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Sample records for noise-equivalent temperature difference

  1. Effects of Cylindrical Chopper Geometry on Calculating Power Coupling Efficiency and Noise Equivalent Temperature Difference

    DTIC Science & Technology

    2011-01-01

    in Teff = 180 K. Instead of observing an effective temperature difference of 218 K between the chopper and cold scene, a 115 K temperature...difference (295 K – Teff ) results for the cylindrical chopper. Depending on the specifics of the setup, including the location of the detector array (L0

  2. Noise Equivalent Power of Graphene-Superconductor-Based Optical Sensor

    NASA Astrophysics Data System (ADS)

    Aghda, B. Afkhami; Moftakharzadeh, A.; Hosseini, M.

    In this paper, the noise equivalent power (NEP) of optical sensors based on graphene-superconductor junctions in the voltage bias operation mode has been calculated. The effects of device parameters such as temperature, magnetic field and device resistance on the NEP of these detectors have been thoroughly investigated. By solving the related equations, graphene specific heat, thermal conductivity, electron-phonon interaction and responsivity of the detector have been obtained. Using the calculated parameters, the NEP of the device was obtained. The results show that at constant magnetic field the NEP will increase linearly by increasing device temperature. On the other hand, at constant temperature the behavior of NEP versus magnetic field is first increasing and then decreasing. Our calculations show that the optimal resistance of the device has a direct relation with respect to the device temperature, while in the investigated operating range the optimal resistance of device is almost independent of the magnetic field.

  3. Equivalence of optical and electrical noise equivalent power of hybrid NbTiN-Al microwave kinetic inductance detectors

    SciTech Connect

    Janssen, R. M. J.; Endo, A.; Visser, P. J. de; Klapwijk, T. M.; Baselmans, J. J. A.

    2014-11-10

    We have measured and compared the response of hybrid NbTiN-Al Microwave Kinetic Inductance Detectors (MKIDs) to changes in bath temperature and illumination by sub-mm radiation. We show that these two stimulants have an equivalent effect on the resonance feature of hybrid MKIDs. We determine an electrical noise equivalent power (NEP) from the measured temperature responsivity, quasiparticle recombination time, superconducting transition temperature, and noise spectrum, all of which can be measured in a dark environment. For the two hybrid NbTiN-Al MKIDs studied in detail, the electrical NEP is within a factor of two of the optical NEP, which is measured directly using a blackbody source.

  4. Measuring PET scanner sensitivity; Relating count rates to image signal-to-noise ratios using noise equivalent counts

    SciTech Connect

    Strother, S.C. ); Casey, M.E. ); Hoffman, E.J. . Nuclear Medicine Lab.)

    1990-04-01

    Sensitivity parameters derived from a plot of a scanner's true coincidence count (TCC) rates as a function of activity in a 20 cm cylindrical phantom have no direct link to image quality. Noise equivalent count (NEC) rate curves, which incorporate the noise effects of subtracting the randoms and scatter count components provide a direct link between image signal-to-noise ratios and the scatter, randoms and trues coincidence count rates. The authors have measured TCC and NEC curves with a standardized 20 cm diameter nylon cylinder for five different PET scanners with several scanner-collimator combinations. In addition, the authors have compared TCC and NEC curves on one scanner with those from an Alderson brain phantom.

  5. Determination of noise equivalent reflectance for a multispectral scanner: A scanner sensitivity study

    NASA Technical Reports Server (NTRS)

    Gibbons, D. E.; Richard, R. R.

    1979-01-01

    The methods used to calculate the sensitivity parameter noise equivalent reflectance of a remote-sensing scanner are explored, and the results are compared with values measured over calibrated test sites. Data were acquired on four occasions covering a span of 4 years and providing various atmospheric conditions. One of the calculated values was based on assumed atmospheric conditions, whereas two others were based on atmospheric models. Results indicate that the assumed atmospheric conditions provide useful answers adequate for many purposes. A nomograph was developed to indicate sensitivity variations due to geographic location, time of day, and season.

  6. A reconsideration of the noise equivalent power and the data analysis procedure for the infrared imaging video bolometers

    SciTech Connect

    Pandya, Shwetang N. Sano, Ryuichi; Peterson, Byron J.; Kobayashi, Masahiro; Mukai, Kiyofumi; Pandya, Santosh P.

    2014-12-15

    The infrared imaging video bolometer (IRVB) used for measurement of the two-dimensional (2D) radiation profiles from the Large Helical Device has been significantly upgraded recently to improve its signal to noise ratio, sensitivity, and calibration, which ultimately provides quantitative measurements of the radiation from the plasma. The reliability of the quantified data needs to be established by various checks. The noise estimates also need to be revised and more realistic values need to be established. It is shown that the 2D heat diffusion equation can be used for estimating the power falling on the IRVB foil, even with a significant amount of spatial variation in the thermal diffusivity across the area of the platinum foil found experimentally during foil calibration. The equation for the noise equivalent power density (NEPD) is re-derived to include the errors in the measurement of the thermophysical and the optical properties of the IRVB foil. The theoretical value estimated using this newly derived equation matches closely, within 5.5%, with the mean experimental value. The change in the contribution of each error term of the NEPD equation with rising foil temperature is also studied and the blackbody term is found to dominate the other terms at elevated operating temperatures. The IRVB foil is also sensitive to the charge exchange (CX) neutrals escaping from the plasma. The CX neutral contribution is estimated to be marginally higher than the noise equivalent power (NEP) of the IRVB. It is also established that the radiation measured by the IRVB originates from the impurity line radiation from the plasma and not from the heated divertor tiles. The change in the power density due to noise reduction measures such as data smoothing and averaging is found to be comparable to the IRVB NEPD. The precautions that need to be considered during background subtraction are also discussed with experimental illustrations. Finally, the analysis algorithm with all the

  7. Asymmetry in the noise equivalent angle performance of the JWST fine guidance sensor

    NASA Astrophysics Data System (ADS)

    Rowlands, Neil; Warner, Gerry; Albert, Loic; Hardy, Tim; Pipher, Judith; Hutchings, John; Doyon, Rene

    2014-07-01

    The James Webb Space Telescope Fine Guidance Sensor makes use of three 2048×2048 five micron cutoff H2RG HgCdTe detectors from Teledyne Imaging Systems. The FGS consists of two Guider channels and a Near-InfraRed Imager and Slitless Spectrograph (NIRISS) channel. We report here on detailed tests results from the Guider channels originating in both instrument level performance testing and from recent Guider performance testing with the FGS integrated into JWST's Integrated Science Instrument Module (ISIM). A key performance parameter is the noise equivalent angle (NEA) or centroiding precision. The JWST requirement flowed down to the Guiders is a NEA of 4 milli-arcseonds, equivalent to approximately 1/20th of a detector pixel. This performance has been achieved in the testing to date. We have noted a systematic asymmetry in the NEA depending on whether the NEA in the row or column direction is considered. This asymmetry depends on guide star brightness and reaches its maximum, where the row NEA is 15% to 20% larger than the column NEA, at the dim end of the Guide star brightness range. We evaluate the detector level characteristics of spatially correlated noise and asymmetric inter-pixel capacitance (IPC) as potential sources of this NEA asymmetry. Modelling is used to estimate the impact on NEA of these potential contributors. These model results are then compared to the Guider test results obtained to date in an effort to isolate the cause of this effect. While asymmetric IPC can induce asymmetric NEA, the required magnitude of IPC is far greater than observed in these detectors. Thus, spatially correlated noise was found to be the most likely cause of the asymmetric NEA.

  8. Characterization of imaging performance in differential phase contrast CT compared with the conventional CT: Spectrum of noise equivalent quanta NEQ(k)

    SciTech Connect

    Tang Xiangyang; Yang Yi; Tang Shaojie

    2012-07-15

    Purpose: Differential phase contrast CT (DPC-CT) is emerging as a new technology to improve the contrast sensitivity of conventional attenuation-based CT. The noise equivalent quanta as a function over spatial frequency, i.e., the spectrum of noise equivalent quanta NEQ(k), is a decisive indicator of the signal and noise transfer properties of an imaging system. In this work, we derive the functional form of NEQ(k) in DPC-CT. Via system modeling, analysis, and computer simulation, we evaluate and verify the derived NEQ(k) and compare it with that of the conventional attenuation-based CT. Methods: The DPC-CT is implemented with x-ray tube and gratings. The x-ray propagation and data acquisition are modeled and simulated through Fresnel and Fourier analysis. A monochromatic x-ray source (30 keV) is assumed to exclude any system imperfection and interference caused by scatter and beam hardening, while a 360 Degree-Sign full scan is carried out in data acquisition to avoid any weighting scheme that may disrupt noise randomness. Adequate upsampling is implemented to simulate the x-ray beam's propagation through the gratings G{sub 1} and G{sub 2} with periods 8 and 4 {mu}m, respectively, while the intergrating distance is 193.6 mm (1/16 of the Talbot distance). The dimensions of the detector cell for data acquisition are 32 Multiplication-Sign 32, 64 Multiplication-Sign 64, 96 Multiplication-Sign 96, and 128 Multiplication-Sign 128 {mu}m{sup 2}, respectively, corresponding to a 40.96 Multiplication-Sign 40.96 mm{sup 2} field of view in data acquisition. An air phantom is employed to obtain the noise power spectrum NPS(k), spectrum of noise equivalent quanta NEQ(k), and detective quantum efficiency DQE(k). A cylindrical water phantom at 5.1 mm diameter and complex refraction coefficient n= 1 -{delta}+i{beta}= 1 -2.5604 Multiplication-Sign 10{sup -7}+i1.2353 Multiplication-Sign 10{sup -10} is placed in air to measure the edge transfer function, line spread function and

  9. Energy from low temperature differences

    NASA Astrophysics Data System (ADS)

    Parsons, B. K.

    1985-05-01

    A number of energy conservation and alternative energy approaches utilize a low temperature heat source. Applications in this category include: solar ponds, ocean thermal energy conversion (OTEC), low temperature solar thermal, geothermal, and waste heat recovery and bottoming cycles. Low temperature power extraction techniques are presented and the differences between closed and open Rankine power cycles are discussed. Specific applications and technical areas of current research in OTEC along with a breakdown of plant operating conditions and a rough cost estimate illustrate how the use of low temperature power conversion technology can be cost effective.

  10. Microclimatic Temperature Relationships over Different Surfaces.

    ERIC Educational Resources Information Center

    Williams, Thomas B.

    1991-01-01

    Describes a study of temperature variations over different surfaces in an urban campus setting. Explains that researchers sampled temperatures over grass, bare soil, gravel, concrete, and blacktop. Reports that grassy areas registered the highest morning temperatures and lowest afternoon temperatures. (SG)

  11. Electron temperature differences and double layers

    NASA Technical Reports Server (NTRS)

    Chan, C.; Hershkowitz, N.; Lonngren, K. E.

    1983-01-01

    Electron temperature differences across plasma double layers are studied experimentally. It is shown that the temperature differences across a double layer can be varied and are not a result of thermalization of the bump-on-tail distribution. The implications of these results for electron thermal energy transport in laser-pellet and tandem-mirror experiments are also discussed.

  12. Application of the noise power spectrum in modern diagnostic MDCT: part I. Measurement of noise power spectra and noise equivalent quanta.

    PubMed

    Boedeker, K L; Cooper, V N; McNitt-Gray, M F

    2007-07-21

    Dose reduction efforts in diagnostic CT have brought the tradeoff of dose versus image quality to the forefront. The need for meaningful characterization of image noise beyond that offered by pixel standard deviation is becoming increasingly important. This work aims to study the implementation of the noise power spectrum (NPS) and noise equivalent quanta (NEQ) on modern, multislice diagnostic CT scanners. The details of NPS and NEQ measurement are outlined and special attention is paid to issues unique to multislice CT. Aliasing, filter design and effects of acquisition geometry are investigated. While it was found that both metrics can be implemented in modern CT, it was discovered that NEQ cannot be aptly applied with certain non-traditional reconstruction filters or in helical mode. NPS and NEQ under a variety of conditions are examined. Extensions of NPS and NEQ to uses in protocol standardization are also discussed.

  13. Measuring noise equivalent irradiance of a digital short-wave infrared imaging system using a broadband source to simulate the night spectrum

    NASA Astrophysics Data System (ADS)

    Green, John R.; Robinson, Timothy

    2015-05-01

    There is a growing interest in developing helmet-mounted digital imaging systems (HMDIS) for integration into military aircraft cockpits. This interest stems from the multiple advantages of digital vs. analog imaging such as image fusion from multiple sensors, data processing to enhance the image contrast, superposition of non-imaging data over the image, and sending images to remote location for analysis. There are several properties an HMDIS must have in order to aid the pilot during night operations. In addition to the resolution, image refresh rate, dynamic range, and sensor uniformity over the entire Focal Plane Array (FPA); the imaging system must have the sensitivity to detect the limited night light available filtered through cockpit transparencies. Digital sensor sensitivity is generally measured monochromatically using a laser with a wavelength near the peak detector quantum efficiency, and is generally reported as either the Noise Equivalent Power (NEP) or Noise Equivalent Irradiance (NEI). This paper proposes a test system that measures NEI of Short-Wave Infrared (SWIR) digital imaging systems using a broadband source that simulates the night spectrum. This method has a few advantages over a monochromatic method. Namely, the test conditions provide spectrum closer to what is experienced by the end-user, and the resulting NEI may be compared directly to modeled night glow irradiance calculation. This comparison may be used to assess the Technology Readiness Level of the imaging system for the application. The test system is being developed under a Cooperative Research and Development Agreement (CRADA) with the Air Force Research Laboratory.

  14. Component analysis of a new Solid State X-ray Image Intensifier (SSXII) using photon transfer and Instrumentation Noise Equivalent Exposure (INEE) measurements.

    PubMed

    Kuhls-Gilcrist, Andrew; Bednarek, Daniel R; Rudin, Stephen

    2009-01-01

    The SSXII is a novel x-ray imager designed to improve upon the performance limitations of conventional dynamic radiographic/fluoroscopic imagers related to resolution, charge-trapping, frame-rate, and instrumentation-noise. The SSXII consists of a CsI:Tl phosphor coupled via a fiber-optic taper (FOT) to an electron-multiplying CCD (EMCCD). To facilitate investigational studies, initial designs enable interchangeability of such imaging components. Measurements of various component and configuration characteristics enable an optimization analysis with respect to overall detector performance. Photon transfer was used to characterize the EMCCD performance including ADC sensitivity, read-noise, full-well capacity and quantum efficiency. X-ray sensitivity was measured using RQA x-ray spectra. Imaging components were analyzed in terms of their MTF and transmission efficiency. The EMCCD was measured to have a very low effective read-noise of less than 1 electron rms at modest EMCCD gains, which is more than two orders-of-magnitude less than flat panel (FPD) and CMOS-based detectors. The variable signal amplification from 1 to 2000 times enables selectable sensitivities ranging from 8.5 (168) to over 15k (300k) electrons per incident x-ray photon with (without) a 4:1 FOT; these sensitivities could be readily increased with further component optimization. MTF and DQE measurements indicate the SSXII performance is comparable to current state-of-the-art detectors at low spatial frequencies and far exceeds them at higher spatial frequencies. The instrumentation noise equivalent exposure (INEE) was measured to be less than 0.3 μR out to 10 cycles/mm, which is substantially better than FPDs. Component analysis suggests that these improvements can be substantially increased with further detector optimization.

  15. Component analysis of a new solid state x-ray image intensifier (SSXII) using photon transfer and instrumentation noise equivalent exposure (INEE) measurements

    NASA Astrophysics Data System (ADS)

    Kuhls-Gilcrist, Andrew; Bednarek, Daniel R.; Rudin, Stephen

    2009-02-01

    The SSXII is a novel x-ray imager designed to improve upon the performance limitations of conventional dynamic radiographic/fluoroscopic imagers related to resolution, charge-trapping, frame-rate, and instrumentation-noise. The SSXII consists of a CsI:Tl phosphor coupled via a fiber-optic taper (FOT) to an electron-multiplying CCD (EMCCD). To facilitate investigational studies, initial designs enable interchangeability of such imaging components. Measurements of various component and configuration characteristics enable an optimization analysis with respect to overall detector performance. Photon transfer was used to characterize the EMCCD performance including ADC sensitivity, read-noise, full-well capacity and quantum efficiency. X-ray sensitivity was measured using RQA x-ray spectra. Imaging components were analyzed in terms of their MTF and transmission efficiency. The EMCCD was measured to have a very low effective read-noise of less than 1 electron rms at modest EMCCD gains, which is more than two orders-ofmagnitude less than flat panel (FPD) and CMOS-based detectors. The variable signal amplification from 1 to 2000 times enables selectable sensitivities ranging from 8.5 (168) to over 15k (300k) electrons per incident x-ray photon with (without) a 4:1 FOT; these sensitivities could be readily increased with further component optimization. MTF and DQE measurements indicate the SSXII performance is comparable to current state-of-the-art detectors at low spatial frequencies and far exceeds them at higher spatial frequencies. The instrumentation noise equivalent exposure (INEE) was measured to be less than 0.3 μR out to 10 cycles/mm, which is substantially better than FPDs. Component analysis suggests that these improvements can be substantially increased with further detector optimization.

  16. Myoglobin solvent structure at different temperatures

    SciTech Connect

    Daniels, B.V.; Korszun, Z.R.; Schoenborn, B.P.

    1994-12-31

    The structure of the solvent surrounding myoglobin crystals has been analyzed using neutron diffraction data, and the results indicate that the water around the protein is not disordered, but rather lies in well-defined hydration shells. We have analyzed the structure of the solvent surrounding the protein by collecting neutron diffraction data at four different temperatures, namely, 80, 130, 180, and 240K. Relative Wilson Statistics applied to low resolution data showed evidence of a phase transition in the region of 180K. A plot of the liquidity factor, B{sub sn}, versus distance from the protein surface begins with a high plateau near the surface of the protein and drops to two minima at distances from the protein surface of about 2.35{Angstrom} and 3.85{Angstrom}. Two distinct hydration shells are observed. Both hydration shells are observed to expand as the temperature is increased.

  17. Meaning of temperature in different thermostatistical ensembles.

    PubMed

    Hänggi, Peter; Hilbert, Stefan; Dunkel, Jörn

    2016-03-28

    Depending on the exact experimental conditions, the thermodynamic properties of physical systems can be related to one or more thermostatistical ensembles. Here, we survey the notion of thermodynamic temperature in different statistical ensembles, focusing in particular on subtleties that arise when ensembles become non-equivalent. The 'mother' of all ensembles, the microcanonical ensemble, uses entropy and internal energy (the most fundamental, dynamically conserved quantity) to derive temperature as a secondary thermodynamic variable. Over the past century, some confusion has been caused by the fact that several competing microcanonical entropy definitions are used in the literature, most commonly the volume and surface entropies introduced by Gibbs. It can be proved, however, that only the volume entropy satisfies exactly the traditional form of the laws of thermodynamics for a broad class of physical systems, including all standard classical Hamiltonian systems, regardless of their size. This mathematically rigorous fact implies that negative 'absolute' temperatures and Carnot efficiencies more than 1 are not achievable within a standard thermodynamical framework. As an important offspring of microcanonical thermostatistics, we shall briefly consider the canonical ensemble and comment on the validity of the Boltzmann weight factor. We conclude by addressing open mathematical problems that arise for systems with discrete energy spectra.

  18. Radically Different Kinetics at Low Temperatures

    NASA Astrophysics Data System (ADS)

    Sims, Ian

    2014-06-01

    The use of the CRESU (Cinétique de Réaction en Ecoulement Supersonique Uniforme, or Reaction Kinetics in Uniform Supersonic Flow) technique coupled with pulsed laser photochemical kinetics methods has shown that reactions involving radicals can be very rapid at temperatures down to 10 K or below. The results have had a major impact in astrochemistry and planetology, as well as proving an exacting test for theory. The technique has also been applied to the formation of transient complexes of interest both in atmospheric chemistry and combustion. Until now, all of the chemical reactions studied in this way have taken place on attractive potential energy surfaces with no overall barrier to reaction. The F + H2 {→} HF + H reaction does possess a substantial energetic barrier ({\\cong} 800 K), and might therefore be expected to slow to a negligible rate at very low temperatures. In fact, this H-atom abstraction reaction does take place efficiently at low temperatures due entirely to tunneling. I will report direct experimental measurements of the rate of this reaction down to a temperature of 11 K, in remarkable agreement with state-of-the-art quantum reactive scattering calculations by François Lique (Université du Havre) and Millard Alexander (University of Maryland). It is thought that long chain cyanopolyyne molecules H(C2)nCN may play an important role in the formation of the orange haze layer in Titan's atmosphere. The longest carbon chain molecule observed in interstellar space, HC11N, is also a member of this series. I will present new results, obtained in collaboration with Jean-Claude Guillemin (Ecole de Chimie de Rennes) and Stephen Klippenstein (Argonne National Labs), on reactions of C2H, CN and C3N radicals (using a new LIF scheme by Hoshina and Endo which contribute to the low temperature formation of (cyano)polyynes. H. Sabbah, L. Biennier, I. R. Sims, Y. Georgievskii, S. J. Klippenstein, I. W. M. Smith, Science 317, 102 (2007). S. D. Le Picard, M

  19. Mid-infrared laser absorption spectrometers based upon all-diode laser difference frequency generation and a room temperature quantum cascade laser for the detection of CO, N2O and NO

    NASA Astrophysics Data System (ADS)

    Kasyutich, V. L.; Holdsworth, R. J.; Martin, P. A.

    2008-08-01

    We describe the performance of two mid-infrared laser spectrometers for carbon monoxide, nitrous oxide and nitric oxide detection. The first spectrometer for CO and N2O detection around 2203 cm-1 is based upon all-diode laser difference frequency generation (DFG) in a quasi-phase matched periodically-poled lithium niobate (PPLN) crystal using two continuous-wave room-temperature distributed feedback diode lasers at 859 and 1059 nm. We also report on the performance of a mid-infrared spectrometer for NO detection at ˜ 1900 cm-1 based upon a thermoelectrically-cooled continuous-wave distributed feedback quantum cascade laser (QCL). Both spectrometers had a single-pass optical cell and a thermoelectrically cooled HgCdZnTe photovoltaic detector. Typical minimum detection limits of 2.8 ppmv for CO, 0.6 ppmv for N2O and 2.7 ppmv for NO have been demonstrated for a 100 averaged spectra acquired within 1.25 s and a cell base length of 21 cm at ˜ 100 Torr. Noise-equivalent absorptions of 10-5 and 10-4 Hz-1/2 are typically demonstrated for the QCL and the DFG based spectrometers, respectively.

  20. Ground surface temperature simulation for different land covers

    NASA Astrophysics Data System (ADS)

    Herb, William R.; Janke, Ben; Mohseni, Omid; Stefan, Heinz G.

    2008-07-01

    SummaryA model for predicting temperature time series for dry and wet land surfaces is described, as part of a larger project to assess the impact of urban development on the temperature of surface runoff and coldwater streams. Surface heat transfer processes on impervious and pervious land surfaces were investigated for both dry and wet weather periods. The surface heat transfer equations were combined with a numerical approximation of the 1-D unsteady heat diffusion equation to calculate pavement and soil temperature profiles to a depth of 10 m. Equations to predict the magnitude of the radiative, convective, conductive and evaporative heat fluxes at a dry or wet surface, using standard climate data as input, were developed. A model for the effect of plant canopies on surface heat transfer was included for vegetated land surfaces. Given suitable climate data, the model can simulate the land surface and sub-surface temperatures continuously throughout a six month time period or for a single rainfall event. Land surface temperatures have been successfully simulated for pavements, bare soil, short and tall grass, a forest, and two agricultural crops (corn and soybeans). The simulations were run for three different locations in US, and different years as imposed by the availability of measured soil temperature and climate data. To clarify the effect of land use on surface temperatures, the calibrated coefficients for each land use and the same soil coefficients were used to simulate surface temperatures for a six year climate data set from Albertville, MN. Asphalt and concrete give the highest surface temperatures, as expected, while vegetated surfaces gave the lowest. Bare soil gives surface temperatures that lie between those for pavements and plant-covered surfaces. The soil temperature model predicts hourly surface temperatures of bare soil and pavement with root-mean-square errors (RMSEs) of 1-2 °C, and hourly surface temperatures of vegetation-covered surfaces

  1. ATMOSPHERIC CIRCULATION OF HOT JUPITERS: DAYSIDE–NIGHTSIDE TEMPERATURE DIFFERENCES

    SciTech Connect

    Komacek, Thaddeus D.; Showman, Adam P.

    2016-04-10

    The full-phase infrared light curves of low-eccentricity hot Jupiters show a trend of increasing dayside-to-nightside brightness temperature difference with increasing equilibrium temperature. Here, we present a three-dimensional model that explains this relationship, in order to provide insight into the processes that control heat redistribution in tidally locked planetary atmospheres. This three-dimensional model combines predictive analytic theory for the atmospheric circulation and dayside–nightside temperature differences over a range of equilibrium temperatures, atmospheric compositions, and potential frictional drag strengths with numerical solutions of the circulation that verify this analytic theory. The theory shows that the longitudinal propagation of waves mediates dayside–nightside temperature differences in hot Jupiter atmospheres, analogous to the wave adjustment mechanism that regulates the thermal structure in Earth’s tropics. These waves can be damped in hot Jupiter atmospheres by either radiative cooling or potential frictional drag. This frictional drag would likely be caused by Lorentz forces in a partially ionized atmosphere threaded by a background magnetic field, and would increase in strength with increasing temperature. Additionally, the amplitude of radiative heating and cooling increases with increasing temperature, and hence both radiative heating/cooling and frictional drag damp waves more efficiently with increasing equilibrium temperature. Radiative heating and cooling play the largest role in controlling dayside–nightside temperature differences in both our analytic theory and numerical simulations, with frictional drag only being important if it is stronger than the Coriolis force. As a result, dayside–nightside temperature differences in hot Jupiter atmospheres increase with increasing stellar irradiation and decrease with increasing pressure.

  2. Atmospheric Circulation of Hot Jupiters: Dayside-Nightside Temperature Differences

    NASA Astrophysics Data System (ADS)

    Komacek, Thaddeus D.; Showman, Adam P.

    2016-04-01

    The full-phase infrared light curves of low-eccentricity hot Jupiters show a trend of increasing dayside-to-nightside brightness temperature difference with increasing equilibrium temperature. Here, we present a three-dimensional model that explains this relationship, in order to provide insight into the processes that control heat redistribution in tidally locked planetary atmospheres. This three-dimensional model combines predictive analytic theory for the atmospheric circulation and dayside-nightside temperature differences over a range of equilibrium temperatures, atmospheric compositions, and potential frictional drag strengths with numerical solutions of the circulation that verify this analytic theory. The theory shows that the longitudinal propagation of waves mediates dayside-nightside temperature differences in hot Jupiter atmospheres, analogous to the wave adjustment mechanism that regulates the thermal structure in Earth’s tropics. These waves can be damped in hot Jupiter atmospheres by either radiative cooling or potential frictional drag. This frictional drag would likely be caused by Lorentz forces in a partially ionized atmosphere threaded by a background magnetic field, and would increase in strength with increasing temperature. Additionally, the amplitude of radiative heating and cooling increases with increasing temperature, and hence both radiative heating/cooling and frictional drag damp waves more efficiently with increasing equilibrium temperature. Radiative heating and cooling play the largest role in controlling dayside-nightside temperature differences in both our analytic theory and numerical simulations, with frictional drag only being important if it is stronger than the Coriolis force. As a result, dayside-nightside temperature differences in hot Jupiter atmospheres increase with increasing stellar irradiation and decrease with increasing pressure.

  3. Local temperature differences in relation to weather parameters

    NASA Astrophysics Data System (ADS)

    Bogren, J.; Gustavsson, T.; Postgård, U.

    2000-02-01

    The objective of this paper is to focus on the influence of clouds and wind on air and road surface temperature variations between different types of local climate environments. The study area covers 160×130 km2 and includes 35 field stations in the Swedish Road Weather Information System (RWIS) and two synoptic weather stations. By combining data from the two sources, the spatial and temporal variations in air and road surface temperature have been analysed. In the first part of this paper the theoretical influence of different weather parameters is determined. In the empirical part of the study, a validation of the theoretical result is assessed using temperature and weather data from the study area. The results show that it is possible to calculate the temperature variations in relation to topographical siting and different weather factors. During day-time conditions, the effect of screening from the sun has a significant influence on the road surface temperature, even with cloudiness amounting to 4-6 octas, provided that the solar elevation is high. During night-time, the potential for pooling of cold air is determined by cloud cover and wind speed. When cloudy situations prevail during night-time, neutral stability is dominant resulting in a decrease with increasing altitude for both air and surface temperatures. Road surface temperatures, however, have a lower correlation with altitude than air temperature. The variation in surface temperature decreases with altitude is also larger and has a more even distribution than the air temperature decrease with altitude. Wind speed was not an important factor for the variation in surface temperature decrease with altitude, but insolation from the sun during day-time is one parameter to consider.

  4. Temperature transport in Lysimeters – comparison of different setups

    NASA Astrophysics Data System (ADS)

    Weller, Ulrich; Weber, Katja; Seyfarth, Manfred; Reth, Sascha

    2015-04-01

    Lysimeter studies are designed to mimick the undisturbed soil for the study of soil processes. Ecological and chemical processes are influenced by temperature and therefore it is mandatory that the temperature regime in the lysimeter follows closely the natural conditions. Unfortunately the lysimeter has a lower boundary that cuts off the natural dampening temperature flux. Also the walls of the vessel can transport temperature in a higher rate than the soil would do. And the exchange with the surrounding air at the installation facility may add a bias to the temperature regime in the lysimeter vessels. To test the influence of the wall and the lower boundary we have set up a lysimeter experiment with three different lysimeters. These are all 1m² surface by 2 m depth vessels, identically filled with a sandy loam. All three were instrumented with temperature sensors in 4 depths, and at each depth with 4 sensors, with a distance of 2,5 cm; 5 cm; 10 cm and 15 cm from the wall. In addition, temperature sensors in the surrounding soil and air temperature in the lysimeter containment are available. The three vessels differ in their setup and material. One vessel is a standard stainless steel vessel with seepage boundary, the second is stainless steel with isolation and a controlled lower boundary. This vessel has a tube system at the bottom that circulates water in the vessel and the surrounding soil at the same depth. The control ascertains that the bottom temperature of the lysimeter vessel is always the same as in the surrounding soil. The third vessel is made of PE, in order to minimize temperature transport in the wall material. The data so far shows little difference between the alternative setup. It seems that in a well closed lysimeter containment the temperature regime is sufficiently close to the natural soil. This is especially true for the top soil where most biological and chemical processes occur.

  5. Temperature Rise during Resin Composite Polymerization under Different Ceramic Restorations

    PubMed Central

    Yondem, Isa; Altintas, Subutay Han; Usumez, Aslihan

    2011-01-01

    Objectives: The purpose of this study was to measure temperature increase induced by various light polymerizing units during resin composite polymerization beneath one of three types of ceramic restorations. Methods: The resin composite (Variolink II) was polymerized between one of three different ceramic specimens (zirconium oxide, lithium disilicate, feldspathic) (diameter 5 mm, height 2 mm) and a dentin disc (diameter 5 mm, height 1 mm) with a conventional halogen light, a high intensity halogen light, or an LED unit. The temperature rise was measured under the dentin disc with a J-type thermocouple wire connected to a data logger. Ten measurements were carried out for each group. The difference between the initial and highest temperature readings was taken and the 10 calculated temperature changes were averaged to determine the mean value in temperature rise. Two way analysis of variance (ANOVA) was used to analyze the data (polymerizing unit, ceramic brand) for significant differences. The Tukey HSD test was used to perform multiple comparisons (α=.05). Results: Temperature rise did not vary significantly depending on the light polymerizing unit used (P=.16), however, the type of ceramic system showed a significant effect on temperature increases (P<.01). There were no statistically significant differences between lithium disilicate and feldspathic ceramic systems (P >.05); in comparison, the resin composite polymerized under the zirconium oxide ceramic system induced a significantly lower temperature increase than the other ceramic systems tested (P<.05) Conclusions: The resin composite polymerized beneath zirconium oxide ceramic system induced significantly smaller temperature changes. The maximal temperature increase detected in all groups in this study was not viewed as critical for pulpal health. PMID:21769272

  6. Dayside-Nightside Temperature Differences in Hot Jupiter Atmospheres

    NASA Astrophysics Data System (ADS)

    Komacek, Thaddeus D.; Showman, Adam P.

    2015-12-01

    The infrared phase curves of low-eccentricity transiting hot Jupiters show a trend of increasing flux amplitude, or increasing day-night temperature difference, with increasing equilibrium temperature. Here we utilize atmospheric circulation modeling and analytic theory to understand this trend, and the more general question: what processes control heat redistribution in tidally-locked giant planet atmospheres? We performed a wide range of 3D numerical simulations of the atmospheric circulation with simplified forcing, and constructed an analytic theory that explains the day-night temperature differences in these simulations over a wide parameter space. Our analytic theory shows that day-night temperature differences in tidally-locked planet atmospheres are mediated by wave propagation. If planetary-scale waves are free to propagate longitudinally, they will efficiently flatten isentropes and lessen day-night temperature differences. If these waves are damped, the day-night temperature differences will necessarily be larger. We expect that wave propagation in hot Jupiter atmospheres can be damped in two ways: by either radiative cooling or frictional drag. Both of these processes increase in efficacy with increasing equilibrium temperature, as radiative cooling is directly related to the cube of temperature and magnetically-induced (Lorentz) drag becomes stronger with increasing partial ionization and hence temperature. We find that radiative cooling plays the largest role in damping wave propagation and hence plays the biggest role in controlling day-night temperature differences. As a result, day-night temperature differences in hot Jupiter atmospheres decrease with increasing pressure and increase with increasing stellar flux. One can apply this result to phase curve observations of individual hot Jupiters in multiple bandpasses, as varying flux amplitudes between wavelengths implies that different photospheric pressure levels are being probed. Namely, a larger

  7. Simulation of soil temperature dynamics with models using different concepts.

    PubMed

    Sándor, Renáta; Fodor, Nándor

    2012-01-01

    This paper presents two soil temperature models with empirical and mechanistic concepts. At the test site (calcaric arenosol), meteorological parameters as well as soil moisture content and temperature at 5 different depths were measured in an experiment with 8 parcels realizing the combinations of the fertilized, nonfertilized, irrigated, nonirrigated treatments in two replicates. Leaf area dynamics was also monitored. Soil temperature was calculated with the original and a modified version of CERES as well as with the HYDRUS-1D model. The simulated soil temperature values were compared to the observed ones. The vegetation reduced both the average soil temperature and its diurnal amplitude; therefore, considering the leaf area dynamics is important in modeling. The models underestimated the actual soil temperature and overestimated the temperature oscillation within the winter period. All models failed to account for the insulation effect of snow cover. The modified CERES provided explicitly more accurate soil temperature values than the original one. Though HYDRUS-1D provided more accurate soil temperature estimations, its superiority to CERES is not unequivocal as it requires more detailed inputs.

  8. A comparison of the temperature difference according to the placement of a nasopharyngeal temperature probe

    PubMed Central

    Lim, Hyungsun; Kim, Boram; Kim, Dong-Chan; Lee, Sang-Kyi

    2016-01-01

    Background The purpose of this study was to compare temperatures measured at three different sites where a nasopharyngeal temperature probe is commonly placed. Methods Eighty elective abdominal surgical patients were enrolled. After anesthesia induction, four temperature probes were placed at the nasal cavity, upper portion of the nasopharynx, oropharynx, and the esophagus. The placement of the nasopharyngeal temperature probes was evaluated using a flexible nasendoscope, and the depth from the nares was measured. The four temperatures were simultaneously recorded at 10-minute intervals for 60 minutes. Results The average depths of the probes that were placed in the nasal cavity, upper nasopharynx, and the oropharynx were respectively 5.7 ± 0.9 cm, 9.9 ± 0.7 cm, and 13.6 ± 1.7 cm from the nares. In the baseline temperatures, the temperature differences were significantly greater in the nasal cavity 0.32 (95% CI; 0.27-0.37)℃ than in the nasopharynx 0.02 (0.01–0.04)℃, and oropharynx 0.02 (−0.01 to 0.05)℃ compared with the esophagus (P < 0.001). These differences were maintained for 60 minutes. Twenty patients showed a 0.5℃ or greater temperature difference between the nasal cavity and the esophagus, but no patient showed such a difference at the nasopharynx and oropharynx. Conclusions During general anesthesia, the temperatures measured at the upper nasopharynx and the oropharynx, but not the nasal cavity, reflected the core temperature. Therefore, the authors recommend that a probe should be placed at the nasopharynx (≈ 10 cm) or oropharynx (≈ 14 cm) with mucosal attachment for accurate core temperature measurement. PMID:27482312

  9. The temperature difference across the cool skin of the ocean

    NASA Astrophysics Data System (ADS)

    Paulson, C. A.; Simpson, J. J.

    1981-11-01

    The temperature difference ΔT across the cool skin of the ocean was determined from radiometric measurements of surface brightness temperature and conventional measurements of temperature at a depth of 1 m. Eleven days of measurements were made from the R/P Flip in February 1974 about 800 miles north of Hawaii (35°N, 155°W). The surface brightness temperature was corrected for nonblackness of the surface to obtain an estimate of the true surface temperature. The constant λ in Saunders' (1967a) formula, ΔT = λvQ/kU* was found to be λ = 6.5±0.6, where v is kinematic viscosity, Q the upward heat flux just below, the interface, k the thermal conductivity, and U* the friction velocity. The constant is independent of wind speed for winds ranging from 3 to 11 m/s. The use of subsurface rather than surface temperature in the bulk aerodynamic formulas results in an increase in the sum of the sensible and latent heat fluxes equal to 4-5% of Q. However, the percentage change in sensible and latent heat fluxes may be much greater. Spectra of surface and subsurface sea temperature exhibit a peak at low frequencies and fall off approximately proportional to ƒ-3/2; with increasing frequency ƒ. The variability of sea surface temperature was caused about equally by the variability of subsurface temperature and the variability of ΔT. Caution should therefore be exercised in the interpretation of radiometric surface temperature measurements as representative of subsurface temperature.

  10. Regional differences in temperature sensation and thermal comfort in humans.

    PubMed

    Nakamura, Mayumi; Yoda, Tamae; Crawshaw, Larry I; Yasuhara, Saki; Saito, Yasuyo; Kasuga, Momoko; Nagashima, Kei; Kanosue, Kazuyuki

    2008-12-01

    Sensations evoked by thermal stimulation (temperature-related sensations) can be divided into two categories, "temperature sensation" and "thermal comfort." Although several studies have investigated regional differences in temperature sensation, less is known about the sensitivity differences in thermal comfort for the various body regions. In the present study, we examined regional differences in temperature-related sensations with special attention to thermal comfort. Healthy male subjects sitting in an environment of mild heat or cold were locally cooled or warmed with water-perfused stimulators. Areas stimulated were the face, chest, abdomen, and thigh. Temperature sensation and thermal comfort of the stimulated areas were reported by the subjects, as was whole body thermal comfort. During mild heat exposure, facial cooling was most comfortable and facial warming was most uncomfortable. On the other hand, during mild cold exposure, neither warming nor cooling of the face had a major effect. The chest and abdomen had characteristics opposite to those of the face. Local warming of the chest and abdomen did produce a strong comfort sensation during whole body cold exposure. The thermal comfort seen in this study suggests that if given the chance, humans would preferentially cool the head in the heat, and they would maintain the warmth of the trunk areas in the cold. The qualitative differences seen in thermal comfort for the various areas cannot be explained solely by the density or properties of the peripheral thermal receptors and thus must reflect processing mechanisms in the central nervous system.

  11. Development of Dermanyssus gallinae (Acari: Dermanyssidae) at different temperatures.

    PubMed

    Tucci, E C; Prado, A P; Araújo, R P

    2008-08-01

    The development, viability, and life cycle parameters of Dermanyssus gallinae at five different temperatures (15, 20, 25, 30 and 35 degrees C), and at relative humidity 70-85% were evaluated. Life cycle duration was 690.75 h (28 days) at 15 degrees C, 263.12h (11 days) at 20 degrees C, 164.63 h (7 days) at 25 degrees C, 140.69 h (6 days) at 30 degrees C and 172.04 h (7 days) at 35 degrees C. The optimal development temperature for D. gallinae was 30 degrees C, with the greatest survival in all stages and the shortest development time. High mortality at 35 degrees C indicated that this temperature had adverse effects on development of D. gallinae, and that in field conditions D. gallinae populations may decrease or even disappear due to the negative impact of high temperature on development. There were no significant differences in the pre-oviposition period among the four temperatures 20-35 degrees C, indicating that temperature did not affect this part of the life cycle.

  12. Dayside-Nightside Temperature Differences in Hot Jupiter Atmospheres

    NASA Astrophysics Data System (ADS)

    Komacek, T. D.; Showman, A. P.

    2015-12-01

    The full-phase light curves of individual close-in extrasolar giant planets, or "hot Jupiters," show a trend of increasing fractional amplitude with increasing planetary equilibrium temperature. The attached figure shows this trend for 7 transiting low-eccentricity hot Jupiters. For these planets, this trend can be realized as a trend of increasing dayside-to-nightside temperature difference with increasing equilibrium temperature, as these planets are expected to be tidally locked. Here we examine this trend, in order to shed insight on the physical processes that regulate heat redistribution in tidally-locked planet atmospheres. We utilize a combination of analytic theory to predict how heat is redistributed from day to night over a range of equilibrium temperature, atmospheric composition, and potential frictional drag strengths, and confirm the theory using numerical circulation modeling. Our theory identifies that the transition from low to high day-night temperature differences is mediated by wave adjustment, the same process that regulates heat redistribution in the tropics of Earth. Due to their low rotation rate and hence large Rossby deformation radius, tidally locked planets allow for wave propagation to occur over a much larger latitude range than on Earth. Hence, wave adjustment processes play a key role in the the global, not just equatorial, heat redistribution in hot Jupiter atmospheres. Wave propagation can be damped in hot Jupiter atmospheres by either radiative cooling to space or potential frictional drag. This frictional drag, if present, would likely be caused by Lorentz forces in a partially ionized atmosphere threaded by a planetary-scale magnetic field. The radiative cooling timescale is inversely related to the cube of temperature, and any Lorentz drag would increase with temperature due to the increasing ionization fraction of the atmosphere. Hence, both of these processes damp waves more effectively as equilibrium temperature increases

  13. Different annealing temperature suitable for different Mg doped P-GaN

    NASA Astrophysics Data System (ADS)

    Liu, S. T.; Yang, J.; Zhao, D. G.; Jiang, D. S.; Liang, F.; Chen, P.; Zhu, J. J.; Liu, Z. S.; Li, X.; Liu, W.; Zhang, L. Q.; Long, H.; Li, M.

    2017-04-01

    In this work, epitaxial GaN with different Mg doping concentration annealed at different temperature is investigated. Through Hall and PL spectra measurement we found that when Mg doping concentration is different, different annealing temperature is needed for obtaining the best p-type conduction of GaN, and this difference comes from the different influence of annealing on compensated donors. For ultra-heavily Mg doped sample, the process of Mg related donors transferring to non-radiative recombination centers is dominated, so the performance of P-GaN deteriorates with temperature increase. But for low Mg doped sample, the process of Mg related donors transfer to non-raditive recombination is weak compare to the Mg acceptor activation, so along the annealing temperature increase the performance GaN gets better.

  14. Normalized Temperature Contrast Processing in Flash Infrared Thermography

    NASA Technical Reports Server (NTRS)

    Koshti, Ajay M.

    2016-01-01

    The paper presents further development in normalized contrast processing of flash infrared thermography method by the author given in US 8,577,120 B1. The method of computing normalized image or pixel intensity contrast, and normalized temperature contrast are provided, including converting one from the other. Methods of assessing emissivity of the object, afterglow heat flux, reflection temperature change and temperature video imaging during flash thermography are provided. Temperature imaging and normalized temperature contrast imaging provide certain advantages over pixel intensity normalized contrast processing by reducing effect of reflected energy in images and measurements, providing better quantitative data. The subject matter for this paper mostly comes from US 9,066,028 B1 by the author. Examples of normalized image processing video images and normalized temperature processing video images are provided. Examples of surface temperature video images, surface temperature rise video images and simple contrast video images area also provided. Temperature video imaging in flash infrared thermography allows better comparison with flash thermography simulation using commercial software which provides temperature video as the output. Temperature imaging also allows easy comparison of surface temperature change to camera temperature sensitivity or noise equivalent temperature difference (NETD) to assess probability of detecting (POD) anomalies.

  15. Temperature profiles of different cooling methods in porcine pancreas procurement.

    PubMed

    Weegman, Bradley P; Suszynski, Thomas M; Scott, William E; Ferrer Fábrega, Joana; Avgoustiniatos, Efstathios S; Anazawa, Takayuki; O'Brien, Timothy D; Rizzari, Michael D; Karatzas, Theodore; Jie, Tun; Sutherland, David E R; Hering, Bernhard J; Papas, Klearchos K

    2014-01-01

    Porcine islet xenotransplantation is a promising alternative to human islet allotransplantation. Porcine pancreas cooling needs to be optimized to reduce the warm ischemia time (WIT) following donation after cardiac death, which is associated with poorer islet isolation outcomes. This study examines the effect of four different cooling Methods on core porcine pancreas temperature (n = 24) and histopathology (n = 16). All Methods involved surface cooling with crushed ice and chilled irrigation. Method A, which is the standard for porcine pancreas procurement, used only surface cooling. Method B involved an intravascular flush with cold solution through the pancreas arterial system. Method C involved an intraductal infusion with cold solution through the major pancreatic duct, and Method D combined all three cooling Methods. Surface cooling alone (Method A) gradually decreased core pancreas temperature to <10 °C after 30 min. Using an intravascular flush (Method B) improved cooling during the entire duration of procurement, but incorporating an intraductal infusion (Method C) rapidly reduced core temperature 15-20 °C within the first 2 min of cooling. Combining all methods (Method D) was the most effective at rapidly reducing temperature and providing sustained cooling throughout the duration of procurement, although the recorded WIT was not different between Methods (P = 0.36). Histological scores were different between the cooling Methods (P = 0.02) and the worst with Method A. There were differences in histological scores between Methods A and C (P = 0.02) and Methods A and D (P = 0.02), but not between Methods C and D (P = 0.95), which may highlight the importance of early cooling using an intraductal infusion. In conclusion, surface cooling alone cannot rapidly cool large (porcine or human) pancreata. Additional cooling with an intravascular flush and intraductal infusion results in improved core porcine pancreas temperature profiles during procurement and

  16. LED Curing Lights and Temperature Changes in Different Tooth Sites

    PubMed Central

    Armellin, E.; Bovesecchi, G.; Coppa, P.; Pasquantonio, G.; Cerroni, L.

    2016-01-01

    Objectives. The aim of this in vitro study was to assess thermal changes on tooth tissues during light exposure using two different LED curing units. The hypothesis was that no temperature increase could be detected within the dental pulp during polymerization irrespective of the use of a composite resin or a light-curing unit. Methods. Caries-free human first molars were selected, pulp residues were removed after root resection, and four calibrated type-J thermocouples were positioned. Two LED lamps were tested; temperature measurements were made on intact teeth and on the same tooth during curing of composite restorations. The data was analyzed by one-way analysis of variance (ANOVA), Wilcoxon test, Kruskal-Wallis test, and Pearson's χ2. After ANOVA, the Bonferroni multiple comparison test was performed. Results. Polymerization data analysis showed that in the pulp chamber temperature increase was higher than that without resin. Starlight PRO, in the same condition of Valo lamp, showed a lower temperature increase in pre- and intrapolymerization. A control group (without composite resin) was evaluated. Significance. Temperature increase during resin curing is a function of the rate of polymerization, due to the exothermic polymerization reaction, the energy from the light unit, and time of exposure. PMID:27195282

  17. Studies of silicon quantum dots prepared at different substrate temperatures

    NASA Astrophysics Data System (ADS)

    Al-Agel, Faisal A.; Suleiman, Jamal; Khan, Shamshad A.

    2017-03-01

    In this research work, we have synthesized silicon quantum dots at different substrate temperatures 193, 153 and 123 K at a fixed working pressure 5 Torr. of Argon gas. The structural studies of these silicon quantum dots have been undertaken using X-ray diffraction, Field Emission Scanning Electron Microscopy (FESEM) and High Resolution Transmission Electron Microscopy (HRTEM). The optical and electrical properties have been studied using UV-visible spectroscopy, Fourier transform infrared (FTIR) spectroscopy, Fluorescence spectroscopy and I-V measurement system. X-ray diffraction pattern of Si quantum dots prepared at different temperatures show the amorphous nature except for the quantum dots synthesized at 193 K which shows polycrystalline nature. FESEM images of samples suggest that the size of quantum dots varies from 2 to 8 nm. On the basis of UV-visible spectroscopy measurements, a direct band gap has been observed for Si quantum dots. FTIR spectra suggest that as-grown Si quantum dots are partially oxidized which is due exposure of as-prepared samples to air after taking out from the chamber. PL spectra of the synthesized silicon quantum dots show an intense peak at 444 nm, which may be attributed to the formation of Si quantum dots. Temperature dependence of dc conductivity suggests that the dc conductivity enhances exponentially by raising the temperature. On the basis above properties i.e. direct band gap, high absorption coefficient and high conductivity, these silicon quantum dots will be useful for the fabrication of solar cells.

  18. Predicting thermal inactivation in media of different pH of Salmonella grown at different temperatures.

    PubMed

    Mañas, Pilar; Pagán, Rafael; Raso, Javier; Condón, Santiago

    2003-10-15

    The influence of the growth temperature and the pH of the heating medium on the heat resistance at different temperatures of Salmonella typhimurium ATCC 13311 was studied and described mathematically. The shift of the growth temperature from 10 to 37 degrees C increased heat resistance of S. typhimurium fourfold. The pH of the heating medium at which heat resistance was maximum was pH 6 for cells grown at 37 degrees C, but changed with growth temperature. The alkalinization of the heating medium from pH 6 to pH 7.7 decreased the heat resistance of cells grown at 37 degrees C by a factor of 3. Neither the growth temperature nor the pH modified the z values significantly (4.9 degrees C). The decimal reduction times at different treatment temperatures, in buffers of different pH of cells of S. typhimurium grown at different temperatures, were accurately described by a mathematical equation (correlation coefficient of 0.97). This equation was also tested for Salmonella senftenberg 775W (ATCC 43845) and Salmonella enteritidis ATCC 13076, strains in which the correlation coefficients between the observed and the theoretically calculated values were 0.91 and 0.98, respectively.

  19. [Temperature differences of air-rice plant under different irrigated water depths at spiking stage].

    PubMed

    Zhang, Bin; Zheng, Jian-chu; Huang, Shan; Tian, Yun-lu; Peng, Lan; Bian, Xin-min; Zhang, Wei-jian

    2008-01-01

    With rice cultivars Yangdao 6, Yangjing 9538 and Wuxiangjing 14 as test materials, field experiment was conducted to study the effects of 3 irrigated water depths (0 cm, 2-4 cm, and > 10 cm) on the temperature of different parts of rice plant at spiking stage. The results showed that from 10:30 to 15:00 on sunny days, irrigated water depth on paddy field had significant effects on the temperature of field surface, middle part of rice plant, and rice spike. The higher the water depth on field surface, the lower the temperature of rice plant and rice spike. At the water level > 10 cm, the average temperature differences between air and the rice spike, middle part of rice plant and field surface of these three cultivars were 1.37, 2.98 and 4.12 degrees C higher than those at the water depth of 0 cm, and 0.67, 1.59 and 2.17 degrees C higher than those at the water depth of 2-4 cm, respectively. In addition, the temperature differences were 0.71, 1.39 and 1.95 degrees C higher at the water depth of 2-4 cm than those at the water depth of 0 cm, respectively. Obvious temperature differences of air-rice plant were also observed among the three rice varieties under different irrigated water depths. The analysis of the characteristics of temperature transfer among field surface, middle part of plant and rice spike indicated that the temperature transfer patterns under all test water management regimes accorded with the principles of energy transfer, suggesting that keeping proper water depth on the field surface at rice spiking stage contributed great to the decrease of rice spike temperature and the alleviation of rice heat injury.

  20. Refinement of thermal imager minimum resolvable temperature difference calculating method

    NASA Astrophysics Data System (ADS)

    Kolobrodov, V. G.; Mykytenko, V. I.

    2015-11-01

    Calculating methods, which accurately predict minimum resolvable temperature difference (MRTD), are of significant interest for many years. The article deals with improvement the accuracy of determining the thermal imaging system MRTD by elaboration the visual perception model. We suggest MRTD calculating algorithm, which is based on a reliable approximation of the human visual system modulation transfer function (MTF) proposed by N. Nill. There was obtained a new expression for the bandwidth evaluation, which is independent of angular size of the Foucault bar target.

  1. Performance of NiTi endodontic instrument under different temperatures.

    PubMed

    Jamleh, Ahmed; Yahata, Yoshio; Ebihara, Arata; Atmeh, Amre R; Bakhsh, Turki; Suda, Hideaki

    2016-09-01

    The purpose of this study was to test nickel titanium (NiTi) instrument performance under different surrounding temperatures. Twenty-four superelastic NiTi instruments with a conical shape comprising a 0.30-mm-diameter tip and 0.06 taper were equally divided into 3 groups according to the temperature employed. Using a specially designed cyclic fatigue testing apparatus, each instrument was deflected to give a curvature 10 mm in radius and a 30° angle. This position was kept as the instrument was immersed in a continuous flow of water under a temperature of 10, 37, or 50 °C for 20 s to calculate the deflecting load (DL). In the same position, the instrument was then allowed to rotate at 300 rpm to fracture, and the working time was converted to the number of cycles to fracture (NCF). The statistical significance was set at p = 0.05. The mean DL (in N) and NCF (in cycles) of the groups at 10, 37, and 50 °C were 10.16 ± 1.36 and 135.50 ± 31.48, 13.50 ± 0.92 and 89.20 ± 16.44, and 14.70 ± 1.21 and 65.50 ± 15.90, respectively. The group at 10 °C had significantly the lowest DL that favorably resulted in the highest NCF. Within the limitations of this study, the surrounding temperature influences the cyclic fatigue resistance and DL of the superelastic NiTi instruments. Lower temperatures are found to favorably decrease the DL and extend the lifetime of the superelastic NiTi instrument. Further NiTi instrument failure studies should be performed under simulated body temperature.

  2. Piglets’ Surface Temperature Change at Different Weights at Birth

    PubMed Central

    Caldara, Fabiana Ribeiro; dos Santos, Luan Sousa; Machado, Sivanilza Teixeira; Moi, Marta; de Alencar Nääs, Irenilza; Foppa, Luciana; Garcia, Rodrigo Garófallo; de Kássia Silva dos Santos, Rita

    2014-01-01

    The study was carried out in order to verify the effects of piglets’ weight at birth on their surface temperature change (ST) after birth, and its relationship with ingestion time of colostrum. Piglets from four different sows were weighed at birth and divided into a totally randomized design with three treatments according to birth weight (PBW): T1 - less than 1.00 kg, T2 - 1.00 to 1.39 kg, and T3 - higher than or equal to 1.40 kg. The time spent for the first colostrum ingestion was recorded (TFS). Images of piglets’ surface by thermal imaging camera were recorded at birth (STB) and 15, 30, 45, 60, and 120 min after birth. The air temperature and relative humidity were recorded every 30 min and the indexes of temperature and humidity (THI) were calculated. A ST drop after 15 min from birth was observed, increasing again after sixty minutes. Positive correlations were found between the PBW and the ST at 30 and 45 min after birth. The PBW was negatively correlated with the TFS. The THI showed high negative correlations (−0.824 and −0.815) with STB and after 15 min from birth. The piglet’s surface temperature at birth was positively correlated with temperature thereof to 15 min, influencing therefore the temperatures in the interval of 45 to 120 min. The birth weight contributes significantly to postnatal hypothermia and consequently to the time it takes for piglets ingest colostrum, requiring special attention to those of low birth weight. PMID:25049971

  3. Piglets' surface temperature change at different weights at birth.

    PubMed

    Caldara, Fabiana Ribeiro; Dos Santos, Luan Sousa; Machado, Sivanilza Teixeira; Moi, Marta; de Alencar Nääs, Irenilza; Foppa, Luciana; Garcia, Rodrigo Garófallo; de Kássia Silva Dos Santos, Rita

    2014-03-01

    The study was carried out in order to verify the effects of piglets' weight at birth on their surface temperature change (ST) after birth, and its relationship with ingestion time of colostrum. Piglets from four different sows were weighed at birth and divided into a totally randomized design with three treatments according to birth weight (PBW): T1 - less than 1.00 kg, T2 - 1.00 to 1.39 kg, and T3 - higher than or equal to 1.40 kg. The time spent for the first colostrum ingestion was recorded (TFS). Images of piglets' surface by thermal imaging camera were recorded at birth (STB) and 15, 30, 45, 60, and 120 min after birth. The air temperature and relative humidity were recorded every 30 min and the indexes of temperature and humidity (THI) were calculated. A ST drop after 15 min from birth was observed, increasing again after sixty minutes. Positive correlations were found between the PBW and the ST at 30 and 45 min after birth. The PBW was negatively correlated with the TFS. The THI showed high negative correlations (-0.824 and -0.815) with STB and after 15 min from birth. The piglet's surface temperature at birth was positively correlated with temperature thereof to 15 min, influencing therefore the temperatures in the interval of 45 to 120 min. The birth weight contributes significantly to postnatal hypothermia and consequently to the time it takes for piglets ingest colostrum, requiring special attention to those of low birth weight.

  4. Effect of different alkaline solutions on crystalline structure of cellulose at different temperatures.

    PubMed

    Keshk, Sherif M A S

    2015-01-22

    Effect of alkaline solutions such as 10% NaOH, NaOH/urea and NaOH/ethylene glycol solutions on crystalline structure of different cellulosic fibers (cotton linter and filter paper) was investigated at room temperature and -4°C. The highest dissolution of cotton linter and filter paper was observed in NaOH/ethylene glycol at both temperatures. X-ray patterns of treated cotton linter with different alkaline solutions at low temperature showed only two diffractions at 2θ=12.5° and 21.0°, which belonged to the crystalline structure of cellulose II. CP/MAS (13)C NMR spectra showed the doublet peaks at 89.2 ppm and 88.3 ppm representing C4 resonance for cellulose I at room temperature, Whereas, at low temperature the doublet peaks were observed at 89.2 ppm and 87.8 ppm representing C4 resonance for cellulose II. Degree of polymerization of cellulose plays an important role in cellulose dissolution in different alkaline solutions and temperatures, where, a low temperature gives high dissolutions percentage with change in crystalline structure from cellulose I to cellulose II forms.

  5. The Effects of High Temperature on Gessoes with Different Admixtures

    NASA Astrophysics Data System (ADS)

    Budu, Ana-Maria; Sandu, Ion; Cristache, Raluca Anamaria

    2014-11-01

    This paper presents the effects of temperature on gessoes that have different substances added, usually used in painting or restoration to enhance the flexibility of the ground layer or to create a suitable gesso for the specific painting technique. Five samples of gesso were made and applied on Balsa wood (a dry, stable wood that is used in restoration for completing the missing elements of the panel). After the thermal treatment, the samples were analyzed optical, by microscopy and colorimetry. The results showed small differences in colour, but no cracks of the gessoes

  6. Stall cleanliness and stall temperature of two different freestall bases.

    PubMed

    Wadsworth, B A; Stone, A E; Clark, J D; Ray, D L; Bewley, J M

    2015-06-01

    The objective of this study was to describe the differences in freestall cleanliness and stall temperature between a barn with Dual Chamber Cow Waterbeds (DCCW; Advanced Comfort Technology, Reedsburg, WI) and a barn with rubber-filled mattresses at the University of Kentucky Coldstream Dairy Research Farm from January 18, 2012, to May 3, 2013. Stall cleanliness was measured twice weekly (n=134) by the same 2 observers using a 0.91 m×0.91 m wire grid containing 128 equally sized rectangles (10.16 cm×5.08 cm). This grid was centered at the rear portion of the stall; a rectangle that was visibly wet or had any amount of feces present was defined as a dirty rectangle. Weekly stall temperature (n=66) was measured by the same observer during a.m. milkings in the same predetermined stalls. Feces and wet sawdust were removed from the stalls before stall temperatures were acquired. Temperatures were obtained using a handheld thermometer at 30.48 cm above the stall base as determined via dual laser measurements. Stall temperature was measured on the front, middle, and back of the stall first with clean sawdust and then with the sawdust removed from the stall and wiped clean with a towel. Daily temperature-humidity index (THI) was calculated using Kentucky climate data calculated through the University of Kentucky College of Agriculture via a data logger, located 5.63 km from the Coldstream Dairy Farm. Stall cleanliness was not different between the DCCW barn (26.09±0.89 rectangles) and the rubber-filled mattress barn (23.70±0.89 rectangles). Mean THI throughout the study was 64.39±0.82. Stall temperature was different among THI categories. Temperature-humidity index categories 1 (coldest), 2, 3, and 4 (warmest) had THI ranges of 22.94 to 50.77, 50.77 to 64.88, 64.88 to 78.75, and 78.75 to 101.59, respectively. Stall temperatures (°C; least squares means±SE) were 2.26±0.30, 8.86±0.30, 15.52±0.30, and 20.95±0.30 for THI categories 1 to 4, respectively. Stalls with

  7. Flowability analysis of uranium dioxide powder at different temperatures containing different lubricants.

    PubMed

    Santana, H H S; Maier, G; Ródenas, J

    2011-08-01

    Powder flowability characteristics are often intentionally modified in order to improve their production process. The UO(2) pellet manufacturing process can consist of many steps, e.g. milling, granulation, homogenization, die filling for pressing, etc. By the addition of flow additives, lubricants or glidants the desired workability can be achieved. Temperature also influences the powder processability, leading to an easier or more complex powder flow. The work aims to determine some flowability characteristics for UO(2) powder at different temperatures.

  8. Chlorella Virus Encoded Deoxyuridine triphosphatases Exhibit different Temperature Optima

    SciTech Connect

    Zhang,Y.; Moriyama, H.; Homma, K.; Van Etten, J.

    2005-01-01

    A putative deoxyuridine triphosphatase (dUTPase) gene from chlorella virus PBCV-1 was cloned, and the recombinant protein was expressed in Escherichia coli. The recombinant protein has dUTPase activity and requires Mg{sup 2+} for optimal activity, while it retains some activity in the presence of other divalent cations. Kinetic studies of the enzyme revealed a K{sub m} of 11.7 {mu}M, a turnover k{sub cat} of 6.8 s{sup -1}, and a catalytic efficiency of k{sub cat}/K{sub m} = 5.8 x 105 M{sup -1} s{sup -1}. dUTPase genes were cloned and expressed from two other chlorella viruses IL-3A and SH-6A. The two dUTPases have similar properties to PBCV-1 dUTPase except that IL-3A dUTPase has a lower temperature optimum (37{sup o}C) than PBCV-1 dUTPase (50{sup o}C). The IL-3A dUTPase differs from the PBCV-1 enzyme by nine amino acids, including two amino acid substitutions, Glu81{yields}Ser81 and Thr84{yields}Arg84, in the highly conserved motif III of the proteins. To investigate the difference in temperature optima between the two enzymes, homology modeling and docking simulations were conducted. The results of the simulation and comparisons of amino acid sequence suggest that adjacent amino acids are important in the temperature optima. To confirm this suggestion, three site-directed amino acid substitutions were made in the IL-3A enzyme: Thr84{yields}Arg84, Glu81{yields}Ser81, and Glu81{yields}Ser81 plus Thr84{yields}Arg84. The single substitutions affected the optimal temperature for enzyme activity. The temperature optimum increased from 37 to 55{sup o}C for the enzyme containing the two amino acid substitutions. We postulate that the change in temperature optimum is due to reduction in charge and balkiness in the active cavity that allows more movement of the ligand and protein before the enzyme and substrate complex is formed.

  9. Interhemispheric temperature difference as a predictor of boreal winter ENSO

    NASA Astrophysics Data System (ADS)

    Piskozub, Jacek; Gutowska, Dorota

    2013-04-01

    We use statistical analysis to show statistically significant relationship between the boreal winter MEI index of ENSO and HadCRUT3 temperature difference between Northern and Southern hemispheres (NH - SH) during the preceding summer. Correlation values increase (in absolute terms) if the correlated time periods are increased from month to seasonal length. For example December and January (DJ) MEI values anticorrelate stronger with the preceding MJJA period than with any of the four months taken separately. We believe this is further evidence that the correlation is caused by a real physical process as increase of the averaging period tends to reduce statistical noise. The motivation for looking for such a relationship comes from review of literature on paleoclimatic ENSO behavior. We have noticed that in many cases relatively cold NH coincided with "strong ENSO" (frequent El Niños), for example the Ice Age periods and Little Ice Age. On the other hand periods of relatively warm NH (the Holocene climate optimum or Medieval Climate Anomaly) are coincident with frequent or even "permanent" La Niñas. This relationship suggest the influence of the position of Intertropical Convergence Zone (ITCZ) on the frequency of El Niños. The simplest physical mechanism of the relationship is that the positive (negative) NH-SH temperature difference causes a north (south) shift of ITCZ with a parallel shift of trade wind zones. The North-South orographic difference between the Panama Isthmus and the South America may cause stronger (weaker) trade winds in Eastern Tropical Pacific increasing (decreasing) the thermochemical tilt which, in turn, causes a more negative (positive) ENSO values. Of course this may be only a first approximation of the real mechanism of this "teleconnection". The correlations we have found are not strong even if statistically significant. For example, the MJJA NH-SH temperature vs. DJ MEI correlation has r = -0.28 implying it explains only 8% of boreal

  10. Mechanism of boron uptake by hydrocalumite calcined at different temperatures.

    PubMed

    Qiu, Xinhong; Sasaki, Keiko; Takaki, Yu; Hirajima, Tsuyoshi; Ideta, Keiko; Miyawaki, Jin

    2015-04-28

    Hydrocalumite (Ca-Al-layered double hydroxide (LDH)) was prepared and applied for the removal of borate. The properties of Ca-Al-LDH calcined at different temperatures were diverse, which affected the sorption density and mechanism of boron species. The sorption density increased with increase in calcined temperature and the sample calcined at 900°C (Ca-Al-LDH-900) showed the maximum sorption density in this work. The solid residues after sorption were characterized by (11)B NMR, (27)Al NMR, SEM, and XRD to investigate the sorption mechanism. Dissolution-reprecipitation was the main mechanism for sorption of borate in Ca-Al-LDH. For Ca-Al-LDH calcined at 300 and 500°C, regeneration occurred in a short time and the newly forming LDHs were decomposed to release Ca(2+) ions and formed ettringite with borate. Two stages occurred in the sorption of boron by Ca-Al-LDH calcined at 900°C. In the first stage, boron species adsorbed on the alumina gel resulting from the hydration of calcined products. In this stage, borate was included as an interlayer anion into the newly forming LDHs in the following stage, and then immobilized as HBO3(2-) into the interlayer, most the LDHs.

  11. Dielectric Behavior of Biomaterials at Different Frequencies on Room Temperature

    NASA Astrophysics Data System (ADS)

    Shrivastava, B. D.; Barde, Ravindra; Mishra, A.; Phadke, S.

    2014-09-01

    Propagation of electromagnetic (EM) waves in radiofrequency (RF) and microwave systems is described mathematically by Maxwell's equations with corresponding boundary conditions. Dielectric properties of lossless and lossy materials influence EM field distribution. For a better understanding of the physical processes associated with various RF and microwave devices, it is necessary to know the dielectric properties of media that interact with EM waves. For telecommunication and radar devices, variations of complex dielectric permittivity (referring to the dielectric property) over a wide frequency range are important. For RF and microwave applicators intended for thermal treatments of different materials at ISM (industrial, scientific, medical) frequencies, one needs to study temperature and moisture content dependencies of the Permittivity of the treated materials. Many techniques have been developed for the measurement of materials. In the present paper authors used Bones and scales of Fish taken from Narmada River (Rajghat Dist. Barwani) as biomaterials. Dielectric properties of Biomaterials with the frequency range from 1Hz to 10 MHz at room temperature with low water content were measured by in-situ performance dielectric kit. Analysis has been done by Alpha high performance impedance analyzer and LCR meters. The experimental work were carried out in Inter University Consortium UGC-DAE, CSR center Indore MP. Measured value indicates the dielectric constant (ɛ') dielectric loss (ɛ") decreases with increasing frequency while conductivity (σ) increases with frequency increased.

  12. Maximum vehicle cabin temperatures under different meteorological conditions

    NASA Astrophysics Data System (ADS)

    Grundstein, Andrew; Meentemeyer, Vernon; Dowd, John

    2009-05-01

    A variety of studies have documented the dangerously high temperatures that may occur within the passenger compartment (cabin) of cars under clear sky conditions, even at relatively low ambient air temperatures. Our study, however, is the first to examine cabin temperatures under variable weather conditions. It uses a unique maximum vehicle cabin temperature dataset in conjunction with directly comparable ambient air temperature, solar radiation, and cloud cover data collected from April through August 2007 in Athens, GA. Maximum cabin temperatures, ranging from 41-76°C, varied considerably depending on the weather conditions and the time of year. Clear days had the highest cabin temperatures, with average values of 68°C in the summer and 61°C in the spring. Cloudy days in both the spring and summer were on average approximately 10°C cooler. Our findings indicate that even on cloudy days with lower ambient air temperatures, vehicle cabin temperatures may reach deadly levels. Additionally, two predictive models of maximum daily vehicle cabin temperatures were developed using commonly available meteorological data. One model uses maximum ambient air temperature and average daily solar radiation while the other uses cloud cover percentage as a surrogate for solar radiation. From these models, two maximum vehicle cabin temperature indices were developed to assess the level of danger. The models and indices may be useful for forecasting hazardous conditions, promoting public awareness, and to estimate past cabin temperatures for use in forensic analyses.

