GmbH, Freiburg.

  7. Nuclear and Non-Ionizing Energy-loss of Electrons with Low and Relativistic Energies in Materials and Space Environment

    CERN Document Server

    Boschini, M.J.

    2012-01-01

    The treatment of the electron-nucleus interaction based on the Mott differential cross section was extended to account for effects due to screened Coulomb potentials, finite sizes and finite rest masses of nuclei for electrons above 200 keV and up to ultra high energies. This treatment allows one to determine both the total and differential cross sections, thus, subsequently to calculate the resulting nuclear and non-ionizing stopping powers. Above a few hundreds of MeV, neglecting the effect due to finite rest masses of recoil nuclei the stopping power and NIEL result to be largely underestimated; while, above a few tens of MeV the finite size of the nuclear target prevents a further large increase of stopping powers which approach almost constant values.

  8. Aerodynamic design and optimization of high altitude environment simulation system based on CFD

    Science.gov (United States)

    Ma, Pingchang; Yan, Lutao; Li, Hong

    2017-05-01

    High altitude environment simulation system (HAES) is built to provide a true flight environment for subsonic vehicles, with low density, high speed, and short time characteristics. Normally, wind tunnel experiments are based on similar principal, such as parameters of Re or Ma, in order to shorten test product size. However, the test products in HAES are trim size, so more attention is put on the true flight environment simulation. It includes real flight environment pressure, destiny and real flight velocity, and its type velocity is Ma=0.8. In this paper, the aerodynamic design of HAES is introduced and its rationality is explained according to CFD calculation based on Fluent. Besides, the initial pressure of vacuum tank in HAES is optimized, which is not only to meet the economic requirements, but also to decrease the effect of additional stress on the test product in the process of the establishment of the target flow field.

  9. The Behavior Of Asymmetric Frontal Couplings With Permanent Magnets In Magnetic Powder And High Temperature Environments

    Directory of Open Access Journals (Sweden)

    Ion DOBROTA

    2002-12-01

    Full Text Available The main purpose of this paper is the comparative analysis of the behavior of frontal couplings with Nd-Fe-B permanent magnets in difficult environments, specific to metallurgy – such as environments with magnetic powders and high temperature – in two constructive variants: symmetric couplings and asymmetric couplings (with divided poles. The results show the superior performance of asymmetric couplings under the given conditions

  10. Challenges and Opportunities for Security in High-Performance Computing Environments

    OpenAIRE

    Peisert, S

    2017-01-01

    High-performance computing (HPC) environments have numerous distinctive elements that make securing them different than securing traditional computing systems. In some cases this is due to the way that HPC systems are implemented. In other cases, it is due to the way that HPC systems are used, or a combination of both issues. In this article, we discuss these distinctions and also discuss which security procedures and mechanisms are and are not appropriate in HPC environments, and where gaps ...

  11. Low-loss design for the high-intensity accumulator ring of the Spallation Neutron Source

    Directory of Open Access Journals (Sweden)

    J. Wei

    2000-08-01

    Full Text Available This paper summarizes the low-loss design for the Spallation Neutron Source accumulator ring [“Spallation Neutron Source Design Manual” (unpublished]. A hybrid lattice consisting of FODO arcs and doublet straights provides optimum matching and flexibility for injection and collimation. For this lattice, optimization focuses on six design goals: a space-charge tune shift low enough (below 0.15 to avoid strong resonances, adequate transverse and momentum acceptance for efficient beam collimation, injection optimized for desired target beam shape and minimal halo development, compensation of magnet field errors, control of impedance and instability, and prevention against accidental system malfunction. With an expected collimation efficiency of more than 90%, the uncontrolled fractional beam loss is expected to be at the 10^{-4} level.

  12. AC losses of high temperature superconducting wires in combined condition of transverse magnetic field and transport current; Ojikai{center_dot}denryu no doji soinji ni okeru koon chodendo senzai no koryu sonshitsu

    Energy Technology Data Exchange (ETDEWEB)

    Kajikawa, K.; Takenaka, A.; Kawasaki, K.; Iwakuma, M.; Funaki, K. [Kyushu Univ., Fukuoka (Japan)

    2000-05-29

    We propose the summary measuring method as a method for conveniently evaluating ac loss under various electromagnetic environment of superconducting wire rod high precise. It has evaluated the ac loss as simultaneously; it has applied current and magnetic field until now to Bi-2223 silver sheath wire rod using this technique experimentally. And, got measurement result agreed with the numerical calculation result well, and it was able to verify the usefulness of this technique. However, the condition of the simultaneous sweep examined until now is only the case in which current and magnetic field are in-phases, and it is necessary to examine whether it is also estimable on the ac loss in both in case of phase difference by summary measuring method. This time, the ac loss as simultaneously, it applied precedence, current with phase difference in oxide superconducting wire rod and magnetic field to the experimental examination was estimated by numerical calculation. (NEDO)

  13. Quantum-Relay-Assisted Key Distribution over High Photon Loss Channels

    OpenAIRE

    Zhang, An-Ning; Chen, Yu-Ao; Lu, Chao-Yang; Zhou, Xiao-Qi; Zhao, Zhi; ZHANG, QIANG; Yang, Tao; Pan, Jian-Wei

    2005-01-01

    The maximum distance of quantum communication is limited due to the photon loss and detector noise. Exploiting entanglement swapping, quantum relay could offer ways to extend the achievable distance by increasing the signal to noise ratio. In this letter we present an experimental simulation of long distance quantum communication, in which the superiority of quantum relay is demonstrated. Assisted by quantum relay, we greatly extend the distance limit of unconditional secure quantum communica...

  14. Experimental evidence of a nonlinear loss mechanism in highly doped Yb:LuAG crystal.

    Science.gov (United States)

    Pirri, Angela; Toci, Guido; Nikl, Martin; Babin, Vladimir; Vannini, Matteo

    2014-02-24

    We report a rigorous study of the spectroscopic, laser and thermal properties of a 10at.% and a 15at.% Yb:LuAG crystals. A loss mechanism is observed in the medium with the highest doping, pumped at 936 nm and 968 nm, as a sharp and dramatic decrease of the laser output power is measured at higher excitation densities. The nonlinearity of the loss mechanism is confirmed by the fluorescence data and by the thermal lens. In particular, the dioptric power of the thermal lens acquired at different pumping levels shows a strong deviation of the expected linear trend. Here we report the influence of both the concentration and the ion excitation density of Yb3+ on the output powers, the slope efficiencies and the thresholds. Conversely excellent results are achieved with the 10at.%, which does not show any loss mechanism as at 1046 nm it delivers 11.8 W with a slope efficiency of η(s) = 82%, which is, to the best of our knowledge, the highest value reported in literature for this material.

  15. Energy loss of a high charge bunched electron beam in plasma: Simulations, scaling, and accelerating wakefields

    Directory of Open Access Journals (Sweden)

    J. B. Rosenzweig

    2004-06-01

    Full Text Available The energy loss and gain of a beam in the nonlinear, “blowout” regime of the plasma wakefield accelerator, which features ultrahigh accelerating fields, linear transverse focusing forces, and nonlinear plasma motion, has been asserted, through previous observations in simulations, to scale linearly with beam charge. Additionally, from a recent analysis by Barov et al., it has been concluded that for an infinitesimally short beam, the energy loss is indeed predicted to scale linearly with beam charge for arbitrarily large beam charge. This scaling is predicted to hold despite the onset of a relativistic, nonlinear response by the plasma, when the number of beam particles occupying a cubic plasma skin depth exceeds that of plasma electrons within the same volume. This paper is intended to explore the deviations from linear energy loss using 2D particle-in-cell simulations that arise in the case of experimentally relevant finite length beams. The peak accelerating field in the plasma wave excited behind the finite-length beam is also examined, with the artifact of wave spiking adding to the apparent persistence of linear scaling of the peak field amplitude into the nonlinear regime. At large enough normalized charge, the linear scaling of both decelerating and accelerating fields collapses, with serious consequences for plasma wave excitation efficiency. Using the results of parametric particle-in-cell studies, the implications of these results for observing severe deviations from linear scaling in present and planned experiments are discussed.

  16. High humidity leads to loss of infectious influenza virus from simulated coughs.

    Directory of Open Access Journals (Sweden)

    John D Noti

    Full Text Available BACKGROUND: The role of relative humidity in the aerosol transmission of influenza was examined in a simulated examination room containing coughing and breathing manikins. METHODS: Nebulized influenza was coughed into the examination room and Bioaerosol samplers collected size-fractionated aerosols (4 µM aerodynamic diameters adjacent to the breathing manikin's mouth and also at other locations within the room. At constant temperature, the RH was varied from 7-73% and infectivity was assessed by the viral plaque assay. RESULTS: Total virus collected for 60 minutes retained 70.6-77.3% infectivity at relative humidity ≤23% but only 14.6-22.2% at relative humidity ≥43%. Analysis of the individual aerosol fractions showed a similar loss in infectivity among the fractions. Time interval analysis showed that most of the loss in infectivity within each aerosol fraction occurred 0-15 minutes after coughing. Thereafter, losses in infectivity continued up to 5 hours after coughing, however, the rate of decline at 45% relative humidity was not statistically different than that at 20% regardless of the aerosol fraction analyzed. CONCLUSION: At low relative humidity, influenza retains maximal infectivity and inactivation of the virus at higher relative humidity occurs rapidly after coughing. Although virus carried on aerosol particles 40% will significantly reduce the infectivity of aerosolized virus.

  17. 40 CFR 86.134-96 - Running loss test.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Running loss test. 86.134-96 Section... Heavy-Duty Vehicles; Test Procedures § 86.134-96 Running loss test. (a) Overview. Gasoline- and methanol-fueled vehicles are to be tested for running loss emissions during simulated high-temperature urban...

  18. 40 CFR 86.1234-96 - Running loss test.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 19 2010-07-01 2010-07-01 false Running loss test. 86.1234-96 Section... Methanol-Fueled Heavy-Duty Vehicles § 86.1234-96 Running loss test. (a) Overview. Gasoline- and methanol-fueled vehicles are to be tested for running loss emissions during simulated high-temperature urban...

  19. Development of an FPW Biosensor with Low Insertion Loss and High Fabrication Yield for Detection of Carcinoembryonic Antigen

    Science.gov (United States)

    Lan, Je-Wei; Huang, I-Yu; Lin, Yu-Cheng; Lin, Chang-Yu; Chen, Jian-Lin; Hsieh, Chia-Hsu

    2016-01-01

    In the last two decades, various flexural plate-wave (FPW)-based biosensors with low phase velocity, low operation frequency, high sensitivity, and short response time, have been developed. However, conventional FPW transducers have low fabrication yield because controlling the thickness of silicon/isolation/metal/piezoelectric multilayer floating thin-plate is difficult. Additionally, conventional FPW devices usually have high insertion loss because of wave energy dissipation to the silicon substrate or outside area of the output interdigital transducers (IDTs). These two disadvantages hinder the application of FPW devices. To reduce the high insertion loss of FPW devices, we designed two focus-type IDTs (fan-shaped and circular, respectively) that can effectively confine the launched wave energy, and adopted a focus-type silicon-grooved reflective grating structure (RGS) that can reduce the wave propagation loss. To accurately control the thickness of the silicon thin-plate and substantially improve the fabrication yield of FPW transducers, a 60 °C/27 °C two-step anisotropic wet etching process was developed. Compared with conventional FPW devices (with parallel-type IDTs and without RGS), the proposed FPW devices have lower insertion loss (36.04 dB) and higher fabrication yield (63.88%). Furthermore, by using cystamine-based self-assembled monolayer (SAM) nanotechnology, we used the improved FPW device to develop a novel FPW-based carcinoembryonic antigen (CEA) biosensor for detection of colorectal cancer, and this FPW-CEA biosensor has a low detection limit (5 ng/mL), short response time (<10 min), high sensitivity (60.16–70.06 cm2/g), and high sensing linearity (R-square = 0.859–0.980). PMID:27834798

  20. Failure modes of large surface avalanche photo diodes in high-energy physics environments

    Science.gov (United States)

    Anzivino, G.; Bai, J.; Bencheikh, B.; Contin, A.; DeSalvo, R.; Fagen, S.; He, H.; Liu, L.; Lundin, M.; Madden, R. M.; Mondardini, M. R.; Szawlowski, M.; Wang, K.; Xia, X.; Yang, C.; Zhao, M.

    1999-06-01

    Large area avalanche photo diodes (APD), a new and very promising type of light detector, were tested at high gain on a beam line and suddenly failed. A detailed study of the failure modes showed that these devices, if used at low gain and with special care, may actually be used in high-energy physics environments and indicates the road of development toward radiation hard, large area APDs. No problem was found when APDs are operated in absence of highly ionizing particles.

  1. Conductor of high electrical current at high temperature in oxygen and liquid metal environment

    Science.gov (United States)

    Powell, IV, Adam Clayton; Pati, Soobhankar; Derezinski, Stephen Joseph; Lau, Garrett; Pal, Uday B.; Guan, Xiaofei; Gopalan, Srikanth

    2016-01-12

    In one aspect, the present invention is directed to apparatuses for and methods of conducting electrical current in an oxygen and liquid metal environment. In another aspect, the invention relates to methods for production of metals from their oxides comprising providing a cathode in electrical contact with a molten electrolyte, providing a liquid metal anode separated from the cathode and the molten electrolyte by a solid oxygen ion conducting membrane, providing a current collector at the anode, and establishing a potential between the cathode and the anode.

  2. Low-beam-loss design of a compact, high-current deuteron radio frequency quadrupole accelerator

    Directory of Open Access Journals (Sweden)

    C. Zhang

    2004-10-01

    Full Text Available A 201.5 MHz, 50 mA, 2.0 MeV deuteron radio frequency quadrupole accelerator is proposed as the neutron generator for the neutron experiment facility project at Peking University, China. Based on better understanding of beam losses, some new optimization procedures concerning both longitudinal and transverse dynamics are adopted. Accordingly, the beam transmission efficiency is improved from 91.2% to 98.3% and the electrode length is shortened from 2.91 to 2.71 m. The fundamental physical analyses are performed to look inside the new design recipe and explain why it works.

  3. Silicon-free, low-loss and high contrast polymer multimode waveguides

    Science.gov (United States)

    Abdul-Hadi, Jalal; Gauthier, Marc Andre; Packirisamy, Muthukumaran

    2017-10-01

    The fabrication and characterization of SU-8 multimode optical waveguides on fused quartz and silicon oxide substrates were successfully realized and analyzed. Optical losses for the transverse electric (TE) mode polarization of 0.58 dB cm-1 and 1.44 dB cm-1 and transverse magnetic (TM) mode polarization of 0.73 dB cm-1 and 1.16 dB cm-1 were measured for SU-8 waveguides on fused quartz and silicon oxide substrates, respectively. The fabrication process for SU-8 waveguides on quartz developed herein could be applied for SU-8 optical integrated devices on other substrate materials.

  4. The role of learning environment on high school chemistry students' motivation and self-regulatory processes

    Science.gov (United States)

    Judd, Jeffrey S.

    Changes to the global workforce and technological advancements require graduating high school students to be more autonomous, self-directed, and critical in their thinking. To reflect societal changes, current educational reform has focused on developing more problem-based, collaborative, and student-centered classrooms to promote effective self-regulatory learning strategies, with the goal of helping students adapt to future learning situations and become life-long learners. This study identifies key features that may characterize these "powerful learning environments", which I term "high self-regulating learning environments" for ease of discussion, and examine the environment's role on students' motivation and self-regulatory processes. Using direct observation, surveys, and formal and informal interviews, I identified perceptions, motivations, and self-regulatory strategies of 67 students in my high school chemistry classes as they completed academic tasks in both high and low self-regulating learning environments. With social cognitive theory as a theoretical framework, I then examined how students' beliefs and processes changed after they moved from low to a high self-regulating learning environment. Analyses revealed that key features such as task meaning, utility, complexity, and control appeared to play a role in promoting positive changes in students' motivation and self-regulation. As embedded cases, I also included four students identified as high self-regulating, and four students identified as low self-regulating to examine whether the key features of high and low self-regulating learning environments played a similar role in both groups. Analysis of findings indicates that key features did play a significant role in promoting positive changes in both groups, with high self-regulating students' motivation and self-regulatory strategies generally remaining higher than the low self-regulating students; this was the case in both environments. Findings

  5. A High Performance Optical Disc Drive Unit For Use In Non-Benevolent Environments

    Science.gov (United States)

    Earman, A. M.

    1983-11-01

    Optical Disc Mass Storage Systems provide for storage of large quantities of digital data on a relatively compact medium with negligible access delays. Until now, however, all Optical Disc Systems have been designed for laboratory or computer room environments. For many years, RCA has been a leader in production of compact, rugged magnetic recording equipment for use in tactical and other non-benevolent environments. Now, this technology is being applied to Optical Disc Systems and the result is a design of a compact, high-data-rate, high-capacity data recording system for field operation. Discussion topics include system architecture and physical configuration.

  6. Track and vertex reconstruction of the ATLAS Inner Detector in the high multiplicity LHC environment

    CERN Document Server

    Wasicki, C; The ATLAS collaboration

    2012-01-01

    With an average number of up to 30 pile-up interactions per bunch crossing in 2012 data, the ATLAS Inner Detector at the LHC is performing in an environment beyond its design specifications. This has a significant impact on event reconstruction such as additional demands on CPU time and disk space as well as an increased probability to reconstruct fake tracks. Therefore the track and vertex reconstruction performance has been optimised in several high pile-up scenarios. Studies in data and simulation are presented which demonstrate that the performance of the Inner Detector track and vertex reconstruction is robust even in a high pile-up environment.

  7. Track and vertex reconstruction of the ATLAS Inner Detector in the high multiplicity LHC environment

    Science.gov (United States)

    Wasicki, Christoph

    2012-12-01

    With an average number of up to 30 pile-up interactions per bunch crossing in 2012 data, the ATLAS Inner Detector at the LHC is performing in an environment beyond its design specifications. This has a significant impact on event reconstruction such as additional demands on CPU time and disk space as well as an increased probability to reconstruct fake tracks. Therefore the track and vertex reconstruction performance has been optimised in several high pile-up scenarios (see [1]). Studies in data and simulation are presented which demonstrate that the performance of the Inner Detector track and vertex reconstruction is robust even in a high pile-up environment.

  8. Effect of a high-protein diet on maintenance of blood pressure levels achieved after initial weight loss

    DEFF Research Database (Denmark)

    Engberink, M F; Geleijnse, J M; Bakker, S J L

    2015-01-01

    in 420 overweight adults from the Diet, Obesity and Genes study. After an 8-week weight-loss period (>8% BW), subjects (42±6 years) were randomized to either a high-protein diet (23-28 en% protein) or a lower-protein control diet (10-15 en% protein) for 26 weeks. BMI after weight loss was 30.3±4.3 kg m......(-2), BP was 118/73 mm Hg and 28 subjects (6.5%) used antihypertensive agents. Systolic BP during 26 weeks of weight maintenance dietary intervention increased in both treatment groups, but it was 2.2 mm Hg less (95% CI: -4.6 to 0.2 mm Hg, P=0.08) in the high-protein group than in the lower...

  9. Corrosion and Creep of Candidate Alloys in High Temperature Helium and Steam Environments for the NGNP

    Energy Technology Data Exchange (ETDEWEB)

    Was, Gary; Jones, J. W.

    2013-06-21

    This project aims to understand the processes by which candidate materials degrade in He and supercritical water/steam environments characteristic of the current NGNP design. We will focus on understanding the roles of temperature, and carbon and oxygen potential in the 750-850 degree C range on both uniform oxidation and selective internal oxidation along grain boundaries in alloys 617 and 800H in supercritical water in the temperature range 500-600 degree C; and examining the application of static and cyclic stresses in combination with impure He environments in the temperature rang 750-850 degree C; and examining the application of static and cyclic stresses in combination with impure He environments in the temperature range 750-850 degree C over a range of oxygen and carbon potentials in helium. Combined, these studies wil elucidate the potential high damage rate processes in environments and alloys relevant to the NGNP.

  10. Dietary Adherence and Satisfaction with a Bean-Based High-Fiber Weight Loss Diet: A Pilot Study

    OpenAIRE

    Patrick M. O'Neil; Susan Pechon; Robert J. Malcolm; Strickland, William D.; Laura M. Nance; Turner, Tonya F.

    2013-01-01

    Objective. Dietary fiber can reduce hunger and enhance satiety, but fiber intake during hypocaloric weight loss diets typically falls short of recommended levels. We examined the nutritional effects and acceptability of two high-fiber hypocaloric diets differing in sources of fiber: (a) beans or (b) fruits, vegetables, and whole grains. Methods. Subjects were 2 men, 18 women, mean age = 46.9, and mean BMI = 30.6. Subjects completed 3-day food diaries in each of the two baseline weeks. Subject...

  11. The effects of high electronic energy loss on the chemical modification of polyimide

    CERN Document Server

    SunYouMei; Jin Yun Fan; Liu Chang Long; LiuJie; Wang Zhi Guang; Zhang Qi; Zhu Zhi Yong

    2002-01-01

    In order to observe the role of electronic energy loss (dE/dX) sub e on chemical modification of polyimide (PI), the multi-layer stacks (corresponding to different dE/dX) were irradiated by different swift heavy ions (1.37 GeV Ar sup 4 sup 0 , 1.98 GeV Kr sup 8 sup 4 , 1.755 GeV Xe sup 1 sup 3 sup 6 and 2.636 GeV U sup 2 sup 3 sup 8) under vacuum and room temperature. The chemical changes of modified PI films were studied by Fourier transform infrared (FTIR) and ultraviolet/visible (UV/Vis) absorption spectroscopy. The degradation of PI was investigated in the fluence range from 1x10 sup 1 sup 0 to 5.5x10 sup 1 sup 2 ions/cm sup 2 and different electronic energy loss from 0.77 to 11.5 keV/nm. The FTIR results show the absorbance of the typical function group decrease exponentially as a function of fluence. The alkyne end group was found after irradiation and its formation radii were 5.6 and 5.9 nm corresponding to 8.8 and 11.5 keV/nm Xe irradiation respectively. UV/Vis analysis indicates the radiation induced...

  12. Factors influencing student perceptions of high-school science laboratory environments.

    Science.gov (United States)

    Luketic, Christine D; Dolan, Erin L

    2013-04-01

    Science laboratory learning has been lauded for decades for its role in fostering positive student attitudes about science and developing students' interest in science and ability to use equipment. An expanding body of research has demonstrated the significant influence of laboratory environment on student learning. Further research has demonstrated differences in student perceptions based on giftedness. To explore the relationship between giftedness and students' perceptions of their learning environment, we examined students' perceptions of their laboratory learning environment in biology courses, including courses designated for high-achieving versus regular-achieving students. In addition, to explore the relationship between students' perceptions and the extent of their experience with laboratory learning in a particular discipline, we examined students' perceptions of their laboratory learning environment in first-year biology courses versus elective biology courses that require first-year biology as a prerequisite. We found that students in high-achieving courses had a more favourable perception of all aspects of their learning environment when compared with students in regular courses. In addition, student perceptions of their laboratory appeared to be influenced by the extent of their experience in learning science. Perceptions were consistent amongst regular- and high-achieving students regardless of grade level. In addition, perceptions of students in first year and beyond were consistent regardless of grade level. These findings have critical applications in curriculum development as well as in the classroom. Teachers can use student perceptions of their learning environment to emphasize critical pedagogical approaches and modify other areas that enable enhancement of the science laboratory learning environment.

  13. Perceived neighborhood environment and physical activity among high school students from Curitiba, Brazil.

    Science.gov (United States)

    Lopes, Adalberto Aparecido dos Santos; Lanzoni, Alessandra Nunes; Hino, Adriano Akira Ferreira; Rodriguez-Añez, Ciro Romélio; Reis, Rodrigo Siqueira

    2014-12-01

    To analyze the association between perceived neighborhood environment and physical activity (PA) in high school students from Curitiba (PR), Brazil. A sample of 1,611 high school students from public schools was surveyed. The PA was assessed through questions, engaged for at least 20 minutes or 60 minutes. Perceptions on neighborhood environment were assessed through ten questions about neighborhood characteristics. Gender, age and number of cars in the household were self-reported and used as confounding variables. Absolute and relative frequencies were used in the sample, and associations were tested through adjusted logistic regressions for the confounding variables and stratified by gender (p perception of the environment was associated to PA practice among boys and girls in this sample. The results suggest that some environmental characteristics which make neighborhoods more attractive could be related to PA among adolescents.

  14. A New High Frequency Injection Method Based on Duty Cycle Shifting without Maximum Voltage Magnitude Loss

    DEFF Research Database (Denmark)

    Wang, Dong; Lu, Kaiyuan; Rasmussen, Peter Omand

    2015-01-01

    The conventional high frequency signal injection method is to superimpose a high frequency voltage signal to the commanded stator voltage before space vector modulation. Therefore, the magnitude of the voltage used for machine torque production is limited. In this paper, a new high frequency...

  15. Can Hypocaloric, High-Protein Nutrition Support Be Used in Complicated Bariatric Patients to Promote Weight Loss?

    Science.gov (United States)

    Beebe, Mara Lee; Crowley, Nina

    2015-08-01

    Bariatric surgery, an effective treatment for morbid obesity, may result in complications that require nutrition support. Common goals for nutrition support in post-bariatric surgery patients include nutrition repletion, avoiding overfeeding, preserving lean body mass, and promoting wound healing. It is often questioned if continued weight loss can be part of the nutrition goals and if weight loss is safe for patients who become critically ill following bariatric surgery. Recent clinical practice guidelines from both the American Society for Parenteral and Enteral Nutrition (A.S.P.E.N.) and Society of Critical Care Medicine (SCCM) have recommended the use of hypocaloric, high-protein nutrition support in both critically and non-critically ill obese patients. Hypocaloric feedings of 50%-70% of estimated energy requirements based on predictive equations or clinical guidelines for nutrition support of hospitalized adult patients with obesity. Two small studies in complicated post-bariatric surgery patients requiring nutrition support have shown that the strategy of hypocaloric, high-protein feedings can result in positive outcomes, including positive nitrogen balance, wound healing, weight loss, and successful transition to oral diets. Additional research, including large, randomized studies, is still needed to validate these findings. However, based on a review of available clinical practice guidelines, predictive equations, indirect calorimetry, case studies, and systematic reviews, hypocaloric, high-protein nutrition support appears to at least be equal to eucaloric feedings and may be a useful tool for clinicians to achieve continued weight loss in complicated bariatric surgery patients requiring nutrition support. © 2015 American Society for Parenteral and Enteral Nutrition.

  16. High N, dry: Experimental nitrogen deposition exacerbates native shrub loss and nonnative plant invasion during extreme drought.

    Science.gov (United States)

    Valliere, Justin M; Irvine, Irina C; Santiago, Louis; Allen, Edith B

    2017-10-01

    Hotter, longer, and more frequent global change-type drought events may profoundly impact terrestrial ecosystems by triggering widespread vegetation mortality. However, severe drought is only one component of global change, and ecological effects of drought may be compounded by other drivers, such as anthropogenic nitrogen (N) deposition and nonnative plant invasion. Elevated N deposition, for example, may reduce drought tolerance through increased plant productivity, thereby contributing to drought-induced mortality. High N availability also often favors invasive, nonnative plant species, and the loss of woody vegetation due to drought may create a window of opportunity for these invaders. We investigated the effects of multiple levels of simulated N deposition on a Mediterranean-type shrubland plant community in southern California from 2011 to 2016, a period coinciding with an extreme, multiyear drought in the region. We hypothesized that N addition would increase native shrub productivity, but that this would increase susceptibility to drought and result in increased shrub loss over time. We also predicted that N addition would favor nonnatives, especially annual grasses, leading to higher biomass and cover of these species. Consistent with these hypotheses, we found that high N availability increased native shrub canopy loss and mortality, likely due to the higher productivity and leaf area and reduced water-use efficiency we observed in shrubs subject to N addition. As native shrub cover declined, we also observed a concomitant increase in cover and biomass of nonnative annuals, particularly under high levels of experimental N deposition. Together, these results suggest that the impacts of extended drought on shrubland ecosystems may be more severe under elevated N deposition, potentially contributing to the widespread loss of native woody species and vegetation-type conversion. © 2017 John Wiley & Sons Ltd.

  17. HIGH TEMPERATURE RESONANCE LOSSES IN SILICON-DOPED YTTRIUM-IRON GARNET (YIG)

    DEFF Research Database (Denmark)

    Epstein, D. J.; Tocci, L.

    1967-01-01

    The ferrimagnetic resonance linewidth of silicon-doped YIG, measured as a function of temperature at 13.4 kMHz, is found to show a pronounced peak at 105°C. The anisotropic behavior of this peak is in good agreement with the four-level valence-exchange model proposed by Clogston. The model yields...... for the electron ordering energy a value 5 × 10-4 eV which agrees closely with the energy deduced from magnetic anneal studies. The activation energy for electron transfer (0.25 eV) is virtually identical with values reported in investigations of electrical conductivity and acoustic loss. ©1967 The American...

  18. Surface and bulk modified high capacity layered oxide cathodes with low irreversible capacity loss

    Science.gov (United States)

    Manthiram, Arumugam (Inventor); Wu, Yan (Inventor)

    2010-01-01

    The present invention includes compositions, surface and bulk modifications, and methods of making of (1-x)Li[Li.sub.1/3Mn.sub.2/3]O.sub.2.xLi[Mn.sub.0.5-yNi.sub.0.5-yCo.sub.2- y]O.sub.2 cathode materials having an O3 crystal structure with a x value between 0 and 1 and y value between 0 and 0.5, reducing the irreversible capacity loss in the first cycle by surface modification with oxides and bulk modification with cationic and anionic substitutions, and increasing the reversible capacity to close to the theoretical value of insertion/extraction of one lithium per transition metal ion (250-300 mAh/g).

  19. Depression and emotional stress is highly prevalent among women with recurrent pregnancy loss

    DEFF Research Database (Denmark)

    Kolte, A M; Olsen, Line Rørbæk; Mikkelsen, E M

    2015-01-01

    STUDY QUESTION: Is the prevalence of psychological stress and moderate/severe depression higher for women with recurrent pregnancy loss (RPL) than pregnancy planners trying to conceive naturally? SUMMARY ANSWER: Both psychological stress and major depression are significantly more common among...... women with RPL than in those trying to conceive naturally. WHAT IS KNOWN ALREADY: RPL has a significant emotional impact on couples, especially the woman. Previous studies have shown inconclusive results. STUDY DESIGN, SIZE, DURATION: In this cross-sectional study, we compared the prevalence of stress......, and Cohen's Perceived Stress Scale (PSS) was used to measure stress. Relevant demographic data were also retrieved. MAIN RESULTS AND THE ROLE OF CHANCE: Of the RPL patients, 26 (8.6%) had a score on the MDI corresponding to moderate/severe depression, as did 40 (2.2%) of the women in Soon Parents Study...

  20. Performance of high performance concrete (HPC) in low pH and sulfate environment.

    Science.gov (United States)

    2013-05-01

    The goal of this research is to determine the impact of low pH and sulfate environment on high-performance concrete (HPC) and if the current structural and materials specifications provide adequate protections for concrete structures to meet the 75-y...

  1. Negotiating Identity and Science Teaching in a High-Stakes Testing Environment: An Elementary Teacher's Perceptions

    Science.gov (United States)

    Upadhyay, Bhaskar

    2009-01-01

    This study draws upon a qualitative case study to investigate the impact of the high-stakes test environment on an elementary teacher's identities and the influence of identity maintenance on science teaching. Drawing from social identity theory, I argue that we can gain deep insight into how and why urban elementary science teachers engage in…

  2. A harsh environment wireless pressure sensing solution utilizing high temperature electronics.

    Science.gov (United States)

    Yang, Jie

    2013-02-27

    Pressure measurement under harsh environments, especially at high temperatures, is of great interest to many industries. The applicability of current pressure sensing technologies in extreme environments is limited by the embedded electronics which cannot survive beyond 300 °C ambient temperature as of today. In this paper, a pressure signal processing and wireless transmission module based on the cutting-edge Silicon Carbide (SiC) devices is designed and developed, for a commercial piezoresistive MEMS pressure sensor from Kulite Semiconductor Products, Inc. Equipped with this advanced high-temperature SiC electronics, not only the sensor head, but the entire pressure sensor suite is capable of operating at 450 °C. The addition of wireless functionality also makes the pressure sensor more flexible in harsh environments by eliminating the costly and fragile cable connections. The proposed approach was verified through prototype fabrication and high temperature bench testing from room temperature up to 450 °C. This novel high-temperature pressure sensing technology can be applied in real-time health monitoring of many systems involving harsh environments, such as military and commercial turbine engines.

  3. Lesbian, Gay, Bisexual and Transgender Students: Perceived Social Support in the High School Environment

    Science.gov (United States)

    Munoz-Plaza, Corrine; Quinn, Sandra Crouse; Rounds, Kathleen A.

    2002-01-01

    Lesbian, gay, bisexual and transgender youth (LGBT) continue to face extreme discrimination within the school environment. Existing literature suggests that LGBT youth are at high risk for a number of health problems, including suicide ideation and attempts, harassment, substance abuse, homelessness, and declining school performance. This…

  4. A Harsh Environment Wireless Pressure Sensing Solution Utilizing High Temperature Electronics

    Science.gov (United States)

    Yang, Jie

    2013-01-01

    Pressure measurement under harsh environments, especially at high temperatures, is of great interest to many industries. The applicability of current pressure sensing technologies in extreme environments is limited by the embedded electronics which cannot survive beyond 300 °C ambient temperature as of today. In this paper, a pressure signal processing and wireless transmission module based on the cutting-edge Silicon Carbide (SiC) devices is designed and developed, for a commercial piezoresistive MEMS pressure sensor from Kulite Semiconductor Products, Inc. Equipped with this advanced high-temperature SiC electronics, not only the sensor head, but the entire pressure sensor suite is capable of operating at 450 °C. The addition of wireless functionality also makes the pressure sensor more flexible in harsh environments by eliminating the costly and fragile cable connections. The proposed approach was verified through prototype fabrication and high temperature bench testing from room temperature up to 450 °C. This novel high-temperature pressure sensing technology can be applied in real-time health monitoring of many systems involving harsh environments, such as military and commercial turbine engines. PMID:23447006

  5. Does Web-Based Role-Play Establish a High Quality Learning Environment? Design versus Evaluation

    Science.gov (United States)

    Ludewig, Alexandra; Ludewig-Rohwer, Iris

    2013-01-01

    Online role-plays have been celebrated for providing an environment which allows for high quality learning. Innovative approaches have been embraced in foreign language studies, especially in countries where a great distance to the target country needs to be overcome, not only to expose students to the target language but also to provide them with…

  6. Analysing High School Students' Participation and Interaction in an Asynchronous Online Project-Based Learning Environment

    Science.gov (United States)

    Lang, Quek Choon

    2010-01-01

    This study aims to replicate and extend a previous study which was conducted on primary school students' asynchronous online project-based learning. In this study, 276 high school students' participation and interaction in a project-based learning environment was mediated by an asynchronous computer-mediated communication (CMC) tool. The students'…

  7. Robust piezoelectric composites for energy harvesting in high-strain environments

    NARCIS (Netherlands)

    Ende, D.A. van der; Groen, W.A.; Zwaag, S. van der

    2013-01-01

    High-strain environments, such as are found in automobile tires, provide deformation energy that can be harvested using piezoelectric materials, for instance, for powering electronics such as wireless sensors. Despite numerous efforts, none of the present devices easily satisfy the stringent

  8. The Study Experiences of the High Achievers in a Competitive Academic Environment: A Cost of Success?

    Science.gov (United States)

    Nordmo, Ivar; Samara, Akylina

    2009-01-01

    The present paper is a case study that explores the study experiences and possible costs of success for the students accepted into the professional program in psychology at the University of Bergen in Norway. In this highly competitive environment, between 500 and 1000 students compete for 36 places during the introduction year. The study is based…

  9. Space Photovoltaic Research and Technology 1985: High Efficiency, Space Environment, and Array Technology

    Science.gov (United States)

    1985-01-01

    The seventh NASA Conference on Space Photovoltaic Research and Technology was held at NASA Lewis Research Center, Cleveland, Ohio, from 30 April until 2 May 1985. Its purpose was to assess the progress made, the problems remaining, and future strategy for space photovoltaic research. Particular emphasis was placed on high efficiency, space environment, and array technology.

  10. PRACTICAL ASPECTS FOR DEVELOPMENT OF INFORMATIONAL AND EDUCATIONAL ENVIRONMENT OF HIGH TECHNICAL SCHOOL

    Directory of Open Access Journals (Sweden)

    Sergey F. Rodionov

    2015-01-01

    Full Text Available The approach is offered to development of the informational and educational environment of high technical school,based on deep integration of electronic educational content with methods and tools for the engineering problemssolving. The application program interface (API is used asthe main integration instrument, which modern Its have.

  11. High-throughput sequencing of microRNAs in peripheral blood mononuclear cells: identification of potential weight loss biomarkers.

    Directory of Open Access Journals (Sweden)

    Fermín I Milagro

    Full Text Available INTRODUCTION: MicroRNAs (miRNAs are being increasingly studied in relation to energy metabolism and body composition homeostasis. Indeed, the quantitative analysis of miRNAs expression in different adiposity conditions may contribute to understand the intimate mechanisms participating in body weight control and to find new biomarkers with diagnostic or prognostic value in obesity management. OBJECTIVE: The aim of this study was the search for miRNAs in blood cells whose expression could be used as prognostic biomarkers of weight loss. METHODS: Ten Caucasian obese women were selected among the participants in a weight-loss trial that consisted in following an energy-restricted treatment. Weight loss was considered unsuccessful when 5% (responders. At baseline, total miRNA isolated from peripheral blood mononuclear cells (PBMC was sequenced with SOLiD v4. The miRNA sequencing data were validated by RT-PCR. RESULTS: Differential baseline expression of several miRNAs was found between responders and non-responders. Two miRNAs were up-regulated in the non-responder group (mir-935 and mir-4772 and three others were down-regulated (mir-223, mir-224 and mir-376b. Both mir-935 and mir-4772 showed relevant associations with the magnitude of weight loss, although the expression of other transcripts (mir-874, mir-199b, mir-766, mir-589 and mir-148b also correlated with weight loss. CONCLUSIONS: This research addresses the use of high-throughput sequencing technologies in the search for miRNA expression biomarkers in obesity, by determining the miRNA transcriptome of PBMC. Basal expression of different miRNAs, particularly mir-935 and mir-4772, could be prognostic biomarkers and may forecast the response to a hypocaloric diet.

  12. School lunch and snacking patterns among high school students: Associations with school food environment and policies

    OpenAIRE

    Story Mary; Hannan Peter J; French Simone A; Neumark-Sztainer Dianne; Fulkerson Jayne A

    2005-01-01

    Abstract Objectives This study examined associations between high school students' lunch patterns and vending machine purchases and the school food environment and policies. Methods A randomly selected sample of 1088 high school students from 20 schools completed surveys about their lunch practices and vending machine purchases. School food policies were assessed by principal and food director surveys. The number of vending machines and their hours of operation were assessed by trained resear...

  13. Genetic diversity loss associated to high mortality and environmental stress during the recruitment stage of a coral reef fish

    Science.gov (United States)

    Pini, J.; Planes, S.; Rochel, E.; Lecchini, D.; Fauvelot, C.

    2011-06-01

    We investigated the short-term impact of environmental-induced stress on survival and neutral genetic diversity of recently settled juveniles of a damselfish, Dascyllus aruanus, using spatiotemporal caging experiments in various natural environmental conditions in Moorea (French Polynesia). Juveniles' mortality was followed at five study sites and overall four experiments, mortality rates ranged from 0 to 45%. Mortality rate and average daily water temperature were positively correlated ( P = 0.018). Juveniles' mortality rate and allelic richness estimated from ten microsatellite loci were negatively correlated ( P = 0.046). Together, an overdominance of heterozygotes was observed within hostile environments. These results suggest that an allelic richness loss may be expected as a direct consequence of unfavorable environmental conditions. Thus, a worrisome scenario on demographic and genetic consequences may be expected from habitat degradation in the context of global change and human pressure increases.

  14. Enhanced magnetic domain relaxation frequency and low power losses in Zn2+ substituted manganese ferrites potential for high frequency applications

    Science.gov (United States)

    Praveena, K.; Chen, Hsiao-Wen; Liu, Hsiang-Lin; Sadhana, K.; Murthy, S. R.

    2016-12-01

    Nowadays electronic industries prerequisites magnetic materials, i.e., iron rich materials and their magnetic alloys. However, with the advent of high frequency applications, the standard techniques of reducing eddy current losses, using iron cores, were no longer efficient or cost effective. Current market trends of the switched mode power supplies industries required even low energy losses in power conversion with maintenance of adequate initial permeability. From the above point of view, in the present study we aimed at the production of Manganese-Zinc ferrites prepared via solution combustion method using mixture of fuels and achieved low loss, high saturation magnetization, high permeability, and high magnetic domain relaxation frequency. The as-synthesized Zn2+ substituted MnFe2O4 were characterized by X-ray diffractometer (XRD) and transmission electron microscopy (TEM). The fractions of Mn2+, Zn2+ and Fe2+ cations occupying tetrahedral sites along with Fe occupying octahedral sites within the unit cell of all ferrite samples were estimated by Raman scattering spectroscopy. The magnetic domain relaxation was investigated by inductance spectroscopy (IS) and the observed magnetic domain relaxation frequency (fr) was increased with the increase in grain size. The real and imaginary part of permeability (μ‧ and μ″) increased with frequency and showed a maximum above 100 MHz. This can be explained on the basis of spin rotation and domain wall motion. The saturation magnetization (Ms), remnant magnetization (Mr) and magneton number (μB) decreased gradually with increasing Zn2+ concentration. The decrease in the saturation magnetization was discussed with Yafet-Kittel (Y-K) model. The Zn2+ concentration increases the relative number of ferric ions on the A sites, reduces the A-B interactions. The frequency dependent total power losses decreased as the zinc concentration increased. At 1 MHz, the total power loss (Pt) changed from 358 mW/cm3 for x=0-165 mW/cm3

  15. Identification of six new Alternaria sulfoconjugated metabolites by high-resolution neutral loss filtering.

    Science.gov (United States)

    Kelman, Megan J; Renaud, Justin B; Seifert, Keith A; Mack, Jonathan; Sivagnanam, Kumaran; Yeung, Ken K-C; Sumarah, Mark W

    2015-10-15

    Many species of Alternaria damage important agricultural crops, including small grains and tomatoes. These fungi can produce a variety of secondary metabolites, some of which are toxic to humans and animals. Interest in screening for conjugated or 'modified' mycotoxins has increased because of their tendency to evade traditional analytical screening methods. Two sulfoconjugated Alternaria toxins have been reported and the potential exists for many more. One hundred and forty-eight Canadian strains of Alternaria spp., about half of them isolated from grain, were grown on Potato Dextrose Agar in Petri dishes for 7 days. Plugs of each strain were removed, extracted and screened by a rapid liquid chromatography (LC)/data-dependent tandem mass spectrometry (MS(2)) method in negative electrospray ionization mode. Data generated on an Orbitrap Q-Exactive mass spectrometer was processed by post-acquisition neutral loss filtering (NLF). Seven isolates that produced sulfoconjugates of known Alternaria toxins were selected for growth on three additional types of fermentation media. Collision-induced dissociation of sulfoconjugated ions displayed a distinctive neutral loss of SO3 (79.957 Da) that was detected in the MS(2) datasets using post-acquisition NLF. A total of 108 of the 148 isolates screened produced sulfoconjugated metabolites on agar plates. Analysis of the seven isolates grown in liquid culture, on rice and Cheerios, led to the discovery of six new, two previously reported and 30 unidentified sulfoconjugated compounds. NLF of HRMS(2) data from an Orbitrap Q-Exactive is a powerful tool for the rapid discovery of sulfoconjugated fungal metabolites. This technique could also be applied to the detection of other important conjugated mycotoxins such as glucosides. The majority of the Canadian isolates of Alternaria spp. studied produced sulfoconjugated metabolites, some of which had no known 'free' Alternaria precursor metabolite, indicating that they are possibly new

  16. The evaluation of geopolymer properties prepared by alkali activation of black coal ashes with high content of loss on ignition

    Directory of Open Access Journals (Sweden)

    Michalíková Františka

    2010-11-01

    Full Text Available The utilization of fly ashes in Slovakia is lower than in other countries and dumping of fly ashes prevails. The dumping changeschemical and phase composition of fly ashes and so it decreases possibilities for their utilization. Fly ashes are mainly used in buildingindustry, where the content of loss on ignition (LOI is limited due to standards. Black coal fly ashes produced in Slovakia have a highcontent of loss on ignition – more than 20 % - so they straight utilization in building industry is not possible. The current possibility fortheir utilization is in geopolymer synthesis. Products with 28-day compression strength of 35.7 MPa and 180-day compression strengthof 55.0 MPa were obtained by alkali activation of fly ashes with 23.25 % LOI with 8 wt% Na2O and their next hardening in temperatureof 80 °C during 6 hours. Products have a great frost-resistance and aggressive environments resistance (NaCl a H2SO4 solutions.

  17. Hypersonic engine component experiments in high heat flux, supersonic flow environment

    Science.gov (United States)

    Gladden, Herbert J.; Melis, Matthew E.

    1993-01-01

    A major concern in advancing the state-of-the-art technologies for hypersonic vehicles is the development of an aeropropulsion system capable of withstanding the sustained high thermal loads expected during hypersonic flight. Even though progress has been made in the computational understanding of fluid dynamics and the physics/chemistry of high speed flight, there is also a need for experimental facilities capable of providing a high heat flux environment for testing component concepts and verifying/calibrating these analyses. A hydrogen/oxygen rocket engine heat source was developed at the NASA Lewis Research Center as one element in a series of facilities at national laboratories designed to fulfill this need. This 'Hot Gas Facility' is capable of providing heat fluxes up to 450 w/sq cm on flat surfaces and up to 5,000 w/sq cm at the leading edge stagnation point of a strut in a supersonic flow stream. Gas temperatures up to 3050 K can also be attained. Two recent experimental programs conducted in this facility are discussed. The objective of the first experiment is to evaluate the erosion and oxidation characteristics of a coating on a cowl leading edge (or strut leading edge) in a supersonic, high heat flux environment. Macrophotographic data from a coated leading edge model show progressive degradation over several thermal cycles at aerothermal conditions representative of high Mach number flight. The objective of the second experiment is to assess the capability of cooling a porous surface exposed to a high temperature, high velocity flow environment and to provide a heat transfer data base for a design procedure. Experimental results from transpiration cooled surfaces in a supersonic flow environment are presented.

  18. Effects of external environment on thermocapillary convection of high prandtl number fluid

    Directory of Open Access Journals (Sweden)

    Liang Ruquan

    2016-01-01

    Full Text Available Numerical simulations have been carried out to investigate the influence of external environment on thermocapillary convection in high Prandtl number (Pr=68 liquid. The geometric model of physical problem is that the the liquid bridge surrounded by ambient air under zero or ground gravity. The interface velocity, temperature, heat flux and flow pattern in the liquid bridge are presented and discussed under different conditions by changing the external environment. The buoyancy convection produces a symmetrical vortex in the liquid bridge. The ambient air affects the distributions of the temperature velocity and heat flux on the interface by changing the thermocapillary convection.

  19. Braille reading : the influence of instructional strategies, the learning environment and the braille reading habits on the development of braille reading efficiency among the primary school pupils with total loss of vision in Kenya

    OpenAIRE

    Okungu, Phoebe Aoko

    2005-01-01

    Abstract This thesis is based on a study of Braille reading among the lower primary school pupils with total loss of vision in Kenya. The study was conducted in three special schools for pupils with visual impairments. In each school, the following were studied: The learning environment for grade three pupils, the instructional strategies applied by the teachers of English in those grades and Braille reading habits used by three pupils with total loss of vision. The aim of the thesis ...

  20. Diets with high or low protein content and glycemic index for weight-loss maintenance

    DEFF Research Database (Denmark)

    Larsen, Thomas Meinert; Dalskov, Stine-Mathilde; Baak, Marleen van

    2010-01-01

    Studies of weight-control diets that are high in protein or low in glycemic index have reached varied conclusions, probably owing to the fact that the studies had insufficient power.......Studies of weight-control diets that are high in protein or low in glycemic index have reached varied conclusions, probably owing to the fact that the studies had insufficient power....

  1. Highly doped InP as a low loss plasmonic material for mid-IR region

    DEFF Research Database (Denmark)

    Panah, Mohammad Esmail Aryaee; Takayama, Osamu; Morozov, S. V.

    2016-01-01

    We study plasmonic properties of highly doped InP in the mid-infrared (IR) range. InP was grown by metal-organic vapor phase epitaxy (MOVPE) with the growth conditions optimized to achieve high free electron concentrations by doping with silicon. The permittivity of the grown material was found b...

  2. Persistent humoral immune defect in highly active antiretroviral therapy-treated children with HIV-1 infection: loss of specific antibodies against attenuated vaccine strains and natural viral infection

    NARCIS (Netherlands)

    Bekker, Vincent; Scherpbier, Henriëtte; Pajkrt, Dasja; Jurriaans, Suzanne; Zaaijer, Hans; Kuijpers, Taco W.

    2006-01-01

    OBJECTIVE: In the pre-highly active antiretroviral therapy era, a loss of specific antibodies was seen. Our objective with this study was to describe the loss of specific antibodies during treatment with highly active antiretroviral therapy. METHODS: In a prospective, single-center, cohort study of

  3. High School Students' Recommendations to Improve School Food Environments: Insights From a Critical Stakeholder Group.

    Science.gov (United States)

    Asada, Yuka; Hughes, Alejandro G; Read, Margaret; Schwartz, Marlene B; Chriqui, Jamie F

    2017-11-01

    The Healthy, Hunger-Free Kids Act of 2010 (HHFKA) directed the US Department of Agriculture (USDA) to revise school meal standards. Students are most affected by efforts to improve the school food environment; yet, few studies directly include students. This study examined high school students' experiences of school meal reform to gain insight into implementation recommendations. We conducted 5 focus groups with high school students (N = 15) from high schools across 9 states. We also conducted follow-up interviews to further explore personal experiences. Focus groups and interview transcripts were coded and organized in Atlas.ti v7 by analysts, following principles of constant comparative analysis. Students reported overall positive perceptions of the revised school meal standards and supported continued efforts to improve the food environment. Recommendations to improve the food environment included engaging students, focusing on the quality and palatability of meal items, moving toward scratch-cooking, and addressing cafeteria infrastructure. Students' recommendations point to opportunities where school districts, as well as local, state, and federal organizations can work to improve the school food environment. Their insights are directly relevant to USDA's recently released Local School Wellness Policy final rule, of which school meal standards are one provision. © 2017, American School Health Association.

  4. Spectral emissivity of candidate alloys for very high temperature reactors in high temperature air environment

    Energy Technology Data Exchange (ETDEWEB)

    Cao, G., E-mail: gcao@wisc.edu; Weber, S.J.; Martin, S.O.; Sridharan, K.; Anderson, M.H.; Allen, T.R.

    2013-10-15

    Emissivity measurements for candidate alloys for very high temperature reactors were carried out in a custom-built experimental facility, capable of both efficient and reliable measurements of spectral emissivities of multiple samples at high temperatures. The alloys studied include 304 and 316 austenitic stainless steels, Alloy 617, and SA508 ferritic steel. The oxidation of alloys plays an important role in dictating emissivity values. The higher chromium content of 304 and 316 austenitic stainless steels, and Alloy 617 results in an oxide layer only of sub-micron thickness even at 700 °C and consequently the emissivity of these alloys remains low. In contrast, the low alloy SA508 ferritic steel which contains no chromium develops a thicker oxide layer, and consequently exhibits higher emissivity values.

  5. Spectral emissivity of candidate alloys for very high temperature reactors in high temperature air environment

    Science.gov (United States)

    Cao, G.; Weber, S. J.; Martin, S. O.; Sridharan, K.; Anderson, M. H.; Allen, T. R.

    2013-10-01

    Emissivity measurements for candidate alloys for very high temperature reactors were carried out in a custom-built experimental facility, capable of both efficient and reliable measurements of spectral emissivities of multiple samples at high temperatures. The alloys studied include 304 and 316 austenitic stainless steels, Alloy 617, and SA508 ferritic steel. The oxidation of alloys plays an important role in dictating emissivity values. The higher chromium content of 304 and 316 austenitic stainless steels, and Alloy 617 results in an oxide layer only of sub-micron thickness even at 700 °C and consequently the emissivity of these alloys remains low. In contrast, the low alloy SA508 ferritic steel which contains no chromium develops a thicker oxide layer, and consequently exhibits higher emissivity values.

  6. Micromegas a high-granularity position-sensitive gaseous detector for high particle-flux environments

    CERN Document Server

    Giomataris, Ioanis; Robert, J P; Charpak, Georges

    1996-01-01

    We describe a novel structure for a gaseous detector that is under development at Saclay. It consists of a two-stage parallel-plate avalanche chamber of small amplification gap (100 microm) combined with a conversion-drift space. It allows a fast removal of positive ionsproduced during the avalanche development. Fast signals (3/4 1 ns) are obtained duirng the collection of the electron avalanche on the anode microstrip plane. The induced positive ion signal has a rise time of 100 ns. The fast evacuation of positive ions combined with the high granularity of the detector provide a high rate capability. Gas gains of up to $10^5$ have been achieved.

  7. Construct validity of Comprehensive High-Level Activity Mobility Predictor (CHAMP) for male servicemembers with traumatic lower-limb loss.

    Science.gov (United States)

    Gailey, Robert S; Scoville, Charles; Gaunaurd, Ignacio A; Raya, Michele A; Linberg, Alison A; Stoneman, Paul D; Campbell, Stuart M; Roach, Kathryn E

    2013-01-01

    This study examined the convergent construct validity of a new performance-based assessment instrument called the Comprehensive High-Level Activity Mobility Predictor (CHAMP) as a measure of high-level mobility in servicemembers (SMs) with traumatic lower-limb loss (LLL). The study was completed by 118 SMs. Convergent construct validity of the CHAMP was established using the 6-minute walk test (6MWT) as a measure of overall mobility and physical function and the Amputee Mobility Predictor (AMP) as a measure of basic prosthetic mobility. The known group methods construct validity examined disparities in high-level mobility capability among SMs with different levels of LLL. The CHAMP score demonstrated a strong positive relationship between 6MWT distance (r = 0.80, p CHAMP can discriminate between different levels of LLL. Study findings support the CHAMP as a valid performance-based assessment instrument of high-level mobility for SMs with traumatic LLL.

  8. Electronic environments of ferrous iron in rhyolitic and basaltic glasses at high pressure: Silicate Glasses at High Pressure

    Energy Technology Data Exchange (ETDEWEB)

    Solomatova, Natalia V. [Division of Geological and Planetary Sciences, Caltech, Pasadena California USA; Jackson, Jennifer M. [Division of Geological and Planetary Sciences, Caltech, Pasadena California USA; Sturhahn, Wolfgang [Division of Geological and Planetary Sciences, Caltech, Pasadena California USA; Rossman, George R. [Division of Geological and Planetary Sciences, Caltech, Pasadena California USA; Roskosz, Mathieu [IMPMC-Muséum National d' Histoire Naturelle-CNRS, Paris France

    2017-08-01

    The physical properties of silicate melts within Earth's mantle affect the chemical and thermal evolution of its interior. Chemistry and coordination environments affect such properties. We have measured the hyperfine parameters of iron-bearing rhyolitic and basaltic glasses up to ~120 GPa and ~100 GPa, respectively, in a neon pressure medium using time domain synchrotron Mössbauer spectroscopy. The spectra for rhyolitic and basaltic glasses are well explained by three high-spin Fe2+-like sites with distinct quadrupole splittings. Absence of detectable ferric iron was confirmed with optical absorption spectroscopy. The sites with relatively high and intermediate quadrupole splittings are likely a result of fivefold and sixfold coordination environments of ferrous iron that transition to higher coordination with increasing pressure. The ferrous site with a relatively low quadrupole splitting and isomer shift at low pressures may be related to a fourfold or a second fivefold ferrous iron site, which transitions to higher coordination in basaltic glass, but likely remains in low coordination in rhyolitic glass. These results indicate that iron experiences changes in its coordination environment with increasing pressure without undergoing a high-spin to low-spin transition. We compare our results to the hyperfine parameters of silicate glasses of different compositions. With the assumption that coordination environments in silicate glasses may serve as a good indicator for those in a melt, this study suggests that ferrous iron in chemically complex silicate melts likely exists in a high-spin state throughout most of Earth's mantle.