  13. Maximum vehicle cabin temperatures under different meteorological conditions.

    PubMed

    Grundstein, Andrew; Meentemeyer, Vernon; Dowd, John

    2009-05-01

    A variety of studies have documented the dangerously high temperatures that may occur within the passenger compartment (cabin) of cars under clear sky conditions, even at relatively low ambient air temperatures. Our study, however, is the first to examine cabin temperatures under variable weather conditions. It uses a unique maximum vehicle cabin temperature dataset in conjunction with directly comparable ambient air temperature, solar radiation, and cloud cover data collected from April through August 2007 in Athens, GA. Maximum cabin temperatures, ranging from 41-76 degrees C, varied considerably depending on the weather conditions and the time of year. Clear days had the highest cabin temperatures, with average values of 68 degrees C in the summer and 61 degrees C in the spring. Cloudy days in both the spring and summer were on average approximately 10 degrees C cooler. Our findings indicate that even on cloudy days with lower ambient air temperatures, vehicle cabin temperatures may reach deadly levels. Additionally, two predictive models of maximum daily vehicle cabin temperatures were developed using commonly available meteorological data. One model uses maximum ambient air temperature and average daily solar radiation while the other uses cloud cover percentage as a surrogate for solar radiation. From these models, two maximum vehicle cabin temperature indices were developed to assess the level of danger. The models and indices may be useful for forecasting hazardous conditions, promoting public awareness, and to estimate past cabin temperatures for use in forensic analyses.

  14. Considerations for modeling thin cirrus effects via brightness temperature differences

    NASA Technical Reports Server (NTRS)

    Schmidt, E. O.; Arduini, R. F.; Wielicki, B. A.; Stone, R. S.; Tsay, S.-C.

    1995-01-01

    Brightness temperature difference (BTD) values are calculated for selected Geostationary Operational Environmental Satellite (GOES-6) channels (3.9, 12.7 micrometer) and Advanced Very High Resolution Radiometer channels (3.7, 12.0 micrometer). Daytime and nighttime discrimination of particle size information is possible given the infrared cloud extinction optical depth and the BTD value. BTD values are presented and compared for cirrus clouds composed of equivalent ice spheres (volume, surface area) versus randomly oriented hexagonal ice crystals. The effect of the hexagonal ice crystals is to increase the magnitude of the BTD values calculated relative to equivalent ice sphere (volume, surface area) BTDs. Equivalent spheres (volume or surface area) do not do a very good job of modeling hexagonal ice crystal effects on BTDs; however, the use of composite spheres improves the simulation and offers interesting prospects. Careful consideration of the number of Legendre polynomial coefficients used to fit the scattering phase functions is crucial to realistic modeling of cirrus BTDs. Surface and view-angle effects are incorporated to provide more realistic simulation.

  15. Study on different characteristics of doped tri calcium phosphate at different sintering temperatures

    NASA Astrophysics Data System (ADS)

    Samanta, Sujan Krishna; Chanda, Abhijit

    2016-04-01

    Pure β-tricalcium phosphate (β-TCP), Zn-doped (3wt %) β-TCP and Mg- doped (3wt %) β-TCP samples were prepared by using a wet chemical precipitation synthesis technique, followed by calcination at 800 °C in air. The developed materials were subjected to sintering at different temperatures. Density and porosity were compared. The X-ray diffractometry (XRD) and Fourier-transformed infrared (FTIR) spectrometer were used to examine the changes in crystalline phases and presence of functional groups of TCP ceramics. The scanning electron microscopy (SEM) was used to study the pore formation, pore size, grain size.

  16. N₂O accumulation from denitrification under different temperatures.

    PubMed

    Poh, Leong Soon; Jiang, Xie; Zhang, Zhongbo; Liu, Yu; Ng, Wun Jern; Zhou, Yan

    2015-11-01

    The effects of temperature on nitrous oxide (N2O) accumulation during denitrification and denitritation were investigated. Batch experiments were performed to measure N2O accumulation at 25 and 35 °C. More N2O accumulation was observed during denitritation at the higher temperature as compared with full denitrification and low temperature tests. The highest nitrite concentration tested in this study (25 mg/L NO2 (-)N and pH 8.0) did not show inhibitory effect on N2O reduction. It was found that the major cause of more N2O accumulation during denitrification at higher temperature was due to higher N2O production rate and lower N2O solubility. Specific nitrate, nitrite, and N2O reduction rates increased 62, 61, and 41 %, respectively, when temperature rose from 25 to 35 °C. The decrease of N2O solubility in mixed liquor at 35 °C (when compared to 25 °C) resulted in faster diffusing rate of N2O from liquid to gas phase. It was also more difficult for gas phase N2O to be re-dissolved. The diffused N2O was then accumulated in the headspace, which was not available for denitrification by denitrifiers. The results of this study suggest higher temperature may worsen N2O emission from wastewater treatment plants (WWTPs).

  17. Intraspecific variation in temperature dependence of gas exchange characteristics among Plantago asiatica ecotypes from different temperature regimes.

    PubMed

    Ishikawa, Kazumasa; Onoda, Yusuke; Hikosaka, Kouki

    2007-01-01

    There are large inter- and intraspecific differences in the temperature dependence of photosynthesis, but the physiological cause of the variation is poorly understood. Here, the temperature dependence of photosynthesis was examined in three ecotypes of Plantago asiatica transplanted from different latitudes, where the mean annual temperature varies between 7.5 and 16.8 degrees C. Plants were raised at 15 or 30 degrees C, and the CO(2) response of photosynthetic rates was determined at various temperatures. When plants were grown at 30 degrees C, no difference was found in the temperature dependence of photosynthesis among ecotypes. When plants were grown at 15 degrees C, ecotypes from a higher latitude maintained a relatively higher photosynthetic rate at low measurement temperatures. This difference was caused by a difference in the balance between the capacities of two processes, ribulose-1,5-bisphosphate regeneration (J(max)) and carboxylation (V(cmax)), which altered the limiting step of photosynthesis at low temperatures. The organization of photosynthetic proteins also varied among ecotypes. The ecotype from the highest latitude increased the J(max) : V(cmax) ratio with decreasing growth temperature, while that from the lowest latitude did not. It is concluded that nitrogen partitioning in the photosynthetic apparatus and its response to growth temperature were different among ecotypes, which caused an intraspecific variation in temperature dependence of photosynthesis.

  18. Comparison of different measuring methods for body temperature in lactating cows under different climatic conditions.

    PubMed

    Ammer, Stefanie; Lambertz, Christian; Gauly, Matthias

    2016-05-01

    The aim of the research described here was to compare different methods of body temperature (BT) measurements in dairy cows. It was hypothesised that reticular temperature (RET) values reflect the physiological status of the animals in an equivalent way to rectal (RT) and vaginal (VT) measurements. RT, VT and RET temperatures of twelve lactating Holstein-Friesian cows were measured over five consecutive days in June and October 2013. While RT and VT were manually measured three times a day, RET was automatically recorded at 10 min intervals using a bolus in the reticulum. For comparison with RT and VT, different RET values were used: single values at the respective recording times (RET-SIN), and mean (RET-MEAN) and median (RET-MED) values of 2 h prior to RT and VT measurements. Overall, body temperatures averaged 38·1 ± 0·6, 38·2 ± 0·4, 38·7 ± 0·9, 38·5 ± 0·7 and 38·7 ± 0·5 °C for RT, VT, RET-SIN, RET-MEAN and RET-MED, respectively. RT and VT were lower than all RET measurements, while RET-SIN and RET-MED were higher than RET-MEAN (P < 0·001). RET-MEAN and RET-MED values were higher in the morning, whereas RT and VT were greatest in the evening (P < 0·001). Overall, records of RT and VT were strongly correlated (r = 0·75; P < 0·001). In contrast to RET-SIN and RET-MEAN, RET-MED was higher correlated to RT and VT. In June, coefficients were higher between all methods than in October. Relation of barn T to RT and VT was stronger when compared to RET measurements. RET-SIN was higher correlated to barn T than RET-MEAN or RET-MED. Correlation between VT and barn T was strongest (r = 0·48; P < 0·001). In summary, RET-MED showed highest correlation with VT and RT. However, single RET measurements (influenced by water or feed intake) can lead to extreme variations and differences to single VT and RT values.

  19. [Fluoride emission from different soil minerals at high temperatures].

    PubMed

    Wu, W; Xie, Z; Xu, J; Liu, C

    2001-03-01

    The emission characteristics of fluoride pollutants from montmorillonite, kaolinite, vermiculite, geothite and allophane were studied to elucidate the mechanism of fluoride-releasing from soils during brick and tile making at high temperatures from 300 degrees C to 1000 degrees C. The rate of fluoride emission varied with temperature, mineral type, heating time, specific surface area and cations added to minerals. The escape of crystalline water resulting from crystal lattice collapse at a certain high temperature was found to affect the rate of fluoride emission. Calcium compounds could decrease fluoride emission rate from montmorillonite. At 800 degrees C, the rate of fluoride emission from Ca-treated montmorillonite decreased by 59.6% compared to untreated montmorillonite. The order for fluoride-fixing capacity of the 5 calcium compounds at 800 degrees C was as follows: CaCO3 > CaO > Ca3(PO4)2 > Ca(OH)2 > CaSO4.

  20. Equilibrium free-energy differences at different temperatures from a single set of nonequilibrium transitions

    NASA Astrophysics Data System (ADS)

    Patra, Puneet Kumar; Bhattacharya, Baidurya

    2016-10-01

    Crook's fluctuation theorem (CFT) and Jarzynski equality (JE) are effective tools for obtaining free-energy difference Δ F (λA→λB,T0) through a set of finite-time protocol driven nonequilibrium transitions between two equilibrium states A and B [parametrized by the time-varying protocol λ (t ) ] at the same temperature T0. Using the generalized dimensionless work function Δ WG , we extend CFT to transitions between two nonequilibrium steady states (NESSs) created by a thermal gradient. We show that it is possible, provided the period over which the transitions occur is sufficiently long, to obtain Δ F (λA→λB,T0) for different values of T0, using the same set of finite-time transitions between these two NESSs. Our approach thus completely eliminates the need to make new samples for each new T0. The generalized form of JE arises naturally as the average of the exponentiated Δ WG . The results are demonstrated on two test cases: (i) a single particle quartic oscillator having a known closed form Δ F , and (ii) a one-dimensional ϕ4 chain. Each system is sampled from the canonical distribution at an arbitrary T' with λ =λA , then subjected to a temperature gradient between its ends, and after steady state is reached, the protocol change λA→λB is effected in time τ , following which Δ WG is computed. The reverse path likewise initiates in equilibrium at T' with λ =λB and the protocol is time reversed leading to λ =λA and the reverse Δ WG . Our method is found to be more efficient than either JE or CFT when free-energy differences at multiple T0's are required for the same system.

  1. Longevity of crapemyrtle pollen stored at different temperatures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Temperatures for storage of crapemyrtle (Lagerstroemia app.) pollen over time were studied using clones of two interspecific hybrids (L. 'Cheyenne' and L. 'Wichita') and five species (L. indica 'Catawba', L. subcostata (NA 40181), L. limii, L. speciosa, and L. fauriei 'Kiowa'). Pollen samples were s...

  2. Human local and total heat losses in different temperature.

    PubMed

    Wang, Lijuan; Yin, Hui; Di, Yuhui; Liu, Yanfeng; Liu, Jiaping

    2016-04-01

    This study investigates the effects of operative temperature on the local and total heat losses, and the relationship between the heat loss and thermal sensation. 10 local parts of head, neck, chest, abdomen, upper arm, forearm, hand, thigh, leg and foot are selected. In all these parts, convection, radiation, evaporation, respiration, conduction and diffusion heat losses are analyzed when operative temperature is 23, 28, 33 and 37 °C. The local heat losses show that the radiation and convection heat losses are mainly affected by the area of local body, and the heat loss of the thigh is the most in the ten parts. The evaporation heat loss is mainly affected by the distribution of sweat gland, and the heat loss of the chest is the most. The total heat loss of the local body shows that in low temperature, the thigh, leg and chest have much heat loss, while in high temperature, the chest, abdomen, thigh and head have great heat loss, which are useful for clothing design. The heat losses of the whole body show that as the operative temperature increases, the radiation and convection heat losses decrease, the heat losses of conduction, respiration, and diffusion are almost constant, and the evaporation heat loss increases. By comparison, the heat loss ratios of the radiation, convection and sweat evaporation, are in agreement with the previous researches. At last, the formula about the heat loss ratio of convection and radiation is derived. It's useful for thermal comfort evaluation and HVAC (heating, ventilation and air conditioning) design.

  3. Differences between true mean temperatures and means calculated with four different approaches: a case study from three Croatian stations

    NASA Astrophysics Data System (ADS)

    Bonacci, Ognjen; Željković, Ivana

    2016-12-01

    Different countries use varied methods for daily mean temperature calculation. None of them assesses precisely the true daily mean temperature, which is defined as the integral of continuous temperature measurements in a day. Of special scientific as well as practical importance is to find out how temperatures calculated by different methods and approaches deviate from the true daily mean temperature. Five mean daily temperatures were calculated (T0, T1, T2, T3, T4) using five different equations. The mean of 24-h temperature observations during the calendar day is accepted to represent the true, daily mean T0. The differences Δi between T0 and four other mean daily temperatures T1, T2, T3, and T4 were calculated and analysed. In the paper, analyses were done with hourly data measured in a period from 1 January 1999 to 31 December 2014 (149,016 h, 192 months and 16 years) at three Croatian meteorological stations. The stations are situated in distinct climatological areas: Zagreb Grič in a mild climate, Zavižan in the cold mountain region and Dubrovnik in the hot Mediterranean. Influence of fog on the temperature is analysed. Special attention is given to analyses of extreme (maximum and minimum) daily differences occurred at three analysed stations. Selection of the fixed local hours, which is in use for calculation of mean daily temperature, plays a crucial role in diminishing of bias from the true daily temperature.

  4. Rate dependent of strength in metallic glasses at different temperatures

    PubMed Central

    Wang, Y. W.; Bian, X. L.; Wu, S. W.; Hussain, I.; Jia, Y. D.; Yi, J.; Wang, G.

    2016-01-01

    The correlation between the strength at the macroscale and the elastic deformation as well as shear cracking behavior at the microscale of bulk metallic glasses (BMGs) is investigated. The temperatures of 298 K and 77 K as well as the strain rate ranging from 10−6 s−1 to 10−2 s−1 are applied to the BMGs, in which the mechanical responses of the BMGs are profiled through the compression tests. The yield strength is associated with the activation of the elementary deformation unit, which is insensitive to the strain rate. The maximum compressive strength is linked to the crack propagation during shear fracture process, which is influenced by the strain rate. The cryogenic temperature of 77 K significantly improves the yield strength and the maximum compressive strength of the BMGs. PMID:27270688

  5. Liquid Temperature Measurements Using Two Different Tunable Hollow Prisms

    PubMed Central

    Calixto, Sergio; Rosete-Aguilar, Martha; Torres-Gomez, Ismael

    2017-01-01

    This paper describes the design, fabrication, and testing of two hollow prisms. One is a prism with a grating glued to its hypotenuse. This ensemble, prism + grating, is called a grism. It can be applied as an on-axis tunable spectrometer. The other hollow prism is a constant deviation one called a Pellin-Broca. It can be used as a tunable dispersive element in a spectrometer with no moving parts. The application of prisms as temperature sensors is shown. PMID:28146068

  6. Liquid Temperature Measurements Using Two Different Tunable Hollow Prisms.

    PubMed

    Calixto, Sergio; Rosete-Aguilar, Martha; Torres-Gomez, Ismael

    2017-01-29

    This paper describes the design, fabrication, and testing of two hollow prisms. One is a prism with a grating glued to its hypotenuse. This ensemble, prism + grating, is called a grism. It can be applied as an on-axis tunable spectrometer. The other hollow prism is a constant deviation one called a Pellin-Broca. It can be used as a tunable dispersive element in a spectrometer with no moving parts. The application of prisms as temperature sensors is shown.

  7. Benchmark analysis of forecasted seasonal temperature over different climatic areas

    NASA Astrophysics Data System (ADS)

    Giunta, G.; Salerno, R.; Ceppi, A.; Ercolani, G.; Mancini, M.

    2015-12-01

    From a long-term perspective, an improvement of seasonal forecasting, which is often exclusively based on climatology, could provide a new capability for the management of energy resources in a time scale of just a few months. This paper regards a benchmark analysis in relation to long-term temperature forecasts over Italy in the year 2010, comparing the eni-kassandra meteo forecast (e-kmf®) model, the Climate Forecast System-National Centers for Environmental Prediction (CFS-NCEP) model, and the climatological reference (based on 25-year data) with observations. Statistical indexes are used to understand the reliability of the prediction of 2-m monthly air temperatures with a perspective of 12 weeks ahead. The results show how the best performance is achieved by the e-kmf® system which improves the reliability for long-term forecasts compared to climatology and the CFS-NCEP model. By using the reliable high-performance forecast system, it is possible to optimize the natural gas portfolio and management operations, thereby obtaining a competitive advantage in the European energy market.

  8. Direct Emissivity Measurements of Painted Metals for Improved Temperature Estimation During Laser Damage Testing

    DTIC Science & Technology

    2014-03-27

    DIRECT EMISSIVITY MEASUREMENTS OF PAINTED METALS FOR IMPROVED TEMPERATURE ESTIMATION DURING LASER DAMAGE TESTING THESIS Sean M. Baumann, Civilian...radiance measurement, and fitted spectral radiance results, of one pixel on the back surface of a painted metal sample, far from laser burn-through hole...parabolic mirror NET noise-equivalent temperature xv DIRECT EMISSIVITY MEASUREMENTS OF PAINTED METALS FOR IMPROVED TEMPERATURE ESTIMATION DURING LASER DAMAGE

  9. Luminescence characteristics of nanoporous anodic alumina annealed at different temperatures

    NASA Astrophysics Data System (ADS)

    Ilin, D. O.; Vokhmintsev, A. S.; Weinstein, I. A.

    2016-09-01

    Anodic aluminum oxide (AAO) membranes with 100 µm thickness were synthesized in oxalic acid solution under constant current density. Grown samples were annealed in 500-1250 °C range for 5 h in air. Average pore diameter was evaluated using quantitative analysis of SEM images and appeared to be within 78-86 nm diapason. It was found there was a broad emission band in the 350-620 nm region of photoluminescence (PL) spectra in amorphous membranes which is attributed to F-type oxygen deficient centers or oxalic ions. It was shown that intensive red emission caused by Cr3+ (696 nm) and Mn4+ (680 nm) impurities dominates in PL of AAO samples with crystalline α- and δ-phases after annealing at 1100-1250 °C temperatures.

  10. Temperature-induced plasticity in membrane and storage lipid composition: thermal reaction norms across five different temperatures.

    PubMed

    Van Dooremalen, Coby; Koekkoek, Jacco; Ellers, Jacintha

    2011-02-01

    Temperature is a key environmental factor inducing phenotypic plasticity in a wide range of behavioral, morphological, and life history traits in ectotherms. The strength of temperature-induced responses in fitness-related traits may be determined by plasticity of the underlying physiological or biochemical traits. Lipid composition may be an important trait underlying fitness response to temperature, because it affects membrane fluidity as well as availability of stored energy reserves. Here, we investigate the effect of temperature on lipid composition of the springtail Orchesella cincta by measuring thermal reaction norms across five different temperatures after four weeks of cold or warm acclimation. Fatty acid composition in storage and membrane lipids showed a highly plastic response to temperature, but the responses of single fatty acids revealed deviations from the expectations based on HVA theory. We found an accumulation of C(18:2n6) and C(18:3n3) at higher temperatures and the preservation of C(20:4n6) across temperatures, which is contrary to the expectation of decreased unsaturation at higher temperatures. The thermal response of these fatty acids in O. cincta differed from the findings in other species, and therefore shows there is interspecific variation in how single fatty acids contribute to HVA. Future research should determine the consequences of such variation in terms of costs and benefits for the thermal performance of species.

  11. Shock Initiation of Energetic Materials at Different Initial Temperatures

    SciTech Connect

    Urtiew, P A; Tarver, C M

    2005-01-14

    Shock initiation is one of the most important properties of energetic materials, which must transition to detonation exactly as intended when intentionally shocked and not detonate when accidentally shocked. The development of manganin pressure gauges that are placed inside the explosive charge and record the buildup of pressure upon shock impact has greatly increased the knowledge of these reactive flows. This experimental data, together with similar data from electromagnetic particle velocity gauges, has allowed us to formulate the Ignition and Growth model of shock initiation and detonation in hydrodynamic computer codes for predictions of shock initiation scenarios that cannot be tested experimentally. An important problem in shock initiation of solid explosives is the change in sensitivity that occurs upon heating (or cooling). Experimental manganin pressure gauge records and the corresponding Ignition and Growth model calculations are presented for two solid explosives, LX-17 (92.5 % triaminotrinitrobenzene (TATB) with 7.5 % Kel-F binder) and LX-04 (85 % octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazine (HMX) with 15 % Viton binder) at several initial temperatures.

  12. Biodegradability of dispersed crude oil at two different temperatures.

    PubMed

    Venosa, A D; Holder, E L

    2007-05-01

    Laboratory experiments were initiated to study the biodegradability of oil after dispersants were applied. Two experiments were conducted, one at 20 degrees C and the other at 5 degrees C. In both experiments, only the dispersed oil fraction was investigated. Each experiment required treatment flasks containing 3.5% artificial seawater and crude oil previously dispersed by either Corexit 9500 or JD2000 at a dispersant-to-oil ratio of 1:25. Two different concentrations of dispersed oil were prepared, the dispersed oil then transferred to shake flasks, which were inoculated with a bacterial culture and shaken on a rotary shaker at 200 rpm for several weeks. Periodically, triplicate flasks were removed and sacrificed to determine the residual oil concentration remaining at that time. Oil compositional analysis was performed by gas chromatography/mass spectrometry (GC/MS) to quantify the biodegradability. Dispersed oil biodegraded rapidly at 20 degrees C and less rapidly at 5 degrees C, in line with the hypothesis that the ultimate fate of dispersed oil in the sea is rapid loss by biodegradation.

  13. Differences between near-surface equivalent temperature and temperature trends for the Eastern United States. Equivalent temperature as an alternative measure of heat content

    USGS Publications Warehouse

    Davey, C.A.; Pielke, R.A.; Gallo, K.P.

    2006-01-01

    There is currently much attention being given to the observed increase in near-surface air temperatures during the last century. The proper investigation of heating trends, however, requires that we include surface heat content to monitor this aspect of the climate system. Changes in heat content of the Earth's climate are not fully described by temperature alone. Moist enthalpy or, alternatively, equivalent temperature, is more sensitive to surface vegetation properties than is air temperature and therefore more accurately depicts surface heating trends. The microclimates evident at many surface observation sites highlight the influence of land surface characteristics on local surface heating trends. Temperature and equivalent temperature trend differences from 1982-1997 are examined for surface sites in the Eastern U.S. Overall trend differences at the surface indicate equivalent temperature trends are relatively warmer than temperature trends in the Eastern U.S. Seasonally, equivalent temperature trends are relatively warmer than temperature trends in winter and are relatively cooler in the fall. These patterns, however, vary widely from site to site, so local microclimate is very important. ?? 2006 Elsevier B.V. All rights reserved.

  14. Optimum dose variation caused by post exposure bake temperature difference inside photoresist over different sublayers and thickness

    NASA Astrophysics Data System (ADS)

    Kang, Young-Min; An, Ilsin; Kim, Do Wan; Oh, Hye-Keun

    2008-03-01

    In principle, the dose should not be changed to make the same linewidth if a perfect anti-reflection coating (ARC) is used for all the sublayers underneath the resist. However, the optimum dose for different sublayers and thicknesses are different even though perfect ARC is used. The post exposure bake (PEB) process of a chemically amplified resist is one of the key processes to make very small features of semiconductor device. The photo-generated acid makes the deprotection of protected polymer, and this deprotection highly depends on the PEB temperature and time. The diffusion length of acid is also strongly dependent on PEB temperature and time. As the linewidth of the device decreases, smaller diffusion length is required to reduce the roughness of the line edge and width. One of the key factors to determine the deprotection and acid diffusion is the initial temperature rising and the final real temperature inside the resist. The unpredictable temperature rising to the pre-set temperature mainly causes the variation of linewidth and the optimum dose. In order to predict the accurate PEB temperature and time dependency of the linewidth and dose, the heat transfer from the hot plate to the resist on the top of the multiply stacked sublayers over the silicon wafer has to be known since the reaction and diffusion occur inside the resist, not on the top of the bare silicon wafer. We studied heat transfer from the hot plate to the top of the resist including conductivity and thickness of each sublayer. For this purpose, a novel numerical approach incorporated with analytic method was proposed to solve the heat conduction problem. The unknowns for temperature are located only at the interfaces between layers, so that it is fast and efficient. We calculated the time that is consumed for the resist to attain the prescribed PEB temperature for the different multi stacks and thicknesses. Calculation shows that the temperature rising is different and final temperature on

  15. Comparison of models with different and identical vibrational temperatures of the molecular components

    NASA Astrophysics Data System (ADS)

    Shcherbak, V. G.

    1993-02-01

    Calculation results based on models with averaged and different vibrational temperatures of the molecular components are compared for flow near the critical line of the Buran spacecraft during its descent in the atmosphere. It is shown that the difference between the vibrational temperatures of molecular components may be substantial. When models with different vibrational temperatures are used, the effect of nonequilibrium excitation of vibrational degrees of freedom on the flow characteristics at the thermally stressed section of a gliding reentry trajectory is greater than in the case of a model with a single averaged vibrational temperature. The difference between the heat flows of the models can be as high as 20 percent.

  16. Influence of temperature difference on surface figure controlling during continuous polishing

    NASA Astrophysics Data System (ADS)

    Hong, Meijuan; Xu, Xueke; Dun, Aihuan; Yang, Minghong; Gao, Wenlan; Wei, Chaoyang; Liu, Shijie; Shao, Jianda; Zhang, Yang

    2015-08-01

    During continuous polishing, temperature is a significant source of processing uncertainty. Three work pieces of different kind material (K9, Nd:glass and ULE) were polished on 2.4m continuous polisher. It turns out that temperature difference has different influence on different material work pieces. It also indicates that temperature difference aggravates the processing uncertainy. The deformation caused by temperature difference is simulated using ANSYS. It shows that, with top-bottom temperature difference of 0.1°C, the deformation of Nd:glass, K9 and ULE are 0.444E-6 m (about 0.7025λ), 0.249E-6 m (about 0.3925λ ), and 0.105E-8 m (about 0.00166λ), respectively. With radial temperature difference of 0.1°C, the deformation of Nd:glass, K9 and ULE are 0.831E-7 m (about 0.1313λ), 0.465E-7 m (about 0.07348λ) and 0.196E-9 m (about 3.0973E-4λ), respectively. To explore the top-bottom temperature difference and radial temperature difference along the polishing surface, a small aperture Nd:glass and a large aperture Nd:glass in polishing have been measured using thermal infrared imager. The results showed that for Ø 260 mm × 26 mm Nd: glass, the radial temperature difference is about 0.1°C, while the top-bottom temperature difference is about 0.1°C ~ 0.21°C. Contrastively, for 810 mm×460 mm×40 mm Nd:glass, the radial temperature difference have reached 0.4°C, while top - bottom temperature difference ranges between 0.1°C ~ 0.27°C. When element gets larger, it will suffer greater temperature difference. These temperature differences are great enough to cause deformation far beyond the polishing accuracy required. Finally, methods are proposed to diminish the effect of temperature difference.

  17. Improving the Accuracy of Satellite Sea Surface Temperature Measurements by Explicitly Accounting for the Bulk-Skin Temperature Difference

    NASA Technical Reports Server (NTRS)

    Castro, Sandra L.; Emery, William J.

    2002-01-01

    The focus of this research was to determine whether the accuracy of satellite measurements of sea surface temperature (SST) could be improved by explicitly accounting for the complex temperature gradients at the surface of the ocean associated with the cool skin and diurnal warm layers. To achieve this goal, work centered on the development and deployment of low-cost infrared radiometers to enable the direct validation of satellite measurements of skin temperature. During this one year grant, design and construction of an improved infrared radiometer was completed and testing was initiated. In addition, development of an improved parametric model for the bulk-skin temperature difference was completed using data from the previous version of the radiometer. This model will comprise a key component of an improved procedure for estimating the bulk SST from satellites. The results comprised a significant portion of the Ph.D. thesis completed by one graduate student and they are currently being converted into a journal publication.

  18. Universal behavior of the viscosity of supercooled fragile and polymeric glassformers in different temperature regions

    NASA Astrophysics Data System (ADS)

    Andraca, Adriana; Goldstein, Patricia; del Castillo, Luis Felipe

    2016-11-01

    The behavior of the viscosity of supercooled liquids with temperature has been extensively studied in different regimes. We present a universal behavior for the Logarithmic Shift Factor for fragile and polymeric glassformers in two temperature regions, above and below the crossover temperature Tc, respectively. We find two different equations, one for each region, that may be represented as master plots which show universal behaviors for both cases.

  19. Effects of Different Environment Temperatures on Some Motor Characteristics and Muscle Strength

    ERIC Educational Resources Information Center

    Çakir, Ergün; Yüksek, Selami; Asma, Bülent; Arslanoglu, Erkal

    2016-01-01

    The aim of this study was determine the effects of different environment temperatures on motor characteristics and muscle strength. 15 athletes participated to study. Flexibility, vertical jump, hand grip-leg strength, 30m sprint, 20-meter shuttle run and coordination-agility tests were measured in five different environment temperatures. (22°C,…

  20. Thermoregulation responses of broiler chickens to humidity at different ambient temperatures. I. One week of age.

    PubMed

    Lin, H; Zhang, H F; Jiao, H C; Zhao, T; Sui, S J; Gu, X H; Zhang, Z Y; Buyse, J; Decuypere, E

    2005-08-01

    Three trials were conducted to investigate the effect of RH (35, 60, and 85%) on thermoregulation of 1-wk-old broiler chickens at different temperatures (35, 30, and 25 degrees C). The response to humidity in rectal temperature and plumage temperature at the back and breast within 24 h after exposure were recorded at 5 time points (1,4,8,16, and 24 h). Humidity affected the thermoregulation of 1-wk-old broiler chickens by redistributing heat within the body at high, low, and thermoneutral temperatures. The redistribution of heat resulted in decreased rectal temperature and increased peripheral temperature, which were, respectively, beneficial and unfavorable at high and low temperatures. These results suggested that feedback effects of surface temperature on core temperature also exist in poultry, as already observed in mammals, and could be induced not only by changed ambient temperature but also by the changes in humidity at high temperature. The disturbance of thermal equilibrium could not be established solely by changes in RT, but rather core and surface temperatures had to be considered. The daily rhythms in rectal and surface temperatures were affected by humidity.

  1. Differences induced by incubation temperature, versus androgen manipulation, in male leopard geckos (Eublepharis macularius).

    PubMed

    Huang, Victoria; Crews, David

    2012-08-20

    A fundamental tenet of sexual selection is that in sexually dimorphic traits, there is variation within a sex. In leopard geckos (Eublepharis macularius), a species with temperature-dependent sex determination, embryonic temperature contributes both to sex determination and polymorphisms within each sex. In this study we report that males from different incubation temperatures, one hitherto untested, exhibit significant differences in behavior even when castrated. Further, treatment with dihydrotestosterone increases scent marking, a territorial behavior. This supports previous results indicating that temperature has a direct organizing action on brain and sociosexual behavior independent of gonadal hormones.

  2. Temperature differences in the air layer close to a road surface

    NASA Astrophysics Data System (ADS)

    Bogren, Jörgen; Gustavsson, Torbjörn; Karlsson, Maria

    2001-12-01

    In this study, profiles of temperature and humidity (<250 cm above the road and 5 m into the surroundings) have been used to examine the development of temperature differences in the air layer close to the road. Temperature, humidity and wind profiles were measured, together with net radiation and observations of road surface state, at a test site at Road 45, Surte, Sweden. Measured temperature differences were compared with present weather, preceding weather, surface status, wind direction and other parameters thought to be important for the development of temperature differences. The results showed that large temperature differences (1-3 °C between 250 cm and 10 cm above the road) occurred when there was a high risk of slipperiness caused by hoarfrost, snow or ice on the road. The temperature differences between different levels were associated with the exchange of humidity and temperature between the air layer and the road surface. The 10 cm level reflected the surface processes well. Higher levels were influenced by the surroundings because of turbulence and advection. This study emphasises the need for measurements to be taken at a height and place that reflects the processes at the road surface.

  3. Clinical review: Brain-body temperature differences in adults with severe traumatic brain injury.

    PubMed

    Childs, Charmaine; Lunn, Kueh Wern

    2013-04-22

    Surrogate or 'proxy' measures of brain temperature are used in the routine management of patients with brain damage. The prevailing view is that the brain is 'hotter' than the body. The polarity and magnitude of temperature differences between brain and body, however, remains unclear after severe traumatic brain injury (TBI). The focus of this systematic review is on the adult patient admitted to intensive/neurocritical care with a diagnosis of severe TBI (Glasgow Coma Scale score of less than 8). The review considered studies that measured brain temperature and core body temperature. Articles published in English from the years 1980 to 2012 were searched in databases, CINAHL, PubMed, Scopus, Web of Science, Science Direct, Ovid SP, Mednar and ProQuest Dissertations & Theses Database. For the review, publications of randomised controlled trials, non-randomised controlled trials, before and after studies, cohort studies, case-control studies and descriptive studies were considered for inclusion. Of 2,391 records identified via the search strategies, 37 were retrieved for detailed examination (including two via hand searching). Fifteen were reviewed and assessed for methodological quality. Eleven studies were included in the systematic review providing 15 brain-core body temperature comparisons. The direction of mean brain-body temperature differences was positive (brain higher than body temperature) and negative (brain lower than body temperature). Hypothermia is associated with large brain-body temperature differences. Brain temperature cannot be predicted reliably from core body temperature. Concurrent monitoring of brain and body temperature is recommended in patients where risk of temperature-related neuronal damage is a cause for clinical concern and when deliberate induction of below-normal body temperature is instituted.

  4. An analysis of the differences between monitored indoor temperatures and reported thermostat settings

    SciTech Connect

    Vine, E.; Barnes, B.K.

    1988-03-01

    We examined differences in reported winter thermostat settings and monitored temperatures, and contrasted those households with little difference, and those with a substantial difference. This analysis was conducted on households participating in Bonneville Power Administration's Residential Standards Demonstration Program (RSDP) in the Pacific Northwest. The reported thermostat settings were obtained from a survey of RSDP participants, and indoor temperatures were read from special recorders inside the house. 9 refs., 5 figs., 4 tabs.

  5. Measurement of surface temperature and emissivity of different materials by two-colour pyrometry.

    PubMed

    Raj, Vinay C; Prabhu, S V

    2013-12-01

    An experimental investigation is performed to substantiate the capability of a charge coupled device camera to measure local temperature and emissivity of different materials heated to temperatures above 500 °C by two-colour pyrometric technique using colorimetric method. Materials investigated are Inconel 718 with pyromark (high temperature paint), Inconel 718, stainless steel SS 304 and SS 316. Centerline temperature and emissivity distribution is obtained for target plates maintained at constant temperature by AC heating while complete temperature and emissivity distribution is provided for plates heated by flame impingement. The obtained results are compared with a calibrated infrared camera and thermocouples and the temperature distribution is found to be in close agreement. These results pertain to partially oxidized metal alloys covered in this study. Deviation in the measurement of emissivity can be attributed to its dependence on wavelength range, oxidation, and sensitivity of the image detector.

  6. Prediction of air temperature in the aircraft cabin under different operational conditions

    NASA Astrophysics Data System (ADS)

    Volavý, F.; Fišer, J.; Nöske, I.

    2013-04-01

    This paper deals with the prediction of the air temperature in the aircraft cabin by means of Computational Fluid Dynamics. The simulations are performed on the CFD model which is based on geometry and cabin interior arrangement of the Flight Test Facility (FTF) located at Fraunhofer IBP, Germany. The experimental test flights under three different cabin temperatures were done in FTF and the various data were gathered during these flights. Air temperature in the cabin was measured on probes located near feet, torso and head of each passenger and also surface temperature and air temperature distributed from inlets were measured. The data were firstly analysed in order to obtain boundary conditions for cabin surfaces and inlets. Then the results of air temperature from the simulations were compared with measured data. The suitability and accuracy of the CFD approach for temperature prediction is discussed.

  7. Measurement of surface temperature and emissivity of different materials by two-colour pyrometry

    NASA Astrophysics Data System (ADS)

    Raj, Vinay C.; Prabhu, S. V.

    2013-12-01

    An experimental investigation is performed to substantiate the capability of a charge coupled device camera to measure local temperature and emissivity of different materials heated to temperatures above 500 °C by two-colour pyrometric technique using colorimetric method. Materials investigated are Inconel 718 with pyromark (high temperature paint), Inconel 718, stainless steel SS 304 and SS 316. Centerline temperature and emissivity distribution is obtained for target plates maintained at constant temperature by AC heating while complete temperature and emissivity distribution is provided for plates heated by flame impingement. The obtained results are compared with a calibrated infrared camera and thermocouples and the temperature distribution is found to be in close agreement. These results pertain to partially oxidized metal alloys covered in this study. Deviation in the measurement of emissivity can be attributed to its dependence on wavelength range, oxidation, and sensitivity of the image detector.

  8. Acclimation and acute temperature effects on population differences in oxidative phosphorylation.

    PubMed

    Baris, Tara Z; Crawford, Douglas L; Oleksiak, Marjorie F

    2016-01-15

    Temperature changes affect metabolism on acute, acclamatory, and evolutionary time scales. To better understand temperature's affect on metabolism at these different time scales, we quantified cardiac oxidative phosphorylation (OxPhos) in three Fundulus taxa acclimated to 12 and 28°C and measured at three acute temperatures (12, 20, and 28°C). The Fundulus taxa (northern Maine and southern Georgia F. heteroclitus, and a sister taxa, F. grandis) were used to identify evolved changes in OxPhos. Cardiac OxPhos metabolism was quantified by measuring six traits: state 3 (ADP and substrate-dependent mitochondrial respiration); E state (uncoupled mitochondrial activity); complex I, II, and IV activities; and LEAK ratio. Acute temperature affected all OxPhos traits. Acclimation only significantly affected state 3 and LEAK ratio. Populations were significantly different for state 3. In addition to direct effects, there were significant interactions between acclimation and population for complex I and between population and acute temperature for state 3. Further analyses suggest that acclimation alters the acute temperature response for state 3, E state, and complexes I and II: at the low acclimation temperature, the acute response was dampened at low assay temperatures, and at the high acclimation temperature, the acute response was dampened at high assay temperatures. Closer examination of the data also suggests that differences in state 3 respiration and complex I activity between populations were greatest between fish acclimated to low temperatures when assayed at high temperatures, suggesting that differences between the populations become more apparent at the edges of their thermal range.

  9. Acclimation and acute temperature effects on population differences in oxidative phosphorylation

    PubMed Central

    Baris, Tara Z.; Oleksiak, Marjorie F.

    2015-01-01

    Temperature changes affect metabolism on acute, acclamatory, and evolutionary time scales. To better understand temperature's affect on metabolism at these different time scales, we quantified cardiac oxidative phosphorylation (OxPhos) in three Fundulus taxa acclimated to 12 and 28°C and measured at three acute temperatures (12, 20, and 28°C). The Fundulus taxa (northern Maine and southern Georgia F. heteroclitus, and a sister taxa, F. grandis) were used to identify evolved changes in OxPhos. Cardiac OxPhos metabolism was quantified by measuring six traits: state 3 (ADP and substrate-dependent mitochondrial respiration); E state (uncoupled mitochondrial activity); complex I, II, and IV activities; and LEAK ratio. Acute temperature affected all OxPhos traits. Acclimation only significantly affected state 3 and LEAK ratio. Populations were significantly different for state 3. In addition to direct effects, there were significant interactions between acclimation and population for complex I and between population and acute temperature for state 3. Further analyses suggest that acclimation alters the acute temperature response for state 3, E state, and complexes I and II: at the low acclimation temperature, the acute response was dampened at low assay temperatures, and at the high acclimation temperature, the acute response was dampened at high assay temperatures. Closer examination of the data also suggests that differences in state 3 respiration and complex I activity between populations were greatest between fish acclimated to low temperatures when assayed at high temperatures, suggesting that differences between the populations become more apparent at the edges of their thermal range. PMID:26582639

  10. "study of Physical Properties of Carbon-Tetrachloride Mixture at Different Temperatures and Concentra Tions"

    NASA Astrophysics Data System (ADS)

    Adhikari, A. R.; Sah, C. S.; Bhattarai, P.

    2001-04-01

    The physical properties like ultrasonic velocity, density and refractive index has been measured for the binary mixture of Carbon Tetrachloride and Toluene at different temperatures (20°C-50°C). Parameters like isentropic compressibility (Ks), acoustic impedance (Z) and Rao-number (R) are also computed. It was observed that all parameters vary linearly with temperature within the range of concentration and temperature.

  11. Effect of diurnal temperature difference on lipid accumulation and development in Calanus sinicus (Copepoda: Calanoida)

    NASA Astrophysics Data System (ADS)

    Zhou, Konglin; Sun, Song

    2016-08-01

    Calanus sinicus, the dominant copepod in the Yellow Sea, develops a large oil sac in late spring to prepare for over-summering in the Yellow Sea Cold Water Mass (YSCWM). The lipid accumulation mechanism for the initiation of over-summering is unknown. Here, we cultured C3 copepodites at four constant temperatures (10, 13, 16, and 19°C) and at three temperature regimes that mimicked the temperature variations experienced during diurnal vertical migration (10-13°C, 10-16°C, and 10-19°C) for 18 days to explore the effects of temperature differences on copepod development and lipid accumulation. C. sinicus stored more lipid at low than at high temperatures. A diurnal temperature difference (10-16°C and 10-19°C) promoted greater lipid accumulation (1.9-2.1 times) than a constant temperature of either 16°C or 19°C, by reducing the energy cost at colder temperatures and lengthening copepodite development. Thereafter, the lipid reserve supported gonad development after final molting. Only one male developed in these experiments. This highly female-skewed sex ratio may have been the result of the monotonous microalgae diet fed to the copepodites. This study provides the first evidence that diurnal temperature differences may promote lipid accumulation in C. sinicus, and provides a foundation for future investigations into the mechanisms involved in over-summering in the YSCWM.

  12. Different mechanisms at different temperatures for the ring-opening polymerization of lactide catalyzed by binuclear magnesium and zinc alkoxides.

    PubMed

    Sun, Yangyang; Cui, Yaqin; Xiong, Jiao; Dai, Zhongran; Tang, Ning; Wu, Jincai

    2015-10-07

    Two binuclear magnesium and zinc alkoxides supported by a bis-salalen type dinucleating heptadentate Schiff base ligand were synthesized and fully characterized. The two complexes are efficient initiators for the ring-opening polymerization (ROP) of L-lactide, affording polymers with narrow polydispersities and desirable molecular weights. Interestingly, the mechanisms for the ROP of lactide are different at different temperatures. At a high temperature of 130 °C, a coordination-insertion mechanism is reasonable for the bulk melt polymerization of lactide. At a low temperature, the alkoxide cannot initiate the ROP reaction; however, upon the addition of external benzyl alcohol into the system, the ROP of lactide can smoothly proceed via an "activated monomer" mechanism. In addition, these complexes display slight stereo-selectivity for the ring-opening polymerization of rac-lactide, affording partially isotactic polylactide in toluene with a Pm value of 0.59.

  13. Atmospheric Circulation of Hot Jupiters: Dayside–Nightside Temperature Differences. II. Comparison with Observations

    NASA Astrophysics Data System (ADS)

    Komacek, Thaddeus D.; Showman, Adam P.; Tan, Xianyu

    2017-02-01

    The full-phase infrared light curves of low-eccentricity hot Jupiters show a trend of increasing fractional dayside–nightside brightness temperature difference with increasing incident stellar flux, both averaged across the infrared and in each individual wavelength band. The analytic theory of Komacek & Showman shows that this trend is due to the decreasing ability with increasing incident stellar flux of waves to propagate from day to night and erase temperature differences. Here, we compare the predictions of this theory with observations, showing that it explains well the shape of the trend of increasing dayside–nightside temperature difference with increasing equilibrium temperature. Applied to individual planets, the theory matches well with observations at high equilibrium temperatures but, for a fixed photosphere pressure of 100 {mbar}, systematically underpredicts the dayside–nightside brightness temperature differences at equilibrium temperatures less than 2000 {{K}}. We interpret this as being due to the effects of a process that moves the infrared photospheres of these cooler hot Jupiters to lower pressures. We also utilize general circulation modeling with double-gray radiative transfer to explore how the circulation changes with equilibrium temperature and drag strengths. As expected from our theory, the dayside–nightside temperature differences from our numerical simulations increase with increasing incident stellar flux and drag strengths. We calculate model phase curves using our general circulation models, from which we compare the broadband infrared offset from the substellar point and dayside–nightside brightness temperature differences against observations, finding that strong drag or additional effects (e.g., clouds and/or supersolar metallicities) are necessary to explain many observed phase curves.

  14. Effect of ultrasonic treatment of brown rice at different temperatures on cooking properties and quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This research aimed at developing quick cooking brown rice by investigating the effect of ultrasonic treatment at different temperatures on cooking time and quality. The medium grain brown rice was ultrasonically treated in water at temperatures of 25°C, 40°C and 55°C for 30 min and then dried by ai...

  15. Heat Resistance of Native and Demineralized Spores of Bacillus subtilis Sporulated at Different Temperatures

    PubMed Central

    Palop, Alfredo; Sala, Francisco J.; Condón, Santiago

    1999-01-01

    Demineralization reduced heat resistance of B. subtilis spores, but the pattern and magnitude of the reduction depended on sporulation temperature and on heating menstruum pH. The differences in heat resistance of native spores caused by sporulation temperature almost disappeared after demineralization. Demineralized spores were still susceptible to the heat-sensitizing effect of acidic pH. PMID:10049900

  16. Effects of different temperature regimens on the development of Aedes aegypti (L.) (Diptera: Culicidae) mosquitoes.

    PubMed

    Mohammed, Azad; Chadee, Dave D

    2011-07-01

    This study was conducted to determine the effects of increased water temperatures on the development of Aedes aegypti immatures under laboratory conditions in Trinidad, West Indies using temperature regulated water baths to cover a range of temperatures from 24-25°C to 34-35°C at a relative humidity of 80%. Two experiments were designed: (1) at constant temperature regimens and (2) under diurnal temperature regimens ranging from 24-25°C to 34-35°C. At 24-25°C egg hatching success was 98% at 48 h, however at 34-35°C egg hatching rates declined to 1.6% after 48 h. Ae. aegypti larvae reared under constant temperature regimens showed pupation on day 4 with highest pupation occurring at 30°C (78.4%) However, under diurnal temperature regimens, pupation began on day 4 but only at the higher temperatures of 30-35°C. Under diurnal temperature regimens ranging from 24°C to 35°C significantly more females emerged at higher temperatures, than males. In contrast, at constant temperatures of 24-35°C no significant difference in M/F ratios were observed. The body size of Ae. aegypti reared at constant temperature regimens was significantly larger than males and females larvae reared under diurnal temperature regimens of 25-30°C. The results of this study are discussed in the context of changing or increasing water temperatures, seasonal changes in vector populations and vector competence. Using these key factors control strategies are recommended to manage vector populations as expected increases in temperatures impact the Caribbean region.

  17. Each to their own: skeletal muscles of different function use different biochemical strategies during aestivation at high temperature.

    PubMed

    Young, Karen M; Cramp, Rebecca L; Franklin, Craig E

    2013-03-15

    Preservation of muscle morphology depends on a continuing regulatory balance between molecules that protect and molecules that damage muscle structural integrity. Excessive disruption of the biochemical balance that favours reactive oxygen species (ROS) in disused muscles may lead to oxidative stress, which in turn is associated with increased atrophic or apoptotic signalling and/or oxidative damage to the muscle and thus muscle disuse atrophy. Increases in the rate of oxygen consumption likely increase the overall generation of ROS in vivo. Temperature-induced increases in oxygen consumption rate occur in some muscles of ectotherms undergoing prolonged muscular disuse during aestivation. In the green-striped burrowing frog, Cyclorana alboguttata, both large jumping and small non-jumping muscles undergo atrophy seemingly commensurate with their rate of oxygen consumption during aestivation. However, because the extent of atrophy in these muscles is not enhanced at higher temperatures, despite a temperature-sensitive rate of oxygen consumption in the jumping muscle, we proposed that muscles are protected by biochemical means that, when mobilised at higher temperatures, inhibit atrophy. We proposed that the biochemical response to temperature would be muscle-specific. We examined the effect of temperature on the antioxidant and heat shock protein systems and determined the extent of oxidative damage to lipids and proteins in two functionally different skeletal muscles, the gastrocnemius (jumping muscle) and the iliofibularis (non-jumping muscle), by aestivating frogs at 24 and 30°C for 6 months. We assayed small molecule antioxidant capacity, mitochondrial and cytosolic superoxide dismutase activities and Hsp70 concentrations to show that protective mechanisms in disused muscles are differentially regulated with respect to both temperature and aestivation. High aestivation temperature results in an antioxidant response in the metabolically temperature

  18. Systematical electrochemical study on the parasitic shuttle-effect in lithium-sulfur-cells at different temperatures and different rates

    NASA Astrophysics Data System (ADS)

    Busche, Martin Rolf; Adelhelm, Philipp; Sommer, Heino; Schneider, Holger; Leitner, Klaus; Janek, Jürgen

    2014-08-01

    The influence of cycling rate and temperature on the performance of lithium sulfur batteries is systematically studied by evaluating data of hundred identical cells. Differences in the discharge and charge capacities and the voltage profiles during the first and subsequent cycles are evaluated quantitatively in detail. Special attention is paid to the parasitic shuttle effect and its magnitude as function of C-rate and temperature. Mathematical models by Kumaresan et al. and Mikhaylik et al. are used to discuss the correlation between discharge/charge capacities, cycling efficiency and cycling rate at different temperatures. Mathematical error analysis further provides information on typical deviations between identical samples that can be expected when characterizing Li/S cells. This error can become significant especially when reaching higher cycle numbers. When changing the cycling parameters we find that the different regions of the voltage profile are affected differently. Therefore, we conducted first galvanostatic intermittent titration technique (GITT) measurements on the Li/S cell system to study the kinetics during cell cycling and evaluated the relaxation behavior between the different states of discharge/charge and OCV conditions. Significant differences in relaxation kinetics are found for the lower and higher plateaus of the discharge- and charge voltage profiles.

  19. Temperature dependence of properties of Mn-doped nanocrystals with different binding symmetry

    NASA Astrophysics Data System (ADS)

    Yang, Boping; Zhao, Qing; Zhang, Jiayu

    2016-02-01

    We report the temperature dependence of photoluminescent properties of Mn-doped nanocrystals (NCs) with different binding symmetry. The photoluminescence peaks of Mn2+ ions shift to shorter wavelength with increasing temperatures, resulting from the reduction of crystal field. Further evidence for temperature-dependent crystal field variety is demonstrated by electronic paramagnetic resonance (EPR) spectra. Additionally, the inflexion temperature of the excited state lifetimes increases from 170 K (Sample I) to 220 K (Sample IV), which is speculated to be resulted from the easily affected wave function overlap due to thermal lattice expansion in more symmetrical binding Mn-doped NCs.

  20. Thermal equilibrium and temperature differences among body regions in European plethodontid salamanders.

    PubMed

    Lunghi, Enrico; Manenti, Raoul; Canciani, Giancarlo; Scarì, Giorgio; Pennati, Roberta; Ficetola, Gentile Francesco

    2016-08-01

    Information on species thermal physiology is extremely important to understand species responses to environmental heterogeneity and changes. Thermography is an emerging technology that allows high resolution and accurate measurement of body temperature, but until now it has not been used to study thermal physiology of amphibians in the wild. Hydromantes terrestrial salamanders are strongly depending on ambient temperature for their activity and gas exchanges, but information on their body temperature is extremely limited. In this study we tested if Hydromantes salamanders are thermoconform, we assessed whether there are temperature differences among body regions, and evaluated the time required to reach the thermal equilibrium. During summers of 2014 and 2015 we analysed 56 salamanders (Hydromantes ambrosii and Hydromantes italicus) using infrared thermocamera. We photographed salamanders at the moment in which we found them and 1, 2, 3, 4, 5 and 15min after having kept them in the hands. Body temperature was equal to air temperature; salamanders attained the equilibrium with air temperature in about 8min, the time required to reach equilibrium was longer in individuals with large body size. We detected small temperature differences between body parts, the head being slightly warmer than the body and the tail (mean difference: 0.05°C). These salamanders quickly reach the equilibrium with the environment, thus microhabitat measurement allows obtaining accurate information on their tolerance limits.

  1. MOVPE growth of laser structures for high-power applications at different ambient temperatures

    NASA Astrophysics Data System (ADS)

    Bugge, F.; Crump, P.; Frevert, C.; Knigge, S.; Wenzel, H.; Erbert, G.; Weyers, M.

    2016-10-01

    Laser structures for different operating temperatures were developed. Higher temperatures need an increase in barrier height to reduce carrier leakage. Best results for an emission wavelength of ≈800 nm were obtained using an asymmetric structure containing an n-InGaP and a p-Al0.5Ga0.5As waveguide. Such structures show 10 W output power for a single laser diode and >100 W for a laser bar at 50 °C ambient temperature and also a good aging behavior. Lower operating temperatures permit lower barrier heights which results in a lower series resistance and therefore higher conversion efficiency at high power. Carrier concentration and mobility for different AlxGa1-xAs compositions were estimated in dependence on temperature. An optimized structure reached 20 W for a single laser diode and 2 kW for a laser bar in QCW mode at -70 °C.

  2. Intricacies of using temperature of different niches for assessing impact on malaria transmission

    PubMed Central

    Singh, Poonam; Yadav, Yogesh; Saraswat, Shweta; Dhiman, Ramesh C.

    2016-01-01

    Background & objectives: The influence of temperature on the life cycle of mosquitoes as well as on development of malaria parasite in mosquitoes is well studied. Most of the studies use outdoor temperature for understanding the transmission dynamics and providing projections of malaria. As the mosquitoes breed in water and rest usually indoors, it is logical to relate the transmission dynamics with temperature of micro-niche. The present study was, therefore, undertaken to understand the influence of different formats of temperature of different micro-niches on transmission of malaria for providing more realistic projections. Methods: The study was conducted in one village each of Assam and Uttarakhand States of India. Temperatures recorded from outdoor (air) as well as indoor habitats (resting place of mosquito) were averaged into daily, fortnightly and monthly and were used for determination of transmission windows (TWs) for Plasmodium vivax (Pv) and P. falciparum (Pf) based on minimum temperature threshold required for transmission. Results: The daily temperature was found more useful for calculation of sporogony than fortnightly and monthly temperatures. Monthly TWs were further refined using fortnightly temperature, keeping in view the completion of more than one life cycle of malaria vectors and sporogony of malaria parasite in a month. A linear regression equation was generated to find out the relationship between outdoor and indoor temperatures and R2 to predict the percentage of variation in indoor temperature as a function of outdoor temperature at both localities. Interpretation & conclusions: The study revealed that the indoor temperature was more than outdoors in stable malarious area (Assam) but fluctuating in low endemic area like Uttarakhand. Transmission windows of malaria should be determined by transforming outdoor data to indoor and preferably at fortnightly interval. With daily recorded temperature, sporogonic and gonotrophic cycles can also

  3. Photosynthesis of young apple trees in response to low sink demand under different air temperatures.

    PubMed

    Fan, Pei G; Li, Lian S; Duan, Wei; Li, Wei D; Li, Shao H

    2010-03-01

    Gas exchange, chlorophyll fluorescence, photosynthetic end products and related enzymes in source leaves in response to low sink demand after girdling to remove the root sink were assessed in young apple trees (Malus pumila) grown in two greenhouses with different air temperatures for 5 days. Compared with the non-girdled control in the low-temperature greenhouse (diurnal maximum air temperature <32 degrees C), low sink demand resulted in lower net photosynthetic rate (P(n)), stomatal conductance (g(s)) and transpiration rate (E) but higher leaf temperature on Day 5, while in the high-temperature greenhouse (diurnal maximum air temperature >36 degrees C), P(n), g(s) and E declined from Day 3 onwards. Moreover, gas exchange responded more to low sink demand in the high-temperature greenhouse than in the low-temperature greenhouse. Decreased P(n) at low sink demand was accompanied by lower intercellular CO(2) concentrations in the low-temperature greenhouse. However, decreased maximal photochemical efficiency, potential activity, efficiency of excitation capture, actual efficiency and photochemical quenching, with increased minimal fluorescence and non-photochemical quenching of photosystem II (PSII), were observed in low sink demand leaves only in the high-temperature greenhouse. In addition, low sink demand increased leaf starch and soluble carbohydrate content in both greenhouses but did not result in lower activity of enzymes involved in metabolism. Thus, decreased P(n) under low sink demand was independent of a direct effect of end-product feedback but rather depended on a high temperature threshold. The lower P(n) was likely due to stomatal limitation in the low-temperature greenhouse, but mainly due to non-stomatal limitation in the high-temperature greenhouse.

  4. Tailoring biochars from different feedstock and produced at different temperature and time of pyrolysis for their use as soil amendments

    NASA Astrophysics Data System (ADS)

    Zornoza, Raul; Moreno, Fabian; Acosta, Jose A.; Gomez Lopez, Maria Dolores; Faz, Angel

    2015-04-01

    Biochar used as a soil amendment to improve soil quality and fertility and increase soil carbon sequestration has been the focus of much research in the recent past. Unlike most conventional soil organic materials, which are readily decomposed, the recalcitrant nature of biochar increases its potential value as a soil amending material for the longer term. However, many biochars can be hydrophobic, and added to soil can aggravate water availability in areas where water scarcity is a major limiting factor for agriculture or forestry. It has been shown that biochar characteristics are influenced by production variables, especially feedstock, pyrolysis temperature and time of pyrolysis. Although there have been different studies characterizing biochars prepared from different sources, there are few studies comparing different types of biochar produced from domestic residues, manures or crop residues pyrolysis; there are, in addition, fewer studies dealing with the hydrophobic properties of the biochars. The different feedstock can have different properties which would result into different biochars even produced at the same operational factors. The main objective of this experiment was to study the influence of feedstock properties and pyrolysis temperature and time on nutrient contents, heavy metals, recalcitrance, thermal stability and hydrophobicity of biochars from cotton crop residues (CR), pig manure (PM) and domestic waste (DW). Biochars were obtained by pyrolysis under oxygen-limited conditions in a muffle furnace. The temperature was increased at 5°C min-1 to 300°C, 400°C, 500°C and 700°C and then maintained for 1h, 2h, 4 and 5 h at this temperature. All biochar properties were strongly influenced by feedstock source except for pH, the recalcitrance index and hydrophobicity. Nutrient contents were normally higher in the PM biochar, except for Cu and Ca which were higher in the DW biochar and B in the CR biochar. Heavy metal contents were significantly

  5. Land Surface Temperature Measurements form EOS MODIS Data

    NASA Technical Reports Server (NTRS)

    Wan, Zhengming

    1996-01-01

    We have developed a physics-based land-surface temperature (LST) algorithm for simultaneously retrieving surface band-averaged emissivities and temperatures from day/night pairs of MODIS (Moderate Resolution Imaging Spectroradiometer) data in seven thermal infrared bands. The set of 14 nonlinear equations in the algorithm is solved with the statistical regression method and the least-squares fit method. This new LST algorithm was tested with simulated MODIS data for 80 sets of band-averaged emissivities calculated from published spectral data of terrestrial materials in wide ranges of atmospheric and surface temperature conditions. Comprehensive sensitivity and error analysis has been made to evaluate the performance of the new LST algorithm and its dependence on variations in surface emissivity and temperature, upon atmospheric conditions, as well as the noise-equivalent temperature difference (NE(Delta)T) and calibration accuracy specifications of the MODIS instrument. In cases with a systematic calibration error of 0.5%, the standard deviations of errors in retrieved surface daytime and nighttime temperatures fall between 0.4-0.5 K over a wide range of surface temperatures for mid-latitude summer conditions. The standard deviations of errors in retrieved emissivities in bands 31 and 32 (in the 10-12.5 micrometer IR spectral window region) are 0.009, and the maximum error in retrieved LST values falls between 2-3 K. Several issues related to the day/night LST algorithm (uncertainties in the day/night registration and in surface emissivity changes caused by dew occurrence, and the cloud cover) have been investigated. The LST algorithms have been validated with MODIS Airborne Simulator (MAS) dada and ground-based measurement data in two field campaigns conducted in Railroad Valley playa, NV in 1995 and 1996. The MODIS LST version 1 software has been delivered.

  6. Improving the Accuracy of Satellite Sea Surface Temperature Measurements by Explicitly Accounting for the Bulk-Skin Temperature Difference

    NASA Technical Reports Server (NTRS)

    Wick, Gary A.; Emery, William J.; Castro, Sandra L.; Lindstrom, Eric (Technical Monitor)

    2002-01-01

    The focus of this research was to determine whether the accuracy of satellite measurements of sea surface temperature (SST) could be improved by explicitly accounting for the complex temperature gradients at the surface of the ocean associated with the cool skin and diurnal warm layers. To achieve this goal, work was performed in two different major areas. The first centered on the development and deployment of low-cost infrared radiometers to enable the direct validation of satellite measurements of skin temperature. The second involved a modeling and data analysis effort whereby modeled near-surface temperature profiles were integrated into the retrieval of bulk SST estimates from existing satellite data. Under the first work area, two different seagoing infrared radiometers were designed and fabricated and the first of these was deployed on research ships during two major experiments. Analyses of these data contributed significantly to the Ph.D. thesis of one graduate student and these results are currently being converted into a journal publication. The results of the second portion of work demonstrated that, with presently available models and heat flux estimates, accuracy improvements in SST retrievals associated with better physical treatment of the near-surface layer were partially balanced by uncertainties in the models and extra required input data. While no significant accuracy improvement was observed in this experiment, the results are very encouraging for future applications where improved models and coincident environmental data will be available. These results are included in a manuscript undergoing final review with the Journal of Atmospheric and Oceanic Technology.

  7. The large volcanic eruptions at different latitude bands and patterns of winter temperature changes over China

    NASA Astrophysics Data System (ADS)

    Hao, Zhixin; Sun, Di

    2016-04-01

    Based on the chronology of 29 large volcanic eruptions events (Volcanic Explosivity Index≥4) since 1951 and gridded temperature dataset from China Meteorological Data Sharing Service System, we identified the patterns of winter temperature changes over China after the large volcanic eruptions, comparing with the mean temperature within the five years before, then we analyzed the related dynamic mechanisms of different patterns by NCEP reanalysis data and model output data from Community Earth System Model (CESM). The results showed that the winter temperature decreased more than 1°C in East China after volcanic eruptions on middle-lower latitudes and equatorial bands. After volcanic eruptions on different latitudes, the temperature spatial patterns were summarized as two types, which included that temperature was cooling centered on Northeast and warming in Tibets, and its opposite pattern. The first pattern was usually detected after tropical volcanic eruptions in spring/summer and it also appeared after volcanic eruptions on high latitudes in spring/autumn. After middle-lower latitude volcanic eruptions, the variation of geopotential height on 500hPa showed that the positive anomaly was existed at the East of Ural mountain, which caused the temperature decreased in Northwest , Central East and Southeast when east asian trough was intensified. After high latitudes volcanic eruptions, the zonal circulation was more obvious at middle latitudes, the cold air was not easy to transport,therefore winter temperature increased in China except for the Yangtze River Basin. The result of full forcing experiments by CESM showed that temperature decreased at most regions after large volcanic eruptions on equatorial /high bands, and troughs and wedges were developed on 500 hPa. The variation of geopotential height was nearly reversed after volcanic eruptions on high latitudes, only the temperature of Tibetan Plateau decreased. But how the variation of geopotential height

  8. The large volcanic eruptions at different latitude bands and patterns of winter temperature changes over China

    NASA Astrophysics Data System (ADS)

    Sun, D.; Hao, Z.; Zheng, J.

    2015-12-01

    Based on the chronology of 29 large volcanic eruptions events (Volcanic Explosivity Index≥4) since 1951 and gridded temperature dataset from China Meteorological Data Sharing Service System, we identified the patterns of winter temperature changes over China after the large volcanic eruptions, comparing with the mean temperature within the five years before, then we analyzed the related dynamic mechanisms of different patterns by NCEP reanalysis data and model output data from Community Earth System Model (CESM). The results showed that the winter temperature decreased more than 1°C in East China after volcanic eruptions on middle-lower latitudes and equatorial bands. After volcanic eruptions on different latitudes, the temperature spatial patterns were summarized as two types, which included that temperature was cooling centered on Northeast and warming in Tibets, and its opposite pattern. The first pattern was usually detected after equatorial volcanic eruptions in spring/summer and it also appeared after volcanic eruptions on high latitudes in spring/autumn. After middle-lower latitude volcanic eruptions, the variation of geopotential height on 500hPa showed that the positive anomaly was existed at the East of Ural mountain, which caused the temperature decreased in Northwest , Central East and Southeast when east asian trough was intensified. After high latitudes volcanic eruptions, the zonal circulation was more obvious at middle latitudes, the cold air was not easy to transport therefore winter temperature increased in China except for the Yangtze River Basin. The result of full forcing experiments by CESM showed that temperature decreased at most regions after large volcanic eruptions on equatorial /high bands, and troughs and wedges were developed on 500 hPa. The variation of geopotential height was nearly reversed after volcanic eruptions on high latitudes, only the temperature of Tibetan Plateau decreased. But how the variation of geopotential height

  9. Cloacal and surface temperatures of tom turkeys exposed to different rearing temperature regimes during the first 12 weeks of growth.

    PubMed

    Mayes, S L; Strawford, M L; Noble, S D; Classen, H L; Crowe, T G

    2015-06-01

    Years of genetic selection have caused an increase in growth rate and market body mass in agricultural poultry species compared to earlier genetic strains, potentially altering their physiological requirements. The objective of this study was to expose Hybrid Converter tom turkeys on a weekly basis to the recommended rearing temperature regime (TCON: control) or 4°C below the recommended standard (TTRT: treatment) to determine their thermal responses. Once per week for 12 weeks, 12 turkeys were individually exposed to either TCON or TTRT for a 2-h period. Surface temperatures of the breast (TBREAST), wing (TWING), drumstick (TDRUM), head (THEAD), and shank (TSHANK) were measured at 20-min intervals using an infrared camera, while a thermal data logger measured the skin surface temperature under the wing (TLOGGER) at 30-s intervals. The cloacal temperature (TCORE) was measured using a medical thermometer at the start and end of the exposure period. Regardless of exposure temperature, the TBREAST (TCON: P<0.001 and TTRT: P<0.001), TWING (TCON: P<0.001 and TTRT: P<0.001), and TDRUM (TCON: P<0.001 and TTRT: P<0.001) decreased from weeks 4 to 6 and remained constant from weeks 1 to 3 and 8 to 12. THEAD was elevated in week 2 (TCON: P<0.001) or week 3 (TTRT: P<0.001), TSHANK increased slightly during week 3 for both TCON (P<0.001) and TTRT (P<0.001), and TLOGGER (TCON: P<0.001 and TTRT: P=0.001) and TCORE (TCON: P<0.001 and TTRT: P<0.001) were lower during the first week. Thereafter, THEAD, TSHANK, TLOGGER, and TCORE remained constant. Exposure to TTRT resulted in lower TBREAST, TWING, and TDRUM compared to TCON. Generally, THEAD, TSHANK, TLOGGER, and TCORE were not affected by the different exposure temperatures. The data demonstrated that the degree of thermal response expressed is dependent on the location of measurement, age, and exposure temperature.

  10. Alteration of protein patterns in black rock inhabiting fungi as a response to different temperatures

    PubMed Central

    Tesei, Donatella; Marzban, Gorji; Zakharova, Kristina; Isola, Daniela; Selbmann, Laura; Sterflinger, Katja

    2012-01-01

    Rock inhabiting fungi are among the most stress tolerant organisms on Earth. They are able to cope with different stressors determined by the typical conditions of bare rocks in hot and cold extreme environments. In this study first results of a system biological approach based on two-dimensional protein profiles are presented. Protein patterns of extremotolerant black fungi – Coniosporium perforans, Exophiala jeanselmei – and of the extremophilic fungus – Friedmanniomyces endolithicus – were compared with the cosmopolitan and mesophilic hyphomycete Penicillium chrysogenum in order to follow and determine changes in the expression pattern under different temperatures. The 2D protein gels indicated a temperature dependent qualitative change in all the tested strains. Whereas the reference strain P. chrysogenum expressed the highest number of proteins at 40 °C, thus exhibiting real signs of temperature induced reaction, black fungi, when exposed to temperatures far above their growth optimum, decreased the number of proteins indicating a down-regulation of their metabolism. Temperature of 1 °C led to an increased number of proteins in all of the analysed strains, with the exception of P. chrysogenum. These first results on temperature dependent reactions in rock inhabiting black fungi indicate a rather different strategy to cope with non-optimal temperature than in the mesophilic hyphomycete P. chrysogenum. PMID:22862921

  11. Temperature change and hardness with different resin composites and photo-activation methods.

    PubMed

    Schneider, Luis Felipe Jochims; Consani, Simonides; Sinhoreti, Mário Alexandre Coelho; Sobrinho, Lourenço Correr; Milan, Fábio Machado

    2005-01-01

    This study verifies whether there is any temperature change during photoactivation of two resin composites (Filtek Z250 and Filtek Flow) with three different light curing methods (conventional halogen light curing unit, light emitting diodes curing unit and xenon plasma arc curing unit) and the relationship of temperature change with resin composite hardness. A type-K thermocouple registered the temperature rise peak in an elastomer mold during photoactivation. After photoactivation, the specimens were submitted to Knoop hardness test performed by an indenter (HMV-2000) under a load of 50g for 15 seconds. Both the temperature change data and results of the Knoop hardness test were submitted to ANOVA and Tukey's test at the 5% significance level. No statistical differences in temperature rise were recorded for the different composites following processing by light curing unit (p>0.05). The conventional halogen source produced statistically higher temperatures (p<0.05) than the other units. The plasma arc source promoted statistically lower (p<0.05) Knoop hardness values and temperature changes than the other light curing units.

  12. Alteration of protein patterns in black rock inhabiting fungi as a response to different temperatures.

    PubMed

    Tesei, Donatella; Marzban, Gorji; Zakharova, Kristina; Isola, Daniela; Selbmann, Laura; Sterflinger, Katja

    2012-08-01

    Rock inhabiting fungi are among the most stress tolerant organisms on Earth. They are able to cope with different stressors determined by the typical conditions of bare rocks in hot and cold extreme environments. In this study first results of a system biological approach based on two-dimensional protein profiles are presented. Protein patterns of extremotolerant black fungi -Coniosporium perforans, Exophiala jeanselmei - and of the extremophilic fungus -Friedmanniomyces endolithicus - were compared with the cosmopolitan and mesophilic hyphomycete Penicillium chrysogenum in order to follow and determine changes in the expression pattern under different temperatures. The 2D protein gels indicated a temperature dependent qualitative change in all the tested strains. Whereas the reference strain P. chrysogenum expressed the highest number of proteins at 40 °C, thus exhibiting real signs of temperature induced reaction, black fungi, when exposed to temperatures far above their growth optimum, decreased the number of proteins indicating a down-regulation of their metabolism. Temperature of 1 °C led to an increased number of proteins in all of the analysed strains, with the exception of P. chrysogenum. These first results on temperature dependent reactions in rock inhabiting black fungi indicate a rather different strategy to cope with non-optimal temperature than in the mesophilic hyphomycete P. chrysogenum.

  13. Electron temperature difference between the o-point and x-point of a magnetic island

    SciTech Connect

    Yang Jinhong; Zhu Sizheng; Yu Qingquan; Zhuang, G.

    2009-09-15

    The electron temperature difference between the o-point and the x-point of a magnetic island is studied numerically by solving the two-dimensional energy transport equation. It is found that, even without a localized radio-frequency heating at the island's o-point, there is usually a temperature difference between these two points. This difference depends on the radial profile of the heating power deposition, the ratio between the parallel and the perpendicular heat conductivity and the island width, and it takes a minimum when the island width is about twice the local heat diffusion layer width. The effect of the temperature difference on the island growth is further studied, and the peaked heating power density profile at magnetic axis is found be destabilizing.

  14. The shift of thermoneutral zone in striped hamster acclimated to different temperatures.

    PubMed

    Zhao, Zhi-Jun; Chi, Qing-Sheng; Liu, Quan-Sheng; Zheng, Wei-Hong; Liu, Jin-Song; Wang, De-Hua

    2014-01-01

    Temperature affects all biological functions and will therefore modulate ecologically significant interactions between animals and their environment. Here, we examined the effect of ambient temperature (Ta) on the thermal biology and energy budget in striped hamsters acclimated to cold (5°C), warm (21°C) and hot temperatures (31°C). Thermoneutral zone (TNZ) was 22.5-32.5°C, 25-32.5°C and 30-32.5°C in the cold-, warm- and hot-acclimated hamsters, respectively. The cold acclimation decreased the lower critical temperature and made the TNZ wider, and hot exposure elevated the lower critical temperature, resulting in a narrow TNZ. Within the TNZ, cold-acclimated hamsters showed a significantly higher rate of metabolism and thermogenesis than those acclimated to hot temperature. Digestive enzymes activities, including intestinal sucrase, maltase, L-alanine aminopeptidase-N and leucine aminopeptidase were higher in the cold than in the hot. The changes in metabolic rate and thermogenesis at different temperatures were in parallel with cytochrome c oxidase activity and uncoupling protein 1 gene expression of brown adipose tissue. This suggests that the shift of the lower critical temperature of TNZ is possibly associated with the rate of metabolism and thermogenesis, as well as with the digestive capacity of the gastrointestinal tract at different Ta. The upper critical temperature of TNZ may be independent of the changes in Ta. The changes of lower critical temperature of TNZ are an important strategy in adaption to variations of Ta.

  15. Temperature Profiles Along the Root with Gutta-percha Warmed through Different Heat Sources

    PubMed Central

    Simeone, Michele; Santis, Roberto De; Ametrano, Gianluca; Prisco, Davide; Borrelli, Marino; Paduano, Sergio; Riccitiello, Francesco; Spagnuolo, Gianrico

    2014-01-01

    Objectives: To evaluate temperature profiles developing in the root during warm compaction of gutta-percha with the heat sources System B and System MB Obtura (Analityc Technology, Redmond, WA, USA). Thirty extracted human incisor teeth were used. Root canals were cleaned and shaped by means of Protaper rotary files (Dentsply-Maillefer, Belgium), and imaging was performed by micro-CT (Skyscan 1072, Aartselaar, Belgium). Methods: Teeth were instrumented with K-type thermocouples, and the roots were filled with thermoplastic gutta-percha. Vertical compaction was achieved through the heat sources System B and System MB, and temperature profiles were detect-ed by means of NI Dac Interface controlled by the LabView System. With both heat sources, higher temperature levels were recorded in the region of the root far from the apex. When the warm plugger tip was positioned at a distance of 3 mm from the root apex, temperature levels of about 180°C were used to soften gutta-percha, and no statistically significant differences were observed between peak temperatures developed by the two heating sources at the root apex. However, a temperature level higher than 40°C was maintained for a longer time with System MB. Results: Statistically significant differences were observed in peak temperature levels recorded far from the root apex. Thus, with a temperature of about 180°C and the warm plugger positioned at 3 mm from the root apex, both heating sources led to a temperature slightly higher than 40°C at the apex of the root, suggesting that the gutta-percha was properly softened. Significance: A temperature level higher than 40°C was maintained for a longer time with System MB, thus providing an ad-equate time for warm compaction of the gutta-percha. PMID:25614768

  16. The Shift of Thermoneutral Zone in Striped Hamster Acclimated to Different Temperatures

    PubMed Central

    Zhao, Zhi-Jun; Chi, Qing-Sheng; Liu, Quan-Sheng; Zheng, Wei-Hong; Liu, Jin-Song; Wang, De-Hua

    2014-01-01

    Temperature affects all biological functions and will therefore modulate ecologically significant interactions between animals and their environment. Here, we examined the effect of ambient temperature (Ta) on the thermal biology and energy budget in striped hamsters acclimated to cold (5°C), warm (21°C) and hot temperatures (31°C). Thermoneutral zone (TNZ) was 22.5–32.5°C, 25–32.5°C and 30–32.5°C in the cold-, warm- and hot-acclimated hamsters, respectively. The cold acclimation decreased the lower critical temperature and made the TNZ wider, and hot exposure elevated the lower critical temperature, resulting in a narrow TNZ. Within the TNZ, cold-acclimated hamsters showed a significantly higher rate of metabolism and thermogenesis than those acclimated to hot temperature. Digestive enzymes activities, including intestinal sucrase, maltase, L-alanine aminopeptidase-N and leucine aminopeptidase were higher in the cold than in the hot. The changes in metabolic rate and thermogenesis at different temperatures were in parallel with cytochrome c oxidase activity and uncoupling protein 1 gene expression of brown adipose tissue. This suggests that the shift of the lower critical temperature of TNZ is possibly associated with the rate of metabolism and thermogenesis, as well as with the digestive capacity of the gastrointestinal tract at different Ta. The upper critical temperature of TNZ may be independent of the changes in Ta. The changes of lower critical temperature of TNZ are an important strategy in adaption to variations of Ta. PMID:24400087

  17. Effects of inherent alkali and alkaline earth metallic species on biomass pyrolysis at different temperatures.

    PubMed

    Hu, Song; Jiang, Long; Wang, Yi; Su, Sheng; Sun, Lushi; Xu, Boyang; He, Limo; Xiang, Jun

    2015-09-01

    This work aimed to investigate effects of inherent alkali and alkaline earth metallic species (AAEMs) on biomass pyrolysis at different temperatures. The yield of CO, H2 and C2H4 was increased and that of CO2 was suppressed with increasing temperature. Increasing temperature could also promote depolymerization and aromatization reactions of active tars, forming heavier polycyclic aromatic hydrocarbons, leading to decrease of tar yields and species diversity. Diverse performance of inherent AAEMs at different temperatures significantly affected the distribution of pyrolysis products. The presence of inherent AAEMs promoted water-gas shift reaction, and enhanced the yield of H2 and CO2. Additionally, inherent AAEMs not only promoted breakage and decarboxylation/decarbonylation reaction of thermally labile hetero atoms of the tar but also enhanced thermal decomposing of heavier aromatics. Inherent AAEMs could also significantly enhance the decomposition of levoglucosan, and alkaline earth metals showed greater effect than alkali metals.

  18. Non-Newtonian Characteristics of Gochujang and Chogochujang at Different Temperatures

    PubMed Central

    Choi, Ji Eun; Lee, Jun Ho

    2017-01-01

    This study was conducted to determine the rheological properties of gochujang and chogochujang at different temperatures (25, 35, and 45°C). Rheological properties of the samples were determined using a rotational rheometer at a shear range of 1 to 40 s−1. Gochujang and chogochujang were found to be non-Newtonian fluids according to the Herschel-Bulkley model. Yield stress and consistency coefficient of gochujang at different temperatures were higher than those of chogochujang, whereas the opposite was observed for flow behavior index. Moreover, all rheological properties of gochujang and chogochujang decreased with increasing temperature. The consistency coefficient was related to temperature using an Arrhenius-type relationship. Gochujang (14.48 kJ/mol) had slightly higher activation energy than chogochujang (14.03 kJ/mol).

  19. Temperature measurements with two different IR sensors in a continuous-flow microwave heated system

    PubMed Central

    Rydfjord, Jonas; Svensson, Fredrik; Fagrell, Magnus; Sävmarker, Jonas; Thulin, Måns

    2013-01-01

    Summary In a continuous-flow system equipped with a nonresonant microwave applicator we have investigated how to best assess the actual temperature of microwave heated organic solvents with different characteristics. This is non-trivial as the electromagnetic field will influence most traditional methods of temperature measurement. Thus, we used a microwave transparent fiber optic probe, capable of measuring the temperature inside the reactor, and investigated two different IR sensors as non-contact alternatives to the internal probe. IR sensor 1 measures the temperature on the outside of the reactor whilst IR sensor 2 is designed to measure the temperature of the fluid through the borosilicate glass that constitutes the reactor wall. We have also, in addition to the characterization of the before mentioned IR sensors, developed statistical models to correlate the IR sensor reading to a correct value of the inner temperature (as determined by the internal fiber optic probe), thereby providing a non-contact, indirect, temperature assessment of the heated solvent. The accuracy achieved with these models lie well within the range desired for most synthetic chemistry applications. PMID:24204419

  20. Temperature of denture base resin under different protocols of microwave irradiation.

    PubMed

    Sesma, Newton; Gil, Carlos; Kolikauskas, William Antunes; Silva, Rafael Andrade; Pannuti, Claudio Mendes

    2011-01-01

    This in vitro study evaluated the temperature of dentures after different microwave irradiation protocols. Two complete dentures (one maxillary and one mandibular denture) were irradiated separately 4 times for each of the following 5 protocols: dentures immersed in water (G1- 6 min, G2- 3 min); dentures kept dry (G3- 6 min); dentures placed in the steam sterilizer (G4- 6 min, G5- 3 min). The final temperature of the dentures was gauged in a thin and in a thick area of each denture with an infrared thermometer. All groups presented an increase in the resin base temperature. The thin areas of the dentures underwent greater heating than the thick areas. There was no significant difference (p>0.05) between the final mean temperatures of dentures immersed in water for 6 (G1) and 3 min (G2). However, the final mean temperatures recorded in G1 and G2 exceeded 71°C and were significantly higher (<0.001) than the final mean temperatures recorded in the other groups. It may be concluded that denture base resins subjected to microwave irradiation immersed in water may be exposed to deleterious temperatures.

  1. Temperature measurements with two different IR sensors in a continuous-flow microwave heated system.

    PubMed

    Rydfjord, Jonas; Svensson, Fredrik; Fagrell, Magnus; Sävmarker, Jonas; Thulin, Måns; Larhed, Mats

    2013-01-01

    In a continuous-flow system equipped with a nonresonant microwave applicator we have investigated how to best assess the actual temperature of microwave heated organic solvents with different characteristics. This is non-trivial as the electromagnetic field will influence most traditional methods of temperature measurement. Thus, we used a microwave transparent fiber optic probe, capable of measuring the temperature inside the reactor, and investigated two different IR sensors as non-contact alternatives to the internal probe. IR sensor 1 measures the temperature on the outside of the reactor whilst IR sensor 2 is designed to measure the temperature of the fluid through the borosilicate glass that constitutes the reactor wall. We have also, in addition to the characterization of the before mentioned IR sensors, developed statistical models to correlate the IR sensor reading to a correct value of the inner temperature (as determined by the internal fiber optic probe), thereby providing a non-contact, indirect, temperature assessment of the heated solvent. The accuracy achieved with these models lie well within the range desired for most synthetic chemistry applications.

  2. Momentum and mass fluxes in a gas confined between periodically structured surfaces at different temperatures

    NASA Astrophysics Data System (ADS)

    Donkov, Alexander A.; Tiwari, Sudarshan; Liang, Tengfei; Hardt, Steffen; Klar, Axel; Ye, Wenjing

    2011-07-01

    It is well known that in a gas-filled duct or channel along which a temperature gradient is applied, a thermal creep flow is created. Here we show that a mass and momentum flux can also be induced in a gas confined between two parallel structured surfaces at different temperatures, i.e., orthogonal to the temperature gradient. We use both analytical and numerical methods to compute the resulting fluxes. The momentum flux assumes its maximum value in the free-molecular flow regime, the (normalized) mass flux in the transition flow regime. The discovered phenomena could find applications in methods for energy-conversion and thermal pumping of gases.

  3. Temperature Characterization of Different Urban Microhabitats of Aedes albopictus (Diptera Culicidae) in Central-Northern Italy.

    PubMed

    Vallorani, Roberto; Angelini, Paola; Bellini, Romeo; Carrieri, Marco; Crisci, Alfonso; Mascali Zeo, Silvia; Messeri, Gianni; Venturelli, Claudio

    2015-08-01

    Aedes albopictus (Skuse) is an invasive mosquito species that has spread to many countries in temperate regions bordering the Mediterranean basin, where it is becoming a major public health concern. A good knowledge of the thermal features of the most productive breeding sites for Ae. albopictus is crucial for a better estimation of the mosquitoes' life cycle and developmental rates. In this article, we address the problem of predicting air temperature in three microhabitats common in urban and suburban areas and the air and water temperature inside an ordinary catch basin, which is considered the most productive breeding site for Ae. albopictus in Italy. Temperature differences were statistically proven between the three microhabitats and between the catch basin external and internal temperature. The impacts on the developmental rates for each life stage of Ae. albopictus were tested through a parametric function of the temperature, and the aquatic stages resulted as being the most affected using the specific temperature inside a typical catch basin instead of a generic air temperature. The impact of snow cover on the catch basin internal temperature, and consequently on the mortality of diapausing eggs, was also evaluated. These data can be useful to improve epidemiological models for a better prediction of Ae. albopictus seasonal and population dynamics in central-northern Italian urban areas.

  4. Nonlinear optical parameters of nanocrystalline AZO thin film measured at different substrate temperatures

    NASA Astrophysics Data System (ADS)

    Jilani, Asim; Abdel-wahab, M. Sh; Al-ghamdi, Attieh A.; Dahlan, Ammar sadik; Yahia, I. S.

    2016-01-01

    The 2.2 wt% of aluminum (Al)-doped zinc oxide (AZO) transparent and preferential c-axis oriented thin films were prepared by using radio frequency (DC/RF) magnetron sputtering at different substrate temperature ranging from room temperature to 200 °C. For structural analysis, X-ray Diffraction (XRD) and Atomic Force Electron Microscope (AFM) was used for morphological studies. The optical parameters such as, optical energy gap, refractive index, extinction coefficient, dielectric loss, tangent loss, first and third order nonlinear optical properties of transparent films were investigated. High transmittance above 90% and highly homogeneous surface were observed in all samples. The substrate temperature plays an important role to get the best transparent conductive oxide thin films. The substrate temperature at 150 °C showed the growth of highly transparent AZO thin film. Energy gap increased with the increased in substrate temperature of Al doped thin films. Dielectric constant and loss were found to be photon energy dependent with substrate temperature. The change in substrate temperature of Al doped thin films also affect the non-liner optical properties of thin films. The value of χ(3) was found to be changed with the grain size of the thin films that directly affected by the substrate temperature of the pure and Al doped ZnO thin films.

  5. Compensatory growth of juvenile brown flounder Paralichthys olivaceus following low temperature treatment for different periods

    NASA Astrophysics Data System (ADS)

    Peng, Yinhui; Liu, Xiujia; Huang, Guoqiang; Wei, Liuzhi; Zhang, Xiumei

    2017-04-01

    We investigated the effects of low temperature (8.5°C) on the growth and feeding rates and feed conversion efficiency of juvenile P. olivaceus with an average initial weight of 3.87 ± 0.06 g (mean ± SE). Fish were exposed to 8.5°C for 0 (control), 1, 2, 3 and 4 weeks, and then to 20°C for 10, 9, 8, 7 and 6 weeks, respectively. Low temperature clearly led to growth depression. The weight of fish exposed to low temperature for 1 week was restored to that of control, while that of fish exposed to low temperature longer was significantly decreased ( P < 0.05). During the entire low-temperature period, specific growth rate, feeding rate and feed conversion efficiency of the fish were significantly lower ( P < 0.05) than those of control, while in the whole recovery period, specific growth and average feeding rate were markedly higher ( P < 0.05) than those of control. At the end of experiment, only the feeding rate of the fish exposed to low temperature for 1 week was not significantly different from that of control ( P > 0.05). Feeding rate and feed conversion efficiency were reduced at low temperature in juvenile P. olivaceus. The compensatory growth of juvenile P. olivaceus may therefore be attributed to the improvement of feeding rate. Our results suggested that growth depression occurs when juvenile P. olivaceus are exposed to low temperature for more than one week.

  6. Feel the heat: activation, orientation and feeding responses of bed bugs to targets at different temperatures.

    PubMed

    DeVries, Zachary C; Mick, Russell; Schal, Coby

    2016-12-01

    Host location in bed bugs is poorly understood. Of the primary host-associated cues known to attract bed bugs - CO2, odors, heat - heat has received little attention as an independent stimulus. We evaluated the effects of target temperatures ranging from 23 to 48°C on bed bug activation, orientation and feeding. Activation and orientation responses were assessed using a heated target in a circular arena. All targets heated above ambient temperature activated bed bugs (initiated movement) and elicited oriented movement toward the target, with higher temperatures generally resulting in faster activation and orientation. The distance over which bed bugs could orient toward a heat source was measured using a 2-choice T-maze assay. Positive thermotaxis was limited to distances <3 cm. Bed bug feeding responses on an artificial feeding system increased with feeder temperature up to 38 and 43°C, and declined precipitously at 48°C. In addition, bed bugs responded to the relative difference between ambient and feeder temperatures. These results highlight the wide range of temperatures that elicit activation, orientation and feeding responses in bed bugs. In contrast, the ability of bed bugs to correctly orient towards a heated target, independently of other cues, is limited to very short distances (<3 cm). Finally, bed bug feeding is shown to be relative to ambient temperature, not an absolute response to feeder blood temperature.

  7. Temperature influences on water permeability and chlorpyrifos uptake in aquatic insects with differing respiratory strategies

    USGS Publications Warehouse

    Buchwalter, D.B.; Jenkins, J.J.; Curtis, L.R.

    2003-01-01

    Aquatic insects have evolved diverse respiratory strategies that range from breathing atmospheric air to breathing dissolved oxygen. These strategies result in vast morphological differences among taxa in terms of exchange epithelial surface areas that are in direct contact with the surrounding water that, in turn, affect physiological processes. This paper examines the effects of acute temperature shifts on water permeability and chlorpyrifos uptake in aquatic insects with different respiratory strategies. While considerable differences existed in water permeability among the species tested, acute temperature shifts raised water influx rates similarly in air-breathing and gill-bearing taxa. This contrasts significantly with temperature-shift effects on chlorpyrifos uptake. Temperature shifts of 4.5??C increased 14C-chlorpyrifos accumulation rates in the gill-bearing mayfly Cinygma sp. and in the air-breathing hemipteran Sigara washingtonensis. However, the temperature-induced increase in 14C-chlorpyrifos uptake after 8 h of exposure was 2.75-fold higher in Cinygma than in Sigara. Uptake of 14C-chlorpyrifos was uniformly higher in Cinygma than in Sigara in all experiments. These findings suggest that organisms with relatively large exchange epithelial surface areas are potentially more vulnerable to both osmoregulatory distress as well as contaminant accumulation. Temperature increases appear more likely to impact organisms that have relatively large exchange epithelial surface areas, both as an individual stressor and in combination with additional stressors such as contaminants.

  8. Viscoelasticity and texture of spreadable cheeses with different fat contents at refrigeration and room temperatures.

    PubMed

    Bayarri, S; Carbonell, I; Costell, E

    2012-12-01

    The effect of the 2 common consumption temperatures, refrigeration temperature (10°C) and room temperature (22°C), on the viscoelasticity, mechanical properties, and perceived texture of commercial cream cheeses was studied. Two samples with different fat contents, regular and low fat, from each of 4 selected commercial brands were analyzed. The selection criteria were based on identification of brands with different percentages of fat content reduction between the regular- and low-fat samples (35, 50, 84, and 98.5%). The fat content of regular-fat samples ranged from 19.8 to 26.0% (wt/wt), and that of low-fat samples ranged from 0.3 to 13.0% (wt/wt). Viscoelasticity was measured in a controlled-stress rheometer using parallel-plate geometry, and the mechanical characteristics of samples were measured using the spreadability test. Differences in the intensity of thickness, creaminess, and roughness between the regular- and low-fat samples of each commercial brand were evaluated at each of the selected temperatures by using the paired comparisons test. At 10°C, all samples showed higher viscoelastic modulus values, firmness, and stickiness, and lower spreadability than when they were measured at 22°C. Differences in viscoelasticity and mechanical properties between each pair of samples of the same brand were greater at 10°C than at 22°C because of the influence not only of fat content but also of fat state. Ingestion temperature did not modify the sensory differences detected between each pair of samples in terms of creaminess and roughness, but it did modify the differences detected in thickness. The joint consideration of sample composition, fat state, and product behavior during oral processing could explain the differences detected in thickness perceived because of measurement temperatures.

  9. Room-temperature terahertz detection based on CVD graphene transistor

    NASA Astrophysics Data System (ADS)

    Yang, Xin-Xin; Sun, Jian-Dong; Qin, Hua; Lv, Li; Su, Li-Na; Yan, Bo; Li, Xin-Xing; Zhang, Zhi-Peng; Fang, Jing-Yue

    2015-04-01

    We report the fabrication and characterization of a single-layer graphene field-effect terahertz detector, which is coupled with dipole-like antennas based on the self-mixing detector model. The graphene is grown by chemical vapor deposition and then transferred onto an SiO2/Si substrate. We demonstrate room-temperature detection at 237 GHz. The detector could offer a voltage responsivity of 0.1 V/W and a noise equivalent power of 207 nW/Hz1/2. Our modeling indicates that the observed photovoltage in the p-type gated channel can be well fit by the self-mixing theory. A different photoresponse other than self-mixing may apply for the n-type gated channel. Project supported by the National Natural Science Foundation of China (Grant Nos. 61271157, 61401456, and 11403084), Jiangsu Provincial Planned Projects for Postdoctoral Research Funds (Grant No. 1301054B), the Fund from Suzhou Industry Technology Bureau (Grant No. ZXG2012024), China Postdoctoral Science Foundation (Grant No. 2014M551678), the Graduate Student Innovation Program for Universities of Jiangsu Province (Grant No. CXLX12_0724), the Fundamental Research Funds for the Central Universities (Grant No. JUDCF 12032), and the Fund from National University of Defense Technology (Grant No. JC13-02-14).

  10. Effects of Temperature on Solute Transport Parameters in Differently-Textured Soils at Saturated Condition

    NASA Astrophysics Data System (ADS)

    Hamamoto, S.; Arihara, M.; Kawamoto, K.; Nishimura, T.; Komatsu, T.; Moldrup, P.

    2014-12-01

    Subsurface warming driven by global warming, urban heat islands, and increasing use of shallow geothermal heating and cooling systems such as the ground source heat pump, potentially causes changes in subsurface mass transport. Therefore, understanding temperature dependency of the solute transport characteristics is essential to accurately assess environmental risks due to increased subsurface temperature. In this study, one-dimensional solute transport experiments were conducted in soil columns under temperature control to investigate effects of temperature on solute transport parameters, such as solute dispersion and diffusion coefficients, hydraulic conductivity, and retardation factor. Toyoura sand, Kaolin clay, and intact loamy soils were used in the experiments. Intact loamy soils were taken during a deep well boring at the Arakawa Lowland in Saitama Prefecture, Japan. In the transport experiments, the core sample with 5-cm diameter and 4-cm height was first isotropically consolidated, whereafter 0.01M KCl solution was injected to the sample from the bottom. The concentrations of K+ and Cl- in the effluents were analyzed by an ion chromatograph to obtain solute breakthrough curves. The solute transport parameters were calculated from the breakthrough curves. The experiments were conducted under different temperature conditions (15, 25, and 40 oC). The retardation factor for the intact loamy soils decreased with increasing temperature, while water permeability increased due to reduced viscosity of water at higher temperature. Opposite, the effect of temperature on solute dispersivity for the intact loamy soils was insignificant. The effects of soil texture on the temperature dependency of the solute transport characteristics will be further investigated from comparison of results from differently-textured samples.

  11. Rheological characterization of novel physically crosslinked terpolymeric hydrogels at different temperatures

    NASA Astrophysics Data System (ADS)

    Malana, Muhammad Aslam; Zohra, Rubab; Khan, Muhammad Saleem

    2012-09-01

    The main objective of this research work is to reveal the detailed and extensive rheological characterization of terpolymeric hydrogel formulations using a variety of monomers having different concentrations of acrylic acid and applying a range of temperatures. The hydrogels with the different concentrations of acrylic acid were prepared in the absence of air using three different monomers, by free radical polymerization, gradually increasing the temperature up to polymerization point, using ethyl alcohol as solvent. Different shear measurements were performed to study rheological properties, temperature dependence, and yield strength of acrylic acid pharmaceutical hydrogels. Various models were applied to analyze the rheological behavior of the gels. The acrylic acid pharmaceutical gels having physical cross links in the gel networks, exhibit remarkable temperature dependence especially with relatively higher concentration of acrylic acid at greater shear rate. Flow curves plotted at various temperatures indicate that these gels exhibit a reasonable pseudoplastic behavior. All these hydrogels require appropriate yield strength to break their network structures. The gel samples exhibit the best fit to the Modified Bingham model, which can explain the overall flow behavior of these topical gels. The rheological analysis indicates that these gels may be used as topical gels for targeted and controlled drug delivery at a specific site.

  12. Temperature-Dependent Differences between Readily Releasable and Reserve Pool Vesicles in Chromaffin Cells

    PubMed Central

    Haynes, Christy L.; Siff, Lauren N.; Wightman, R. Mark

    2007-01-01

    Summary Statistical differences between amperometric traces recorded from chromaffin cells using K+ and Ba2+ secretagogues support the assertion that readily releasable pool (RRP) and reserve pool (RP) vesicles can be probed with pool-specific secretagogues. Release from the RRP was evoked by K+ while release from the RP was evoked by Ba2+. Similar temperature-dependent changes in spike area and half-width for both pools suggest that the content of RRP and RP vesicles is similar and packaged in the same way. Differences between the vesicle pools were revealed in the temperature dependence of spike frequency. While the burst spike frequency of the RRP, which is comprised of pre-docked and primed vesicles, increased 2.8% per °C, the RP spike frequency increased 12% per °C. This difference is attributed to a temperature dependent mobilization of the RP. Furthermore, the RP exhibited more foot events at room temperature than the RRP but this difference was not apparent at 37°C. This trend suggests that RP vesicle membranes have a compromised surface tension compared to RRP vesicles. Collectively, the changes of release characteristics with temperature reveal distinctions between the RRP and the RP. PMID:17467077

  13. SURVIVAL CAPACITY OF Arcobacter butzleri INOCULATED IN POULTRY MEAT AT TWO DIFFERENT REFRIGERATION TEMPERATURES.

    PubMed

    Badilla-Ramírez, Yanán; Fallas-Padilla, Karolina L; Fernández-Jaramillo, Heriberto; Arias-Echandi, María Laura

    2016-01-01

    Arcobacter spp. are emerging enteropathogens and potential zoonotic agents that can be transmitted by food and water, being considered a public health risk. The high isolation rate of these bacteria from poultry products suggests that it may be a major source of human infections. One hallmark for differentiating the genus Arcobacter from Campylobacter includes their growing capacity at low temperatures (15-30 °C) under aerobic conditions. However, little is known about the population density variation of these bacteria at different refrigeration temperatures. The aim of this study was to determine the survival behavior of two different Arcobacter butzleri concentrations (10(4) CFU/mL and 10(7) CFU/mL) inoculated on chicken legs and held at two different refrigeration temperatures (4 and 10 °C) throughout storage time. Results have shown that A. butzleri had growing capacity both at 4 and 10 °C. No statistical difference between the survival trends was found for both bacterial concentrations and temperatures tested. This study shows that A. butzleri is a robust species with regard to storage temperature, and represents a potential health risk for poultry meat consumers.

  14. Finite difference modelling of the temperature rise in non-linear medical ultrasound fields.

    PubMed

    Divall, S A; Humphrey, V F

    2000-03-01

    Non-linear propagation of ultrasound can lead to increased heat generation in medical diagnostic imaging due to the preferential absorption of harmonics of the original frequency. A numerical model has been developed and tested that is capable of predicting the temperature rise due to a high amplitude ultrasound field. The acoustic field is modelled using a numerical solution to the Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation, known as the Bergen Code, which is implemented in cylindrical symmetric form. A finite difference representation of the thermal equations is used to calculate the resulting temperature rises. The model allows for the inclusion of a number of layers of tissue with different acoustic and thermal properties and accounts for the effects of non-linear propagation, direct heating by the transducer, thermal diffusion and perfusion in different tissues. The effect of temperature-dependent skin perfusion and variation in background temperature between the skin and deeper layers of the body are included. The model has been tested against analytic solutions for simple configurations and then used to estimate temperature rises in realistic obstetric situations. A pulsed 3 MHz transducer operating with an average acoustic power of 200 mW leads to a maximum steady state temperature rise inside the foetus of 1.25 degrees C compared with a 0.6 degree C rise for the same transmitted power under linear propagation conditions. The largest temperature rise occurs at the skin surface, with the temperature rise at the foetus limited to less than 2 degrees C for the range of conditions considered.

  15. Temperature and functional traits influence differences in nitrogen uptake capacity between native and invasive grasses.

    PubMed

    Leffler, A Joshua; James, Jeremy J; Monaco, Thomas A

    2013-01-01

    Performance differences between native and exotic invasive plants are often considered static, but invasive grasses may achieve growth advantages in western North America shrublands and steppe under only optimal growing conditions. We examine differences in N uptake and several morphological variables that influence uptake at temperatures between 5 and 25 °C. We contrast two native perennial grasses in western North America: Elymus elymoides and Pseudoroegneria spicata; two invasive annual grasses: Bromus tectorum and Taeniatherum caput-medusae; and one highly selected non-native perennial grass: Agropyron cristatum. The influence of temperature on N uptake is poorly characterized, yet these invasive annual grasses are known to germinate in warm soils in the autumn, and both experience cool soils during the short growing season following snowmelt in the spring. To further explore the influence of temperature on the correlation between morphological variables and N uptake, our data are applied to a previously published path model and one proposed here. Differences in N uptake between native and invasive grasses were small at the lowest temperature, but were large at the highest temperature. At lower temperatures, uptake of N by annuals and perennials was correlated with leaf N and mass. At higher temperatures, uptake by annuals was correlated only with these leaf traits, but uptake by perennials was correlated with these leaf traits as well as root N and mass. Consequently, our results imply that annual grasses face fewer morphological constraints on N uptake than perennial grasses, and annual grasses may gain further advantage in warmer temperature conditions or during more frequent warm periods.

  16. Genetically determined differences in ethanol sensitivity influenced by body temperature during intoxication

    SciTech Connect

    Alkana, R.L.; Finn, D.A.; Bejanian, M.; Crabbe, J.C.

    1988-01-01

    The present study investigated the importance of body temperature during intoxication in mediating differences between five inbred strains of mice (C57BL/6J; BALB/cJ; DBA/2J; A/HeJ; 129/J) in their acute sensitivity to the hypnotic effects of ethanol. Mice exposed to 22/degrees/C after ethanol injection became hypothermic and exhibited statistically significant differences between strains in rectal temperatures at the return of the righting reflex (RORR), duration of loss of the righting reflex (LORR), and blood and brain ethanol concentrations at RORR. Exposure to 34/degrees/C after injection offset ethanol-hypothermia and markedly reduced strain-related differences in rectal temperatures and blood and brain ethanol concentrations at RORR. Brain ethanol concentrations at RORR were significantly lower in C57, BALB, DBA and A/He mice exposed to 34/degrees/C compared to mice exposed to 22/degrees/C during intoxication suggesting that offsetting hypothermia increased ethanol sensitivity in these strains. Taken with previous in vitro studies, these results suggest that genetically determined differences in acute sensitivity to the behavioral effects of ethanol reflect differences in body temperature during intoxication as well as differences in sensitivity to the initial actions of ethanol at the cellular level.

  17. Performance of Hg1‑xCdxTe infrared focal plane array at elevated temperature

    NASA Astrophysics Data System (ADS)

    Singh, Anand; Pal, Ravinder

    2017-04-01

    The simulated optical and electrical performance of the infrared HgCdTe focal plane array (FPA) for elevated operation temperature is reported. The depleted absorber layer is explored for equilibrium mode of operation up to 160 K. A resonant cavity is created to improve photon-matter interaction and hence, reduces the required absorption volume. The volume of the active region of HgCdTe detector is reduced by 70% in this manner. Dark current density is decreased without compromising the quantum efficiency. The effect of the reduced band filling effect leading to higher absorption coefficient and more efficient utilization of incident flux is employed. High quantum efficiency is achieved in a thin compositionally graded n+/ν/π/p HgCdTe photo-diode. This architecture helps to minimize the requirement of charge handling capacity in the CMOS read-out integrated circuit (ROIC) as the operation temperature is increased. Quantum efficiency ∼30% or above is shown to be sufficient for Noise Equivalent Temperature Difference (NETD) less than 20 mK with the reported design.

  18. Thermal fluctuations of haemoglobin from different species: adaptation to temperature via conformational dynamics.

    PubMed

    Stadler, A M; Garvey, C J; Bocahut, A; Sacquin-Mora, S; Digel, I; Schneider, G J; Natali, F; Artmann, G M; Zaccai, G

    2012-11-07

    Thermodynamic stability, configurational motions and internal forces of haemoglobin (Hb) of three endotherms (platypus, Ornithorhynchus anatinus; domestic chicken, Gallus gallus domesticus and human, Homo sapiens) and an ectotherm (salt water crocodile, Crocodylus porosus) were investigated using circular dichroism, incoherent elastic neutron scattering and coarse-grained Brownian dynamics simulations. The experimental results from Hb solutions revealed a direct correlation between protein resilience, melting temperature and average body temperature of the different species on the 0.1 ns time scale. Molecular forces appeared to be adapted to permit conformational fluctuations with a root mean square displacement close to 1.2 Å at the corresponding average body temperature of the endotherms. Strong forces within crocodile Hb maintain the amplitudes of motion within a narrow limit over the entire temperature range in which the animal lives. In fully hydrated powder samples of human and chicken, Hb mean square displacements and effective force constants on the 1 ns time scale showed no differences over the whole temperature range from 10 to 300 K, in contrast to the solution case. A complementary result of the study, therefore, is that one hydration layer is not sufficient to activate all conformational fluctuations of Hb in the pico- to nanosecond time scale which might be relevant for biological function. Coarse-grained Brownian dynamics simulations permitted to explore residue-specific effects. They indicated that temperature sensing of human and chicken Hb occurs mainly at residues lining internal cavities in the β-subunits.

  19. Demographic comparison and population projection of Rhynchophorus ferrugineus (Coleoptera: Curculionidae) reared on sugarcane at different temperatures

    PubMed Central

    Peng, Lu; Miao, Yunxin; Hou, Youming

    2016-01-01

    Understanding how temperature affects fitness is important for conservation and pest management, especially in the era of global climate change. Rhynchophorus ferrugineus (Oliver) (Coleoptera: Curculionidae) is a worldwide pest of many economically important crops. Although much is known about this pest’s life cycle, its adaptability to different temperatures is not fully understood. Here, we used age- and stage-specific life tables to investigate the effects of temperature on fitness-related traits and demographic parameters of R. ferrugineus under eight constant temperature regimens in the laboratory. The growth potential of these populations was also evaluated. The greatest longevity for males and females was 158.0 d at 24 °C and 144.5 d at 21 °C, respectively, but mean total fecundity was the highest at 27 °C. The intrinsic rate of increase (r), finite rate of increase (λ), and net reproductive rate (R0) increased initially at low temperatures and then decreased. All metrics reached a maximum at 27 °C and a minimum at 36 °C. Mean generation times (T ) decreased across the temperature range with a minimum at 36 °C. Our results indicate that the optimum temperature for growth of R. ferrugineus was approximately 27 °C. Our work will be of value for developing strategies for control management of this pest species. PMID:27545594

  20. Coffee roasting and aroma formation: application of different time-temperature conditions.

    PubMed

    Baggenstoss, Juerg; Poisson, Luigi; Kaegi, Ruth; Perren, Rainer; Escher, Felix

    2008-07-23

    The impact of time-temperature combinations of roasting processes on the kinetics of aroma formation in coffee was investigated. The development of 16 aroma compounds and the physical properties of coffee beans was followed in a commercial horizontal drum roasting process and in laboratory scale fluidizing-bed roasting processes at high temperature-short time and low temperature-long time conditions. All trials were run to an equal roast end point as defined by the lightness of coffee beans. In addition, the effect of excessive roasting on aroma composition was studied. Compared to low temperature-long time roasting, high temperature-short time roasting resulted in considerable differences in the physical properties and kinetics of aroma formation. Excessive roasting generally led to decreasing or stable amounts of volatile substances, except for hexanal, pyridine, and dimethyl trisulfide, whose concentrations continued to increase during over-roasting. When the drum roaster and the fluidizing bed roaster were operated in the so-called temperature profile mode, that is, along the identical development of coffee bean temperature over roasting time, the kinetics of aroma generation were similar in both processes.

  1. Temperature-difference-driven mass transfer through the vapor from a cold to a warm liquid.

    PubMed

    Struchtrup, Henning; Kjelstrup, Signe; Bedeaux, Dick

    2012-06-01

    Irreversible thermodynamics provides interface conditions that yield temperature and chemical potential jumps at phase boundaries. The interfacial jumps allow unexpected transport phenomena, such as the inverted temperature profile [Pao, Phys. Fluids 14, 306 (1971)] and mass transfer from a cold to a warm liquid driven by a temperature difference across the vapor phase [Mills and Phillips, Chem. Phys. Lett. 372, 615 (2002)]. Careful evaluation of the thermodynamic laws has shown [Bedeaux et al., Physica A 169, 263 (1990)] that the inverted temperature profile is observed for processes with a high heat of vaporization. In this paper, we show that cold to warm mass transfer through the vapor from a cold to a warm liquid is only possible when the heat of evaporation is sufficiently small. A necessary criterium for the size of the mass transfer coefficient is given.

  2. Surface acoustic wave velocity of gold films deposited on silicon substrates at different temperatures

    SciTech Connect

    Salas, E.; Jimenez Rioboo, R. J.; Prieto, C.; Every, A. G.

    2011-07-15

    Au thin films have been deposited by DC magnetron sputtering on Si (001) substrates at different substrate temperatures, ranging from 200 K to 450 K. With increasing temperature, the expected crystallinity and morphology of the Au thin film are clearly improved, as shown by x ray diffraction, atomic force microscopy and scanning electron microscopy experiments. Parallel to this, the surface acoustic wave propagation velocity shows a clear enhancement toward the ideal values obtained from numerical simulations of a Au thin film on Si (001) substrate. Moreover, a very thin and slightly rough interlayer between the Si (001) substrate and the Au thin film is developed for temperatures above 350 K. The composition and nature of this interlayer is not known. This interlayer may be responsible for the steep change in the structural and elastic properties of the Au thin films at the higher temperatures and possibly also for an improvement of the adhesion properties of the Au on the Si (001) substrate.

  3. Self-diffusion of lignite/water under different temperatures and pressure: A molecular dynamics study

    NASA Astrophysics Data System (ADS)

    Liu, Xinjian; Jin, Yu; Huang, Congliang; He, Jingfeng; Rao, Zhonghao; Zhao, Yuemin

    2016-01-01

    Temperature and pressure have direct and remarkable implications for drying and dewatering effect of low rank coals such as lignite. To understand the microenergy change mechanism of lignite, the molecular dynamics simulation method was performed to study the self-diffusion of lignite/water under different temperatures and pressure. The results showed that high temperature and high pressure can promote the diffusion of lignite/water system, which facilitates the drying and dewatering of lignite. The volume and density of lignite/water system will increase and decrease with temperature increasing, respectively. Though the pressure within simulation range can make lignite density increase, the increasing pressure showed a weak impact on variation of density.

  4. Effects of different sitting positions on skin temperature of the lower extremity.

    PubMed

    Namkoong, Seung; Shim, JeMyung; Kim, SungJoong; Shim, JungMyo

    2015-08-01

    [Purpose] The purpose of this study was to identify the effect of different sitting positions on the skin temperature of the lower extremity. [Subjects] The subjects of this study were 23 healthy university students (8 males, 15 females). [Methods] Normal sitting (NS), upper leg cross (ULC) and ankle on knee (AOK) positions were conducted to measure the changes in skin temperature using digital infrared thermographic imaging (DITI). [Results] ULC upper ankle, NS upper shin, ULC upper shin and NS lower shin showed significant declines in temperature with time. [Conclusion] These finding suggest that the ULC and NS sitting positions cause decline of blood flow volume to the lower extremity resulting in decrease of temperature of the lower extremity. Especially, sitting with the legs crossed interferes with the circulation of blood flowing volume much more than just sitting in a chair.

  5. The forms of alkalis in the biochar produced from crop residues at different temperatures.

    PubMed

    Yuan, Jin-Hua; Xu, Ren-Kou; Zhang, Hong

    2011-02-01

    The forms of alkalis of the biochars produced from the straws of canola, corn, soybean and peanut at different temperatures (300, 500 and 700°C) were studied by means of oxygen-limited pyrolysis. The alkalinity and pH of the biochars increased with increased pyrolysis temperature. The X-ray diffraction spectra and the content of carbonates of the biochars suggested that carbonates were the major alkaline components in the biochars generated at the high temperature; they were also responsible for the strong buffer plateau-regions on the acid-base titration curves at 500 and 700°C. The data of FTIR-PAS and zeta potentials indicated that the functional groups such as -COO(-) (-COOH) and -O(-) (-OH) contained by the biochars contributed greatly to the alkalinity of the biochar samples tested, especially for those generated at the lower temperature. These functional groups were also responsible for the negative charges of the biochars.

  6. Locomotor activity and body temperature in selected mouse lines differing greatly in feed intake.

    PubMed

    Sojka, P A; Griess, R S; Nielsen, M K

    2013-08-01

    Locomotor activity, body temperature, feed intake, and BW were measured on 382 mature male mice sampled from lines previously selected (25 generations) for either high (MH) or low (ML) heat loss and an unselected control (MC). Animals were from all 3 independent replicates of the 3 lines and across 4 generations (68 through 71). Locomotor activity and body temperatures were obtained using implanted transmitters with data collection over 4 d following a 3-d postsurgery recovery period. Data were collected every minute and then averaged into 30-min periods, thus providing 192 data points for each mouse. Least-squares means for feed intake adjusted for BW (Feed/BW, feed·BW(-1)·d(-1), g/g) were 0.1586, 0.1234, and 0.1125 (±0.0022) for MH, MC, and ML, respectively, with line being a highly significant source of variation (P < 0.0003). Line effects for locomotor activity counts, transformed to the 0.25 power for analysis, were significantly different, with MH mice being 2.1 times more active than ML mice (P < 0.003); MC mice were intermediate. Differences in body temperature were significant for both line (P < 0.03) and day effects (P < 0.001), with a 0.32°C difference between the MH and ML lines. Fourier series analysis used the combined significant periodicities of 24, 18, 12, 9, 6, and 3 h to describe circadian cycles for activity and body temperature. All 3 lines expressed daily peaks in body temperature and locomotor activity ∼3 h into darkness and ∼2 h after lights were turned on. There was a stronger relationship between locomotor activity and Feed/BW (P < 0.0001) than between body temperature and Feed/BW (P < 0.01); differences between lines in locomotor activity and body temperature explained 17% and 3%, respectively, of differences between lines in Feed/BW. Thus, line differences in locomotor activity contribute to line differences in maintenance, but approximately 80% of the differences between the MH and ML selection lines in Feed/BW remains

  7. Behavior, metabolism and swimming physiology in juvenile Spinibarbus sinensis exposed to PFOS under different temperatures.

    PubMed

    Xia, Ji-Gang; Nie, Li-Juan; Mi, Xia-Mei; Wang, Wei-Zhen; Ma, Yi-Jie; Cao, Zhen-Dong; Fu, Shi-Jian

    2015-10-01

    The harmful effects of perfluorooctane sulfonate (PFOS) are of growing international concern. This paper aimed to gain an integrated understanding of fitness-related ecological end points, such as behavior, metabolism and swimming physiology, in juvenile Spinibarbus sinensis in response to PFOS toxicity at different temperatures. The fish were exposed to a range of PFOS concentrations (0, 0.32, 0.8, 2 and 5 mg/L) at different temperatures (18 and 28 °C) for 30 days. The effects on fish behavior, metabolic characteristics and aerobic swimming performance caused by PFOS at different temperatures were investigated. Our results showed that both PFOS and temperature had important influences on spontaneous swimming behavior, social interactions, routine metabolic rate (RMR), net energetic cost of transport (COTnet) and critical swimming speed (U crit) in fish. The lowest observed effect concentration for both U crit and RMR was 5 and 0.8 mg/L at 18 and 28 °C, respectively. We found that PFOS affected various behavioral and social end points and also appeared to affect metabolic rates and reduced U crit, likely as a result of increased COTnet, and that many of these effects also changed with respect to temperature. Our results further the understanding of the metabolic and behavioral toxicity of PFOS to aquatic organisms.

  8. Metabolic flux and nodes control analysis of brewer's yeasts under different fermentation temperature during beer brewing.

    PubMed

    Yu, Zhimin; Zhao, Haifeng; Zhao, Mouming; Lei, Hongjie; Li, Huiping

    2012-12-01

    The aim of this work was to further investigate the glycolysis performance of lager and ale brewer's yeasts under different fermentation temperature using a combined analysis of metabolic flux, glycolytic enzyme activities, and flux control. The results indicated that the fluxes through glycolytic pathway decreased with the change of the fermentation temperature from 15 °C to 10 °C, which resulted in the prolonged fermentation times. The maximum activities (V (max)) of hexokinase (HK), phosphofructokinase (PFK), and pyruvate kinase (PK) at key nodes of glycolytic pathway decreased with decreasing fermentation temperature, which was estimated to have different control extent (22-84 %) on the glycolytic fluxes in exponential or flocculent phase. Moreover, the decrease of V (max) of PFK or PK displayed the crucial role in down-regulation of flux in flocculent phase. In addition, the metabolic state of ale strain was more sensitive to the variation of temperature than that of lager strain. The results of the metabolic flux and nodes control analysis in brewer's yeasts under different fermentation temperature may provide an alternative approach to regulate glycolytic flux by changing V (max) and improve the production efficiency and beer quality.

  9. Temperature rise during polymerization of different cavity liners and composite resins

    PubMed Central

    Karatas, Ozcan; Turel, Verda; Bayindir, Yusuf Ziya

    2015-01-01

    Objective: The purpose of this study was to evaluate the thermal insulating properties of different light curing cavity liners and composite resins during light emitting diode (LED) curing. Materials and Methods: Sixty-four dentin discs, 1 mm thick and 8 mm in diameter, were prepared. Specimens were divided into four groups. Calcium hydroxide (Ca[OH]2), resin-modified glass ionomer cement, flowable composite and adhesive systems were applied to dentin discs according to the manufacturers’ instructions. The rise in temperature during polymerization with a LED curing unit (LCU) was measured using a K-type thermocouple connected to a data logger. Subsequently, all specimens were randomly divided into one of two groups. A silorane-based composite resin and a methacrylate-based composite resin were applied to the specimens. Temperature rise during polymerization of composite resins with LCU were then measured again. Data were analyzed using one-way ANOVA and post hoc Tukey analyses. Results: There were significant differences in temperature rise among the liners, adhesives, and composite resins (P < 0.05). Silorane-based composite resin exhibited significantly greater temperature rises than methacrylate-based resin (P < 0.05). The smallest temperature rises were observed in Ca(OH)2 specimens. Conclusion: Thermal insulating properties of different restorative materials are important factors in pulp health. Bonding agents alone are not sufficient to protect pulp from thermal stimuli throughout curing. PMID:26751112

  10. Analysis of temperature difference on the total of energy expenditure during static bicycle exercise

    NASA Astrophysics Data System (ADS)

    Sugiono

    2016-04-01

    How to manage energy expenditure for cyclist is very crucial part to achieve a good performance. As the tropical situation, the differences of temperature level might be contributed in energy expenditure and durability. The aim of the paper is to estimate and to analysis the configuration of energy expenditure for static cycling activity based on heart rate value in room with air conditioning (AC)/no AC treatment. The research is started with study literatures of climate factors, temperature impact on human body, and definition of energy expenditure. The next step is design the experiment for 5 participants in 2 difference models for 26.80C - 74% relative humidity (room no AC) and 23,80C - 54.8% relative humidity (room with AC). The participants’ heart rate and blood pressure are measured in rest condition and in cycling condition to know the impact of difference temperature in energy expenditure profile. According to the experiment results, the reducing of the temperature has significantly impact on the decreasing of energy expenditure at average 0.3 Kcal/minute for all 5 performers. Finally, the research shows that climate condition (temperature and relative humidity) are very important factors to manage and to reach a higher performance of cycling sport.

  11. Hot in Baltimore: linking urban form to fine-scale temperature differences

    NASA Astrophysics Data System (ADS)

    Scott, A.; Waugh, D.; Zaitchik, B. F.; Guikema, S.

    2015-12-01

    Better understanding how urban morphology creates microclimates can help policymakers and planners mitigate the effects of heatwaves and other negative urban heat island effects. In Baltimore, where the observed downtown-rural temperature difference (as measured by NOAA stations) can reach 5°C, low-income neighborhoods are almost entirely covered by impervious surfaces like concrete but lack trees and parks. Their urban-rural temperature difference is then expected to exceed the reported one. However, that difference is not well quantified because these areas lack weather station coverage. Additionally, high resolution satellite imagery shows only land surface temperatures (inadequate for policy and health interventions) and may miss severe heat events. To remedy this, a low-cost monitoring network was installed in East Baltimore over summer 2015 aiming to characterize spatial and temporal variability and examine how heat excess varies during heat events. Results confirm that E. Baltimore exceeds downtown temperatures and show that a dense network of low cost sensors can help attribute temperature anomalies to local features such as land cover, building density and tree canopy.

  12. Antioxidant activity and free radical-scavenging capacity of Gynura divaricata leaf extracts at different temperatures

    PubMed Central

    Wan, Chunpeng; Yu, Yanying; Zhou, Shouran; Liu, Wei; Tian, Shuge; Cao, Shuwen

    2011-01-01

    Background: Extraction temperature influences the total phenolic content (TPC), total flavonoid content (TFC) of medicinal plant extracts to a great extend. TPC and TFC are the principle activity constituents present in the plant. The effects of extraction temperature on TPC, TFC and free radical-scavenging capacity of Gynura divaricata leaf extracts are worth to study. Materials and Methods: Folin–Ciocalteu and aluminum chloride colorimetric assay were used to determine the TPC and TFC of Gynura divaricata leaf extracts at different temperatures. The antioxidant and free radical-scavenging activity were measured by 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2-azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid (ABTS) and phosphomolybdenum methods. Results: TPC and TFC were significantly elevated with increasing extraction temperature (from 40°C to 100°C). However, TPC and TFC were not significantly different (P > 0.05) at the extraction temperatures 90°C and 100°C. Also, the extracts obtained at a higher temperature exhibited a significant free radical-scavenging activity compared with extraction at lower temperatures (P < 0.05). The TPCs (13.95-36.68 mg gallic acid equivalent/g dry material) were highly correlated with DPPH (R2 = 0.9229), ABTS (R2 = 0.9951) free radical-scavenging capacity, and total antioxidant activity (R2 = 0.9872) evaluated by phosphomolybdenum method. Conclusion: The TPC and TFC of G. divaricata leaf was significantly influenced by the extraction temperatures, which were the main antioxidant constituents present in the G. divaricata plant. PMID:21472078

  13. [The Influence of Different Ionic Concentration in Cell Physiological Solution on Temperature Measurement by Near Infrared].

    PubMed

    Zheng, Yu; Chen, Xiong; Zhou, Mei; Wang, Meng-jun; Wang, Jin-hai; Li, Gang; Cui, Jun

    2015-10-01

    It is important to real-timely monitor and control the temperature of cell physiological solution in patch clamp experiments, which can eliminate the uncertainty due to temperature and improve the measurement accuracy. This paper studies the influence of different ions at different concentrations in the physiological solution on precision of a temperature model by using near infrared spectroscopy and chemometrics method. Firstly, we prepared twelve sample solutions respectively with the solutes of CaCl2, KCl and NaCl at four kinds of concentrations, and collected the spectra of different solutions at the setting temperature range 20-40 degrees C, the range of the spectra is 9 615-5 714 cm(-1). Then we divided the spectra of each solution at different temperatures into two parts (a training set and a prediction set) by three methods. Interval partial least squares method was used to select an effective wavelength range and develop calibration models between the spectra in the selected range and temperature velues. The experimental results show that RMSEP of CaCl2 solution with 0.25 g x mL(-1) is maximum, the result of the three tests are 0.386 3, 0.303 7 and 0.337 2 degrees C, RMSEP of NaCl with 0.005 g x mL(-1) solution is minimum, the result of the three tests are 0.220 8, 0.155 3 and 0.145 2 degrees C. The experimental results indicate that Ca2+ has the greatest influence on the accuracy of the temperature model of the cell physiological solution, then K+, and Na+ has the least influence. And with the ionic concentration increasing, the model accuracy decreases. Therefore; when we build the temperature model of cell physiological solution, it is necessary to change the proportion of the three kinds of main ions in cell physiological solution reasonably in order to correct the effects of different ionic concentrations in physiological solution and improve the accuracy of temperature measurements by near infrared spectroscopy.

  14. Systematic Pressure and Temperature Differences between Vaisala RS80 and RS92 Radiosonde-Systems

    NASA Astrophysics Data System (ADS)

    Steinbrecht, W.; Claude, H.; Schönenborn, F.

    2008-12-01

    National meteorological centers are replacing the widely used Vaisala RS80 radiosonde with the newer RS90 or RS92. Such change-overs often introduce erroneous steps into long-term atmospheric temperature records. We show that twin-flight campaigns with RS80 and RS92 sondes on the same balloon, and the transition from RS80 to RS92 in operational radio-soundings over Germany, consistently indicate higher temperature readings from RS92 sondes in the stratosphere. In our presentation we summarize these main differences between RS80 and RS92. Significant differences are found in the stratosphere, above the 100~hPa level. The accuracy of our temperature results is of the order of 0.1 to 0.5~K, and at this level we were not able to find significant differences in the troposphere, although there are indications for slightly higher daytime temperatures from RS92 sondes. During day-time and near 50~hPa, RS92s report +0.3 ± 0.2~K higher temperature than RS80s, increasing to +0.7 ± 0.4~K near 10~hPa (2σ uncertainties). At night, the difference is smaller, +0.1 ± 0.1~K near 50~hPa to +0.35 ± 0.2~K near 10~hPa. The mean day-to-night difference (12-00~UT) is also larger for RS92s, by 0.1± 0.06~K near 70~hPa, and by 0.76± 0.16~K near 10~hPa. The main contribution to this stratospheric day-time difference comes from an over-correction of the radiation error in the Vaisala RS80 data processing. The night-time difference at stratospheric levels (and part of the day-time difference) is due to a low bias of the RS80 pressure measurement, typically by -0.4~hPa near 10~hPa. This shifts temperature readings to lower pressure/ higher altitude. For stratospheric levels, it results in lower temperatures from RS80 sondes (due to the vertical temperature increase). Generally, RS92s give better temperature repeatabiliy, ±0.25~K (2σ) near 50~hPa, and much more precise pressure, ±0.2~hPa near 50~hPa, compared to RS80 systems, ±0.5~K, or ±1.5~hPa. Geopotential heights from RS92s are

  15. Compositional and mechanical properties of peanuts roasted to equivalent colors using different time/temperature combinations.

    PubMed

    McDaniel, Kristin A; White, Brittany L; Dean, Lisa L; Sanders, Timothy H; Davis, Jack P

    2012-12-01

    Peanuts in North America and Europe are primarily consumed after dry roasting. Standard industry practice is to roast peanuts to a specific surface color (Hunter L-value) for a given application; however, equivalent surface colors can be attained using different roast temperature/time combinations, which could affect product quality. To investigate this potential, runner peanuts from a single lot were systematically roasted using 5 roast temperatures (147, 157, 167, 177, and 187 °C) and to Hunter L-values of 53 ± 1, 48.5 ± 1, and 43 ± 1, corresponding to light, medium, and dark roasts, respectively. Moisture contents (MC) ranged from 0.41% to 1.70% after roasting. At equivalent roast temperatures, MC decreased as peanuts became darker; however, for a given color, MC decreased with decreasing roast temperature due to longer roast times required for specified color formation. Initial total tocopherol contents of expressed oils ranged from 164 to 559 μg/g oil. Peanuts roasted at lower temperatures and darker colors had higher tocopherol contents. Glucose content was roast color and temperature dependent, while fructose was only temperature dependent. Soluble protein was lower at darker roast colors, and when averaged across temperatures, was highest when samples were roasted at 187 °C. Lysine content decreased with increasing roast color but was not dependent on temperature. MC strongly correlated with several components including tocopherols (R(2) = 0.67), soluble protein (R(2) = 0.80), and peak force upon compression (R(2) = 0.64). The variation in characteristics related to roast conditions is sufficient to suggest influences on final product shelf life and consumer acceptability.

  16. Influence of Different Temperature Sensors on Measuring Energy Efficiency and Heating-Up Time of Hobs

    NASA Astrophysics Data System (ADS)

    Beges, G.; Drnovsek, J.; Ogorevc, J.; Bojkovski, J.

    2015-03-01

    Measuring performance, mainly temperature dependence, for electric cooking ranges, hobs, ovens, and grills for household use is essential for producers as low power consumption of appliances represents a powerful selling point and also in terms of ecodesign requirements. It is also important from a consumer perspective, as these appliances are responsible for the significant share of households' electricity bills. The aim of the paper was to highlight and clearly define possible ambiguities and weaknesses of standardized procedures for measuring hob performance. Differences between measurement/test results of testing laboratories are possible due to lack of detailed information in the standard, and it is difficult to obtain technical accessories required in the standard. An energy consumption comparison of three different hobs is presented (standard iron electrical hob, radiant-glass ceramic, and induction hob). Various temperature sensors (different types of thermocouples and a platinum resistance thermometer) and technical accessories (e.g., different cookware) were used to research differences or influences on final result of hobs' energy efficiency. Results show that temperature measurements with different sensors have an influence on the time difference in critical points for determination of hob energy efficiency.

  17. Influence of the mode geometry on the strain and temperature sensitivity of different fibers

    NASA Astrophysics Data System (ADS)

    Murawski, M.; Holdynski, Z.; Szymanski, M.; Tenderenda, T.; Ostrowski, L.; Łukowski, A.; Krisch, H.; Napierała, M.; Jaroszewicz, L. R.; Nasilowski, T.

    2013-05-01

    Sensitivity of optical fibers to the temperature, longitudinal strain or pressure, is a very important feature in many applications, such as sensors or telecommunication. The most common way to modify (depending on application - either mitigate or strengthen,) this sensitivity is changing the fiber material properties by appropriate glass doping or by employing appropriate microstructure in the fiber. In some cases the precise adjustment of a doping level and sophisticated design of air-holes arrangement is needed to obtain required features of the fiber. In this paper, for the first time, to the best of our knowledge, we report the investigation of the mode area and geometry influence on the fiber temperature and mechanical sensitivities. To do so, we engaged a dedicated all-fiber interferometer which enables the measurement of the temperature and longitudinal strain sensitivities of different fiber types, including conventional and microstructured fibers with different core diameters.

  18. Effects of different temperatures and duration on germination of caper (Capparis ovata) seeds.

    PubMed

    Basbag, Mehmet; Toncer, Ozlem; Basbag, Sema

    2009-07-01

    Caperseed has poor germination because of the seed coat dormancy Germination of caperseeds are complex traits affected by a wide range of intemal and environmental influences. The effects of temperature preconditioning and period on germination of Capparis ovata were examined. Experiments were conducted in order to investigate germination behaviour of caperseeds subjected to different temperature and duration. The experiment revealed that the different temperature treatments were effective on mean germination percentage. The highest mean germination were obtained at 0 degree C 29.52% and 10 degrees C with 27.17% and the lowest mean germination were obtained at control seeds with 8.39%. Dry heat treatments effected germination rate, but it was not enough for removing germination obstacle of caper seed completely.

  19. Difference method for analysing infrared images in pigs with elevated body temperatures.

    PubMed

    Siewert, Carsten; Dänicke, Sven; Kersten, Susanne; Brosig, Bianca; Rohweder, Dirk; Beyerbach, Martin; Seifert, Hermann

    2014-03-01

    Infrared imaging proves to be a quick and simple method for measuring temperature distribution on the pig's head. The study showed that infrared imaging and analysis with a difference ROI (region of interest) method may be used for early detection of elevated body temperature in pigs (> 39.5°C). A high specificity of approx. 85% and a high sensitivity of 86% existed. The only prerequisite is that there are at least 2 anatomical regions which can be recognised as reproducible in the IR image. Noise suppression is guaranteed by averaging the temperature value within both of these ROI. The subsequent difference imaging extensively reduces the off-set error which varies in every thermal IR-image.

  20. Vertical Magnetic Levitation Force Measurement on Single Crystal YBaCuO Bulk at Different Temperatures

    NASA Astrophysics Data System (ADS)

    Celik, Sukru; Guner, Sait Baris; Ozturk, Kemal; Ozturk, Ozgur

    Magnetic levitation force measurements of HTS samples are performed with the use of liquid nitrogen. It is both convenient and cheap. However, the temperature of the sample cannot be changed (77 K) and there is problem of frost. So, it is necessary to build another type of system to measure the levitation force high Tc superconductor at different temperatures. In this study, we fabricated YBaCuO superconducting by top-seeding-melting-growth (TSMG) technique and measured vertical forces of them at FC (Field Cooling) and ZFC (Zero Field Cooling) regimes by using our new designed magnetic levitation force measurement system. It was used to investigate the three-dimensional levitation force and lateral force in the levitation system consisting of a cylindrical magnet and a permanent cylindrical superconductor at different temperatures (37, 47, 57, 67 and 77 K).

  1. Effects of wearing two different types of clothing on body temperatures during and after exercise

    NASA Astrophysics Data System (ADS)

    Jeong, Woon Seon; Tokura, Hiromi

    1989-06-01

    The experiment was conducted to investigate the human thermoregulatory responses during rest, exercise and recovery at T a 20°C and 60% R.H. under the conditions of wearing two different types of clothing. Six healthy men wore two types of clothing: one covering the whole body area except the head (Type A, weight 1656 g), and the other covering only the trunk, upper arms and thighs (Type B, weight 996 g). The level of rectal temperature was kept significantly higher in Type B than in Type A during rest and recovery. The increased and decreased rates of rectal temperature during exercise and recovery were significantly greater in Type A than in Type B, respectively. These findings are discussed from the viewpoint of the differences of skin temperatures of the extremities between Type A and Type B.

  2. Eccentric variation of corneal sensitivity to pneumatic stimulation at different temperatures and with CO2.

    PubMed

    Situ, P; Simpson, T L; Fonn, D

    2007-09-01

    The purpose was to measure corneal sensitivity at multiple corneal positions using pneumatic stimuli, at room temperature and at ocular surface temperature (with and without CO(2) added), in 15 healthy participants. Sensitivity of central, mid-peripheral, and peripheral cornea was measured using a computer-controlled modified Belmonte esthesiometer to deliver pneumatic cool (air at 20 degrees C), mechanical (air at 50 degrees C), and chemical stimuli (air at 50 degrees C with CO(2) added). The ascending method of limits and method of constant stimuli were adopted to determine the threshold to these stimuli at each location. Sensitivity across the cornea using pneumatic stimuli at different temperatures and chemical stimuli varied only slightly. These patterns of variation are different to what has been previously reported using Cochet-Bonnet esthesiometry.

  3. Frequency moments and elastic moduli of liquid rubidium at different temperatures

    NASA Astrophysics Data System (ADS)

    Patel, A. B.; Bhatt, N. K.; Thakore, B. Y.; Jani, A. R.

    2013-06-01

    To shed light on structural and vibrational dynamics of liquid rubidium (Rb) at different temperatures; a treatment of pseudopotential theory has been performed. The temperature dependence of structure factor and pair correlation functions has been determined using Percus-Yevick approximation consistent to the model potential used. In the present study, a modified empty core potential is employed to explain an electron-ion interaction. It consists of the full electron-ion interaction and a delta function which represents the orthogonalisation effect due to the s-core states in such sp-bonded metals. The temperature dependence of pair potential is achieved by using the damping factor exp(-αkBTr/2kF) in the pair potential. Expressions for phonon dispersions are derived using different frequency moments. Results for longitudinal phonon frequencies and various elastic moduli are obtained.

  4. The study of the formation of monolayers of quantum dots at different temperatures

    NASA Astrophysics Data System (ADS)

    Gorbachev, Ilya A.; Goryacheva, Irina Y.; Brezesinski, Gerald; Gluhovskoy, Evgeny G.

    2016-04-01

    The process of formation of Langmuir monolayers of quantum dots at the different subphase temperatures was studied by means of compression isotherm, Brewster angle microscopy and transmission electron microscopy. The increasing of the maximum surface pressure from 32 to 44 mN/m takes place with decreasing the temperature from 34 to 11°C. This is due to a decrease in the rate of dissolution of surfactant molecules in water. The increasing of a filling degree of monolayer by the quantum dots and increasing of it uniformity in thickness takes place in this temperature range. The area of bilayer and multilayer film of quantum dots decreasing and the area of quantum dots monolayer is increasing. This change explained by the difference in the phase condition of oleic acid molecules, which stabilized quantum dots.

  5. Influence of probe-sample temperature difference on thermal mapping contrast in scanning thermal microscopy imaging

    NASA Astrophysics Data System (ADS)

    Kaźmierczak-Bałata, Anna; Juszczyk, Justyna; Trefon-Radziejewska, Dominika; Bodzenta, Jerzy

    2017-03-01

    The purpose of this work is to investigate the influence of a temperature difference through a probe-sample contact on thermal contrast in Scanning Thermal Microscopy imaging. A variety of combinations of temperature differences in the probe-sample system were first analyzed based on an electro-thermal finite element model. The numerical analysis included cooling the sample, as well as heating the sample and the probe. Due to the simplicity in the implementation, experimental verification involved modifying the standard imaging technique by heating the sample. Experiments were carried out in the temperature range between 298 K and 328 K. Contrast in thermal mapping was improved for a low probe current with a heated sample.

  6. Drop Hammer Tests with Three Oleo Strut Models and Three Different Shock Strut Oils at Low Temperatures

    NASA Technical Reports Server (NTRS)

    Kranz, M

    1954-01-01

    Drop hammer tests with different shock strut models and shock strut oils were performed at temperatures ranging to -40 C. The various shock strut models do not differ essentially regarding their springing and damping properties at low temperatures; however, the influence of the different shock strut oils on the springing properties at low temperatures varies greatly.