  9. Silicon-Carbide Power MOSFET Performance in High Efficiency Boost Power Processing Unit for Extreme Environments

    Science.gov (United States)

    Ikpe, Stanley A.; Lauenstein, Jean-Marie; Carr, Gregory A.; Hunter, Don; Ludwig, Lawrence L.; Wood, William; Del Castillo, Linda Y.; Fitzpatrick, Fred; Chen, Yuan

    2016-01-01

    Silicon-Carbide device technology has generated much interest in recent years. With superior thermal performance, power ratings and potential switching frequencies over its Silicon counterpart, Silicon-Carbide offers a greater possibility for high powered switching applications in extreme environment. In particular, Silicon-Carbide Metal-Oxide- Semiconductor Field-Effect Transistors' (MOSFETs) maturing process technology has produced a plethora of commercially available power dense, low on-state resistance devices capable of switching at high frequencies. A novel hard-switched power processing unit (PPU) is implemented utilizing Silicon-Carbide power devices. Accelerated life data is captured and assessed in conjunction with a damage accumulation model of gate oxide and drain-source junction lifetime to evaluate potential system performance at high temperature environments.

  10. Impact of a combined high cholesterol diet and high glucose environment on vasculature.

    Directory of Open Access Journals (Sweden)

    Zemin Wang

    Full Text Available AIMS: Vascular complications are the leading cause of mortality and morbidity in patients with diabetes. However, proper animal models of diabetic vasculopathy that recapitulate the accelerated progression of vascular lesions in human are unavailable. In the present study, we developed a zebrafish model of diabetic vascular complications and the methodology for quantifying vascular lesion formation real-time in the living diabetic zebrafish. METHODS AND RESULTS: Wild type zebrafish (AB and transgenic zebrafish lines of fli1:EGFP, lyz:EGFP, gata1:dsRed, double transgenic zebrafish of gata1:dsRed/fli1:EGFP were exposed to high cholesterol diet and 3% glucose (HCD-HG for 10 days. The zebrafish model with HCD-HG treatment was characterized by significantly increased tissue levels of insulin, glucagon, glucose, total triglyceride and cholesterol. Confocal microscopic analysis further revealed that the diabetic larvae developed clearly thickened endothelial layers, distinct perivascular lipid depositions, substantial accumulations of inflammatory cells in the injured vasculature, and a decreased velocity of blood flow. Moreover, the vascular abnormalities were improved by the treatment of pioglitazone and metformin. CONCLUSION: A combination of high cholesterol diet and high glucose exposure induces a rapid onset of vascular complications in zebrafish similar to the early atherosclerotic vascular injuries in mammalian diabetic models, suggesting that zebrafish may be used as a novel animal model for diabetic vasculopathy.

  11. Astroglial Pentose Phosphate Pathway Rates in Response to High-Glucose Environments

    Directory of Open Access Journals (Sweden)

    Shinichi Takahashi

    2012-02-01

    Full Text Available ROS (reactive oxygen species play an essential role in the pathophysiology of diabetes, stroke and neurodegenerative disorders. Hyperglycaemia associated with diabetes enhances ROS production and causes oxidative stress in vascular endothelial cells, but adverse effects of either acute or chronic high-glucose environments on brain parenchymal cells remain unclear. The PPP (pentose phosphate pathway and GSH participate in a major defence mechanism against ROS in brain, and we explored the role and regulation of the astroglial PPP in response to acute and chronic high-glucose environments. PPP activity was measured in cultured neurons and astroglia by determining the difference in rate of 14CO2 production from [1-14C]glucose and [6-14C]glucose. ROS production, mainly H2O2, and GSH were also assessed. Acutely elevated glucose concentrations in the culture media increased PPP activity and GSH level in astroglia, decreasing ROS production. Chronically elevated glucose environments also induced PPP activation. Immunohistochemical analyses revealed that chronic high-glucose environments induced ER (endoplasmic reticulum stress (presumably through increased hexosamine biosynthetic pathway flux. Nuclear translocation of Nrf2 (nuclear factor-erythroid 2 p45 subunit-related factor 2, which regulates G6PDH (glyceraldehyde-6-phosphate dehydrogenase by enhancing transcription, was also observed in association with BiP (immunoglobulin heavy-chain-binding protein expression. Acute and chronic high-glucose environments activated the PPP in astroglia, preventing ROS elevation. Therefore a rapid decrease in glucose level seems to enhance ROS toxicity, perhaps contributing to neural damage when insulin levels given to diabetic patients are not properly calibrated and plasma glucose levels are not adequately maintained. These findings may also explain the lack of evidence for clinical benefits from strict glycaemic control during the acute phase of stroke.

  12. Secure Enclaves: An Isolation-centric Approach for Creating Secure High Performance Computing Environments

    Energy Technology Data Exchange (ETDEWEB)

    Aderholdt, Ferrol [Tennessee Technological Univ., Cookeville, TN (United States); Caldwell, Blake A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hicks, Susan Elaine [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Koch, Scott M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Naughton, III, Thomas J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Pelfrey, Daniel S. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Pogge, James R [Tennessee Technological Univ., Cookeville, TN (United States); Scott, Stephen L [Tennessee Technological Univ., Cookeville, TN (United States); Shipman, Galen M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Sorrillo, Lawrence [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-01-01

    High performance computing environments are often used for a wide variety of workloads ranging from simulation, data transformation and analysis, and complex workflows to name just a few. These systems may process data at various security levels but in so doing are often enclaved at the highest security posture. This approach places significant restrictions on the users of the system even when processing data at a lower security level and exposes data at higher levels of confidentiality to a much broader population than otherwise necessary. The traditional approach of isolation, while effective in establishing security enclaves poses significant challenges for the use of shared infrastructure in HPC environments. This report details current state-of-the-art in virtualization, reconfigurable network enclaving via Software Defined Networking (SDN), and storage architectures and bridging techniques for creating secure enclaves in HPC environments.

  13. Crowd Behaviour during High-Stress Evacuations in an Immersive Virtual Environment

    CERN Document Server

    Moussaïd, Mehdi; Thrash, Tyler; Sumner, Robert W; Gross, Markus; Helbing, Dirk; Hölscher, Christoph

    2016-01-01

    Understanding the collective dynamics of crowd movements during stressful emergency situations is central to reducing the risk of deadly crowd disasters. Yet, their systematic experimental study remains a challenging open problem due to ethical and methodological constraints. In this paper, we demonstrate the viability of shared 3D virtual environments as an experimental platform for conducting crowd experiments with real people. In particular, we show that crowds of real human subjects moving and interacting in an immersive 3D virtual environment exhibit typical patterns of real crowds as observed in real-life crowded situations. These include the manifestation of social conventions and the emergence of self-organized patterns during egress scenarios. High-stress evacuation experiments conducted in this virtual environment reveal movements characterized by mass herding and dangerous overcrowding as they occur in crowd disasters. We describe the behavioral mechanisms at play under such extreme conditions and ...

  14. Gene-environment interaction in the onset of eczema in infancy: filaggrin loss-of-function mutations enhanced by neonatal cat exposure.

    Directory of Open Access Journals (Sweden)

    Hans Bisgaard

    2008-06-01

    Full Text Available BACKGROUND: Loss-of-function variants in the gene encoding filaggrin (FLG are major determinants of eczema. We hypothesized that weakening of the physical barrier in FLG-deficient individuals may potentiate the effect of environmental exposures. Therefore, we investigated whether there is an interaction between FLG loss-of-function mutations with environmental exposures (pets and dust mites in relation to the development of eczema. METHODS AND FINDINGS: We used data obtained in early life in a high-risk birth cohort in Denmark and replicated the findings in an unselected birth cohort in the United Kingdom. Primary outcome was age of onset of eczema; environmental exposures included pet ownership and mite and pet allergen levels. In Copenhagen (n = 379, FLG mutation increased the risk of eczema during the first year of life (hazard ratio [HR] 2.26, 95% confidence interval [CI] 1.27-4.00, p = 0.005, with a further increase in risk related to cat exposure at birth amongst children with FLG mutation (HR 11.11, 95% CI 3.79-32.60, p < 0.0001; dog exposure was moderately protective (HR 0.49, 95% CI 0.24-1.01, p = 0.05, but not related to FLG genotype. In Manchester (n = 503 an independent and significant association of the development of eczema by age 12 mo with FLG genotype was confirmed (HR 1.95, 95% CI 1.13-3.36, p = 0.02. In addition, the risk increased because of the interaction of cat ownership at birth and FLG genotype (HR 3.82, 95% CI 1.35-10.81, p = 0.01, with no significant effect of the interaction with dog ownership (HR 0.59, 95% CI 0.16-2.20, p = 0.43. Mite-allergen had no effects in either cohort. The observed effects were independent of sensitisation. CONCLUSIONS: We have demonstrated a significant interaction between FLG loss-of-function main mutations (501x and 2282del4 and cat ownership at birth on the development of early-life eczema in two independent birth cohorts. Our data suggest that cat but not dog ownership substantially

  15. Meal pattern alterations associated with intermittent fasting for weight loss are normalized after high-fat diet re-feeding.

    Science.gov (United States)

    Gotthardt, Juliet D; Bello, Nicholas T

    2017-05-15

    Alternate day, intermittent fasting (IMF) can be an effective weight loss strategy. However, the effects of IMF on eating behaviors are not well characterized. We investigated the acute and residual effects of IMF for weight loss on meal patterns in adult obese male C57BL/6 mice. After 8weeks of ad libitum high-fat diet to induce diet-induced obesity (DIO), mice were either continued on ad libitum high-fat diet (HFD) or placed on one of 5 diet strategies for weight loss: IMF of high-fat diet (IMF-HFD), pair-fed to IMF-HFD group (PF-HFD), ad libitum low-fat diet (LFD), IMF of low-fat diet (IMF-LFD), or pair-fed to IMF-LFD group (PF-LFD). After the 4-week diet period, all groups were refed the high-fat diet for 6weeks. By the end of the diet period, all 5 groups had lost weight compared with HFD group, but after 6weeks of HFD re-feeding all groups had similar body weights. On (Day 2) of the diet period, IMF-HFD had greater first meal size and faster eating rate compared with HFD. Also, first meal duration was greater in LFD and IMF-LFD compared with HFD. At the end of the diet period (Day 28), the intermittent fasting groups (IMF-HFD and IMF-LFD) had greater first meal sizes and faster first meal eating rate compared with their respective ad libitum fed groups on similar diets (HFD and LFD). Also, average meal duration was longer on Day 28 in the low-fat diet groups (LFD and IMF-LFD) compared with high-fat diet groups (HFD and IMF-HFD). After 6weeks of HFD re-feeding (Day 70), there were no differences in meal patterns in groups that had previously experienced intermittent fasting compared with ad libitum fed groups. These findings suggest that meal patterns are only transiently altered during alternate day intermittent fasting for weight loss in obese male mice. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Overhead high-voltage lines - a electromagnetic environment restrictions on use areas

    Directory of Open Access Journals (Sweden)

    Jacek Paś

    2014-09-01

    Full Text Available The paper presents the influence of exploitation of high voltage overhead lines in the vicinity of the lands that are intended for built-up areas. Near distribution stations and high voltage overhead lines can be present some physical and chemical factors which under certain conditions and at their high levels will be inconvenient to the environment. The environmental impacts of these factors are complex problems which are analysed both in technical and biological-medical aspects. [b]Keywords[/b]: overhead lines, electric field and magnetic, lines of force

  17. Graphene oxide as a high-performance fluid-loss-control additive in water-based drilling fluids.

    Science.gov (United States)

    Kosynkin, Dmitry V; Ceriotti, Gabriel; Wilson, Kurt C; Lomeda, Jay R; Scorsone, Jason T; Patel, Arvind D; Friedheim, James E; Tour, James M

    2012-01-01

    Graphene oxide (GO) performs well as a filtration additive in water-based drilling fluids at concentrations as low as 0.2 % (w/w) by carbon content. Standard American Petroleum Institute (API) filtration tests were conducted on pH-adjusted, aqueous dispersions of GO and xanthan gum. It was found that a combination of large-flake GO and powdered GO in a 3:1 ratio performed best in the API tests, allowing an average fluid loss of 6.1 mL over 30 min and leaving a filter cake ~20 μm thick. In comparison, a standard suspension (~12 g/L) of clays and polymers used in the oil industry gave an average fluid loss of 7.2 mL and a filter cake ~280 μm thick. Scanning electron microscopy imaging revealed the extreme pliability of well-exfoliated GO, as the pressure due to filtration crumpled single GO sheets, forcing them to slide through pores with diameters much smaller than the flake's flattened size. GO solutions also exhibited greater shear thinning and higher temperature stability compared to clay-based fluid-loss additives, demonstrating potential for high-temperature well applications. © 2011 American Chemical Society

  18. The comparison of effects of high protein-low fat diet, and standard diet on weight loss

    Directory of Open Access Journals (Sweden)

    ebrahim Falahi

    2009-11-01

    Full Text Available Background: Obesity is one of the most important problems in the world. Suitable low calorie diets are among the best ways for weight loss. The aim of this study was to determine the effects and comparison of two kinds of low-calorie diets on weight loss. Materials and Methods: Seventy- six health women (20-55 yrs old were randomly divided into two groups for 3 months: 39 subjects in standard diet group (SD (carbohydrate 55%, fat 30%, protein 15%, and 37 persons in high protein-low fat diet group (HPD (carbohydrate 55%, fat 20%, protein 25%. Energy intake was 1000 kcal less than the daily needs in the two groups. In the beginning and at the end of each month the subjects were visited and food diet energy was adjusted. In the beginning and finally BMI, waist circumference, hip circumference, and waist to hip ratio were measured. Results: BMI decreased 4. 43±0.96 v. s 4. 15±0.76 in SD and HPD groups, respectively. The amount of weight loss was 10. 89 2.04 in SD and 10. 48 1.73 in HPD. Waist to hip ratio decreased 0. 02±0.014 v. s 0. 018±0. 014 in SD and HPD, respectively. For all variables there was no significant difference between two groups. Conclusion: Both low calorie diets (SD and HPD decreased weight and other obesity indices. Therefore, HPD may be a suitable substitution for standard diet.

  19. Early Foetal Loss Correlates Positively with Seroconversion against Mycobacterium avium paratuberculosis in High-Producing Dairy Cows.

    Science.gov (United States)

    Garcia-Ispierto, I; López-Gatius, F

    2016-04-01

    This study was designed to examine (i) the seroprevalence of Mycobacterium avium subs paratuberculosis (MAP) in a high-producing dairy herd with clinical symptoms of bovine paratuberculosis, (ii) MAP seroconversion and seronegativation dynamics in the herd and (iii) possible relationships between MAP infection status and herd reproductive performance. One single blood test per cow was performed early post-partum on a monthly basis from day 10-40 post-partum during the first year of the study in 519 cows belonging to a commercial dairy herd. A subset of 111 cows that became pregnant during the study was tested again 60-200 days later during the early foetal period, immediately after the first confirmation of gestation at 58-64 days post-AI. Logistic regression analysis indicated no effect of any independent variable on MAP seropositivity and conception rate 28-34 days post-AI. MAP seropositivity was not a factor affecting the anoestrous, subfertility and early foetal loss rates. In the subset of 111 cows, animals that seroconverted had a 3.9 times greater risk of suffering from early foetal loss (30.3%, 10/33) than the remaining pregnant animals (10.3%, 8/78), (95% confidence interval: 1.11-13.4; p = 0.003). In conclusion, early foetal loss was positively correlated with seroconversion to MAP. Reproductive performance was not impaired by MAP infection. © 2016 Blackwell Verlag GmbH.

  20. Time Is Money: The Decision Making of Smartphone High Users in Gain and Loss Intertemporal Choice

    Science.gov (United States)

    Tang, Zixuan; Zhang, Huijun; Yan, An; Qu, Chen

    2017-01-01

    Nowadays the smartphone plays an important role in our lives. While it brings us convenience and efficiency, its overuse can cause problems. Although a great number of studies have demonstrated that people affected by substance abuse, pathological gambling, and internet addiction disorder have lower self-control than average, scarcely any study has investigated the decision making of smartphone high users by using a behavioral paradigm. The present study employed an intertemporal task, the Smartphone Addiction Inventory (SPAI) and the Barratt Impulsiveness Scale 11th version (BIS-11) to explore the decision control of smartphone high users in a sample of 125 college students. Participants were divided into three groups according to their SPAI scores. The upper third (69 or higher), middle third (from 61 to 68) and lower third (60 or lower) of scores were defined as high smartphone users, medium users and low users, respectively. We compared the percentage of small immediate reward/penalty choices in different conditions between the three groups. Relative to the low users group, high users and medium users were more inclined to request an immediate monetary reward. Moreover, for the two dimensions of time and money in intertemporal choice, high users and medium users showed a bias in intertemporal choice task among most of the time points and value magnitude compared to low users. These findings demonstrated that smartphone overuse was associated with problematic decision-making, a pattern similar to that seen in persons affected by a variety of addictions. PMID:28344568

  1. Time Is Money: The Decision Making of Smartphone High Users in Gain and Loss Intertemporal Choice.

    Science.gov (United States)

    Tang, Zixuan; Zhang, Huijun; Yan, An; Qu, Chen

    2017-01-01

    Nowadays the smartphone plays an important role in our lives. While it brings us convenience and efficiency, its overuse can cause problems. Although a great number of studies have demonstrated that people affected by substance abuse, pathological gambling, and internet addiction disorder have lower self-control than average, scarcely any study has investigated the decision making of smartphone high users by using a behavioral paradigm. The present study employed an intertemporal task, the Smartphone Addiction Inventory (SPAI) and the Barratt Impulsiveness Scale 11th version (BIS-11) to explore the decision control of smartphone high users in a sample of 125 college students. Participants were divided into three groups according to their SPAI scores. The upper third (69 or higher), middle third (from 61 to 68) and lower third (60 or lower) of scores were defined as high smartphone users, medium users and low users, respectively. We compared the percentage of small immediate reward/penalty choices in different conditions between the three groups. Relative to the low users group, high users and medium users were more inclined to request an immediate monetary reward. Moreover, for the two dimensions of time and money in intertemporal choice, high users and medium users showed a bias in intertemporal choice task among most of the time points and value magnitude compared to low users. These findings demonstrated that smartphone overuse was associated with problematic decision-making, a pattern similar to that seen in persons affected by a variety of addictions.

  2. Rust Formation Mechanism on Low Alloy Steels after Exposure Test in High Cl− and High SOx Environment

    Science.gov (United States)

    Nishimura, Toshiyasu

    2017-01-01

    Exposure tests were performed on low alloy steels in high Cl− and high SOx environment, and the structure of the rust were analyzed by TEM (Transmission Electron Microscopy) and Raman Spectroscopy. In the exposure test site, the concentrations of Cl− and SOx were found to be high, which caused the corrosion of the steels. The conventional weathering steel (SMA: 0.6% Cr-0.4% Cu-Fe) showed higher corrosion resistance as compared to the carbon steel (SM), and Ni bearing steel exhibited the highest one. Raman spectroscopy showed that the inner rust of Ni bearing steel was mainly composed of α-FeOOH and spinel oxides. On the other hand, SMA contained β- and γ-FeOOH in inner rust, which increased the corrosion. TEM showed that nano-scale complex iron oxides containing Ni or Cr were formed in the rust on the low alloy steels, which suppressed the corrosion of steels in high Cl− and high SOx environment. PMID:28772560

  3. Influence of partial ionization on the energy loss of fast ions in high- Z material

    Energy Technology Data Exchange (ETDEWEB)

    Peter, T. (Max-Planck-Institut fuer Chemie, D-6500 Mainz, Germany (DE)); Kaercher, B. (Max-Planck-Institut fuer Quantenoptik, D-8046 Garching, Germany (DE))

    1991-04-01

    Analytical and simple numerical calculations of the stopping power of partially ionized high-{ital Z} targets are presented. Up to now such calculations are difficult, mainly because of lacking precise average ionization potentials of the target ions. The aim of this paper is both to clarify the importance of a suitable treatment of target ions in different ionization stages and to show by means of general scaling laws and explicit examples, that high-{ital Z} plasmas of high density and low ionization degree may have smaller stopping powers than cold matter. The resulting range lengthening of the projectile ions might be of crucial importance for a proper design of pellets in inertial confinement fusion.

  4. High incidence of allelic loss at 16q12.2 region spanning RBL2/p130 gene in retinoblastoma.

    Science.gov (United States)

    Priya, Kadam; Jada, Srinivasa Rao; Quah, Boon Long; Quah, Thuan Chong; Lai, Poh San

    2009-04-01

    Retinoblastoma (Rb) is the most common intra-ocular tumor that manifests in early childhood. It is initiated by the inactivation of RB1/p105 gene, a prototype tumor suppressor gene. However, observed recurrent chromosomal aberrations accompanying RB1/p105 mutations suggest the involvement of additional mutational events. Chromosome 16q is one of the loci with recurrent losses which are likely to contain tumor suppressor genes. In this study, allelic loss was demonstrated at a second locus for retinoblastoma, RBL2/p130 on 16q12.2. Using intragenic single nucleotide polymorphisms (SNPs) (rs1074182 and rs10748) and flanking extragenic microsatellite markers (D16S411 and D16S408), 40 retinoblastoma tumor samples were analyzed. Loss of heterozygosity (LOH) of these markers was found in 11 (57.9%) out of 19 informative tumors at the RBL2/p130 gene locus and while a total of 15 (78.9%) tumors showed LOH in at least one marker. Deletions extending more than 13 cM across the pericentromeric region of 16q12.1-q13 were inferred from four tumors. Microsatellite instability was observed in two other tumors at the flanking markers. No mutations were found in RBL2/p130 exons 19-22 coding for the protein domain critical for biological activity. This is the first evidence of LOH within RBL2/p130 gene in retinoblastoma. The high frequency of allelic loss provides further evidence on the implication of this gene in retinoblastoma development and/or progression.

  5. The fate of high redshift massive compact galaxies in dense environments

    Energy Technology Data Exchange (ETDEWEB)

    Kaufmann, Tobias; /Zurich, ETH; Mayer, Lucio; /Zurich U.; Carollo, Marcella; /Zurich, ETH; Feldmann, Robert; /Fermilab /Chicago U., KICP

    2012-01-01

    Massive compact galaxies seem to be more common at high redshift than in the local universe, especially in denser environments. To investigate the fate of such massive galaxies identified at z {approx} 2 we analyse the evolution of their properties in three cosmological hydrodynamical simulations that form virialized galaxy groups of mass {approx} 10{sup 13} M{sub {circle_dot}} hosting a central massive elliptical/S0 galaxy by redshift zero. We find that at redshift {approx} 2 the population of galaxies with M{sub *} > 2 x 10{sup 10} M{sub {circle_dot}} is diverse in terms of mass, velocity dispersion, star formation and effective radius, containing both very compact and relatively extended objects. In each simulation all the compact satellite galaxies have merged into the central galaxy by redshift 0 (with the exception of one simulation where one of such satellite galaxy survives). Satellites of similar mass at z = 0 are all less compact than their high redshift counterparts. They form later than the galaxies in the z = 2 sample and enter the group potential at z < 1, when dynamical friction times are longer than the Hubble time. Also, by z = 0 the central galaxies have increased substantially their characteristic radius via a combination of in situ star formation and mergers. Hence in a group environment descendants of compact galaxies either evolve towards larger sizes or they disappear before the present time as a result of the environment in which they evolve. Since the group-sized halos that we consider are representative of dense environments in the {Lambda}CDM cosmology, we conclude that the majority of high redshift compact massive galaxies do not survive until today as a result of the environment.

  6. Crowd behaviour during high-stress evacuations in an immersive virtual environment.

    Science.gov (United States)

    Moussaïd, Mehdi; Kapadia, Mubbasir; Thrash, Tyler; Sumner, Robert W; Gross, Markus; Helbing, Dirk; Hölscher, Christoph

    2016-09-01

    Understanding the collective dynamics of crowd movements during stressful emergency situations is central to reducing the risk of deadly crowd disasters. Yet, their systematic experimental study remains a challenging open problem due to ethical and methodological constraints. In this paper, we demonstrate the viability of shared three-dimensional virtual environments as an experimental platform for conducting crowd experiments with real people. In particular, we show that crowds of real human subjects moving and interacting in an immersive three-dimensional virtual environment exhibit typical patterns of real crowds as observed in real-life crowded situations. These include the manifestation of social conventions and the emergence of self-organized patterns during egress scenarios. High-stress evacuation experiments conducted in this virtual environment reveal movements characterized by mass herding and dangerous overcrowding as they occur in crowd disasters. We describe the behavioural mechanisms at play under such extreme conditions and identify critical zones where overcrowding may occur. Furthermore, we show that herding spontaneously emerges from a density effect without the need to assume an increase of the individual tendency to imitate peers. Our experiments reveal the promise of immersive virtual environments as an ethical, cost-efficient, yet accurate platform for exploring crowd behaviour in high-risk situations with real human subjects. © 2016 The Authors.

  7. Daily high doses of fluoxetine for weight loss and improvement in lifestyle before bariatric surgery

    NARCIS (Netherlands)

    Dolfing, JG; Wolffenbuttel, BHR; Oei, HI; ten Hoor-Aukerna, NM; Schweitzer, DH

    Background: The number of gastric restrictive bariatric operations is increasing each year, but about one-fifth of patients will become disappointed due to unsatisfactory weight reduction or annoying complications. We questioned whether weight reduction by taking high doses of fluoxetine improves

  8. Plasma pressure and particle loss studies in the Pilot-PSI high flux linear plasma generator

    NARCIS (Netherlands)

    Jesko, K.; van der Meiden, H. J.; Gunn, J. P.; Vernimmen, J. W. M.; De Temmerman, G.

    2017-01-01

    Plasma detachment in tokamak divertors reduces the particle and power fluxes to the plasma facing components and is essential for successful operation of ITER. The linear plasma generator Pilot-PSI can produce a high density (∼1021 m−3), low temperature (∼1 eV) plasma which is similar to that

  9. Low nutrient availability reduces high-irradiance–induced viability loss inoceanic phytoplankton

    NARCIS (Netherlands)

    Kulk, G.; van de Poll, W.H.; Visser, R.J.W.; Buma, A.G.J.

    2013-01-01

    In situ viability of oceanic phytoplankton may be relatively low in open oceans. This is assumed to be related to the high-irradiance and low-nutrient conditions typical for oligotrophic regions. However, experimental evidence for this phenomenon was not yet available. In the present study, the

  10. Hidden Losses: How Demographics Can Encourage Incorrect Assumptions about ESL High School Students' Success

    Science.gov (United States)

    Toohey, Kelleen; Derwing, Tracey M.

    2008-01-01

    Data from ESL students' records in Vancouver are examined in the light of the BC Ministry of Education's claim that ESL high school students are more successful than students whose first language is English. We argue that the academic achievement of well-to-do students whose parents are skilled workers or entrepreneurs may mask the completion…

  11. Low-loss electron beam transport in a high-power, electrostatic free-electron maser

    NARCIS (Netherlands)

    Valentini, M.; van der Geer, C. A. J.; Verhoeven, A. G. A.; van der Wiel, M. J.; Urbanus, W. H.

    1997-01-01

    At the FOM Institute for Plasma Physics ''Rijnhuizen'', The Netherlands, the commissioning of a high-power, electrostatic free-electron maser is in progress. The design target is the generation of 1 MW microwave power in the frequency range 130-260 GHz. The foreseen application

  12. Comparison of high protein and high fiber weight-loss diets in women with risk factors for the metabolic syndrome: a randomized trial

    Directory of Open Access Journals (Sweden)

    Williams Sheila M

    2011-04-01

    Full Text Available Abstract Background Studies have suggested that moderately high protein diets may be more appropriate than conventional low-fat high carbohydrate diets for individuals at risk of developing the metabolic syndrome and type 2 diabetes. However in most such studies sources of dietary carbohydrate may not have been appropriate and protein intakes may have been excessively high. Thus, in a proof-of-concept study we compared two relatively low-fat weight loss diets - one high in protein and the other high in fiber-rich, minimally processed cereals and legumes - to determine whether a relatively high protein diet has the potential to confer greater benefits. Methods Eighty-three overweight or obese women, 18-65 years, were randomized to either a moderately high protein (30% protein, 40% carbohydrate diet (HP or to a high fiber, relatively high carbohydrate (50% carbohydrate, > 35 g total dietary fiber, 20% protein diet (HFib for 8 weeks. Energy intakes were reduced by 2000 - 4000 kJ per day in order to achieve weight loss of between 0.5 and 1 kg per week. Results Participants on both diets lost weight (HP: -4.5 kg [95% confidence interval (CI:-3.7, -5.4 kg] and HFib: -3.3 kg [95% CI: -4.2, -2.4 kg], and reduced total body fat (HP: -4.0 kg [5% CI:-4.6, -3.4 kg] and HFib: -2.5 kg [95% CI: -3.5, -1.6 kg], and waist circumference (HP: -5.4 cm [95% CI: -6.3, -4.5 cm] and HFib: -4.7 cm [95% CI: -5.8, -3.6 cm], as well as total and LDL cholesterol, triglycerides, fasting plasma glucose and blood pressure. However participants on HP lost more body weight (-1.3 kg [95% CI: -2.5, -0.1 kg; p = 0.039] and total body fat (-1.3 kg [95% CI: -2.4, -0.1; p = 0.029]. Diastolic blood pressure decreased more on HP (-3.7 mm Hg [95% CI: -6.2, -1.1; p = 0.005]. Conclusions A realistic high protein weight-reducing diet was associated with greater fat loss and lower blood pressure when compared with a high carbohydrate, high fiber diet in high risk overweight and obese women.

  13. New waveguide shape for low loss and high uniformity y-branch optical splitter

    Science.gov (United States)

    Burtscher, Catalina; Seyringer, Dana; Lucki, Michal; Kohler, Linda

    2017-02-01

    The most common application of optical Y-splitters is their use in FTTx networks. It allows several customers to share the same physical medium, bringing high-speed networking, digital television and telephone services to residences using fiber-optic cables. The task of the optical splitters in such FTTH networks is to split one optical signal in many identical signals bringing for example the same TV signal in different households. Of course, the more buildings can be served by one optical splitter the lower are the installation costs. Therefore, the special attention is paid mainly to the design of high channel optical splitters presenting the serious challenge for the professional designers. In this paper a new Y-branch shape is proposed for 1×32 Y-branch splitter ensuring better splitting properties compared to the one recommended by ITU, in terms of their performance in transmission systems using wavelength division multiplexing.

  14. Time Is Money: The Decision Making of Smartphone High Users in Gain and Loss Intertemporal Choice

    OpenAIRE

    Tang, Zixuan; Zhang, Huijun; Yan, An; Qu, Chen

    2017-01-01

    Nowadays the smartphone plays an important role in our lives. While it brings us convenience and efficiency, its overuse can cause problems. Although a great number of studies have demonstrated that people affected by substance abuse, pathological gambling, and internet addiction disorder have lower self-control than average, scarcely any study has investigated the decision making of smartphone high users by using a behavioral paradigm. The present study employed an intertemporal task, the Sm...

  15. The measurement of power losses at high magnetic field densities or at small cross-section of test specimen using the averaging

    CERN Document Server

    Gorican, V; Hamler, A; Nakata, T

    2000-01-01

    It is difficult to achieve sufficient accuracy of power loss measurement at high magnetic field densities where the magnetic field strength gets more and more distorted, or in cases where the influence of noise increases (small specimen cross section). The influence of averaging on the accuracy of power loss measurement was studied on the cast amorphous magnetic material Metglas 2605-TCA. The results show that the accuracy of power loss measurements can be improved by using the averaging of data acquisition points.

  16. Mobility management for highly mobile users and vehicular networks in heterogeneous environments

    OpenAIRE

    Andersson, Karl; Åhlund, Christer; Gukhool, Balkrishna Sharma; Cherkaoui, Soumaya

    2008-01-01

      With the recent developments in wireless networks, different radio access technologies are used in different places depending on capacity in terms of throughput, cell size, scalability etc. In this context, mobile users, and in particular highly mobile users and vehicular networks, will see an increasing number and variety of wireless access points enabling Internet connectivity. Such a heterogeneous networking environment needs, however, an efficient mobility management scheme offering ...

  17. Metabolic processes sustaining the reviviscence of lichen Xanthoria elegans (Link) in high mountain environments.

    OpenAIRE

    Aubert, Serge; Juge, Christine; Boisson, Anne-Marie; Gout, Elisabeth; Bligny, Richard

    2007-01-01

    International audience; To survive in high mountain environments lichens must adapt themselves to alternating periods of desiccation and hydration. Respiration and photosynthesis of the foliaceous lichen, Xanthoria elegans, in the dehydrated state were below the threshold of CO2-detection by infrared gas analysis. Following hydration, respiration totally recovered within seconds and photosynthesis within minutes. In order to identify metabolic processes that may contribute to the quick and ef...

  18. Speech Intelligibility of Aircrew Mask Communication Configurations in High-Noise Environments

    Science.gov (United States)

    2017-09-28

    all test conditions. The JSAM SA, shown in Fig. 1, is a respirator that provides individual aircrew members with “above the shoulder ” head, eye...is unlimited. 4 Fig. 2 ICU and (inset) switch settings for 3 communication modes Communication headsets plug into the ICU and rest on top of the... rest in the ear canal under the JSAM SA hood. In high-noise environments, additional hearing protection is often desired and may take the form of foam

  19. Thermohydraulic modeling of very high temperature reactors in regimes with loss of coolant using CFD

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, Uebert G.; Dominguez, Dany S. [Universidade Estadual de Santa Cruz (UESC), Ilh´eus, BA (Brazil). Programa de P´os-Graduacao em Modelagem Computacional em Ciencia e Tecnologia; Mazaira, Leorlen Y.R.; Lira, Carlos A.B.O. [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Departamento de Energia Nuclear; Hernandez, Carlos R.G., E-mail: uebert.gmoreira@gmail.com, E-mail: dsdominguez@gmail.com, E-mail: leored1984@gmail.com, E-mail: cabol@ufpe.br, E-mail: cgh@instec.cu [Instituto Superior de Tecnologas y Ciencias Aplicadas (InSTEC), La Habana (Cuba)

    2017-07-01

    The nuclear energy is a good alternative to meet the continuous increase in world energy demand. In this perspective, VHTRs (Very High Temperature Reactors) are serious candidates for energy generation due to its inherently safe performance, low power density and high conversion efficiency. However, the viability of these reactors depends on an efficient safety system in the operation of nuclear plants. The HTR (High Temperature Reactor)-10 model, an experimental reactor of the pebble bed type, is used as a case study in this work to perform the thermohydraulic simulation. Due to the complex patterns flow that appear in the pebble bed reactor core, and advances in computational capacity, CFD (Computational Fluid Dynamics) techniques are used to simulate these reactors. A realistic approach is adopted to simulate the central annular column of the reactor core, which each pebble bed element is modeled in detail. As geometrical model of the fuel elements was selected the BCC (Body Centered Cubic) arrangement. Previous works indicate this arrangement as the configuration that obtain higher fuel temperatures inside the core. Parameters considered for reactor design are available in the technical report of benchmark issues by IAEA (TECDOC-1694). Among the results obtained, we obtained the temperature profiles with different mass flow rates for the coolant. In general, the temperature distributions calculated are consistent with phenomenological behaviour. Even without consider the reactivity changes to reduce the reactor power or other safety procedures, the maximum temperatures do not exceed the recommended limits for fuel elements. (author)

  20. The Association Between Supportive High School Environments and Depressive Symptoms and Suicidality Among Sexual Minority Students.

    Science.gov (United States)

    Denny, Simon; Lucassen, Mathijs F G; Stuart, Jaimee; Fleming, Theresa; Bullen, Pat; Peiris-John, Roshini; Rossen, Fiona V; Utter, Jennifer

    2016-01-01

    The purpose of this study was to determine if sexual minority students in supportive school environments experienced fewer depressive symptoms and lower rates of suicide ideation, plans and attempts ("suicidality") than sexual minority students in less supportive school environments. In 2007, a nationally representative sample (N = 9,056) of students from 96 high schools in New Zealand used Internet tablets to complete a health and well-being survey that included questions on sexual attractions, depressive symptoms, and suicidality. Students reported their experience of supportive environments at school and gay, lesbian, bisexual, and transgender (GLBT) bullying, and these items were aggregated to the school level. Teachers (n = 2,901) from participating schools completed questionnaires on aspects of school climate, which included how supportive their schools were toward sexual minority students. Multilevel models were used to estimate school effects on depressive symptoms and suicidality controlling for background characteristics of students. Sexual minority students were more likely to report higher levels of depressive symptoms and suicidality than their opposite-sex attracted peers (p school environments for GLBT students were associated with fewer depressive symptoms among male sexual minority students (p = .006) but not for female sexual minority students (p = .09). Likewise in schools where students reported a more supportive school environment, male sexual minority students reported fewer depressive symptoms (p = .006) and less suicidality (p schools where students reported less favorable school climates. These results suggest that schools play an important role in providing safe and supportive environments for male sexual minority students.

  1. naturally high temperature and high total alkalinity environment of the Red Sea

    KAUST Repository

    Roik, Anna Krystyna

    2018-02-28

    The coral structural framework is crucial for maintaining reef ecosystem function and services. Rising seawater temperatures impair the calcification capacity of reef-building organisms on a global scale, but in the Red Sea total alkalinity is naturally high and beneficial to reef growth. It is currently unknown how beneficial and detrimental factors affect the balance between calcification and erosion, and thereby overall reef growth, in the Red Sea. To provide estimates of present-day carbonate budgets and reef growth dynamics in the central Red Sea, we measured in situ net-accretion and net-erosion rates (Gnet) by deployment of limestone blocks to estimate census-based carbonate budgets (Gbudget) in four reef sites along a cross-shelf gradient (25 km). In addition, we assessed abiotic (i.e., temperature, inorganic nutrients, and carbonate system variables) and biotic (i.e., calcifier and bioeroder abundances) variables. Our data show that aragonite saturation states (Ω = 3.65–4.20) were in the upper range compared to the chemistry of other tropical reef sites. Further, Gnet and Gbudget encompassed positive (offshore) and negative (midshore-lagoon and exposed nearshore site) carbonate budgets. Notably, Gbudget maxima were lower compared to reef growth from undisturbed Indian Ocean reefs, but erosive forces for Red Sea reefs were not as strong as observed elsewhere. In line with this, a comparison with recent historical data from the northern Red Sea suggests that overall reef growth in the Red Sea has remained similar since 1995. When assessing reef sites across the shelf gradient, AT correlated well and positive with reef growth (ρ = 0.9), while temperature (ρ = −0.7), pH variation (ρ = −0.8), and pCO2 (ρ = −0.8) were weaker negative correlates. Noteworthy for this oligotrophic sea was the positive effect of PO43− (ρ = 0.7) on reef growth. In the best-fitting distance-based linear model, AT explained about 64 % of Gbudget. Interestingly

  2. Limits to the thermal tolerance of corals adapted to a highly fluctuating, naturally extreme temperature environment

    Science.gov (United States)

    Schoepf, Verena; Stat, Michael; Falter, James L.; McCulloch, Malcolm T.

    2015-12-01

    Naturally extreme temperature environments can provide important insights into the processes underlying coral thermal tolerance. We determined the bleaching resistance of Acropora aspera and Dipsastraea sp. from both intertidal and subtidal environments of the naturally extreme Kimberley region in northwest Australia. Here tides of up to 10 m can cause aerial exposure of corals and temperatures as high as 37 °C that fluctuate daily by up to 7 °C. Control corals were maintained at ambient nearshore temperatures which varied diurnally by 4-5 °C, while treatment corals were exposed to similar diurnal variations and heat stress corresponding to ~20 degree heating days. All corals hosted Symbiodinium clade C independent of treatment or origin. Detailed physiological measurements showed that these corals were nevertheless highly sensitive to daily average temperatures exceeding their maximum monthly mean of ~31 °C by 1 °C for only a few days. Generally, Acropora was much more susceptible to bleaching than Dipsastraea and experienced up to 75% mortality, whereas all Dipsastraea survived. Furthermore, subtidal corals, which originated from a more thermally stable environment compared to intertidal corals, were more susceptible to bleaching. This demonstrates that while highly fluctuating temperatures enhance coral resilience to thermal stress, they do not provide immunity to extreme heat stress events.

  3. Solar Arrays for Low-Irradiance Low-Temperature and High-Radiation Environments

    Science.gov (United States)

    Boca, Andreea (Principal Investigator); Stella, Paul; Kerestes, Christopher; Sharps, Paul

    2017-01-01

    This is the Base Period final report DRAFT for the JPL task 'Solar Arrays for Low-Irradiance Low-Temperature and High-Radiation Environments', under Task Plan 77-16518 TA # 21, for NASA's Extreme Environments Solar Power (EESP) project. This report covers the Base period of performance, 7/18/2016 through 5/2/2017.The goal of this project is to develop an ultra-high efficiency lightweight scalable solar array technology for low irradiance, low temperature and high-radiation (LILT/Rad) environments. The benefit this technology will bring to flight systems is a greater than 20 reduction in solar array surface area, and a six-fold reduction in solar array mass and volume. The EESP project objectives are summarized in the 'NRA Goal' column of Table 1. Throughout this report, low irradiance low temperature (LILT) refers to 5AU -125 C test conditions; beginning of life (BOL) refers to the cell state prior to radiation exposure; and end of life (EOL) refers to the test article condition after exposure to a radiation dose of 4e15 1MeV e(-)/cm(exp 2).

  4. Thin Film Sensors for Minimally-Intrusive Measurements in Harsh High Temperature Environment

    Science.gov (United States)

    Lei, Jih-Fen; Will, Herbert A.; Martin, Lisa C.

    1998-01-01

    Advanced thin film sensors are being developed to provide accurate surface temperature, heat flux and strain measurements for components used in hostile propulsion environments. These sensors are sputter deposited and microfabricated directly onto the test articles with no additional bonding agent. The thickness of the sensors is only a few micrometers which creates minimal disturbance of the gas flow over the test surface. Thus thin film sensors have the advantage over conventional wire- based sensors by providing minimally intrusive measurement and having a faster response. These thin film sensors are being developed for characterization of advanced materials and structures in hostile, high-temperature environments, and for validation of design codes. This paper presents the advances of three high temperature thin film sensor technologies developed at NASA Lewis Research Center: thermocouples, heat-flux gages and strain gages. The fabrication techniques of these thin film sensors which include physical vapor deposition, photolithography patterning and lead Wire attachment are described. Sensors demonstrations on a variety of engine materials, including superalloys, ceramics and advanced ceramic matrix composites, in several hostile, high-temperature test environments are presented. The advantages and limitations of thin film sensor technology are also discussed.

  5. State of the art and recommendations. Kangaroo mother care: application in a high-tech environment.

    Science.gov (United States)

    Nyqvist, K H; Anderson, G C; Bergman, N; Cattaneo, A; Charpak, N; Davanzo, R; Ewald, U; Ludington-Hoe, S; Mendoza, S; Pallás-Allonso, C; Peláez, J G; Sizun, J; Widström, A-M

    2010-06-01

    Since Kangaroo Mother Care (KMC) was developed in Colombia in the 1970s, two trends in clinical application emerged. In low income settings, the original KMC model is implemented. This consists of continuous (24 h/day, 7 days/week) and prolonged mother/parent-infant skin-to-skin contact; early discharge with the infant in the kangaroo position; (ideally) exclusive breastfeeding; and, adequate follow-up. In affluent settings, intermittent KMC with sessions of one or a few hours skin-to-skin contact for a limited period is common. As a result of the increasing evidence of the benefits of KMC for both infants and families in all intensive care settings, KMC in a high-tech environment was chosen as the topic for the first European Conference on KMC, and the clinical implementation of the KMC model in all types of settings was discussed at the 7th International Workshop on KMC. Kangaroo Mother Care protocols in high-tech Neonatal Intensive Care Units (NICU) should specify criteria for initiation, kangaroo position, transfer to/from KMC, transport in kangaroo position, kangaroo nutrition, parents' role, modification of the NICU environment, performance of care in KMC, and KMC in case of infant instability. Implementation of the original KMC method, with continuous skin-to-skin contact whenever possible, is recommended for application in high-tech environments, although scientific evaluation should continue.

  6. Early hearing loss detection in rheumatoid arthritis and primary Sjögren syndrome using extended high frequency audiometry.

    Science.gov (United States)

    Galarza-Delgado, Dionicio Angel; Villegas Gonzalez, Mario Jesus; Riega Torres, Janett; Soto-Galindo, German A; Mendoza Flores, Lidia; Treviño González, José Luis

    2018-02-01

    The aim of this study is to evaluate the hearing behavior of rheumatoid arthritis (RA) and primary Sjögren syndrome (PSS) patients and compare them with a healthy control group and with each other. A comparative cross-sectional study was performed with a group of 117 female RA patients, a group of 60 female PSS patients, and a 251 female healthy control group. Every subject underwent a series of studies including high-frequency audiometry, speech audiometry, and tympanometry. The high-frequency audiometry measured 250 to 16,000 Hz. The 117 patients with RA and the 60 with PSS were diagnosed according to American College of Rheumatology criteria / ACR 2010, and the validated classification of the American-European Consensus Group. Hearing loss was present in 36.8% of the RA group in 500-3000 Hz, 68.4% in 4000-8000 Hz, and 94.9% in 10,000-16,000 Hz. Hearing loss was present in 60% of the PSS group in 500-3000 Hz, 70% in 4000-8000 Hz, and 100% in 10,000-16,000 Hz. The hearing impairment prevalence of both groups was significantly different (p < 0.05) when compared with the healthy control group. We also compared the hearing thresholds between RA and PSS patients, finding a significant hearing threshold increase in 500-3000 Hz of the PSS group. This study consolidates the association between RA and PSS with hearing impairment. A deeper hearing loss was reported in PSS than in RA patients, demonstrating a greater auditory and speech recognition repercussion.

  7. Advanced Passivation Technology and Loss Factor Minimization for High Efficiency Solar Cells.

    Science.gov (United States)

    Park, Cheolmin; Balaji, Nagarajan; Jung, Sungwook; Choi, Jaewoo; Ju, Minkyu; Lee, Seunghwan; Kim, Jungmo; Bong, Sungjae; Chung, Sungyoun; Lee, Youn-Jung; Yi, Junsin

    2015-10-01

    High-efficiency Si solar cells have attracted great attention from researchers, scientists, photovoltaic (PV) industry engineers for the past few decades. With thin wafers, surface passivation becomes necessary to increase the solar cells efficiency by overcoming several induced effects due to associated crystal defects and impurities of c-Si. This paper discusses suitable passivation schemes and optimization techniques to achieve high efficiency at low cost. SiNx film was optimized with higher transmittance and reduced recombination for using as an effective antireflection and passivation layer to attain higher solar cell efficiencies. The higher band gap increased the transmittance with reduced defect states that persisted at 1.68 and 1.80 eV in SiNx films. The thermal stability of SiN (Si-rich)/SiN (N-rich) stacks was also studied. Si-rich SiN with a refractive index of 2.7 was used as a passivation layer and N-rich SiN with a refractive index of 2.1 was used for thermal stability. An implied Voc of 720 mV with a stable lifetime of 1.5 ms was obtained for the stack layer after firing. Si-N and Si-H bonding concentration was analyzed by FTIR for the correlation of thermally stable passivation mechanism. The passivation property of spin coated Al2O3 films was also investigated. An effective surface recombination velocity of 55 cm/s with a high density of negative fixed charges (Qf) on the order of 9 x 10(11) cm(-2) was detected in Al2O3 films.

  8. Effects of a high-protein ketogenic diet on hunger, appetite, and weight loss in obese men feeding ad libitum.

    Science.gov (United States)

    Johnstone, Alexandra M; Horgan, Graham W; Murison, Sandra D; Bremner, David M; Lobley, Gerald E

    2008-01-01

    Altering the macronutrient composition of the diet influences hunger and satiety. Studies have compared high- and low-protein diets, but there are few data on carbohydrate content and ketosis on motivation to eat and ad libitum intake. We aimed to compare the hunger, appetite, and weight-loss responses to a high-protein, low-carbohydrate [(LC) ketogenic] and those to a high-protein, medium-carbohydrate [(MC) nonketogenic] diet in obese men feeding ad libitum. Seventeen obese men were studied in a residential trial; food was provided daily. Subjects were offered 2 high-protein (30% of energy) ad libitum diets, each for a 4-wk period-an LC (4% carbohydrate) ketogenic diet and an MC (35% carbohydrate) diet-randomized in a crossover design. Body weight was measured daily, and ketosis was monitored by analysis of plasma and urine samples. Hunger was assessed by using a computerized visual analogue system. Ad libitum energy intakes were lower with the LC diet than with the MC diet [P=0.02; SE of the difference (SED): 0.27] at 7.25 and 7.95 MJ/d, respectively. Over the 4-wk period, hunger was significantly lower (P=0.014; SED: 1.76) and weight loss was significantly greater (P=0.006; SED: 0.62) with the LC diet (6.34 kg) than with the MC diet (4.35 kg). The LC diet induced ketosis with mean 3-hydroxybutyrate concentrations of 1.52 mmol/L in plasma (P=0.036 from baseline; SED: 0.62) and 2.99 mmol/L in urine (Pketogenic diets reduce hunger and lower food intake significantly more than do high-protein, medium-carbohydrate nonketogenic diets.

  9. Highly stable and low loss electro-optic polymer waveguides for high speed microring modulators using photodefinition

    OpenAIRE

    Balakrishnan, M.; Diemeer, Mart; Driessen, A.; Faccini, M.; Verboom, Willem; Reinhoudt, David; Leinse, Arne; Sidorin, Y.; Waechter, C.A.

    2006-01-01

    Different electro-optic polymer systems are analyzed with respect to their electro-optic activity, glass transition temperature (Tg) and photodefinable properties. The polymers tested are polysulfone (PS) and SU8. The electro-optic chromophore, tricyanovinylidenediphenylaminobenzene (TCVDPA), which was reported to have a high photochemical stability has been employed in the current work. Tert-butyl-TCVDPA, having bulky side groups, was synthesized and a doubling of the electro-optic coefficie...

  10. The loss of magnetism in FeS under high pressures

    Energy Technology Data Exchange (ETDEWEB)

    Ropka, Z. [Center for Solid State Physics, Krakow (Poland); Radwanski, R.J. [Center for Solid State Physics, Krakow (Poland); Institute of Physics, Pedagogical University, 30-084 Krakow (Poland)

    2003-03-01

    It is argued that the formation of the non-magnetic state of FeS in external pressures above 6.5 GPa is in agreement with the prediction of the many-electron crystal-field theory with the spin-orbit coupling incorporated, and is related to the change of sign of the off-octahedral trigonal distortion marked by the dramatic change of the c/a ratio from larger than 1.63 in the low-pressure magnetic state to smaller than 1.63 in the high-pressure non-magnetic state. (Abstract Copyright [2003], Wiley Periodicals, Inc.)

  11. High Levels of Canonical Wnt Signaling Lead to Loss of Stemness and Increased Differentiation in Hematopoietic Stem Cells

    Directory of Open Access Journals (Sweden)

    Farbod Famili

    2016-05-01

    Full Text Available Canonical Wnt signaling regulates the self-renewal of most if not all stem cell systems. In the blood system, the role of Wnt signaling has been the subject of much debate but there is consensus that high Wnt signals lead to loss of reconstituting capacity. To better understand this phenomenon, we have taken advantage of a series of hypomorphic mutant Apc alleles resulting in a broad range of Wnt dosages in hematopoietic stem cells (HSCs and performed whole-genome gene expression analyses. Gene expression profiling and functional studies show that HSCs with APC mutations lead to high Wnt levels, enhanced differentiation, and diminished proliferation but have no effect on apoptosis, collectively leading to loss of stemness. Thus, we provide mechanistic insight into the role of APC mutations and Wnt signaling in HSC biology. As Wnt signals are explored in various in vivo and ex vivo expansion protocols for HSCs, our findings also have clinical ramifications.

  12. Bromination of graphene: a new route to making high performance transparent conducting electrodes with low optical losses

    KAUST Repository

    Mansour, Ahmed

    2015-09-03

    The high optical transmittance, electrical conductivity, flexibility and chemical stability of graphene have triggered great interest in its application as a transparent conducting electrode material and as a potential replacement for indium doped tin oxide. However, currently available large scale production methods such as chemical vapor deposition produce polycrystalline graphene, and require additional transfer process which further introduces defects and impurities resulting in a significant increase in its sheet resistance. Doping of graphene with foreign atoms has been a popular route for reducing its sheet resistance which typically comes at a significant loss in optical transmission. Herein, we report the successful bromine doping of graphene resulting in air-stable transparent conducting electrodes with up to 80% reduction of sheet resistance reaching ~180 Ω/ at the cost of 2-3% loss of optical transmission in case of few layer graphene and 0.8% in case of single layer graphene. The remarkably low tradeoff in optical transparency leads to the highest enhancements in figure of merit reported thus far. Furthermore, our results show a controlled increase in the workfunction up to 0.3 eV with the bromine content. These results should help pave the way for further development of graphene as potentially a highly transparent substitute to other transparent conducting electrodes in optoelectronic devices.

  13. Detonation mode and frequency analysis under high loss conditions for stoichiometric propane-oxygen

    KAUST Repository

    Jackson, Scott

    2016-03-24

    The propagation characteristics of galloping detonations were quantified with a high-time-resolution velocity diagnostic. Combustion waves were initiated in 30-m lengths of 4.1-mm inner diameter transparent tubing filled with stoichiometric propane-oxygen mixtures. Chemiluminescence from the resulting waves was imaged to determine the luminous wave front position and velocity every 83.3 μ. As the mixture initial pressure was decreased from 20 to 7 kPa, the wave was observed to become increasingly unsteady and transition from steady detonation to a galloping detonation. While wave velocities averaged over the full tube length smoothly decreased with initial pressure down to half of the Chapman-Jouguet detonation velocity (DCJ) at the quenching limit, the actual propagation mechanism was seen to be a galloping wave with a cycle period of approximately 1.0 ms, corresponding to a cycle length of 1.3-2.0 m or 317-488 tube diameters depending on the average wave speed. The long test section length of 7300 tube diameters allowed observation of up to 20 galloping cycles, allowing for statistical analysis of the wave dynamics. In the galloping regime, a bimodal velocity distribution was observed with peaks centered near 0.4 DCJ and 0.95 DCJ. Decreasing initial pressure increasingly favored the low velocity mode. Galloping frequencies ranged from 0.8 to 1.0 kHz and were insensitive to initial mixture pressure. Wave deflagration-to-detonation transition and detonation failure trajectories were found to be repeatable in a given test and also across different initial mixture pressures. The temporal duration of wave dwell at the low and high velocity modes during galloping was also quantified. It was found that the mean wave dwell duration in the low velocity mode was a weak function of initial mixture pressure, while the mean dwell time in the high velocity mode depended exponentially on initial mixture pressure. Analysis of the velocity histories using dynamical systems ideas

  14. High-fiber diet promotes weight loss and affects maternal behavior in vervet monkeys.

    Science.gov (United States)

    Fairbanks, Lynn A; Blau, Karin; Jorgensen, Matthew J

    2010-03-01

    The dramatic increase in obesity in western societies has shifted the emphasis in nutrition research from the problems of undernutrition to the adverse consequences of being overweight. As with humans, Old World monkeys are at increased risk for type II diabetes and other chronic diseases when they gain excessive weight. To prevent overweight and obesity, promote animal health, and provide a more natural level of fiber in the diet, the standard commercial monkey chow diet at a vervet monkey breeding colony was changed to a higher fiber formulation in 2004. The new diet was also higher in protein and lower in carbohydrate and energy density than the standard diet. Because maternal behavior is known to be sensitive to differences in resource availability, data on weight and mother-infant interactions for 147 mothers with 279 infants born from 2000 through 2006 were assessed for effects of the diet change. The results showed that, even though food was provided ad libitum, the mean body weight of breeding females was 10% lower after the transition to the high-fiber diet. Behaviorally, mothers on the high-fiber diet were significantly more rejecting to their infants, and their infants had to play a greater role in maintaining ventral contact in the first few months of their lives. The effects of the diet change on maternal rejection were significantly related to the mother's body weight, with lower-weight mothers scoring higher in maternal rejection. These results demonstrate that maternal behavior is responsive to changes in maternal condition, and that beneficial changes in the diet may have unintended consequences on behavior. 2009 Wiley-Liss, Inc.