  7. Resistivity Variation due to CO2 Migration in Different Temperature and Pressure Conditions

    NASA Astrophysics Data System (ADS)

    Nakatsuka, Y.; Onishi, K.; Yamada, Y.; Matsuoka, T.; Xue, Z.

    2007-12-01

    CO2 geological sequestration is one of the effective approaches solving the global warming problem. Captured CO2 is injected to the deep aquifers or depleted oil and gas fields. Injected CO2 migrates thorough the reservoir rock, however, the details behavior of injected CO2 under the ground at super critical phase is not yet fully understood. Migration of injected CO2 will change by the condition of the injected reservoir such as the temperature and pressure. Also density and permeability of the rock may be changed due to temperature or pressure variations. These changes control the migration behavior of injected CO2. In this study, experiments of resistivity measurements were conducted to detect the migration difference of CO2 in different temperature and pressure conditions by using sandstone core samples. Core sample was taken from Berea sandstone and processed to 5cm diameter and 12cm length. For the resistivity measurement, impression electrode was set on the both end and the measurement electrode of ring condition was set on the side of the rock sample. We stetted the core sample in the pressure vessel and recreated the condition of underground reservoir which is high pressure and high temperature. We injected supercritical CO2 in different pressure and temperature for each experiment. Pressure was changed in range of 8 to 11MPa and temperature was changed in range of 35° to 45°. This means that all the experiments were conducted in supercritical phase. From the measured resistivity variation, we verified the migration of CO2 and compared the migration behavior of CO2 in different conditions.

  8. Effect of temperature on the intrinsic viscosity and conformation of different pectins

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effects of temperature on the intrinsic viscosity and on the conformation of different pectins obtained from citrus, apple and sunflower in a 0.17M NaCl solution were studied. The intrinsic viscosity and the flow activation energy of the polymer (Ea) derived from slope of d In [']/ d(l/T) as an ...

  9. The Effect of Storage at Three Different Temperatures on the Activity of Lipase Solution.

    ERIC Educational Resources Information Center

    Bradley, Karen; Mathewman, David

    1984-01-01

    Presented are procedures used to assay the activity of lipase during storage at three different temperatures. Since lipase solutions can decay even when refrigerated, it is recommended that the enzyme be freshly prepared prior to laboratory sessions in which they are used. (JN)

  10. [Temperature compensation strategy and implementation for photoelectric modulation interferometer with large optical path difference].

    PubMed

    Wang, Yan-Chao; Wang, Zhi-Bin; Zhang, Ji-Long; Chen, You-Hua

    2013-05-01

    For temperature drift in hypervelocity photoelectric modulation interferometer, a control model of temperature compensation is presented including voltage and phase compensation. First, according to the similar and modeling theory, an equivalent circuit model of mechanical properties of hypervelocity photoelectric modulation interferometer was established, the impact of temperature drift on its resonance frequency was analyzed, a mathematical model was set up, which contains drive voltage, frequency and resonance frequency, and the control method was determined for high optical path difference to get steady. Then, a digital method including voltage and phase compensation is given for optical path difference deviation control, which merges the DPLL and program of voltage and phase compensation. Finally, the control method was tested through experiment system. A test between drive control system including voltage and phase compensation and traditional drive control system was executed, using a laser doppler vibrometer to record the amount of change in optical path difference within 3 hours. Results show that the optical path difference deviation caused by temperature drift in long term is reduced by about 50%.

  11. Compositional and Mechanical Properties of Peanuts Roasted to Equivalent Colors using Different Time/Temperature Combinations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Peanuts in North America and Europe are primarily consumed after dry roasting. Standard industry practice is to roast peanuts to a specific surface color (Hunter L-value) for a given application; however, equivalent surface colors can be attained using different roast temperature/time combinations,...

  12. Effect of Different Time/Temperature Roast Combinations on Nutritional and Mechanical Properties of Peanuts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Peanuts in North America and Europe are primarily consumed after dry roasting. Standard industry practice is to roast peanuts to a specific surface color (Hunter L-value) for a given application; however, equivalent surface colors can be attained using different roast temperature/time combinations....

  13. Effects of foliage plants on human physiological and psychological responses at different temperatures

    NASA Astrophysics Data System (ADS)

    Jumeno, Desto; Matsumoto, Hiroshi

    2015-02-01

    Escalation of task demands and time pressures tends to make a worker run into work stress, which leads to mental fatigue and depression. The mental fatigue can be reduced when attention capacity is restored. Nature can serve as a source of fascination which can restore the attention capacity. People bring plants indoors so they can experience nature in their workplace. The stress and fatigue are also affected by air temperatures. The increase or decrease of temperatures from the comfort zone may induce the stress and fatigue. The objective of this study is to investigate the intervention of using foliage plants placed inside a building at different air temperature levels. The effects of foliage plants on human stress and fatigue were measured by human physiological responses such as heart rate, amylase level, electroencephalography (EEG), and the secondary task-reaction time. Several different tasks, namely typing, math and logical sequences are included in the investigation of these studies. Fifteen subjects, with the age ranged from 22 to 38 years old have participated in the study using within subject design. From the study, it is revealed that the presence of foliage plants at several temperatures have different effects on meditation, secondary task reaction time and typing accuracy. This study also revealed that the presence of plants on several types of tasks has different effects of attention which are useful for increasing work performance.

  14. Physiological and antioxidant responses of two accessions of Arabidopsis thaliana in different light and temperature conditions.

    PubMed

    Szymańska, Renata; Nowicka, Beatrycze; Gabruk, Michał; Glińska, Sława; Michlewska, Sylwia; Dłużewska, Jolanta; Sawicka, Anna; Kruk, Jerzy; Laitinen, Roosa

    2015-06-01

    During their lifetime, plants need to adapt to a changing environment, including light and temperature. To understand how these factors influence plant growth, we investigated the physiological and antioxidant responses of two Arabidopsis accessions, Shahdara (Sha) from the Shahdara valley (Tajikistan, Central Asia) in a mountainous area and Lovvik-5 (Lov-5) from northern Sweden to different light and temperature conditions. These accessions originate from different latitudes and have different life strategies, both of which are known to be influenced by light and temperature. We showed that both accessions grew better in high-light and at a lower temperature (16°C) than in low light and at 23°C. Interestingly, Sha had a lower chlorophyll content but more efficient non-photochemical quenching than Lov-5. Sha, also showed a higher expression of vitamin E biosynthetic genes. We did not observe any difference in the antioxidant prenyllipid level under these conditions. Our results suggest that the mechanisms that keep the plastoquinone (PQ)-pool in more oxidized state could play a role in the adaptation of these accessions to their local climatic conditions.

  15. Hemispheric Differences in the Temperature of the Summertime Stratosphere and Mesosphere

    DTIC Science & Technology

    2003-01-22

    measurements of the mesopause by Huaman and Balsley [1999] also led them to conclude that the austral summer was warmer than the boreal summer at mesopause...1991. Huaman , M. M., and B. B. Balsley, Differences in near-mesopause summer winds, temperatures, and water vapor at northern and southern latitudes as

  16. Effects of different temperature treatments on biological ice nuclei in snow samples

    NASA Astrophysics Data System (ADS)

    Hara, Kazutaka; Maki, Teruya; Kakikawa, Makiko; Kobayashi, Fumihisa; Matsuki, Atsushi

    2016-09-01

    The heat tolerance of biological ice nucleation activity (INA) depends on their types. Different temperature treatments may cause varying degrees of inactivation on biological ice nuclei (IN) in precipitation samples. In this study, we measured IN concentration and bacterial INA in snow samples using a drop freezing assay, and compared the results for unheated snow and snow treated at 40 °C and 90 °C. At a measured temperature of -7 °C, the concentration of IN in untreated snow was 100-570 L-1, whereas the concentration in snow treated at 40 °C and 90 °C was 31-270 L-1 and 2.5-14 L-1, respectively. In the present study, heat sensitive IN inactivated by heating at 40 °C were predominant, and ranged 23-78% of IN at -7 °C compared with untreated samples. Ice nucleation active Pseudomonas strains were also isolated from the snow samples, and heating at 40 °C and 90 °C inactivated these microorganisms. Consequently, different temperature treatments induced varying degrees of inactivation on IN in snow samples. Differences in the concentration of IN across a range of treatment temperatures might reflect the abundance of different heat sensitive biological IN components.

  17. Metabolic and Cardiovascular Responses during Aquatic Exercise in Water at Different Temperatures in Older Adults

    ERIC Educational Resources Information Center

    Bergamin, Marco; Ermolao, Andrea; Matten, Sonia; Sieverdes, John C.; Zaccaria, Marco

    2015-01-01

    Purpose: The aim of this study was to investigate the physiological responses during upper-body aquatic exercises in older adults with different pool temperatures. Method: Eleven older men (aged 65 years and older) underwent 2 identical aquatic exercise sessions that consisted of 3 upper-body exercises using progressive intensities (30, 35, and 40…

  18. Grazing Characteristics and Growth Efficiencies at Two Different Temperatures for Three Nanoflagellates Fed with Vibrio Bacteria at Three Different Concentrations.

    PubMed

    Ishigaki, T.; Sleigh, M.A.

    2001-04-01

    Small inocula of one of the flagellates Paraphysomonas imperforata, Pteridomonas danica, and Cafeteria roenbergensis were added to suspensions of the bacterium Vibrio natriegens at each of three concentrations between 107 and 108 cells ml-1 and incubated at each of the temperatures 10 degrees C and 25 degrees C. Samples were taken at intervals for counting the flagellates and bacteria to determine the timing of the maximum of flagellate numbers and the concentrations at that time. Measurements of the protein concentration of the suspensions during incubation were used to determine the gross growth efficiency (GGE) or yield of flagellate grazing in each experiment. The most effective grazer was Pteridomonas, followed by Paraphysomonas, with Cafeteria being least effective, as judged by the threshold bacterial concentrations at which flagellate multiplication ceased, which were about 2 x 105, 2 x 106, and 2 x 107, respectively, and by the finding that Pteridomonas consumed 99%, Paraphysomonas about 95%, and Cafeteria only 60-70% of the available bacteria in the experiments. Peak concentrations of flagellates were reached later at the lower temperature, but the numbers of flagellates produced and of bacteria eaten were of a similar order at the two temperatures and the GGE was only slightly higher at the lower temperature. The time taken to reach peak flagellate numbers changed little with a threefold increase in bacterial concentrations, but the GGE increased and the numbers of bacteria eaten to produce one flagellate decreased when the bacterial concentration was increased. The three flagellates show clear evidence of niche specialization in differences in thresholds of bacterial prey concentration.

  19. Physiological and biochemical responses of Ricinus communis seedlings to different temperatures: a metabolomics approach

    PubMed Central

    2014-01-01

    Background Compared with major crops, growth and development of Ricinus communis is still poorly understood. A better understanding of the biochemical and physiological aspects of germination and seedling growth is crucial for the breeding of high yielding varieties adapted to various growing environments. In this context, we analysed the effect of temperature on growth of young R. communis seedlings and we measured primary and secondary metabolites in roots and cotyledons. Three genotypes, recommended to small family farms as cash crop, were used in this study. Results Seedling biomass was strongly affected by the temperature, with the lowest total biomass observed at 20°C. The response in terms of biomass production for the genotype MPA11 was clearly different from the other two genotypes: genotype MPA11 produced heavier seedlings at all temperatures but the root biomass of this genotype decreased with increasing temperature, reaching the lowest value at 35°C. In contrast, root biomass of genotypes MPB01 and IAC80 was not affected by temperature, suggesting that the roots of these genotypes are less sensitive to changes in temperature. In addition, an increasing temperature decreased the root to shoot ratio, which suggests that biomass allocation between below- and above ground parts of the plants was strongly affected by the temperature. Carbohydrate contents were reduced in response to increasing temperature in both roots and cotyledons, whereas amino acids accumulated to higher contents. Our results show that a specific balance between amino acids, carbohydrates and organic acids in the cotyledons and roots seems to be an important trait for faster and more efficient growth of genotype MPA11. Conclusions An increase in temperature triggers the mobilization of carbohydrates to support the preferred growth of the aerial parts, at the expense of the roots. A shift in the carbon-nitrogen metabolism towards the accumulation of nitrogen-containing compounds seems

  20. Temperature Values Variability in Piezoelectric Implant Site Preparation: Differences between Cortical and Corticocancellous Bovine Bone

    PubMed Central

    Lamazza, Luca; Garreffa, Girolamo; Laurito, Domenica; Lollobrigida, Marco; Palmieri, Luigi; De Biase, Alberto

    2016-01-01

    Purpose. Various parameters can influence temperature rise and detection during implant site preparation. The aim of this study is to investigate local temperature values in cortical and corticocancellous bovine bone during early stages of piezoelectric implant site preparation. Materials and Methods. 20 osteotomies were performed using a diamond tip (IM1s, Mectron Medical Technology, Carasco, Italy) on two different types of bovine bone samples, cortical and corticocancellous, respectively. A standardized protocol was designed to provide constant working conditions. Temperatures were measured in real time at a fixed position by a fiber optic thermometer. Results. Significantly higher drilling time (154.90 sec versus 99.00 sec; p < 0.0001) and temperatures (39.26°C versus 34.73°C; p = 0.043) were observed in the cortical group compared to the corticocancellous group. A remarkable variability of results characterized the corticocancellous blocks as compared to the blocks of pure cortical bone. Conclusion. Bone samples can influence heat generation during in vitro implant site preparation. When compared to cortical bone, corticocancellous samples present more variability in temperature values. Even controlling most experimental factors, the impact of bone samples still remains one of the main causes of temperature variability. PMID:27110567

  1. Fitness costs associated with different frequencies and magnitudes of temperature change in the butterfly Bicyclus anynana.

    PubMed

    Franke, Kristin; Heitmann, Nadja; Tobner, Anne; Fischer, Klaus

    2014-04-01

    Plastic responses to changes in environmental conditions are ubiquitous and typically highly effective, but are predicted to incur costs. We here investigate the effects of different frequencies and magnitudes of temperature change in the tropical butterfly Bicyclus anynana, considering developmental (Experiment 1) and adult stage plasticity (Experiment 2). We predicted negative effects of more frequent temperature changes on development, immune function and/or reproduction. Results from Experiment 1 showed that repeated temperature changes during development, if involving large amplitudes, negatively affect larval time, larval growth rate and pupal mass, while adult traits remained unaffected. However, results from treatment groups with smaller temperature amplitudes yielded no clear patterns. In Experiment 2 prolonged but not repeated exposure to 39°C increased heat tolerance, potentially reflecting costs of repeatedly activating emergency responses. At the same time fecundity was more strongly reduced in the group with prolonged heat stress, suggesting a trade-off between heat tolerance and reproduction. Clear effects were restricted to conditions involving large temperature amplitudes or high temperatures.

  2. Modeling Allometric Relationships in Leaves of Young Rapeseed (Brassica napus L.) Grown at Different Temperature Treatments

    PubMed Central

    Tian, Tian; Wu, Lingtong; Henke, Michael; Ali, Basharat; Zhou, Weijun; Buck-Sorlin, Gerhard

    2017-01-01

    Functional–structural plant modeling (FSPM) is a fast and dynamic method to predict plant growth under varying environmental conditions. Temperature is a primary factor affecting the rate of plant development. In the present study, we used three different temperature treatments (10/14°C, 18/22°C, and 26/30°C) to test the effect of temperature on growth and development of rapeseed (Brassica napus L.) seedlings. Plants were sampled at regular intervals (every 3 days) to obtain growth data during the length of the experiment (1 month in total). Total leaf dry mass, leaf area, leaf mass per area (LMA), width-length ratio, and the ratio of petiole length to leaf blade length (PBR), were determined and statistically analyzed, and contributed to a morphometric database. LMA under high temperature was significantly smaller than LMA under medium and low temperature, while leaves at high temperature were significantly broader. An FSPM of rapeseed seedlings featuring a growth function used for leaf extension and biomass accumulation was implemented by combining measurement with literature data. The model delivered new insights into growth and development dynamics of winter oilseed rape seedlings. The present version of the model mainly focuses on the growth of plant leaves. However, future extensions of the model could be used in practice to better predict plant growth in spring and potential cold damage of the crop. PMID:28377775

  3. Nutrient transformation during aerobic composting of pig manure with biochar prepared at different temperatures.

    PubMed

    Li, Ronghua; Wang, Quan; Zhang, Zengqiang; Zhang, Guangjie; Li, Zhonghong; Wang, Li; Zheng, Jianzhong

    2015-01-01

    The effects of the corn stalk charred biomass (CB) prepared at different pyrolysis temperatures as additives on nutrient transformation during aerobic composting of pig manure were investigated. The results showed that the addition of CB carbonized at different temperatures to pig manure compost significantly influenced the compost temperature, moisture, pH, electrical conductivity, organic matter degradation, total nitrogen, [Formula: see text] and NH3 variations during composting. Compared with control and adding CB charred at lower temperature treatments, the addition of CB prepared over 700°C resulted in higher pH (over 9.2) and NH3 emission and lower potherb mustard seed germination index value during the thermophilic phase. Peak temperatures of composts appeared at 7 days for control and 11 days for CB added treatments. During 90 days composting, the organic matter degradation could be increased over 14.8-29.6% after adding of CB in the compost mixture. The introduction of CB in pig manure could prolong the thermophilic phase, inhibit moisture reduce, facilitate the organic matter decomposition, reduce diethylene triamine pentaacetic acid (DTPA) extractable Zn and Cu contents in pig manure composts and increase ryegrass growth. The study indicated that the corn stalk CB prepared around 500°C was a suitable additive in pig manure composting.

  4. Difference in ocular surface temperature by infrared thermography in phakic and pseudophakic patients

    PubMed Central

    Sniegowski, Matthew; Erlanger, Michael; Velez-Montoya, Raul; Olson, Jeffrey L

    2015-01-01

    Purpose To assess the change in ocular surface temperature between healthy phakic and pseudophakic patients. Methods We included patients with no history of ocular disease other than cataract. Patients were divided into three groups: clear lens, cataract, and pseudophakic. All patients had two ocular surface digital thermal scans. An average of five surface points was used as the mean ocular surface temperature. Results were analyzed with a one-way analysis of variance and a Tukey’s least significance difference test. The patients were further divided into phakic and pseudophakic groups. Correlation coefficients between several variables were done in order to assess dependencies. Results Fifty-six eyes (28 cataracts, 12 clear lenses, 16 pseudophakic) were enrolled. The mean ocular surface temperature in the cataract group was 34.14°C±1.51°C; clear lens: 34.43°C±2.27°C; and pseudophakic: 34.97°C±1.57°C. There were no statistical differences among the study groups (P=0.3). There was a nonsignificant negative correlation trend between age and surface temperature in the phakic group. The trend inverted in the pseudophakic group but without statistical significance. Conclusion Although cataract extraction and intraocular lens implantation seem to induce a mild increase in ocular surface temperature, the effect is not clear and not significant. PMID:25834383

  5. Biological Strategies of Dermestes maculatus DeGeer (Coleoptera: Dermestidae) at Larval Stages in Different Temperatures.

    PubMed

    Zanetti, N I; Visciarelli, E C; Centeno, N D

    2016-12-01

    The intraspecific variation in larval instars is a widely distributed phenomenon amongst holometabolous insects. Several factors can affect the number of instars, such as temperature, humidity, and density. Only a few references could be found in the literature because the invariability in the number of larval instars is considered normal, and the issue has raised little to no interest. Despite this, no study to date has intended to assess or focus on the larval development. Here, we analyzed the effect of different rearing temperature on the larval stage of Dermestes maculatus DeGeer (Coleoptera: Dermestidae). The results indicated that at all temperatures, L5 represented a decisive point for individuals as well as the other later larval instars, because the next step to follow was to pupate or molt to the next larval instar. Furthermore, there were mainly two populations, L5 and L6, although in different proportions according to temperature. We also found that at a greater number of instars, the larval development at all temperatures lasted longer. Moreover, the exponential model was the best adjustment in the developmental time of all populations as well as for the accumulated developmental time of L1-L4. Thus, we conclude that random factors such as genetics could probably cause interspecific variability in D. maculatus larval development.

  6. Thermal Band Characterization of LANDSAT-4 Thematic Mapper. [Buffalo, New York and water temperature in Lake Erie

    NASA Technical Reports Server (NTRS)

    Lansing, J. C.; Barker, J. L.

    1984-01-01

    A quick look monitor in the spacecraft control center was used to measure the TM Band 6 shutter background and the 34.7 C internal blackbody signal on over 50 dates. Comparison of relative internal gains between the four channels to prelaunch values showed changes over 9 months of up to 5%, while 512 x 512 subsections of the original 10 daytime scenes showed scene counts that ranged from 135 down to 62. A night scene of the Buffalo area was used to determine channel gain relative to the mean and to discern a systematic along scan pattern in a difference between forward and reverse scan counts of up to 0.5. A corrected digital image was produced and individual gains and offsets were calculated for the four channels. At satellite radiance was determine and noise equivalent temperature difference was calculated. The calibration data and the Buffalo scene, with the corrections and estimates of the atmospheric transmission and radiance, were used to make a temperature estimate for an area of Lake Erie of 21 C to 27 C. Local records of the temperature showed 21 C.

  7. Developmental Biology of Zeugodacus cucurbitae (Diptera: Tephritidae) in Three Cucurbitaceous Hosts at Different Temperature Regimes

    PubMed Central

    Mkiga, A. M.; Mwatawala, M. W

    2015-01-01

    Fruit flies are key pests of cucurbits in many parts of the world, including Tanzania. Developmental biology of Zeugodacus cucurbitae (Coquillett) has been determined across temperature regimes in some cucurbitaceous hosts, in limited geographies. This study was conducted to determine duration and survival rates of immature stages of Z. cucurbitae in three cucurbitaceous hosts, at different temperature regimes. It was hypothesized that temperature and cucurbitaceous hosts influence duration and survival of immature stages of Z. cucurbitae. We conducted experiments in the environmental chamber set at 75 ± 10% RH and a photoperiod of 12:12 (L:D) h, at temperatures of 20, 25, and 30°. Our results showed that duration and survival of immature stages of Z. cucurbitae differed significantly among the temperature regimes but not among the hosts. Egg incubation period as well as larval and pupal stages were significantly longer (P < 0.0001) at low temperature in all three hosts Likewise, survival rate of all immature stages were significantly higher (P < 0.0001) at higher than lower temperatures. The three hosts, cucumber (Cucumis sativus), watermelon (Citrullus lanatus (Thunb.) Matsum. and Nakai), and pumpkin (Cucurbita pepo) did not significantly affect duration or survival rates of immature stages of Z. cucurbitae. The low developmental thresholds were estimated at 15.88, 13.44, and 12.62 for egg, larva and pupa, respectively. These results further confirm that Z. cucurbitae is well adapted to warm climate, which dominates many areas of Tanzania. PMID:26589874

  8. Effects of Urban Morphology on Intra-Urban Temperature Differences: Two Squares in Glasgow City Centre

    NASA Astrophysics Data System (ADS)

    Drach, P. R. C.; Emmanuel, R.

    2014-12-01

    The perspective of climate change increases the necessity of tackling the urban over heating effects, by developing strategies to mitigate/adapt to changes. Analysing the influence of urban form on intra-urban temperature dynamics could be a helpful way of reducing its negative consequences. Also, it would help untangle the urban effect from the effect caused by atmospheric conditions. The present paper presents the effect of atmospheric conditions as exemplified by atmospheric stability (modified Pasquill-Gifford-Turner classification system) and urban morphology as measured by the Sky View Factor (SVF) on intra-urban variations in air temperature in a cold climate city, in and around the mature urban area of Glasgow, UK (55° 51' 57.294"N, 4° 15' 0.2628"W). The aim is to highlight their combined importance and to make preliminary investigations on the local warming effect of urban morphology under specific atmospheric stability classes. The present work indicates that the maximum intra-urban temperature differences (i.e. temperature difference between the coolest and the warmest spots in a given urban region) is strongly correlated with atmospheric stability. The spatial patterns in local temperature variations consistently show that water bodies and urban parks have lower temperature variations. Thus, greenery and urban materials could play an important role in influencing the local climate in cold cities. The knowledge of urban morphology's influence on local temperature variations could be an important tool for devising appropriate planning/design strategies to face urban overheating in the coming years as the background climate continues to warm.

  9. [Adsorption of Cd(II) varies with biochars derived at different pyrolysis temperatures].

    PubMed

    Wang, Zhen-Yu; Liu, Guo-Cheng; Monica, Xing; Li, Feng-Min; Zheng, Hao

    2014-12-01

    Ten biochars were prepared at different pyrolysis temperatures (300- 600 degrees C) using peanut shells and Chinese medicine material residue as raw materials, and were characterized. Adsorption behavior of Cd(II) on these biochars at different solution pHs, sorption times, and Cd(II) concentrations was investigated. The C content, surface area, and aromaticity of the biochars increased with increasing pyrolysis temperature, while the amount of oxygen-containing functional groups decreased. In addition, the content of inorganic minerals (e. g., Ca/Mg carbonate or phosphate) was enriched, but their solubility was reduced with increasing pyrolysis temperature. As the solution pHs increased from 2.0 to 6.0, the amount of Cd(II) adsorbed on the biochars gradually increased, and achieved the maximum at pH 6.0. Adsorption processes could be divided into two stages: fast and slow sorption. The rate of Cd(II) adsorption on these biochars was regulated by film and intraparticle diffusion, precipitation and ion exchange. With increasing temperature, the percentage of fast sorption to overall sorption of Cd(II) gradually decreased. Sharp decrease of oxygen-containing functional groups and formation of insoluble crystalline minerals reduced the rate of fast sorption on the high-temperature biochars (> 500 degrees C). For low-temperature biochars (≤ 400 degrees C), precipitation and ion exchange were the dominant sorption mechanisms. For high-temperature biochars (≥ 500 degrees C), more integrated π-conjugated aromatic structures enhanced the contribution of Cd-π interaction to the overall sorption, but the formation of phosphate and carbonate minerals probably weakened the sorption. These results will provide important information on screening biochars as engineered adsorbents to remove or immobilize Cd(II) in contaminated water and soil.

  10. Proteinase and phospholipase activities and development at different temperatures of yeasts isolated from bovine milk.

    PubMed

    Melville, Priscilla A; Benites, Nilson R; Ruz-Peres, Monica; Yokoya, Eugenio

    2011-11-01

    The presence of yeasts in milk may cause physical and chemical changes limiting the durability and compromising the quality of the product. Moreover, milk and dairy products contaminated by yeasts may be a potential means of transmission of these microorganisms to man and animals causing several kinds of infections. This study aimed to determine whether different species of yeasts isolated from bovine raw milk had the ability to develop at 37°C and/or under refrigeration temperature. Proteinase and phospholipase activities resulting from these yeasts were also monitored at different temperatures. Five genera of yeasts (Aureobasidium sp., Candida spp., Geotrichum spp., Trichosporon spp. and Rhodotorula spp.) isolated from bovine raw milk samples were evaluated. All strains showed one or a combination of characteristics: growth at 37°C (99·09% of the strains), psychrotrophic behaviour (50·9%), proteinase production (16·81% of the strains at 37°C and 4·09% under refrigeration) and phospholipase production (36·36% of the isolates at 37°C and 10·9% under refrigeration), and all these factors may compromise the quality of the product. Proteinase production was similar for strains incubated at 37°C (16·81% of the isolates) and room temperature (17·27%) but there was less amount of phospholipase-producing strains at room temperature (15·45% of the isolates were positive) when compared with incubation at 37°C (36·36%). Enzymes production at 37°C by yeasts isolated from milk confirmed their pathogenic potential. The refrigeration temperature was found to be most efficient to inhibit enzymes production and consequently ensure better quality of milk. The viability of yeasts and the activity of their enzymes at different temperatures are worrying because this can compromise the quality of dairy products at all stages of production and/or storage, and represent a risk to the consumer.

  11. Influence of Air Temperature Difference on the Snow Melting Simulation of SWAT Model

    NASA Astrophysics Data System (ADS)

    YAN, Y.; Onishi, T.

    2013-12-01

    The temperature-index models are commonly used to simulate the snowmelt process in mountain areas because of its good performance, low data requirements, and computational simplicity. Widely used distributed hydrological model: Soil and Water Assessment Tool (SWAT) model is also using a temperature-index module. However, the lack of monitoring air temperature data still involves uncertainties and errors in its simulation performance especially in data sparse area. Thus, to evaluate the different air temperature data influence on the snow melt of the SWAT model, five different air temperature data are applied in two different Russia basins (Birobidjan basin and Malinovka basin). The data include the monitoring air temperature data (TM), NCEP reanalysis data (TNCEP), the dataset created by inverse distance weighted interpolation (IDW) method (TIDW), the dataset created by improved IDW method considering the elevation influence (TIDWEle), and the dataset created by using linear regression and MODIS Land Surface Temperature (LST) data (TLST). Among these data, the TLST , the TIDW and TIDWEle data have the higher spatial density, while the TNCEP and TM DATA have the most valid monitoring value for daily scale. The daily simulation results during the snow melting seasons (March, April and May) showed reasonable results in both test basins for all air temperature data. While R2 and NSE in Birobidjan basin are around 0.6, these values in Malinovka basin are over 0.75. Two methods: Generalized Likelihood Uncertainty Estimation (GLUE) and Sequential Uncertainty Fitting, version. 2 (SUFI-2) were used for model calibration and uncertainty analysis. The evolution index is p-factor which means the percentage of measured data bracketed by the 95% Prediction Uncertainty (95PPU). The TLST dataset always obtained the best results in both basins compared with other datasets. On the other hand, the two IDW based method get the worst results among all the scenarios. Totally, the

  12. Effects of different dentin thicknesses and air cooling on pulpal temperature rise during laser welding.

    PubMed

    Secilmis, Asli; Bulbul, Mehmet; Sari, Tugrul; Usumez, Aslihan

    2013-01-01

    The neodymium/yttrium-aluminum-garnet (Nd/YAG) laser has been suggested to repair broken prostheses in the mouth. This study investigated the effects of different dentin thicknesses and air cooling on pulpal temperature rise during laser welding. Three intact human maxillary molars were prepared for full-veneer crown. For each tooth, dentin thicknesses in mesiobuccal cusp was 2, 3, or 4 mm. Twenty dies were duplicated from each of the prepared teeth. For metal copings with 0.5-mm thickness, wax patterns were prepared with dip wax technique directly onto each of dies. All patterns were sprued and invested. The castings were made using a nickel-chromium alloy (Nicromed Premium, Neodontics). A hole with 0.5-mm diameter was prepared on the mesiobuccal cusp of each crown. The Nd/YAG laser (9.85 W; 1 Hz repetition rate; fluence, 1.230 J/cm(2); Fidelis Plus 3, Fotona) was used for welding with or without air cooling (n = 10). The temperature rise was measured in pulpal chamber with a J-type thermocouple wire that was connected to a data logger. Differences between start and highest temperature reading were taken, and temperature rise values were compared using two-way analysis of variance and Tukey's honestly significant difference tests (α = .05). Pulpal temperature rise varied significantly depending on the dentin thickness and air cooling (p < 0.05). The non-air cooling group induced significantly the highest temperature increases. There were no significant differences between 2- and 3-mm dentin thicknesses groups (p > 0.05); however, pulpal temperature rise was the lowest for 4-mm dentin thickness group (p < 0.05). The highest values of thermal increase were found in the pulp chamber (6.8°C) when no air cooling was used in 2-mm dentin thickness group. Laser welding on base metal castings with Nd/YAG laser can be applied with air cooling to avoid temperature rises known to adversely affect pulpal health when dentin thickness is 2 or 3 mm.

  13. Shelf-life of almond pastry cookies with different types of packaging and levels of temperature.

    PubMed

    Romeo, F V; De Luca, S; Piscopo, A; Santisi, V; Poiana, M

    2010-06-01

    Almond pastries are typical cookies of the south of Italy. Introduction of new packaging for this kind of cookies requires shelf-life assessments. This study, related to different types of packaging under various storage conditions of time and temperature, identifies critical parameters, as color and texture, to track during storage studies and to extend the shelf-life. The cookies were packed in three different ways and stored at two different temperatures. The pastries were separately stored: (1) in polyvinylchloride film; (2) in aluminum foil (ALL); (3) with modified atmosphere (MAP) in plastic vessels sealed into a polyamide/ polyethylene film; and (4) in vessels without any polymeric film. The storage temperatures were 20 and 30 °C. Evolution of texture, water activity, dry matter and color was assessed. Texture was evaluated by a texture analyzer with a puncturing test. Indices for hardening were the area under the curve (N × mm) up to 10 mm of distance, and the maximum force (N) corresponding to the crust fracture. The best results were obtained with ALL packaging and MAP condition, and above all, in all the trials a temperature of 30 °C reduced the crust hardness.

  14. Plant Canopy Temperature and Heat Flux Profiles: What Difference Does an Isothermal Skin Make?

    NASA Astrophysics Data System (ADS)

    Crago, R. D.; Qualls, R. J.

    2015-12-01

    Land surface temperature Ts plays a vital role in the determination of sensible (H) and latent heat flux, upwelling long-wave radiation, and ground heat flux. While it is widely recognized that there is a range of skin temperatures represented in even a homogeneous canopy, it is often necessary or convenient to treat the surface as isothermal. This study investigates, at the sub-canopy scale, the implications of assuming that a canopy is isothermal. The focus is on profiles within the canopy of air, foliage, and soil surface temperature, and of sensible and latent heat flux source strength. Data from a dense grassland at the Southern Great Plains experiment in 1997 (SGP97) were used to assess the ability of a multi-layer canopy model to match measured sensible and latent heat fluxes along with radiometric surface temperatures. In its standard mode, the model solves the energy balance for each canopy layer and uses Localized Near Field (LNF) theory to model the turbulent transport. The results suggest the model captures the most important features of canopy flux generation and transport, and support its use to investigate scalar profiles within canopies. For 112 data points at SGP97, the model produced realistic temperature and sensible heat flux source profiles. In addition, it was run in a mode that seeks the isothermal (soil and foliage) skin temperature (Ti) that provides the same Hproduced by the model in its standard mode. This produces profiles of air and foliage temperature and of sensible heat source strength that differ significantly from profiles from the standard mode. Based on these simulations, realistic canopies may have a mixture of positive and negative sensible heat flux sources at various heights, typically with large contributions from the soil surface. There is frequently a discontinuity between foliage temperatures near the soil and the actual soil surface temperature. For isothermal canopies, heat sources at all levels had the same sign and

  15. Co-doped sodium chloride crystals exposed to different irradiation temperature

    SciTech Connect

    Ortiz-Morales, A.; Cruz-Zaragoza, E.; Furetta, C.; Kitis, G.; Flores J, C.; Hernandez A, J.; Murrieta S, H.

    2013-07-03

    Monocrystals of NaCl:XCl{sub 2}:MnCl{sub 2}(X = Ca,Cd) at four different concentrations have been analyzed. The crystals were exposed to different irradiation temperature, such as at room temperature (RT), solid water (SW), dry ice (DI) and liquid nitrogen (LN). The samples were irradiated with photon from {sup 60}Co irradiators. The co-doped sodium chloride crystals show a complex structure of glow curves that can be related to different distribution of traps. The linearity response was analyzed with the F(D) index. The F(D) value was less than unity indicating a sub-linear response was obtained from the TL response on the function of the dose. The glow curves were deconvoluted by using the CGCD program based on the first, second and general order kinetics.

  16. A comparative assessment of different methods for detecting inhomogeneities in Turkish temperature data set

    NASA Astrophysics Data System (ADS)

    Tayanç, Mete; Nüzhet Dalfes, H.; Karaca, Mehmet; Yenigün, Orhan

    1998-04-01

    A combination of different methods is described whereby climatological time series can be tested for inhomogeneities using relative homogeneity techniques. The method set includes graphical analysis, a non-parametric Kruskal-Wallis homogeneity test and a Wald-Wolfowitz runs test application to the annual mean difference temperature series between highly correlated stations. A series of Monte Carlo simulation studies was carried out, which determined the inhomogeneity detection efficiencies of these tests. The procedure is statistically rigorous and provides estimates of the time and magnitude of change in the mean. Its application to annual mean temperature differences series for 82 Turkish climate stations indicates that the method set is a valuable tool for testing time series.

  17. Discriminating among different tea leaves using an operating temperature-modulated tin oxide gas sensor

    NASA Astrophysics Data System (ADS)

    Rastkhadiv, Ali; Jenabi, Amin; Souri, Asma

    2016-03-01

    We report distinguishing different types of tea leaves from each other based on their aroma using a thermal shock-induced generic tin oxide gas sensor. The sensor used in this work consists of a microheater and a tin oxide pellet, both connected to outside circuitry with noble metal contacts. The heater is powered with a series of narrow high magnitude voltage impulses of predetermined thermal impacts adjusted to produce step-like temperature rises of different magnitudes on the gas sensitive pellet. The sensor is exposed to aromas collected from various types of tea leaves at different concentrations. Within 4.5 s, nine 500 ms-wide voltage pulses, each as high as 9.3 V in magnitude, are applied to the microheater. Each pulse causes a step-like temperature jump on the pellet temperature. The transient responses recorded for different tea leaves look different even after amplitude normalization. The sensor profiles are recorded, digitized, and compared with the database of previous experiences. A heuristically defined high dimensional feature vector is automatically generated for each analyte. Classifications are graphically achieved in a 3-D feature space after applying principle component analysis for dimension reduction.

  18. Lower Stratospheric Temperature Differences In Meteorological Analyses and Their Impact On Polar Processing Studies

    NASA Astrophysics Data System (ADS)

    Manney, G.; Sabutis, J.; Pawson, S.; Santee, M.; Naujokat, B.; Swinbank, R.; Gelman, M.; Ebisuzaki, W.

    Models - chemical transport models (CTMs), trajectory and Eulerian transport mod- els, microphysical models - used in polar processing studies typically rely on winds and/or temperatures from one of several meteorological analyses to drive the transport and control processes such as polar stratospheric cloud (PSC) formation and chemical reaction rates. Using different analyzed data sets to obtain temperatures and temper- ature histories can have significant consequences. A quantitative comparison of six meteorological analyses (UK Met Office, National Centers for Environmental Pre- diction/Climate Prediction Center (NCEP), NCEP/National Center for Atmospheric Research Reanalysis (REAN), Freie Universität Berlin, European Centre for Medium- Range Weather Forecasts (ECMWF), NASA Data Assimilation Office (DAO)) is pre- sented for the cold 1999-2000 and 1995-1996 Arctic winters, showing substantial dif- ferences in diagnostics related to polar processing between the different analyses. Bi- ases between analyses vary from year to year. Temperature history case studies show substantial differences using Met Office, NCEP, REAN, ECMWF, and DAO analyses. Different meteorological conditions in the comparably cold winters of 1995-1996 and 1999-2000 had a large impact on both expectations for PSC formation and on the ef- fects of discrepancies between different meteorological analyses. Met Office, NCEP, REAN, ECMWF, and DAO analyses are commonly used in modeling polar processes; the choice of analysis can strongly influence the results of such studies.

  19. Differences in the H-mode pedestal width of temperature and density

    NASA Astrophysics Data System (ADS)

    Schneider, P. A.; Wolfrum, E.; Groebner, R. J.; Osborne, T. H.; Beurskens, M. N. A.; Dunne, M. G.; Ferron, J. R.; Günter, S.; Kurzan, B.; Lackner, K.; Snyder, P. B.; Zohm, H.; the ASDEX Upgrade Team; the DIII-D Team; EFDA Contributors, JET

    2012-10-01

    A pedestal database was built using data from type-I ELMy H-modes of ASDEX Upgrade, DIII-D and JET. ELM synchronized pedestal data were analysed with the two-line method. The two-line method is a bilinear fit which shows better reproducibility of pedestal parameters than a modified hyperbolic tangent fit. This was tested with simulated and experimental data. The influence of the equilibrium reconstruction on pedestal parameters was investigated with sophisticated reconstructions from CLISTE and EFIT including edge kinetic profiles. No systematic deviation between the codes could be observed. The flux coordinate system is influenced by machine size, poloidal field and plasma shape. This will change the representation of the width in different coordinates, in particular, the two normalized coordinates ΨN and r/a show a very different dependence on the plasma shape. The scalings derived for the pedestal width, Δ, of all machines suggest a different scaling for the electron temperature and the electron density. Both cases show similar dependence with machine size, poloidal magnetic field and pedestal electron temperature and density. The influence of ion temperature and toroidal magnetic field is different on each of \\Delta_{T_\\rme} and \\Delta_{n_\\rme} . In dimensionless form the density pedestal width in ΨN scales with \\rho^{0.6}_{i\\star} , the temperature pedestal width with \\beta_p,ped^{0.5} . Both widths also show a strong correlation with the plasma shape. The shape dependence originates from the coordinate transformation and is not visible in real space. The presented scalings predict that in ITER the temperature pedestal will be appreciably wider than the density pedestal.

  20. Comparison of the spores of Paenibacillus polymyxa prepared at different temperatures.

    PubMed

    Huo, Zhenhua; Zhang, Nan; Raza, Waseem; Huang, Xinqi; Yong, Xiaoyu; Liu, Yunpeng; Wang, Dandan; Li, Shuqing; Shen, Qirong; Zhang, Ruifu

    2012-05-01

    Paenibacillus polymyxa SQR-21, which is antagonistic against Fusarium oxysporum, is used as a biocontrol agent and, when mixed with organic substances for solid fermentation, produces a bioorganic fertilizer. The spores of P. polymyxa prepared at different temperatures were characterized with respect to the dipicolinic acid content, heat resistance, fatty acid composition and germination. Spores prepared at 37°C showed higher heat resistance than those prepared at 25 and 30°C. However, the germination rate was negatively correlated with the sporulation temperature. The maximum germination rate of the spores prepared at 25°C was 1.3-times higher than the spores prepared at 30°C. The sporulation temperature thus affects the resistance and germination properties of P. polymyxa spores. These results are useful for the production of improved bio-organic fertilizer.

  1. Temperature distribution of air source heat pump barn with different air flow

    NASA Astrophysics Data System (ADS)

    He, X.; Li, J. C.; Zhao, G. Q.

    2016-08-01

    There are two type of airflow form in tobacco barn, one is air rising, the other is air falling. They are different in the structure layout and working principle, which affect the tobacco barn in the distribution of temperature field and velocity distribution. In order to compare the temperature and air distribution of the two, thereby obtain a tobacco barn whose temperature field and velocity distribution are more uniform. Taking the air source heat pump tobacco barn as the investigated subject and establishing relevant mathematical model, the thermodynamics of the two type of curing barn was analysed and compared based on Fluent. Provide a reasonable evidence for chamber arrangement and selection of outlet for air source heat pump tobacco barn.

  2. Achieving nitritation in a continuous moving bed biofilm reactor at different temperatures through ratio control.

    PubMed

    Bian, Wei; Zhang, Shuyan; Zhang, Yanzhuo; Li, Wenjing; Kan, Ruizhe; Wang, Wenxiao; Zheng, Zhaoming; Li, Jun

    2017-02-01

    A ratio control strategy was implemented in a continuous moving bed biofilm reactor (MBBR) to investigate the response to different temperatures. The control strategy was designed to maintain a constant ratio between dissolved oxygen (DO) and total ammonia nitrogen (TAN) concentrations. The results revealed that a stable nitritation in a biofilm reactor could be achieved via ratio control, which compensated the negative influence of low temperatures by stronger oxygen-limiting conditions. Even with a temperature as low as 6°C, stable nitritation could be achieved when the controlling ratio did not exceed 0.17. Oxygen-limiting conditions in the biofilm reactor were determined by the DO/TAN concentrations ratio, instead of the mere DO concentration. This ratio control strategy allowed the achievement of stable nitritation without complete wash-out of NOB from the reactor. Through the ratio control strategy full nitritation of sidestream wastewater was allowed; however, for mainstream wastewater, only partial nitritation was recommended.

  3. Treatment of bilateral idiopathic trigeminal neuralgia by radiofrequency thermocoagulation at different temperatures

    PubMed Central

    Yao, Peng; Hong, Tao; Wang, Zhi-bin; Ma, Jia-ming; Zhu, Yong-qiang; Li, Hong-xi; Ding, Yuan-yuan; Jiang, Chang-lin; Pan, Shi-nong

    2016-01-01

    Abstract Radiofrequency thermocoagulation (RFT) is an effective treatment for trigeminal neuralgia, but consensus regarding an optimal treatment temperature is lacking. While treatment temperatures ranging from 60°C to 95°C have been reported, RFT at too high a temperature is often followed by serious complications, and comparative evaluations of RFT at different temperatures in a single study are rare. This current prospective cohort study was to compare immediate and long-term outcomes of RFT at varying temperatures in patients with bilateral idiopathic trigeminal neuralgia (ITN) of maxillary division of trigeminal nerve (V2), mandibular division of trigeminal nerve (V3), and V2+V3, including pain relief, complications, recurrence rate, and patient satisfaction. From May 2011 to April 2016, 62 consecutive patients with bilateral ITN of V2, V3, and V2+V3 were enrolled in the study. These patients underwent bilateral RFT at 68°C and 75°C, respectively, using the same RF parameters. Side-to-side results, including pain relief, complications, and patient satisfaction, were compared during a 5-year follow-up period. Overall pain relief was satisfactory after RFT. The rate of pain relief after treatment at 75°C was slightly higher than at 68°C (P > 0.05). The pain-free rate was 95.1% at 75°C and 93.5% at 68°C at 1 year, 84.3% and 78.1% at 3 years, and 80.7% and 74.4% at 5 years. There were 10 and 13 cases of recurrence, respectively, and 6 cases of bilateral recurrence. The incidence and severity of complications were greater at 75°C (P < 0.05) than at 68°C, and therefore the patient satisfaction at the higher temperature was lower (P < 0.05). Patients with bilateral ITN who underwent RFT at different temperatures had consistent pain relief after RFT at both 75°C and 68°C, but there were fewer and less severe complications at 68°C, which was accompanied by greater patient satisfaction. This suggests that RFT at lower temperatures may be

  4. Concentration of Umami Compounds in Pork Meat and Cooking Juice with Different Cooking Times and Temperatures.

    PubMed

    Rotola-Pukkila, Minna K; Pihlajaviita, Seija T; Kaimainen, Mika T; Hopia, Anu I

    2015-12-01

    This study examined the concentrations of umami compounds in pork loins cooked at 3 different temperatures and 3 different lengths of cooking times. The pork loins were cooked with the sous vide technique. The free amino acids (FAAs), glutamic acid and aspartic acid; the 5'-nucleotides, inosine-5'-monophosphate (IMP) and adenosine-5'-monophosphate (AMP); and corresponding nucleoside inosine of the cooked meat and its released juice were determined by high-performance liquid chromatography. Under the experimental conditions used, the cooking temperature played a more important role than the cooking time in the concentration of the analyzed compounds. The amino acid concentrations in the meat did not remain constant under these experimental conditions. The most notable effect observed was that of the cooking temperature and the higher amino acid concentrations in the released juice of meat cooked at 80 °C compared with 60 and 70 °C. This is most likely due to the heat induced hydrolysis of proteins and peptides releasing water soluble FAAs from the meat into the cooking juice. In this experiment, the cooking time and temperature had no influence on the IMP concentrations observed. However, the AMP concentrations increased with the increasing temperature and time. This suggests that the choice of time and temperature in sous vide cooking affects the nucleotide concentration of pork meat. The Sous vide technique proved to be a good technique to preserve the cooking juice and the results presented here show that cooking juice is rich in umami compounds, which can be used to provide a savory or brothy taste.

  5. Skin and bulk temperature difference at Lake Tahoe: A case study on lake skin effect

    NASA Astrophysics Data System (ADS)

    Wilson, R. Chris; Hook, Simon J.; Schneider, Philipp; Schladow, S. Geoffrey

    2013-09-01

    water, infrared radiometers on satellites measure radiation leaving from the surface skin layer and therefore the retrieved temperature is representative of the skin layer. This is slightly different from the bulk layer deeper in the water where various floating thermometers take temperature measurements to validate satellite measurements. The difference between the bulk and skin temperature (skin effect) must be understood to properly validate schemes that use surface skin temperature to infer bulk temperatures. Further skin temperatures retrieved over inland waters may show different patterns to those retrieved over oceans due to differences in conditions such as wind speed, aerosols, and elevation. We have analyzed the differences between the skin and bulk temperatures at four permanent monitoring stations (buoys) located on Lake Tahoe since 1999 and compared the results with similar studies over the ocean typically obtained from boat cruises. Skin effect distributions were found to be consistent across the buoys; however, the diurnal behavior of the skin effect was slightly different and shown to be related to wind speed measured at an individual buoy. When wind speed was less than 2 m s-1, the skin temperature osclillated and greatly increased the uncertainty in the skin effect reported over Lake Tahoe. When downwelling sky radiation was increased from clouds or high humidity, this led to nighttime skin temperatures that were warmer than bulk temperatures by as much as 0.5 K. The size of the warm skin effect is larger than other ocean studies that observed warm nighttime skin values around 0.1 K. The nighttime skin effect was seen to be more consistent with a smaller standard deviation compared to the daytime skin effect. The nighttime skin behavior had a mean and standard deviation that ranged between 0.3 and 0.5 K and between 0.3 and 0.4 K, respectively. In contrast, daytime skin effect was strongly influenced by direct solar illumination and typically had a

  6. Fabrication and properties of YBa2Cu3O7- x ceramics at different sintering temperatures

    NASA Astrophysics Data System (ADS)

    Prayoonphokkharat, Poom; Jiansirisomboon, Sukanda; Watcharapasorn, Anucha

    2013-07-01

    The influence of sintering temperatures on the fabrication of YBCO ceramics under normal air atmosphere was investigated in this study. YBCO ceramics were prepared by mixing starting compounds of Y2O3, BaCO3 and CuO powders, which were calcined at 850°C for 12 h. The powder was pelletized and sintered at different temperatures, from 930°C-1050°C, for 12 h. Phase identification was carried out by x-ray diffraction (XRD) technique. Scanning electron microscopy (SEM) with energy dispersive x-ray analysis (EDS) was used to study microstructure and chemical composition. In addition, density, Vickers hardness properties, the change of resistance and dielectric properties with temperature above T c were investigated. It was found that, at 950°C-1000°C, high-purity YBCO ceramic could be obtained. Outside this temperature range, either impurity phases were present or melting occurred. SEM images showed that grain size, which ranged from 1.5-2.5 µm, and hardness were related to density and liquid phase present in the sample. Furthermore, the sintering temperature affected oxygen content which, in turn, determined the conductive or semi-conductive behavior observed by electrical property measurement.

  7. Specific electrical capacitance and voltage breakdown as a function of temperature for different planar lipid bilayers.

    PubMed

    Velikonja, Aljaž; Kramar, Peter; Miklavčič, Damijan; Maček Lebar, Alenka

    2016-12-01

    The breakdown voltage and specific electrical capacitance of planar lipid bilayers formed from lipids isolated from the membrane of archaeon Aeropyrum pernix K1 as a function of temperature were studied and compared with data obtained previously in MD simulation studies. Temperature dependence of breakdown voltage and specific electrical capacitance was measured also for dipalmitoylphosphatidylcholine (DPPC) bilayers and bilayers formed from mixture of diphytanoylphosphocholine (DPhPC) and DPPC in ratio 80:20. The breakdown voltage of archaeal lipids planar lipid bilayers is more or less constant until 50°C, while at higher temperatures a considerable drop is observed, which is in line with the results from MD simulations. The breakdown voltage of DPPC planar lipid bilayer at melting temperature is considerably higher than in the gel phase. Specific electrical capacitance of planar lipid bilayers formed from archaeal lipids is approximately constant for temperatures up to 40°C and then gradually decreases. The difference with MD simulation predictions is discussed. Specific electrical capacitance of DPPC planar lipid bilayers in fluid phase is 1.75 times larger than that of the gel phase and it follows intermediated phases before phase transition. Increase in specific electrical capacitance while approaching melting point of DPPC is visible also for DPhPC:DPPC mixture.

  8. Antioxidant activities of orange peel extract in ghee (butter oil) stored at different storage temperatures.

    PubMed

    Asha, A; Manjunatha, M; Rekha, R M; Surendranath, B; Heartwin, P; Rao, J; Magdaline, E; Sinha, Chitranayak

    2015-12-01

    Antioxidant activities of butylatedhydroxyanisole (BHA) and orange peel powder extract in ghee stored at different storage temperatures (T1:6 ± 2 °C; T2: 32 ± 2 °C; T3:60 ± 2 °C) were evaluated during storage period of 21 days. Peroxide value (PV), thiobarbituric acid (TBA), radical scavenging activity (RSA) and free fatty acids (FFA) of ghee samples were analyzed during the study. PV, TBA and FFA of ghee samples increased significantly while radical scavenging activity (RSA) of ghee samples decreased significantly at accelerated temperature (T3) as compared to the temperatures at T1 and T2. Effect of storage temperature on development of peroxides and TBA of ghee samples was significantly higher than the effect of treatment and storage period while treatment had more significant effect on the change in FFA and RSA as compared to storage temperature and storage period. Ghee incorporated with orange peel extract (OPE) showed stronger activity in quenching DPPH radicals and least development of PV, TBA and FFA than ghee incorporated with BHA and control. The study revealed that orange peel could be a good natural source of antioxidants which can be used in fat rich food products like ghee to retard oxidative deterioration.

  9. Effect of four different reflective barriers on black-globe temperatures in calf hutches.

    PubMed

    Friend, T H; Haberman, J A; Binion, W R

    2014-12-01

    Polyethylene hutches are a popular method of housing dairy calves from 0 to 60 or more days of age, although these hutches get hot when in full sun. This study characterized the relative differences in the ability of four different types of radiant barriers to reduce black-globe temperature within these hutches. Treatments included three different types of covers (two types of laminates (Cadpak P and Cadpak ESD) and an aluminized 3.0-mil white low-density polyethylene (LDPE)) and a reflective paint (LO/MIT-1). The reflective covers were 1.8 × 3 m finished size, and covered the top and sides of the hutch down to 0.15 m above the ground, leaving the front and back exposed. The LO/MIT-1 paint covered the entire sides and roof of the hutch. Two 24-h trials 1 week apart were conducted during relatively hot and clear days in early August. Black-globe temperatures were recorded in duplicate and averaged at 20-min intervals using blackened table tennis balls mounted 0.3 m above the floor in the center of each hutch. Ambient temperature (shade) during the hottest 2-h period for both trials averaged 39.9 °C while the uncovered control averaged 41.1 °C, and LO/MIT-1 averaged 39.9 °C; both of which were significantly higher (P < 0.01) than the Cadpak P (38.9 °C), Cadpak ESD (38.6 °C), and aluminized LDPE (38.7 °C). During periods of high solar radiation, the hutches with covers had lowest black-globe temperatures followed by hutches painted with reflective paint, while control hutches had the highest temperature.

  10. Antioxidant and oxidative stress responses of sojourners at high altitude in different climatic temperatures

    NASA Astrophysics Data System (ADS)

    Sinha, Sanchari; Singh, Som Nath; Saha, Mantu; Kain, T. C.; Tyagi, A. K.; Ray, Uday Sankar

    2010-01-01

    High altitude (HA) is a multi-stressor environment comprising hypobaric hypoxia and cold. Climatic temperature varies with seasonal variation at HA. The present study was undertaken to investigate the effect of ambient temperature on antioxidant profile among sojourners at HA. The study was conducted on sojourners exposed to an altitude of 4,560 m in two different seasons and categorized into two groups (SOJ 1, n = 63, ambient temp. at HA: -6º to +10ºC; SOJ 2, n = 81, ambient temp. at HA: 3º-22ºC). Blood was collected at sea level (SL) and after 4 weeks of HA exposure. Antioxidant enzymes showed significant upregulation in SOJ 2 at HA. In SOJ 1, superoxide dismutase and glutathione peroxidase showed significant upregulation but catalase and glutathione reductase showed significant decrease at HA. Non-enzymatic antioxidants showed significant reduction in SOJ 1 whereas a sustained antioxidant profile was observed in SOJ 2 at HA. Oxidative stress markers showed higher levels in SOJ 1 than SOJ 2 at HA. Differences observed between SOJ 1 and SOJ 2 at HA may be the consequence of different environmental temperatures. Cold stress was higher in SOJ 1 as evidenced from the significantly lower oral temperature in SOJ 1 as compared to SOJ 2. Cold- and hypoxia-induced increase in energy expenditure was significantly high in SOJ 1 than SOJ 2. To conclude, chronic exposure to hypoxia in moderate climatic temperature has a potential preconditioning effect on antioxidant system, but exposure to both cold and hypoxia causes greater oxidative stress due to altered metabolic rate.

  11. Temperature control during therapeutic hypothermia for newborn encephalopathy using different Blanketrol devices.

    PubMed

    Laptook, Abbot R; Kilbride, Howard; Shepherd, Edward; McDonald, Scott A; Shankaran, Seetha; Truog, William; Das, Abhik; Higgins, Rosemary D

    2014-12-01

    Therapeutic hypothermia improves the survival and neurodevelopmental outcome of infants with newborn encephalopathy of a hypoxic-ischemic origin. The NICHD Neonatal Research Network (NRN) Whole Body Cooling trial used the Cincinnati Sub-Zero Blanketrol II to achieve therapeutic hypothermia. The Blanketrol III is now available and provides additional cooling modes that may result in better temperature control. This report is a retrospective comparison of infants undergoing hypothermia using two different cooling modes of the Blanketrol device. Infants from the NRN trial were cooled with the Blanketrol II using the Automatic control mode (B2 cohort) and were compared with infants from two new NRN centers that adopted the NRN protocol and used the Blanketrol III in a gradient mode (B3 cohort). The primary outcome was the percent time the esophageal temperature stayed between 33°C and 34°C (target 33.5°C) during maintenance of hypothermia. Cohorts had similar birth weight, gestational age, and level of encephalopathy at the initiation of therapy. Baseline esophageal temperature differed between groups (36.6°C ± 1.0°C for B2 vs. 33.9°C ± 1.2°C for B3, p<0.0001) reflecting the practice of passive cooling during transport prior to initiation of active device cooling in the B3 cohort. This difference prevented comparison of temperatures during induction of hypothermia. During maintenance of hypothermia the mean and standard deviation of the percent time between 33°C and 34°C was similar for B2 compared to B3 cohorts (94.8% ± 0.1% vs. 95.8% ± 0.1%, respectively). Both the automatic and gradient control modes of the Blanketrol devices appear comparable in maintaining esophageal temperature within the target range during maintenance of therapeutic hypothermia.

  12. Effect of four different reflective barriers on black-globe temperatures in calf hutches

    NASA Astrophysics Data System (ADS)

    Friend, T. H.; Haberman, J. A.; Binion, W. R.

    2014-12-01

    Polyethylene hutches are a popular method of housing dairy calves from 0 to 60 or more days of age, although these hutches get hot when in full sun. This study characterized the relative differences in the ability of four different types of radiant barriers to reduce black-globe temperature within these hutches. Treatments included three different types of covers (two types of laminates (Cadpak P and Cadpak ESD) and an aluminized 3.0-mil white low-density polyethylene (LDPE)) and a reflective paint (LO/MIT-1). The reflective covers were 1.8 × 3 m finished size, and covered the top and sides of the hutch down to 0.15 m above the ground, leaving the front and back exposed. The LO/MIT-1 paint covered the entire sides and roof of the hutch. Two 24-h trials 1 week apart were conducted during relatively hot and clear days in early August. Black-globe temperatures were recorded in duplicate and averaged at 20-min intervals using blackened table tennis balls mounted 0.3 m above the floor in the center of each hutch. Ambient temperature (shade) during the hottest 2-h period for both trials averaged 39.9 °C while the uncovered control averaged 41.1 °C, and LO/MIT-1 averaged 39.9 °C; both of which were significantly higher ( P < 0.01) than the Cadpak P (38.9 °C), Cadpak ESD (38.6 °C), and aluminized LDPE (38.7 °C). During periods of high solar radiation, the hutches with covers had lowest black-globe temperatures followed by hutches painted with reflective paint, while control hutches had the highest temperature.

  13. Analyzing the impact of ambient temperature indicators on transformer life in different regions of Chinese mainland.

    PubMed

    Bai, Cui-fen; Gao, Wen-Sheng; Liu, Tong

    2013-01-01

    Regression analysis is applied to quantitatively analyze the impact of different ambient temperature characteristics on the transformer life at different locations of Chinese mainland. 200 typical locations in Chinese mainland are selected for the study. They are specially divided into six regions so that the subsequent analysis can be done in a regional context. For each region, the local historical ambient temperature and load data are provided as inputs variables of the life consumption model in IEEE Std. C57.91-1995 to estimate the transformer life at every location. Five ambient temperature indicators related to the transformer life are involved into the partial least squares regression to describe their impact on the transformer life. According to a contribution measurement criterion of partial least squares regression, three indicators are conclusively found to be the most important factors influencing the transformer life, and an explicit expression is provided to describe the relationship between the indicators and the transformer life for every region. The analysis result is applicable to the area where the temperature characteristics are similar to Chinese mainland, and the expressions obtained can be applied to the other locations that are not included in this paper if these three indicators are known.

  14. Degradation of typical antibiotics during human feces aerobic composting under different temperatures.

    PubMed

    Shi, Honglei; Wang, Xiaochang C; Li, Qian; Jiang, Shanqing

    2016-08-01

    Four typical antibiotics were added to human feces for aerobic composting using batch reactors with sawdust as the bulk matrix. Under three composting temperatures (room temperature, 35 ± 2 °C and 55 ± 2 °C), decreases in the extractable concentrations of antibiotics in the compost were monitored for 20 days. As a result, the removals of extractable tetracycline and chlortetracycline were found to be more temperature-dependent than the removals of sulfadiazine and ciprofloxacin. However, more than 90 % of all of the extractable antibiotics were removed at 55 ± 2 °C. Three specific experiments were further conducted to identify the possible actions for antibiotic removal, including self-degradation in aqueous solution, composting with a moist sterile sawdust matrix without adding feces and composting with human feces and moist sterile sawdust. As a result, it was found that the removal of tetracycline and chlortetracycline was mainly due to chemical degradation in water, whereas the removal of sulfadiazine was mainly attributed to adsorption onto sawdust particles. The microbial activity of compost varied with temperature to a certain extent, but the differences were insignificant among different antibiotics. Although microbial action is important for organic matter decomposition, its contribution to antibiotic degradation was small for the investigated antibiotics, except for ciprofloxacin, which was degraded by up to 20 % due to microbial action.

  15. Spatiotemporal Divergence of the Warming Hiatus over Land Based on Different Definitions of Mean Temperature.

    PubMed

    Zhou, Chunlüe; Wang, Kaicun

    2016-08-17

    Existing studies of the recent warming hiatus over land are primarily based on the average of daily minimum and maximum temperatures (T2). This study compared regional warming rates of mean temperature based on T2 and T24 calculated from hourly observations available from 1998 to 2013. Both T2 and T24 show that the warming hiatus over land is apparent in the mid-latitudes of North America and Eurasia, especially in cold seasons, which is closely associated with the negative North Atlantic Oscillation (NAO) and Arctic Oscillation (AO) and cold air propagation by the Arctic-original northerly wind anomaly into mid-latitudes. However, the warming rates of T2 and T24 are significantly different at regional and seasonal scales because T2 only samples air temperature twice daily and cannot accurately reflect land-atmosphere and incoming radiation variations in the temperature diurnal cycle. The trend has a standard deviation of 0.43 °C/decade for T2 and 0.41 °C/decade for T24, and 0.38 °C/decade for their trend difference in 5° × 5° grids. The use of T2 amplifies the regional contrasts of the warming rate, i.e., the trend underestimation in the US and overestimation at high latitudes by T2.

  16. Spatiotemporal Divergence of the Warming Hiatus over Land Based on Different Definitions of Mean Temperature

    PubMed Central

    Zhou, Chunlüe; Wang, Kaicun

    2016-01-01

    Existing studies of the recent warming hiatus over land are primarily based on the average of daily minimum and maximum temperatures (T2). This study compared regional warming rates of mean temperature based on T2 and T24 calculated from hourly observations available from 1998 to 2013. Both T2 and T24 show that the warming hiatus over land is apparent in the mid-latitudes of North America and Eurasia, especially in cold seasons, which is closely associated with the negative North Atlantic Oscillation (NAO) and Arctic Oscillation (AO) and cold air propagation by the Arctic-original northerly wind anomaly into mid-latitudes. However, the warming rates of T2 and T24 are significantly different at regional and seasonal scales because T2 only samples air temperature twice daily and cannot accurately reflect land-atmosphere and incoming radiation variations in the temperature diurnal cycle. The trend has a standard deviation of 0.43 °C/decade for T2 and 0.41 °C/decade for T24, and 0.38 °C/decade for their trend difference in 5° × 5° grids. The use of T2 amplifies the regional contrasts of the warming rate, i.e., the trend underestimation in the US and overestimation at high latitudes by T2. PMID:27531421

  17. Spatiotemporal Divergence of the Warming Hiatus over Land Based on Different Definitions of Mean Temperature

    NASA Astrophysics Data System (ADS)

    Zhou, Chunlüe; Wang, Kaicun

    2016-08-01

    Existing studies of the recent warming hiatus over land are primarily based on the average of daily minimum and maximum temperatures (T2). This study compared regional warming rates of mean temperature based on T2 and T24 calculated from hourly observations available from 1998 to 2013. Both T2 and T24 show that the warming hiatus over land is apparent in the mid-latitudes of North America and Eurasia, especially in cold seasons, which is closely associated with the negative North Atlantic Oscillation (NAO) and Arctic Oscillation (AO) and cold air propagation by the Arctic-original northerly wind anomaly into mid-latitudes. However, the warming rates of T2 and T24 are significantly different at regional and seasonal scales because T2 only samples air temperature twice daily and cannot accurately reflect land-atmosphere and incoming radiation variations in the temperature diurnal cycle. The trend has a standard deviation of 0.43 °C/decade for T2 and 0.41 °C/decade for T24, and 0.38 °C/decade for their trend difference in 5° × 5° grids. The use of T2 amplifies the regional contrasts of the warming rate, i.e., the trend underestimation in the US and overestimation at high latitudes by T2.

  18. A Study of Contact Binaries with Large Temperature Differences between Components

    NASA Astrophysics Data System (ADS)

    Siwak, M.; Zola, S.; Koziel-Wierzbowska, D.

    2010-12-01

    We present an extensive analysis of new light and radial velocity (RV) curves, as well as high quality broadening function (BF) profiles of twelve binary systems for which a contact configuration with large temperature differences between components has been reported in the literature. We find that six systems (V1010 Oph, WZ Cyg, VV Cet, DO Cas, FS Lup, V747 Cen) have near contact configurations. For the remaining systems (CX Vir, FT Lup, BV Eri, FO Hya, CN And, BX And), our solutions of the new observations once again converge in a contact configuration with large temperature differences between the components. However, the bright regions discovered in the BFs for V747 Cen, CX Vir, FT Lup, BV Eri, FO Hya, and CN And, and further attributed to hot spots, shed new light on the physical processes taking place between the components and imply the possibility that the contact configurations obtained from light and RV curve modeling are a spurious result.

  19. Influence of Light Intensity at Different Temperatures on Rate of Respiration of Douglas-Fir Seedlings

    PubMed Central

    Brix, Holger

    1968-01-01

    The rate of photorespiration of Douglas-fir seedlings was measured under different light intensities by: (1) extrapolating the curve for CO2 uptake in relation to atmospheric CO2 content to zero CO2 content, and (2) measuring CO2 evolution of the plants into a CO2-free airstream. Different results, obtained from these techniques, were believed to be caused by a severe restriction of the photosynthetic activity when the latter was used. With the first method, CO2 evolution was lower than the dark respiration rate at low light intensity. For all temperatures studied (6°, 20°, 28°) a further increase in light intensity raised the CO2 evolution above dark respiration before it leveled off. The rate of CO2 evolution was stimulated by increase in temperature at all light intensities. With the CO2-free air method, CO2 evolution in the light was less than dark respiration at all light intensities. PMID:16656775

  20. Releasing H2 molecules with a partial pressure difference without the use of temperature

    NASA Astrophysics Data System (ADS)

    Lee, Hoonkyung; Huang, Bing; Duan, Wenhui; Ihm, Jisoon

    2010-08-01

    Using the pseudopotential density-functional method as well as equilibrium thermodynamic functions, we explore the process of releasing H2 molecules adsorbed on a transition-metal atom caused by the hydrogen-ammonia partial pressure difference. The H2 molecules bind to a transition-metal atom at H2 pressure- NH3 pressure-temperature 50atm-10-9atm-25°C , and they are released at 3atm-10-6atm-25°C . This process involves the same mechanism responsible for carbon monoxide poisoning of hemoglobin with the O2-CO partial pressure difference. We show that our findings can be applicable to an approach to induce hydrogen desorption on nanostructured hydrogen-storage materials without the need for increasing temperature.

  1. Avoiding hypothermia in neonatal pigs: effect of duration of floor heating at different room temperatures.

    PubMed

    Pedersen, L J; Malmkvist, J; Kammersgaard, T; Jørgensen, E

    2013-01-01

    The effect of different farrowing room temperatures (15, 20, or 25°C), combined with floor heating (FH) at the birth site, on the postnatal rectal temperature of pigs, use of creep area, and latency to first colostrum uptake was investigated with 61 litters born by loose-housed sows. Pig rectal temperature was measured at birth, as well as at 0.25, 0.5, 1, 1.5, 2, 3, 4, 12, 24, and 48 h after birth. The drop in rectal temperature from birth to 0.5 h postpartum was less (P<0.05) at room temperature of 25°C compared with 20 and 15°C. Minimum rectal temperature was less (P<0.001) at 15°C than either 20 or 25°C, and the time it took for rectal temperature to increase above 37°C was longer (P<0.05) when room temperature was 15°C than 20 and 25°C. Rectal temperatures at 24 (P<0.001) and 48 h (P<0.05) postpartum were also lower at room temperature of 15°C than 20 and 25°C. Duration of FH (12 or 48 h) did not influence (P>0.28) the rectal temperature at 24 or 48 h after birth. More pigs used the creep area 12 to 60 h after birth of the first pig at a room temperature of 15°C with 12 h FH compared with all other treatments. During the latter part of this period, more pigs stayed in the creep area also at 20°C with 12 h FH. After 60 h, more pigs (P<0.01) used the creep area at low compared with high room temperatures (15°C>20°C>25°C). Odds ratio of pigs dying before they had suckled was 6.8 times greater (P=0.03) at 15 than 25°C (95% CI of 1.3 to 35.5), whereas the odds ratio of dying during the first 7 d was 1.6 greater (P=0.05) for 48 vs. 12 h of FH (95% CI of 1.0 to 2.57), mainly due to more pigs being crushed. In conclusion, FH for 48 h was no more favorable than 12 h for pigs because the risk of hypothermia was equal in the 2 treatments, and the risk of dying increased with the longer FH duration. Increasing the room temperature to 25°C reduced hypothermia and the risk of pigs dying before colostrum intake.

  2. The circadian body temperature rhythm of Djungarian Hamsters (Phodopus sungorus) revealing different circadian phenotypes.

    PubMed

    Schöttner, Konrad; Waterhouse, Jim; Weinert, Dietmar

    2011-06-01

    Djungarian hamsters (Phodopus sungorus) of our breeding stock show three rhythmic phenotypes: wild type (WT) animals which start their activity shortly after "lights-off" and are active until "lights-on"; delayed activity onset (DAO) hamsters whose activity onset is delayed after "lights-off" but activity offset coincides with "lights-on"; and arrhythmic hamsters (AR) that are episodically active throughout the 24-h day. The main aim of the present study was to investigate whether the observed phenotypic differences are caused by an altered output from the suprachiasmatic nuclei (SCN). As a marker of the circadian clock, the body temperature rhythm purified from masking effects due to motor activity was used. Hamsters were kept singly under standardized laboratory conditions (L:D=14:10h, T: 22°C±2°C, food and water ad libitum). Body temperature and motor activity were monitored by means of implanted G2-E-Mitters and the VitalView(®) System (MiniMitter). Each phenotype showed distinctive rhythms of overt activity and body temperature, these two rhythms being very similar for each phenotype. Correcting body temperatures for the effects of activity produced purified temperature rhythms which retained profiles that were distinctive for the phenotype. These results show that the body temperature rhythm is not simply a consequence of the activity pattern but is caused by the endogenous circadian system. The purification method also allowed estimation of thermoregulatory efficiency using the gradients as a measure for the sensitivity of body temperature to activity changes. In WT and DAO hamsters, the gradients were low during activity period and showed two peaks. The first one occurred after "lights-on", the second one preceded the activity onset. In AR hamsters, the gradients did not reveal circadian changes. The results provide good evidence that the different phenotypes result from differences in the circadian clock. In AR hamsters, the SCN do not produce an

  3. Mass-controlled capillary viscometer for a Newtonian liquid: viscosity of water at different temperatures.

    PubMed

    Digilov, Rafael M; Reiner, M

    2007-03-01

    The operation principle of the mass-controlled capillary viscometer is presented for a Newtonian liquid. The derived equation for the temporal changes of the mass in a liquid column draining under gravity through a discharge capillary tube accounts self-consistently for the inertial convective term associated with the acceleration effect. The viscosity of water measured at different temperatures using the new approach is in good agreement with literature data.

  4. The ratios of partition functions at different temperatures - Sensitivity to potential energy shape II

    NASA Astrophysics Data System (ADS)

    Buchowiecki, Marcin

    2016-05-01

    The ratios of partition functions at different temperatures are calculated and its dependence on potential energy shape is analyzed. The role of anharmonicity and non-rigidity of rotations is discussed in the context of the angular frequency and the shape of potential energy curve. A role of inflection point of potential energy curve for the quality of rigid rotor harmonic oscillator and rigid rotor Morse oscillator is elucidated.

  5. Perselectivity of porous cellulose nitrate membranes in evapomeation with temperature difference

    SciTech Connect

    Uragami, T.; Komatsu, R.; Miyata, T.

    1995-12-01

    Ethanol-permselectivity from aqueous ethanol solutions through porous cellulose nitrate membranes was investigated by evaporation with temperature difference under various conditions. On the other hand, same experiments using porous cellulose acetate were carried out. From these results of porous cellulose nitrate and cellulose acetate membranes, mechanism of permeation and separation for ethanol-permselectivity through cellulose nitrate membranes is discussed from viewpoints of physical and chemical structures of porous cellulose ester membranes.

  6. Influence of temperature difference calculation method on the evaluation of Rankine cycle performance

    NASA Astrophysics Data System (ADS)

    Morisaki, Takafumi.; Ikegami, Yasuyuki.

    2014-02-01

    In the new century, energy and environmental problems are becoming more critical, and the development of natural energy is desired. Low-grade Thermal Energy Conversion (LTEC) is refocused as one of the renewable energy methods. The usefulness of LTEC is expected using hot springs and waste heat. In the case of the Rankine cycle using ammonia as the working fluid, the thermal properties of the working fluid changes in the evaporator. The traditional evaluation method of heat exchanger performance is the LMTD (Logarithmic Mean Temperature Difference) method. On the other hand, the GMTD (Generalized Mean Temperature Difference) method allows the variation of thermal properties in the heat exchanger. The aim of this study is to compare the two methods for the calculation of temperature differences and the corresponding influence on the total performance of the Rankine cycle that is operated using ammonia as a working fluid. As a result, the thermal efficiency of the Rankine cycle is greater than that of the LMTD method. Moreover, the computable range of the GMTD calculation method is less than that of the LMTD calculation method.

  7. Water structure-forming capabilities are temperature shifted for different models.

    PubMed

    Shevchuk, Roman; Prada-Gracia, Diego; Rao, Francesco

    2012-06-28

    A large number of water models exist for molecular simulations. They differ in the ability to reproduce specific features of real water instead of others, like the correct temperature for the density maximum or the diffusion coefficient. Past analysis mostly concentrated on ensemble quantities, while few data were reported on the different microscopic behavior. Here, we compare seven widely used classical water models (SPC, SPC/E, TIP3P, TIP4P, TIP4P-Ew, TIP4P/2005, and TIP5P) in terms of their local structure-forming capabilities through hydrogen bonds for temperatures ranging from 210 to 350 K by the introduction of a set of order parameters taking into account the configuration of up to the second solvation shell. We found that all models share the same structural pattern up to a temperature shift. When this shift is applied, all models overlap onto a master curve. Interestingly, increased stabilization of fully coordinated structures extending to at least two solvation shells is found for models that are able to reproduce the correct position of the density maximum. Our results provide a self-consistent atomic-level structural comparison protocol, which can be of help in elucidating the influence of different water models on protein structure and dynamics.

  8. Relationships between the addition rates of cellulase or glucose and silage fermentation at different temperatures.

    PubMed

    Zhang, Jian-Guo; Kawamoto, Hidenori; Cai, Yi-Min

    2010-06-01

    The influence of the application rates of cellulase preparation and glucose on silage fermentation at different temperatures was studied with the straw of naked barley (Hordeum vulgare L. emand Lam) and guineagrass (Panicum maximum Jacq.). Addition rate of cellulase and glucose, temperature and their interaction had significant effects on pH value, lactic acid content, butyric acid content and propionic acid content of naked barley straw silage and significant effects on all the parameters of guineagrass silage (P < 0.01). Temperature and interaction had significant effect on acetic acid content (P < 0.05) and no significant effect on NH(3)-N content of naked barley straw silage (P > 0.05). Under all the temperatures, the pH values of barley straw and guineagrass silages were reduced by cellulase and glucose addition even at the lowest rate (P < 0.05), compared with their corresponding control. Lactic acid contents of silages were the highest within the same temperature and same additive when glucose and cellulase were added at the highest rates, whereas the effect of cellulase and glucose addition on butyric acid production varied with their application rates and silage storage temperature. The addition rate of restricting butyric acid fermentation was lower at 20 degrees C than that at 30 degrees C, and it was the lowest at 40 degrees C where cellulase and glucose addition restricted butyric acid fermentation even at 0.1 g/kg and 10 g/kg, respectively, when compared to the control. While the addition rate was lower than the above level, cellulase and glucose addition also promoted butyric acid fermentation.

  9. Effect of Different Cooling Regimes on the Mechanical Properties of Cementitious Composites Subjected to High Temperatures

    PubMed Central

    Yu, Jiangtao; Weng, Wenfang; Yu, Kequan

    2014-01-01

    The influence of different cooling regimes (quenching in water and cooling in air) on the residual mechanical properties of engineered cementitious composite (ECC) subjected to high temperature up to 800°C was discussed in this paper. The ECC specimens are exposed to 100, 200, 400, 600, and 800°C with the unheated specimens for reference. Different cooling regimens had a significant influence on the mechanical properties of postfire ECC specimens. The microstructural characterization was examined before and after exposure to fire deterioration by using scanning electron microscopy (SEM). Results from the microtest well explained the mechanical properties variation of postfire specimens. PMID:25161392

  10. A comparison of three different types of temperature measurement in HITU fields

    NASA Astrophysics Data System (ADS)

    Haller, J.; Jenderka, K.-V.; Seifert, F.; Klepsch, T.; Martin, E.; Shaw, A.; Durando, G.; Guglielmone, C.; Girard, F.

    2012-10-01

    The spatial and temporal distribution of the temperature elevation caused by high-intensity therapeutic ultrasound (HITU) in a tissue-mimicking material (TMM) has been determined with magnetic resonance (MR) thermometry, infrared (IR) thermometry and a thermal test object with an integrated thin-film thermocouple at three different National Metrological Institutes (PTB/Germany, NPL/UK, INRIM/Italy). Results obtained from the different types of measurement are compared and some general aspects of the methods are discussed, particularly with regard to their suitability for the in vitro characterization of transducers for treatment planning.

  11. Determination of regional brain temperature using proton magnetic resonance spectroscopy to assess brain-body temperature differences in healthy human subjects.

    PubMed

    Childs, Charmaine; Hiltunen, Yrjö; Vidyasagar, Rishma; Kauppinen, Risto A

    2007-01-01

    Proton magnetic resonance spectroscopy ((1)H MRS) was used to determine brain temperature in healthy volunteers. Partially water-suppressed (1)H MRS data sets were acquired at 3T from four different gray matter (GM)/white matter (WM) volumes. Brain temperatures were determined from the chemical-shift difference between the CH(3) of N-acetyl aspartate (NAA) at 2.01 ppm and water. Brain temperatures in (1)H MRS voxels of 2 x 2 x 2 cm(3) showed no substantial heterogeneity. The volume-averaged temperature from single-voxel spectroscopy was compared with body temperatures obtained from the oral cavity, tympanum, and temporal artery regions. The mean brain parenchyma temperature was 0.5 degrees C cooler than readings obtained from three extra-brain sites (P < 0.01). (1)H MRS imaging (MRSI) data were acquired from a slice encompassing the single-voxel volumes to assess the ability of spectroscopic imaging to determine regional brain temperature within the imaging slice. Brain temperature away from the center of the brain determined by MRSI differed from that obtained by single-voxel MRS in the same brain region, possibly due to a poor line width (LW) in MRSI. The data are discussed in the light of proposed brain-body temperature gradients and the use of (1)H MRSI to monitor brain temperature in pathologies, such as brain trauma.

  12. Charge recombination reactions in photosystem II. 2. Transient absorbance difference spectra and their temperature dependence.

    PubMed

    Hillmann, B; Brettel, K; van Mieghem, F; Kamlowski, A; Rutherford, A W; Schlodder, E

    1995-04-11

    Absorbance difference spectra of the transient states in photosystem II (PS II) have been examined in the Qv absorption region between 660 and 700 nm. The P680+Pheo-/P680Pheo, 3P680/P680, and P680+QA-/P680QA spectra were measured in O2-evolving PS II core complexes from Synechococcus and PS II-enriched membrane fragments from spinach. The low-temperature absorbance difference spectra vary only slightly between both PS II preparations. The 3P680/P680 spectrum is characterized by a bleaching at 685 nm at 25 K and indicates weak exciton coupling with neighboring pigment(s). We conclude that P680 absorbs at 685 nm in more intact PS II preparations at cryogenic temperature. The difference spectra of the radical pairs are strongly temperature dependent. At low temperature the P680+QA-/P680QA- spectrum exhibits the strongest bleaching at 675 nm whereas the P680+Phe-/P680Pheo spectra show two distinct bleaching bands at 674 and 684 nm. It is suggested that an electrochronic red shift resulting in a bleaching at 675 nm and an absorbance increase at about 682 nm dominates the spectral features of the charge-separated states. On the basis of the present results and those in the literature, we conclude that the interactions between the pigments and especially the organization of the primary donor must be quite different in PS II compared to bacterial reaction centers, although the basic structural arrangement of the pigments might be similar. Spectral data obtained with samples in the presence of singly and doubly reduced QA indicate that the primary photochemistry in PS II is not strongly influenced by the redox state of QA at low temperature and confirm the results of the accompanying paper [Van Mieghem, F. J. E., Brettel, K., Hillmann, B., Kamlowski, A., Rutherford, A. W., & Schlodder, E. (1995) Biochemistry 34, 4798-4813]. The spectra of the primary radical pair and the reaction center triplet obtained with more intact PS II preparations differ widely from those of D1/D2

  13. A comparison of temperature and precipitation responses to different Earth radiation management geoengineering schemes

    NASA Astrophysics Data System (ADS)

    Crook, J. A.; Jackson, L. S.; Osprey, S. M.; Forster, P. M.

    2015-09-01

    Earth radiation management has been suggested as a way to rapidly counteract global warming in the face of a lack of mitigation efforts, buying time and avoiding potentially catastrophic warming. We compare six different radiation management schemes that use surface, troposphere, and stratosphere interventions in a single climate model in which we projected future climate from 2020 to 2099 based on RCP4.5. We analyze the surface air temperature responses to determine how effective the schemes are at returning temperature to its 1986-2005 climatology and analyze precipitation responses to compare side effects. We find crop albedo enhancement is largely ineffective at returning temperature to its 1986-2005 climatology. Desert albedo enhancement causes excessive cooling in the deserts and severe shifts in tropical precipitation. Ocean albedo enhancement, sea-spray geoengineering, cirrus cloud thinning, and stratospheric SO2 injection have the potential to cool more uniformly, but cirrus cloud thinning may not be able to cool by much more than 1 K globally. We find that of the schemes potentially able to return surface air temperature to 1986-2005 climatology under future greenhouse gas warming, none has significantly less severe precipitation side effects than other schemes. Despite different forcing patterns, ocean albedo enhancement, sea-spray geoengineering, cirrus cloud thinning, and stratospheric SO2 injection all result in large scale tropical precipitation responses caused by Hadley cell changes and land precipitation changes largely driven by thermodynamic changes. Widespread regional scale changes in precipitation over land are significantly different from the 1986-2005 climatology and would likely necessitate significant adaptation despite geoengineering.

  14. Effects of elevated temperatures on different restorative materials: An aid to forensic identification processes

    PubMed Central

    Pol, Chetan A.; Ghige, Suvarna K.; Gosavi, Suchitra R.; Hazarey, Vinay K.

    2015-01-01

    Background: Heat-induced alterations to dental and restorative materials can be of great interest to forensic dentistry. Knowing the specific optical behavior of dental materials can be of high importance as recognition of changes induced by high temperatures can lead to the determination of material which was used in a dental restoration, facilitating identification of burned human remains. Aim: To observe the effects of predetermined temperatures (200°C–400°C–600°C–800°C–1000°C) on unrestored teeth and different restorative materials macroscopically and then examine them under a stereomicroscope for the purpose of identification. Materials and Methods: The study was conducted on 375 extracted teeth which were divided into five groups of 75 teeth each as follows: group 1- unrestored teeth, group 2- teeth restored with all-ceramic crowns, Group 3- with class I silver amalgam filling, group 4- with class I composite restoration, and group 5- with class I glass ionomer cement restoration. Results: Unrestored and restored teeth display a series of specific macroscopic & stereomicroscopic structural changes for each range of temperature. Conclusion: Dental tissues and restorative materials undergo a series of changes which correlate well with the various temperatures to which they were exposed. These changes are a consequence of the nature of the materials and their physicochemical characteristics. PMID:26005305

  15. Temperature-induced gene expression associated with different thermal reaction norms for growth rate.

    PubMed

    Ellers, Jacintha; Mariën, Janine; Driessen, Gerard; van Straalen, Nico M

    2008-03-15

    Although nearly all organisms are subject to fluctuating temperature regimes in their natural habitat, little is known about the genetics underlying the response to thermal conditions, and even less about the genetic differences that cause individual variation in thermal response. Here, we aim to elucidate possible pathways involved in temperature-induced phenotypic plasticity of growth rate. Our model organism is the collembolan Orchesella cincta that occurs in a wide variety of habitats and is known to be adapted to local thermal conditions. Because sequence information is lacking in O. cincta, we constructed cDNA libraries enriched for temperature-responsive genes using suppression subtractive hybridization. We compared gene expression of O. cincta with steep thermal reaction norms (high plasticity) to those with flat thermal reaction norms (low plasticity) for juvenile growth after exposure to a temperature switch composed of a cooling or a warming treatment. Using suppression subtractive hybridization, we found differential expression of ten nuclear genes, including several genes involved in energy metabolism, such as pantothenate kinase and carbonic anhydrase. In addition, seven mitochondrial genes were found in the cloned subtracted library, but further analysis showed this was caused by allelic variation in mitochondrial genes in our founder population, and that a specific haplotype was associated with high thermal responsiveness. Future work will focus on candidate genes from pathways such as the oxidative phosphorylation and biosynthesis of coenzyme A which are possibly involved in thermal responsiveness of juvenile growth rate.

  16. An improved method for correction of air temperature measured using different radiation shields

    NASA Astrophysics Data System (ADS)

    Cheng, Xinghong; Su, Debin; Li, Deping; Chen, Lu; Xu, Wenjing; Yang, Meilin; Li, Yongcheng; Yue, Zhizhong; Wang, Zijing

    2014-11-01

    The variation of air temperature measurement errors using two different radiation shields (DTR502B Vaisala, Finland, and HYTFZ01, Huayun Tongda Satcom, China) was studied. Datasets were collected in the field at the Daxing weather station in Beijing from June 2011 to May 2012. Most air temperature values obtained with these two commonly used radiation shields were lower than the reference records obtained with the new Fiber Reinforced Polymers (FRP) Stevenson screen. In most cases, the air temperature errors when using the two devices were smaller on overcast and rainy days than on sunny days; and smaller when using the imported rather than the Chinese shield. The measured errors changed sharply at sunrise and sunset, and reached maxima at noon. Their diurnal variation characteristics were, naturally, related to changes in solar radiation. The relationships between the record errors, global radiation, and wind speed were nonlinear. An improved correction method was proposed based on the approach described by Nakamura and Mahrt (2005) (NM05), in which the impact of the solar zenith angle (SZA) on the temperature error is considered and extreme errors due to changes in SZA can be corrected effectively. Measurement errors were reduced significantly after correction by either method for both shields. The error reduction rate using the improved correction method for the Chinese and imported shields were 3.3% and 40.4% higher than those using the NM05 method, respectively.

  17. Long-term global temperature variations under the influence of different cosmophysical factors

    NASA Astrophysics Data System (ADS)

    Biktash, Lilia

    2016-07-01

    We have analyzed different cosmophysical factors which have effect on long-term global temperature variations during solar cycles 20-24. A detailed analysis of total solar irradiance (TSI), the spectral solar ultraviolet emission (UV), space weather and cosmic rays (CRs) have effects on the atmosphere processes. We have shown that increasing of global temperature is likely affected by TSI and UV during solar maxima. During the descending phases of these solar cycles the interplanetary magnetic field and long-lasting solar wind high speed streams occurred frequently and were the primary contributors to minimize of CRs effect on the Earth's atmosphere. In this case global temperature is increased extra as result of increase in the atmosphere's transparency. We show that there are a few effective physical mechanisms of the action of solar activity and space weather on the global temperature. TSI and CRs play essential role in climate change and main part of climate variations can be explained by the mechanism of action TSI and CRs modulated by the solar activity on the state of lower atmosphere and meteorological parameters.

  18. Pore distribution and material properties of bone cement cured at different temperatures.

    PubMed

    Pelletier, Matthew H; Lau, Abe C B; Smitham, Peter J; Nielsen, Gary; Walsh, William R

    2010-03-01

    Implant heating has been advocated as a means to alter the porosity of the bone cement/implant interface; however, little is known about the influence on cement properties. This study investigates the mechanical properties and pore distribution of 10 commercially available cements cured in molds at 20, 37, 40 and 50 degrees Celsius. Although each cement reacted differently to the curing environments, the most prevalent trend was increased mechanical properties when cured at 50 degrees Celsius vs. room temperature. Pores were shown to gather near the surface of cooler molds and near the center in warmer molds for all cement brands. Pore size was also influenced. Small pores were more often present in cements cured at cooler temperatures, with higher-temperature molds producing more large pores. The mechanical properties of all cements were above the minimum regulatory standards. This work shows the influence of curing temperature on cement properties and porosity characteristics, and supports the practice of heating cemented implants to influence interfacial porosity.

  19. CREST modelling of PBX 9502 corner turning experiments at different initial temperatures

    NASA Astrophysics Data System (ADS)

    Whitworth, N. J.

    2014-05-01

    Corner turning is an important problem in regard to detonation wave propagation in TATB-based explosives. Experimentally, a sudden change in the direction of the propagating wave, such as turning a sharp corner, can result in dead-zones being left behind in the corner turn region, with the observed behaviour being particularly sensitive to the initial temperature of the explosive. In this paper, the entropy-dependent CREST reactive burn model is used to simulate corner turning experiments on the TATB-based explosive PBX 9502. Calculated results of double cylinder tests at three different initial temperatures (-54°C, ~23°C, and 75°C), and a "hockey puck" experiment at ambient temperature, are compared to the corresponding test measurements. The results show that the model is able to: (i) calculate persistent dead-zones in PBX 9502 without recourse to any shock desensitisation treatment, and (ii) predict changes in corner turning behaviour with initial temperature using one set of coefficients.

  20. CREST Modelling of PBX 9502 Corner Turning Experiments at Different Initial Temperatures

    NASA Astrophysics Data System (ADS)

    Whitworth, Nicholas

    2013-06-01

    Corner turning is an important problem in regard to detonation wave propagation in TATB-based explosives. Experimentally, a sudden change in direction of the propagating wave, such as turning a sharp corner, can result in dead-zones being left behind in the corner turn region, with the observed behaviour being particularly sensitive to the initial temperature of the explosive. In this paper, the entropy-dependent CREST reactive burn model is used to simulate corner turning experiments on the TATB-based explosive PBX 9502. Calculated results of double cylinder tests at three different initial temperatures (-54°C, 25°C, and 75°C), and a ``hockey puck'' experiment at ambient temperature, are compared to the corresponding test measurements. The results show that the model is able to: (i) calculate persistent dead-zones in PBX 9502 without recourse to any shock desensitisation treatment, and (ii) predict changes in corner turning behaviour with initial temperature using one set of coefficients.

  1. Thermal decay analysis of fiber Bragg gratings at different temperature annealing rates using demarcation energy approximation

    NASA Astrophysics Data System (ADS)

    Gunawardena, Dinusha Serandi; Lai, Man-Hong; Lim, Kok-Sing; Ahmad, Harith

    2017-03-01

    In this study the thermal degradation of gratings inscribed in three types of fiber namely, PS 1250/1500, SM 1500 and zero water peak single mode fiber is demonstrated. A comparative investigation is carried out on the aging characteristics of the gratings at three different temperature ramping rates of 3 °C/min, 6 °C/min and 9 °C/min. During the thermal annealing treatment, a significant enhancement in the grating reflectivity is observed for PS 1250/1500 fiber from ∼1.2 eV until 1.4 eV which indicates a thermal induced reversible effect. Higher temperature ramping rates lead to a higher regeneration temperature. In addition, the investigation also reflects that regardless of the temperature ramping rate the thermal decay behavior of a specific fiber can be successfully characterized when represented in a demarcation energy domain. Moreover, this technique can be accommodated when predicting the thermal decay characteristics of a specific fiber.

  2. Comparison of different methods of estimating the mean radiant temperature in outdoor thermal comfort studies.

    PubMed

    Krüger, E L; Minella, F O; Matzarakis, A

    2014-10-01

    Correlations between outdoor thermal indices and the calculated or measured mean radiant temperature T(mrt) are in general of high importance because of the combined effect on human energy balance in outdoor spaces. The most accurate way to determine T(mrt) is by means of integral radiation measurements, i.e. measuring the short- and long-wave radiation from six directions using pyranometers and pyrgeometers, an expensive and not always an easily available procedure. Some studies use globe thermometers combined with air temperature and wind speed sensors. An alternative way to determine T(mrt) is based on output from the RayMan model from measured data of incoming global radiation and morphological features of the monitoring site in particular sky view factor (SVF) data. The purpose of this paper is to compare different methods to assess the mean radiant temperature T(mrt) in terms of differences to a reference condition (T(mrt) calculated from field measurements) and to resulting outdoor comfort levels expressed as PET and UTCI values. The T(mrt) obtained from field measurements is a combination of air temperature, wind speed and globe temperature data according to the forced ventilation formula of ISO 7726 for data collected in Glasgow, UK. Four different methods were used in the RayMan model for T(mrt) calculations: input data consisting exclusively of data measured at urban sites; urban data excluding solar radiation, estimated SVF data and solar radiation data measured at a rural site; urban data excluding solar radiation with SVF data for each site; urban data excluding solar radiation and including solar radiation at the rural site taking no account of SVF information. Results show that all methods overestimate T(mrt) when compared to ISO calculations. Correlations were found to be significant for the first method and lower for the other three. Results in terms of comfort (PET, UTCI) suggest that reasonable estimates could be made based on global radiation

  3. Prediction of the thermal imaging minimum resolvable (circle) temperature difference with neural network application.

    PubMed

    Fang, Yi-Chin; Wu, Bo-Wen

    2008-12-01

    Thermal imaging is an important technology in both national defense and the private sector. An advantage of thermal imaging is its ability to be deployed while fully engaged in duties, not limited by weather or the brightness of indoor or outdoor conditions. However, in an outdoor environment, many factors, including atmospheric decay, target shape, great distance, fog, temperature out of range and diffraction limits can lead to bad image formation, which directly affects the accuracy of object recognition. The visual characteristics of the human eye mean that it has a much better capacity for picture recognition under normal conditions than artificial intelligence does. However, conditions of interference significantly reduce this capacity for picture recognition for instance, fatigue impairs human eyesight. Hence, psychological and physiological factors can affect the result when the human eye is adopted to measure MRTD (minimum resolvable temperature difference) and MRCTD (minimum resolvable circle temperature difference). This study explores thermal imaging recognition, and presents a method for effectively choosing the characteristic values and processing the images fully. Neural network technology is successfully applied to recognize thermal imaging and predict MRTD and MRCTD (Appendix A), exceeding thermal imaging recognition under fatigue and the limits of the human eye.

  4. Monoethanol amine modified zeolite 13X for CO{sub 2} adsorption at different temperatures

    SciTech Connect

    P.D. Jadhav; R.V. Chatti; R.B. Biniwale; N.K. Labhsetwar; S. Devotta; S.S. Rayalu . s_rayalu@neeri.res.in

    2007-12-15

    Zeolite 13X has been modified with monoethanol amine (MEA). MEA loadings of 0.5-25 wt % have been achieved using the impregnation method in different solvents. The mode of incorporation based on methanol with stirring at room temperature appears to be the most feasible. The adsorbent has been characterized for crystallinity, surface area, pore volume, and pore size. The thermal stability of the adsorbent is studied using a thermal analyzer. The CO{sub 2} adsorption capacity of adsorbents is evaluated using the breakthrough adsorption method with a packed column on a 10 g scale. The adsorption capacities of adsorbents are estimated in the temperature range 30-120{sup o}C. The adsorbents show improvement in CO{sub 2} adsorption capacity over the unmodified zeolite by a factor of ca. 1.6 at 30{sup o}C, whereas at 120{sup o}C the efficiency improved by a factor of 3.5. For adsorption at these temperatures, different MEA loading levels were found to be suitable as per the governing adsorption phenomena, that is, physical or chemical. The adsorbent is also studied for CO{sub 2} selectivity over N{sub 2} at 75{sup o}C. The MEA-modified adsorbent shows better CO{sub 2} selectivity, which was improved further in the presence of moisture. 25 refs., 6 figs., 3t abs.

  5. Antigenicity and viability of Anisakis larvae infesting hake heated at different time-temperature conditions.

    PubMed

    Vidacek, Sanja; de las Heras, Cristina; Solas, Maria Teresa; Mendizábal, Angel; Rodriguez-Mahillo, Ana I; Tejada, Margarita

    2010-01-01

    Heat treatments (40 to 94 degrees Celsius, 30 s to 60 min) were applied to different batches of Anisakis simplex L3 larvae isolated from hake ovaries and viscera to study the effect of heat on the viability of the larvae measured as mobility, emission of fluorescence under UV light, and changes in color after staining with specific dyes, and on A. simplex antigenic proteins. The aim was to determine the lowest time-temperature conditions needed to kill the larvae to avoid anisakiasis in consumers, and to evaluate whether high temperature modifies the antigenicity of A. simplex extracts. Heating at 60 degrees Celsius for 10 min (recommended by some authors) was considered unsafe, as differences in viability between batches were found, with some larvae presenting spontaneous movements in one batch. At higher temperatures (> or = 70 degrees Celsius for > or = 1 min), no movement of the larvae was observed. Antigenic protein Ani s 4 and A. simplex crude antigens were detected in the larvae heated at 94 + or - 1 degrees Celsius for 3 min. This indicates that allergic symptoms could be provoked in previously sensitized consumers, even if the larvae were killed by heat treatment.

  6. Formation of brominated pollutants during the pyrolysis and combustion of tetrabromobisphenol A at different temperatures.

    PubMed

    Ortuño, Nuria; Moltó, Julia; Conesa, Juan A; Font, Rafael

    2014-08-01

    Tetrabromobisphenol A (TBBPA) is the most widely used brominated flame retardant worldwide. A detailed examination of the degradation products emitted during thermal decomposition of TBBPA is presented in the study. Runs were performed in a laboratory furnace at different temperatures (650 and 800 °C) and in different atmospheres (nitrogen and air). More than one hundred semivolatile compounds have been identified by GC/MS, with special interest in brominated ones. Presence of HBr and brominated light hydrocarbons increased with temperature and in the presence of oxygen. Maximum formation of PAHs is observed at pyrolytic condition at the higher temperature. High levels of 2,4-, 2,6- and 2,4,6- bromophenols were found. The levels of polybrominated dibenzo-p-dioxins and furans have been detected in the ppm range. The most abundant isomers are 2,4,6,8-TeBDF in pyrolysis and 1,2,3,7,8-PeBDF in combustion. These results should be considered in the assessment of thermal treatment of materials containing brominated flame retardants.

  7. Size distribution of carbon layer planes in biochar from different plant type of feedstock with different heating temperatures.

    PubMed

    Lu, Guan-Yang; Ikeya, Kosuke; Watanabe, Akira

    2016-11-01

    Biochar application to soil is a strategy to decelerate the increase in the atmospheric carbon concentration. The composition of condensed aromatic clusters appears to be an important determinant of the degradation rate of char in soil. The objective of the present study was to determine the size distribution of carbon layer planes in biochars produced from different types of feedstock (a broadleaf and a coniferous tree and two herbs) using different heating treatment temperatures (HTT; 400 °C-800 °C) using X-ray diffraction 11 band profile analysis. (13)C nuclear magnetic resonance with the phase-adjusted spinning side bands of the chars indicated different spectral features depending on the HTT and similar carbon composition among the plant types at each HTT. Both the content and composition of carbon layer planes in biochar produced using the same HTT were also similar among the plant types. The carbon layer plane size in the 400 °C and 600 °C chars was distributed from 0.24 to 1.68 or 1.92 nm (corresponding to 37 or 52 rings) with the mean size of 0.79-0.92 and 0.80-1.14 nm, respectively. The carbon layer planes in the 800 °C chars ranged from 0.72-0.96 nm (7-14 rings) to 2.64-3.60 nm (91-169 rings) and the mean values were 1.47-1.89 nm. The relative carbon layer plane content in the 600 °C and 800 °C chars was typically 2 and 3 times that in the 400 °C chars. These results indicate the progression of the formation and/or the size development of graphite-like structures, suggesting that a char produced at a higher HTT would have better carbon sequestrating characteristics.

  8. Differences in SOM decomposition and temperature sensitivity among soil aggregate size classes in a temperate grasslands.

    PubMed

    Wang, Qing; Wang, Dan; Wen, Xuefa; Yu, Guirui; He, Nianpeng; Wang, Rongfu

    2015-01-01

    The principle of enzyme kinetics suggests that the temperature sensitivity (Q10) of soil organic matter (SOM) decomposition is inversely related to organic carbon (C) quality, i.e., the C quality-temperature (CQT) hypothesis. We tested this hypothesis by performing laboratory incubation experiments with bulk soil, macroaggregates (MA, 250-2000 μm), microaggregates (MI, 53-250 μm), and mineral fractions (MF, <53 μm) collected from an Inner Mongolian temperate grassland. The results showed that temperature and aggregate size significantly affected on SOM decomposition, with notable interactive effects (P<0.0001). For 2 weeks, the decomposition rates of bulk soil and soil aggregates increased with increasing incubation temperature in the following order: MA>MF>bulk soil >MI(P <0.05). The Q10 values were highest for MA, followed (in decreasing order) by bulk soil, MF, and MI. Similarly, the activation energies (Ea) for MA, bulk soil, MF, and MI were 48.47, 33.26, 27.01, and 23.18 KJ mol-1, respectively. The observed significant negative correlations between Q10 and C quality index in bulk soil and soil aggregates (P<0.05) suggested that the CQT hypothesis is applicable to soil aggregates. Cumulative C emission differed significantly among aggregate size classes (P <0.0001), with the largest values occurring in MA (1101 μg g-1), followed by MF (976 μg g-1) and MI (879 μg g-1). These findings suggest that feedback from SOM decomposition in response to changing temperature is closely associated withsoil aggregation and highlights the complex responses of ecosystem C budgets to future warming scenarios.

  9. Tuning the hopping conductivity of WO3 films by ion bombardment at different temperatures

    NASA Astrophysics Data System (ADS)

    Heinz, B.; Merz, M.; Widmayer, P.; Ziemann, P.

    2001-10-01

    WO3 films, either prepared by sputtering or evaporation under high or ultrahigh vacuum conditions, were irradiated with He+ and Ar+ ions (energy range 300-350 keV) at ambient and low temperatures (77-100 K). The resulting ion induced changes of the optical absorption as well as of the electrical conductivity could be determined on one and the same sample, which enables the variable range hopping (VRH) model to be tested under the assumption that the density of irradiation induced color centers is proportional to the electronic density of states contributing to the hopping conductivity. It is found that the data obtained at 300 K for He+ and Ar+ bombardment can be described within the VRH model by one common conductivity versus absorption curve, even though the effectiveness per projectile of the heavier ion for coloration as well as for increasing the conductivity is much higher. This is different at low temperatures. While the ion induced coloration is practically independent of the irradiation temperature for both projectiles, the effectiveness per projectile to enhance the conductivity is interchanged. This is attributed to the additional damage produced by the heavier ion at low temperatures resulting in strongly impeded hopping processes. Consistent with the VRH model, the temperature dependence of the conductivity of ion bombarded WO3 films follow the Mott "T-1/4" law, if the ion induced conductivity is not too high. For very high ion fluences clear deviations from the VRH model are observed for the conductivity versus absorption curves accompanied by a shift of the above power laws from T-1/4 towards T-1/2.

  10. Basal and maximal metabolic rates differ in their response to rapid temperature change among avian species.

    PubMed

    Dubois, Karine; Hallot, Fanny; Vézina, François

    2016-10-01

    In birds, acclimation and acclimatization to temperature are associated with changes in basal (BMR), summit (Msum) and maximal (MMR) metabolic rates but little is known about the rate at which species adjust their phenotype to short-term temperature variations. Our aims were (1) to determine the pattern of metabolic adjustments following a rapid temperature change, (2) to determine whether performance varies at similar rates during exposure to warm or cold environments, and (3) to determine if BMR, Msum and MMR change at comparable rates during thermal acclimation. We measured these parameters in white-throated sparrows (Zonotrichia albicollis), black-capped chickadees (Poecile atricapillus), and snow buntings (Plectrophenax nivalis) after acclimation to 10 °C (day 0) and on the 4th and 8th days of acclimation to either -5 or 28 °C. Birds changed their metabolic phenotype within 8 days with patterns differing among species. Sparrows expressed the expected metabolic increases in the cold and decreases at thermoneutrality while performance in chickadees and buntings was not influenced by temperature but changed over time with inverse patterns. Our results suggest that BMR varies at comparable rates in warm and cold environments but changes faster than Msum and MMR, likely due to limitations in the rate of change in organ size and function. They also suggest that maximal metabolic capacity is lost faster in a warm environment than it is gained in a cold environment. With the expected increase in temperature stochasticity at northern latitudes, a loss of thermogenic capacity during warm winter days could, therefore, be detrimental if birds are slow to readjust their phenotype with the return of cold days.

  11. Difference analysis method for negative bias temperature instability lifetime prediction in deeply scaled pMOSFETs

    NASA Astrophysics Data System (ADS)

    Liao, Yiming; Ji, Xiaoli; Zhang, Chengxu; Huang, Xiaolin; Xu, Yue; Yan, Feng

    2017-04-01

    The fluctuation significantly affects the lifetime prediction of negative bias temperature instability (NBTI) for deeply scaled pMOSFETs. In this paper, we present a novel difference method to separate the time dependent fluctuation-related component from the NBTI quasi-static component in the threshold voltage shift. The extracted fluctuation-related component exhibits weak temperature and time dependences which is consistent with the characteristic of as-grown defect-induced trapping and detrapping while the quasi-static component presents electrical behaviors of generated-defect-induced NBTI degradation. On the basis of these results, a composite NBTI model is constructed and lifetime projection is derived for the small pMOSFETs.

  12. Studies of Water Absorption Behavior of Plant Fibers at Different Temperatures

    NASA Astrophysics Data System (ADS)

    Saikia, Dip

    2010-05-01

    Moisture absorption of natural fiber plastic composites is one major concern in their outdoor applications. The absorbed moisture has many detrimental effects on the mechanical performance of these composites. A knowledge of the moisture diffusivity, permeability, and solubility is very much essential for the application of natural fibers as an excellent reinforcement in polymers. An effort has been made to study the water absorption behavior of some natural fibers such as bowstring hemp, okra, and betel nut at different temperatures to improve the long-term performance of composites reinforced with these fibers. The gain in moisture content in the fibers due to water absorption was measured as a function of exposure time at temperatures ranging from 300 K to 340 K. The thermodynamic parameters of the sorption process, such as diffusion coefficients and corresponding activation energies, were estimated.

  13. Properties of Cement-based Composite Materials under Different Storing Environment Temperature

    NASA Astrophysics Data System (ADS)

    Weng, T. L.; Weng, S. H.; Cho, S. W.

    2017-02-01

    This study reports on the properties of cement-based composite materials (mortars) under different storing environment temperature, as determined using the accelerated chloride migration test (ACMT). Mortars with a water/cement ratio of 0.45 and five fine aggregate volume fractions (0%, 15%, 30%, 50% and 60%) under various environment temperatures (25, 40, 60 and 80°C) were evaluated according to the passage of chloride ions through the specimens using ACMT. Calculate chloride migration coefficients on the steady-state. Cement-based composite materials with 60 % fine aggregate presented a migration coefficient higher than that of other specimens, whereas mortar with 30 % fine aggregate was lower, due to the effects of dilution and tortuosity.

  14. Hawking radiation as perceived by different observers: an analytic expression for the effective-temperature function

    NASA Astrophysics Data System (ADS)

    Barbado, L. C.; Barceló, C.; Garay, L. J.

    2012-04-01

    Given a field vacuum state in a black hole spacetime, this state can be analysed in terms of how it is perceived (in terms of particle content) by different observers. This can be done by means of the effective-temperature function introduced by Barceló et al (2011 Phys. Rev. D 83 041501). In Barbado et al (2011 Class. Quantum Grav. 28 125021), this function was analysed in a case-by-case basis for a number of interesting situations. In this work, we find a general analytic expression for the effective-temperature function which, apart from the vacuum state choice, depends on the position, the local velocity and the acceleration of the specific observer. We give a clear physical interpretation of the quantities appearing in the expression, and illustrate its potentiality with a few examples.

  15. Thermal Diffusivity for III-VI Semiconductor Melts at Different Temperatures

    NASA Technical Reports Server (NTRS)

    Ban, H.; Li, C.; Lin, B.; Emoto, K.; Scripa, R. N.; Su, C.-H.; Lehoczky, S. L.

    2004-01-01

    The change of the thermal properties of semiconductor melts reflects the structural changes inside the melts, and a fundamental understanding of this structural transformation is essential for high quality semiconductor crystal growth process. This paper focused on the technical development and the measurement of thermal properties of III-VI semiconductor melts at high temperatures. Our previous work has improved the laser flash method for the specialized quartz sample cell. In this paper, we reported the results of our recent progress in further improvements of the measurement system by minimizing the free convection of the melt, adding a front IR detector, and placing the sample cell in a vacuum environment. The results for tellurium and selenium based compounds, some of which have never been reported in the literature, were obtained at different temperatures as a function of time. The data were compared with other measured thermophysical properties to shed light on the structural transformations of the melt.

  16. Investigation of temperature and aridity at different elevations of Mt. Ailao, SW China.

    PubMed

    You, Guangyong; Zhang, Yiping; Liu, Yuhong; Schaefer, Douglas; Gong, Hede; Gao, Jinbo; Lu, Zhiyun; Song, Qinghai; Zhao, Junbin; Wu, Chuansheng; Yu, Lei; Xie, Youneng

    2013-05-01

    Our current understanding is that plant species distribution in the subtropical mountain forests of Southwest China is controlled mainly by inadequate warmth. Due to abundant annual precipitation, aridity has been less considered in this context, yet rainfall here is highly seasonal, and the magnitude of drought severity at different elevations has not been examined due to limited access to higher elevations in this area.In this study, short-term micrometeorological variables were measured at 2,480 m and 2,680 m, where different forest types occur. Drought stress was evaluated by combining measurements of water evaporation demand (E p) and soil volumetric water content (VWC). The results showed that: (1) mean temperature decreased 1 °C from 2,480 m to 2,680 m and the minimum temperature at 2,680 m was above freezing. (2) Elevation had a significant influence on E p; however, the difference in daily E p between 2,480 m and 2,680 m was not significant, which was possibly due to the small difference in elevation between these two sites. (3) VWC had larger range of annual variation at 2,680 m than at 2,480 m, especially for the surface soil layer.We conclude that the decrease in temperature does not effectively explain the sharp transition between these forest types. During the dry season, plants growing at 2,680 m are likely to experience more drought stress. In seeking to understand the mountain forest distribution, further studies should consider the effects of drought stress alongside those of altitude.

  17. Mantle heterogeneity and temperatures inferred from magmas from different tectonic settings

    NASA Astrophysics Data System (ADS)

    Green, D. H.

    2003-04-01

    In many earth models, Mid-Ocean Ridge magmatism is attributed to decompression melting of upwelling upper mantle/asthenosphere at normal mantle temperature. By contrast, upwelling of anomalously high temperature deep mantle plumes is invoked as the cause of "hot spots" (Hawaii, Iceland). The compositions of olivine phenocrysts in picritic magmas define both the coexisting magma composition and the temperature of crystallization. Olivine phenocrysts in Mid-Ocean Ridge tholeiitic picrites and in Hawaiian picrites range up to Mg#92.1 and Mg#91.3 respectively. The anhydrous liquidus temperatures (1 bar pressure) of N-MORB picrites average 1335^oC, of E-MORB picrites average 1355^oC and of Hawaiian picrites average 1365^oC. Correction of liquidus temperatures for dissolved volatiles leads to the conclusion that magma temperatures for all types were approximately 1325^oC implying mantle potential temperature Tp˜1430^oC. The evidence from magmatic temperatures and compositions is that the temperature contrast between the magmatic products of "hot spots" and mid-ocean ridges is <= 20^oC. The study of distinctive primitive magmas from back-arc basins (tholeiitic picrite) and island arcs (boninite, picritic ankaramite), using both the phenocryst phase of the magmas themselves, and experimental studies of picrites and peridotites demonstrate significant roles for volatiles (C-H-O fluids) and for addition of components from the subducted slab into the overlying mantle wedge. Mantle potential temperatures of Tp˜ 1430^oC are also appropriate for these settings. As well as demonstrating consistent mantle potential temperature in upwelling regions of different tectonic settings, the constraints from experimental studies of liquid/residue equilibria require mantle compositional heterogeneity in major elements and mineral phases. Refractory elements (Cr, Mg, Ni) and phase relationships (chromite-bearing harzburgite vs spinel-bearing lherzolite residues) provide signatures for

  18. NMR metabolomic analysis of exhaled breath condensate of asthmatic patients at two different temperatures.

    PubMed

    Motta, Andrea; Paris, Debora; D'Amato, Maria; Melck, Dominique; Calabrese, Cecilia; Vitale, Carolina; Stanziola, Anna A; Corso, Gaetano; Sofia, Matteo; Maniscalco, Mauro

    2014-12-05

    Exhaled breath condensate (EBC) collection is a noninvasive method to investigate lung diseases. EBC is usually collected with commercial/custom-made condensers, but the optimal condensing temperature is often unknown. As such, the physical and chemical properties of exhaled metabolites should be considered when setting the temperature, therefore requiring validation and standardization of the collecting procedure. EBC is frequently used in nuclear magnetic resonance (NMR)-based metabolomics, which unambiguously recognizes different pulmonary pathological states. Here we applied NMR-based metabolomics to asthmatic and healthy EBC samples collected with two commercial condensers operating at -27.3 and -4.8 °C. Thirty-five mild asthmatic patients and 35 healthy subjects were included in the study, while blind validation was obtained from 20 asthmatic and 20 healthy different subjects not included in the primary analysis. We initially analyzed the samples separately and assessed the within-day, between-day, and technical repeatabilities. Next, samples were interchanged, and, finally, all samples were analyzed together, disregarding the condensing temperature. Partial least-squares discriminant analysis of NMR spectra correctly classified samples, without any influence from the temperature. Input variables were either integral bucket areas (spectral bucketing) or metabolite concentrations (targeted profiling). We always obtained strong regression models (95%), with high average-quality parameters for spectral profiling (R(2) = 0.84 and Q(2) = 0.78) and targeted profiling (R(2) = 0.91 and Q(2) = 0.87). In particular, although targeted profiling clustering is better than spectral profiling, all models reproduced the relative metabolite variations responsible for class differentiation. This warrants that cross comparisons are reliable and that NMR-based metabolomics could attenuate some specific problems linked to standardization of EBC collection.

  19. The Statistical Differences Between the Gridded Temperature Datasets, and its Implications for Stochastic Modelling

    NASA Astrophysics Data System (ADS)

    Fredriksen, H. B.; Løvsletten, O.; Rypdal, M.; Rypdal, K.

    2014-12-01

    Several research groups around the world collect instrumental temperature data and combine them in different ways to obtain global gridded temperature fields. The three most well known datasets are HadCRUT4 produced by the Climatic Research Unit and the Met Office Hadley Centre in UK, one produced by NASA GISS, and one produced by NOAA. Recently Berkeley Earth has also developed a gridded dataset. All these four will be compared in our analysis. The statistical properties we will focus on are the standard deviation and the Hurst exponent. These two parameters are sufficient to describe the temperatures as long-range memory stochastic processes; the standard deviation describes the general fluctuation level, while the Hurst exponent relates the strength of the long-term variability to the strength of the short-term variability. A higher Hurst exponent means that the slow variations are stronger compared to the fast, and that the autocovariance function will have a stronger tail. Hence the Hurst exponent gives us information about the persistence or memory of the process. We make use of these data to show that data averaged over a larger area exhibit higher Hurst exponents and lower variance than data averaged over a smaller area, which provides information about the relationship between temporal and spatial correlations of the temperature fluctuations. Interpolation in space has some similarities with averaging over space, although interpolation is more weighted towards the measurement locations. We demonstrate that the degree of spatial interpolation used can explain some differences observed between the variances and memory exponents computed from the various datasets.

  20. Film Thickness and Flow Properties of Resin-Based Cements at Different Temperatures

    PubMed Central

    Bagheri, R

    2013-01-01

    Statement of Problem: For a luting agent to allow complete seating of prosthetic restorations, it must obtain an appropriate flow rate maintaining a minimum film thickness. The performance of recently introduced luting agents in this regard has not been evaluated. Purpose: To measure and compare the film thickness and flow properties of seven resin-containing luting cements at different temperatures (37°C, 25°C and10°C). Material and Methods: Specimens were prepared from five resin luting cements; seT (SDI), Panavia F (Kuraray), Varioloink II (Ivoclar), Maxcem (Kerr), Nexus2 (Kerr) and two resin-modified glass-ionomer luting cements (RM-GICs); GC Fuji Plus (GC Corporation), and RelyX Luting 2 (3 M/ESPE). The film thickness and flow rate of each cement (n=15) was determined using the test described in ISO at three different temperatures. Results: There was a linear correlation between film thickness and flow rate for most of the materials. Cooling increased fluidity of almost all materials while the effect of temperature on film thickness was material dependent. At 37°C, all products revealed a film thickness of less than 25µm except for GC Fuji Plus. At 25°C, all cements produced a film thickness of less than 27 µm except for seT. At 10°C, apart from seT and Rely X Luting 2, the remaining cements showed a film thickness smaller than 20 µm. Conclusion: Cooling increased fluidity of almost all materials, however. the film thickness did not exceed 35 µm in either condition, in spite of the lowest film thickness being demonstrated at the lowest temperature. PMID:24724120

  1. Mass, phylogeny, and temperature are sufficient to explain differences in metabolic scaling across mammalian orders?

    PubMed

    Griebeler, Eva Maria; Werner, Jan

    2016-12-01

    Whether basal metabolic rate-body mass scaling relationships have a single exponent is highly discussed, and also the correct statistical model to establish relationships. Here, we aimed (1) to identify statistically best scaling models for 17 mammalian orders, Marsupialia, Eutheria and all mammals, and (2) thereby to prove whether correcting for differences in species' body temperature and their shared evolutionary history improves models and their biological interpretability. We used the large dataset from Sieg et al. (The American Naturalist174, 2009, 720) providing species' body mass (BM), basal metabolic rate (BMR) and body temperature (T). We applied different statistical approaches to identify the best scaling model for each taxon: ordinary least squares regression analysis (OLS) and phylogenetically informed analysis (PGLS), both without and with controlling for T. Under each approach, we tested linear equations (log-log-transformed data) estimating scaling exponents and normalization constants, and such with a variable normalization constant and a fixed exponent of either ⅔ or ¾, and also a curvature. Only under temperature correction, an additional variable coefficient modeled the influence of T on BMR. Except for Pholidata and Carnivora, in all taxa studied linear models were clearly supported over a curvature by AICc. They indicated no single exponent at the level of orders or at higher taxonomic levels. The majority of all best models corrected for phylogeny, whereas only half of them included T. When correcting for T, the mathematically expected correlation between the exponent (b) and the normalization constant (a) in the standard scaling model y = a x(b) was removed, but the normalization constant and temperature coefficient still correlated strongly. In six taxa, T and BM correlated positively or negatively. All this hampers a disentangling of the effect of BM, T and other factors on BMR, and an interpretation of linear BMR-BM scaling

  2. Temperature effect on the mechanical properties of gold nano films with different thickness

    NASA Astrophysics Data System (ADS)

    Birleanu, C.; Pustan, M.; Merie, V.; Müller, R.; Voicu, R.; Baracu, A.; Craciun, S.

    2016-08-01

    The microelectronic industry has been growing rapidly over the past 10-20 years, as has its reliance on thin-film deposition techniques for components manufacturing. As modern devices generate quite a bit of heat and peak temperatures can reach over 100°C, there is a need to provide adequate cooling for a device to stay operable. A series of chrome gold films with various thicknesses were prepared on silicon substrate. The structural and surface morphology, adhesion, friction, Young's modulus and hardness of this thin film were studied for three different thicknesses under temperature variations between 20 to 100°C. The variation of the film thickness and temperature affects the structure, surface and mechanical properties of Cr/Au thin films. Obviously these thermal cycles are unavoidable and eventually lead to thermal fatigue damage and device failure. Consequently, the knowledge of mechanical properties of thin films at elevated temperatures is required for proper chip design and reliability assessments. Elastic modulus and hardness are two important mechanical properties of the thin-film structural materials used in microelectromechanical systems. The mechanical properties of electroplated chrome-gold thin film are found to be highly dependent on the manufacturing process and also of the thin film thickness. On the other hand it is important to find the effect of temperature on these properties. Investigated samples are made of thin layers of chromium and gold with differences in thickness. The three levels of nominal thicknesses of Au films are: 100, 300 and 500 nm. In order to obtain the relations between surface pattern/surface chemistry and nanotribological properties and adhesive behaviors of the films were evaluated with a noise- and vibration-isolated and environment-controlled XE 70-AFM from Park Systems, using the contact mode. The tests were performed at temperatures between 10°C - 100°C and at a relative humidity RH of 40%. Each measurement was

  3. Microbial biomass and activity in soils with different moisture content heated at high temperatures

    NASA Astrophysics Data System (ADS)

    Barreiro, Ana; Lombao, Alba; Martin, Angela; Cancelo-González, Javier; Carballas, Tarsy; Díaz-Raviña, Montserrat

    2015-04-01

    It is well known that soil properties determining the thermal transmissivity (moisture, texture, organic matter, etc.) and the duration and temperatures reached during soil heating are key factors driving the fire-induced changes in soil microbial communities. However, despite its interest, the information about this topic is scarce. The aim of the present study is to analyze, under laboratory conditions, the impact of the thermal shock (infrared lamps reaching temperatures of 100 °C, 200 °C and 400 °C) on microbial communities of three acid soils under different moisture level (0 %, 25 % and 50 % per soil volume). Soil temperature was measured with thermocouples and the impact of soil heating was evaluated by means of the analysis of the temperature-time curves calculating the maximum temperature reached (Tmax) and the degree-hours (GH) as an estimation of the amount of heat supplied to the samples (fire severity). The bacterial growth (leucine incorporation) and the total microbial biomass (PLFA) were measured immediately after the heating and one month after the incubation of reinoculated soils. The results showed clearly the importance of moisture level in the transmission of heat through the soil and hence in the further direct impact of high temperatures on microorganisms living in soil. In general, the values of microbial parameters analyzed were low, particularly immediately after soil heating at higher temperatures; the bacterial activity measurements (leucine incorporation technique) being more sensitive to detect the thermal shock showed than total biomass measurements (PLFA). After 1 month incubation, soil microbial communities tend to recover due to the proliferation of surviving population using as substrate the dead microorganisms (soil sterilization). Thus, time elapsed after the heating was found to be decisive when examining the relationships between the microbial properties and the soil heating parameters (GH, Tmax). Analysis of results also

  4. Combined effects of the herbicide terbuthylazine and temperature on different flagellates from the Northern Adriatic Sea.

    PubMed

    Fiori, Emanuela; Mazzotti, Matilde; Guerrini, Franca; Pistocchi, Rossella

    2013-03-15

    The triazinic herbicide terbuthylazine (TBA) is becoming an emergent contaminant in Italian rivers and in coastal and groundwater. A preliminary analysis of the sensitivity of marine flagellates to TBA was performed by monitoring the photosynthetic efficiency of nine species (belonging to the Dinophyceae or Raphidophyceae class) isolated from the Adriatic Sea. Different sensitivity levels for each flagellate were observed and the most sensitive microalgae, based on PSII inhibition, were: Gonyaulax spinifera>Fibrocapsa japonica>Lingulodinium polyedrum while the most resistant were two species belonging to the Prorocentrum genus. Then the response of two microalgae to drivers, such as temperature and terbuthylazine, applied in combination was also investigated. Two potentially toxic flagellates, Prorocentrum minimum and G. spinifera, were exposed, under different temperature conditions (15, 20 and 25°C), to TBA concentrations that did not completely affect PSII. For both flagellates, effects of TBA on algal growth, measured through cell density and carbon analysis, as well as on the photosynthetic activity are reported. All parameters analyzed showed a negative effect of TBA from the exponential phase. TBA effect on algal growth was significantly enhanced at the optimal temperature conditions (20 and 25°C), while no difference between control and herbicide treatments were detected for G. spinifera grown at 15°C, which represented a stress condition for this species. The maximum inhibition of photosynthetic efficiency was found at 20°C for both organisms. Both flagellates increased cell carbon and nitrogen content in herbicide treatments compared to the control, except G. spinifera grown at 15°C. Chlorophyll-a production was increased only in G. spinifera exposed to 5 μg L(-1) of TBA and the effect was enhanced with the increase of temperature. Herbicide-induced variations in cellular components determined changes in cellular carbon:nitrogen (C:N) and

  5. Low temperature embrittlement behaviour of different ferritic-martensitic alloys for fusion applications

    NASA Astrophysics Data System (ADS)

    Rieth, M.; Dafferner, B.

    1996-10-01

    In the last few years a lot of different low activation CrWVTa steels have been developed world-wide. Without irradiation some of these alloys show clearly a better low temperature embrittlement behaviour than commercial CrNiMoV(Nb) alloys. Within the MANITU project a study was carried out to compare, prior to the irradiation program, the embrittlement behaviour of different alloys in the unirradiated condition performing instrumented Charpy impact bending tests with sub-size specimens. The low activation materials (LAM) considered were different OPTIFER alloys (Forschungszentrum Karlsruhe), F82H (JAERI), 9Cr2WVTa (ORNL), and GA3X (PNL). The modified commercial 10-11% CrNiMoVNb steels were MANET and OPTIMAR. A meaningful comparison between these alloys could be drawn, since the specimens of all materials were manufactured and tested under the same conditions.

  6. Specificity of genome evolution in experimental populations of Escherichia coli evolved at different temperatures

    PubMed Central

    Deatherage, Daniel E.; Kepner, Jamie L.; Bennett, Albert F.; Lenski, Richard E.; Barrick, Jeffrey E.

    2017-01-01

    Isolated populations derived from a common ancestor are expected to diverge genetically and phenotypically as they adapt to different local environments. To examine this process, 30 populations of Escherichia coli were evolved for 2,000 generations, with six in each of five different thermal regimes: constant 20 °C, 32 °C, 37 °C, 42 °C, and daily alternations between 32 °C and 42 °C. Here, we sequenced the genomes of one endpoint clone from each population to test whether the history of adaptation in different thermal regimes was evident at the genomic level. The evolved strains had accumulated ∼5.3 mutations, on average, and exhibited distinct signatures of adaptation to the different environments. On average, two strains that evolved under the same regime exhibited ∼17% overlap in which genes were mutated, whereas pairs that evolved under different conditions shared only ∼4%. For example, all six strains evolved at 32 °C had mutations in nadR, whereas none of the other 24 strains did. However, a population evolved at 37 °C for an additional 18,000 generations eventually accumulated mutations in the signature genes strongly associated with adaptation to the other temperature regimes. Two mutations that arose in one temperature treatment tended to be beneficial when tested in the others, although less so than in the regime in which they evolved. These findings demonstrate that genomic signatures of adaptation can be highly specific, even with respect to subtle environmental differences, but that this imprint may become obscured over longer timescales as populations continue to change and adapt to the shared features of their environments. PMID:28202733

  7. Effect of Different Denture Base Materials and Changed Mouth Temperature on Dimensional Stability of Complete Dentures.

    PubMed

    Arafa, Khalid A O

    2016-01-01

    Background. Type of materials used in fabrication of denture base has an effect on dimension during denture base material processing and other factors related to clinical use. Objective. The study aims were to assess the dimensional stability including thermal changes of three different denture base materials. Methods. Ninety patients were selected to construct complete dentures with different denture base materials. They were randomly divided into three groups: group 1, patients with cobalt chrome metallic base; group 2, patients with heat curing acrylic resin fabricated by injection moulding technique; and group 3, patients with denture bases fabricated by conventional heat curing acrylic resin. The dimensional changes were assessed using digital caliper. Results. After the twelfth month, injection moulding acrylic resin had significantly the highest dimensional change followed by the conventional heat curing acrylic resin. There were no significant differences in the dimensions between the three types of denture base materials at normal mouth temperature, while, after hot tea drinking at 45°C, the dimensional change was significantly the highest in cobalt chrome metallic denture base group. Conclusion. Cobalt chrome metallic denture base has stable dimension compared to denture bases fabricated of acrylic resin but it was more affected by altered mouth temperature. The study was registered in the International Standard Randomized Controlled Trials Number (ISRCTN) registry with study ID (ISRCTN94238244).

  8. Evaluating Fracture Toughness of Rolled Zircaloy-2 at Different Temperatures Using XFEM

    NASA Astrophysics Data System (ADS)

    Goel, Sunkulp; Kumar, Nikhil; Fuloria, Devasri; Jayaganthan, R.; Singh, I. V.; Srivastava, D.; Dey, G. K.; Saibaba, N.

    2016-09-01

    Fracture toughness and mechanical properties of the zircaloy-2 processed by rolling at different temperatures have been investigated, and simulations have been performed using extended finite element method (XFEM). The solutionized alloy was rolled at different temperatures for different thickness reductions (25-85%). Fracture toughness has been investigated by compact tension test. The improved fracture toughness of the rolled zircaloy-2 samples is due to high dislocation density. SEM image of the fractured surface shows the reduction in dimple sizes with the increase in dislocation density due to the formation of microvoids as a result of severe strain induced during rolling. Compact tension test, edge crack, center crack and three-point bend specimen simulations have been performed by XFEM. In XFEM, the cracks are not a part of finite element mesh and are modeled by adding enrichment function in the standard finite element displacement approximation. The XFEM results obtained for compact tension test have been found to be in good agreement with the experiment.

  9. Magnetic piston model for higher ion charge and different electron and ion plasma temperatures

    SciTech Connect

    Bogatu, I. N.

    2013-05-15

    A new formula for the magnetic piston model, which explicitly describes how the momentum imparted to the ions by the magnetic pressure depends not only on the ion mass but also on the ion charge, as well as, on the plasma electron and ion temperatures, is derived following Rosenbluth's classical particle-field self-consistent plane approximation analytic calculation. The formula presented in this paper has implications in explaining the experimentally observed separation of the ions of different species and charges by the magnetic field penetrating the plasma and specularly reflecting them.

  10. Role of different scattering mechanisms on the temperature dependence of transport in graphene

    PubMed Central

    Sarkar, Suman; Amin, Kazi Rafsanjani; Modak, Ranjan; Singh, Amandeep; Mukerjee, Subroto; Bid, Aveek

    2015-01-01

    Detailed experimental and theoretical studies of the temperature dependence of the effect of different scattering mechanisms on electrical transport properties of graphene devices are presented. We find that for high mobility devices the transport properties are mainly governed by completely screened short range impurity scattering. On the other hand, for the low mobility devices transport properties are determined by both types of scattering potentials - long range due to ionized impurities and short range due to completely screened charged impurities. The results could be explained in the framework of Boltzmann transport equations involving the two independent scattering mechanisms. PMID:26608479

  11. Hawking radiation temperatures in non-stationary Kerr black holes with different tortoise coordinate transformations

    NASA Astrophysics Data System (ADS)

    Lan, X. G.; Jiang, Q. Q.; Wei, L. F.

    2012-04-01

    We apply the Damour-Ruffini-Sannan method to study the Hawking radiations of scalar and Dirac particles in non-stationary Kerr black holes under different tortoise coordinate transformations. We found that all the relevant Hawking radiation spectra show still the blackbody ones, while the Hawking temperatures are strongly related to the used tortoise coordinate transformations. The properties of these dependences are discussed analytically and numerically. Our results imply that proper selections of tortoise coordinate transformations should be important in the studies of Hawking radiations and the correct selection would be given by the experimental observations in the future.

  12. Analysis of normalized difference and surface temperature observations over southeastern Australia

    NASA Technical Reports Server (NTRS)

    Smith, R. C. G.; Choudhury, B. J.

    1991-01-01

    Relations between radiative surface temperature (TR) and visible and near-IR reflectances expressed as the normalized difference (ND) from a Landsat Thematic Mapper scene are analyzed to examine the heat balance of agriculture and native evergreen forests in southeastern Australia. Factors determining the residual scatter about, and slope of, the TR/ND relationships were analyzed using a coupled two-layer soil-vegetation model of the surface heat balance. Inverse linear relationships were observed between TR and ND for agriculture, but not for forests. This was due to a wide range of ND and TR values in agricultural regions caused by wide variations in fractional vegetation cover.

  13. Investigation of mass transfer between two parallel walls at different temperatures by a moment method

    NASA Technical Reports Server (NTRS)

    Sloat, T. N.; Edwards, R. H.; Collins, R. L.

    1971-01-01

    One-dimensional flow between two fixed parallel walls composed of the same substance but at different temperatures and spaced a distance 1 apart is considered. The hot plate is the evaporating surface (source) and the cold plate is the condensing surface (sink). The vapor between the two plates is assumed to be a monatomic gas consisting of Maxwell molecules. Lee's moment method is used to obtain a set of six nonlinear equations. Both the nonlinear equations and a linearized approximation to them are solved.

  14. Structural variation of glycolipids from Meiothermus taiwanensis ATCC BAA-400 under different growth temperatures.

    PubMed

    Yang, Yu-Liang; Yang, Feng-Ling; Huang, Zih-You; Tsai, Yu-Hsuan; Zou, Wei; Wu, Shih-Hsiung

    2010-10-07

    A major glycolipid, alpha-Galf(1-3)-alpha-Galp(1-6)-beta-GlcpNAcyl(1-2)-alpha-Glcp(1-1)-2-acylalkyldiol, is obtained from Meiothermus taiwanensis. This novel glycolipid is found only when the bacterium grows above 62 degrees C, which is significantly different from those from the same bacteria incubated at 55 degrees C. Terminal galactofuranoside and 1,2-alkyldiol lipids replaced galactopyranoside and glycerol lipids, respectively, under increased growth temperature. This variation is likely necessary for bacteria for keeping the stable outer membrane and surviving under extreme environments.

  15. Strain Rate Effects and Temperature History Effects for Three Different Tempers of 4340 VAR Steel

    DTIC Science & Technology

    1984-07-01

    45, pp 60-66 March, 1978. 17. C.F. Hickey, Jr. and A. A. Anctil, "Split Heat Mechanical Property Comparison of ESR and VAR 4340 Steel ", A•MMRC...Embrittlement in High Hardness ESR 4340 Steel Forgings", ANMRC Technical Report 82-1, Army Materials and Mechanics Research Center, Watertown, Mass, January, 1982...Effects and Temperature History Effects for Three Different Tempers of 4340 VAR Steel . 0 by S. Tanimura and J. Duffy DTICr:fti Army Research Office . . 1

  16. Effects of different extraction temperatures on the physicochemical properties of bioactive polysaccharides from Grifola frondosa.

    PubMed

    Su, Chun-Han; Lai, Min-Nan; Ng, Lean-Teik

    2017-04-01

    This study examined the effects of different extraction temperatures (70°C, 100°C and 121°C) on the physicochemical properties of water soluble polysaccharides (WSP; GF70, GF100 and GF121, respectively) from Grifola frondosa (GF) fruiting bodies, and evaluating their effects on nitric oxide (NO) production in lipopolysaccharide-stimulated RAW264.7 macrophages. Results showed that GF121 had the highest yield. GF70, GF100 and GF121 contained a similar monosaccharide composition and the predominant monosaccharide was glucose. These polysaccharides contained two major macromolecular populations; the high molecular weight population showed a clear trend of reduced molecular weight with increasing extraction temperature. GF121 contained the highest amount of (1→3, 1→6)-β-d-glucans, while the degree of branching in all samples was similar. GF WSP possessed NO inhibitory activity, and the strongest was GF121. This study concludes that WSP are good sources of food ingredients, and high temperature extraction could improve the quantity and quality of GF WSP.

  17. Influence of different rubber dam application on intraoral temperature and relative humidity.

    PubMed

    Haruyama, Akiko; Kameyama, Atsushi; Tatsuta, Chihiro; Ishii, Kurumi; Sugiyama, Toshiko; Sugiyama, Setsuko; Takahashi, Toshiyuki

    2014-01-01

    The purpose of this study was to investigate the effect of type of rubber dam and application method on the moisture exclusion effect. The intraoral temperature and relative humidity were compared among various moisture exclusion appliances. Various dry field techniques were applied to 5 subjects and intraoral temperature and relative humidity measured 5 min after placing a digital hygro-thermometer in the mouth. The relative humidity was 100% in all subjects when moisture was excluded by means of cotton rolls alone. When only tooth 36 was exposed, relative humidity was significantly lower with latex, urethane, or 3-dimensional sheets than with cotton rolls alone, and was similar to the level of humidity in the room. When a local rubber dam was used, the relative humidity was significantly higher than the indoor humidity (p<0.05). No significant differences were noted in the intraoral temperature or relative humidity between exposure of 4 teeth and 1 tooth, but variation in the relative humidity was more marked in 4- than in 1-tooth exposure. The creation of an air vent did not influence the moisture exclusion effect. These results suggest that the rubber dam isolation technique excludes moisture to a level equivalent to the humidity in the room when only a single tooth is exposed, but the moisture exclusion effect may be inconsistent when several teeth are exposed.