  15. Hearing loss

    Science.gov (United States)

    Decreased hearing; Deafness; Loss of hearing; Conductive hearing loss; Sensorineural hearing loss; Presbycusis ... Symptoms of hearing loss may include: Certain sounds seeming too loud Difficulty following conversations when two or more people are talking ...

  16. Effect of Chromium on Corrosion Behavior of P110 Steels in CO2-H2S Environment with High Pressure and High Temperature

    Science.gov (United States)

    Sun, Jianbo; Sun, Chong; Lin, Xueqiang; Cheng, Xiangkun; Liu, Huifeng

    2016-01-01

    The novel Cr-containing low alloy steels have exhibited good corrosion resistance in CO2 environment, mainly owing to the formation of Cr-enriched corrosion film. In order to evaluate whether it is applicable to the CO2 and H2S coexistence conditions, the corrosion behavior of low-chromium steels in CO2-H2S environment with high pressure and high temperature was investigated using weight loss measurement and surface characterization. The results showed that P110 steel suffered localized corrosion and both 3Cr-P110 and 5Cr-P110 steels exhibited general corrosion. However, the corrosion rate of 5Cr-P110 was the highest among them. The corrosion process of the steels was simultaneously governed by CO2 and H2S. The outer scales on the three steels mainly consisted of FeS1−x crystals, whereas the inner scales on Cr-containing steels comprised of amorphous FeS1−x, Cr(OH)3 and FeCO3, in contrast with the amorphous FeS1−x and FeCO3 mixture film of P110 steel. The more chromium the steel contains, the more chromium compounds the corrosion products contain. The addition of chromium in steels increases the uniformity of the Cr-enriched corrosion scales, eliminates the localized corrosion, but cannot decrease the general corrosion rates. The formation of FeS1−x may interfere with Cr-enriched corrosion scales and lowering the corrosion performance of 3Cr-P110 and 5Cr-P110 steels. PMID:28773328

  17. Effect of Chromium on Corrosion Behavior of P110 Steels in CO2-H2S Environment with High Pressure and High Temperature

    Directory of Open Access Journals (Sweden)

    Jianbo Sun

    2016-03-01

    Full Text Available The novel Cr-containing low alloy steels have exhibited good corrosion resistance in CO2 environment, mainly owing to the formation of Cr-enriched corrosion film. In order to evaluate whether it is applicable to the CO2 and H2S coexistence conditions, the corrosion behavior of low-chromium steels in CO2-H2S environment with high pressure and high temperature was investigated using weight loss measurement and surface characterization. The results showed that P110 steel suffered localized corrosion and both 3Cr-P110 and 5Cr-P110 steels exhibited general corrosion. However, the corrosion rate of 5Cr-P110 was the highest among them. The corrosion process of the steels was simultaneously governed by CO2 and H2S. The outer scales on the three steels mainly consisted of FeS1−x crystals, whereas the inner scales on Cr-containing steels comprised of amorphous FeS1−x, Cr(OH3 and FeCO3, in contrast with the amorphous FeS1−x and FeCO3 mixture film of P110 steel. The more chromium the steel contains, the more chromium compounds the corrosion products contain. The addition of chromium in steels increases the uniformity of the Cr-enriched corrosion scales, eliminates the localized corrosion, but cannot decrease the general corrosion rates. The formation of FeS1−x may interfere with Cr-enriched corrosion scales and lowering the corrosion performance of 3Cr-P110 and 5Cr-P110 steels.

  18. Analytical Switching Cycle Modeling of Bidirectional High Voltage Flyback Converter for Capacitive Load Considering Core Loss Effect

    DEFF Research Database (Denmark)

    Huang, Lina; Zhang, Zhe; Andersen, Michael A. E.

    2015-01-01

    With the advancement of material science, various smart materials with intrinsic capacitive property are emerging. The high voltage (HV) power electronics converters with bidirectional energy flow functionality for supplying the capacitive load are highly demanded. A switching cycle based...... of configuration and working principle. Considering the parasitic elements as well as the core loss effect, the converter is modeled with analytical formulas for one switching cycle. The comparison between the model based calculation results and prototype experiments based measurement results are used to validate...... analytical model of HV bidirectional converter driving capacitive load is beneficial in thoroughly understanding the operational behavior, investigating the energy efficiency and optimizing the design. In this paper, a HV bidirectional flyback converter for capacitive load is generally discussed in terms...

  19. A High Resolution/Accurate Mass (HRAM) Data-Dependent MS3 Neutral Loss Screening, Classification, and Relative Quantitation Methodology for Carbonyl Compounds in Saliva

    Science.gov (United States)

    Dator, Romel; Carrà, Andrea; Maertens, Laura; Guidolin, Valeria; Villalta, Peter W.; Balbo, Silvia

    2017-04-01

    Reactive carbonyl compounds (RCCs) are ubiquitous in the environment and are generated endogenously as a result of various physiological and pathological processes. These compounds can react with biological molecules inducing deleterious processes believed to be at the basis of their toxic effects. Several of these compounds are implicated in neurotoxic processes, aging disorders, and cancer. Therefore, a method characterizing exposures to these chemicals will provide insights into how they may influence overall health and contribute to disease pathogenesis. Here, we have developed a high resolution accurate mass (HRAM) screening strategy allowing simultaneous identification and relative quantitation of DNPH-derivatized carbonyls in human biological fluids. The screening strategy involves the diagnostic neutral loss of hydroxyl radical triggering MS3 fragmentation, which is only observed in positive ionization mode of DNPH-derivatized carbonyls. Unique fragmentation pathways were used to develop a classification scheme for characterizing known and unanticipated/unknown carbonyl compounds present in saliva. Furthermore, a relative quantitation strategy was implemented to assess variations in the levels of carbonyl compounds before and after exposure using deuterated d 3 -DNPH. This relative quantitation method was tested on human samples before and after exposure to specific amounts of alcohol. The nano-electrospray ionization (nano-ESI) in positive mode afforded excellent sensitivity with detection limits on-column in the high-attomole levels. To the best of our knowledge, this is the first report of a method using HRAM neutral loss screening of carbonyl compounds. In addition, the method allows simultaneous characterization and relative quantitation of DNPH-derivatized compounds using nano-ESI in positive mode.

  20. Prevalence of hearing loss among high risk newborns hospitalized in hospitals affiliated to Tehran University of Medical Sciences

    Directory of Open Access Journals (Sweden)

    Ali Zamani

    2010-04-01

    Full Text Available "n Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: American pediatric Association proposes to screen all neonates with Oto-Acoustic Emission (OAE. In developing countries, because of several limitations, health policy makers recommend to screen only in high risk patients. This study is performed with the aim to screen hearing loss in 950 high risk newborns hospitalized in hospitals affiliated to Tehran University using the OAE test."n"nMethods: A total of 950 neonates hospitalized in the Neonatal and NICU wards of Vali-e-Asr, Shariati, Medical Center and Bahrami Hospitals during the years 2004-2006 who showed at least one risk factor using TEOAE hearing test were enrolled into this cross-sectional descriptive analytical study and were diagnosed with mild deafness and total deafness. Blood exchange due to hyperbillirubinemia, septicemia, congenital heart disease, the fifth minute apgar scores below six, PROM more than six hours, epilepsia, need to NICU more than five hours, pneumonia and Oto-Toxic drugs were considered as risk factors. Data was past medical history, current disease, admission cause, sign & symptoms and complications of disease."n"nResults: Multivariate logistic regression and paired t-test showed that blood exchange, low birth weight and low

  1. Extremely high UV-C radiation resistant microorganisms from desert environments with different manganese concentrations.

    Science.gov (United States)

    Paulino-Lima, Ivan Glaucio; Fujishima, Kosuke; Navarrete, Jesica Urbina; Galante, Douglas; Rodrigues, Fabio; Azua-Bustos, Armando; Rothschild, Lynn Justine

    2016-10-01

    Desiccation resistance and a high intracellular Mn/Fe ratio contribute to ionizing radiation resistance of Deinococcus radiodurans. We hypothesized that this was a general phenomenon and thus developed a strategy to search for highly radiation-resistant organisms based on their natural environment. While desiccation is a typical feature of deserts, the correlation between radiation resistance and the intracellular Mn/Fe ratio of indigenous microorganisms or the Mn/Fe ratio of the environment, has not yet been described. UV-C radiation is highly damaging to biomolecules including DNA. It was used in this study as a selective tool because of its relevance to early life on earth, high altitude aerobiology and the search for life beyond Earth. Surface soil samples were collected from the Sonoran Desert, Arizona (USA), from the Atacama Desert in Chile and from a manganese mine in northern Argentina. Microbial isolates were selected after exposure to UV-C irradiation and growth. The isolates comprised 28 genera grouped within six phyla, which we ranked according to their resistance to UV-C irradiation. Survival curves were performed for the most resistant isolates and correlated with their intracellular Mn/Fe ratio, which was determined by ICP-MS. Five percent of the isolates were highly resistant, including one more resistant than D. radiodurans, a bacterium generally considered the most radiation-resistant organism, thus used as a model for radiation resistance studies. No correlation was observed between the occurrence of resistant microorganisms and the Mn/Fe ratio in the soil samples. However, all resistant isolates showed an intracellular Mn/Fe ratio much higher than the sensitive isolates. Our findings could represent a new front in efforts to harness mechanisms of UV-C radiation resistance from extreme environments. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Behavior, reproduction, and immunity of crated pregnant gilts: effects of high dietary fiber and rearing environment.

    Science.gov (United States)

    McGlone, J J; Fullwood, S D

    2001-06-01

    The objective of this study was to examine effects of increased gut fill and diverse developing environments on pregnant gilts' behavior and physiology. Gilts were cross-fostered at 1 d of age and transferred to either an indoor or outdoor production unit. Littermate gilts remained in their different environments during development and were moved into individual gestation crates in an indoor gestation unit. Of the 42 gilts, 19 were fed a control diet of fortified sorghum-soybean meal and 23 were fed the same diet with 25% beet pulp (high fiber). Control sows ate 2.0 kg/d and high-fiber sows ate 2.67 kg/d in a large pellet (thus resulting in approximately equal energy intake and differing total dietary intakes). Pregnant gilts had behavior and immune measures sampled at 30, 60, and 90 d of gestation. The day x diet interaction was significant (P = 0.01) for duration of standing: sows fed high-fiber diets stood less on d 30, but on d 60 and 90 they and the control sows stood for a similar duration. Sham chewing duration and frequency showed significant (P Gilts reared outdoors and fed high fiber increased sham chewing over gestation, whereas all other treatment groups decreased this behavior over time. Outdoor-reared gilts had greater (P gilts. White blood cell numbers were higher (P gilts fed high-fiber diets than for gilts fed the control diet. Immune (humoral and cellular systems) and reproductive measures (farrowing rate and litter size) and plasma cortisol concentrations were generally not influenced (P > 0.10) by diets and rearing environments, suggesting that in spite of significant changes in behavior and feed intake gilts' immune systems were not suppressed or enhanced. Behavioral data alone suggested that indoor-reared gilts showed fewer behavioral adaptations to the crates than outdoor-reared gilts. However, immune measures did not indicate that any treatments resulted in physiological effects indicative of stress.

  3. Effect of a high-protein diet on maintenance of blood pressure levels achieved after initial weight loss: the DiOGenes randomized study

    NARCIS (Netherlands)

    Engberink, M.F.; Geleijnse, J.M.; Bakker, S.J.L.; Larsen, T.

    2015-01-01

    Randomized trials have shown significant blood pressure (BP) reductions after increased protein compared with carbohydrate intake, but the effect on BP maintenance after initial weight loss is unclear. We examined the effect of a high-protein diet on the maintenance of reduced BP after weight loss

  4. High Speed Railway Environment Safety Evaluation Based on Measurement Attribute Recognition Model

    Directory of Open Access Journals (Sweden)

    Qizhou Hu

    2014-01-01

    Full Text Available In order to rationally evaluate the high speed railway operation safety level, the environmental safety evaluation index system of high speed railway should be well established by means of analyzing the impact mechanism of severe weather such as raining, thundering, lightning, earthquake, winding, and snowing. In addition to that, the attribute recognition will be identified to determine the similarity between samples and their corresponding attribute classes on the multidimensional space, which is on the basis of the Mahalanobis distance measurement function in terms of Mahalanobis distance with the characteristics of noncorrelation and nondimensionless influence. On top of the assumption, the high speed railway of China environment safety situation will be well elaborated by the suggested methods. The results from the detailed analysis show that the evaluation is basically matched up with the actual situation and could lay a scientific foundation for the high speed railway operation safety.

  5. High temperature ultrasonic sensor for fission gas characterization in MTR harsh environment

    Directory of Open Access Journals (Sweden)

    Gatsa O.

    2018-01-01

    In this paper, we present NBT thick film fabrication by screen printing, characterization of piezoelectric, dielectric properties and material parameters studies in dependence of temperature. Relatively high resistivity in the range of 1.1013 Ohm.cm for fabricated thick film is explained by Aurivillius structure in which a-and b-layers form perovskite structure between oxides of c-layer. Main results of this study are presented and discussed in terms of feasibility for an application to a new sensor device operating at high temperature level (400°. Piezoelectric parameters enhancement and loss reduction at elevated temperatures are envisaged to be optimized. Further sensor development and test in MTR are expected to be realized in the near future.

  6. Highly alloyed Ni-W substrates for low AC loss applications

    Science.gov (United States)

    Gaitzsch, Uwe; Hänisch, Jens; Hühne, Ruben; Rodig, Christian; Freudenberger, Jens; Holzapfel, Bernhard; Schultz, Ludwig

    2013-08-01

    Cube texture formation has been studied in Ni-W alloys with a W content of 9 at.% and above. These alloys show a low magnetization at 77 K and below, and are therefore excellent candidates for use as substrates of coated conductors in AC applications. The application of a modified deformation and annealing sequence leads to a highly textured surface of Ni9W and Ni9.5W tapes with cube texture fractions above 96%. YBCO (YBa2Cu3O7-δ) layers obtained on these substrates using a standard buffer architecture showed a critical current density exceeding 1.5 MA cm-2 at 77 K, similar to those for films on commercial Ni5W tapes. In contrast, only a weak cube texture was achieved in Ni10W tapes. The rolling texture of this alloy showed a significantly increased Goss component, which could not be reduced by applying intermediate annealing treatments. The influence of this texture on the cube texture formation will be discussed in detail.

  7. A High-Fidelity Virtual Environment for the Study of Paranoia

    Directory of Open Access Journals (Sweden)

    Matthew R. Broome

    2013-01-01

    Full Text Available Psychotic disorders carry social and economic costs for sufferers and society. Recent evidence highlights the risk posed by urban upbringing and social deprivation in the genesis of paranoia and psychosis. Evidence based psychological interventions are often not offered because of a lack of therapists. Virtual reality (VR environments have been used to treat mental health problems. VR may be a way of understanding the aetiological processes in psychosis and increasing psychotherapeutic resources for its treatment. We developed a high-fidelity virtual reality scenario of an urban street scene to test the hypothesis that virtual urban exposure is able to generate paranoia to a comparable or greater extent than scenarios using indoor scenes. Participants (n=32 entered the VR scenario for four minutes, after which time their degree of paranoid ideation was assessed. We demonstrated that the virtual reality scenario was able to elicit paranoia in a nonclinical, healthy group and that an urban scene was more likely to lead to higher levels of paranoia than a virtual indoor environment. We suggest that this study offers evidence to support the role of exposure to factors in the urban environment in the genesis and maintenance of psychotic experiences and symptoms. The realistic high-fidelity street scene scenario may offer a useful tool for therapists.

  8. A High-Fidelity Virtual Environment for the Study of Paranoia

    Science.gov (United States)

    Broome, Matthew R.; Zányi, Eva; Selmanovic, Elmedin; Czanner, Silvester; Birchwood, Max; Chalmers, Alan; Singh, Swaran P.

    2013-01-01

    Psychotic disorders carry social and economic costs for sufferers and society. Recent evidence highlights the risk posed by urban upbringing and social deprivation in the genesis of paranoia and psychosis. Evidence based psychological interventions are often not offered because of a lack of therapists. Virtual reality (VR) environments have been used to treat mental health problems. VR may be a way of understanding the aetiological processes in psychosis and increasing psychotherapeutic resources for its treatment. We developed a high-fidelity virtual reality scenario of an urban street scene to test the hypothesis that virtual urban exposure is able to generate paranoia to a comparable or greater extent than scenarios using indoor scenes. Participants (n = 32) entered the VR scenario for four minutes, after which time their degree of paranoid ideation was assessed. We demonstrated that the virtual reality scenario was able to elicit paranoia in a nonclinical, healthy group and that an urban scene was more likely to lead to higher levels of paranoia than a virtual indoor environment. We suggest that this study offers evidence to support the role of exposure to factors in the urban environment in the genesis and maintenance of psychotic experiences and symptoms. The realistic high-fidelity street scene scenario may offer a useful tool for therapists. PMID:24455255

  9. [Multi-center study on the treatment for intermediate and high-frequency sudden sensorineural hearing loss].

    Science.gov (United States)

    Wang, Ming-ming; Fan, Zhao-min; Luo, Jian-fen; Hou, Zhi-qiang; Ai, Yu; Wang, Hai-bo; Xu, Min; Zhu, Kang; Hou, Jin; Li, Wen-yan

    2013-05-01

    To analyze the therapeutic effect of treatment for intermediate and high-frequency sudden sensorineural hearing loss (SSNHL). A prospective clinical multicentre research was conducted using international standardized approach of clinical research. SSNHL Cases with intermediate and high-frequency hearing loss, that accepted no medication from onset of hearing loss within two weeks duration and ages ranged between 18 and 65, were collected. All patients were treated by one of four treatments plans chosen by unified random table. 141 patients with intermediate and high-frequency SSNHL were recruited in the research. Twenty subjects were treated with lidocaine, 21 cases with lidocaine and hormone, 40 cases with Ginaton, and 60 cases with Ginaton and hormone. 42 out of 141 (29.79%) patients were total recovery, 24 (17.02%)achieved excellent recovery, 27 (19.15%)achieved partial recovery, and 48 (34.04%) were ineffective. The total effective rate was 65.96%. In lidocaine group, the total effective rate was 55.00%, 66.67% in lidocaine and hormone group, 67.50% in Ginaton group, and 68.33% in Ginaton and hormone group. Considering the total effective rate, there was no statistical difference between four groups (P > 0.05). However, the recovery rate in Ginaton group was significant difference comparing with that in lidocaine group (P = 0.0496). 119 had concomitant symptom of tinnitus, and the tinnitus was improved in patients of 81.51%. With regard to total effective rate of tinnitus in four treatment groups, it was 57.89% (11/19) in lidocaine group, 100.00% (18/18) in lidocaine and hormone group, 88.57% (31/35) in Ginaton group, 78.72% (37/47) in Ginaton and hormone group. There was significant ascendancy in lidocaine and hormone group versus that in lidocaine group (P = 0.002) and Ginaton and hormone group (P = 0.029). And the difference between lidocaine and Ginaton groups was statistical significance (χ(2) = 6.705, P hearing has no significantly different between

  10. Visual field loss morphology in high- and normal-tension glaucoma.

    Science.gov (United States)

    Iester, Michele; De Feo, Fabio; Douglas, Gordon R

    2012-01-01

    Purpose. To determine whether the patterns of visual field damage between high-tension glaucoma (HTG) and normal-tension glaucoma (NTG) are equivalent. Methods. In this retrospective cross-sectional study, fifty-one NTG and 57 HTG patients were recruited. For each recruited patient only the left eye was chosen. Glaucomatous patients had abnormal visual fields and/or glaucomatous changes at the optic nerve head. They were classified as HTG or NTG on the basis of intraocular pressure (IOP) measurements. Patients' visual fields were analyzed by using Humphrey Field Analyzer (HFA), program 30-2, full threshold. The visual field sensitivity values and the pattern deviation map values of the 72 tested points were considered. Then a pointwise analysis and an area analysis, based on the Glaucoma Hemifield test criteria, were performed, and a comparison between the two subgroups was made by Student's t test. Results. Between NTG and HTG, no significant difference was found pointwise for almost all the visual field points, except for two locations. One was under the blind spot, and the other was in the inferior hemifield around the twenty-degree position. When area analysis was considered, three areas showed a significantly different sensitivity between HTG and NTG. Conclusions. These data suggested that there was no relevant difference in the pointwise analysis between NTG and HTG; however, when visual field areas were compared, no difference in paracentral areas was found between NTG and HTG, but superior nasal step and inferior and superior scotomata showed to be deeper in HTG than in NTG.

  11. Silver Nanowire/MnO2 Nanowire Hybrid Polymer Nanocomposites: Materials with High Dielectric Permittivity and Low Dielectric Loss.

    Science.gov (United States)

    Zeraati, Ali Shayesteh; Arjmand, Mohammad; Sundararaj, Uttandaraman

    2017-04-26

    This study reports the fabrication of hybrid nanocomposites based on silver nanowire/manganese dioxide nanowire/poly(methyl methacrylate) (AgNW/MnO2NW/PMMA), using a solution casting technique, with outstanding dielectric permittivity and low dielectric loss. AgNW was synthesized using the hard-template technique, and MnO2NW was synthesized employing a hydrothermal method. The prepared AgNW:MnO2NW (2.0:1.0 vol %) hybrid nanocomposite showed a high dielectric permittivity (64 at 8.2 GHz) and low dielectric loss (0.31 at 8.2 GHz), which are among the best reported values in the literature in the X-band frequency range (8.2-12.4 GHz). The superior dielectric properties of the hybrid nanocomposites were attributed to (i) dimensionality match between the nanofillers, which increased their synergy, (ii) better dispersion state of AgNW in the presence of MnO2NW, (iii) positioning of ferroelectric MnO2NW in between AgNWs, which increased the dielectric permittivity of nanodielectrics, thereby increasing dielectric permittivity of the hybrid nanocomposites, (iv) barrier role of MnO2NW, i.e., cutting off the contact spots of AgNWs and leading to lower dielectric loss, and (v) AgNW aligned structure, which increased the effective surface area of AgNWs, as nanoelectrodes. Comparison of the dielectric properties of the developed hybrid nanocomposites with the literature highlights their great potential for flexible capacitors.

  12. The importance of a high-performance work environment in hospitals.

    Science.gov (United States)

    Weinberg, Dana Beth; Avgar, Ariel Chanan; Sugrue, Noreen M; Cooney-Miner, Dianne

    2013-02-01

    To examine the benefits of a high-performance work environment (HPWE) for employees, patients, and hospitals. Forty-five adult, medical-surgical units in nine hospitals in upstate New York. Cross-sectional study. Surveys were collected from 1,527 unit-based hospital providers (68.5 percent response rate). Hospitals provided unit turnover and patient data (16,459 discharge records and 2,920 patient surveys). HPWE, as perceived by multiple occupational groups on a unit, is significantly associated with desirable work processes, retention indicators, and care quality. Our findings underscore the potential benefits for providers, patients, and health care organizations of designing work environments that value and support a broad range of employees as having essential contributions to make to the care process and their organizations. © Health Research and Educational Trust.

  13. Operational characterisation of requirements and early validation environment for high demanding space systems

    Science.gov (United States)

    Barro, E.; Delbufalo, A.; Rossi, F.

    1993-01-01

    The definition of some modern high demanding space systems requires a different approach to system definition and design from that adopted for traditional missions. System functionality is strongly coupled to the operational analysis, aimed at characterizing the dynamic interactions of the flight element with its surrounding environment and its ground control segment. Unambiguous functional, operational and performance requirements are to be defined for the system, thus improving also the successive development stages. This paper proposes a Petri Nets based methodology and two related prototype applications (to ARISTOTELES orbit control and to Hermes telemetry generation) for the operational analysis of space systems through the dynamic modeling of their functions and a related computer aided environment (ISIDE) able to make the dynamic model work, thus enabling an early validation of the system functional representation, and to provide a structured system requirements data base, which is the shared knowledge base interconnecting static and dynamic applications, fully traceable with the models and interfaceable with the external world.

  14. An empirical analysis of the radio propagation characteristics in high-speed railway environment

    Science.gov (United States)

    Hu, Guoqing; Ma, Guangjin; Li, Chunlai; Xu, Yongchi; He, Jin; Yu, Ying; He, Yandong

    2017-09-01

    For a wireless mobile network, a profile of radio propagation characteristics is the key to study any wireless techniques, especially in High-Speed Railway (HSR) environment. Unfortunately, such a profile is not available so far, which leads manifold challenges to wireless study for HSR scenarios. In this paper, we focus on this topic, and try to obtain this profile in various kinds of HSR scenarios based on previous field tests in China. Our study reveals that the Line-Of-Sight (LOS) propagation path plays a predominant role in the HSR scenarios, which can suppress the shadow fading. Finally, we find out that each kind of small-scale fading effects has a unique profile on different wireless mobile systems for HSR scenarios. As a result, this study presents a theoretical guidance for studying any wireless techniques in HSR environment, e.g., cell handover for HSR.

  15. Development and Performance Verification of Fiber Optic Temperature Sensors in High Temperature Engine Environments

    Science.gov (United States)

    Adamovsky, Grigory; Mackey, Jeffrey R.; Kren, Lawrence A.; Floyd, Bertram M.; Elam, Kristie A.; Martinez, Martel

    2014-01-01

    A High Temperature Fiber Optic Sensor (HTFOS) has been developed at NASA Glenn Research Center for aircraft engine applications. After fabrication and preliminary in-house performance evaluation, the HTFOS was tested in an engine environment at NASA Armstrong Flight Research Center. The engine tests enabled the performance of the HTFOS in real engine environments to be evaluated along with the ability of the sensor to respond to changes in the engine's operating condition. Data were collected prior, during, and after each test in order to observe the change in temperature from ambient to each of the various test point levels. An adequate amount of data was collected and analyzed to satisfy the research team that HTFOS operates properly while the engine was running. Temperature measurements made by HTFOS while the engine was running agreed with those anticipated.

  16. Hypersonic Engine Leading Edge Experiments in a High Heat Flux, Supersonic Flow Environment

    Science.gov (United States)

    Gladden, Herbert J.; Melis, Matthew E.

    1994-01-01

    A major concern in advancing the state-of-the-art technologies for hypersonic vehicles is the development of an aeropropulsion system capable of withstanding the sustained high thermal loads expected during hypersonic flight. Three aerothermal load related concerns are the boundary layer transition from laminar to turbulent flow, articulating panel seals in high temperature environments, and strut (or cowl) leading edges with shock-on-shock interactions. A multidisciplinary approach is required to address these technical concerns. A hydrogen/oxygen rocket engine heat source has been developed at the NASA Lewis Research Center as one element in a series of facilities at national laboratories designed to experimentally evaluate the heat transfer and structural response of the strut (or cowl) leading edge. A recent experimental program conducted in this facility is discussed and related to cooling technology capability. The specific objective of the experiment discussed is to evaluate the erosion and oxidation characteristics of a coating on a cowl leading edge (or strut leading edge) in a supersonic, high heat flux environment. Heat transfer analyses of a similar leading edge concept cooled with gaseous hydrogen is included to demonstrate the complexity of the problem resulting from plastic deformation of the structures. Macro-photographic data from a coated leading edge model show progressive degradation over several thermal cycles at aerothermal conditions representative of high Mach number flight.

  17. An Evolutionary Method for Financial Forecasting in Microscopic High-Speed Trading Environment.

    Science.gov (United States)

    Huang, Chien-Feng; Li, Hsu-Chih

    2017-01-01

    The advancement of information technology in financial applications nowadays have led to fast market-driven events that prompt flash decision-making and actions issued by computer algorithms. As a result, today's markets experience intense activity in the highly dynamic environment where trading systems respond to others at a much faster pace than before. This new breed of technology involves the implementation of high-speed trading strategies which generate significant portion of activity in the financial markets and present researchers with a wealth of information not available in traditional low-speed trading environments. In this study, we aim at developing feasible computational intelligence methodologies, particularly genetic algorithms (GA), to shed light on high-speed trading research using price data of stocks on the microscopic level. Our empirical results show that the proposed GA-based system is able to improve the accuracy of the prediction significantly for price movement, and we expect this GA-based methodology to advance the current state of research for high-speed trading and other relevant financial applications.