  18. Analysis of epidermal/dermal temperature changes according to the different cryogen spray cooling conditions.

    PubMed

    Jo, Jung Ho; Jo, Su Hyun; Lee, Ju Hwan; Kim, Ga Young; Kim, Sung Min

    2015-09-10

    This study measured epidermal and dermal temperatures under different cryogen spray cooling (CSC) conditions to determine the optimum cooling conditions for skin rejuvenation. For this purpose, CSC conditions were applied before a laser transmission for varying spurt times of 50, 150, and 200 ms with delay times of 150 and 200 ms. A long-pulsed 1,064 nm Nd:YAG laser irradiated the skin surface of a pig with a condition of fluence of 26 J/cm2 and a spot diameter of 8 mm. The pulse duration was set to 30 ms during all experiments. This study found that all employed CSC conditions significantly decreased internal-external skin temperatures. Moreover, skin temperatures were influenced more by variations in spurt time of CSC compared with the delay times. Based on these experimental results, two spurt times were selected as the optimum CSC conditions for skin rejuvenation: 50 ms with delay time of 150 and 200 ms and 150 ms with a delay time of 150 and 200 ms.

  19. Analysis of epidermal/dermal temperature changes according to the different cryogen spray cooling conditions.

    PubMed

    Jo, Jung Ho; Jo, Su Hyun; Lee, Ju Hwan; Kim, Ga Young; Kim, Sung Min

    2015-01-01

    This study measured epidermal and dermal temperatures under different cryogen spray cooling (CSC) conditions to determine the optimum cooling conditions for skin rejuvenation. For this purpose, CSC conditions were applied before a laser transmission for varying spurt times of 50, 150, and 200 ms with delay times of 150 and 200 ms. A long-pulsed 1,064 nm Nd:YAG laser irradiated the skin surface of a pig with a condition of fluence of 26 J/cm2 and a spot diameter of 8 mm. The pulse duration was set to 30 ms during all experiments. This study found that all employed CSC conditions significantly decreased internal-external skin temperatures. Moreover, skin temperatures were influenced more by variations in spurt time of CSC compared with the delay times. Based on these experimental results, two spurt times were selected as the optimum CSC conditions for skin rejuvenation: 50 ms with delay time of 150 and 200 ms and 150 ms with a delay time of 150 and 200 ms.

  20. Response of largemouth bass (Micropterus salmoides) from different thermal environments to increased water temperature.

    PubMed

    Mulhollem, Joshua J; Suski, Cory D; Wahl, David H

    2015-08-01

    Due to concerns of global climate change, additional research is needed to quantify the thermal tolerance of species, and how organisms are able to adapt to changes in thermal regime. We quantified the thermal tolerance and thermal stress response of a temperate sportfish from two different thermal environments. One group of largemouth bass (Micropterus salmoides) inhabited thermally enhanced reservoirs (used for power plant cooling), with water temperatures typically 2-5°C warmer than nearby reservoirs. We tested fish for chronic thermal maxima and reaction to an 8°C heat shock using three common physiological indices of stress. We observed no evidence of differences between groups in thermal maxima. We observed no differences in thermal maxima between fish from artificially warmed and natural systems. Our results disagree with research, suggesting differences due to adaptation to different thermal environments. We speculate that behavioral modifications, lack of adequate time for genetic divergence, or the robust genetic plasticity of largemouth bass explain the lack of difference between treatment groups.

  1. Differences in cyanobacterial strain responses to light and temperature reflect species plasticity.

    PubMed

    Xiao, Man; Willis, Anusuya; Burford, Michele A

    2017-02-01

    Microcystis aeruginosa and Cylindrospermopsis raciborskii are two cyanobacterial species that dominate freshwaters globally. Multiple strains of each species with different physiology occur, however, many studies have focused only on one or two strains, limiting our understanding of both strain variation and characterisation of the species. Therefore, in this study we examined the variation in growth and morphology of multiple isolates of both species, isolated from two adjacent Australian reservoirs. Four M. aeruginosa strains (=isolates) (one colony-forming, three single-celled morphology) and eight C. raciborskii isolates (five with straight trichomes, three with coiled trichomes) were cultured individually in a factorial designed experiment with four light intensities (L: 10, 30, 50 and 100μmol photons m(-2)s(-1)) and two temperatures (T: 20 and 28°C). The specific growth rate (μ), cell volume, and final cell concentration was measured. The light attenuation coefficient (kj), a measure of self-shading, was calculated. The results showed that the intraspecific variation was greater than the interspecific variation. The μ of all isolates of M. aeruginosa and C. raciborskii ranged from 0.16 to 0.55d(-1) and 0.15 to 0.70d(-1), respectively. However, at a specific light and temperature the mean μ of all M. aeruginosa isolates and C. raciborskii isolates were similar. At the species level, M. aeruginosa had higher growth rates at higher light intensity but lower temperature (L100T20), while straight C. raciborskii had higher growth rates at lower light intensity but higher temperature (L50T28), and coiled C. raciborskii had higher growth rates at higher light intensity and higher temperature (L100T28). The final cell concentrations of M. aeruginosa were higher than C. raciborskii. However, C. raciborskii isolates had greater variation in μ, kj and cell volume than M. aeruginosa. kj varied with light and temperature, and decreased with surface-to-volume ratio

  2. Studies on intermolecular interaction on binary mixtures of methyl orange-water system: excess molar functions of ultrasonic parameters at different concentrations and at different temperatures.

    PubMed

    Thanuja, B; Kanagam, Charles; Sreedevi, S

    2011-11-01

    Density (ρ), viscosity (η) and ultrasonic velocity (u) of binary mixtures of methyl orange and water were measured at different concentrations and at different temperatures; several useful parameters such as excess volume, excess velocity, and excess adiabatic compressibility have been calculated. These parameters are used to explain the nature of intermolecular interactions taking place in the binary mixture. The above study is helpful in understanding the dye/solvent interaction at different concentration and temperatures.

  3. Plasma osmolality and oxygen consumption of perch Perca fluviatilis in response to different salinities and temperatures.

    PubMed

    Christensen, E A F; Svendsen, M B S; Steffensen, J F

    2017-03-01

    The present study determined the blood plasma osmolality and oxygen consumption of the perch Perca fluviatilis at different salinities (0, 10 and 15) and temperatures (5, 10 and 20° C). Blood plasma osmolality increased with salinity at all temperatures. Standard metabolic rate (SMR) increased with salinity at 10 and 20° C. Maximum metabolic rate (MMR) and aerobic scope was lowest at salinity of 15 at 5° C, yet at 20° C, they were lowest at a salinity of 0. A cost of osmoregulation (SMR at a salinity of 0 and 15 compared with SMR at a salinity of 10) could only be detected at a salinity of 15 at 20° C, where it was 28%. The results show that P. fluviatilis have capacity to osmoregulate in hyper-osmotic environments. This contradicts previous studies and indicates intraspecific variability in osmoregulatory capabilities among P. fluviatilis populations or habitat origins. An apparent cost of osmoregulation (28%) at a salinity of 15 at 20° C indicates that the cost of osmoregulation in P. fluviatilis increases with temperature under hyperosmotic conditions and a power analysis showed that the cost of osmoregulation could be lower than 12·5% under other environmental conditions. The effect of salinity on MMR is possibly due to a reduction in gill permeability, initiated to reduce osmotic stress. An interaction between salinity and temperature on aerobic scope shows that high salinity habitats are energetically beneficial during warm periods (summer), whereas low salinity habitats are energetically beneficial during cold periods (winter). It is suggested, therefore, that the seasonal migrations of P. fluviatilis between brackish and fresh water is to select an environment that is optimal for metabolism and aerobic scope.

  4. Individual differences in temperature perception: evidence of common processing of sensation intensity of warmth and cold.

    PubMed

    Green, Barry G; Akirav, Carol

    2007-01-01

    The longstanding question of whether temperature is sensed via separate sensory systems for warmth and cold was investigated by measuring individual differences in perception of nonpainful heating and cooling. Sixty-two subjects gave separate ratings of the intensity of thermal sensations (warmth, cold) and nociceptive sensations (burning/stinging/pricking) produced by cooling (29 degrees C) or heating (37 degrees C) local regions of the forearm. Stimuli were delivered via a 4 x 4 array of 8 mm x 8 mm Peltier thermoelectric modules that enabled test temperatures to be presented sequentially to individual modules or simultaneously to the full array. Stimulation of the full array showed that perception of warmth and cold were highly correlated (Pearson r = 0.83, p < 0.05). Ratings of nonpainful nociceptive sensations produced by the two temperatures were also correlated, but to a lesser degree (r = 0.44), and the associations between nociceptive and thermal sensations (r = 0.35 and 0.22 for 37 and 29 degrees C, respectively) were not significant after correction for multiple statistical tests. Intensity ratings for individual modules indicated that the number of responsive sites out of 16 was a poor predictor of temperature sensations but a significant predictor of nociceptive sensations. The very high correlation between ratings of thermal sensations conflicts with the classical view that warmth and cold are mediated by separate thermal modalities and implies that warm-sensitive and cold-sensitive spinothalamic pathways converge and undergo joint modulation in the central nervous system. Integration of thermal stimulation from the skin and body core within the thermoregulatory system is suggested as the possible source of this convergence.

  5. Relating trends in land surface-air temperature difference to soil moisture and evapotranspiration

    NASA Astrophysics Data System (ADS)

    Veal, Karen; Taylor, Chris; Gallego-Elvira, Belen; Ghent, Darren; Harris, Phil; Remedios, John

    2016-04-01

    Soil water is central to both physical and biogeochemical processes within the Earth System. Drying of soils leads to evapotranspiration (ET) becoming limited or "water-stressed" and is accompanied by rises in land surface temperature (LST), land surface-air temperature difference (delta T), and sensible heat flux. Climate models predict sizable changes to the global water cycle but there is variation between models in the time scale of ET decay during dry spells. The e-stress project is developing novel satellite-derived diagnostics to assess the ability of Earth System Models (ESMs) to capture behaviour that is due to soil moisture controls on ET. Satellite records of LST now extend 15 years or more. MODIS Terra LST is available from 2000 to the present and the Along-Track Scanning Radiometer (ATSR) LST record runs from 1995 to 2012. This paper presents results from an investigation into the variability and trends in delta T during the MODIS Terra mission. We use MODIS Terra and MODIS Aqua LST and ESA GlobTemperature ATSR LST with 2m air temperatures from reanalyses to calculate trends in delta T and "water-stressed" area. We investigate the variability of delta T in relation to soil moisture (ESA CCI Passive Daily Soil Moisture), vegetation (MODIS Monthly Normalized Difference Vegetation Index) and precipitation (TRMM Multi-satellite Monthly Precipitation) and compare the temporal and spatial variability of delta T with model evaporation data (GLEAM). Delta T anomalies show significant negative correlations with soil moisture, in different seasons, in several regions across the planet. Global mean delta T anomaly is small (magnitude mostly less than 0.2 K) between July 2002 and July 2008 and decreases to a minimum in early 2010. The reduction in delta T anomaly coincides with an increase in soil moisture anomaly and NDVI anomaly suggesting an increase in evapotranspiration and latent heat flux with reduced sensible heat flux. In conclusion there have been

  6. Changes in exercise and post-exercise core temperature under different clothing conditions

    NASA Astrophysics Data System (ADS)

    Kenny, Glen P.; Reardon, Francis D.; Thoden, Jim S.; Giesbrecht, Gordon G.; Kenny, G.

    This study evaluates the effect of different levels of insulation on esophageal (Tes) and rectal (Tre) temperature responses during and following moderate exercise. Seven subjects completed three 18-min bouts of treadmill exercise (75% VO2max, 22°C ambient temperature) followed by 30 min of recovery wearing either: (1) jogging shoes, T-shirt and shorts (athletic clothing); (2) single-knit commercial coveralls worn over the athletic clothing (coveralls); or (3) a Canadian Armed Forces nuclear, bacteriological and chemical warfare protective overgarment with hood, worn over the athletic clothing (NBCW overgarment). Tes was similar at the start of exercise for each condition and baseline Tre was 0.4°C higher than Tes. The hourly equivalent rate of increase in Tes during the final 5 min of exercise was 1.8°C, 3.0°C and 4.2°C for athletic clothing, coveralls and NBCW overgarment respectively (P<0.05). End-exercise Tes was significantly different between conditions [37.7°C (SEM 0.1°C), 38.2°C (SEM 0.2°C and 38.5°C (SEM 0.2°C) for athletic clothing, coveralls and NBCW overgarment respectively)] (P<0.05). No comparable difference in the rate of temperature increase for Tre was demonstrated, except that end-exercise Tre for the NBCW overgarment condition was significantly greater (0.5°C) than that for the athletic clothing condition. There was a drop in Tes during the initial minutes of recovery to sustained plateaus which were significantly (P<0.05) elevated above pre-exercise resting values by 0.6°C, 0.8°C and 1.0°C, for athletic clothing, coveralls, and NBCW overgarment, respectively. Post-exercise Tre decreased very gradually from end-exercise values during the 30-min recovery. Only the NBCW overgarment condition Tre was significantly elevated (0.3°C) above the athletic clothing condition (P<0.05). In conclusion, Tes is far more sensitive in reflecting the heat stress of different levels of insulation during exercise and post-exercise than Tre

  7. Characterizing human skin blood flow regulation in response to different local skin temperature perturbations.

    PubMed

    Wu, Y; Nieuwenhoff, M D; Huygen, F J P M; van der Helm, F C T; Niehof, S; Schouten, A C

    2017-05-01

    Small nerve fibers regulate local skin blood flow in response to local thermal perturbations. Small nerve fiber function is difficult to assess with classical neurophysiological tests. In this study, a vasomotor response model in combination with a heating protocol was developed to quantitatively characterize the control mechanism of small nerve fibers in regulating skin blood flow in response to local thermal perturbation. The skin of healthy subjects' hand dorsum (n=8) was heated to 42°C with an infrared lamp, and then naturally cooled down. The distance between the lamp and the hand was set to three different levels in order to change the irradiation intensity on the skin and implement three different skin temperature rise rates (0.03°C/s, 0.02°C/s and 0.01°C/s). A laser Doppler imager (LDI) and a thermographic video camera recorded the temporal profile of the skin blood flow and the skin temperature, respectively. The relationship between the skin blood flow and the skin temperature was characterized by a vasomotor response model. The model fitted the skin blood flow response well with a variance accounted for (VAF) between 78% and 99%. The model parameters suggested a similar mechanism for the skin blood flow regulation with the thermal perturbations at 0.03°C/s and 0.02°C/s. But there was an accelerated skin vasoconstriction after a slow heating (0.01°C/s) (p-value<0.05). An attenuation of the skin vasodilation was also observed in four out of the seven subjects during the slow heating (0.01°C/s). Our method provides a promising way to quantitatively assess the function of small nerve fibers non-invasively and non-contact.

  8. Susceptibility to low-temperature photoinhibition in three conifers differing in successional status.

    PubMed

    Robakowski, Piotr

    2005-09-01

    Susceptibility to photoinhibition of the evergreen conifers Abies alba Mill., Picea abies (L.) Karst. and Pinus mugo Turra was investigated in an unheated greenhouse during winter and spring 2003. Photosynthetic performance of the seedlings was assessed by chlorophyll a fluorescence and analyses of chlorophyll and total carotenoid concentrations in needles. During winter months, maximum quantum yield of PSII photochemistry (ratio of variable to maximum fluorescence, Fv/Fm) was significantly greater in A. alba than in P. abies and P. mugo. Abies alba also sustained higher maximum apparent electron transport rate (ETRmax) than P. abies and P. mugo. Total concentrations of chlorophyll and carotenoids in needles decreased during the winter in P. mugo and P. abies, but remained stable in A. alba. For all species, Fv/Fm decreased from December until February and then increased to a maximum in April. Photoinhibition was greatest (Fv/Fm < 0.80) in all seedlings in February, the month with the lowest mean temperature. Saturating photosynthetic photon flux (PPFsat) and ETRmax were positively related to air temperature. All species had lower values of ETRmax and PPFsat in winter than in spring. Non-photochemical quenching of chlorophyll fluorescence (NPQ) was highest at low air temperatures. Differences among species in susceptibility to winter photoinhibition resulted from their specific light preferences and led to different mechanisms to cope with photoinhibitory stress. The more shade-tolerant A. alba sustained a higher photosynthetic capacity in winter than P. abies and P. mugo. Winter photoinhibition in P. abies, P. mugo and, to a lesser extent, in A. alba may reflect adaptive photoprotection of the photosynthetic apparatus in winter.

  9. Effect of different post mortem temperatures on carcass quality of suckling lamb.

    PubMed

    Rubio, Begoña; Vieira, Ceferina; Martínez, Beatriz; Fernández, Ana M

    2013-08-01

    The effect of post mortem treatment on microbiological lamb carcass quality was studied. Suckling lambs carcasses were assigned to three different post mortem treatments: conventional (2  for 24 h), ultra-rapid (-20  for 3.5 h then 2  until 24 h post mortem) and slow (12   for 7 h then 2  until 24 h post mortem). Carcass pH and temperature were measured at 0, 3.5, 7 and 24 h post slaughter. Lamb carcasses were sampled for total aerobic viable and Enterobacteriaceae counts just after dressing and 24 h post mortem. A significant effect (p < 0.05) of post mortem treatment on carcasses temperature and pH was found corresponding the faster pH fall to slowly chilled muscles. However, no differences were found at 24 h post mortem among treatments in both parameters. Regarding microbiological results, carcasses of ultra-rapid treatment had the lowest total aerobic viable and Enterobacteriaceae counts and those belonging to conventional treatment had the highest total aerobic viable counts. From 0 to 24 h post mortem, an increase of total aerobic viable was observed in conventional and slow treatments whilst Enterobacteriaceae counts remained constant in all cases. From a microbiological point of view, the ultra-rapid treatment was the only one allowed to maintain the hygienic carcasses quality. However, according to pH and temperature results the carcasses subjected to this treatment may be susceptible to cold shortening.

  10. Effects of high temperature on different restorations in forensic identification: Dental samples and mandible

    PubMed Central

    Patidar, Kalpana A; Parwani, Rajkumar; Wanjari, Sangeeta

    2010-01-01

    Introduction: The forensic odontologist strives to utilize the charred human dentition throughout each stage of dental evaluation, and restorations are as unique as fingerprints and their radiographic morphology as well as the types of filling materials are often the main feature for identification. The knowledge of detecting residual restorative material and composition of unrecovered adjacent restoration is a valuable tool-mark in the presumptive identification of the dentition of a burned victim. Gold, silver amalgam, silicate restoration, and so on, have a different resistance to prolonged high temperature, therefore, the identification of burned bodies can be correlated with adequate qualities and quantities of the traces. Most of the dental examination relies heavily on the presence of the restoration as well as the relationship of one dental structure to another. This greatly narrows the research for the final identification that is based on postmortem data. Aim: The purpose of this study is to examine the resistance of teeth and different restorative materials, and the mandible, to variable temperature and duration, for the purpose of identification. Materials and Methods: The study was conducted on 72 extracted teeth which were divided into six goups of 12 teeth each based on the type of restorative material. (Group 1 - unrestored teeth, group 2 - teeth restored with Zn3(PO4)2, group 3 - with silver amalgam, group 4 with glass ionomer cement, group 5 - Ni-Cr-metal crown, group 6 - metal ceramic crown) and two specimens of the mandible. The effect of incineration at 400°C (5 mins, 15 mins, 30 mins) and 1100°C (15 mins) was studied. Results: Damage to the teeth subjected to variable temperatures and time can be categorized as intact (no damage), scorched (superficially parched and discolored), charred (reduced to carbon by incomplete combustion) and incinerated (burned to ashes). PMID:21189989

  11. Dielectrical Properties of CeO2 Nanoparticles at Different Temperatures

    PubMed Central

    Zamiri, Reza; Abbastabar Ahangar, Hossein; Kaushal, Ajay; Zakaria, Azmi; Zamiri, Golnoosh; Tobaldi, David; Ferreira, J. M. F.

    2015-01-01

    A template-free precipitation method was used as a simple and low cost method for preparation of CeO2 nanoparticles. The structure and morphology of the prepared nanoparticle samples were studied in detail using X-ray diffraction, Raman spectroscopy and Scanning Electron Microscopy (SEM) measurements. The whole powder pattern modelling (WPPM) method was applied on XRD data to accurately measure the crystalline domain size and their size distribution. The average crystalline domain diameter was found to be 5.2 nm, with a very narrow size distribution. UV-visible absorbance spectrum was used to calculate the optical energy band gap of the prepared CeO2 nanoparticles. The FT-IR spectrum of prepared CeO2 nanoparticles showed absorption bands at 400 cm-1 to 450 cm-1 regime, which correspond to CeO2 stretching vibration. The dielectric constant (εr) and dielectric loss (tan δ) values of sintered CeO2 compact consolidated from prepared nanoparticles were measured at different temperatures in the range from 298 K (room temperature) to 623 K, and at different frequencies from 1 kHz to 1 MHz. PMID:25910071

  12. Wide Pressure Range Measurement due to the Exchange of Heater Driving of the Temperature Difference Sensor

    NASA Astrophysics Data System (ADS)

    Takashima, Noriaki; Kimura, Mitsuteru

    We have extended measurable pressure range of the thin film Pirani vacuum sensor that is still sensitive above 1×105 Pa (1 atmosphere). In our thin film Pirani vacuum sensor, our proposed temperature difference sensor of the short circuit Seebeck-current detection type thermocouple is used in order to get extremely high sensitivity, especially both in very low pressure range and in higher pressure range than 1×104 Pa. In our new pressure sensor the cantilever type sensing region, in which a microheater and two thermocouples are formed to measure the temperature difference, is adopted. Therefore, we can use the null method to measure very small pressure accurately in the high vacuum range (low pressure range). On the other hand in the higher pressure than 1×104 Pa., we could expand the pressure range by adoption of the vibration of the sensing cantilever based on the sudden heating due to the exchange of heater driving. We have achieved much wider measurable pressure range over 8 digits by use of our new simple thin film Pirani vacuum sensor than that of the traditional one.

  13. RNA stability in human liver: comparison of different processing times, temperatures and methods.

    PubMed

    Lee, Serene M L; Schelcher, Celine; Gashi, Sevdije; Schreiber, Stefanie; Thasler, Reinhard M K; Jauch, Karl-Walter; Thasler, Wolfgang E

    2013-01-01

    The accuracy of information garnered by real-time quantitative polymerase chain reaction (RT-qPCR), an important technology for elucidating molecular mechanisms of disease, is dependent on tissue quality. Thus, this study aimed to determine the effects of intra-operative manipulation, extended processing times, different temperatures or storage in RNAlater on RNA quality in liver samples for tissue banking. Liver samples, flash-frozen or in RNAlater, were collected over a time course (during surgery before blood arrest up to 1 day after surgery) with samples kept either at room temperature (RT) or on ice. This study showed that at the longest time-point at RT, the RNA quality decreased significantly by 20%. However, relative gene expressions of FOS, GUSB, MYC, HIF1α and GFER were in general not significantly different when the time-points were compared. In conclusion, samples should be kept on ice during processing, and either RNAlater or snap-freezing should be utilised for storage. Further, intra-operative manipulation and extended postoperative processing time generally does not change relative gene expression levels for the 5 genes studied, making such sampling suitable for RT-qPCR analysis. Thus, if relative gene expression of a gene of interest is stable, these guidelines will lead to increased accrual of samples to the tissue bank.

  14. Effects of plant growth substances on rooting of Hedychium spicatum under different temperature regimes.

    PubMed

    Giri, Dinesh; Tamta, Sushma

    2013-03-01

    Present study was carried out to develop a simple and efficient vegetative propagation protocol by applying various treatments to rhizome cuttings with different test solutions of auxins and phenolic compound. These were alpha-naphthalene acetic acid (NAA), Indole-3-butyric acid (IBA), Indole Acetic Acid (IAA), phloroglucinol and coumarin. The concentrations for each treatment were 10.0, 50.0 and 100.0 microM. After treatments the rhizome cuttings were planted in polybags containing forest soil and kept under different temperature regimes i.e., inside polyhose (at 20-25 degrees C), inside mist chamber (at 15-20 degrees C) and under nethouse (nursery condition, at 14-18 degrees C). The maximum rooting percentage (74.06%) was achieved at 20-25 degrees C (inside polyhouse) by applying 50.0 microM IBA. Inside poly house condition, the various developmental parameters showed better responses compare to other conditions. On the basis of present study emphasizes that the temperature play a crucial role in rooting and further growth of the plants in this species. By using this simple and significant conventional method of propagation we could be propagate this vulnerable medicinal and aromatic species at large scale for commercial purpose.

  15. Comparative analysis of selected exhaled breath biomarkers obtained with two different temperature-controlled devices

    PubMed Central

    2009-01-01

    Background The collection of exhaled breath condensate (EBC) is a suitable and non-invasive method for evaluation of airway inflammation. Several studies indicate that the composition of the condensate and the recovery of biomarkers are affected by physical characteristics of the condensing device and collecting circumstances. Additionally, there is an apparent influence of the condensing temperature, and often the level of detection of the assay is a limiting factor. The ECoScreen2 device is a new, partly single-use disposable system designed for studying different lung compartments. Methods EBC samples were collected from 16 healthy non-smokers by using the two commercially available devices ECoScreen2 and ECoScreen at a controlled temperature of -20°C. EBC volume, pH, NOx, LTB4, PGE2, 8-isoprostane and cys-LTs were determined. Results EBC collected with ECoScreen2 was less acidic compared to ECoScreen. ECoScreen2 was superior concerning condensate volume and detection of biomarkers, as more samples were above the detection limit (LTB4 and PGE2) or showed higher concentrations (8-isoprostane). However, NOx was detected only in EBC sampled by ECoScreen. Conclusion ECoScreen2 in combination with mediator specific enzyme immunoassays may be suitable for measurement of different biomarkers. Using this equipment, patterns of markers can be assessed that are likely to reflect the complex pathophysiological processes in inflammatory respiratory disease. PMID:19948050

  16. Constructal thermodynamics combined with infrared experiments to evaluate temperature differences in cells

    PubMed Central

    Lucia, Umberto; Grazzini, Giuseppe; Montrucchio, Bartolomeo; Grisolia, Giulia; Borchiellini, Romano; Gervino, Gianpiero; Castagnoli, Carlotta; Ponzetto, Antonio; Silvagno, Francesca

    2015-01-01

    The aim of this work was to evaluate differences in energy flows between normal and immortalized cells when these distinct biological systems are exposed to environmental stimulation. These differences were considered using a constructal thermodynamic approach, and were subsequently verified experimentally. The application of constructal law to cell analysis led to the conclusion that temperature differences between cells with distinct behaviour can be amplified by interaction between cells and external fields. Experimental validation of the principle was carried out on two cellular models exposed to electromagnetic fields. By infrared thermography we were able to assess small changes in heat dissipation measured as a variation in cell internal energy. The experimental data thus obtained are in agreement with the theoretical calculation, because they show a different thermal dispersion pattern when normal and immortalized cells are exposed to electromagnetic fields. By using two methods that support and validate each other, we have demonstrated that the cell/environment interaction can be exploited to enhance cell behavior differences, in particular heat dissipation. We propose infrared thermography as a technique effective in discriminating distinct patterns of thermal dispersion and therefore able to distinguish a normal phenotype from a transformed one. PMID:26100383

  17. A SEX DIFFERENCE IN THE TEMPERATURE RESPONSE OF RATS TO EXERCISE,

    DTIC Science & Technology

    EXERCISE (PHYSIOLOGY), BODY TEMPERATURE), (*HEAT TOLERANCE, EXERCISE (PHYSIOLOGY)), (*BODY TEMPERATURE, RATS), SEX , SEX GLANDS, OVARIES, PROGESTERONE, TESTOSTERONE, EXCISION, TOLERANCES(PHYSIOLOGY), BLOOD VESSELS, MALES, FEMALES

  18. CMOS-Compatible Room-Temperature Rectifier Toward Terahertz Radiation Detection

    NASA Astrophysics Data System (ADS)

    Varlamava, Volha; De Amicis, Giovanni; Del Monte, Andrea; Perticaroli, Stefano; Rao, Rosario; Palma, Fabrizio

    2016-08-01

    In this paper, we present a new rectifying device, compatible with the technology of CMOS image sensors, suitable for implementing a direct-conversion detector operating at room temperature for operation at up to terahertz frequencies. The rectifying device can be obtained by introducing some simple modifications of the charge-storage well in conventional CMOS integrated circuits, making the proposed solution easy to integrate with the existing imaging systems. The rectifying device is combined with the different elements of the detector, composed of a 3D high-performance antenna and a charge-storage well. In particular, its position just below the edge of the 3D antenna takes maximum advantage of the high electric field concentrated by the antenna itself. In addition, the proposed structure ensures the integrity of the charge-storage well of the detector. In the structure, it is not necessary to use very scaled and costly technological nodes, since the CMOS transistor only provides the necessary integrated readout electronics. On-wafer measurements of RF characteristics of the designed junction are reported and discussed. The overall performances of the entire detector in terms of noise equivalent power (NEP) are evaluated by combining low-frequency measurements of the rectifier with numerical simulations of the 3D antenna and the semiconductor structure at 1 THz, allowing prediction of the achievable NEP.

  19. Evolutionary adaptation to temperature. VIII. Effects of temperature on growth rate in natural isolates of Escherichia coli and Salmonella enterica from different thermal environments.

    PubMed

    Bronikowski, A M; Bennett, A F; Lenski, R E

    2001-01-01

    Are enteric bacteria specifically adapted to the thermal environment of their hosts? In particular, do the optimal temperatures and thermal niches of the bacterial flora reflect seasonal, geographic, or phylogenetic differences in their hosts' temperatures? We examined these questions by measuring the relationship between the temperature-dependent growth rates of enteric bacteria in a free-living ectothermic host. We sampled two species of enteric bacteria (Escherichia coli and Salmonella enterica) from three natural populations of slider turtles (Trachemys scripta elegans) seasonally over two years. Despite pronounced differences in turtle body temperatures at different seasons and in different locations, we found no evidence that the thermal growth profiles of these bacteria mirrored this variation. Optimal temperatures and maximal growth rates in rich medium were nearly the same for both bacterial species (35-36 degrees C, 2.5 doublings per hour). The thermal niche (defined as the range of temperatures over which 75% of maximal growth rate occurred) was slightly higher for E. coli (28.5-41.0 degrees C) than for S. enterica (27.7-39.8 degrees C), but the niche breadth was about the same for both. We also measured the thermal dependence of growth rate in these same bacterial species isolated from mammalian hosts. Both bacterial species had temperatures of maximal growth and thermal niches that were about 2 degrees C higher than those of their respective conspecifics sampled from turtles; niche breadths were not different. These data suggest that these bacterial species are thermal generalists that do not track fine-scale changes in their thermal environments. Even major differences in body temperatures, as great as those between ectothermic and endothermic hosts, may result in the evolution of rather modest changes in thermal properties.

  20. Improving the energy efficiency of refrigeration plants by decreasing the temperature difference in air-cooled condensers

    NASA Astrophysics Data System (ADS)

    Shishov, V. V.; Talyzin, M. S.

    2015-09-01

    The electric energy consumption efficiency is estimated in comparing the real refrigeration machine cycle with the theoretical inverse Carnot cycle. The potential for saving electricity in using aircooled condensers with different values of temperature difference is shown. A procedure for calculating a refrigerating system with the evaporation temperature equal to -10°C, which corresponds at this temperature level to the thermal load of a standard supermarket, is described. The calculation was carried out taking into account the annual profile of temperatures in the indicated locality and based on the possibility of adjusting the condenser capacity for maintaining constant condensation temperature. The payback period in case of using condensers with different values of temperature difference is calculated; for example, in using condensers with a temperature difference of less than 15 K, the payback period will be less than one year. Decreasing the temperature difference results, on one hand, in a larger annual consumption of electric energy by the condenser fans, and on the other hand, it results in a lower condensation pressure, which leads to a smaller annual consumption of energy by the compressor unit. As a result, the total amount of energy consumed by the refrigeration system decreases so that despite a higher cost of condensers designed to operate at lower values of temperature difference, it becomes possible to achieve the above-mentioned payback period. Additionally, the payback period in case of using an air-cooled microchannel aluminum condenser was calculated: in case of using such a condenser with a temperature difference of 8 K instead of the condenser with the temperature difference equal to 15 K, the payback period will be less than half a year. Recommendations for designing new refrigeration systems equipped with air-cooled condensers are given.

  1. Ballistics ordnance gelatine - How different concentrations, temperatures and curing times affect calibration results.

    PubMed

    Maiden, Nicholas R; Fisk, Wesley; Wachsberger, Christian; Byard, Roger W

    2015-08-01

    A study was undertaken to determine whether different concentrations of ordnance gelatine, water types, temperatures and curing times would have an effect on projectile penetration of a gelatine tissue surrogate. Both Federal Bureau of Investigation (FBI) and North Atlantic Treaty Organization (NATO) specified gelatines were compared against the FBI calibration standard. 10% w/w and 20% w/w concentrations of gelatine with Bloom numbers of 250 and 285 were prepared and cured at variable temperatures (3-20°C) for 21 hours-3 weeks. Each block was shot on four occasions on the same range using steel calibre 4.5 mm BBs fired from a Daisy(®) air rifle at the required standard velocity of 180 ± 4.5 m/s, to ascertain the mean penetration depth. The results showed no significant difference in mean penetration depth using the three different water types (p > 0.05). Temperature changes and curing times did affect penetration depth. At 10°C, mean penetration depth with 20% gelatine 285 Bloom for the two water types tested was 49.7 ± 1.5 mm after 21 h curing time, whereas the same formulation at 20°C using two different water types was 79.1 ± 2.1 mm after 100 h curing time (p < 0.001). Neither of the NATO 20% concentrations of gelatine at 10°C or a 20% concentration of 285 Bloom gelatine at 10°C met the same calibration standard as the FBI recommended 10% formulation at 4°C. A 20% concentration of 285 Bloom at 20°C met the same calibration/penetration criteria as a 10% concentration of 250 Bloom at 4 °C after 100 h of curing, therefore matching the FBI calibration standard for a soft tissue simulant for wound ballistics research. These results demonstrate significant variability in simulant properties. Failure to standardise ballistic simulants may invalidate experimental results.

  2. Influence of different maceration time and temperatures on total phenols, colour and sensory properties of Cabernet Sauvignon wines.

    PubMed

    Şener, Hasan; Yildirim, Hatice Kalkan

    2013-12-01

    Maceration and fermentation time and temperatures are important factors affecting wine quality. In this study different maceration times (3 and 6 days) and temperatures (15  and 25 ) during production of red wine (Vitis vinifera L. Cabernet Sauvignon) were investigated. In all wines standard wine chemical parameters and some specific parameters as total phenols, tartaric esters, total flavonols and colour parameters (CD, CI, T, dA%, %Y, %R, %B, CIELAB values) were determined. Sensory evaluation was performed by descriptive sensory analysis. The results demonstrated not only the importance of skin contact time and temperature during maceration but also the effects of transition temperatures (different maceration and fermentation temperatures) on wine quality as a whole. The results of sensory descriptive analyses revealed that the temperature significantly affected the aroma and flavour attributes of wines. The highest scores for 'cassis', 'clove', 'fresh fruity' and 'rose' characters were obtained in wines produced at low temperature (15 ) of maceration (6 days) and fermentation.

  3. Temperature differences are associated with malignancy on lung lesions: a clinical study

    PubMed Central

    Stefanadis, Christodoulos; Chrysohoou, Christina; Panagiotakos, Demosthenes B; Passalidou, Elisabeth; Katsi, Vasiliki; Polychronopoulos, Vlassios; Toutouzas, Pavlos K

    2003-01-01

    Background Although new endoscopic techniques can enhance the ability to detect a suspicious lung lesion, the primary diagnosis still depends on subjective visual assessment. We evaluated whether thermal heterogeneity of solid tumors, in bronchial epithelium, constitutes an additional marker for the diagnosis of benign and malignant lesions. Methods A new method, developed in our institute, is introduced in order to detect temperature in human pulmonary epithelium, in vivo. This method is based on a thermography catheter, which passes the biopsy channel of the fiber optic bronchoscope. We calculated the temperature differences (ΔT) between the lesion and a normal bronchial epithelium area on 22 lesions of 20 subjects, 50 – 65 years old. Results Eleven lesions were benign and 11 were malignant, according to the biopsy histology followed the thermography procedure. We found significant differences of ÄT between patients with benign and malignant tumor (0.71 ± 0.6 vs. 1.23 ± 0.4°C, p < 0.05). Logistic regression analysis showed that 1-Celsius degree differences between normal tissue and suspicious lesion six-fold the probability of malignancy (odds ratio = 6.18, 95% CI 0.89 – 42.7). Also, ΔT values greater than 1.05°C, constitutes a crucial point for the discrimination of malignancy, in bronchial epithelium, with sensitivity (64%) and specificity (91%). Conclusion These findings suggest that the calculated ΔT between normal tissue and a neoplastic area could be a useful criterion for the diagnosis of malignancy in tumors of lung lesions. PMID:12515579

  4. A comparative evaluation of wear of enamel caused by ceramics with different fusion temperatures.

    PubMed

    Khandelwal, Meenakshi; Jain, Deshraj

    2013-12-01

    Dental ceramics are the most used esthetic fixed Prosthodontic restorative material today. However, dentists remain suspicious about their potential abrasivity. Lower-fusing ceramic materials developed, are claimed to be wear friendly. This study was conducted to compare the wear of enamel of extracted teeth against one conventionally used ceramic VMK-95 (fusing temperature 930 °C) and two new lower-fusing ceramics-Omega 900 and Finesse with fusing temperatures 900 and 760 °C respectively, used for metal-ceramic restorations. Metal disks were prepared from ceramic alloy and divided into three groups of 10 disks each on which VMK-95, Omega 900 and Finesse ceramics were applied respectively. Ceramic disks and tooth specimen were mounted on custom-made wear simulator and subjected to predefined masticatory test. Each tooth specimen was profiled by laser triangulation sensor before and after masticatory test. Difference in height was calculated. The results showed that mean loss of height of tooth was least against Finesse (0.3431 + 0.0177 mm) followed by Omega 900 (0.4076 + 0.0135 mm) and VMK-95 (0.6177 + 0.014 mm). Statistical analysis revealed statistically significant difference between VMK-95 & Omega 900 and VMK-95 & Finesse. The difference in loss of height of tooth against Finesse & Omega 900 is statistically insignificant (P < 0.001). The results of this study indicate that lower-fusing dental ceramics cause less wear of opposing enamel.

  5. The Effect of Different Water Immersion Temperatures on Post-Exercise Parasympathetic Reactivation

    PubMed Central

    de Oliveira Ottone, Vinícius; de Castro Magalhães, Flávio; de Paula, Fabrício; Avelar, Núbia Carelli Pereira; Aguiar, Paula Fernandes; da Matta Sampaio, Pâmela Fiche; Duarte, Tamiris Campos; Costa, Karine Beatriz; Araújo, Tatiane Líliam; Coimbra, Cândido Celso; Nakamura, Fábio Yuzo; Amorim, Fabiano Trigueiro; Rocha-Vieira, Etel

    2014-01-01

    Purpose We evaluated the effect of different water immersion (WI) temperatures on post-exercise cardiac parasympathetic reactivation. Methods Eight young, physically active men participated in four experimental conditions composed of resting (REST), exercise session (resistance and endurance exercises), post-exercise recovery strategies, including 15 min of WI at 15°C (CWI), 28°C (TWI), 38°C (HWI) or control (CTRL, seated at room temperature), followed by passive resting. The following indices were assessed before and during WI, 30 min post-WI and 4 hours post-exercise: mean R-R (mR-R), the natural logarithm (ln) of the square root of the mean of the sum of the squares of differences between adjacent normal R–R (ln rMSSD) and the ln of instantaneous beat-to-beat variability (ln SD1). Results The results showed that during WI mRR was reduced for CTRL, TWI and HWI versus REST, and ln rMSSD and ln SD1 were reduced for TWI and HWI versus REST. During post-WI, mRR, ln rMSSD and ln SD1 were reduced for HWI versus REST, and mRR values for CWI were higher versus CTRL. Four hours post exercise, mRR was reduced for HWI versus REST, although no difference was observed among conditions. Conclusions We conclude that CWI accelerates, while HWI blunts post-exercise parasympathetic reactivation, but these recovery strategies are short-lasting and not evident 4 hours after the exercise session. PMID:25437181

  6. Physical properties of biaxially oriented poly(ethylene terephtalate) irradiated at different temperatures and doses with electron beam

    NASA Astrophysics Data System (ADS)

    Adem, E.; Hernández-Sampelayo, A. Rubio; Báez, J. E.; Miranda, J.; Labrada-Delgado, G. J.; Marcos-Fernández, A.

    2017-01-01

    The electron beam irradiation of a biaxially oriented PET film was carried out in air over a range of 50-3000 kGy at different temperatures and a dose rate of 4.48 kGy min-1. The effects of the irradiation at temperatures above and below the glass transition temperature (Tg) on the thermal and mechanical properties were studied. Melting temperature decreased slightly and crystallization temperature and crystallinity increased significantly with the increase in dose, more at higher irradiation temperature, whereas Tg did not show any significant change with dose or temperature. Mechanical properties were adversely affected by irradiation. Stress and strain at break were strongly reduced, more at higher irradiation temperature, and Young's Modulus slightly increased with the increase in dose. The changes in properties were related to the chain scission produced by the electron beam irradiation leading to a decrease in molecular weight.

  7. Entransia and Hormidiella, sister lineages of Klebsormidium (Streptophyta), respond differently to light, temperature, and desiccation stress.

    PubMed

    Herburger, Klaus; Karsten, Ulf; Holzinger, Andreas

    2016-09-01

    The green-algal class Klebsormidiophyceae (Streptophyta), which occurs worldwide, comprises the genera Klebsormidium, Interfilum, Entransia, and Hormidiella. Ecophysiological research has so far focused on the first two genera because they are abundant in biological soil crust communities. The present study investigated the photosynthetic performances of Hormidiella attenuata and two strains of Entransia fimbriata under light, temperature, and desiccation stress. Their ultrastructure was compared using transmission electron microscopy. The two Entransia strains showed similar physiological responses. They used light more efficiently than Hormidiella, as indicated by higher oxygen production and relative electron transport rate under low light conditions, lower light saturation and compensation points, and higher maximum oxygen production during light saturation. Their requirement for low light levels explains the restriction of Entransia to dim limnetic habitats. In contrast, Hormidiella, which prefers drier soil habitats, responded to light gradients similarly to other aero-terrestrial green algae. Compared to Entransia, Hormidiella was less affected by short-term desiccation, and rehydration allowed full recovery of the photosynthetic performance. Nevertheless, both strains of Entransia coped with low water availability better than other freshwater algae. Photosynthetic oxygen production in relation to respiratory consumption was higher in low temperatures (Entransia: 5 °C, Hormidiella: 10 °C) and the ratio decreased with increasing temperatures. Hormidiella exhibited conspicuous triangular spaces in the cell wall corners, which were filled either with undulating cell wall material or with various inclusions. These structures are commonly seen in various members of Klebsormidiophyceae. The data revealed significant differences between Hormidiella and Entransia, but appropriate adaptations to their respective habitats.

  8. Anaerobic oxidation of methane at different temperature regimes in Guaymas Basin hydrothermal sediments.

    PubMed

    Biddle, Jennifer F; Cardman, Zena; Mendlovitz, Howard; Albert, Daniel B; Lloyd, Karen G; Boetius, Antje; Teske, Andreas

    2012-05-01

    Anaerobic oxidation of methane (AOM) was investigated in hydrothermal sediments of Guaymas Basin based on δ(13)C signatures of CH(4), dissolved inorganic carbon and porewater concentration profiles of CH(4) and sulfate. Cool, warm and hot in-situ temperature regimes (15-20 °C, 30-35 °C and 70-95 °C) were selected from hydrothermal locations in Guaymas Basin to compare AOM geochemistry and 16S ribosomal RNA (rRNA), mcrA and dsrAB genes of the microbial communities. 16S rRNA gene clone libraries from the cool and hot AOM cores yielded similar archaeal types such as Miscellaneous Crenarchaeotal Group, Thermoproteales and anaerobic methane-oxidizing archaea (ANME)-1; some of the ANME-1 archaea formed a separate 16S rRNA lineage that at present seems to be limited to Guaymas Basin. Congruent results were obtained by mcrA gene analysis. The warm AOM core, chemically distinct by lower porewater sulfide concentrations, hosted a different archaeal community dominated by the two deep subsurface archaeal lineages Marine Benthic Group D and Marine Benthic Group B, and by members of the Methanosarcinales including ANME-2 archaea. This distinct composition of the methane-cycling archaeal community in the warm AOM core was confirmed by mcrA gene analysis. Functional genes of sulfate-reducing bacteria and archaea, dsrAB, showed more overlap between all cores, regardless of the core temperature. 16S rRNA gene clone libraries with Euryarchaeota-specific primers detected members of the Archaeoglobus clade in the cool and hot cores. A V6-tag high-throughput sequencing survey generally supported the clone library results while providing high-resolution detail on archaeal and bacterial community structure. These results indicate that AOM and the responsible archaeal communities persist over a wide temperature range.

  9. Universal predictive models on octanol-air partition coefficients at different temperatures for persistent organic pollutants.

    PubMed

    Chen, Jingwen; Harner, Tom; Ding, Guanghui; Quan, Xie; Schramm, Karl-Werner; Kettrup, Antonius

    2004-10-01

    Owing to the importance of octanol-air partition coefficients (KOA) in describing the partition of organic pollutants from air to environmental organic phases, the paucity of KOA data at different environmental temperatures, and the difficulty or high expenditures involved in experimental determination, the development of predictive models for KOA is necessary. Approaches such as this are greatly needed to evaluate the environmental fate of the ever-increasing list of production chemicals. Partial least squares (PLS) regression with 18 molecular structural descriptors was used to develop predictive models based on directly measured KOA values of selected chlorobenzenes, polychlorinated biphenyls (PCBs), polychlorinated naphthalenes, polychlorinated dibenzo-p-dioxins/dibenzofurans, polybrominated diphenyl ethers, polycyclic aromatic hydrocarbons, and organochlorine pesticides (OPs). An optimization procedure resulted in two temperature-dependent universal predictive models that explained at least 91 % of the variance of log KOA. Model 1 was the more general of the two models that could be used for all the persistent organic pollutant (POP) classes investigated. Although model 1 performed poorly for select OPs, this was attributed to wide variability in structural types within this subset of POPs and their diversity compared to the other POP classes that were investigated. The exclusion of the structurally complex OP subset resulted in a more precise model, model 5. Intermolecular dispersive interactions (induced dipole-induced dipole forces) between octanol and solute molecules play a decisive role in governing KOA and its temperature dependence. Further investigations are needed to better characterize the steric structures of the POPs under study, especially of OPs.

  10. Porosity of UHPFRC exposed to high temperatures determined by different techniques

    NASA Astrophysics Data System (ADS)

    Korecký, Tomáš; Pokorný, Jaroslav; Fořt, Jan; Čítek, David; Pavlík, Zbyšek

    2016-07-01

    The pore system characterization of an Ultra High Performance Fibre Reinforced Concrete (UHPFRC) exposed to the elevated temperatures is presented in the paper. The porosity and pore size distribution of building materials are of the particular importance because of their clear effect on durability and service life of structural elements and buildings. Material characteristics as mechanical, thermal and hygric properties are strongly dependent on pore system. For porosity measurement, several techniques having specific advantages or disadvantages with respect to the pore size are available. In building materials research, usage of Mercury Intrusion Porosimetry (MIP) with range of the detected pores up to 100 µm is the most common. Nevertheless, in practical measurements, the differences between the porosity values determined by helium pycnometry and MIP are usually observed. It can be attributed to the presence of pores bigger than 100 µm. Based on the literature analysis it is evident that the porosity increases with the amount of fibres used since fibres application reduces workability of fresh mixture and thus cause heterogeneities and microcavities in material microstructure and interfacial transition zone between fibres, aggregates and cement paste. Therefore, the Optical Porosimetry (OP) based on an image analysis is presented in the paper as a suitable supplemental method for classification number, size and shape of bigger pores. At first, porosity is investigated on samples without temperature loading. Then, on samples which are exposed to the temperatures of 400, 800, and 1000 °C respectively. Pores size distribution is studied using mercury intrusion porosimeters Pascal 140 and 440. Images are captured by an optical microscope with an attached digital camera. The obtained results show necessity to apply the combined technique for the assessment of the porosity value.

  11. Effects of origin, seasons and storage under different temperatures on germination of Senecio vulgaris (Asteraceae) seeds

    PubMed Central

    2016-01-01

    Invasive plants colonize new environments, become pests and cause biodiversity loss, economic loss and health damage. Senecio vulgaris L. (Common groundsel, Asteraceae), a widely distributing cosmopolitan weed in the temperate area, is reported with large populations in the north–eastern and south–western part, but not in southern, central, or north-western parts of China. We studied the germination behavior of S. vulgaris to explain the distribution and the biological invasion of this species in China. We used seeds originating from six native and six invasive populations to conduct germination experiments in a climate chamber and under outdoor condition. When incubated in a climate chamber (15 °C), seeds from the majority of the populations showed >90% germination percentage (GP) and the GP was equal for seeds with a native and invasive origin. The mean germination time (MGT) was significantly different among the populations. Under outdoor conditions, significant effects of origin, storage conditions (stored at 4 °C or ambient room temperature, ca. 27 °C) and seasons (in summer or autumn) were observed on the GP while the MGT was only affected by the season. In autumn, the GP (38.6%) was higher and the MGT was slightly longer than that in summer. In autumn, seeds stored at 4 °C showed higher GP than those stored at ambient room temperature (ca.27 °C), and seeds from invasive populations revealed higher GP than those from native populations. The results implied that the high temperature in summer has a negative impact on the germination and might cause viability loss or secondary dormancy to S. vulgaris seeds. Our study offers a clue to exploring what factor limits the distribution of S. vulgaris in China by explaining why, in the cities in South-East China and central China such as Wuhan, S. vulgaris cannot establish natural and viable populations. PMID:27602303

  12. Effects of origin, seasons and storage under different temperatures on germination of Senecio vulgaris (Asteraceae) seeds.

    PubMed

    Ndihokubwayo, Noel; Nguyen, Viet-Thang; Cheng, Dandan

    2016-01-01

    Invasive plants colonize new environments, become pests and cause biodiversity loss, economic loss and health damage. Senecio vulgaris L. (Common groundsel, Asteraceae), a widely distributing cosmopolitan weed in the temperate area, is reported with large populations in the north-eastern and south-western part, but not in southern, central, or north-western parts of China. We studied the germination behavior of S. vulgaris to explain the distribution and the biological invasion of this species in China. We used seeds originating from six native and six invasive populations to conduct germination experiments in a climate chamber and under outdoor condition. When incubated in a climate chamber (15 °C), seeds from the majority of the populations showed >90% germination percentage (GP) and the GP was equal for seeds with a native and invasive origin. The mean germination time (MGT) was significantly different among the populations. Under outdoor conditions, significant effects of origin, storage conditions (stored at 4 °C or ambient room temperature, ca. 27 °C) and seasons (in summer or autumn) were observed on the GP while the MGT was only affected by the season. In autumn, the GP (38.6%) was higher and the MGT was slightly longer than that in summer. In autumn, seeds stored at 4 °C showed higher GP than those stored at ambient room temperature (ca.27 °C), and seeds from invasive populations revealed higher GP than those from native populations. The results implied that the high temperature in summer has a negative impact on the germination and might cause viability loss or secondary dormancy to S. vulgaris seeds. Our study offers a clue to exploring what factor limits the distribution of S. vulgaris in China by explaining why, in the cities in South-East China and central China such as Wuhan, S. vulgaris cannot establish natural and viable populations.

  13. Muscle fatigue examined at different temperatures in experiments on intact mammalian (rat) muscle fibers

    PubMed Central

    Roots, H.; Ball, G.; Talbot-Ponsonby, J.; King, M.; McBeath, K.; Ranatunga, K. W.

    2009-01-01

    In experiments on small bundles of intact fibers from a rat fast muscle, in vitro, we examined the decline in force in repeated tetanic contractions; the aim was to characterize the effect of shortening and of temperature on the initial phase of muscle fatigue. Short tetanic contractions were elicited at a control repetition rate of 1/60 s, and fatigue was induced by raising the rate to 1/5 s for 2–3 min, both in isometric mode (no shortening) and in shortening mode, in which each tetanic contraction included a ramp shortening at a standard velocity. In experiments at 20°C (n = 12), the force decline during a fatigue run was 25% in the isometric mode but was significantly higher (35%) in the shortening mode. In experiments at different temperatures (10–30°C, n = 11), the tetanic frequency and duration were adjusted as appropriate, and for shortening mode, the velocity was adjusted for maximum power output. In isometric mode, fatigue of force was significantly less at 30°C (∼20%) than at 10°C (∼30%); the power output (force × velocity) was >10× higher at 30°C than at 10°C, and power decline during a fatigue run was less at 30°C (∼20–30%) than at 10°C (∼50%). The finding that the extent of fatigue is increased with shortening contractions and is lower at higher temperatures is consistent with the view that force depression by inorganic phosphate, which accumulates within fibers during activity, may be a primary cause of initial muscle fatigue. PMID:19057001

  14. Response of photosynthetic apparatus to moderate high temperature in contrasting wheat cultivars at different oxygen concentrations.

    PubMed

    Stasik, Oleg; Jones, Hamlyn G

    2007-01-01

    The photosynthetic responses to moderately high temperatures (38 degrees C, imposed at 21% or 2% O(2) in air and 1500 mumol m(-2) s(-1)) were compared in wheat (Triticum aestivum L.) cultivars grown in northern regions of Ukraine and expected to be relatively sensitive to high temperatures ('North' cultivars) and in cultivars grown in southern regions and expected to be relatively heat-tolerant ('South' cultivars). Heating intact leaves in 21% O(2) for 1 h decreased CO(2) assimilation by c. 63% in 'North' cultivars and only c. 32% in 'South' cultivars, with a decrease in PSII activity being observed in only one of the 'North' cultivars. Carboxylation efficiency was decreased by about 2.7-fold in 'North' cultivars with no significant effect in 'South' cultivars. The maximum rates of carboxylation by Rubisco in vivo, V(cmax), estimated from Farquhar's model, increased more than 2-fold in 'South' cultivars and remained unchanged in 'North' cultivars while the maximum rate of RuBP regeneration, J(max), decreased by 53% and 21% in 'North' and 'South' cultivars, respectively. Where the heat treatment was imposed in 2% O(2) this increased (as compared with treatment at 21% O(2)) the inhibitory effect on CO(2) assimilation in tolerant cultivars, but decreased it in sensitive ones. The results suggested that differences in tolerance of moderately high temperatures in wheat relate to the stability of the Rubisco function and to RuBP regeneration activity rather than to the effects on PSII activity or stomatal control.

  15. The time of day differently influences fatigue and locomotor activity: is body temperature a key factor?

    PubMed

    Machado, Frederico Sander Mansur; Rodovalho, Gisele Vieira; Coimbra, Cândido Celso

    2015-03-01

    The aim of this study was to verify the possible interactions between exercise capacity and spontaneous locomotor activity (SLA) during the oscillation of core body temperature (Tb) that occurs during the light/dark cycle. Wistar rats (n=11) were kept at an animal facility under a light/dark cycle of 14/10h at an ambient temperature of 23°C and water and food ad libitum. Initially, in order to characterize the daily oscillation in SLA and Tb of the rats, these parameters were continuously recorded for 24h using an implantable telemetric sensor (G2 E-Mitter). The animals were randomly assigned to two progressive exercise test protocols until fatigue during the beginning of light and dark-phases. Fatigue was defined as the moment rats could not keep pace with the treadmill. We assessed the time to fatigue, workload and Tb changes induced by exercise. Each test was separated by 3days. Our results showed that exercise capacity and heat storage were higher during the light-phase (p<0.05). In contrast, we observed that both SLA and Tb were higher during the dark-phase (p<0.01). Notably, the correlation analysis between the amount of SLA and the running capacity observed at each phase of the daily cycle revealed that, regardless of the time of the day, both types of locomotor physical activity have an important inherent component (r=0.864 and r=0.784, respectively, p<0.01) without a direct relationship between them. This finding provides further support for the existence of specific control mechanisms for each type of physical activity. In conclusion, our data indicate that the relationship between the body temperature and different types of physical activity might be affected by the light/dark cycle. These results mean that, although exercise performance and spontaneous locomotor activity are not directly associated, both are strongly influenced by daily cycles of light and dark.

  16. Acute toxicity of arsenic under different temperatures and salinity conditions on the white shrimp Litopenaeus vannamei.

    PubMed

    Valentino-Álvarez, Jesús Alberto; Núñez-Nogueira, Gabriel; Fernández-Bringas, Laura

    2013-06-01

    The aim of this study was to determine acute toxicity in the post larvae of the white shrimp Litopenaeus vannamei after 96 h of exposure to dissolved arsenic under three different temperatures and salinity conditions. Recent reports have shown an increase in the presence of this metalloid in coastal waters, estuaries, and lagoons along the Mexican coast. The white shrimp stands out for its adaptability to temperature and salinity changes and for being the main product for many commercial fisheries; it has the highest volume of oceanic capture and production in Mexican shrimp farms. Lethal concentrations (LC50-96 h) were obtained at nine different combinations (3 × 3 combinations in total) of temperature (20, 25, and 30 °C) and salinity (17, 25, and 33) showing mean LC50-96 h values (±standard error) of 9.13 ± 0.76, 9.17 ± 0.56, and 6.23 ± 0.57 mgAs L(-1)(at 20 °C and 17, 25, and 33 salinity); 12.29 ± 2.09, 8.70 ± 0.82, and 8.03 ± 0.59 mgAs L(-1) (at 25 °C and 17, 25, and 33 salinity); and 7.84 ± 1.30, 8.49 ± 1.40, and 7.54 ± 0.51 mgAs L(-1) (at 30 °C and 17, 25, and 33 salinity), respectively. No significant differences were observed for the optimal temperature and isosmotic point of maintenance (25 °C-S 25) for the species, with respect to the other experimental conditions tested, except for at 20 °C-S 33, which was the most toxic. Toxicity under 20 °C-S 33 conditions was also higher than 25 °C-S 17 and 20 °C (S 17 or 25). The least toxic condition was 25 °C-S 17. All this suggests that the toxic effect of arsenic is not affected by temperature changes; it depends on the osmoregulatory pattern developed by the shrimp, either hyperosmotic at low salinity or hiposmotic at high salinity, as observed at least on the extreme salinity conditions here tested (17 and 33). However, further studies testing salinities near the isosmotic point (between 20 and 30 salinities) are needed to

  17. Predictive modeling of Pseudomonas fluorescens growth under different temperature and pH values.

    PubMed

    Gonçalves, Letícia Dias Dos Anjos; Piccoli, Roberta Hilsdorf; Peres, Alexandre de Paula; Saúde, André Vital

    Meat is one of the most perishable foods owing to its nutrient availability, high water activity, and pH around 5.6. These properties are highly conducive for microbial growth. Fresh meat, when exposed to oxygen, is subjected to the action of aerobic psychrotrophic, proteolytic, and lipolytic spoilage microorganisms, such as Pseudomonas spp. The spoilage results in the appearance of slime and off-flavor in food. In order to predict the growth of Pseudomonas fluorescens in fresh meat at different pH values, stored under refrigeration, and temperature abuse, microbial mathematical modeling was applied. The primary Baranyi and Roberts and the modified Gompertz models were fitted to the experimental data to obtain the growth parameters. The Ratkowsky extended model was used to determine the effect of pH and temperature on the growth parameter μmax. The program DMFit 3.0 was used for model adjustment and fitting. The experimental data showed good fit for both the models tested, and the primary and secondary models based on the Baranyi and Roberts models showed better validation. Thus, these models can be applied to predict the growth of P. fluorescens under the conditions tested.

  18. Changes in the quality of superchilled rabbit meat stored at different temperatures.

    PubMed

    Lan, Yang; Shang, Yongbiao; Song, Ying; Dong, Quan

    2016-07-01

    This work studied the effects of a superchilling process at two different temperatures on the shelf life and selected quality parameters of rabbit meat. As the storage time increased, the rates at which the total aerobic count, total volatile basic nitrogen, thiobarbituric acid-reactive substances and pH value increased were significantly lower in superchilled rabbit meat stored at -4°C compared to those in rabbit meat stored at -2.5°C and 4°C. SDS-PAGE analysis indicated that the decrease in storage temperature could significantly reduce the degree of protein degradation. The lightness, redness, shear force, the integrity of muscle microstructure and water holding capacity decreased with increasing storage time. Compared with the samples frozen at -18°C, superchilled rabbit meat shows a marked reduction in microstructure deterioration. These results suggest that shelf life of good-quality rabbit meat was 20d under superchilling at -2.5°C and at least 36d under superchilling at -4°C, compared with less than 6d under traditional chilled storage.

  19. Composition and temperature-induced structural changes in lead-tellurite glasses on different length scales.

    PubMed

    Chakraborty, S; Arora, A K; Sivasubramanian, V; Krishna, P S R; Krishnan, R Venkata

    2012-12-19

    Processes occurring at macroscopic and microscopic length scales across the glass transition (T(g)) in lead-tellurite glass (PbO)(x)(TeO(2))(1-x) (x = 0.1-0.3) are investigated using Brillouin and Raman spectroscopy, respectively. For all the samples, the temperature dependence of the longitudinal acoustic (LA) mode is found to exhibit a universal scaling below T(g) and a rapid softening above T(g). The lower value of elastic modulus at a higher concentration of network modifier PbO, estimated from Brillouin data, arises due to loss of network rigidity. From quantitative analysis of the reduced Raman spectra, several modes are found to exhibit anomalous changes across T(g). Instead of the expected anharmonic behaviour, several modes exhibit hardening, suggesting stiffening of the stretching force constants with temperature, the effect being more pronounced in glasses with higher x. In addition, incorporation of PbO in the glass is also found to narrow down the bond-length distribution, as evident from the sharpening of the Raman bands. The stiffening of the force constants of molecular units at a microscopic length scale and the decrease of elastic constant attributed to loss of network rigidity on a macroscopic length scale appear to be opposite. These different behaviours at two length scales are understood on the basis of a microscopic model involving TeO(n) and PbO units in the structure.

  20. Germination of Croton urucurana L. seeds exposed to different storage temperatures and pre-germinative treatments.

    PubMed

    Scalon, Silvana P Q; Mussury, Rosilda M; Lima, Andréa A

    2012-03-01

    The present work evaluated the germinability and vigor of Croton urucurana seeds. 1) Seeds were sorted by color (caramel, gray and black) and were subjected to seven different pre-germination treatments followed by incubation at 20ºC, 25°C or 20/30°C. 2) Seeds were stored in cold chambers or at room temperature for up to 300 days and were subsequently incubated at 20/30ºC in a germination chamber or under greenhouse conditions. Only gray seeds showed significant germination rates. The highest first count percentages of total germination and the highest germination speed indices were observed in control seeds and in those which were treated with water or 200 mg.L(-1) gibberellic acid for 12 hours. Seeds stored under refrigeration showed the highest values for all of the characteristics examined, as well as less electrical conductivity of the imbibing solution. Seedlings were more vigorous when seeds were stored for 300 days in a cold chamber. The seedlings production can be increased by incubating the seeds at alternating temperatures (20/30°C). The seeds do not need pre-germination treatments.

  1. Characterisation of silica derived from rice husk (Muar, Johor, Malaysia) decomposition at different temperatures

    NASA Astrophysics Data System (ADS)

    Azmi, M. A.; Ismail, N. A. A.; Rizamarhaiza, M.; W. M. Hasif. A. A., K.; Taib, H.

    2016-07-01

    Rice husk was thermally decomposed to yield powder composed of silica (SiO2). Temperatures of 700°C and 1000°C were chosen as the decomposition temperatures. X-Ray Diffraction (XRD), X-Ray Florescence (XRF), Fourier Transform Infrared (FTIR), and Field Emission Scanning Electron Microscope (FESEM) analyses were conducted on a synthetic silica powder (SS-SiO2) and the rice husk ash as for the comparative characterisation study. XRD analyses clearly indicated that the decomposed rice husk yielded silica of different nature which are Crystalline Rice Husk Silica (C-RHSiO2) and Amorphous Rice Husk Silica (A-RHSiO2). Moreover, it was found that SS-SiO2 was of Quartz phase, C-RHSiO2 was of Trydimite and Cristobalite. Through XRF detection, the highest SiO2 purity was detected in SS-SiO2 followed by C-RHSiO2 and A-RHSiO2 with purity percentages of 99.60%, 82.30% and 86.30% respectively. FTIR results clearly indicated silica (SiO2) bonding 1056, 1064, 1047, 777, 790 and 798 cm-1) increased as the crystallinity silica increased. The Cristobalite phase was detected in C-RH SiO2 at the wavelength of 620 cm-1. Morphological features as observed by FESEM analyses confirmed that, SS-SiO2 and C-RH SiO2 showed prominent coarse granular morphology.

  2. Comparison of three different thermometers in evaluating the body temperature of healthy young adult individuals.

    PubMed

    Basak, Tulay; Aciksoz, Semra; Tosun, Betul; Akyuz, Aygul; Acikel, Cengizhan

    2013-10-01

    The aim of this study was to compare the measurement values obtained with a non-contact infrared thermometer, a tympanic thermometer and a chemical dot thermometer. The research population was composed of students studying in two departments of a university in Ankara. A total of 452 students who fit the inclusion criteria of the study and volunteered to participate were included in the sample. Body temperature measurements with different thermometers were performed by the same researcher at the same room temperature. Data were analyzed in a computerized environment by SPSS 15.0 statistical program pack and Bland-Altman graph. Mean age of healthy young adults participating in the study was 19.66 ± 0.94, and 55.1% of them were female. The agreement limits for non-contact infrared and chemical dot was between -1.30 and 0.32°C; for non-contact infrared and tympanic was between -1.26 and 0.13°C; and for chemical dot and tympanic -0.89 and 0.74°C. It was determined that, although the measurement values of the tympanic membrane and chemical dot thermometers conformed with each other, the conformity of the non-contact infrared thermometer was weak.

  3. Gene and Protein Expression in Response to Different Growth Temperatures and Oxygen Availability in Burkholderia thailandensis

    PubMed Central

    Peano, Clelia; Chiaramonte, Fabrizio; Motta, Sara; Pietrelli, Alessandro; Jaillon, Sebastien; Rossi, Elio; Consolandi, Clarissa; Champion, Olivia L.; Michell, Stephen L.; Freddi, Luca; Falciola, Luigi; Basilico, Fabrizio; Garlanda, Cecilia; Mauri, Pierluigi; De Bellis, Gianluca; Landini, Paolo

    2014-01-01

    Burkholderia thailandensis, although normally avirulent for mammals, can infect macrophages in vitro and has occasionally been reported to cause pneumonia in humans. It is therefore used as a model organism for the human pathogen B. pseudomallei, to which it is closely related phylogenetically. We characterized the B. thailandensis clinical isolate CDC2721121 (BtCDC272) at the genome level and studied its response to environmental cues associated with human host colonization, namely, temperature and oxygen limitation. Effects of the different growth conditions on BtCDC272 were studied through whole genome transcription studies and analysis of proteins associated with the bacterial cell surface. We found that growth at 37°C, compared to 28°C, negatively affected cell motility and flagella production through a mechanism involving regulation of the flagellin-encoding fliC gene at the mRNA stability level. Growth in oxygen-limiting conditions, in contrast, stimulated various processes linked to virulence, such as lipopolysaccharide production and expression of genes encoding protein secretion systems. Consistent with these observations, BtCDC272 grown in oxygen limitation was more resistant to phagocytosis and strongly induced the production of inflammatory cytokines from murine macrophages. Our results suggest that, while temperature sensing is important for regulation of B. thailandensis cell motility, oxygen limitation has a deeper impact on its physiology and constitutes a crucial environmental signal for the production of virulence factors. PMID:24671187

  4. The influence of internal and skin temperatures on active cutaneous vasodilation under different levels of exercise and ambient temperatures in humans.

    PubMed

    Demachi, Koichi; Yoshida, Tetsuya; Kume, Masashi; Tsuji, Michio; Tsuneoka, Hideyuki

    2013-07-01

    To clarify the influence of internal and skin temperature on the active cutaneous vasodilation during exercise, the body temperature thresholds for the onset of active vasodilation during light or moderate exercise under different ambient temperature conditions were compared. Seven male subjects performed 30 min of a cycling exercise at 20 % or 50 % of peak oxygen uptake in a room maintained at 20, 24, or 28 °C. Esophageal (Tes) and mean skin temperature (Tsk) as measured by a thermocouple, deep thigh temperature (Tdt) by the zero-heat-flow (ZHF) method, and forearm skin blood flow by laser-Doppler flowmetry (LDF) were monitored. The mean arterial pressure (MAP) was also monitored non-invasively, and the cutaneous vascular conductance (CVC) was calculated as the LDF/MAP. Throughout the experiment, the Tsk at ambient temperatures of 20, 24, and 28 °C were approximately 30, 32, and 34 °C, respectively, for both 20 % and 50 % exercise. During 50 % exercise, the Tes or Tdt thresholds for the onset of the increase in CVC were observed to be similar among the 20, 24, and 28 °C ambient conditions. During 20 % exercise, the increase in Tes and Tdt was significantly lower than those found at 50 %, and the onset of the increase in CVC was only observed at 28 °C. These results suggest that the onset of active vasodilation was affected more strongly by the internal or exercising tissue temperatures than by the skin temperatures during exercise performed at a moderate load in comparison to a light load under Tsk variations ranging from 30 °C to 34 °C. Therefore, the modification by skin temperature of the central control on cutaneous vasomotor tone during exercise may differ between different exercise loads.

  5. The influence of internal and skin temperatures on active cutaneous vasodilation under different levels of exercise and ambient temperatures in humans

    NASA Astrophysics Data System (ADS)

    Demachi, Koichi; Yoshida, Tetsuya; Kume, Masashi; Tsuji, Michio; Tsuneoka, Hideyuki

    2013-07-01

    To clarify the influence of internal and skin temperature on the active cutaneous vasodilation during exercise, the body temperature thresholds for the onset of active vasodilation during light or moderate exercise under different ambient temperature conditions were compared. Seven male subjects performed 30 min of a cycling exercise at 20 % or 50 % of peak oxygen uptake in a room maintained at 20, 24, or 28 °C. Esophageal (Tes) and mean skin temperature (Tsk) as measured by a thermocouple, deep thigh temperature (Tdt) by the zero-heat-flow (ZHF) method, and forearm skin blood flow by laser-Doppler flowmetry (LDF) were monitored. The mean arterial pressure (MAP) was also monitored non-invasively, and the cutaneous vascular conductance (CVC) was calculated as the LDF/MAP. Throughout the experiment, the Tsk at ambient temperatures of 20, 24, and 28 °C were approximately 30, 32, and 34 °C, respectively, for both 20 % and 50 % exercise. During 50 % exercise, the Tes or Tdt thresholds for the onset of the increase in CVC were observed to be similar among the 20, 24, and 28 °C ambient conditions. During 20 % exercise, the increase in Tes and Tdt was significantly lower than those found at 50 %, and the onset of the increase in CVC was only observed at 28 °C. These results suggest that the onset of active vasodilation was affected more strongly by the internal or exercising tissue temperatures than by the skin temperatures during exercise performed at a moderate load in comparison to a light load under Tsk variations ranging from 30 °C to 34 °C. Therefore, the modification by skin temperature of the central control on cutaneous vasomotor tone during exercise may differ between different exercise loads.

  6. Determination of spectrum and different temperature of spontaneous chemiluminescence in rice seeds during early imbibition

    NASA Astrophysics Data System (ADS)

    Chen, WenLi; Xing, Da; Van Wijk, Roeland

    2005-02-01

    With high-sensitivity single-photon counter, spontaneous chemiluminescence (CL) spectrum and different temperature study on rice (Oryza sativa L.) seeds during early imbibition were carried out. The emission spectrum of whole rice seed, rice and coat had a greater proportion of red light during early imbibition. Comparing with spontaneous CL of barley (Hordeum vulgare L.) and soybean (Glycine max L. Merr) seeds, the spontaneous CL of rice seeds had a nonlinear, logarithmic-like increase of intensity in the T range 30-50°C, the Van't Hoff coefficient Q10=IT+10/IT is equal to 2, which led us to the conclusion that spontaneous CL of rice seed during early imbibition partly came from enzyme catalyzing chemistry reaction.

  7. Absorption, Fluorescence and Emission Anisotropy Spectra of 4-Cyano-N,N-dimethylaniline in Different Media and at Different Temperatures

    NASA Astrophysics Data System (ADS)

    Kawski, A.; Piszczek, G.

    1997-05-01

    The effect of temperature on fluorescence and emission anisotropy spectra of 4-cyano-N,N-dimethylaniline (CDMA) was investigated in viscous (glycerol and paraffin oil) and rigid (polyvinyl alcohol) PVA and polyvinyl chloride) PVC) media. A strong effect of temperature on the intensity of a and b emission bands was observed. It was also found that the emission anisotropy, r, does not vary in the longwave emission band a at a fixed temperature but decreases in the emission band b together with the decreasing wavelength. The latter effect is due to the fact that the transition moment in this band is perpendicular to the long axis of the CDMA molecule. For CDMA in paraffin oil, a normal b band with negative emission anisotropy only occurs. In all other media used, the emission anisotropy has lower values, approaching zero, which results from the considerable covering of band b with a broad emission band a.

  8. Calibration of the physiological equivalent temperature index for three different climatic regions

    NASA Astrophysics Data System (ADS)

    Krüger, E.; Rossi, F.; Drach, P.

    2017-02-01

    In human biometeorology, the integration of several microclimatic variables as a combined index facilitates the understanding of how users perceive thermal environments. Indices, such as the physiological equivalent temperature (PET) index, translate the combined effects of meteorological variables on humans in terms of thermal stress or comfort and serve as important aids to climate-responsive urban and regional planning as well as heat stress and thermal comfort analyses. However, there is a need for adjusting proposed comfort/stress ranges of a given index when using it in different climatic contexts. The purpose of this study is to present a preliminary calibration procedure for the PET index for three different climatic regions: Curitiba, Brazil, a subtropical location; Rio de Janeiro, Brazil, a tropical city; and Glasgow, UK, a high-latitude location. Field studies have been carried out by the authors according to a similar protocol and using similar equipment, yielding actual thermal sensation votes and microclimate data, post-processed as PET data. The calibration procedure uses exclusively thermal sensation data as reported by pedestrians during outdoor comfort campaigns and concurrent microclimatic data recorded during the interviews. PET comfort/stress classes differ among the three locations and, in general, are less restrictive as in the original ranges proposed by the index developers.

  9. Bactericidal Effects against S. aureus and Physicochemical Properties of Plasma Activated Water stored at different temperatures

    PubMed Central

    Shen, Jin; Tian, Ying; Li, Yinglong; Ma, Ruonan; Zhang, Qian; Zhang, Jue; Fang, Jing

    2016-01-01

    Water activated by non-thermal plasma creates an acidified solution containing reactive oxygen and nitrogen species, known as plasma-activated water (PAW). The objective of this study was to investigate the effects of different storage temperatures (25 °C, 4 °C, −20 °C, −80 °C) on bactericidal activities against S. aureus and physicochemical properties of PAW up to 30 days. Interestingly, PAW stored at −80 °C yielded the best antibacterial activity against Staphylococcus aureus, 3~4 log reduction over a 30-day period after PAW generation; meanwhile, PAW stored at 25 °C, 4 °C, and −20 °C, respectively, yielded 0.2~2 log decrease in cell viability after the same exposure and storage time. These results were verified by scanning electron microscope (SEM). The physicochemical properties of PAW stored at different temperatures were evaluated, including pH, oxidation reduction potential (ORP), and hydrogen peroxide, nitrate, nitrite anion and NO radical levels. These findings suggested that bacterial activity of PAW stored at 25 °C, 4 °C, −20 °C decreased over time, and depended on three germicidal factors, specifically ORP, H2O2, and NO3−. Moreover, PAW stored at −80 °C retained bactericidal activity, with NO2− contributing to bactericidal ability in association with H2O2. Our findings provide a basis for PAW storage and practical applications in disinfection and food preservation. PMID:27346695

  10. Bactericidal Effects against S. aureus and Physicochemical Properties of Plasma Activated Water stored at different temperatures

    NASA Astrophysics Data System (ADS)

    Shen, Jin; Tian, Ying; Li, Yinglong; Ma, Ruonan; Zhang, Qian; Zhang, Jue; Fang, Jing

    2016-06-01

    Water activated by non-thermal plasma creates an acidified solution containing reactive oxygen and nitrogen species, known as plasma-activated water (PAW). The objective of this study was to investigate the effects of different storage temperatures (25 °C, 4 °C, ‑20 °C, ‑80 °C) on bactericidal activities against S. aureus and physicochemical properties of PAW up to 30 days. Interestingly, PAW stored at ‑80 °C yielded the best antibacterial activity against Staphylococcus aureus, 3~4 log reduction over a 30-day period after PAW generation; meanwhile, PAW stored at 25 °C, 4 °C, and ‑20 °C, respectively, yielded 0.2~2 log decrease in cell viability after the same exposure and storage time. These results were verified by scanning electron microscope (SEM). The physicochemical properties of PAW stored at different temperatures were evaluated, including pH, oxidation reduction potential (ORP), and hydrogen peroxide, nitrate, nitrite anion and NO radical levels. These findings suggested that bacterial activity of PAW stored at 25 °C, 4 °C, ‑20 °C decreased over time, and depended on three germicidal factors, specifically ORP, H2O2, and NO3‑. Moreover, PAW stored at ‑80 °C retained bactericidal activity, with NO2‑ contributing to bactericidal ability in association with H2O2. Our findings provide a basis for PAW storage and practical applications in disinfection and food preservation.

  11. Different vascular responses in glabrous and nonglabrous skin with increasing core temperature during exercise.

    PubMed

    Yamazaki, Fumio; Sone, Ryoko

    2006-07-01

    To elucidate the characteristics of vasomotor control in glabrous and nonglabrous skin during dynamic exercise, we compared the vascular responses in both areas to increasing core temperature during the cycle exercise for 30 min at different intensities in the range 20-60% of peak oxygen consumption (VO(2peak)) in a total of 13 male and four female subjects in two experimental protocols. Skin blood flow was monitored using laser Doppler flowmetry. In protocol 1, the slope of the relationship between esophageal temperature (T (es)) and cutaneous vascular conductance (CVC) in the early phase of the exercise decreased (P < 0.05) with increasing exercise intensity at glabrous sites (palm) but not nonglabrous sites (dorsal hand). In protocol 2, to examine whether a difference in vascular responses in the two areas is due to the adrenergic vasoconstrictor system, the release of norepinephrine from adrenergic nerves in forearm and palmar skin was blocked locally by iontophoresis of bretylium tosylate (BT). The administration of BT diminished completely the change of CVC in the palm during the exercise but did not alter the response in the forearm compared with the untreated site. In the two areas, neither the T (es) threshold for vasodilation nor the change in CVC above the threshold in the middle and late phase of the exercise was influenced by the intensity of the exercise. These results suggest that, in the early phase of the exercise, light-to-moderate exercise reduces in an intensity-dependent manner the thermal sensitivity for vasodilation in glabrous skin but not nonglabrous skin via an adrenergic vasoconstrictor pathway.

  12. Bactericidal Effects against S. aureus and Physicochemical Properties of Plasma Activated Water stored at different temperatures.

    PubMed

    Shen, Jin; Tian, Ying; Li, Yinglong; Ma, Ruonan; Zhang, Qian; Zhang, Jue; Fang, Jing

    2016-06-27

    Water activated by non-thermal plasma creates an acidified solution containing reactive oxygen and nitrogen species, known as plasma-activated water (PAW). The objective of this study was to investigate the effects of different storage temperatures (25 °C, 4 °C, -20 °C, -80 °C) on bactericidal activities against S. aureus and physicochemical properties of PAW up to 30 days. Interestingly, PAW stored at -80 °C yielded the best antibacterial activity against Staphylococcus aureus, 3~4 log reduction over a 30-day period after PAW generation; meanwhile, PAW stored at 25 °C, 4 °C, and -20 °C, respectively, yielded 0.2~2 log decrease in cell viability after the same exposure and storage time. These results were verified by scanning electron microscope (SEM). The physicochemical properties of PAW stored at different temperatures were evaluated, including pH, oxidation reduction potential (ORP), and hydrogen peroxide, nitrate, nitrite anion and NO radical levels. These findings suggested that bacterial activity of PAW stored at 25 °C, 4 °C, -20 °C decreased over time, and depended on three germicidal factors, specifically ORP, H2O2, and NO3(-). Moreover, PAW stored at -80 °C retained bactericidal activity, with NO2(-) contributing to bactericidal ability in association with H2O2. Our findings provide a basis for PAW storage and practical applications in disinfection and food preservation.

  13. Shelf-life of vacuum-packed cooked ring sausages at different chill temperatures.

    PubMed

    Korkeala, H; Alanko, T; Mäkelä, P; Lindroth, S

    1989-11-01

    Microbiological and sensory changes in 313 vacuum-packed cooked ring sausages from 28 different production runs and stored at 2, 4, 8 or 12 degrees C were monitored as a function of time. The sensory scores started to decrease at a level of approx. 10(7) lactobacilli/g. The judges began considering the samples unfit for human consumption when the lactobacilli counts were between 10(7) and 10(8) cfu/g; above a level of 10(8) cfu/g most of the samples were deemed unfit. At 2 degrees C, however, spoilage did not always seem to be microbiological, and four out of six different production runs were deemed unfit without any marked increase in microbial counts. In such cases, the judges described the sensory defects as a 'musty' rather than a sour aroma and taste. The sausages were deemed unfit when the lactobacilli were in a stationary growth phase which was considerably later than the point when the bacterial counts exceeded 10(7) cfu/g. The mean length of this delay was 30, 19, 16 and 7 days at 2, 4, 8 and 12 degrees C, respectively. The average shelf-lives were 55, 43, 29 and 17 days at 2, 4, 8 and 12 degrees C, respectively. The dependence of shelf-life on temperature can be formulated as follows: Shelf-life = 10(1.835 - 0.048 X temperature) The maximal shelf-life of this product, including nonmicrobiological spoilage, is assessed as approx. 10-11 weeks. A lactobacilli count greater than 10(7) cfu/g indicates that either the spoilage process has started or the product is already spoiled. When the lactobacilli count exceeds 10(8) cfu/g it is highly probable that the sausage sample is unacceptable.

  14. [Effects of day and night temperature difference on growth, development, yield and fruit quality of tomatoes].

    PubMed

    Li, Li; Li, Jia; Gao, Qing; Chen, Jin-xing

    2015-09-01

    Abstract: The effects of day and night temperature difference (DIF) on tomato's growth were studied in three precisely controlled units in phytotron. Set DIF as 6 °C (25/19 C), 8 °C (26/18 °C), 10 °C (27/17 °C) respectively, with the same diurnal mean temperature as 22 °C. The results showed that, different tomato varieties needed different suitable DIF at different growth stages. Before flouring, compared with DIF 6 °C , DIF 8 °C could significantly improve the growth and development of the wild currant tomato LA1781, increasing the plant height by 23.1%, fastening leaf development by 1-2 leaves, advancing flowers by 7 d. DIF 10 °C had similar effects with DIF 8 °C on LA1781. As to the cultured ordinary tomatoes LA2397 and LA0490, DIF 6 °C made the seedlings grow well, DIF 8 °C had no significant improved effects on seedlings, DIF 10 °C depressed the seedling's growth and flouring, decreasing the plant height by 12.0%-18.3%, lowering the leaf development by 2-3 leaves, delaying flouring by 2-4 d. But DIF 10 °C increased the dry aboveground mass of these three varieties by 25.2%-44.2%. After flouring, compared with DIF 6 °C, DIF 10 °C could significantly improve the yield and fruit quality of LA1781, increasing fruit number by 34.7%, yield per plant by 92.1%, single fruit mass by 40.0%, soluble sugar content by 16.3%, lycopene content by 95.6%. Compared with DIF 6 °C, LA2397 and LA0490 had higher yields and better fruit quality under DIF 8 °C, and lycopene content increased more than twice as that under DIF 6 °C. Under DIF 10 °C, yields of LA2397 and LA0490 slightly decreased (5.0%), soluble sugar contents of fruit decreased, but fruit size and lycopene content increased. The results showed that, DIF should not be very great in the seedling period of tomatoes, and a moderate DIF in flower and fruit periods could improve the yield and fruit quality, but a too high DIF would result in poor growth and yield reduction.

  15. Noninvasive assessment of muscle temperature during rest, exercise, and postexercise recovery in different environments.

    PubMed

    Flouris, Andreas D; Webb, Paul; Kenny, Glen P

    2015-05-15

    We introduced noninvasive and accurate techniques to estimate muscle temperature (Tm) of vastus lateralis (VL), triceps brachii (TB), and trapezius (TRAP) during rest, exercise, and postexercise recovery using the insulation disk (iDISK) technique. Thirty-six volunteers (24 men, 12 women; 73.0 ± 12.2 kg; 1.75 ± 0.07 m; 24.4 ± 5.5 yr; 49.2 ± 6.8 ml·kg(-1)·min(-1) peak oxygen uptake) underwent periods of rest, cycling exercise at 40% of peak oxygen uptake, and postexercise recovery in three environments: Normal (24°C, 56% relative humidity), Hot-Humid (30°C, 60% relative humidity), and Hot-Dry (40°C, 24% relative humidity). Participants were randomly allocated into the "model" and the "validation" groups. Results in the model group demonstrated that Tm (VL: 36.65 ± 1.27°C; TB: 35.76 ± 1.73°C; TRAP: 36.53 ± 0.96°C) was increased compared with iDISK (VL: 35.67 ± 1.71°C; TB: 34.77 ± 2.27°C; TRAP: 35.98 ± 1.34°C) across all environments (P < 0.001). Stepwise regression analysis generated models that accurately predicted Tm (predTm) of VL (R(2) = 0.73-0.91), TB (R(2) = 0.85-0.93), and TRAP (R(2) = 0.84-0.86) using iDISK and the difference between the current iDISK temperature and that recorded between 1 and 4 min before. Cross-validation analyses in the validation group demonstrated small differences (P < 0.05) of no physiological significance, small effect size of the differences, and strong associations (r = 0.85-0.97; P < 0.001) between Tm and predTm. Moreover, narrow 95% limits of agreement and low percent coefficient of variation were observed between Tm and predTm. It is concluded that the developed noninvasive, practical, and inexpensive techniques provide accurate estimations of VL, TB, and TRAP Tm during rest, cycling exercise, and postexercise recovery.

  16. Seasonal differences in intraseasonal and interannual variability of Mediterranean Sea surface temperature

    NASA Astrophysics Data System (ADS)

    Zveryaev, Igor I.

    2015-04-01

    Sea surface temperature (SST) data from the NOAA OI SST data set for 1982-2011 are used to investigate intraseasonal and interannual variability of Mediterranean SST during winter and summer seasons. It is shown that during winter the intraseasonal SST fluctuations are larger than the interannual SST variations in the western Mediterranean (e.g., the Tyrrhenian Sea), but smaller in the central and eastern Mediterranean Sea. In summer, the intraseasonal SST fluctuations are larger in almost the entire Mediterranean basin. Also summertime intraseasonal SST fluctuations are larger (up to three times near the Gulf of Lions) than their wintertime counterparts in the entire Mediterranean basin. The interannual SST variations are larger during summer in the western and central Mediterranean Sea and during winter in its eastern part. The leading empirical orthogonal functions (EOFs) of the Mediterranean SST and of the intensities of its intraseasonal fluctuations are characterized by the differing spatial-temporal structures both during winter and summer implying that their interannual variability is driven by different physical mechanisms. During winter, the EOF-1 of SST is associated with the East Atlantic teleconnection, whereas EOF-1 of the intensity of intraseasonal fluctuations is not linked significantly to regional atmospheric dynamics. The second EOFs of these variables are associated, respectively, with the East Atlantic/West Russia and the North Atlantic teleconnections. While during summer the atmospheric influence on Mediterranean SST is generally weaker, it is revealed that the EOF-1 of the intensity of intraseasonal SST fluctuations is linked to the Polar teleconnection.

  17. Assessment of acute toxicity of carbofuran in Macrobrachium olfersii (Wiegmann, 1836) at different temperature levels.

    PubMed

    Barbieri, Edison; Moreira, Priscila; Luchini, Luiz Alberto; Hidalgo, Karla Ruiz; Muñoz, Alejandro

    2016-01-01

    Carbofuran (2,3-dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate; C12H15NO3) is one of the most toxic carbamate pesticides. For acute toxicity of carbofuran, juveniles of Macrobrachium olfersii were exposed to different concentrations of carbofuran using the static renewal method at different temperature levels (15, 20 and 25°C) at pH 7.0. The main purpose of the present study was to detect the acute toxicity of carbofuran to M. olfersii and investigate its effects on oxygen consumption and ammonium excretion; these tests have not been carried out in this species before. First, the acute toxicity - median lethal concentration - of carbofuran to M. olfersii for 24, 48, 72 and 96 h was examined, which resulted in the following values: 1.64, 1.22, 0.86 and 0.42 mg L(-1), respectively. Furthermore, we also found that carbofuran caused an inhibition in oxygen consumption of 60.6, 65.3 and 66.2% with respect to the control. In addition, after separate exposures to carbofuran, elevations in ammonium excretion were more than 500% with respect to the control.

  18. Solution behaviour and sweetness response of D-Mannitol at different temperatures.

    PubMed

    Jamal, Muhammad Asghar; Rashad, Muhammad; Khosa, Muhammad Kaleem; Bhatti, Ijaz A; Zia, Khalid Mahmood

    2014-06-15

    The solution properties of d-Mannitol (DM) were studied to explore sweetness response and molecular interactions in aqueous solutions at different temperatures. The density (ρ) and ultrasonic velocity (μ) were measured at 20-45°C using density sound velocity metre (DSA 5000M). The results obtained were used to compute apparent and partial molar volume, apparent specific volumes, partial molar expansibility, apparent molar isentropic compressibility and compressibility hydration number. The partial molar volume (ΦV°) indicates hydrophilic interactions dominating in aqueous solution of DM. The quality of taste has been determined from apparent specific volumes (ASV) data at 20-45°C and 0.04-0.89 mol kg(-1).The apparent molar isentropic compressibility (ΦK(s)) and hydration number (nH) conferred pre-dominance of solute-solvent interactions, whereas partial molar expansibility (ΦE°) and related standards predicted structure making behaviour of DM. This study may provide new insights in elucidation of mechanistic differences between sweeteners and their mode of interactions.

  19. 2D-PAGE protein analysis of dinoflagellate Alexandrium minutum based on three different temperatures

    NASA Astrophysics Data System (ADS)

    Latib, Norhidayu Abdul; Norshaha, Safida Anira; Usup, Gires; Yusof, Nurul Yuziana Mohd

    2015-09-01

    Harmful algae bloom or red tide seems to be considered as threat to ecosystem, especially to human consumption because of the production of neurotoxin by dinoflagellates species such as Alexandrium minutum which can lead to paralytic shellfish poisoning. The aim of this study is to determine the most suitable method for protein extraction of A. minutum followed by determination of differential protein expression of A. minutum on three different temperatures (15°C, 26°C and 31.5°C). After the optimization, the protein extract was subjected to two-dimensional polyacrylamide gel electrophoresis (2-DE) to compare the intensity and distribution of the protein spots. Based on quantitative and qualitative protein assessment, use of Trizol reagent is the most suitable method to extract protein from A. minutum. 2-DE analysis of the samples results in different distribution and intensity of the protein spots were compared between 15°C, 26°C and 31.5°C.

  20. Understanding Differences in Upper Stratospheric Ozone Response to Changes in Chlorine and Temperature as Computed Using CCMVal Models

    NASA Technical Reports Server (NTRS)

    Douglass, A. R.; Stolarski, R. S.; Strahan, S. E.; Oman, L. D.

    2012-01-01

    Projections of future ozone levels are made using models that couple a general circulation model with a representation of atmospheric photochemical processes, allowing interactions among photochemical processes, radiation, and dynamics. Such models are known as chemistry and climate models (CCMs). Although developed from common principles and subject to the same boundary conditions, simulated ozone time series vary for projections of changes in ozone depleting substances (ODSs) and greenhouse gases. In the upper stratosphere photochemical processes control ozone level, and ozone increases as ODSs decrease and temperature decreases due to greenhouse gas increase. Simulations agree broadly but there are quantitative differences in the sensitivity of ozone to chlorine and to temperature. We obtain insight into these differences in sensitivity by examining the relationship between the upper stratosphere annual cycle of ozone and temperature as produced by a suite of models. All simulations conform to expectation in that ozone is less sensitive to temperature when chlorine levels are highest because chlorine catalyzed loss is nearly independent of temperature. Differences in sensitivity are traced to differences in simulated temperature, ozone and reactive nitrogen when chlorine levels are close to background. This work shows that differences in the importance of specific processes underlie differences in simulated sensitivity of ozone to composition change. This suggests a) the multi-model mean is not a best estimate of the sensitivity of upper ozone to changes in ODSs and temperature; b) the spread of values is not an appropriate measure of uncertainty.

  1. Effects of rapid temperature changes on HK, PK and HSP70 of Litopenaeus vannamei in different seasons

    NASA Astrophysics Data System (ADS)

    Guo, Biao; Wang, Fang; Dong, Shuanglin; Hou, Chunqiang

    2010-09-01

    Activities of hexokinase (HK), pyruvate kinase (PK) and levels of HSP70 were measured to evaluate the response of Litopenaeus vannamei to rapid temperature changes under controlled laboratory conditions. Shrimps were subjected to a quick temperature change from 27°C to 17°C for the summer case (Cold temperature treatment), or from 17°C to 27°C for the winter case (Warm temperature treatment). After 0.5, 1, 3, 6, 12, 24, 48, and 72 h of exposure time, shrimps were sampled and prepared for further analysis. The results showed that the effect of acute temperature changes on activities of HK was significant. Patterns of variations of the two glycolytic enzymes suggested that enzymes in the glycolysis cycle could adjust their activities to meet the acute temperature change. The HSP70 level increased in both cold and warm temperature treatments, suggesting that the rapid temperature changes activated the process of body’s self-protection. But the difference in expression peak of HSP70 might be related to the different body size and the higher thermal sensitivity to temperature increase than to temperature decrease of L. vannamei.

  2. Effect of different arbuscular mycorrhizal fungi on growth and physiology of maize at ambient and low temperature regimes.

    PubMed

    Chen, Xiaoying; Song, Fengbin; Liu, Fulai; Tian, Chunjie; Liu, Shengqun; Xu, Hongwen; Zhu, Xiancan

    2014-01-01

    The effect of four different arbuscular mycorrhizal fungi (AMF) on the growth and lipid peroxidation, soluble sugar, proline contents, and antioxidant enzymes activities of Zea mays L. was studied in pot culture subjected to two temperature regimes. Maize plants were grown in pots filled with a mixture of sandy and black soil for 5 weeks, and then half of the plants were exposed to low temperature for 1 week while the rest of the plants were grown under ambient temperature and severed as control. Different AMF resulted in different root colonization and low temperature significantly decreased AM colonization. Low temperature remarkably decreased plant height and total dry weight but increased root dry weight and root-shoot ratio. The AM plants had higher proline content compared with the non-AM plants. The maize plants inoculated with Glomus etunicatum and G. intraradices had higher malondialdehyde and soluble sugar contents under low temperature condition. The activities of catalase (CAT) and peroxidase of AM inoculated maize were higher than those of non-AM ones. Low temperature noticeably decreased the activities of CAT. The results suggest that low temperature adversely affects maize physiology and AM symbiosis can improve maize seedlings tolerance to low temperature stress.

  3. Migration of DEHP and DINP into dust from PVC flooring products at different surface temperature.

    PubMed

    Jeon, Seunghwan; Kim, Ki-Tae; Choi, Kyungho

    2016-03-15

    Phthalates are important endocrine disrupting chemicals that have been linked to various adverse human health effects. Phthalates are ubiquitously present in indoor environment and could enter humans. Vinyl or PVC floorings have been recognized as one of important sources of phthalate release to indoor environment including house dust. In the present study, we estimated the migration of di(2-ethylhexyl)phthalate (DEHP) and di-isononyl phthalate (DINP) from the flooring materials into the dust under different heating conditions. For this purpose, a small chamber specifically designed for the present study and a Field and Laboratory Emission Cell (FLEC) were used, and four major types of PVC flooring samples including two UV curing paint coated, an uncoated residential, and a wax-coated commercial type were tested. Migration of DEHP was observed for an uncoated residential type and a wax-coated commercial type flooring. After 14 days of incubation, the levels of DEHP in the dust sample was determined at room temperature on average (standard deviation) at 384 ± 19 and 481 ± 53 μg/g, respectively. In contrast, migration of DINP was not observed. The migration of DEHP was strongly influenced by surface characteristics such as UV curing coating. In the residential flooring coated with UV curing paint, migration of DEHP was not observed at room temperature. But under the heated condition, the release of DEHP was observed in the dust in the FLEC. Migration of DEHP from flooring materials increased when the flooring was heated (50 °C). In Korea, heated flooring system, or 'ondol', is very common mode of heating in residential setting, therefore the contribution of PVC flooring to the total indoor DEHP exposure among general population is expected to be greater especially during winter season when the floor is heated.

  4. Circadian fluctuation in heat production of young calves at different ambient temperatures in relation to posture.

    PubMed

    Schrama, J W; Noordhuizen, J P; Arieli, A; Brandsma, H A; van der Linden, J M; Verstegen, M W

    1994-03-01

    Circadian fluctuations in the effect of ambient temperature (Ta) on heat production (Htot) and its relation to posture were investigated in young calves in this study. Twenty-three 6-d-old Holstein-Friesian male calves were assigned to one of four Ta treatments: 5, 9, 13, or 18 degrees C. Heat production was measured per calf continuously every 9 min by indirect calorimetry for 5 d. The posture during these 9-min periods was derived from physical activity measurements by Doppler-radar meters. Heat production varied within a day; it was highest when calves were drinking (milk or water). The influence of Ta on Htot was larger for the light (including feeding periods) than for the dark phase of the day, being related to the larger Ta effect during the feeding periods. Lower critical temperatures (LCT) were 14.1, 15.2, and 16.8 degrees C and extra thermal heat productions below LCT (ETH) were 8.48, 8.28, and 11.55 kJ.kg-.75.d-1.C degrees-1 for the dark, the light (excluding feeding periods), and the feeding phase during the day, respectively. Time spent standing was not affected by Ta but varied during the day (24-h period). Averaged over Ta, 51% of the within day variation in Htot was accounted for by the calf's posture. Correction of Htot for the time spent standing reduced the difference in both ETH and LCT between phases of the day. The present study demonstrates that circadian fluctuations exist in the thermal requirements of young calves. Part of these fluctuations are related to within-day variation in time spent standing.

  5. Small change, big difference: Sea surface temperature distributions for tropical coral reef ecosystems, 1950-2011

    NASA Astrophysics Data System (ADS)

    Lough, J. M.

    2012-09-01

    Changes in tropical sea surface temperature (SST) are examined over the period 1950-2011 during which global average temperature warmed by 0.4°C. Average tropical SST is warming about 70% of the global average rate. Spatially, significant warming between the two time periods, 1950-1980 and 1981-2011, has occurred across 65% of the tropical oceans. Coral reef ecosystems occupy 10% of the tropical oceans, typically in regions of warmer (+1.8°C) and less variable SST (80% of months within 3.3°C range) compared to non-reef areas (80% of months within 7.0°C range). SST is a primary controlling factor of coral reef distribution and coral reef organisms have already shown their sensitivity to the relatively small amount of warming observed so far through, for example, more frequent coral bleaching events and outbreaks of coral disease. Experimental evidence is also emerging of possible thermal thresholds in the range 30°C-32°C for some physiological processes of coral reef organisms. Relatively small changes in SST have already resulted in quite large differences in SST distribution with a maximum ‘hot spot’ of change in the near-equatorial Indo-Pacific which encompasses both the Indo-Pacific warm pools and the center of coral reef biodiversity. Identification of this hot spot of SST change is not new but this study highlights its significance with respect to tropical coral reef ecosystems. Given the modest amount of warming to date, changes in SST distribution are of particular concern for coral reefs given additional local anthropogenic stresses on many reefs and ongoing ocean acidification likely to increasingly compromise coral reef processes.

  6. Low temperature CO oxidation on differently prepared TiO2(110) supported Au catalysts

    NASA Astrophysics Data System (ADS)

    Berkó, András; Majzik, Zsolt; Mária Kiss, Anna

    2007-03-01

    The preparation of Au/TiO2(110) planar catalysts and the low temperature (LT) oxidation of CO (in H2) were investigated by Scanning Tunnelling Microscopy (STM), Auger-electron Spectroscopy (AES) and Thermal Programmed Reaction (TPR). The distribution and the mean size of the Au particles were modified by different pretreatments of the support: (A) Ar+ bombardment; deposition to (B) 0.05 ML of K or (C) 0.5 ML of Mo. It was shown that the mean size of the Au particles formed at RT is 3-4 nm on the clean TiO2(110) surface and this value deacreased to 1.5-2 nm for all pretreated supports. These 2D catalysts were tested in the LT oxidation (PROX) of CO. The same reaction conditions were kept for all experiments: the reaction chamber was filled up to 0.5 hPa O2, 0.5 hPa CO and 9 hPa H2 and the temperature of the catalyst was increased from 310 K to 400 K, 450 K or 500K for 60 minutes. The clean, Ar+pretreated, K or Mo preexposed oxide surfaces exhibited no activity in the PROX reaction. By the deposition of Au of 1-3 monolayer on to these surfaces, however, an enhancement of CO2 in the gas phase was clearly detected. The clean TiO2(110) surface prooved to be the best support for gold, any modification of the support resulted in a loss of the activity. For all cases dependently on the pretreatments, the mean size of the Au particles increased significantly up to 4-8 nm in the PROX at 500 K.

  7. Developing a heatwave early warning system for Sweden: evaluating sensitivity of different epidemiological modelling approaches to forecast temperatures.

    PubMed

    Åström, Christofer; Ebi, Kristie L; Langner, Joakim; Forsberg, Bertil

    2014-12-23

    Over the last two decades a number of heatwaves have brought the need for heatwave early warning systems (HEWS) to the attention of many European governments. The HEWS in Europe are operating under the assumption that there is a high correlation between observed and forecasted temperatures. We investigated the sensitivity of different temperature mortality relationships when using forecast temperatures. We modelled mortality in Stockholm using observed temperatures and made predictions using forecast temperatures from the European Centre for Medium-range Weather Forecasts to assess the sensitivity. We found that the forecast will alter the expected future risk differently for different temperature mortality relationships. The more complex models seemed more sensitive to inaccurate forecasts. Despite the difference between models, there was a high agreement between models when identifying risk-days. We find that considerations of the accuracy in temperature forecasts should be part of the design of a HEWS. Currently operating HEWS do evaluate their predictive performance; this information should also be part of the evaluation of the epidemiological models that are the foundation in the HEWS. The most accurate description of the relationship between high temperature and mortality might not be the most suitable or practical when incorporated into a HEWS.

  8. Developing a Heatwave Early Warning System for Sweden: Evaluating Sensitivity of Different Epidemiological Modelling Approaches to Forecast Temperatures

    PubMed Central

    Åström, Christofer; Ebi, Kristie L.; Langner, Joakim; Forsberg, Bertil

    2014-01-01

    Over the last two decades a number of heatwaves have brought the need for heatwave early warning systems (HEWS) to the attention of many European governments. The HEWS in Europe are operating under the assumption that there is a high correlation between observed and forecasted temperatures. We investigated the sensitivity of different temperature mortality relationships when using forecast temperatures. We modelled mortality in Stockholm using observed temperatures and made predictions using forecast temperatures from the European Centre for Medium-range Weather Forecasts to assess the sensitivity. We found that the forecast will alter the expected future risk differently for different temperature mortality relationships. The more complex models seemed more sensitive to inaccurate forecasts. Despite the difference between models, there was a high agreement between models when identifying risk-days. We find that considerations of the accuracy in temperature forecasts should be part of the design of a HEWS. Currently operating HEWS do evaluate their predictive performance; this information should also be part of the evaluation of the epidemiological models that are the foundation in the HEWS. The most accurate description of the relationship between high temperature and mortality might not be the most suitable or practical when incorporated into a HEWS. PMID:25546283

  9. The EUSTACE project: combining different components of the observing system to deliver global, daily information on surface air temperature

    NASA Astrophysics Data System (ADS)

    Rayner, Nick

    2016-04-01

    Day-to-day variations in surface air temperature affect society in many ways and are fundamental information for many climate services; however, daily surface air temperature measurements are not available everywhere. A global daily analysis cannot be achieved with measurements made in situ alone, so incorporation of satellite retrievals is needed. To achieve this, we must develop an understanding of the relationships between traditional surface air temperature measurements and retrievals of surface skin temperature from satellite measurements, i.e. Land Surface Temperature, Ice Surface Temperature, Sea Surface Temperature and Lake Surface Water Temperature. Here we reflect on our experience so far within the Horizon 2020 project EUSTACE of using satellite skin temperature retrievals to help us to produce a fully-global daily analysis (or ensemble of analyses) of surface air temperature on the centennial scale, integrating different ground-based and satellite-borne data types and developing new statistical models of how surface air temperature varies in a connected way from place to place. We will present plans and progress along this road in the EUSTACE project (2015-June 2018): - providing new, consistent, multi-component estimation of uncertainty in surface skin temperature retrievals from satellites; - identifying inhomogeneities in daily surface air temperature measurement series from weather stations and correcting for these over Europe; - estimating surface air temperature over all surfaces of Earth from surface skin temperature retrievals; - using new statistical techniques to provide information on higher spatial and temporal scales than currently available, making optimum use of information in data-rich eras. Information will also be given on how interested users can become involved.

  10. Isotopic ordering in eggshells reflects body temperatures and suggests differing thermophysiology in two Cretaceous dinosaurs

    NASA Astrophysics Data System (ADS)

    Eagle, Robert A.; Enriquez, Marcus; Grellet-Tinner, Gerald; Pérez-Huerta, Alberto; Hu, David; Tütken, Thomas; Montanari, Shaena; Loyd, Sean J.; Ramirez, Pedro; Tripati, Aradhna K.; Kohn, Matthew J.; Cerling, Thure E.; Chiappe, Luis M.; Eiler, John M.

    2015-10-01

    Our understanding of the evolutionary transitions leading to the modern endothermic state of birds and mammals is incomplete, partly because tools available to study the thermophysiology of extinct vertebrates are limited. Here we show that clumped isotope analysis of eggshells can be used to determine body temperatures of females during periods of ovulation. Late Cretaceous titanosaurid eggshells yield temperatures similar to large modern endotherms. In contrast, oviraptorid eggshells yield temperatures lower than most modern endotherms but ~6 °C higher than co-occurring abiogenic carbonates, implying that this taxon did not have thermoregulation comparable to modern birds, but was able to elevate its body temperature above environmental temperatures. Therefore, we observe no strong evidence for end-member ectothermy or endothermy in the species examined. Body temperatures for these two species indicate that variable thermoregulation likely existed among the non-avian dinosaurs and that not all dinosaurs had body temperatures in the range of that seen in modern birds.

  11. Moisture and temperature controls on nitrification differ among ammonia oxidizer communities from three alpine soil habitats

    NASA Astrophysics Data System (ADS)

    Osborne, Brooke B.; Baron, Jill S.; Wallenstein, Matthew D.

    2016-03-01

    Climate change is altering the timing and magnitude of biogeochemical fluxes in many highelevation ecosystems. The consequent changes in alpine nitrification rates have the potential to influence ecosystem scale responses. In order to better understand how changing temperature and moisture conditions may influence ammonia oxidizers and nitrification activity, we conducted laboratory incubations on soils collected in a Colorado watershed from three alpine habitats (glacial outwash, talus, and meadow). We found that bacteria, not archaea, dominated all ammonia oxidizer communities. Nitrification increased with moisture in all soils and under all temperature treatments. However, temperature was not correlated with nitrification rates in all soils. Site-specific temperature trends suggest the development of generalist ammonia oxidzer communities in soils with greater in situ temperature fluctuations and specialists in soils with more steady temperature regimes. Rapidly increasing temperatures and changing soil moisture conditions could explain recent observations of increased nitrate production in some alpine soils.

  12. Moisture and temperature controls on nitrification differ among ammonia oxidizer communities from three alpine soil habitats

    USGS Publications Warehouse

    Osborne, Brooke B; Baron, Jill S.; Wallenstein, Matthew D.

    2016-01-01

    Climate change is altering the timing and magnitude of biogeochemical fluxes in many high elevation ecosystems. The consequent changes in alpine nitrification rates have the potential to influence ecosystem scale responses. In order to better understand how changing temperature and moisture conditions may influence ammonia oxidizers and nitrification activity, we conducted laboratory incubations on soils collected in a Colorado watershed from three alpine habitats (glacial outwash, talus, and meadow). We found that bacteria, not archaea, dominated all ammonia oxidizer communities. Nitrification increased with moisture in all soils and under all temperature treatments. However, temperature was not correlated with nitrification rates in all soils. Site-specific temperature trends suggest the development of generalist ammonia oxidizer communities in soils with greater in situ temperature fluctuations and specialists in soils with more steady temperature regimes. Rapidly increasing temperatures and changing soil moisture conditions could explain recent observations of increased nitrate production in some alpine soils.

  13. [Comparison of force and shortening velocity in fast and slow rabbit muscle fibers at different temperatures].

    PubMed

    Kochubeĭ, P V; Bershitskiĭ, S Iu

    2014-01-01

    The temperature dependence of force, maximal shortening velocity and power of maximally activated single permeabilized fibers from fast and slow muscles of the rabbit were recorded in a temperature range from 10 to 35 degrees C with 5 degrees C step. It was found that temperature dependence of force of both types of fibers is identical. Averaged maximal shortening velocity in the slow fibers, unlike the fast fibers, had no statistically significant temperature dependence that is not in agreement with the data obtained on intact rat muscle fibers and in an in vitro motility assay. However maximal shortening velocity in each individual slow fiber did depend on temperature. The temperature dependence of power of the slow fibers was lower than that of the fast ones. Because of large data scattering the average temperature dependence of power of the slow fibers was significantly lower than that in individual slow fibers.

  14. Evolution of morphology and structure of Pb thin films grown by pulsed laser deposition at different substrate temperatures

    SciTech Connect

    Lorusso, Antonella Maiolo, Berlinda; Perrone, Alessio; Gontad, Francisco; Maruccio, Giuseppe; Tasco, Vittorianna

    2014-03-15

    Pb thin films were prepared by pulsed laser deposition on a Si (100) substrate at different growth temperatures to investigate their morphology and structure. The morphological analysis of the thin metal films showed the formation of spherical submicrometer grains whose average size decreased with temperature. X-ray diffraction measurements confirmed that growth temperature influences the Pb polycrystalline film structure. A preferred orientation of Pb (111) normal to the substrate was achieved at 30 °C and became increasingly pronounced along the Pb (200) plane as the substrate temperature increased. These thin films could be used to synthesize innovative materials, such as metallic photocathodes, with improved photoemission performances.

  15. Reproduction and survival under different water temperatures of Gyrodactylus mexicanus (Platyhelminthes: Monogenea), a parasite of Girardinichthys multiradiatus in Central Mexico.

    PubMed

    Sereno-Uribe, Ana L; Zambrano, Luis; García-Varela, Martín

    2012-12-01

    Gyrodactylid population growth may depend on abiotic variables such as temperature. We tested the survival and reproductive rate of Gyrodactylus mexicanus, a parasite infecting fins of Girardinichthys multiradiatus, at 3 different water temperatures, 10-13, 19-22, and 24 C. The temporal sequence of birth and age at death of each parasite isolated from the hosts was recorded through at least 8 generations. Our results showed that the average number of offspring per parasite was 2.0 when averaged across all temperatures. However, the generation time was negatively correlated with temperature. The innate capacity for increase (r(m)) was positively correlated with water temperature: from 0.29 parasite/day at 13 C to 0.48 parasite/day at 24 C. These data confirm that water temperature has a direct influence on parasite population dynamics. The current study represents the first contribution to understanding the population ecology of the monogenean G. mexicanus in central Mexico.

  16. The research of the temperature difference effect on the sensitivity of the LNA parameters

    NASA Astrophysics Data System (ADS)

    Zybin, A. A.; Vyuginov, V. N.; Tikhomirov, V. G.; Shaganov, P. A.; Vidyakin, S. I.; Kukhareva, E. S.

    2016-08-01

    There is an investigation of the functional characteristics changes of a low noise amplifier under the influence of temperature changes with helping of a mathematical modelling in particular CAD AWRDE Microwave Office. The relative changes of the functional characteristics of electrical parameters of a low noise amplifier at the fixed frequency as a result of influence of the environment temperature are researching. As a result, temperature changes have a greater impact on the reflection coefficient than on the noise figure and gain.

  17. Chemical spray pyrolysis of β-In2S3 thin films deposited at different temperatures

    NASA Astrophysics Data System (ADS)

    Sall, Thierno; Marí Soucase, Bernabé; Mollar, Miguel; Hartitti, Bouchaib; Fahoume, Mounir

    2015-01-01

    In2S3 thin films were deposited onto indium tin oxide-coated glass substrates by chemical spray pyrolysis while keeping the substrates at different temperatures. The structures of the sprayed In2S3 thin films were characterized by X-ray diffraction (XFD). The quality of the thin films was determined by Raman spectroscopy. Scanning electron microscopy (SEM) and atomic force microscopy were used to explore the surface morphology and topography of the thin films, respectively. The optical band gap was determined based on optical transmission measurements. The indium sulfide phase exhibited a preferential orientation in the (0, 0, 12) crystallographic direction according to the XRD analysis. The phonon vibration modes determined by Raman spectroscopy also confirmed the presence of the In2S3 phase in our samples. According to SEM, the surface morphologies of the films were free of defects. The optical band gap energy varied from 2.82 eV to 2.95 eV.

  18. Dynamics of thermographic skin temperature response during squat exercise at two different speeds.

    PubMed

    Formenti, Damiano; Ludwig, Nicola; Trecroci, Athos; Gargano, Marco; Michielon, Giovanni; Caumo, Andrea; Alberti, Giampietro

    2016-07-01

    Low intensity resistance training with slow movement and tonic force generation has been shown to create blood flow restriction within muscles that may affect thermoregulation through the skin. We aimed to investigate the influence of two speeds of exercise execution on skin temperature dynamics using infrared thermography. Thirteen active males performed randomly two sessions of squat exercise (normal speed, 1s eccentric/1s concentric phase, 1s; slow speed, 5s eccentric/5s concentric phase, 5s), using ~50% of 1 maximal repetition. Thermal images of ST above muscles quadriceps were recorded at a rate of 0.05Hz before the exercise (to determine basal ST) and for 480s following the initiation of the exercise (to determine the nonsteady-state time course of ST). Results showed that ST changed more slowly during the 5s exercise (p=0.002), whereas the delta (with respect to basal) excursions were similar for the two exercises (p>0.05). In summary, our data provided a detailed nonsteady-state portrait of ST changes following squat exercises executed at two different speeds. These results lay the basis for further investigations entailing the joint use of infrared thermography and Doppler flowmetry to study the events taking place both at the skin and the muscle level during exercises executed at slow speed.

  19. CO{sub 2}-gasification reactivity of different carbonaceous materials at elevated temperatures

    SciTech Connect

    Gu, J.; Wu, S.; Wu, Y.; Gao, J.

    2009-07-01

    At the atmospheric pressure and at the temperatures between 1,223 and 1,673 K, the CO{sub 2} gasification reactivity of seven different carbonaceous materials comprising coal tar pitch coke, petroleum coke, natural graphite, carbon black and three coal chars was investigated by using thermogravimetric analysis. Their crystalline structures were analyzed by X-ray diffraction (XRD). It is found that the reactivity of the chars, pitch coke and petroleum coke produced from liquid phase carbonization, is several times poorer than that of the coal chars produced from solid phase carbonization and even lower than that of natural graphite. At the same time, it is obtained that under the condition of the chemical reaction control, the apparent activation energies of the former are in the range of 135.82-174.92 kJ/mol, while those of the latter are between 89.95 kJ/mol and 110.05 kJ/mol. Besides, the reactivity of the sample has a certain correlation with the crystalline structure of the sample, i.e., the larger the fraction of the relatively better crystalline structure is, the poorer the reactivity of the sample is.

  20. Establishment of Three Francisella Infections in Zebrafish Embryos at Different Temperatures

    PubMed Central

    Brudal, Espen; Ulanova, Lilia S.; O. Lampe, Elisabeth; Rishovd, Anne-Lise; Winther-Larsen, Hanne C.

    2014-01-01

    Francisella spp. are facultative intracellular pathogens identified in increasingly diverse hosts, including mammals. F. noatunensis subsp. orientalis and F. noatunensis subsp. noatunensis infect fish inhabiting warm and cold waters, respectively, while F. tularensis subsp. novicida is highly infectious for mice and has been widely used as a model for the human pathogen F. tularensis. Here, we established zebrafish embryo infection models of fluorescently labeled F. noatunensis subsp. noatunensis, F. noatunensis subsp. orientalis, and F. tularensis subsp. novicida at 22, 28, and 32°C, respectively. All infections led to significant bacterial growth, as shown by reverse transcription-quantitative PCR (RT-qPCR), and to a robust proinflammatory immune response, dominated by increased transcription of tumor necrosis factor alpha (TNF-α) and interleukin-1β (IL-1β). F. noatunensis subsp. orientalis was the most virulent, F. noatunensis subsp. noatunensis caused chronic infection, and F. tularensis subsp. novicida showed moderate virulence and led to formation of relatively small granuloma-like structures. The use of transgenic zebrafish strains with enhanced green fluorescent protein (EGFP)-labeled immune cells revealed their detailed interactions with Francisella species. All three strains entered preferentially into macrophages, which eventually assembled into granuloma-like structures. Entry into neutrophils was also observed, though the efficiency of this event depended on the route of infection. The results demonstrate the usefulness of the zebrafish embryo model for studying infections caused by different Francisella species at a wide range of temperatures and highlight their interactions with immune cells. PMID:24614659

  1. Evaluation of infectious bursal disease virus stability at different conditions of temperature and pH.

    PubMed

    Rani, Surabhi; Kumar, Sachin

    2015-11-01

    Infectious bursal disease (IBD) is one of the highly pathogenic viral diseases of poultry. The disease poses a serious threat to the economy of many developing countries where agriculture serves as the primary source of national income. Infectious bursal disease virus (IBDV) belongs to the family Birnaviridae. The IBDV is well characterized to cause immunosuppression in poultry. The live attenuated vaccine is the only way to protect the chickens from IBDV infection. The ineffectiveness of vaccine is one of the major causes of IBDV outbreaks in field condition. In the present study, we discuss briefly about the biology of IBDV genome and its proteins under different conditions of temperature and pH in order to evaluate its infectivity under adverse physical conditions. Our results indicate that the IBDV is non-infective above 42 °C and unstable above 72 °C. However, the change in pH does not significantly contribute to the IBDV stability. The study will be useful in estimating an optimum storage condition for IBDV vaccines without causing any deterioration in its viability and effectiveness.

  2. Fatty acid modifications and cholesterol oxidation in pork loin during frying at different temperatures.

    PubMed

    Echarte, M; Ansorena, D; Astiasaran, I

    2001-07-01

    The effect of frying with sunflower oil for 4 min at different temperatures (160, 170, and 180 degrees C) on fatty acids and cholesterol of pork loin meat was studied. Total fat content increased from 5.6% in fresh loin to 7.3, 7.8, and 12.1% at 160, 170, and 180 degrees C, respectively. Interactions with culinary fat gave rise to a significant increase in unsaturated acids/saturated acids and polyunsaturated acids/saturated acids ratios, which could be considered an advantage from a nutritional point of view. Less than 1 ppm (microg/g of sample) of cholesterol oxidation products was detected in fresh loin, whereas fried loin pork contained between 8.58 and 10.89 ppm. 7-Ketocholesterol (5.99 to 8.47 ppm in fried samples) and 7beta-hydroxycholesterol (1.43 to 2.55 ppm in fried samples) were the main cholesterol oxidation products. Cholestanetriol was not detected in any sample, and small quantities of 25-hydroxycholesterol and 5,6alpha-epoxycholesterol were found in the fried sample.

  3. Soil temperature modeling at different depths using neuro-fuzzy, neural network, and genetic programming techniques

    NASA Astrophysics Data System (ADS)

    Kisi, Ozgur; Sanikhani, Hadi; Cobaner, Murat

    2016-05-01

    The applicability of artificial neural networks (ANN), adaptive neuro-fuzzy inference system (ANFIS), and genetic programming (GP) techniques in estimating soil temperatures (ST) at different depths is investigated in this study. Weather data from two stations, Mersin and Adana, Turkey, were used as inputs to the applied models in order to model monthly STs. The first part of the study focused on comparison of ANN, ANFIS, and GP models in modeling ST of two stations at the depths of 10, 50, and 100 cm. GP was found to perform better than the ANN and ANFIS-SC in estimating monthly ST. The effect of periodicity (month of the year) on models' accuracy was also investigated. Including periodicity component in models' inputs considerably increased their accuracies. The root mean square error (RMSE) of ANN models was respectively decreased by 34 and 27 % for the depths of 10 and 100 cm adding the periodicity input. In the second part of the study, the accuracies of the ANN, ANFIS, and GP models were compared in estimating ST of Mersin Station using the climatic data of Adana Station. The ANN models generally performed better than the ANFIS-SC and GP in modeling ST of Mersin Station without local climatic inputs.

  4. Investigation of potential waste material insulating properties at different temperature for thermal storage application

    NASA Astrophysics Data System (ADS)

    Ali, T. Z. S.; Rosli, A. B.; Gan, L. M.; Billy, A. S.; Farid, Z.

    2013-12-01

    Thermal energy storage system (TES) is developed to extend the operation of power generation. TES system is a key component in a solar energy power generation plant, but the main issue in designing the TES system is its thermal capacity of storage materials, e.g. insulator. This study is focusing on the potential waste material acts as an insulator for thermal energy storage applications. As the insulator is used to absorb heat, it is needed to find suitable material for energy conversion and at the same time reduce the waste generation. Thus, a small-scale experimental testing of natural cooling process of an insulated tank within a confined room is conducted. The experiment is repeated by changing the insulator from the potential waste material and also by changing the heat transfer fluid (HTF). The analysis presented the relationship between heat loss and the reserved period by the insulator. The results show the percentage of period of the insulated tank withstands compared to tank insulated by foam, e.g. newspaper reserved the period of 84.6% as much as foam insulated tank to withstand the heat transfer of cooking oil to the surrounding. The paper finally justifies the most potential waste material as an insulator for different temperature range of heat transfer fluid.

  5. Extractable and Non-Extractable Phenolics and Antioxidant Capacity of Mandarin Waste Dried at Different Temperatures.

    PubMed

    Esparza-Martínez, Francisco J; Miranda-López, Rita; Mata-Sánchez, Sara M; Guzmán-Maldonado, Salvador H

    2016-09-01

    The mandarin industry is generating more waste due to the increasing demand for juice. In this study, extractable and non-extractable phenolics as well as 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), ferric reducing ability of plasma (FRAP), and oxygen radical absorbance capacity (ORAC) antioxidant activities in Satsuma mandarin waste dried at different temperatures were determined. The amounts of non-extractable total phenols, total flavonoids, and condensed tannins measured in mandarin waste dried at 120 °C were 39.4, 44.3, and 45.6 %, respectively, which were higher than those of fresh-mandarin waste. Dried mandarin waste is rich in extractable and non-extractable hesperidin (259.86 and 182.52 mg/g, respectively) and eriocitrin (85.12 and 197.24 mg/g, respectively), as well as non-extractable gallic acid (36.08 μg/g). The antioxidant capacities of extractable and non-extractable phenolics, from the highest to the lowest, were ABTS > ORAC > DPPH > FRAP and ORAC > ABTS > DPPH > FRAP, respectively. The information reported here may encourage mandarin industry operators to re-evaluate their by-products, extending the application of mandarin fruits and reducing waste.

  6. Effect of different storage temperature on chemical composition of onion (Allium cepa L.) and its enzymes.

    PubMed

    Sharma, Kavita; Lee, Yong Rok

    2016-03-01

    Onion stored at 4, 10, and 25 °C for 9 months were analyzed for changes in quercetin and its glucosidase content, enzymes, pyruvic acid, and sugar content. During storage, concentration of quercetin and its glucosidase showed an irregular variation at all studied temperature but at 4 °C the rate was high as compared to 10 and 25 °C. The enzymatic activity of Q4'G glucosidase and Q4'glucosyltransferase increased progressively until six months at 4, 10 and 25 °C, but later it started to decrease. At 4 and 10 °C, peroxidase activity increased during the first five weeks then decreased, while at 25 °C peroxidase activity decreased progressively after two months storage. Fructose, glucose and sucrose showed a different although more regular pattern by decreasing progressively at 4, 10 °C. At 4 °C fructose and glucose accumulated in the initial 3 to 4 months of storage while sucrose was unchanged. However, at 10 and 25 °C, fructose and glucose concentration continuously decreased, while sucrose increased consistently. Onion pyruvic acid increased at 4 and 10 °C during the first six months, while at 25 °C the fluctuation was observed during the whole storage period. Overall, we conclude that storage at 4 °C maintained the quality of onions best, as evidenced by the positive changes.

  7. Harmonic analysis of GaN-HEMTs at different temperatures and frequencies using Volterra power series

    NASA Astrophysics Data System (ADS)

    Yıldırım, Remzi; Karaarslan, Ahmet

    2015-02-01

    In this study, the detailed harmonic analysis of GaN high electron mobility transistor (HEMT) at different temperatures and frequencies is presented. Volterra power series and multi-dimensional Laplace transform are used as a method. The Volterra power series is also solved up to third degree, and the small signal transfer functions of kernels (H1, H2 and H3) are obtained. The relationship between drain inductance (Ld), gate-source voltage (Vgs), impedance (ZL) and the effect of frequency (Fr) to the output gain is identified. Besides, the nonlinear gains of H1, H2 and H3 kernels of the GaN-HEMT are obtained. The inverse relationship between the output gains of H1, H2 and H3 kernels are derived. An unsuitable situation has also been identified for sub-carrier inter-modulation systems. In addition, an asymmetric structure is also obtained between the output gain of H2 and side-band frequencies. The effects of other parameters are carried out for the output gain.

  8. Detection of significant differences between absorption spectra of neutral helium and low temperature photoionized helium plasmas

    SciTech Connect

    Bartnik, A.; Wachulak, P.; Fiedorowicz, H.; Fok, T.; Jarocki, R.; Szczurek, M.

    2013-11-15

    In this work, spectral investigations of photoionized He plasmas were performed. The photoionized plasmas were created by irradiation of helium stream, with intense pulses from laser-plasma extreme ultraviolet (EUV) source. The EUV source was based on a double-stream Xe/Ne gas-puff target irradiated with 10 ns/10 J Nd:YAG laser pulses. The most intense emission from the source spanned a relatively narrow spectral region below 20 nm, however, spectrally integrated intensity at longer wavelengths was also significant. The EUV radiation was focused onto a gas stream, injected into a vacuum chamber synchronously with the EUV pulse. The long-wavelength part of the EUV radiation was used for backlighting of the photoionized plasmas to obtain absorption spectra. Both emission and absorption spectra in the EUV range were investigated. Significant differences between absorption spectra acquired for neutral helium and low temperature photoionized plasmas were demonstrated for the first time. Strong increase of intensities and spectral widths of absorption lines, together with a red shift of the K-edge, was shown.

  9. Electrical properties of undoped zinc oxide nanostructures at different annealing temperature

    NASA Astrophysics Data System (ADS)

    Nasir, M. F.; Zainol, M. N.; Hannas, M.; Mamat, M. H.; Rahman, S. A.; Rusop, Mohamad

    2016-07-01

    This project has been focused on the electrical and optical properties respectively on the effect of Undoped zinc oxide (ZnO) thin films at different annealing temperature which is varied 400 °C, 450 °C, 500 °C, and 550 °C.Undoped ZnO solutions were deposited onto the glass substrates using sol-gel spin coating method. This project was involved with three phases, which are thin films preparation, deposition and characterization. The thin films were characterized using Current Voltage (I-V) measurement and UV-vis-NIR spectrophotometer for electrical properties and optical properties. The electrical properties show that the resistivity is the lowest at 500 °C which its resistivity is 5.36 × 104 Ωcm-1. The absorption coefficient spectrum obtained from UV-Vis-NIR spectrophotometer measurement shows all films exhibit very low absorption in the visible (400-800nm) and near infrared (NIR) (>800nm) range but exhibit high absorption in the UV range.

  10. Study of structural and transport properties of argon, krypton, and their binary mixtures at different temperatures.

    PubMed

    Ghimire, Sunil; Adhikari, Narayan Prasad

    2017-03-01

    Molecular dynamics simulation of argon, krypton, and their binary mixtures were performed at different temperatures and constant pressure (P = 1.013 bar) using GROMACS - Groningen Machine for Chemical Simulations. The gases are modeled by Lennard-Jones pair potential, with parameters taken from the literature. The study of radial distribution functions (RDFs) shows a single peak which indicates that there is no packing effect in gaseous state for argon, krypton, and their binary mixtures. The self-diffusion coefficients of argon and krypton is determined by using mean-square displacement(MSD) method and the mutual diffusion coefficients of binary mixtures are determined using Darken's relation. The values of simulated diffusion coefficients are compared with their corresponding theoretical values, numerical estimation, and experimental data. A good agreement between these sets of data is found. The diffusion coefficients obey Arrhenius behavior to a good extent for both pure components and binary mixtures. The values of simulated diffusion coefficient are used to estimate viscosities and thermal conductivities which agree with theoretical values, numerical estimation, and experimental data within 10 %. These results support that the LJ potential is sufficient for description of molecular interactions in argon and krypton.

  11. Ontogenic changes rather than difference in temperature cause understory trees to leaf out earlier.

    PubMed

    Vitasse, Yann

    2013-04-01

    In a temperate climate, understory trees leaf out earlier than canopy trees, but the cause of this discrepancy remains unclear. This study aims to investigate whether this discrepancy results from ontogenic changes or from microclimatic differences. Seedlings of five deciduous tree species were grown in spring 2012 in the understory and at canopy height using a 45-m-high construction crane built into a mature mixed forest in the foothills of the Swiss Jura Mountains. The leaf development of these seedlings, as well as conspecific adults, was compared, taking into account the corresponding microclimate. The date of leaf unfolding occurred 10-40 d earlier in seedlings grown at canopy level than in conspecific adults. Seedlings grown in the understory flushed c. 6 d later than those grown at canopy height, which can be attributed to the warmer temperatures recorded at canopy height (c. 1°C warmer). This study demonstrates that later leaf emergence of canopy trees compared with understory trees results from ontogenic changes and not from the vertical thermal profile that exists within forests. This study warns against the assumption that phenological data obtained in warming and photoperiod experiments on juvenile trees can be used for the prediction of forest response to climate warming.

  12. An alternative method to estimate zero flow temperature differences for Granier's thermal dissipation technique.

    PubMed

    Regalado, Carlos M; Ritter, Axel

    2007-08-01

    Calibration of the Granier thermal dissipation technique for measuring stem sap flow in trees requires determination of the temperature difference (DeltaT) between a heated and an unheated probe when sap flow is zero (DeltaT(max)). Classically, DeltaT(max) has been estimated from the maximum predawn DeltaT, assuming that sap flow is negligible at nighttime. However, because sap flow may continue during the night, the maximum predawn DeltaT value may underestimate the true DeltaT(max). No alternative method has yet been proposed to estimate DeltaT(max) when sap flow is non-zero at night. A sensitivity analysis is presented showing that errors in DeltaT(max) may amplify through sap flux density computations in Granier's approach, such that small amounts of undetected nighttime sap flow may lead to large diurnal sap flux density errors, hence the need for a correct estimate of DeltaT(max). By rearranging Granier's original formula, an optimization method to compute DeltaT(max) from simultaneous measurements of diurnal DeltaT and micrometeorological variables, without assuming that sap flow is negligible at night, is presented. Some illustrative examples are shown for sap flow measurements carried out on individuals of Erica arborea L., which has needle-like leaves, and Myrica faya Ait., a broadleaf species. We show that, although DeltaT(max) values obtained by the proposed method may be similar in some instances to the DeltaT(max) predicted at night, in general the values differ. The procedure presented has the potential of being applied not only to Granier's method, but to other heat-based sap flow systems that require a zero flow calibration, such as the Cermák et al. (1973) heat balance method and the T-max heat pulse system of Green et al. (2003).

  13. Error correction of the Normalized Difference Vegetation Index and Brightness Temperature calculated from the AVHRR observations

    NASA Astrophysics Data System (ADS)

    Rahman, Mohammed Zahidur

    This thesis investigates Normalized Difference Vegetation Index (NDVI) and Brightness Temperature (BT) stability in the NOAA/NESDIS Global Vegetation Index (GVI) data during 1982-2003. This data was collected from five NOAA series satellites. We have proposed to apply Empirical distribution function (EDF) to improve the stability of the NDVI and BT data derived from the AVHRR sensor on NOAA polar orbiting satellite. The instability of data results from orbit degradation as well as the circuit drifts over the life or a satellite. Degradation of NDVI and BT over time and shifts of NDVI and BT between the satellites was estimated China data set, for it includes a wide variety or different ecosystems represented globally. It was found that data for the years 1988, 1992, 1993, 1994, 1995 and 2000 are not stable enough compared to other years because of satellite orbit drift, AVHRR sensor degradation, and also Mt Pinatubo volcanic eruption in 1992. We assume data from NOAA-7(1982, 1983), NOAA-9 (1985, 1986), NOAA-11(1989, 1990), NOAA-14(1996, 1997), and NOAA-16 (2001, 2002) to be standard because theses satellite's equator crossing time falls between 1330 and 1500. Data from this particular period of the day maximized the value of coefficients. The crux of the proposed correction procedure consists of dividing standard year's data sets into two subsets. The subset 1(standard data correction sets) is used for correcting unstable years and then corrected data for this years compared with the standard data in the subset 2 (standard data validation sets). In this dissertation, we apply EDF to correct this deficiency of data for the affected years. We normalize or correct data by the method of empirical distribution functions compared with the standard. Using these normalized values, we estimate new NDVI and BT time series which provides NDVI and BT data for these years that match in subset 2 that is used for data validation.

  14. Social interaction and sex differences influence rat temperature circadian rhythm under LD cycles and constant light.

    PubMed

    Cambras, T; Castejón, L; Díez-Noguera, A

    2011-06-01

    Circadian rhythms produce an efficient organization of animal behaviour over the 24h day. In some species, social cues have been found to have a role as synchronizers of these rhythms. Here, the influence of social interaction on rat circadian behaviour was investigated, addressing the question of whether cohabitation would produce a delay in the appearance of arrhythmicity under constant light conditions. To this end, the circadian rhythms of male and female rat body temperature were studied for 10days under light-dark conditions, followed by 33days under constant bright light. Half of the animals were maintained in individual cages, whilst the others were maintained in larger cages in groups of three rats of the same sex. Results showed that individual circadian rhythms under 24hour light-dark (LD) cycles were more stable and with higher amplitude in grouped than in isolated animals, and higher in males than in females. During the first days under constant light (LL), the stability of the rhythm was also higher in males than in females, but there were no differences according to the group. Moreover, we did not find significant differences in the time of circadian rhythm loss under LL, since high individual variability was found for this variable. On the other hand, female rats living in isolation showed a delayed acrophase in the circadian rhythm under LD conditions compared with those living in groups. These results suggest that cohabitation increases the internal coherence of circadian behaviour, and could be interpreted as indicating that living in isolation may induce a level of stress that disturbs manifestation of the circadian rhythm, especially in females, which are also more reactive than males to external signals.

  15. On model differences and skill in predicting sea surface temperature in the Nordic and Barents Seas

    NASA Astrophysics Data System (ADS)

    Langehaug, H. R.; Matei, D.; Eldevik, T.; Lohmann, K.; Gao, Y.

    2017-02-01

    The Nordic Seas and the Barents Sea is the Atlantic Ocean's gateway to the Arctic Ocean, and the Gulf Stream's northern extension brings large amounts of heat into this region and modulates climate in northwestern Europe. We have investigated the predictive skill of initialized hindcast simulations performed with three state-of-the-art climate prediction models within the CMIP5-framework, focusing on sea surface temperature (SST) in the Nordic Seas and Barents Sea, but also on sea ice extent, and the subpolar North Atlantic upstream. The hindcasts are compared with observation-based SST for the period 1961-2010. All models have significant predictive skill in specific regions at certain lead times. However, among the three models there is little consistency concerning which regions that display predictive skill and at what lead times. For instance, in the eastern Nordic Seas, only one model has significant skill in predicting observed SST variability at longer lead times (7-10 years). This region is of particular promise in terms of predictability, as observed thermohaline anomalies progress from the subpolar North Atlantic to the Fram Strait within the time frame of a couple of years. In the same model, predictive skill appears to move northward along a similar route as forecast time progresses. We attribute this to the northward advection of SST anomalies, contributing to skill at longer lead times in the eastern Nordic Seas. The skill at these lead times in particular beats that of persistence forecast, again indicating the potential role of ocean circulation as a source for skill. Furthermore, we discuss possible explanations for the difference in skill among models, such as different model resolutions, initialization techniques, and model climatologies and variance.

  16. Thermal preference, thermal resistance, and metabolic rate of juvenile Chinese pond turtles Mauremys reevesii acclimated to different temperatures.

    PubMed

    Xu, Wei; Dang, Wei; Geng, Jun; Lu, Hong-Liang

    2015-10-01

    The thermal acclimatory capacity of a particular species may determine its resilience to environmental change. Evaluating the physiological acclimatory responses of economically important species is useful for determining their optimal culture conditions. Here, juvenile Chinese three-keeled pond turtles (Mauremys reevesii) were acclimated to one of three different temperatures (17, 25 or 33°C) for four weeks to assess the effects of thermal acclimation on some physiological traits. Thermal acclimation significantly affected thermal resistance, but not thermal preference, of juvenile M. reevesii. Turtles acclimated to 17°C were less resistant to high temperatures than those acclimated to 25°C and 33°C. However, turtles increased resistance to low temperatures with decreasing acclimation temperature. The acclimation response ratio of the critical thermal minimum (CTMin) was lower than that of the critical thermal maximum (CTMax) for acclimation temperatures between 17 and 25°C, but slightly higher between 25 and 33°C. The thermal resistance range (i.e., the difference between CTMax and CTMin) was widest in turtles acclimated to the intermediate temperature (25°C), and narrowest in those acclimated to low temperature (17°C). The standard metabolic rate increased as body temperature and acclimation temperature increased, and the temperature quotient (Q10) between acclimation temperatures 17 and 25°C was higher than the Q10 between 25 and 33°C. Our results suggest that juvenile M. reevesii may have a greater resistance under mild thermal conditions resembling natural environments, and better physiological performance at relatively warm temperatures.