  18. Effect of high ambient temperature on behavior of sheep under semi-arid tropical environment

    Science.gov (United States)

    De, Kalyan; Kumar, Davendra; Saxena, Vijay Kumar; Thirumurugan, Palanisamy; Naqvi, Syed Mohammed Khursheed

    2017-07-01

    High environmental temperature is a major constraint in sheep production under semi-arid tropical environment. Behavior is the earliest indicator of animal's adaptation and responses to the environmental alteration. Therefore, the objective of this study was to assess the effects of high ambient temperature on the behavior of sheep under a semi-arid tropical environment. The experiment was conducted for 6 weeks on 16 Malpura cross (Garole × Malpura × Malpura (GMM)) rams. The rams were divided equally into two groups, designated as C and T. The rams of C were kept in comfortable environmental conditions served as control. The rams of T were exposed to a different temperature at different hours of the day in a climatic chamber, to simulate a high environmental temperature of summer in semi-arid tropic. The behavioral observations were taken by direct instantaneous observation at 15-min intervals for each animal individually. The feeding, ruminating, standing, and lying behaviors were recorded twice a week from morning (0800 hours) to afternoon (1700 hours) for 6 weeks. Exposure of rams to high temperature (T) significantly ( P animals of T spent significantly ( P behavior of sheep which is directed to circumvent the effect of the stressor.

  19. Monocyte chemotactic protein-1 deficiency attenuates and high-fat diet exacerbates bone loss in mice with Lewis lung carcinoma.

    Science.gov (United States)

    Yan, Lin; Nielsen, Forrest H; Sundaram, Sneha; Cao, Jay

    2017-04-04

    Bone loss occurs in obesity and cancer-associated complications including wasting. This study determined whether a high-fat diet and a deficiency in monocyte chemotactic protein-1 (MCP-1) altered bone structural defects in male C57BL/6 mice with Lewis lung carcinoma (LLC) metastases in lungs. Compared to non-tumor-bearing mice, LLC reduced bone volume fraction, connectivity density, trabecular number, trabecular thickness and bone mineral density and increased trabecular separation in femurs. Similar changes occurred in vertebrae. The high-fat diet compared to the AIN93G diet exacerbated LLC-induced detrimental structural changes; the exacerbation was greater in femurs than in vertebrae. Mice deficient in MCP-1 compared to wild-type mice exhibited increases in bone volume fraction, connectivity density, trabecular number and decreases in trabecular separation in both femurs and vertebrae, and increases in trabecular thickness and bone mineral density and a decrease in structure model index in vertebrae. Lewis lung carcinoma significantly decreased osteocalcin but increased tartrate-resistant acid phosphatase 5b (TRAP 5b) in plasma. In LLC-bearing mice, the high-fat diet increased and MCP-1 deficiency decreased plasma TRAP 5b; neither the high-fat diet nor MCP-1 deficiency resulted in significant changes in plasma concentration of osteocalcin. In conclusion, pulmonary metastasis of LLC is accompanied by detrimental bone structural changes; MCP-1 deficiency attenuates and high-fat diet exacerbates the metastasis-associated bone wasting.

  20. Evaporative loss from irrigated interrows in a highly advective semi-arid agricultural area

    Science.gov (United States)

    Agam, Nurit; Evett, Steven R.; Tolk, Judy A.; Kustas, William P.; Colaizzi, Paul D.; Alfieri, Joseph G.; McKee, Lynn G.; Copeland, Karen S.; Howell, Terry A.; Chávez, Jose L.

    2012-12-01

    Agricultural productivity has increased in the Texas High Plains at the cost of declining water tables, putting at risk the sustainability of the Ogallala Aquifer as a principal source of water for irrigated agriculture. This has led area producers to seek alternative practices that can increase water use efficiency (WUE) through more careful management of water. One potential way of improving WUE is by reducing soil evaporation (E), thus reducing overall evapotranspiration (ET). Before searching for ways to reduce E, it is first important to quantify E and understand the factors that determine its magnitude. The objectives of this study were (1) to quantify E throughout part of the growing season for irrigated cotton in a strongly advective semi-arid region; (2) to study the effects of LAI, days after irrigation, and measurement location within the row on the E/ET fraction; and (3) to study the ability of microlysimeter (ML) measures of E combined with sap flow gage measures of transpiration (T) to accurately estimate ET when compared with weighing lysimeter ET data and to assess the E/T ratio. The research was conducted in an irrigated cotton field at the Conservation & Production Research Laboratory of the USDA-ARS, Bushland, TX. ET was measured by a large weighing lysimeter, and E was measured by 10 microlysimeters that were deployed in two sets of 5 across the interrow. In addition, 10 heat balance sap flow gages were used to determine T. A moderately good agreement was found between the sum E + T and ET (SE = 1 mm or ˜10% of ET). It was found that E may account for >50% of ET during early stages of the growing season (LAI < 0.2), significantly decreasing with increase in LAI to values near 20% at peak LAI of three. Measurement location within the north-south interrows had a distinct effect on the diurnal pattern of E, with a shift in time of peak E from west to east, a pattern that was governed by the solar radiation reaching the soil surface. However, total

  1. Near-highway aerosol and gas-phase measurements in a high-diesel environment

    Science.gov (United States)

    DeWitt, H. L.; Hellebust, S.; Temime-Roussel, B.; Ravier, S.; Polo, L.; Jacob, V.; Buisson, C.; Charron, A.; André, M.; Pasquier, A.; Besombes, J. L.; Jaffrezo, J. L.; Wortham, H.; Marchand, N.

    2015-04-01

    Diesel-powered passenger cars currently outnumber gasoline-powered cars in many countries, particularly in Europe. In France, diesel cars represented 61% of light duty vehicles in 2011 and this percentage is still increasing (French Environment and Energy Management Agency, ADEME). As part of the September 2011 joint PM-DRIVE (Particulate Matter - DiRect and Indirect on-road Vehicular Emissions) and MOCOPO (Measuring and mOdeling traffic COngestion and POllution) field campaign, the concentration and high-resolution chemical composition of aerosols and volatile organic carbon species were measured adjacent to a major urban highway south of Grenoble, France. Alongside these atmospheric measurements, detailed traffic data were collected from nearby traffic cameras and loop detectors, which allowed the vehicle type, traffic concentration, and traffic speed to be quantified. Six aerosol age and source profiles were resolved using the positive matrix factorization model on real-time high-resolution aerosol mass spectra. These six aerosol source/age categories included a hydrocarbon-like organic aerosol (HOA) commonly associated with primary vehicular emissions, a nitrogen-containing aerosol with a diurnal pattern similar to that of HOA, oxidized organic aerosol (OOA), and biomass burning aerosol. While quantitatively separating the influence of diesel from that of gasoline proved impossible, a low HOA : black carbon ratio, similar to that measured in other high-diesel environments, and high levels of NOx, also indicative of diesel emissions, were observed. Although the measurement site was located next to a large source of primary emissions, which are typically found to have low oxygen incorporation, OOA was found to comprise the majority of the measured organic aerosol, and isotopic analysis showed that the measured OOA contained mainly modern carbon, not fossil-derived carbon. Thus, even in this heavily vehicular-emission-impacted environment, photochemical processes

  2. Impact of Maine's statewide nutrition policy on high school food environments.

    Science.gov (United States)

    Whatley Blum, Janet E; Beaudoin, Christina M; O'Brien, Liam M; Polacsek, Michele; Harris, David E; O'Rourke, Karen A

    2011-01-01

    We assessed the effect on the food environments of public high schools of Maine's statewide nutrition policy (Chapter 51), which banned "foods of minimal nutritional value" (FMNV) in public high schools that participated in federally funded meal programs. We documented allowable exceptions to the policy and describe the school food environments. We mailed surveys to 89 high school food-service directors to assess availability pre-Chapter 51 and post-Chapter 51 of soda, other sugar-sweetened beverages, and junk food. Frequency data were tabulated pre-Chapter 51 and post-Chapter 51, and Fisher exact test was used to assess significance in changes. We conducted food and beverage inventories at 11 high schools. The survey return rate was 61% (N = 54). Availability of soda in student vending significantly decreased pre-Chapter 51 versus post-Chapter 51 (P = .04). No significant changes were found for other sugar-sweetened beverages and junk food. Exceptions to Chapter 51 were permitted to staff (67%), to the public (86%), and in career and technical education programs (31%). Inventories in a subset of schools found no availability of soda for students, whereas other sugar-sweetened beverages and junk food were widely available in à la carte, vending machines, and school stores. Candy, considered a FMNV, was freely available. Soda advertisement on school grounds was common. Student vending choices improved after the implementation of Chapter 51; however, use of FMNV as the policy standard may be limiting, as availability of other sugar-sweetened beverages and junk food was pervasive. School environments were not necessarily supportive of the policy, as advertisement of soda was common and some FMNV were available. Furthermore, local exceptions to Chapter 51 likely reduced the overall effect of the policy.

  3. Computational Transport Modeling of High-Energy Neutrons Found in the Space Environment

    Science.gov (United States)

    Cox, Brad; Theriot, Corey A.; Rohde, Larry H.; Wu, Honglu

    2012-01-01

    The high charge and high energy (HZE) particle radiation environment in space interacts with spacecraft materials and the human body to create a population of neutrons encompassing a broad kinetic energy spectrum. As an HZE ion penetrates matter, there is an increasing chance of fragmentation as penetration depth increases. When an ion fragments, secondary neutrons are released with velocities up to that of the primary ion, giving some neutrons very long penetration ranges. These secondary neutrons have a high relative biological effectiveness, are difficult to effectively shield, and can cause more biological damage than the primary ions in some scenarios. Ground-based irradiation experiments that simulate the space radiation environment must account for this spectrum of neutrons. Using the Particle and Heavy Ion Transport Code System (PHITS), it is possible to simulate a neutron environment that is characteristic of that found in spaceflight. Considering neutron dosimetry, the focus lies on the broad spectrum of recoil protons that are produced in biological targets. In a biological target, dose at a certain penetration depth is primarily dependent upon recoil proton tracks. The PHITS code can be used to simulate a broad-energy neutron spectrum traversing biological targets, and it account for the recoil particle population. This project focuses on modeling a neutron beamline irradiation scenario for determining dose at increasing depth in water targets. Energy-deposition events and particle fluence can be simulated by establishing cross-sectional scoring routines at different depths in a target. This type of model is useful for correlating theoretical data with actual beamline radiobiology experiments. Other work exposed human fibroblast cells to a high-energy neutron source to study micronuclei induction in cells at increasing depth behind water shielding. Those findings provide supporting data describing dose vs. depth across a water-equivalent medium. This

  4. Perceived neighborhood environment and physical activity among high school students from Curitiba, Brazil

    Directory of Open Access Journals (Sweden)

    Adalberto Aparecido dos Santos Lopes

    2014-12-01

    Full Text Available OBJECTIVE: To analyze the association between perceived neighborhood environment and physical activity (PA in high school students from Curitiba (PR, Brazil. METHODS: A sample of 1,611 high school students from public schools was surveyed. The PA was assessed through questions, engaged for at least 20 minutes or 60 minutes. Perceptions on neighborhood environment were assessed through ten questions about neighborhood characteristics. Gender, age and number of cars in the household were self-reported and used as confounding variables. Absolute and relative frequencies were used in the sample, and associations were tested through adjusted logistic regressions for the confounding variables and stratified by gender (p < 0.05. RESULTS: The adjusted analyses showed that the variables "interesting things" among girls (OR = 1.77; 95%CI 1.05 - 2.96 and "there are places I like" (OR = 2.18; 95%CI 1.33 - 3.58 and "I see people my age", among boys, were associated with PA of at least 20 minutes/day once a week. Additionally, among boys, "I see people my age" was associated with 60-minute (OR = 1.68; 95%CI 1.15 - 2.45. Perceiving the neighborhood environment as "very good" was associated with higher chances of taking up PA among girls (OR = 1.92; 95%CI 1.15 - 3.22 and boys (OR = 3.13; 95%CI 1.97 - 4.97. CONCLUSION: A positive perception of the environment was associated to PA practice among boys and girls in this sample. The results suggest that some environmental characteristics which make neighborhoods more attractive could be related to PA among adolescents.

  5. High fat diet attenuates hyperglycemia, body composition changes, and bone loss in male streptozotocin-induced type 1 diabetic mice.

    Science.gov (United States)

    Carvalho, Adriana Lelis; DeMambro, Victoria E; Guntur, Anyonya R; Le, Phuong; Nagano, Kenichi; Baron, Roland; de Paula, Francisco José Albuquerque; Motyl, Katherine J

    2018-02-01

    There is a growing and alarming prevalence of obesity and the metabolic syndrome in type I diabetic patients (T1DM), particularly in adolescence. In general, low bone mass, higher fracture risk, and increased marrow adipose tissue (MAT) are features of diabetic osteopathy in insulin-deficient subjects. On the other hand, type 2 diabetes (T2DM) is associated with normal or high bone mass, a greater risk of peripheral fractures, and no change in MAT. Therefore, we sought to determine the effect of weight gain on bone turnover in insulin-deficient mice. We evaluated the impact of a 6-week high-fat (HFD) rich in medium chain fatty acids or low-fat diet (LFD) on bone mass and MAT in a streptozotocin (STZ)-induced model using male C57BL/6J mice at 8 weeks of age. Dietary intervention was initiated after diabetes confirmation. At the endpoint, lower non-fasting glucose levels were observed in diabetic mice fed with high fat diet compared to diabetic mice fed the low fat diet (STZ-LFD). Compared to euglycemic controls, the STZ-LFD had marked polydipsia and polyphagia, as well as reduced lean mass, fat mass, and bone parameters. Interestingly, STZ-HFD mice had higher bone mass, namely less cortical bone loss and more trabecular bone than STZ-LFD. Thus, we found that a HFD, rich in medium chain fatty acids, protects against bone loss in a T1DM mouse model. Whether this may also translate to T1DM patients who are overweight or obese in respect to maintenance of bone mass remains to be determined through longitudinal studies. © 2017 Wiley Periodicals, Inc.

  6. High-resolution Whole-Genome Analysis of Skull Base Chordomas Implicates FHIT Loss in Chordoma Pathogenesis

    Directory of Open Access Journals (Sweden)

    Roberto Jose Diaz

    2012-09-01

    Full Text Available Chordoma is a rare tumor arising in the sacrum, clivus, or vertebrae. It is often not completely resectable and shows a high incidence of recurrence and progression with shortened patient survival and impaired quality of life. Chemotherapeutic options are limited to investigational therapies at present. Therefore, adjuvant therapy for control of tumor recurrence and progression is of great interest, especially in skull base lesions where complete tumor resection is often not possible because of the proximity of cranial nerves. To understand the extent of genetic instability and associated chromosomal and gene losses or gains in skull base chordoma, we undertook whole-genome single-nucleotide polymorphism microarray analysis of flash frozen surgical chordoma specimens, 21 from the clivus and 1 from C1 to C2 vertebrae. We confirm the presence of a deletion at 9p involving CDKN2A, CDKN2B, and MTAP but at a much lower rate (22% than previously reported for sacral chordoma. At a similar frequency (21%, we found aneuploidy of chromosome 3. Tissue microarray immunohistochemistry demonstrated absent or reduced fragile histidine triad (FHIT protein expression in 98% of sacral chordomas and 67%of skull base chordomas. Our data suggest that chromosome 3 aneuploidy and epigenetic regulation of FHIT contribute to loss of the FHIT tumor suppressor in chordoma. The finding that FHIT is lost in a majority of chordomas provides new insight into chordoma pathogenesis and points to a potential new therapeutic target for this challenging neoplasm.

  7. Bromination of Graphene: A New Route to Making High Performance Transparent Conducting Electrodes with Low Optical Losses

    KAUST Repository

    Mansour, Ahmed

    2015-07-22

    The unique optical and electrical properties of graphene have triggered great interest in its application as a transparent conducting electrode material and significant effort has been invested in achieving high conductivity while maintaining transparency. Doping of graphene has been a popular route for reducing its sheet resistance, but this has typically come at a significant cost in optical transmission. We demonstrate doping of few layers graphene with bromine as a means of enhancing the conductivity via intercalation without major optical losses. Our results demonstrate the encapsulation of bromine leads to air-stable transparent conducting electrodes with five-fold improvement of sheet resistance reaching at the cost of only 2-3% loss of optical transmission. The remarkably low tradeoff in optical transparency leads to the highest enhancements in the figure of merit reported thus far for FLG. Furthermore, we tune the workfunction by up to 0.3 eV by tuning the bromine content. These results should help pave the way for further development of graphene as a potential substitute to transparent conducting polymers and metal oxides used in optoelectronics, photovoltaics and beyond.

  8. Live cell imaging of mitochondria following targeted irradiation in situ reveals rapid and highly localized loss of membrane potential.

    Science.gov (United States)

    Walsh, Dietrich W M; Siebenwirth, Christian; Greubel, Christoph; Ilicic, Katarina; Reindl, Judith; Girst, Stefanie; Muggiolu, Giovanna; Simon, Marina; Barberet, Philippe; Seznec, Hervé; Zischka, Hans; Multhoff, Gabriele; Schmid, Thomas E; Dollinger, Guenther

    2017-04-25

    The reliance of all cell types on the mitochondrial function for survival makes mitochondria an interesting target when trying to understand their role in the cellular response to ionizing radiation. By harnessing highly focused carbon ions and protons using microbeams, we have performed in situ live cell imaging of the targeted irradiation of individual mitochondria stained with Tetramethyl rhodamine ethyl ester (TMRE), a cationic fluorophore which accumulates electrophoretically in polarized mitochondria. Targeted irradiation with both carbon ions and protons down to beam spots of <1 μm induced a near instant loss of mitochondrial TMRE fluorescence signal in the targeted area. The loss of TMRE after targeted irradiation represents a radiation induced change in mitochondrial membrane potential. This is the first time such mitochondrial responses have been documented in situ after targeted microbeam irradiation. The methods developed and the results obtained have the ability to shed new light on not just mitochondria's response to radiation but to further elucidate a putative mechanism of radiation induced depolarization and mitochondrial response.

  9. A simple structure of all circular-air-holes photonic crystal fiber for achieving high birefringence and low confinement loss

    Energy Technology Data Exchange (ETDEWEB)

    Chou Chau, Yuan-Fong, E-mail: chou.fong@ubd.edu.bn; Lim, Chee Ming; Yoong, Voo Nyuk; Syafi' ie Idris, Muhammad Nur [Centre for Advanced Material and Energy Sciences, Universiti Brunei Darussalam, Tungku Link, Gadong BE1410, Brunei (Brunei Darussalam)

    2015-12-28

    We propose a simple structure of photonic crystal fibers (PCFs) with high birefringence and low confinement loss based on one rectangular centric ring of smaller circular air holes (CAHs) in the fiber core, and three rings of larger CAHs in the fiber cladding. This simple geometry (using all CAHs with two different air hole sizes) is capable of achieving a flexible control of the birefringence, B = 5.501 × 10{sup −3}, and ultra-low confinement loss, 7.30 × 10{sup −5 }dB/km, at an excitation wavelength of λ = 1550 nm. The birefringence value is ∼5.0 times greater than that obtained for conventional CAH PCF. This simple structure has the added advantage from the view point of easy fabrication, robustness, and cost. A full-vector finite element method combined with anisotropic perfectly matched layers was used to analyze the various fiber structures. We have analyzed four cases of CAH PCFs, focusing on the core asymmetry design as opposed to the conventional approach of CAHs or elliptical air holes on the cladding and core. The robustness against manufacturing inaccuracies of the proposed structure has also been further investigated in this work.

  10. A.C. loss of the high-Tc superconducting cable conductor; Koon chodendo keburu dotai no koryu sonshitsu

    Energy Technology Data Exchange (ETDEWEB)

    Kume, A.; Futaki, N.; Ono, K.; Sadakata, N.; Saito, T. [Fujikura Ltd., Tokyo (Japan); Hasegawa, T. [Showa Electric Wire and Cable Co., Ltd., Kanagawa (Japan); Nagaya, S. [Chubu Electric Power Co., Ltd., Aichi (Japan)

    1999-06-07

    High-temperature superconducting cable used in the liquid nitrogen circulation cooling was expected in the electric power field, because of an attempt to compact the cable size and possibly reduce the power transmission loss. In the multilayer spiral conductor laminated by which Bi-2223 phase silver sheath tape were spirally wound and insulated between layers, the drift problem that current distribution concentrated in the outer layer occurred, because the inductance of the internal layer was higher than that of the outer layer in the alternating current. In this study, for a purpose of attempting the drift countermeasure and reduction of AC loss, the transposition yarn twist segment was composed of Bi-2223 phase silver sheath tape, the transposition yarn twist conductor was manufactured with the structure of the transposition yarn twist segment spirally wound on a frame, and the alternating current characteristics were investigated. As the result, the phase shift of transferring current could be hardly observed on the silver sheath wire in the segment. (NEDO)

  11. Highly relativistic radiation belt electron acceleration, transport, and loss: Large solar storm events of March and June 2015.

    Science.gov (United States)

    Baker, D N; Jaynes, A N; Kanekal, S G; Foster, J C; Erickson, P J; Fennell, J F; Blake, J B; Zhao, H; Li, X; Elkington, S R; Henderson, M G; Reeves, G D; Spence, H E; Kletzing, C A; Wygant, J R

    2016-07-01

    Two of the largest geomagnetic storms of the last decade were witnessed in 2015. On 17 March 2015, a coronal mass ejection-driven event occurred with a Dst (storm time ring current index) value reaching -223 nT. On 22 June 2015 another strong storm ( Dst reaching -204 nT) was recorded. These two storms each produced almost total loss of radiation belt high-energy ( E  ≳ 1 MeV) electron fluxes. Following the dropouts of radiation belt fluxes there were complex and rather remarkable recoveries of the electrons extending up to nearly 10 MeV in kinetic energy. The energized outer zone electrons showed a rich variety of pitch angle features including strong "butterfly" distributions with deep minima in flux at α  = 90°. However, despite strong driving of outer zone earthward radial diffusion in these storms, the previously reported "impenetrable barrier" at L  ≈ 2.8 was pushed inward, but not significantly breached, and no E  ≳ 2.0 MeV electrons were seen to pass through the radiation belt slot region to reach the inner Van Allen zone. Overall, these intense storms show a wealth of novel features of acceleration, transport, and loss that are demonstrated in the present detailed analysis.

  12. Highly Relativistic Radiation Belt Electron Acceleration, Transport, and Loss: Large Solar Storm Events of March and June 2015

    Science.gov (United States)

    Baker, D. N.; Jaynes, A. N.; Kanekal, S. G.; Foster, J.C.; Erickson, P. J.; Fennell, Joseph; Blake, J. B.; Zhao, H.; Li, X.; Elkington, S. R.; hide

    2016-01-01

    Two of the largest geomagnetic storms of the last decade were witnessed in 2015. On 17 March 2015, a coronal mass ejection-driven event occurred with a Dst (Disturbance Storm Time Ring Current Index) value reaching 223 nanoteslas. On 22 June 2015 another strong storm (Dst reaching 204 nanoteslas) was recorded. These two storms each produced almost total loss of radiation belt high-energy (E (Energy) greater than or approximately equal to 1 millielectronvolt) electron fluxes. Following the dropouts of radiation belt fluxes there were complex and rather remarkable recoveries of the electrons extending up to nearly 10 millielectronvolts in kinetic energy. The energized outer zone electrons showed a rich variety of pitch angle features including strong butterfly distributions with deep minima in flux at alpha equals 90 degrees. However, despite strong driving of outer zone earthward radial diffusion in these storms, the previously reported impenetrable barrier at L (L-shell magnetic field line value) approximately equal to 2.8 was pushed inward, but not significantly breached, and no E (Energy) greater than or approximately equal to 2.0 millielectronvolts electrons were seen to pass through the radiation belt slot region to reach the inner Van Allen zone. Overall, these intense storms show a wealth of novel features of acceleration, transport, and loss that are demonstrated in the present detailed analysis.

  13. Copolymer SJ-1 as a Fluid Loss Additive for Drilling Fluid with High Content of Salt and Calcium

    Directory of Open Access Journals (Sweden)

    Hongping Quan

    2014-01-01

    Full Text Available A ternary copolymer of 2-acrylamide-2-methyl propane sulfonic acid (AMPS, acrylamide (AM, and allyl alcohol polyoxyethylene ether (APEG with a side chain polyoxyethylene ether (C2H4On SJ-1 were designed and synthesized in this work. Good temperature resistance and salt tolerance of “–SO3-” of AMPS, strong absorption ability of “amino-group” of AM, and good hydrability of side chain polyoxyethylene ether (C2H4On of APEG provide SJ-1 excellent properties as a fluid loss additive. The chemical structure of ternary copolymer was characterized by Fourier transform infrared (FTIR spectroscopy. The molecular weight and its distribution were determined by gel permeation chromatography (GPC. The API fluid loss of drilling fluid decreased gradually with the increasing concentration of NaCl and CaCl2 in the mud system. SJ-1 was applied well in the drilling fluid even at a high temperature of 220°C. Results of zeta potential of modified drilling fluid showed the dispersion stability of drilling fluid system. Scanning electron microscopy (SEM analysis showed the microstructure of the surface of the filter cake obtained from the drilling fluid modified by SJ-1.

  14. High-Speed Atomic Force Microscopy Reveals Loss of Nuclear Pore Resilience as a Dying Code in Colorectal Cancer Cells.

    Science.gov (United States)

    Mohamed, Mahmoud Shaaban; Kobayashi, Akiko; Taoka, Azuma; Watanabe-Nakayama, Takahiro; Kikuchi, Yosuke; Hazawa, Masaharu; Minamoto, Toshinari; Fukumori, Yoshihiro; Kodera, Noriyuki; Uchihashi, Takayuki; Ando, Toshio; Wong, Richard W

    2017-06-27

    Nuclear pore complexes (NPCs) are the sole turnstile implanted in the nuclear envelope (NE), acting as a central nanoregulator of transport between the cytosol and the nucleus. NPCs consist of ∼30 proteins, termed nucleoporins. About one-third of nucleoporins harbor natively unstructured, intrinsically disordered phenylalanine-glycine strings (FG-Nups), which engage in transport selectivity. Because the barriers insert deeply in the NPC, they are nearly inaccessible. Several in vitro barrier models have been proposed; however, the dynamic FG-Nups protein molecules themselves are imperceptible in vivo. We show here that high-speed atomic force microscopy (HS-AFM) can be used to directly visualize nanotopographical changes of the nuclear pore inner channel in colorectal cancer (CRC) cells. Furthermore, using MLN8237/alisertib, an apoptotic and autophagic inducer currently being tested in relapsed cancer clinical trials, we unveiled the functional loss of nucleoporins, particularly the deformation of the FG-Nups barrier, in dying cancer cells. We propose that the loss of this nanoscopic resilience is an irreversible dying code in cells. These findings not only illuminate the potential application of HS-AFM as an intracellular nanoendoscopy but also might aid in the design of future nuclear targeted nanodrug delivery tailored to the individual patient.

  15. High resolution electron energy loss spectra (HREELS) of ultrathin Al sub 2 O sub 3 films on metal substrates

    CERN Document Server

    Lee, M B

    1999-01-01

    Long-range ordered Al sub O sub 3 films were prepared in a thickness range of 5 approx 30 A by oxidizing single-crystal NiAl(110) surfaces at a temperature between 300 and 1300 K. The typical phonon structure of the Al sub 2 O sub 3 films on NiAl(110) was investigated as a function of the probe electron beam energy and specular scattering angle by using HREELS (high resolution electron energy loss spectroscopy). The measured relative intensity of the distinct phonon features to the elastic peak follows well the general trends of the probe beam energy and angular dependence predicted by DT (dielectric theory) calculations. On a semi-empirical basis, the three phonon loss features, nu sub 1 (380 approx 430 cm sup - sup 1), nu sub 2 (620 approx 660 cm sup - sup 1), and nu sub 3 (850 approx 900 cm sup - sup 1), of crystalline Al sub 2 O sub 3 films were assigned to collective excitations of the microscopic vertical stretching motion of in-phase O-Al layers and to the stretching motions of the tetrahedrally and oc...

  16. ABR thresholds to tonebursts gated with Blackman and linear windows in adults with high-frequency sensorineural hearing loss.

    Science.gov (United States)

    Purdy, Suzanne C; Abbas, Paul J

    2002-08-01

    The goal of this study was to determine whether tonebursts gated on and off using a nonlinear, exact-Blackman-gating function would be a more frequency-specific stimulus for auditory brain stem response audiometry than the more traditional 2-1-2 cycle linearly gated toneburst. Toneburst ABRs were recorded in 10 adults with normal hearing and in 18 adults with sloping high-frequency sensorineural hearing loss. It was hypothesized that any advantage of the Blackman stimuli for frequency-specific threshold assessment should be evident in hearing-impaired subjects with hearing loss confined to the 2000 to 4000 Hz frequency region since spectral splatter in the toneburst stimuli could lead to an underestimation of hearing loss based on the ABR thresholds. ABR stimuli consisted of 2000- and 4000-Hz 2-1-2 (rise-plateau-fall) cycle linearly gated tonebursts and 1-0-1 msec exact-Blackman-gated tonebursts. An additional 0.5-0-0.5 msec 4000-Hz Blackman-gated toneburst was used to investigate whether the difference in rise/fall characteristics of the linearly and Blackman-gated tonebursts could account for any differences in ABR results at 4000 Hz. The ABR toneburst stimuli were calibrated behaviorally in 15 adults with normal hearing. In the normal-hearing listeners toneburst-ABR thresholds generally exceeded behavioral thresholds by 10 to 13 dB for all stimuli. Correlations of 0.85 to 0.96 were obtained between 2000 and 4000 Hz toneburst ABR thresholds and pure-tone audiometric thresholds in the hearing-impaired listeners. Results were similar for Blackman- and linearly gated stimuli. There were no clear differences between Blackman- and linearly gated tonebursts in terms of how well ABR thresholds predicted pure-tone thresholds at 2000 and 4000 Hz. In general audiometric thresholds were predicted with good accuracy (+/-15 dB) by the toneburst ABR thresholds. The 4000-Hz audiometric threshold was underestimated in one subject with a very steeply sloping hearing loss by both

  17. High-resolution genome-wide analysis of irradiated (UV and γ-rays) diploid yeast cells reveals a high frequency of genomic loss of heterozygosity (LOH) events.

    Science.gov (United States)

    St Charles, Jordan; Hazkani-Covo, Einat; Yin, Yi; Andersen, Sabrina L; Dietrich, Fred S; Greenwell, Patricia W; Malc, Ewa; Mieczkowski, Piotr; Petes, Thomas D

    2012-04-01

    In diploid eukaryotes, repair of double-stranded DNA breaks by homologous recombination often leads to loss of heterozygosity (LOH). Most previous studies of mitotic recombination in Saccharomyces cerevisiae have focused on a single chromosome or a single region of one chromosome at which LOH events can be selected. In this study, we used two techniques (single-nucleotide polymorphism microarrays and high-throughput DNA sequencing) to examine genome-wide LOH in a diploid yeast strain at a resolution averaging 1 kb. We examined both selected LOH events on chromosome V and unselected events throughout the genome in untreated cells and in cells treated with either γ-radiation or ultraviolet (UV) radiation. Our analysis shows the following: (1) spontaneous and damage-induced mitotic gene conversion tracts are more than three times larger than meiotic conversion tracts, and conversion tracts associated with crossovers are usually longer and more complex than those unassociated with crossovers; (2) most of the crossovers and conversions reflect the repair of two sister chromatids broken at the same position; and (3) both UV and γ-radiation efficiently induce LOH at doses of radiation that cause no significant loss of viability. Using high-throughput DNA sequencing, we also detected new mutations induced by γ-rays and UV. To our knowledge, our study represents the first high-resolution genome-wide analysis of DNA damage-induced LOH events performed in any eukaryote.

  18. Endocytic proteins drive vesicle growth via instability in high membrane tension environment

    CERN Document Server

    Walani, Nikhil; Agrawal, Ashutosh

    2015-01-01

    Clathrin-mediated endocytosis (CME) is a key pathway for transporting cargo into cells via membrane vesicles. It plays an integral role in nutrient import, signal transduction, neurotransmission and cellular entry of pathogens and drug-carrying nanoparticles. As CME entails substantial local remodeling of the plasma membrane, the presence of membrane tension offers resistance to bending and hence, vesicle formation. Experiments show that in such high tension conditions, actin dynamics is required to carry out CME successfully. In this study, we build upon these pioneering experimental studies to provide fundamental mechanistic insights into the roles of two key endocytic proteins, namely, actin and BAR proteins in driving vesicle formation in high membrane tension environment. Our study reveals a new actin force induced `snap-through instability' that triggers a rapid shape transition from a shallow invagination to a highly invaginated tubular structure. We show that the association of BAR proteins stabilizes...

  19. Bacillus cereus from the environment is genetically related to the highly pathogenic B. cereus in Zambia

    Science.gov (United States)

    OGAWA, Hirohito; OHNUMA, Miyuki; SQUARRE, David; MWEENE, Aaron Simanyengwe; EZAKI, Takayuki; FUJIKURA, Daisuke; OHNISHI, Naomi; THOMAS, Yuka; HANG’OMBE, Bernard Mudenda; HIGASHI, Hideaki

    2015-01-01

    To follow-up anthrax in Zambia since the outbreak in 2011, we have collected samples from the environment and the carcasses of anthrax-suspected animals, and have tried to isolate Bacillus anthracis. In the process of identification of B. anthracis, we collected two isolates, of which colonies were similar to B. anthracis; however, from the results of identification using the molecular-based methods, two isolates were genetically related to the highly pathogenic B. cereus, of which clinical manifestation is severe and fatal (e.g., pneumonia). In this study, we showed the existence of bacteria suspected to be highly pathogenic B. cereus in Zambia, indicating the possibility of an outbreak caused by highly pathogenic B. cereus. PMID:25797134

  20. Ubiquitous Green Computing Techniques for High Demand Applications in Smart Environments

    Directory of Open Access Journals (Sweden)

    Jose M. Moya

    2012-08-01

    Full Text Available Ubiquitous sensor network deployments, such as the ones found in Smart cities and Ambient intelligence applications, require constantly increasing high computational demands in order to process data and offer services to users. The nature of these applications imply the usage of data centers. Research has paid much attention to the energy consumption of the sensor nodes in WSNs infrastructures. However, supercomputing facilities are the ones presenting a higher economic and environmental impact due to their very high power consumption. The latter problem, however, has been disregarded in the field of smart environment services. This paper proposes an energy-minimization workload assignment technique, based on heterogeneity and application-awareness, that redistributes low-demand computational tasks from high-performance facilities to idle nodes with low and medium resources in the WSN infrastructure. These non-optimal allocation policies reduce the energy consumed by the whole infrastructure and the total execution time.

  1. Bacillus cereus from the environment is genetically related to the highly pathogenic B. cereus in Zambia.

    Science.gov (United States)

    Ogawa, Hirohito; Ohnuma, Miyuki; Squarre, David; Mweene, Aaron Simanyengwe; Ezaki, Takayuki; Fujikura, Daisuke; Ohnishi, Naomi; Thomas, Yuka; Hang'ombe, Bernard Mudenda; Higashi, Hideaki

    2015-08-01

    To follow-up anthrax in Zambia since the outbreak in 2011, we have collected samples from the environment and the carcasses of anthrax-suspected animals, and have tried to isolate Bacillus anthracis. In the process of identification of B. anthracis, we collected two isolates, of which colonies were similar to B. anthracis; however, from the results of identification using the molecular-based methods, two isolates were genetically related to the highly pathogenic B. cereus, of which clinical manifestation is severe and fatal (e.g., pneumonia). In this study, we showed the existence of bacteria suspected to be highly pathogenic B. cereus in Zambia, indicating the possibility of an outbreak caused by highly pathogenic B. cereus.

  2. Dinosaurs on the North Slope, Alaska: High latitude, latest cretaceous environments

    Science.gov (United States)

    Brouwers, E.M.; Clemens, W.A.; Spicer, R.A.; Ager, T.A.; Carter, L.D.; Sliter, W.V.

    1987-01-01

    Abundant skeletal remains demonstrate that lambeosaurine hadrosaurid, tyrannosaurid, and troodontid dinosaurs lived on the Alaskan North Slope during late Campanian-early Maestrichtian time (about 66 to 76 million years ago) in a deltaic environment dominated by herbaceous vegetation. The high ground terrestrial plant community was a mild- to cold-temperate forest composed of coniferous and broad leaf trees. The high paleolatitude (about 70?? to 85?? North) implies extreme seasonal variation in solar insolation, temperature, and herbivore food supply. Great distances of migration to contemporaneous evergreen floras and the presence of both juvenile and adult hadrosaurs suggest that they remained at high latitudes year-round. This challenges the hypothesis that short-term periods of darkness and temperature decrease resulting from a bolide impact caused dinosaurian extinction.

  3. Understanding Fundamental Material Degradation Processes in High Temperature Aggressive Chemomechanical Environments

    Energy Technology Data Exchange (ETDEWEB)

    Stubbins, James; Gewirth, Andrew; Sehitoglu, Huseyin; Sofronis, Petros; Robertson, Ian

    2014-01-16

    The objective of this project is to develop a fundamental understanding of the mechanisms that limit materials durability for very high-temperature applications. Current design limitations are based on material strength and corrosion resistance. This project will characterize the interactions of high-temperature creep, fatigue, and environmental attack in structural metallic alloys of interest for the very high-temperature gas-cooled reactor (VHTR) or Next–Generation Nuclear Plant (NGNP) and for the associated thermo-chemical processing systems for hydrogen generation. Each of these degradation processes presents a major materials design challenge on its own, but in combination, they can act synergistically to rapidly degrade materials and limit component lives. This research and development effort will provide experimental results to characterize creep-fatigue-environment interactions and develop predictive models to define operation limits for high-temperature structural material applications. Researchers will study individually and in combination creep-fatigue-environmental attack processes in Alloys 617, 230, and 800H, as well as in an advanced Ni-Cr oxide dispersion strengthened steel (ODS) system. For comparison, the study will also examine basic degradation processes in nichrome (Ni-20Cr), which is a basis for most high-temperature structural materials, as well as many of the superalloys. These materials are selected to represent primary candidate alloys, one advanced developmental alloy that may have superior high-temperature durability, and one model system on which basic performance and modeling efforts can be based. The research program is presented in four parts, which all complement each other. The first three are primarily experimental in nature, and the last will tie the work together in a coordinated modeling effort. The sections are (1) dynamic creep-fatigue-environment process, (2) subcritical crack processes, (3) dynamic corrosion – crack

  4. The High School Environment and the Gender Gap in Science and Engineering

    Science.gov (United States)

    Legewie, Joscha; DiPrete, Thomas A.

    2016-01-01

    Despite the striking reversal of the gender gap in education, women pursue science, technology, engineering, and mathematics (STEM) degrees at much lower rates than those of their male peers. This study extends existing explanations for these gender differences and examines the role of the high school context for plans to major in STEM fields. Building on recent gender theories, we argue that widely shared and hegemonic gender beliefs manifest differently across schools so that the gender-specific formation of study plans is shaped by the local environment of high schools. Using the National Education Longitudinal Study, we first show large variations between high schools in the ability to attract students to STEM fields conditional on a large set of pre–high school measures. Schools that are successful in attracting students to these fields reduce the gender gap by 25 percent or more. As a first step toward understanding what matters about schools, we then estimate the effect of two concrete high school characteristics on plans to major in STEM fields in college—a high school's curriculum in STEM and gender segregation of extracurricular activities. These factors have a substantial effect on the gender gap in plans to major in STEM: a finding that is reaffirmed in a number of sensitivity analyses. Our focus on the high school context opens concrete avenues for policy intervention and is of central theoretical importance to understand the gender gap in orientations toward STEM fields. PMID:27857451

  5. Exploring the Potential of Aerial Photogrammetry for 3d Modelling of High-Alpine Environments

    Science.gov (United States)

    Legat, K.; Moe, K.; Poli, D.; Bollmannb, E.

    2016-03-01

    High-alpine areas are subject to rapid topographic changes, mainly caused by natural processes like glacial retreat and other geomorphological processes, and also due to anthropogenic interventions like construction of slopes and infrastructure in skiing resorts. Consequently, the demand for highly accurate digital terrain models (DTMs) in alpine environments has arisen. Public administrations often have dedicated resources for the regular monitoring of glaciers and natural hazard processes. In case of glaciers, traditional monitoring encompasses in-situ measurements of area and length and the estimation of volume and mass changes. Next to field measurements, data for such monitoring programs can be derived from DTMs and digital ortho photos (DOPs). Skiing resorts, on the other hand, require DTMs as input for planning and - more recently - for RTK-GNSS supported ski-slope grooming. Although different in scope, the demand of both user groups is similar: high-quality and up-to-date terrain data for extended areas often characterised by difficult accessibility and large elevation ranges. Over the last two decades, airborne laser scanning (ALS) has replaced photogrammetric approaches as state-of-the-art technology for the acquisition of high-resolution DTMs also in alpine environments. Reasons include the higher productivity compared to (manual) stereo-photogrammetric measurements, canopy-penetration capability, and limitations of photo measurements on sparsely textured surfaces like snow or ice. Nevertheless, the last few years have shown strong technological advances in the field of aerial camera technology, image processing and photogrammetric software which led to new possibilities for image-based DTM generation even in alpine terrain. At Vermessung AVT, an Austrian-based surveying company, and its subsidiary Terra Messflug, very promising results have been achieved for various projects in high-alpine environments, using images acquired by large-format digital

  6. Depth imaging in highly scattering underwater environments using time-correlated single-photon counting

    Science.gov (United States)

    Maccarone, Aurora; McCarthy, Aongus; Halimi, Abderrahim; Tobin, Rachael; Wallace, Andy M.; Petillot, Yvan; McLaughlin, Steve; Buller, Gerald S.

    2016-10-01

    This paper presents an optical depth imaging system optimized for highly scattering environments such as underwater. The system is based on the time-correlated single-photon counting (TCSPC) technique and the time-of-flight approach. Laboratory-based measurements demonstrate the potential of underwater depth imaging, with specific attention given to environments with a high level of scattering. The optical system comprised a monostatic transceiver unit, a fiber-coupled supercontinuum laser source with a wavelength tunable acousto-optic filter (AOTF), and a fiber-coupled single-element silicon single-photon avalanche diode (SPAD) detector. In the optical system, the transmit and receive channels in the transceiver unit were overlapped in a coaxial optical configuration. The targets were placed in a 1.75 meter long tank, and raster scanned using two galvo-mirrors. Laboratory-based experiments demonstrate depth profiling performed with up to nine attenuation lengths between the transceiver and target. All of the measurements were taken with an average laser power of less than 1mW. Initially, the data was processed using a straightforward pixel-wise cross-correlation of the return timing signal with the system instrumental timing response. More advanced algorithms were then used to process these cross-correlation results. These results illustrate the potential for the reconstruction of images in highly scattering environments, and to permit the investigation of much shorter acquisition time scans. These algorithms take advantage of the data sparseness under the Discrete Cosine Transform (DCT) and the correlation between adjacent pixels, to restore the depth and reflectivity images.

  7. A compact 3D omnidirectional range sensor of high resolution for robust reconstruction of environments.

    Science.gov (United States)

    Marani, Roberto; Renò, Vito; Nitti, Massimiliano; D'Orazio, Tiziana; Stella, Ettore

    2015-01-22

    In this paper, an accurate range sensor for the three-dimensional reconstruction of environments is designed and developed. Following the principles of laser profilometry, the device exploits a set of optical transmitters able to project a laser line on the environment. A high-resolution and high-frame-rate camera assisted by a telecentric lens collects the laser light reflected by a parabolic mirror, whose shape is designed ad hoc to achieve a maximum measurement error of 10 mm when the target is placed 3 m away from the laser source. Measurements are derived by means of an analytical model, whose parameters are estimated during a preliminary calibration phase. Geometrical parameters, analytical modeling and image processing steps are validated through several experiments, which indicate the capability of the proposed device to recover the shape of a target with high accuracy. Experimental measurements show Gaussian statistics, having standard deviation of 1.74 mm within the measurable range. Results prove that the presented range sensor is a good candidate for environmental inspections and measurements.

  8. Nursing care in a high-technological environment: Experiences of critical care nurses.

    Science.gov (United States)

    Tunlind, Adam; Granström, John; Engström, Åsa

    2015-04-01

    Management of technical equipment, such as ventilators, infusion pumps, monitors and dialysis, makes health care in an intensive care setting more complex. Technology can be defined as items, machinery and equipment that are connected to knowledge and management to maximise efficiency. Technology is not only the equipment itself, but also the knowledge of how to use it and the ability to convert it into nursing care. The aim of this study is to describe critical care nurses' experience of performing nursing care in a high technology healthcare environment. Qualitative, personal interviews were conducted during 2012 with eight critical care nurses in the northern part of Sweden. Interview transcripts were analysed using qualitative content analysis. Three themes with six categories emerged. The technology was described as a security that could facilitate nursing care, but also one that could sometimes present obstacles. The importance of using the clinical gaze was highlighted. Nursing care in a high technological environment must be seen as multi-faceted when it comes to how it affects CCNs' experience. The advanced care conducted in an ICU could not function without high-tech equipment, nor could care operate without skilled interpersonal interaction and maintenance of basal nursing. That technology is seen as a major tool and simultaneously as a barrier to patient-centred care. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Spectral correction factors for conventional neutron dosemeters used in high-energy neutron environments.

    Science.gov (United States)

    Lee, K W; Sheu, R J

    2015-04-01

    High-energy neutrons (>10 MeV) contribute substantially to the dose fraction but result in only a small or negligible response in most conventional moderated-type neutron detectors. Neutron dosemeters used for radiation protection purpose are commonly calibrated with (252)Cf neutron sources and are used in various workplace. A workplace-specific correction factor is suggested. In this study, the effect of the neutron spectrum on the accuracy of dose measurements was investigated. A set of neutron spectra representing various neutron environments was selected to study the dose responses of a series of Bonner spheres, including standard and extended-range spheres. By comparing (252)Cf-calibrated dose responses with reference values based on fluence-to-dose conversion coefficients, this paper presents recommendations for neutron field characterisation and appropriate correction factors for responses of conventional neutron dosemeters used in environments with high-energy neutrons. The correction depends on the estimated percentage of high-energy neutrons in the spectrum or the ratio between the measured responses of two Bonner spheres (the 4P6_8 extended-range sphere versus the 6″ standard sphere). © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. A Compact 3D Omnidirectional Range Sensor of High Resolution for Robust Reconstruction of Environments

    Directory of Open Access Journals (Sweden)

    Roberto Marani

    2015-01-01

    Full Text Available In this paper, an accurate range sensor for the three-dimensional reconstruction of environments is designed and developed. Following the principles of laser profilometry, the device exploits a set of optical transmitters able to project a laser line on the environment. A high-resolution and high-frame-rate camera assisted by a telecentric lens collects the laser light reflected by a parabolic mirror, whose shape is designed ad hoc to achieve a maximum measurement error of 10 mm when the target is placed 3 m away from the laser source. Measurements are derived by means of an analytical model, whose parameters are estimated during a preliminary calibration phase. Geometrical parameters, analytical modeling and image processing steps are validated through several experiments, which indicate the capability of the proposed device to recover the shape of a target with high accuracy. Experimental measurements show Gaussian statistics, having standard deviation of 1.74 mm within the measurable range. Results prove that the presented range sensor is a good candidate for environmental inspections and measurements.

  11. High-fat Diet Enhances and Plasminogen Activator Inhibitor-1 Deficiency Attenuates Bone Loss in Mice with Lewis Lung Carcinoma.

    Science.gov (United States)

    Yan, Lin; Nielsen, Forrest H; Sundaram, Sneha; Cao, Jay

    2015-07-01

    This study determined the effects of a high-fat diet and plasminogen activator inhibitor-1 deficiency (Pai1(-/-)) on the bone structure in male C57BL/6 mice bearing Lewis lung carcinoma (LLC) in lungs. Significant reduction in bone volume fraction (BV/TV), trabecular number (Tb.N) and bone mineral density (BMD) in femurs and vertebrae were found in LLC-bearing mice compared to non-tumor-bearing mice. In LLC-bearing mice, the high-fat diet compared to the AIN93G control diet significantly reduced BV/TV, Tb.N and BMD in femurs and BV/TV in vertebrae. The high-fat diet significantly reduced BMD in vertebrae in wild-type mice but not in Pai1(-/-) mice. Compared to wild-type mice, PAI1 deficiency significantly increased BV/TV and Tb.N in femurs. The plasma concentration of osteocalcin was significantly lower and that of tartrate-resistant acid phosphatase 5b (TRAP5b) was significantly higher in LLC-bearing mice. The high-fat diet significantly reduced plasma osteocalcin and increased TRAP5b. Deficiency in PAI1 prevented the high-fat diet-induced increases in plasma TRAP5b. These findings demonstrate that a high-fat diet enhances, whereas PAI1 deficiency, attenuates metastasis-associated bone loss, indicating that a high-fat diet and PAI1 contribute to metastasis-associated bone deterioration. Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  12. High-energy-resolution monochromator for aberration-corrected scanning transmission electron microscopy/electron energy-loss spectroscopy.

    Science.gov (United States)

    Krivanek, Ondrej L; Ursin, Jonathan P; Bacon, Neil J; Corbin, George J; Dellby, Niklas; Hrncirik, Petr; Murfitt, Matthew F; Own, Christopher S; Szilagyi, Zoltan S

    2009-09-28

    An all-magnetic monochromator/spectrometer system for sub-30 meV energy-resolution electron energy-loss spectroscopy in the scanning transmission electron microscope is described. It will link the energy being selected by the monochromator to the energy being analysed by the spectrometer, without resorting to decelerating the electron beam. This will allow it to attain spectral energy stability comparable to systems using monochromators and spectrometers that are raised to near the high voltage of the instrument. It will also be able to correct the chromatic aberration of the probe-forming column. It should be able to provide variable energy resolution down to approximately 10 meV and spatial resolution less than 1 A.

  13. Habitat foraging niche of a High Arctic zooplanktivorous seabird in a changing environment.

    Science.gov (United States)

    Jakubas, Dariusz; Wojczulanis-Jakubas, Katarzyna; Iliszko, Lech M; Strøm, Hallvard; Stempniewicz, Lech

    2017-11-24

    Here, we model current and future distribution of a foraging Arctic endemic species, the little auk (Alle alle), a small zooplanktivorous Arctic seabird. We characterized environmental conditions [sea depth, sea surface temperature (SST), marginal sea ice zone (MIZ)] at foraging positions of GPS-tracked individuals from three breeding colonies in Svalbard: one located at the southern rim of the Arctic zone (hereafter 'boreo-Arctic') and two in the high-Arctic zone on Spitsbergen ('high-Arctic'). The birds from one 'high-Arctic' colony, influenced by cold Arctic water, foraged in the shallow shelf zone near the colony. The birds from remaining colonies foraged in a wider range of depths, in a higher SST zone ('boreo-Arctic') or in the productive but distant MIZ (second 'high-Arctic' colony). Given this flexible foraging behaviour, little auks may be temporarily resilient to moderate climate changes. However, our fuzzy logic models of future distribution under scenarios of 1 °C and 2 °C SST increase predict losses of suitable foraging habitat for the majority of little auk colonies studied. Over longer time scales negative consequences of global warming are inevitable. The actual response of little auks to future environmental conditions will depend on the range of their plasticity and pace of ecosystem changes.

  14. Programming Environment for a High-Performance Parallel Supercomputer with Intelligent Communication

    Directory of Open Access Journals (Sweden)

    A. Gunzinger

    1996-01-01

    Full Text Available At the Electronics Laboratory of the Swiss Federal Institute of Technology (ETH in Zürich, the high-performance parallel supercomputer MUSIC (MUlti processor System with Intelligent Communication has been developed. As applications like neural network simulation and molecular dynamics show, the Electronics Laboratory supercomputer is absolutely on par with those of conventional supercomputers, but electric power requirements are reduced by a factor of 1,000, weight is reduced by a factor of 400, and price is reduced by a factor of 100. Software development is a key issue of such parallel systems. This article focuses on the programming environment of the MUSIC system and on its applications.

  15. GaN-Based High Temperature and Radiation-Hard Electronics for Harsh Environments

    Science.gov (United States)

    Son, Kyung-ah; Liao, Anna; Lung, Gerald; Gallegos, Manuel; Hatakeh, Toshiro; Harris, Richard D.; Scheick, Leif Z.; Smythe, William D.

    2010-01-01

    We develop novel GaN-based high temperature and radiation-hard electronics to realize data acquisition electronics and transmitters suitable for operations in harsh planetary environments. In this paper, we discuss our research on metal-oxide-semiconductor (MOS) transistors that are targeted for 500 (sup o)C operation and >2 Mrad radiation hardness. For the target device performance, we develop Schottky-free AlGaN/GaN MOS transistors, where a gate electrode is processed in a MOS layout using an Al2O3 gate dielectric layer....

  16. Integrating INIS into a high energy physics information environment thoughts from CERN

    CERN Document Server

    Yeomans, Joanne; Baudic, Romain; Picchioli, Ingrid; International Conference on Nuclear Knowledge Management : Strategies, Information Management and Human Resource Development. Special Session : The Role of INIS in Knowledge Preservation

    2004-01-01

    Information searchers from the high energy physics community expect an integrated information environment. The CERN Library offers its print and electronic collections through a combined Web interface and maintains the database by semi-automated processes to upload bibliographic and full-text records. Suggestions are offered by which INIS could develop its own Web interface and better match HEP users’ expectations. These include implementing full-text linking, increasing currency, expanding search and display functions and developing the richness of the data. Links with the National Nuclear Data Center and Crossref could also increase its visibility.

  17. Liquid-propellant droplet vaporization and combustion in high pressure environments

    Science.gov (United States)

    Yang, Vigor

    1991-01-01

    In order to correct the deficiencies of existing models for high-pressure droplet vaporization and combustion, a fundamental investigation into this matter is essential. The objective of this research are: (1) to acquire basic understanding of physical and chemical mechanisms involved in the vaporization and combustion of isolated liquid-propellant droplets in both stagnant and forced-convective environments; (2) to establish droplet vaporization and combustion correlations for the study of liquid-propellant spray combustion and two-phase flowfields in rocket motors; and (3) to investigate the dynamic responses of multicomponent droplet vaporization and combustion to ambient flow oscillations.

  18. Evidence for a Cr metastable phase as a tracer in DLI-MOCVD chromium hard coatings usable in high temperature environment

    Science.gov (United States)

    Michau, Alexandre; Maury, Francis; Schuster, Frederic; Boichot, Raphael; Pons, Michel

    2017-11-01

    Cr deposits are widely used as protective coatings but multifunctional performances are required in harsh environments motivating research on new processes. MOCVD of Cr metal coatings was carried out by direct liquid injection (DLI) of a unique solution containing bis(ethylbenzene)chromium as metal source and thiophenol as inhibitor of carbide formation. A low amount (affected by the structural transformation because of the similarity of their crystallographic structures (both cubic), their density very close (a volume contraction of only 0.4% during the transformation) and its low content. This metastable phase is a signature of the DLI-MOCVD process and it can be used as a tracer for Cr coatings operating in high temperature environment without loss of the basic properties.

  19. ROLE OF RS9939609 FTO GENE VARIANT IN WEIGHT LOSS, INSULIN RESISTANCE AND METABOLIC PARAMETERS AFTER A HIGH MONOUNSATURATED VS A HIGH POLYUNSATURATED FAT HYPOCALORIC DIETS.

    Science.gov (United States)

    De Luis, Daniel Antonio; Aller, Rocío; Izaola, Olatz; Pacheco, D

    2015-07-01

    common polymorphisms (rs9939609) of the fat mass and obesity associated gene (FTO) have been linked to obesity. our aim was to investigate the role of this polymorphism on insulin resistance, metabolic changes and weight loss secondary to a high monounsaturated fat vs a high polyunsaturated fat hypocaloric diets. a sample of 233 obese subjects was enrolled in a prospective way. In the basal visit, patients were randomly allocated during 3 months to; Diet M (high monounsaturated fat hypocaloric diet) or Diet P (high polyunsaturated fat hypocaloric diet). after treatment with two diets and in both genotypes, weight, fat mass and waist circumference decreased. Lower levels of body mass index (BMI), weight and fat mass were detected after Diet P in A allele carriers than TT genotype subjects. With the diet type P and in both genotypes (TT and AT + AA), total cholesterol levels (-15.3 + 35.1 mg/dl vs -11.6 + 32.1 mg/dl: p > 0.05) and LDL cholesterol levels (-11.5 + 34.1 mg/dl vs -8.5 + 30.1 mg/dl: p > 0.05) decreased. In A allele carriers a significant decreased was detected in insulin levels (-2.8 + 2.1 UI/L vs -1.3 + 8.0 UI/L: p 0.05), too. With the diet M and in both genotype groups, leptin levels (-8.0 + 17.1 ng/ ml vs -4.9 + 18.7 ng/ml: p > 0.05) decreased. Conclusiones: metabolic improvement secondary to weight loss was better in A carriers with a high polyunsaturated fat hypocaloric diet. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

  20. High adsorption rate is detrimental to bacteriophage fitness in a biofilm-like environment

    Directory of Open Access Journals (Sweden)

    Shao Yongping

    2009-10-01

    Full Text Available Abstract Background Bacterial biofilm is ubiquitous in nature. However, it is not clear how this crowded habitat would impact the evolution of bacteriophage (phage life history traits. In this study, we constructed isogenic λ phage strains that only differed in their adsorption rates, because of the presence/absence of extra side tail fibers or improved tail fiber J, and maker states. The high cell density and viscosity of the biofilm environment was approximated by the standard double-layer agar plate. The phage infection cycle in the biofilm environment was decomposed into three stages: settlement on to the biofilm surface, production of phage progeny inside the biofilm, and emigration of phage progeny out of the current focus of infection. Results We found that in all cases high adsorption rate is beneficial for phage settlement, but detrimental to phage production (in terms of plaque size and productivity and emigration out of the current plaque. Overall, the advantage of high adsorption accrued during settlement is more than offset by the disadvantages experienced during the production and emigration stages. The advantage of low adsorption rate was further demonstrated by the rapid emergence of low-adsorption mutant from a high-adsorption phage strain with the side tail fibers. DNA sequencing showed that 19 out of the 21 independent mutant clones have mutations in the stf gene, with the majority of them being single-nucleotide insertion/deletion mutations occurring in regions with homonucleotide runs. Conclusion We conclude that high mutation rate of the stf gene would ensure the existence of side tail fiber polymorphism, thus contributing to rapid adaptation of the phage population between diametrically different habitats of benthic biofilm and planktonic liquid culture. Such adaptability would also help to explain the maintenance of the stf gene in phage λ's genome.

  1. High adsorption rate is detrimental to bacteriophage fitness in a biofilm-like environment.

    Science.gov (United States)

    Gallet, Romain; Shao, Yongping; Wang, Ing-Nang

    2009-10-05

    Bacterial biofilm is ubiquitous in nature. However, it is not clear how this crowded habitat would impact the evolution of bacteriophage (phage) life history traits. In this study, we constructed isogenic lambda phage strains that only differed in their adsorption rates, because of the presence/absence of extra side tail fibers or improved tail fiber J, and maker states. The high cell density and viscosity of the biofilm environment was approximated by the standard double-layer agar plate. The phage infection cycle in the biofilm environment was decomposed into three stages: settlement on to the biofilm surface, production of phage progeny inside the biofilm, and emigration of phage progeny out of the current focus of infection. We found that in all cases high adsorption rate is beneficial for phage settlement, but detrimental to phage production (in terms of plaque size and productivity) and emigration out of the current plaque. Overall, the advantage of high adsorption accrued during settlement is more than offset by the disadvantages experienced during the production and emigration stages. The advantage of low adsorption rate was further demonstrated by the rapid emergence of low-adsorption mutant from a high-adsorption phage strain with the side tail fibers. DNA sequencing showed that 19 out of the 21 independent mutant clones have mutations in the stf gene, with the majority of them being single-nucleotide insertion/deletion mutations occurring in regions with homonucleotide runs. We conclude that high mutation rate of the stf gene would ensure the existence of side tail fiber polymorphism, thus contributing to rapid adaptation of the phage population between diametrically different habitats of benthic biofilm and planktonic liquid culture. Such adaptability would also help to explain the maintenance of the stf gene in phage lambda's genome.

  2. Effect of high ambient temperature on behavior of sheep under semi-arid tropical environment.

    Science.gov (United States)

    De, Kalyan; Kumar, Davendra; Saxena, Vijay Kumar; Thirumurugan, Palanisamy; Naqvi, Syed Mohammed Khursheed

    2017-07-01

    High environmental temperature is a major constraint in sheep production under semi-arid tropical environment. Behavior is the earliest indicator of animal's adaptation and responses to the environmental alteration. Therefore, the objective of this study was to assess the effects of high ambient temperature on the behavior of sheep under a semi-arid tropical environment. The experiment was conducted for 6 weeks on 16 Malpura cross (Garole × Malpura × Malpura (GMM)) rams. The rams were divided equally into two groups, designated as C and T. The rams of C were kept in comfortable environmental conditions served as control. The rams of T were exposed to a different temperature at different hours of the day in a climatic chamber, to simulate a high environmental temperature of summer in semi-arid tropic. The behavioral observations were taken by direct instantaneous observation at 15-min intervals for each animal individually. The feeding, ruminating, standing, and lying behaviors were recorded twice a week from morning (0800 hours) to afternoon (1700 hours) for 6 weeks. Exposure of rams to high temperature (T) significantly (P < 0.05) decreased the proportion of time spent in feeding during the observation period in most of the hours of the day as compared to the C. The proportion of time spent in rumination and lying was significantly (P < 0.05) lower in the T group compared to the C. The animals of T spent significantly (P < 0.05) more time in rumination in standing position as compared to the C. The overall proportion of time spent in standing, panting in each hour, and total panting time was significantly (P < 0.05) higher in the T as compared to the C. The result of the study indicates that the exposure of sheep to high ambient temperature severely modulates the behavior of sheep which is directed to circumvent the effect of the stressor.

  3. Unravelling the origin of irreversible capacity loss in NaNiO 2 for high voltage sodium ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Liguang; Wang, Jiajun; Zhang, Xiaoyi; Ren, Yang; Zuo, Pengjian; Yin, Geping; Wang, Jun

    2017-04-01

    Layered transition metal compounds have attracted much attention due to their high theoretical capacity and energy density for sodium ion batteries. However, this kind of material suffers from serious irreversible capacity decay during the charge and discharge process. Here, using synchrotron-based operando transmission X-ray microscopy and high-energy X-ray diffraction combined with electrochemical measurements, the visualization of the dissymmetric phase transformation and structure evolution mechanism of layered NaNiO2 material during initial charge and discharge cycles are clarified. Phase transformation and deformation of NaNiO2 during the voltage range of below 3.0 V and over 4.0 V are responsible for the irreversible capacity loss during the first cycling, which is also confirmed by the evolution of reaction kinetics behavior obtained by the galvanostatic intermittent titration technique. These findings reveal the origin of the irreversibility of NaNiO2 and offer valuable insight into the phase transformation mechanism, which will provide underlying guidance for further development of high-performance sodium ion batteries.

  4. Path Planning for Non-Circular, Non-Holonomic Robots in Highly Cluttered Environments.

    Science.gov (United States)

    Samaniego, Ricardo; Lopez, Joaquin; Vazquez, Fernando

    2017-08-15

    This paper presents an algorithm for finding a solution to the problem of planning a feasible path for a slender autonomous mobile robot in a large and cluttered environment. The presented approach is based on performing a graph search on a kinodynamic-feasible lattice state space of high resolution; however, the technique is applicable to many search algorithms. With the purpose of allowing the algorithm to consider paths that take the robot through narrow passes and close to obstacles, high resolutions are used for the lattice space and the control set. This introduces new challenges because one of the most computationally expensive parts of path search based planning algorithms is calculating the cost of each one of the actions or steps that could potentially be part of the trajectory. The reason for this is that the evaluation of each one of these actions involves convolving the robot's footprint with a portion of a local map to evaluate the possibility of a collision, an operation that grows exponentially as the resolution is increased. The novel approach presented here reduces the need for these convolutions by using a set of offline precomputed maps that are updated, by means of a partial convolution, as new information arrives from sensors or other sources. Not only does this improve run-time performance, but it also provides support for dynamic search in changing environments. A set of alternative fast convolution methods are also proposed, depending on whether the environment is cluttered with obstacles or not. Finally, we provide both theoretical and experimental results from different experiments and applications.

  5. IASCC susceptibility of austenitic stainless steels and alloy 690 in high dissolved oxygen water environment

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Y.; Chopra, O.K.; Soppet, W.K. [Argonne National Lab., Nuclear Engineering Div., Argonne, Illinois (United States); Dietz Rago, N.L. [Argonne National Lab., Chemical Engineering Div., Argonne, Illinois (United States); Shack, W.J. [Argonne National Lab., Nuclear Engineering Div., Argonne, Illinois (United States)

    2007-07-01

    The influences of grain boundary engineering, alloying elements, and neutron dose on irradiation-assisted stress corrosion cracking (IASCC) of austenitic stainless steels and Alloy 690 were investigated. Flat dog-bone specimens irradiated in the Halden boiling heavy water reactor to {approx}2 dpa were tested in slow strain rate tensile tests in high dissolved oxygen water at 289 {sup o}C. The area fractions of intergranular or transgranular fracture were measured using a scanning electron microscope. All tested materials showed significant hardening and loss of ductility after irradiation. The area fractions of the intergranular cracking decreased with increase of uniform elongation, and were used to rank IASCC susceptibility. The grain boundary engineering treatment employed in this study does not have a significant impact on IASCC susceptibility for austenitic SSs at {approx}2 dpa, but does affect the cracking behavior of Alloy 690. High-sulfur and low-carbon SSs are more susceptible to IASCC. Oxygen content also contributes to the IASCC susceptibility in high-purity Type 304L SS. (author)

  6. Localized corrosion of high performance metal alloys in an acid/salt environment

    Science.gov (United States)

    Macdowell, L. G.; Ontiveros, C.

    1991-01-01

    Various vacuum jacketed cryogenic supply lines at the Space Shuttle launch site at Kennedy Space Center use convoluted flexible expansion joints. The atmosphere at the launch site has a very high salt content, and during a launch, fuel combustion products include hydrochloric acid. This extremely corrosive environment has caused pitting corrosion failure in the thin walled 304L stainless steel flex hoses. A search was done to find a more corrosion resistant replacement material. The study focussed on 19 metal alloys. Tests which were performed include electrochemical corrosion testing, accelerated corrosion testing in a salt fog chamber, and long term exposure at a beach corrosion testing site. Based on the results of these tests, several nickel based alloys were found to have very high resistance to this corrosive environment. Also, there was excellent agreement between the electrochemical tests and the actual beach exposure tests. This suggests that electrochemical testing may be useful for narrowing the field of potential candidate alloys before subjecting samples to long term beach exposure.

  7. An empirical model of the high-energy electron environment at Jupiter

    Science.gov (United States)

    Soria-Santacruz, M.; Garrett, H. B.; Evans, R. W.; Jun, I.; Kim, W.; Paranicas, C.; Drozdov, A.

    2016-10-01

    We present an empirical model of the energetic electron environment in Jupiter's magnetosphere that we have named the Galileo Interim Radiation Electron Model version-2 (GIRE2) since it is based on Galileo data from the Energetic Particle Detector (EPD). Inside 8RJ, GIRE2 adopts the previously existing model of Divine and Garrett because this region was well sampled by the Pioneer and Voyager spacecraft but poorly covered by Galileo. Outside of 8RJ, the model is based on 10 min averages of Galileo EPD data as well as on measurements from the Geiger Tube Telescope on board the Pioneer spacecraft. In the inner magnetosphere the field configuration is dipolar, while in the outer magnetosphere it presents a disk-like structure. The gradual transition between these two behaviors is centered at about 17RJ. GIRE2 distinguishes between the two different regions characterized by these two magnetic field topologies. Specifically, GIRE2 consists of an inner trapped omnidirectional model between 8 to 17RJ that smoothly joins onto the original Divine and Garrett model inside 8RJ and onto a GIRE2 plasma sheet model at large radial distances. The model provides a complete picture of the high-energy electron environment in the Jovian magnetosphere from ˜1 to 50RJ. The present manuscript describes in great detail the data sets, formulation, and fittings used in the model and provides a discussion of the predicted high-energy electron fluxes as a function of energy and radial distance from the planet.

  8. A High-Fidelity Batch Simulation Environment for Integrated Batch and Piloted Air Combat Simulation Analysis

    Science.gov (United States)

    Goodrich, Kenneth H.; McManus, John W.; Chappell, Alan R.

    1992-01-01

    A batch air combat simulation environment known as the Tactical Maneuvering Simulator (TMS) is presented. The TMS serves as a tool for developing and evaluating tactical maneuvering logics. The environment can also be used to evaluate the tactical implications of perturbations to aircraft performance or supporting systems. The TMS is capable of simulating air combat between any number of engagement participants, with practical limits imposed by computer memory and processing power. Aircraft are modeled using equations of motion, control laws, aerodynamics and propulsive characteristics equivalent to those used in high-fidelity piloted simulation. Databases representative of a modern high-performance aircraft with and without thrust-vectoring capability are included. To simplify the task of developing and implementing maneuvering logics in the TMS, an outer-loop control system known as the Tactical Autopilot (TA) is implemented in the aircraft simulation model. The TA converts guidance commands issued by computerized maneuvering logics in the form of desired angle-of-attack and wind axis-bank angle into inputs to the inner-loop control augmentation system of the aircraft. This report describes the capabilities and operation of the TMS.

  9. The Inchworm as a precision translator in a high magnetic field and uhv environment

    Energy Technology Data Exchange (ETDEWEB)

    Becker, P.; Becker, St.; Bollen, G.; Kluge, H.-J.; Savard, G.; Stampp, W.; Stolzenberg, H. (Mainz Univ. (Germany, F.R.). Inst. fuer Physik European Organization for Nuclear Research, Geneva (Switzerland))

    1990-01-01

    A new set-up has been designed and tested for on-line, high-precision mass measurements of short-lived radioactive isotopes via a determination of the ion cyclotron resonance. Ions delivered by the on-line isotope separator ISOLDE at CERN/Geneva are stored in a Penning trap installed in a superconducting solenoid. Due to severe space limitations in the bore of the solenoid, it is impossible to use conventional mechanical feedthroughs for the necessary manipulations inside the uhv chamber. Instead, a number of inchworms, a high-precision positioning device based on the piezo-electric effect are employed. This publication reports on the first application of this device in a uhv environment at a magnetic field of nearly 6 T. (author).

  10. Multiple antibiotic resistance indexing of coliforms to identify high risk contamination sites in aquatic environment.

    Science.gov (United States)

    Chitanand, M P; Kadam, T A; Gyananath, G; Totewad, N D; Balhal, D K

    2010-06-01

    Bacteriological analysis of the water samples collected from upstream, midstream and downstream points along the bank of the river revealed high populations of Escherichia coli, Citrobacter freundii, Citrobacter diversus, Enterobacter aerogens and Klebsiella species. All these isolates were screened against eight antibiotics to determine the prevalence of multiple antibiotic resistance among isolates at different sites of the river. The study revealed that multiple antibiotic resistance was prominently seen in coliforms at downstream sites (Average multiple antibiotic resistance index, MAR Index = 0.43) while it was low in coliforms at upstream sites (MAR Index = 0.15). These differences in MAR indices provide a method for distinguishing high risk contamination sites in aquatic environment.

  11. Reusable Object-Oriented Solutions for Numerical Simulation of PDEs in a High Performance Environment

    Directory of Open Access Journals (Sweden)

    Andrea Lani

    2006-01-01

    Full Text Available Object-oriented platforms developed for the numerical solution of PDEs must combine flexibility and reusability, in order to ease the integration of new functionalities and algorithms. While designing similar frameworks, a built-in support for high performance should be provided and enforced transparently, especially in parallel simulations. The paper presents solutions developed to effectively tackle these and other more specific problems (data handling and storage, implementation of physical models and numerical methods that have arisen in the development of COOLFluiD, an environment for PDE solvers. Particular attention is devoted to describe a data storage facility, highly suitable for both serial and parallel computing, and to discuss the application of two design patterns, Perspective and Method-Command-Strategy, that support extensibility and run-time flexibility in the implementation of physical models and generic numerical algorithms respectively.

  12. School lunch and snacking patterns among high school students: associations with school food environment and policies.

    Science.gov (United States)

    Neumark-Sztainer, Dianne; French, Simone A; Hannan, Peter J; Story, Mary; Fulkerson, Jayne A

    2005-10-06

    This study examined associations between high school students' lunch patterns and vending machine purchases and the school food environment and policies. A randomly selected sample of 1088 high school students from 20 schools completed surveys about their lunch practices and vending machine purchases. School food policies were assessed by principal and food director surveys. The number of vending machines and their hours of operation were assessed by trained research staff. Students at schools with open campus policies during lunchtime were significantly more likely to eat lunch at a fast food restaurant than students at schools with closed campus policies (0.7 days/week vs. 0.2 days/week, p off during lunch time, students purchased soft drinks from vending machines 1.4 +/- 1.6 days/week as compared to 1.9 +/- 1.8 days/week in schools in which soft drink machines were turned on during lunch (p = .040). School food policies that decrease access to foods high in fats and sugars are associated with less frequent purchase of these items in school among high school students. Schools should examine their food-related policies and decrease access to foods that are low in nutrients and high in fats and sugars.

  13. School lunch and snacking patterns among high school students: Associations with school food environment and policies

    Directory of Open Access Journals (Sweden)

    Story Mary

    2005-10-01

    Full Text Available Abstract Objectives This study examined associations between high school students' lunch patterns and vending machine purchases and the school food environment and policies. Methods A randomly selected sample of 1088 high school students from 20 schools completed surveys about their lunch practices and vending machine purchases. School food policies were assessed by principal and food director surveys. The number of vending machines and their hours of operation were assessed by trained research staff. Results Students at schools with open campus policies during lunchtime were significantly more likely to eat lunch at a fast food restaurant than students at schools with closed campus policies (0.7 days/week vs. 0.2 days/week, p Conclusion School food policies that decrease access to foods high in fats and sugars are associated with less frequent purchase of these items in school among high school students. Schools should examine their food-related policies and decrease access to foods that are low in nutrients and high in fats and sugars.

  14. Cranial biomechanics underpins high sauropod diversity in resource-poor environments.

    Science.gov (United States)

    Button, David J; Rayfield, Emily J; Barrett, Paul M

    2014-11-22

    High megaherbivore species richness is documented in both fossil and contemporary ecosystems despite their high individual energy requirements. An extreme example of this is the Late Jurassic Morrison Formation, which was dominated by sauropod dinosaurs, the largest known terrestrial vertebrates. High sauropod diversity within the resource-limited Morrison is paradoxical, but might be explicable through sophisticated resource partitioning. This hypothesis was tested through finite-element analysis of the crania of the Morrison taxa Camarasaurus and Diplodocus. Results demonstrate divergent specialization, with Camarasaurus capable of exerting and accommodating greater bite forces than Diplodocus, permitting consumption of harder food items. Analysis of craniodental biomechanical characters taken from 35 sauropod taxa demonstrates a functional dichotomy in terms of bite force, cranial robustness and occlusal relationships yielding two polyphyletic functional 'grades'. Morrison taxa are widely distributed within and between these two morphotypes, reflecting distinctive foraging specializations that formed a biomechanical basis for niche partitioning between them. This partitioning, coupled with benefits associated with large body size, would have enabled the high sauropod diversities present in the Morrison Formation. Further, this provides insight into the mechanisms responsible for supporting the high diversities of large megaherbivores observed in other Mesozoic and Cenozoic communities, particularly those occurring in resource-limited environments.

  15. Rheological Study on ATBS-AM Copolymer-Surfactant System in High-Temperature and High-Salinity Environment

    Directory of Open Access Journals (Sweden)

    Muhammad Shahzad Kamal

    2013-01-01

    Full Text Available Experimental studies were conducted to evaluate the rheological properties of surfactant-polymer (SP system. This SP system consists of a copolymer of acrylamide (AM and acrylamido tertiary butyl sulfonate (ATBS and sodium dodecyl sulphate (SDS surfactant. Effects of surfactant concentration, temperature, polymer concentration, and salinity on rheological properties of SP system were investigated by means of oscillation and shear measurements. Comparison with classical partially hydrolyzed polyacrylamide (HPAM was made. For the same temperature range, the viscosity drop for HPAM was about four times higher than the viscosity drop for ATBS-AM copolymer. In deionized water, viscosity of both polymers and SP systems was very high as compared to viscosity in saline water. Viscosity reduction of ATBS-AM copolymer was higher for salts having divalent cations. The SP system showed precipitation in presence of divalent cations. It worked well with monovalent cations even at relatively high salinities. The addition of 0.1% surfactant to the polymer resulted in a 60% decrease in the viscosity. Some interfacial rheological experiments were also carried out to investigate the behaviors on the interface between SP solutions and oil. Addition of 0.1% surfactant showed a 65% decrease in G′ at SP solution-oil interface. SP system consisting of ATBS-AM and SDS showed better performance at high temperature compared to HPAM-SDS system. Due to precipitation, the SP system should be restricted to environment having low divalent cations.

  16. Meaningful weight loss in obese postmenopausal women: A pilot study of high-intensity interval training and wearable technology.

    Science.gov (United States)

    Grossman, Joan A; Arigo, Danielle; Bachman, Jessica L

    2017-10-30

    Postmenopausal women cite lack of time as their primary barrier to exercise and related weight control behaviors. The purpose of this study was to address this barrier via testing the feasibility and initial outcomes of a short-duration/high-intensity interval training (HIIT)-based weight loss program among obese postmenopausal women, with descriptive comparison to an endurance-focused exercise program. A 16-week behavioral program incorporated (1) HIIT to limit time necessary to produce health benefits of exercise, and (2) wearable activity sensors to facilitate self-monitoring exercise. Participants (n = 11; MAge = 59 ± 5.33; MBMI = 32.0 ± 2.53 kg/m) were randomly assigned to HIIT or endurance exercise. Both groups followed a calorie-restricted diet, attended monthly in-person meetings, weekly weigh-ins and electronic check-ins to review behavioral skills, and monitored their exercise with a Fitbit ChargeHR. Adherence to exercise programs, assessed with the Fitbit sensor, was used to determine feasibility. Participants in the HIIT group (6/6) adhered to their program, whereas 3 of 5 adhered to the Endurance program. Participants in the HIIT group lost twice as much weight as those in the Endurance group (8.7% vs 4.3% of initial body weight), and lost an additional 6 in. of body mass. In addition, only the HIIT group significantly changed fat mass, body mass index, and fat-free mass (Ps weight loss and body composition changes in obese postmenopausal women, and indicate that additional investigation of this approach is warranted to reduce postmenopausal chronic disease risk.

  17. Impact of slurry application method on phosphorus loss in runoff from grassland soils during periods of high soil moisture content

    Directory of Open Access Journals (Sweden)

    McConnell D.A.

    2016-06-01

    Full Text Available Previous studies have reported that the trailing shoe application technique reduces phosphorus (P in the runoff postslurry application when compared to the traditional splash-plate application technique. However, the effectiveness of the trailing-shoe technique as a means of reducing P losses has not been evaluated when slurry is applied during periods of high soil moisture levels and lower herbage covers. To address this issue, three treatments were examined in a 3 × 4 factorial design split-plot experiment, with treatments comprising three slurry treatments: control (no slurry, splashplate and trailing-shoe, and four slurry application dates: 7 December, 18 January, 1 March and 10 April. Dairy cow slurry was applied at a rate of 20 m3/ha, while simulated runoff was generated 2, 9 and 16 days later and analysed for a range of P fractions. Dissolved reactive P concentrations in runoff at day two was 41% lower when slurry was applied using the trailing-shoe technique, compared to the splash-plate technique (P < 0.05. In addition, P concentrations in runoff were higher (P < 0.05 from slurry applied in December and March compared to slurry applied in January or April, coinciding with periods of higher soil moisture contents. While the latter highlights that ‘calendar’-based non-spreading periods might not always achieve the desired consequences, the study demonstrated that further field-scale investigations into the trailing shoe as a mitigation measure to reduced P loss from agricultural soils is warranted.

  18. A new structure of photonic crystal fiber with high sensitivity, high nonlinearity, high birefringence and low confinement loss for liquid analyte sensing applications

    Directory of Open Access Journals (Sweden)

    Md. Faizul Huq Arif

    2017-02-01

    Full Text Available This paper proposes the design and optimization of microstructure optical fiber for liquid sensing applications. A number of propagation characteristics have been compared between two formations of hexagonal cladding of our proposed PCF structure. The core of the proposed PCF structure is designed with two rows of supplementary elliptical air holes. We investigate the performance of the designed PCFs for Ethanol as a liquid sample to be sensed. Numerical analysis is carried out by employing the full vectorial Finite Element Method (FEM to examine the modal birefringence, confinement loss, relative sensitivity and nonlinear coefficient of the proposed PCF structure.

  19. Mutation Analysis of SLC26A4 for Pendred Syndrome and Nonsyndromic Hearing Loss by High-Resolution Melting

    Science.gov (United States)

    Chen, Neng; Tranebjærg, Lisbeth; Rendtorff, Nanna Dahl; Schrijver, Iris

    2011-01-01

    Pendred syndrome and DFNB4 (autosomal recessive nonsyndromic congenital deafness, locus 4) are associated with autosomal recessive congenital sensorineural hearing loss and mutations in the SLC26A4 gene. Extensive allelic heterogeneity, however, necessitates analysis of all exons and splice sites to identify mutations for individual patients. Although Sanger sequencing is the gold standard for mutation detection, screening methods supplemented with targeted sequencing can provide a cost-effective alternative. One such method, denaturing high-performance liquid chromatography, was developed for clinical mutation detection in SLC26A4. However, this method inherently cannot distinguish homozygous changes from wild-type sequences. High-resolution melting (HRM), on the other hand, can detect heterozygous and homozygous changes cost-effectively, without any post-PCR modifications. We developed a closed-tube HRM mutation detection method specific for SLC26A4 that can be used in the clinical diagnostic setting. Twenty-eight primer pairs were designed to cover all 21 SLC26A4 exons and splice junction sequences. Using the resulting amplicons, initial HRM analysis detected all 45 variants previously identified by sequencing. Subsequently, a 384-well plate format was designed for up to three patient samples per run. Blinded HRM testing on these plates of patient samples collected over 1 year in a clinical diagnostic laboratory accurately detected all variants identified by sequencing. In conclusion, HRM with targeted sequencing is a reliable, simple, and cost-effective method for SLC26A4 mutation screening and detection. PMID:21704276

  20. A Modified SDS-Based DNA Extraction Method for High Quality Environmental DNA from Seafloor Environments.

    Science.gov (United States)

    Natarajan, Vengadesh Perumal; Zhang, Xinxu; Morono, Yuki; Inagaki, Fumio; Wang, Fengping

    2016-01-01

    Recovering high quality genomic DNA from environmental samples is a crucial primary step to understand the genetic, metabolic, and evolutionary characteristics of microbial communities through molecular ecological approaches. However, it is often challenging because of the difficulty of effective cell lysis without fragmenting the genomic DNA. This work aims to improve the previous SDS-based DNA extraction methods for high-biomass seafloor samples, such as pelagic sediments and metal sulfide chimney, to obtain high quality and high molecular weight of the genomic DNA applicable for the subsequent molecular ecological analyses. In this regard, we standardized a modified SDS-based DNA extraction method (M-SDS), and its performance was then compared to those extracted by a recently developed hot-alkaline DNA extraction method (HA) and a commercial DNA extraction kit. Consequently, the M-SDS method resulted in higher DNA yield and cell lysis efficiency, lower DNA shearing, and higher diversity scores than other two methods, providing a comprehensive DNA assemblage of the microbial community on the seafloor depositional environment.