  17. Oxidative damage in different tissues of neonatal chicks exposed to low environmental temperature.

    PubMed

    Mujahid, Ahmad; Furuse, Mitsuhiro

    2009-04-01

    Maintenance of body temperature in a cold environment is crucial for survival in homeotherms. However, we have previously reported that on exposure to low environmental temperature, neonatal chicks (Gallus gallus) show hypothermia, decreased behavioral activity, and absence of gene transcript enhancement of putative thermogenic proteins, as well as no change in mitochondrial substrate oxidation enzymes. Various metabolic abnormalities and/or tissue damage may also decline the thermogenic capacity of low-temperature-exposed neonatal chicks. Therefore, to investigate oxidative damage in low-temperature-exposed (20 degrees C for 12 h) neonatal chicks, we studied lipid peroxidation when compared to the control chicks kept at thermoneutral temperature (30 degrees C). Malondialdehyde (MDA), was measured in plasma, brain, heart, liver and skeletal muscle (pectoralis superficialis and gastrocnemius). Weight gain and feed consumption did not change when chicks were exposed to low-temperature as compared to that of control chicks. On low-temperature exposure, body temperature was significantly decreased and plasma non-esterified fatty acid level was 1.3-fold higher than that of control chicks. In low-temperature exposed chicks, brain and heart MDA levels were 2.1- and 1.2-fold higher, respectively, than that of control chicks. This increase in MDA levels was not observed in plasma, liver and muscle of low-temperature-exposed chicks. In conclusion, there is evidence of increased lipid peroxidation in brain and heart of neonatal chicks exposed to low-temperature. We hypothesize that this oxidative damage in brain and heart may contribute to the impaired physiological, behavioral and thermoregulatory responses that potentiate the sensitivity to cold exposure.

  18. Temperature effect on proliferation and differentiation of satellite cells from turkeys with different growth rates.

    PubMed

    Clark, D L; Coy, C S; Strasburg, G M; Reed, K M; Velleman, S G

    2016-04-01

    Poultry selected for growth have an inefficient thermoregulatory system and are more sensitive to temperature extremes. Satellite cells are precursors to skeletal muscle and mediate all posthatch muscle growth. Their physiological functions are affected by temperature. The objective of the current study was to determine how temperature affects satellite cells isolated from the pectoralis major (p. major) muscle (breast muscle) of turkeys selected for increased 16 wk body weight (F line) in comparison to a randombred control line (RBC2) from which the F line originated. Pectoralis major muscle satellite cells were thermally challenged by culturing between 33°C and 43°C to analyze the effects of cold and heat on proliferation and differentiation as compared to control temperature of 38°C. Expression levels of myogenic regulatory factors: myogenic differentiation factor 1 (MYOD1) and myogenin (MYOG) were quantified by quantitative polymerase chain reaction (qPCR). At all sampling times, proliferation increased at a linear rate across temperature in both the RBC2 and F lines. Differentiation also increased at a linear rate across temperature from 33 to 41°C at all sampling times in both the F and RBC2 lines. Satellite cells isolated from F line turkeys were more sensitive to both hot and cold temperatures as proliferation and differentiation increased to a greater extent across temperature (33 to 43°C) when compared with the RBC2 line. Expression of MYOD1 and MYOG increased as temperatures increased from 33 to 41°C at all sampling times in both the F and RBC2 lines. These results demonstrate that satellite cell function is sensitive to both cold and hot temperatures and p. major muscle satellite cells from F line turkeys are more sensitive to temperature extremes than RBC2 satellite cells.

  19. Expression and Function of Different Guanine-Plus-Cytosine Content 16S rRNA Genes in Haloarcula hispanica at Different Temperatures

    PubMed Central

    Sato, Yu; Fujiwara, Taketomo; Kimura, Hiroyuki

    2017-01-01

    The halophilic archaeon Haloarcula hispanica harbors three ribosomal RNA (rRNA) operons (rrnA, rrnB, and rrnC) that contain the 16S rRNA genes rrsA, rrsB, and rrsC, respectively. Although rrsB and rrsC (rrsBC) have almost identical sequences, the rrsA and rrsBC sequences differ by 5.4%, and they differ by 2.5% with respect to guanine-plus-cytosine content (PGC). The strong correlation between the typical growth temperatures of archaea and PGC of their 16S rRNA genes suggests that H. hispanica may harbor different 16S rRNA genes having different PGC to maintain rapid growth in a wide range of temperatures. We therefore performed reverse transcription-coupled quantitative PCR to assess expression levels of rrsA (PGC, 58.9%) and rrsBC (PGC, 56.4–56.5%) at various temperatures. The expression ratio of rrsA to rrsBC increased with culture temperature. Mutants with complete deletions of one or two of the three rRNA operons were constructed and their growth rates at different temperatures compared to that of the wild-type. The growth characteristics of the rRNA operon single-mutant strains were indistinguishable from the wild-type. The rRNA operon double-mutant strains maintained the same temperature range as wild-type but displayed reduced growth rates. In particular, the double-mutant strains grew much slower than wild-type at low temperature related to minimum growth temperature of the wild-type. On the other hand, at physiologically high temperatures the wild-type and the double-mutant strain which harbors only rrnA with high-PGC rrsA grew significantly faster than the double-mutant strain which harbors only rrnC with low-PGC rrsC. These findings suggest the importance of 16S rRNAs transcribed from rrsA with high-PGC in maintaining rapid growth of this halophilic archaeon at raised growth temperatures.

  20. [Effects of different temperatures on the growth and energy budget of Chinese shrimp, Fenneropenaeus chinensis].

    PubMed

    Tian, Xiangli; Dong, Shuanglin; Wang, Fang

    2004-04-01

    The effect of temperature on the growth and energy budget of Chinese shrimp Fenneropenaeus chinensis was studied at 18, 22, 25, 28, 31 and 34 degrees C. The results showed that its specific growth rate in terms of body weight and energy accumulation increased with temperature between 18 degrees C and 31 degrees C, and then decreased significantly at 34 degrees C. The similar trend was observed in food consumption and apparent digestion rate. The food conversion efficiency in weight and energy were 28.99%-53.09% and 15.70%-7.24%, respectively, which decreased with increasing temperature. The optimum temperature for the growth of shrimp was calculated from the relationship of SGR, which was 29.7 degrees C in this study. The energy budget of shrimp showed that the energy assimilated from food decreased with increasing temperature, while that spent in metabolism increased with increasing temperature. The results indicated that the high growth rate of Chinese shrimp at suitable temperature mainly resulted from the significant increase of food consumption and apparent digestion rate at corresponding temperature regimes.

  1. Densities of mixtures containing n-alkanes with sunflower seed oil at different temperatures

    SciTech Connect

    Gonzalez, C.; Resa, J.M.; Ruiz, A.; Gutierrez, J.I.

    1996-07-01

    Densities for mixtures containing sunflower seed oil with pentane, hexane, heptane, and octane have been determined at various temperatures between 298.15 K and 313.15 K using a vibrating tube densimeter. The derived excess volumes have been correlated by the Redlich-Kister equation. All the systems showed negative deviations from ideality. The excess volumes increased with an increase in temperature.

  2. Cell response of Antarctic and temperate strains of Penicillium spp. to different growth temperature.

    PubMed

    Gocheva, Yana G; Krumova, Ekaterina Tz; Slokoska, Lyudmila S; Miteva, Jeny G; Vassilev, Spassen V; Angelova, Maria B

    2006-11-01

    The effect of growth temperature (10, 15, 20, 25, and 30 degrees C) on the cell response was compared between two Antarctic Penicillium sp. strains (Penicillium sp. p14 and Penicillium sp. m12) and a European temperate strain, Penicillium sp. t35. According to the temperature profiles, Penicillium sp. p14 was identified as psychrophilic, while Penicillium sp. m12 and Penicillium sp. t35 as mesophilic fungi, respectively. The results demonstrated that the growth at low temperature does clearly induce oxidative stress events in all strains tested. Decreases in growth temperature below the optimal coincided with markedly enhanced protein carbonyl content, an indicator of oxidatively damaged proteins. Also, the cellular response to growth temperature in terms of reserve carbohydrate was determined. In the mesophilic strains there was essentially no enhancement of glycogen content. This was in contrast to the psychrophilic Penicillium sp. p14, which gradually accumulated glycogen in response to cold (10 degrees C) during the exponential phase. In addition, elevated endogenous levels of trehalose upon low-temperature stress were exhibited by all model microorganisms. Compared with temperate mesophilic Penicillium sp. t35, Antarctic strains (psychrophilic Penicillium sp. p14 and mesophilic Penicillium sp. m12) demonstrated a marked rise in activities of protective enzymes such as superoxide dismutase and catalase at decreasing temperatures. The results suggested that low-temperature resistance is partially associated with enhanced scavenging systems.

  3. A Student-Constructed Galvanic Cell for the Measurement of Cell Potentials at Different Temperatures

    ERIC Educational Resources Information Center

    Jakubowska, Anna

    2016-01-01

    A student-made galvanic cell is proposed for temperature measurements of cell potential. This cell can be easily constructed by students, the materials needed are readily available and nontoxic, and the solution applied is in an attractive color. For this cell, the potential values are excellently reproducible at each temperature, and the…

  4. Subtle temperature differences may well determine who wins: a story of three submerged aquatic plant species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    As temperatures increases globally, shifts in the distribution of plant species are expected, with unknown effects on invasive species abundance. It is then of value to understand the role increased temperature may have on invasive species. Although nonhomeothermic organisms are the mercy of environ...

  5. Changes in Temperature Sensitivity and Activation Energy of Soil Organic Matter Decomposition in Different Qinghai-Tibet Plateau Grasslands

    PubMed Central

    Li, Jie; He, Nianpeng; Wei, Xuehong; Gao, Yang; Zuo, Yao

    2015-01-01

    Qinghai-Tibet Plateau grasslands are unique geographical regions and store substantial soil organic matter (SOM) in the soil surface, which make them very sensitive to global climate change. Here, we focused on three main grassland types (alpine meadow, steppe, and desert) and conducted a soil incubation experiment at five different temperatures (5, 10, 15, 20, and 25°C) to investigate SOM decomposition rates (R), temperature sensitivity (Q10), and activation energy (Ea). The results showed that grassland type and incubation temperature had significant impact on R (P < 0.001), and the values of R were exponential correlated with incubation temperature in three alpine grasslands. At the same temperature, R was in the following order: alpine meadow > alpinesteppe > alpine desert. The Q10 values differed significantly among different grasslands, and the overall trends were as follows: alpine meadow (1.56 ± 0.09) < alpine steppe (1.88 ± 0.23) < alpine desert (2.39 ± 0.32). Moreover, the Ea values differed significantly across different grassland types (P < 0.001) and increased with increasing incubation time. The exponential negative correlations between Ea and R at 20°C across all grassland types (all Ps < 0.001) indicated that the substrate-quality temperature hypothesis is applicable to the alpine grasslands. Our findings provide new insights for understanding the responses of SOM decomposition and storage to warming scenarios in this Plateau. PMID:26176705

  6. Changes in Temperature Sensitivity and Activation Energy of Soil Organic Matter Decomposition in Different Qinghai-Tibet Plateau Grasslands.

    PubMed

    Li, Jie; He, Nianpeng; Wei, Xuehong; Gao, Yang; Zuo, Yao

    2015-01-01

    Qinghai-Tibet Plateau grasslands are unique geographical regions and store substantial soil organic matter (SOM) in the soil surface, which make them very sensitive to global climate change. Here, we focused on three main grassland types (alpine meadow, steppe, and desert) and conducted a soil incubation experiment at five different temperatures (5, 10, 15, 20, and 25°C) to investigate SOM decomposition rates (R), temperature sensitivity (Q10), and activation energy (Ea). The results showed that grassland type and incubation temperature had significant impact on R (P < 0.001), and the values of R were exponential correlated with incubation temperature in three alpine grasslands. At the same temperature, R was in the following order: alpine meadow > alpinesteppe > alpine desert. The Q10 values differed significantly among different grasslands, and the overall trends were as follows: alpine meadow (1.56 ± 0.09) < alpine steppe (1.88 ± 0.23) < alpine desert (2.39 ± 0.32). Moreover, the Ea values differed significantly across different grassland types (P < 0.001) and increased with increasing incubation time. The exponential negative correlations between Ea and R at 20°C across all grassland types (all Ps < 0.001) indicated that the substrate-quality temperature hypothesis is applicable to the alpine grasslands. Our findings provide new insights for understanding the responses of SOM decomposition and storage to warming scenarios in this Plateau.

  7. Titanium defect structure change after gas-phase hydrogenation at different temperatures and cooling rates

    NASA Astrophysics Data System (ADS)

    Mikhaylov, Andrey A.; Laptev, Roman S.; Kudiiarov, Viktor N.; Volokitina, Tatiana L.

    2016-11-01

    Influence of gas-phase hydrogenation temperature and cooling rate on defect structure of commercially pure titanium alloy was experimentally studied by means of positron annihilation spectroscopy. The change of temperature in the process of gas-phase hydrogenation was in the range of 500-700°C, while the change of cooling rate was in the range of 0.4-10.4°C/min. With increasing of gas-phase hydrogenation temperature, significant increase of hydrogen sorption rate was found. High temperature gas-phase hydrogenation of commercially pure titanium alloy lead to the formation of vacancy and hydrogen-vacancy complexes. For the same concentration of hydrogen, temperature variation or variation of cooling rate had no effect on the type of defect. However, this variation provides significant changes in defect concentration.

  8. Long-term water temperature reconstructions from mountain lakes with different catchment and morphometric features

    PubMed Central

    Luoto, Tomi P.; Nevalainen, Liisa

    2013-01-01

    Long-term water temperature records are necessary for better understanding climate change impacts on freshwaters. We reconstruct summer water temperatures from three climatically sensitive mountain lakes in Austria using paleolimnological methods aiming to examine long-term thermal dynamics and lakes' responses to regional climate variability since the Little Ice Age. Our results indicate divergent trends for the lakes. In two of the lakes, which are located at the sunny southern slope of mountains, water temperature has increased several degrees concurrent with the observed air temperature increase. In contrast, no change is observed in the reconstructed water temperatures of a shaded lake, located at the northern slope, where also the ecological and thermal changes are most subtle. The results indicate the importance of cold water inputs, such as snowmelt and groundwater, on lakes' thermal conditions and suggest that watershed characteristics and lake stratification play a major role in defining the lake-specific thermal regime. PMID:23965988

  9. Effect of biochar produced at different pyrolysis temperature on the soil respiration of abandoned mine soil

    NASA Astrophysics Data System (ADS)

    Kim, Yong Seong; Kim, Juhee; Hwang, Wonjae; Hyun, Seunghun

    2015-04-01

    infrared gas sensor, and these data were sent to a data logger. During the measuring periods, the cumulative CO2 emission were similar between the control (516.8 mg-CO2 kg-1-soil) and BC4 5% mixture (519.3 mg-CO2 kg-1-soil), while BC7 5% mixture was significantly decreased (356.1 mg-CO2 kg-1-soil) compared to other treatment and control. Because the degradation rate of biochar generally increased with decreasing pyrolysis temperature, this result suggest that the soil respiration rates of biochar amended soils are affected by physico-chemical properties of biochar during early incubation periods (about 1 weeks), For example, surface properties of used biochars, which are related to adsorption of soil organic matter and CO2, have different properties with pyrolysis temperature such as specific surface area (BC4=5.08 m2g-1; BC7=260.75 m2 g-1, respectively), average pore diameter (BC4=4,673 nm; BC7=2,606 nm, respectively), and functional groups of biochar surface. However, there was not clear evidence of biochar-mine soil interaction process, because of the short observation periods. Future work should focus on the adsorption of CO2 and soil organic matter of biochar and soil-biochar interaction with long time periods and various biological test.

  10. Can we improve heterosis for root growth of maize by selecting parental inbred lines with different temperature behaviour?

    PubMed Central

    Hund, Andreas; Reimer, Regina; Stamp, Peter; Walter, Achim

    2012-01-01

    Tolerance to high and low temperature is an important breeding aim for Central and Northern Europe, where temperature fluctuations are predicted to increase. However, the extent to which genotypes differ in their response to the whole range of possible temperatures is not well understood. We tested the hypothesis that the combination of maize (Zea mays L.) inbred lines with differing temperature optima for root growth would lead to superior hybrids. This hypothesis is based on the concept of ‘marginal overdominance’ in which the hybrid expresses higher relative fitness than its parents, summed over all situations. The elongation rates of axile and lateral roots of the reciprocal cross between two flint and two dent inbred lines were assessed at temperatures between 15°C and 40°C. Indeed, the cross between UH005 and UH250 with lateral root growth temperature optima at 34°C and 28°C, respectively, resulted in intermediate hybrids. At temperatures below and above 31°C, the hybrids' root growth was comparable to the better parent, respectively, thereby increasing temperature tolerance of the hybrid compared with its parents. The implications of and reasons for this heterosis effect are discussed in the context of breeding for abiotic stress tolerance and of putatively underlying molecular mechanisms. This finding paves the way for more detailed investigations of this phenomenon in future studies. PMID:22527401

  11. Verrucarin A and roridin E produced on spinach by Myrothecium verrucaria under different temperatures and CO2 levels.

    PubMed

    Siciliano, Ilenia; Bosio, Pietro; Gilardi, Giovanna; Gullino, Maria Lodovica; Garibaldi, Angelo

    2017-03-09

    The behavior of Myrothecium verrucaria, artificially inoculated on spinach, was studied under seven different temperature conditions (from 5 to 35 °C) and under eight different combinations of temperature and CO2 concentration (14-30 °C and 775-870 or 1550-1650 mg/m(3)). The isolate used for this study was growing well on spinach, and the mycotoxins verrucarin A and roridin E were produced under all tested temperature and CO2 conditions. The maximum levels of verrucarin A (18.59 ng/g) and roridin E (49.62 ng/g) were found at a temperature of 26-30 °C and a CO2 level of 1550-1650 mg/m(3). Rises in temperature as well as in temperature and CO2 concentrations had a significant effect by increasing Myrothecium leaf spots on spinach. The biosynthesis of verrucarin A was significantly increased at the highest temperature (35 °C), while roridin E was influenced by the CO2 concentration. These results show that a positive correlation between climate condition and macrocyclic trichothecene production is possible. However, because of the ability of M. verrucaria to produce mycotoxins, an increase in temperature could induce the spread of M. verrucaria in temperate regions; this pathogen may gain importance in the future.

  12. Can we improve heterosis for root growth of maize by selecting parental inbred lines with different temperature behaviour?

    PubMed

    Hund, Andreas; Reimer, Regina; Stamp, Peter; Walter, Achim

    2012-06-05

    Tolerance to high and low temperature is an important breeding aim for Central and Northern Europe, where temperature fluctuations are predicted to increase. However, the extent to which genotypes differ in their response to the whole range of possible temperatures is not well understood. We tested the hypothesis that the combination of maize (Zea mays L.) inbred lines with differing temperature optima for root growth would lead to superior hybrids. This hypothesis is based on the concept of 'marginal overdominance' in which the hybrid expresses higher relative fitness than its parents, summed over all situations. The elongation rates of axile and lateral roots of the reciprocal cross between two flint and two dent inbred lines were assessed at temperatures between 15°C and 40°C. Indeed, the cross between UH005 and UH250 with lateral root growth temperature optima at 34°C and 28°C, respectively, resulted in intermediate hybrids. At temperatures below and above 31°C, the hybrids' root growth was comparable to the better parent, respectively, thereby increasing temperature tolerance of the hybrid compared with its parents. The implications of and reasons for this heterosis effect are discussed in the context of breeding for abiotic stress tolerance and of putatively underlying molecular mechanisms. This finding paves the way for more detailed investigations of this phenomenon in future studies.

  13. A unified degree day model describes survivorship of Copitarsia corruda Pogue & Simmons (Lepidoptera: Noctuidae) at different constant temperatures.

    PubMed

    Gómez, N N; Venette, R C; Gould, J R; Winograd, D F

    2009-02-01

    Predictions of survivorship are critical to quantify the probability of establishment by an alien invasive species, but survival curves rarely distinguish between the effects of temperature on development versus senescence. We report chronological and physiological age-based survival curves for a potentially invasive noctuid, recently described as Copitarsia corruda Pogue & Simmons, collected from Peru and reared on asparagus at six constant temperatures between 9.7 and 34.5 degrees C. Copitarsia spp. are not known to occur in the United States but are routinely intercepted at ports of entry. Chronological age survival curves differ significantly among temperatures. Survivorship at early age after hatch is greatest at lower temperatures and declines as temperature increases. Mean longevity was 220 (+/-13 SEM) days at 9.7 degrees C. Physiological age survival curves constructed with developmental base temperature (7.2 degrees C) did not correspond to those constructed with a senescence base temperature (5.9 degrees C). A single degree day survival curve with an appropriate temperature threshold based on senescence adequately describes survivorship under non-stress temperature conditions (5.9-24.9 degrees C).

  14. Isotopic ordering in eggshells reflects body temperatures and suggests differing thermophysiology in two Cretaceous dinosaurs.

    PubMed

    Eagle, Robert A; Enriquez, Marcus; Grellet-Tinner, Gerald; Pérez-Huerta, Alberto; Hu, David; Tütken, Thomas; Montanari, Shaena; Loyd, Sean J; Ramirez, Pedro; Tripati, Aradhna K; Kohn, Matthew J; Cerling, Thure E; Chiappe, Luis M; Eiler, John M

    2015-10-13

    Our understanding of the evolutionary transitions leading to the modern endothermic state of birds and mammals is incomplete, partly because tools available to study the thermophysiology of extinct vertebrates are limited. Here we show that clumped isotope analysis of eggshells can be used to determine body temperatures of females during periods of ovulation. Late Cretaceous titanosaurid eggshells yield temperatures similar to large modern endotherms. In contrast, oviraptorid eggshells yield temperatures lower than most modern endotherms but ∼ 6 °C higher than co-occurring abiogenic carbonates, implying that this taxon did not have thermoregulation comparable to modern birds, but was able to elevate its body temperature above environmental temperatures. Therefore, we observe no strong evidence for end-member ectothermy or endothermy in the species examined. Body temperatures for these two species indicate that variable thermoregulation likely existed among the non-avian dinosaurs and that not all dinosaurs had body temperatures in the range of that seen in modern birds.

  15. Age-stage, two-sex life table of Parapoynx crisonalis (Lepidoptera: Pyralidae) at different temperatures

    PubMed Central

    Chen, Qi; Li, Ni; Wang, Xing; Ma, Li; Huang, Jian-Bin; Huang, Guo-Hua

    2017-01-01

    Parapoynx crisonalis is an important pest of many aquatic vegetables including water chestnuts. Understanding the relationship between temperature variations and the population growth rates of P. crisonalis is essential to predicting its population dynamics in water chestnuts ponds. These relationships were examined in this study based on the age-stage, two-sex life table of P. crisonalis developed in the laboratory at 21, 24, 27, 30, 33 and 36°C. The results showed that the values of Sxj (age-stage–specific survival rate), fxj (age-stage-specific fecundity), lx (age specific survival rate) and mx (age-specific fecundity) increased as the temperature rose from 21 to 27°C, then decreased from 30 to 36°C. Temperature also had a significant effect on the net reproductive rate (R0), gross reproductive rate (GRR), intrinsic rate of increase (r) and finite rate of increase (λ). The value of these parameters were at low levels at 21, 33, and 36°C. Further, the r value decreased as the temperature rose from 24 to 30°C, while the GRR reached its highest level at 27°C. The results indicated that optimal growth and development of P. crisonalis occurred at temperatures between 24°C to 30°C when compared to the lowest temperature (21°C) and higher temperatures of 33°C and 36°C. PMID:28264022

  16. Pathogenicity of Choristoneura fumiferana nucleopolyhedrovirus propagated in vitro at different incubation temperatures.

    PubMed

    Ebling, Peter M; Caputo, Guido F; Cook, Barbara J

    2003-01-01

    To optimize the in vitro production of Choristoneura fumiferana nucleopolyhedrovirus (CfMNPV) as a potential microbial pest control agent, the pathogenicity of occlusion bodies (OBs) produced in two cell lines at three incubation temperatures was determined by bioassay. A plaque-purified isolate of CfMNPV was amplified in permissive C. fumiferana cell lines, FPMI-CF-203 and FPMI-CF-2C1, and incubated at 22, 24, and 28 degrees C. Occlusion bodies propagated in FPMI-CF-203 cells at 28 degrees C were significantly larger (17.5 microm(3)) and more pathogenic (LD(50) = 27; LD(95) = 185, where LD(50) and LD(95) are doses required to kill 50 and 95% of the test larvae, respectively) than those produced in either of the cell lines at any of the incubation temperatures tested. Increased temperatures yielded larger OBs from both cell lines. The pathogenicity of OBs propagated in the FPMI-CF-203 cell line increased with incubation temperature, whereas that of OBs produced in FPMI-CF-2C1 cells decreased. Comparison of the pathogenicity of OBs, whether naturally occurring or genetically modified, should be standardized by cell line and incubation temperature used for propagation. Production efficiency decreased with increasing incubation temperature for each cell line. Lower incubation temperatures used for propagation, and standardization of the titer of viral inoculum, should be further investigated to determine the economic feasibility of the in vitro production of CfMNPV as a microbial pest control agent.

  17. Age-stage, two-sex life table of Parapoynx crisonalis (Lepidoptera: Pyralidae) at different temperatures.

    PubMed

    Chen, Qi; Li, Ni; Wang, Xing; Ma, Li; Huang, Jian-Bin; Huang, Guo-Hua

    2017-01-01

    Parapoynx crisonalis is an important pest of many aquatic vegetables including water chestnuts. Understanding the relationship between temperature variations and the population growth rates of P. crisonalis is essential to predicting its population dynamics in water chestnuts ponds. These relationships were examined in this study based on the age-stage, two-sex life table of P. crisonalis developed in the laboratory at 21, 24, 27, 30, 33 and 36°C. The results showed that the values of Sxj (age-stage-specific survival rate), fxj (age-stage-specific fecundity), lx (age specific survival rate) and mx (age-specific fecundity) increased as the temperature rose from 21 to 27°C, then decreased from 30 to 36°C. Temperature also had a significant effect on the net reproductive rate (R0), gross reproductive rate (GRR), intrinsic rate of increase (r) and finite rate of increase (λ). The value of these parameters were at low levels at 21, 33, and 36°C. Further, the r value decreased as the temperature rose from 24 to 30°C, while the GRR reached its highest level at 27°C. The results indicated that optimal growth and development of P. crisonalis occurred at temperatures between 24°C to 30°C when compared to the lowest temperature (21°C) and higher temperatures of 33°C and 36°C.

  18. Fungal Communities Associated with the Biodegradation of Polyester Polyurethane Buried under Compost at Different Temperatures

    PubMed Central

    Zafar, Urooj; Houlden, Ashley

    2013-01-01

    Plastics play an essential role in the modern world due to their low cost and durability. However, accumulation of plastic waste in the environment causes wide-scale pollution with long-lasting effects, making plastic waste management expensive and problematic. Polyurethanes (PUs) are heteropolymers that made up ca. 7% of the total plastic production in Europe in 2011. Polyester PUs in particular have been extensively reported as susceptible to microbial biodegradation in the environment, particularly by fungi. In this study, we investigated the impact of composting on PUs, as composting is a microbially rich process that is increasingly being used for the processing of green waste and food waste as an economically viable alternative to landfill disposal. PU coupons were incubated for 12 weeks in fresh compost at 25°C, 45°C, and 50°C to emulate the thermophilic and maturation stages of the composting process. Incubation at all temperatures caused significant physical deterioration of the polyester PU coupons and was associated with extensive fungal colonization. Terminal restriction fragment length polymorphism (TRFLP) analysis and pyrosequencing of the fungal communities on the PU surface and in the surrounding compost revealed that the population on the surface of PU was different from the surrounding compost community, suggesting enrichment and selection. The most dominant fungi identified from the surfaces of PU coupons by pyrosequencing was Fusarium solani at 25°C, while at both 45°C and 50°C, Candida ethanolica was the dominant species. The results of this preliminary study suggest that the composting process has the potential to biodegrade PU waste if optimized further in the future. PMID:24056469

  19. Fungal communities associated with the biodegradation of polyester polyurethane buried under compost at different temperatures.

    PubMed

    Zafar, Urooj; Houlden, Ashley; Robson, Geoffrey D

    2013-12-01

    Plastics play an essential role in the modern world due to their low cost and durability. However, accumulation of plastic waste in the environment causes wide-scale pollution with long-lasting effects, making plastic waste management expensive and problematic. Polyurethanes (PUs) are heteropolymers that made up ca. 7% of the total plastic production in Europe in 2011. Polyester PUs in particular have been extensively reported as susceptible to microbial biodegradation in the environment, particularly by fungi. In this study, we investigated the impact of composting on PUs, as composting is a microbially rich process that is increasingly being used for the processing of green waste and food waste as an economically viable alternative to landfill disposal. PU coupons were incubated for 12 weeks in fresh compost at 25°C, 45°C, and 50°C to emulate the thermophilic and maturation stages of the composting process. Incubation at all temperatures caused significant physical deterioration of the polyester PU coupons and was associated with extensive fungal colonization. Terminal restriction fragment length polymorphism (TRFLP) analysis and pyrosequencing of the fungal communities on the PU surface and in the surrounding compost revealed that the population on the surface of PU was different from the surrounding compost community, suggesting enrichment and selection. The most dominant fungi identified from the surfaces of PU coupons by pyrosequencing was Fusarium solani at 25°C, while at both 45°C and 50°C, Candida ethanolica was the dominant species. The results of this preliminary study suggest that the composting process has the potential to biodegrade PU waste if optimized further in the future.

  20. Breakdown voltage and triggering probability of SiPM from IV curves at different temperatures

    NASA Astrophysics Data System (ADS)

    Dinu, N.; Nagai, A.; Para, A.

    2017-02-01

    This work presents a physical model describing the IV curves of SiPM detectors allowing to easily determine important device parameters like breakdown voltage VBD and the shape of Geiger triggering probability PGeiger. We measured IV curves and tested our IV model in a temperature range - 35 ° C < T < + 35 ° C on various SiPMs from two vendors (Hamamatsu devices of 3 × 3mm2 total area and 50 × 50 μm2 μcell size, 2011 and 2015 year production runs and KETEK devices of 0.5 × 0.5mm2 total area and 50 × 50 μm2 μcell size, 2015 production run). The shape of IV curve can be described in terms of Geiger probability and afterpulsing in a very large current range of 10-12 A difference in the physical significance of the "breakdown voltage" determined by these two methods. The recent generation of SiPMs have very wide working range and there is an evidence phenomena beyond afterpulsing like heating or non-quenched pulses contributing to the fast increase of the current at high bias voltages.

  1. Natural populations of Arabidopsis thaliana differ in seedling responses to high-temperature stress

    PubMed Central

    Zhang, Nana; Belsterling, Brian; Raszewski, Jesse; Tonsor, Stephen J.

    2015-01-01

    Little is known about adaptive within-species variation in thermotolerance in wild plants despite its likely role in both functional adaptation at range limits and in predicting response to climate change. Heat shock protein Hsp101, rapidly heat induced in Arabidopsis thaliana, plays a central role in thermotolerance in laboratory studies, yet little is known about variation in its expression in natural populations. We explored variation in thermotolerance and Hsp101 expression in seedlings from 16 natural populations of A. thaliana sampled along an elevation and climate gradient. We tested both naive controls (maintained at 22 °C until heat stress) and thermally pre-acclimated plants (exposed to a 38 °C 3-h acclimation treatment). After acclimation, seedlings were exposed to one of two heat stresses: 42 or 45 °C. Thermotolerance was measured as post-stress seedling survival and root growth. When stressed at 45 °C, both thermotolerance and Hsp101 expression were significantly increased by pre-acclimation. However, thermotolerance did not differ between pre-acclimation and control when followed by a 42 °C stress. Immediately after heat stress, pre-acclimated seedlings contained significantly more Hsp101 than control seedlings. At 45 °C, Hsp101 expression was positively associated with survival (r2 = 0.37) and post-stress root growth (r2 = 0.15). Importantly, seedling survival, post-stress root growth at 45 °C and Hsp101 expression at 42 °C were significantly correlated with the home sites' first principal component of climate variation. This climate gradient mainly reflects a temperature and precipitation gradient. Thus, the extent of Hsp101 expression modulation and thermotolerance appear to be interrelated and to evolve adaptively in natural populations of A. thaliana. PMID:26286225

  2. Effect of the lipid regulator Gemfibrozil in the Cladocera Daphnia magna at different temperatures.

    PubMed

    Salesa, Beatriz; Ferrando, María D; Villarroel, María J; Sancho, Encarna

    2017-02-23

    In the present study, an ecotoxicological approach to the evaluation of Gemfibrozil (GEM) as an emerging organic pollutant was done. In order to assess its toxicity, tests were conducted using the cladocera Daphnia magna. Experiments were carried out at 22°C and 28°C. EC50, feeding behavior, and chronic toxicity tests (21 days) were evaluated in D. magna exposed to GEM as well as cholesterol levels at 21-day chronic exposure. D. magna GEM EC50 values (24 h) in our experimental conditions were 148.75 and 116.24 mg L(-1) at 22°C and 28°C, respectively. Test concentrations of 0.1, 0.5, 1.0, 5.0 and 7.5 mg L(-1) were selected for subacute and chronic experiments. Subacute short-term test (feeding study) was assessed after exposure to the toxicant. Filtration and ingestion rates of D. magna exposed animals did not show any significant difference (P > 0.05) with respect to control daphniids neither at 22°C nor at 28°C. Therefore, GEM test concentrations used in the present study did not reduce feeding behavior in D. magna. Temperature increased from 22°C to 28°C, which resulted in a decrease of the daphniids reproductive parameters such as brood size and number of young per female. Other parameters as longevity were not affected. The GEM concentrations used in the chronic test with D. magna did not affect daphniids longevity but some reproductive parameters as number of young per female or brood size were affected. Finally, a significant decreased in cholesterol levels was found in those animals exposed to the highest toxicant concentrations. More studies must be done to determine the possible implications of GEM in aquatic fauna and to derive its possible effects on the environment.

  3. [Thermocompensatory reactions of rabbits in response to microwave irradiation at different environmental temperatures].

    PubMed

    Kolganova, O I; Zhavronkov, L P; Petin, V G; Drozd, A I; Glushakova, V S; Panferova, T A

    2001-01-01

    Thermogenic effectiveness of electromagnetic irradiation (EMI) of UHF range (7 GHz) in the dependence on intensity (10-100 mW/cm2) and environmental temperature was studied in experiments with rabbits. Synergistic interaction of EMI and high ambient temperature was established. The existence of optimal EMI and high ambient temperature was established. The existence of optimal EMI intensity at which the synergy was maximal was shown. It is concluded that this interaction should be taken into account for hygienic standardization of nonionizing EMI.

  4. Nest-building in gray short-tailed opossums: temperature effects and sex differences.

    PubMed

    Fadem, B H; Kraus, D B; Sheffet, R H

    1986-01-01

    The effects of ambient temperature and of sex on nest-building behavior were studied in a laboratory colony of gray short-tailed opossums, small, Brazilian marsupials. At 24 degrees C, both males and females used more nesting material and built larger nests of better quality than at 27 degrees C. Although both males and females built nests using the mouth, forelegs, hindlegs and tail, females built nests more reliably at the higher temperature and used more nesting material than males at both temperatures. These findings are discussed with respect to the thermoregulatory and reproductive characteristics of marsupials.

  5. Long-term rearing of Arctic charr Salvelinus alpinus under different salinity regimes at constant temperature.

    PubMed

    Arnason, T; Gunnarsson, S; Imsland, A K; Thorarensen, H; Smáradóttir, H; Steinarsson, A; Gústavsson, A; Johansson, M; Björnsson, B Th

    2014-10-01

    Arctic charr Salvelinus alpinus of the Hólar strain (mean ± s.e. body mass = 152·1 ± 3·1 g) were reared at four different salinity regimes at a constant temperature of 7·4° C. Two groups were given a three-month acclimation in salinity 18 before the salinity was increased to either 25 or 29 (groups called A25 and A29), and two groups were reared in salinities 25 or 29 over the full experimental period of 409 days (groups called F25 and F29). In the first 3 months, the A25 and A29 groups had the highest growth rates. By October 2011, there were no significant differences (two-way nested ANOVA, P > 0·05) in the mean body masses among A25, F25 and F29 (c. 1450 g), whereas A29 had a lower mean mass (1282 g). The growth in the last period from October 2011 to January 2012 was reduced by sexual maturation in the highest salinity regimes (A29 and F29), whereas fish in groups A25 and F25 showed high growth throughout the study. Males in all salinity groups had higher growth rates than females for the most part of the study, but the divergence between the sexes was most pronounced in the highest salinity regimes. All salinity groups showed distinct changes in Na(+) , K(+) -ATPase activity, with high activity in spring and summer, and lower activity in the autumn. Plasma sodium (Na(+) ) levels were stable indicating that none of the experimental groups had problems in maintaining hydromineral balance during the study. While plasma leptin levels were not affected by salinity regimes, it was noted that these levels were 13-30% higher in fish with empty guts compared with those having food in their gut at the time of sampling. This suggests a link between leptin levels and food intake, indicating that this hormone may play a role in food intake and energy allocation in fishes.

  6. Growth and biopigment accumulation of cyanobacterium Spirulina platensis at different light intensities and temperature

    PubMed Central

    Kumar, Manoj; Kulshreshtha, Jyoti; Singh, Gajendra Pal

    2011-01-01

    In order to find out optimum culture condition for algal growth, the effect of light irradiance and temperature on growth rate, biomass composition and pigment production of Spirulina platensis were studied in axenic batch cultures. Growth kinetics of cultures showed a wide range of temperature tolerance from 20 °C to 40 °C. Maximum growth rate, cell production with maximum accumulation of chlorophyll and phycobilliproteins were found at temperature 35 °C and 2,000 lux light intensity. But with further increase in temperature and light intensity, reduction in growth rate was observed. Carotenoid content was found maximum at 3,500 lux. Improvement in the carotenoid content with increase in light intensity is an adaptive mechanism of cyanobacterium S.platensis for photoprotection, could be a good basis for the exploitation of microalgae as a source of biopigments. PMID:24031731

  7. Low-temperature production of silicon carbide films of different polytypes

    SciTech Connect

    Semenov, A. V. Puzikov, V. M.; Golubova, E. P.; Baumer, V. N.; Dobrotvorskaya, M. V.

    2009-05-15

    The study is concerned with the effect of temperature on the structure of SiC films formed by deposition of the C and Si ions with the energy 120 eV. On the basis of the X-ray structural studies, it is unambiguously established that the structure of the growing polytype is finely dependent on the substrate temperature. In the temperature range from 1080 deg. C to 1510 deg. C, the sequence of films involving the 21R, 51R, 27R, and 6H polytypes is produced for the first time. The effect of temperature on the silicon-carbon atomic content ratio [Si]/[C] in the deposited films is determined. At optimized parameters of deposition the film structured as the 51R rhombohedral polytype is grown.

  8. [Effects of temperature on organic carbon mineralization in paddy soils with different clay content].

    PubMed

    Ren, Xiu-E; Tong, Cheng-Li; Sun, Zhong-Lin; Tang, Guo-Yong; Xiao, He-Ai; Wu, Jin-Shui

    2007-10-01

    An incubation test with three kinds of paddy soil (sandy loam, clay loam, and silty clay soils) in subtropical region was conducted at 10, 15, 20, 25 and 30 degrees C to examine the response of the mineralization of soil organic carbon (SOC) to temperature change. The results showed that during the period of 160 d incubation, the accumulative mineralized amount of SOC in sandy loam, clay loam, and silty clay soils at 30 degrees C was 3.5, 5.2 and 4.7 times as much as that at 10 degrees C, respectively. The mineralization rate was lower and relatively stable at lower temperatures (< or = 20 C), but was higher at the beginning of incubation and decreased and became stable as the time prolonged at higher temperatures (> or = 25 degrees C). During incubation, the temperature coefficient (Q10) of SOC mineralization in test soils fluctuated, with an average Q10 in sandy loam, clay loam, and silty clay soils being 1.92, 2.37 and 2.32, respectively. There was a positive exponential correlation between SOC mineralization constant k and temperature (P < 0.01), and the response of SOC mineralization to temperature change was in the order of clay loam soil > silty clay soil > sandy loam soil.

  9. Physical characterization of Rhipsalis (Cactaceae) fruits and seeds germination in different temperatures and light regimes.

    PubMed

    Lone, A B; Colombo, R C; Andrade, B L G; Takahashi, L S A; Faria, R T

    2016-06-01

    The germination characteristics of the native cactus species are poorly known, being the temperature and the light the factors that the most interferes in that process. Thus, the objective of the present work was to characterize the fruits and evaluate the influence of the temperature and the light in the seed germination of Rhipsalis floccosa, Rhipsalis pilocarpa and Rhipsalis teres. The tested constant temperatures were 15, 20, 25, 30 and 35 °C and the alternate of 20-30 °C and 25-35 °C in a photoperiod of 10 hours, and with determination of the most appropriate temperature, the germination was tested in light absence. The germination percentage, the index of germination speed and medium time of germination were evaluated. For R. floccosa, the highest germination percentage was at 20 °C. For R. pilocarpa and R. teres, the highest germination percentages occurred in 15 °C and 20 °C. There was correlation to germination percentage between the three species, indicating that they had similar germination behavior. Total absence of germination was verified for the three species in condition of light absence. In conclusion, the temperature of 20 °C is the most suitable for the seed germination of R. floccosa. For the species R. pilocarpa and R. teres, the temperatures of 15 and 20 °C are the most suitable.

  10. Investigation of effective base transit time and current gain modulation of light-emitting transistors under different ambient temperatures

    SciTech Connect

    Yang, Hao-Hsiang; Tu, Wen-Chung; Wang, Hsiao-Lun; Wu, Chao-Hsin

    2014-11-03

    In this report, the modulation of current gain of InGaP/GaAs light-emitting transistors under different ambient temperatures are measured and analyzed using thermionic emission model of quantum well embedded in the transistor base region. Minority carriers captured by quantum wells gain more energy at high temperatures and escape from quantum wells resulting in an increase of current gain and lower optical output, resulting in different I-V characteristics from conventional heterojunction bipolar transistors. The effect of the smaller thermionic lifetime thus reduces the effective base transit time of transistors at high temperatures. The unique current gain enhancement of 27.61% is achieved when operation temperature increase from 28 to 85 °C.

  11. Aquatic hyphomycete strains from metal-contaminated and reference streams might respond differently to future increase in temperature.

    PubMed

    Ferreira, Verónica; Gonçalves, Ana Lúcia; Canhoto, Cristina

    2012-01-01

    Aquatic hyphomycetes, a group of polyphyletic fungi, have been reported in streams contaminated with metals. This tolerance to metal contamination however can result in limited performance and limited ability to cope with additional environmental change. The predicted increase in water temperature, as a consequence of global warming, will have an additional effect on many streams. The sensitivity to temperature of strains of three aquatic hyphomycete species isolated from a metal-contaminated stream and an uncontaminated stream was assessed by determining their radial growth and activity (conidial production, oxygen consumption, mycelial biomass accumulation, fine particulate organic matter [FPOM] production, and microbial induced leaf mass loss) at 13 C (present water temperature in autumn) and at 18 C (predicted water temperature under global warming). Growth and reproductive activity generally were depressed for the strains isolated from the metal-contaminated stream when compared with those isolated from the unpolluted stream. These differences however were not translated into differences in FPOM production and leaf-litter mass loss, indicating that the strains isolated from the contaminated stream can decompose leaf litter similar to those of the reference stream. The 5 C increase in temperature stimulated fungal activity and litter decomposition, irrespective of species and strain. This might have strong effect on aquatic food-web and ecosystem functioning under global warming because increases in litter decomposition might lead to food shortage for higher trophic levels. The sensitivity to temperature depended on the response variable, species and strain. FPOM production was the variable most sensitive to temperature across strains and species and that for which temperature sensitivities differed most between strains. Fungal tolerance to metal contamination affects the extent to which its functions are stimulated by an increase in temperature, constituting

  12. Critical Temperature Differences of a Standing Wave Thermoacoustic Prime Mover with Various Helium-Based Binary Mixture Working Gases

    NASA Astrophysics Data System (ADS)

    Setiawan, Ikhsan; Nohtomi, Makoto; Katsuta, Masafumi

    2015-06-01

    Thermoacoustic prime movers are energy conversion devices which convert thermal energy into acoustic work. The devices are environmentally friendly because they do not produce any exhaust gases. In addition, they can utilize clean energy such as solar-thermal energy or waste heat from internal combustion engines as the heat sources. The output mechanical work of thermoacoustic prime movers are usually used to drive a thermoacoustic refrigerator or to generate electricity. A thermoacoustic prime mover with low critical temperature difference is desired when we intend to utilize low quality of heat sources such as waste heat and sun light. The critical temperature difference can be significantly influenced by the kinds of working gases inside the resonator and stack's channels of the device. Generally, helium gas is preferred as the working gas due to its high sound speed which together with high mean pressure will yield high acoustic power per unit volume of the device. Moreover, adding a small amount of a heavy gas to helium gas may improve the efficiency of thermoacoustic devices. This paper presents numerical study and estimation of the critical temperature differences of a standing wave thermoacoustic prime mover with various helium-based binary-mixture working gases. It is found that mixing helium (He) gas with other common gases, namely argon (Ar), nitrogen (N2), oxygen (O2), and carbon dioxide (CO2), at appropriate pressures and molar compositions, reduce the critical temperature differences to lower than those of the individual components of the gas mixtures. In addition, the optimum mole fractions of Hegas which give the minimum critical temperature differences are shifted to larger values as the pressure increases, and tends to be constant at around 0.7 when the pressure increases more than 2 MPa. However, the minimum critical temperature differences slightly increase as the pressure increases to higher than 1.5 MPa. Furthermore, we found that the lowest

  13. Effects of a glyphosate-based herbicide on the development of Common toads (Bufo bufo L.; Amphibia) at different temperatures

    NASA Astrophysics Data System (ADS)

    Baier, Fabian; Gruber, Edith; Spangl, Bernhard; Zaller, Johann G.

    2016-04-01

    Herbicides based on the active ingredient glyphosate are frequently applied in agriculture, horticulture and private gardens all over the world. Recently, leaching of glyphosate or its metabolite (AMPA) into water bodies inhabited by amphibians has been reported. However, very little is known about non-target effects of these herbicides on amphibians and even less is known to what extent different temperatures might alter these effects. Using climate chambers, we investigated the effects of the glyphosate-based herbicide Roundup PowerFlex® (480 g L-1 glyphosate, formulated as 588 g L-1 potassium salt) on the larval development of Common toads (Bufo bufo L.; Amphibia: Anura) under different temperature regimes (15°C vs. 20°C). We established five herbicide concentrations: 0, 1.5, 3, 4 mg acid equivalent L-1 and a 4 mg a.e. L-1 pulse treatment (totally three applications of 1.5, 1.5 and another 1 mg a.e. L-1) at each temperature in a full-factorial design. Each treatment combination was replicated five times, the experiment ran for 24 days. Results showed a highly significant effect of temperature on body length and body width but no effect of herbicide concentration on these growth parameters. Moreover, highly significant interactions between herbicide and temperature on body length and body width were observed suggesting that herbicides had different effects on different temperatures. In conclusion, although Roundup PowerFlex® at the tested concentrations appeared to have no acute toxicity to larvae of Common toads, the observed effects on tadpole morphology will potentially affect competitive interactions in spawning ponds of amphibia. Our findings of herbicide x temperature interactions might become more prevalent when human-induced climate change will lead to more extreme temperatures.

  14. Differences in the catalytic mechanisms of mesophilic and thermophilic indole-3-glycerol phosphate synthase enzymes at their adaptive temperatures

    SciTech Connect

    Zaccardi, Margot J.; Mannweiler, Olga; Boehr, David D.

    2012-02-10

    Highlights: Black-Right-Pointing-Pointer Catalytic mechanisms of thermophilic-mesophilic enzymes may differ. Black-Right-Pointing-Pointer Product release is rate-determining for thermophilic IGPS at low temperatures. Black-Right-Pointing-Pointer But at higher temperatures, proton transfer from the general acid is rate-limiting. Black-Right-Pointing-Pointer Rate-determining step is different still for mesophilic IGPS. Black-Right-Pointing-Pointer Both chemical and physical steps of catalysis are important for temperature adaptation. -- Abstract: Thermophilic enzymes tend to be less catalytically-active at lower temperatures relative to their mesophilic counterparts, despite having very similar crystal structures. An often cited hypothesis for this general observation is that thermostable enzymes have evolved a more rigid tertiary structure in order to cope with their more extreme, natural environment, but they are also less flexible at lower temperatures, leading to their lower catalytic activity under mesophilic conditions. An alternative hypothesis, however, is that complementary thermophilic-mesophilic enzyme pairs simply operate through different evolutionary-optimized catalytic mechanisms. In this communication, we present evidence that while the steps of the catalytic mechanisms for mesophilic and thermophilic indole-3-glycerol phosphate synthase (IGPS) enzymes are fundamentally similar, the identity of the rate-determining step changes as a function of temperature. Our findings indicate that while product release is rate-determining at 25 Degree-Sign C for thermophilic IGPS, near its adaptive temperature (75 Degree-Sign C), a proton transfer event, involving a general acid, becomes rate-determining. The rate-determining steps for thermophilic and mesophilic IGPS enzymes are also different at their respective, adaptive temperatures with the mesophilic IGPS-catalyzed reaction being rate-limited before irreversible CO{sub 2} release, and the thermophilic IGPS

  15. Use of palm mid-fraction in dark chocolate as base filling centre at different storage temperatures.

    PubMed

    Jinap, S; Ali, A A; Man, Y B; Suria, A M

    2000-11-01

    Dark chocolates filled with palm mid-fraction (PMF) were stored at different temperatures to evaluate the physical and chemical changes. Storage at low temperature (18 degrees C) reduces the PMF migration to negligible extent. Higher storage temperatures (30 and 35 degrees C) increased the PMF migration from the filling centre into the chocolate coating. As a consequence of fat migration, fatty acid composition, triglyceride composition, hardness, solid fat content, melting point and polymorphic structure changed, leading to bloom formation, which started by fat migration and was influenced by recrystallization tendency within the chocolate coating.

  16. Differences in the Temperature Sensitivity of Soil Organic Carbon Decomposition in a Semi-Arid Ecosystem across an Elevational Gradient

    NASA Astrophysics Data System (ADS)

    Delvinne, H.; Flores, A. N.; Benner, S. G.; Feris, K. P.; De Graaff, M. A.

    2015-12-01

    Semi-arid ecosystems are a significant component of the global carbon (C) cycle as they store approximately 20% of global soil C. Yet, projected increases in mean annual temperatures might alter the amount of soil organic C (SOC) currently stored in these ecosystems. Uncertainties about the temperature sensitivity of SOC decomposition have hindered accurate predictions of C cycle feedbacks to climate change. This study aims to elucidate how the temperature sensitivity of SOC decomposition varies along an elevational (1000m) and climatic (i.e. mean annual temperature and precipitation) gradient. The study sites are located at Reynolds Creek Critical Zone Observatory in Owyhee Mountains of Idaho, USA. We conducted stratified random sampling of soil up to 0-5cm across sagebrush canopy and inter-canopy areas at four elevations. We hypothesized decomposition of SOC pools at lower elevations to have greater temperature sensitivity (more CO2 respired per unit C) compared to upper due to the quality of C that is inherently more temperature sensitive. To assess the temperature sensitivity of SOC decomposition, we used aerobic laboratory incubations (n=40) across a temperature gradient ((15, 20, 25, 30) oC) at constant soil moisture (60% water holding capacity) for 120 days and measured CO2 respired. Cumulative CO2 respired increased with increasing incubation temperature. Cumulative CO2 respired also increased with elevation as upper elevations support greater amounts of C. However, when normalized by SOC, we found that the temperature response of CO2 respiration was greater in soils derived from lower than higher elevations (p<0.05). These results indicate that the response of SOC decomposition to elevated temperatures differs strongly across the landscape in semi-arid ecosystems.

  17. Land Surface Temperature Measurements from EOD MODIS Data

    NASA Technical Reports Server (NTRS)

    Wan, Zheng-Ming

    1998-01-01

    We made more tests of the version 2.0 daily Level 2 and Level 3 Land-Surface Temperature (LST) code (PGE 16) jointly with the MODIS Science Data Support Team (SDST). After making minor changes a few times, the PGE16 code has been successfully integrated and tested by MODIS SDST, and recently has passed the inspection at the Goddard Distributed Active Archive Center (DAAC). We conducted a field campaign in the area of Mono Lake, California on March 10, 1998, in order to validate the MODIS LST algorithm in cold and dry conditions. Two MODIS Airborne Simulator (MAS) flights were completed during the field campaign, one before noon, and another around 10 pm PST. The weather condition for the daytime flight was perfect: clear sky, the column water vapor measured by radiosonde around 0.3 cm, and wind speed less than a half meter per second. The quality of MAS data is good for both day and night flights. We analyzed the noise equivalent temperature difference (NE(delta)T) and the calibration accuracy of the seven MAS thermal infrared (TIR) bands, that are used in the MODIS day/night LST algorithm, with daytime MAS data over four flat homogeneous study areas: two on Grant Lake (covered with ice and snow, respectively), one on Mono Lake, and another on the snow field site where we made field measurements. NE(delta)T ranges from 0.2 to 0.6 k for bands 42, 45, 46, and 48. It ranges from 0.8 to 1.1 K for bands 30-32. The day and night MAS data have been used to retrieve surface temperature and emissivities in these bands. A simple method to correct the effect of night thin cirrus has been incorporated into the day/night LST algorithm in dry atmospheric conditions. We compared the retrieved surface temperatures with those measured with TIR spectrometer, radiometers and thermistors in the snow test site, and the retrieved emissivity images with topographic map. The daytime LST values match well within 1 K. The night LST retrieved from MAS data is 3.3 K colder than those from

  18. Different responses of the skin temperature to physical exercise: Systematic review.

    PubMed

    Neves, Eduardo B; Vilaca-Alves, Jose; Antunes, Natacha; Felisberto, Ivo M V; Rosa, Claudio; Reis, Victor M

    2015-08-01

    Studies suggest that skin temperature behavior varies according to the type of exercise, intensity, duration, muscle mass and subcutaneous fat layer. In this sense, the aim of this study was to investigate the skin temperature behavior in the active muscles and other body segments, during and after exercise, according to the type and intensity of the exercise. A systematic literature review was conducted between November 2014 and March 2015 in the Web of Science database, using the terms "thermography" and "exercise" and "muscle" to achieve the objective of this study. During the research were found 55 scientific articles which were subjected to a selection process. Inclusion criteria were: Studies in human beings and original research. The exclusion criterion was the presence of subjects with some kind of disease. The seven papers that make up the present review are dated between 2008 and 2015. From all analyzed studies, it was possible to understand the general behavior of the active muscle skin temperature during the exercise, immediately after and in the 48h after exercise, according to the type and intensity of the exercise performed, which are illustrated in two figures. It can be concluded that the skin temperature over active muscles increases during high intensity anaerobic exercise, decreases slowly after exercise and increases again in the days after the exercise. On the other hand, during low intensity aerobic exercise, skin temperature over active muscles decreases, returning to normal values a few minutes after it and present a small rise in the following days. With regard to the skin temperature over non-active muscles, it can be seen that it decreases during exercise, returning to normal values a few minutes after it and rise similarly to the skin temperature over active muscles in the following days, in all types of exercises studied.

  19. Thermopreference, tolerance and metabolic rate of early stages juvenile Octopus maya acclimated to different temperatures.

    PubMed

    Noyola, Javier; Caamal-Monsreal, Claudia; Díaz, Fernando; Re, Denisse; Sánchez, Adolfo; Rosas, Carlos

    2013-01-01

    Thermopreference, tolerance and oxygen consumption rates of early juveniles Octopus maya (O. maya; weight range 0.38-0.78g) were determined after acclimating the octopuses to temperatures (18, 22, 26, and 30°C) for 20 days. The results indicated a direct relationship between preferred temperature (PT) and acclimated temperature, the PT was 23.4°C. Critical Thermal Maxima, (CTMax; 31.8±1.2, 32.7±0.9, 34.8±1.4 and 36.5±1.0) and Critical Thermal Minima, (CTMin; 11.6±0.2, 12.8±0.6, 13.7±1.0, 19.00±0.9) increased significantly (P<0.05) with increasing acclimation temperatures. The endpoint for CTMax was ink release and for CTMin was tentacles curled, respectively. A thermal tolerance polygon over the range of 18-30°C resulted in a calculated area of 210.0°C(2). The oxygen consumption rate increased significantly α=0.05 with increasing acclimation temperatures between 18 and 30°C. Maximum and minimum temperature quotients (Q10) were observed between 26-30°C and 22-26°C as 3.03 and 1.71, respectively. These results suggest that O. maya has an increased capability for adapting to moderate temperatures, and suggest increased culture potential in subtropical regions southeast of México.

  20. Abundance trend with condensation temperature for stars with different Galactic birth places

    NASA Astrophysics Data System (ADS)

    Adibekyan, V.; Delgado-Mena, E.; Figueira, P.; Sousa, S. G.; Santos, N. C.; González Hernández, J. I.; Minchev, I.; Faria, J. P.; Israelian, G.; Harutyunyan, G.; Suárez-Andrés, L.; Hakobyan, A. A.

    2016-08-01

    Context. During the past decade, several studies reported a correlation between chemical abundances of stars and condensation temperature (also known as Tc trend). However, the real astrophysical nature of this correlation is still debated. Aims: The main goal of this work is to explore the possible dependence of the Tc trend on stellar Galactocentric distances, Rmean. Methods: We used high-quality spectra of about 40 stars observed with the HARPS and UVES spectrographs to derive precise stellar parameters, chemical abundances, and stellar ages. A differential line-by-line analysis was applied to achieve the highest possible precision in the chemical abundances. Results: We confirm previous results that [X/Fe] abundance ratios depend on stellar age and that for a given age, some elements also show a dependence on Rmean. When using the whole sample of stars, we observe a weak hint that the Tc trend depends on Rmean. The observed dependence is very complex and disappears when only stars with similar ages are considered. Conclusions: To conclude on the possible dependence of the Tc trend on the formation place of stars, a larger sample of stars with very similar atmospheric parameters and stellar ages observed at different Galactocentric distances is needed. Based on observations collected with the HARPS spectrograph at the 3.6-m telescope (program ID: 095.D-0717(A)), installed at the La Silla Observatory, ESO (Chile), with the UVES spectrograph at the 8-m Very Large Telescope (program ID: 095.D-0717(B)), installed at the Cerro Paranal Observatory, ESO (Chile). Also based on data obtained from the ESO Science Archive Facility under request numbers: vadibekyan180760, vadibekyan180762, vadibekyan180764, vadibekyan180768, vadibekyan180769, vadibekyan180771, vadibekyan180773, vadibekyan180778, and vadibekyan180779.Tables with stellar parameters and chemical abundances are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or

  1. [Parasitism capacity of Trichogramma pratissolii Querino & Zucchi (Hymenoptera: Trichogrammatidae) on alternative hosts, under different temperatures].

    PubMed

    Zago, Hugo B; Pratissoli, Dirceu; Barros, Reginaldo; Gondim, Manoel G C; Santos, Hugo J G Dos

    2007-01-01

    The successful use of Trichogramma as biocontrol agent depends on its mass production in laboratory, a fundamental step for any biological control program among other factors. This work investigated the parasitism capacity of Trichogramma pratissolii Querino & Zuchi (Hymenoptera: Trichogrammatidae), a new recorded Trichogramma species, parasitizing eggs of Anagasta kuehniella (Zeller) and Corcyra cephalonica (Stainton) (Lepidoptera: Pyralidae) under the temperatures of 15, 18, 21, 24, 27, 30 and 33 degree Celsius. Eggs of these hosts were offered to newly emerged females during 24h. This procedure was repeated daily for each female and each temperature up to female death, in order to estimate daily and accumulated parasitism, and female longevity. On both hosts, the daily parasitism decreased as function of the female age. Under all temperatures studied and both hosts the highest rate of parasitism was observed during the first 24h of host exposure, and reached 80% of total parasitism in the 4th and 3rd days when parasitizing A. kuehniella and C. cephalonica, respectively. On both hosts, the highest parasitism rate was observed under temperatures from 21 degree Celsius to 27 degree Celsius. Average longevities of T. pratissolii females deprived of food emerging from A. kuehniella and C. cephalonica lived for 1.0 and 8.9 days when reared at 15 degree Celsius e 33 degree Celsius, respectively. The results indicate that eggs of A. kuehniella and C. cephalonica and temperatures from 21 degree Celsius to 27 degree Celsius were appropriate to rear T. pratissolii.

  2. Fracture toughness and fracture behavior of SA508-III steel at different temperatures

    NASA Astrophysics Data System (ADS)

    Liu, Jia-hua; Wang, Lei; Liu, Yang; Song, Xiu; Luo, Jiong; Yuan, Dan

    2014-12-01

    The fracture toughness of SA508-III steel was studied in the temperature range from room temperature to 320°C using the J-integral method. The fracture behavior of the steel was also investigated. It was found that the conditional fracture toughness ( J Q) of the steel first decreased and then increased with increasing test temperature. The maximum and minimum values of J Q were 517.4 kJ/m2 at 25°C and 304.5 kJ/m2 at 180°C, respectively. Dynamic strain aging (DSA) was also observed to occur when the temperature exceeded 260°C with a certain strain rate. Both the dislocation density and the number of small dislocation cells effectively increased because of the occurrence of DSA; as a consequence, crack propagation was more strongly inhibited in the steel. Simultaneously, an increasing number of fine carbides precipitated under high stress at temperatures greater than 260°C. Thus, the deformation resistance of the steel was improved and the J Q was enhanced.

  3. HA/Bioglass composite films deposited by pulsed laser with different substrate temperature

    NASA Astrophysics Data System (ADS)

    Wang, D. G.; Chen, C. Z.; Jin, Q. P.; Li, H. C.; Pan, Y. K.

    2014-03-01

    In this experiment, the HA/Bioglass composite films on Ti-6Al-4V were deposited by a pulsed laser at Ar atmosphere, and the influence of substrate temperature on the morphology, phase constitutions, bonding configurations and adhesive strength of the films was studied. The obtained films were characterized by an electron probe microanalyzer (EPMA), scanning electron microscope (SEM), X-ray diffractometer (XRD), Fourier transform infrared spectrometer (FTIR), scratch apparatus, and so on. The results show that the amount of the droplets, the crystallinity, and the critical load of the deposited films all increase with the increase of the substrate temperature; however, the substrate temperature has little influence on the functional groups of the films.

  4. HA/Bioglass composite films deposited by pulsed laser with different substrate temperature

    NASA Astrophysics Data System (ADS)

    Wang, D. G.; Chen, C. Z.; Jin, Q. P.; Li, H. C.; Pan, Y. K.

    2013-05-01

    In this experiment, the HA/Bioglass composite films on Ti-6Al-4V were deposited by a pulsed laser at Ar atmosphere, and the influence of substrate temperature on the morphology, phase constitutions, bonding configurations and adhesive strength of the films was studied. The obtained films were characterized by an electron probe microanalyzer (EPMA), scanning electron microscope (SEM), X-ray diffractometer (XRD), Fourier transform infrared spectrometer (FTIR), scratch apparatus, and so on. The results show that the amount of the droplets, the crystallinity, and the critical load of the deposited films all increase with the increase of the substrate temperature; however, the substrate temperature has little influence on the functional groups of the films.

  5. [Study on the vacuum ultraviolet transmittance of barium fluoride crystals at different temperature].

    PubMed

    Peng, Ru-Yi; Fu, Li-Ping; Tao, Ye

    2014-03-01

    Two VUV-grade BaF2 windows with 0.5 mm-thick and 1 mm-thick respectively were selected to study the transmittance variety with the temperature. The results show that the cutoff wavelength of BaF2 crystals will shift towards the long wave with the increase in temperature. In a certain temperature range, BaF2 crystals can depress 130.4 nm radiation well, and also has a high transmittance at 135.6 nm. Compared with the reported method in which SrF2 crystals can be applied to suppress 130.4 nm stray light by heating, BaF2 crystal can inhibit the 130. 4 nm emission line completely, and thus reduce the power consumption of the device at the same time. This indicates that BaF2 crystals can play an important role in the ionosphere optical remote sensing detection.

  6. Dielectric response of capacitor structures based on PZT annealed at different temperatures

    NASA Astrophysics Data System (ADS)

    Kamenshchikov, Mikhail V.; Solnyshkin, Alexander V.; Pronin, Igor P.

    2016-12-01

    Dielectric response of thin-film capacitor structures of Pt/PZT/Pt deposited by the RF magnetron sputtering method and annealed at temperatures of 540-570 °C was investigated. It was found that dielectric properties of these structures depend on the synthesis temperature. Stability of a polarized state is considered on the basis of the analysis of hysteresis loops and capacitance-voltage (C-V) characteristics. The contribution of the domain mechanism in the dielectric response of the capacitor structure comprising a ferroelectric is discussed. Extreme dependences of electrophysical characteristics of PZT films on their synthesis temperature were observed. Correlation of dielectric properties with microstructure of these films is found out.

  7. Cold-start emissions of modern passenger cars at different low ambient temperatures and their evolution over vehicle legislation categories

    NASA Astrophysics Data System (ADS)

    Weilenmann, Martin; Favez, Jean-Yves; Alvarez, Robert

    The emissions of modern gasoline and diesel passenger cars are reduced by catalysts except in cold-starting. Since catalysts require a certain temperature (typically above 300 °C) to work to full efficiency, emissions are significantly higher during the warm-up phase of the car. The duration of this period and the emissions produced depend on the ambient temperature as well as on the initial temperature of the car's propulsion systems. The additional emissions during a warm-up phase, known as "cold-start extra emissions" (CSEEs) for emission inventory modelling, are mostly assessed by emission measurements at an ambient temperature of 23 °C. However, in many European countries average ambient temperatures are below 23 °C. This necessitates emission measurements at lower temperatures in order to model and assess cold-start emissions for real-world temperature conditions. This paper investigates the influence of regulated pollutants and CO 2 emissions of recent gasoline and diesel car models (Euro-4 legislation) at different ambient temperatures, 23, -7 and -20 °C. We present a survey and model of the evolution of cold-start emissions as a function of different car generations (pre-Euro-1 to Euro-4 legislations). In addition the contribution of CSEEs to total fleet running emissions is shown to highlight their increasing importance. For gasoline cars, it turns out that in average real-world driving the majority of the CO (carbon monoxide) and HC (hydrocarbon) total emissions are due to cold-start extra emissions. Moreover, the cold-start emissions increase considerably at lower ambient temperatures. In contrast, cold-start emissions of diesel cars are significantly lower than those of gasoline cars. Furthermore, the transition from Euro-3 to Euro-4 gasoline vehicles shows a trend for a smaller decline for cold-start extra emissions than for legislative limits. Particle and NO x emission of cold-starts are less significant.

  8. The effect of temperature on apoptosis and adipogenesis on skeletal muscle satellite cells derived from different muscle types

    PubMed Central

    Harding, Rachel L; Clark, Daniel L; Halevy, Orna; Coy, Cynthia S; Yahav, Shlomo; Velleman, Sandra G

    2015-01-01

    Satellite cells are multipotential stem cells that mediate postnatal muscle growth and respond differently to temperature based upon aerobic versus anaerobic fiber-type origin. The objective of this study was to determine how temperatures below and above the control, 38°C, affect the fate of satellite cells isolated from the anaerobic pectoralis major (p. major) or mixed fiber biceps femoris (b. femoris). At all sampling times, p. major and b. femoris cells accumulated less lipid when incubated at low temperatures and more lipid at elevated temperatures compared to the control. Satellite cells isolated from the p. major were more sensitive to temperature as they accumulated more lipid at elevated temperatures compared to b. femoris cells. Expression of adipogenic genes, CCAAT/enhancer-binding protein β (C/EBPβ) and proliferator-activated receptor gamma (PPARγ) were different within satellite cells isolated from the p. major or b. femoris. At 72 h of proliferation, C/EBPβ expression increased with increasing temperature in both cell types, while PPARγ expression decreased with increasing temperature in p. major satellite cells. At 48 h of differentiation, both C/EBPβ and PPARγ expression increased in the p. major and decreased in the b. femoris, with increasing temperature. Flow cytometry measured apoptotic markers for early apoptosis (Annexin-V-PE) or late apoptosis (7-AAD), showing less than 1% of apoptotic satellite cells throughout all experimental conditions, therefore, apoptosis was considered biologically not significant. The results support that anaerobic p. major satellite cells are more predisposed to adipogenic conversion than aerobic b. femoris cells when thermally challenged. PMID:26341996

  9. The effect of temperature on apoptosis and adipogenesis on skeletal muscle satellite cells derived from different muscle types.

    PubMed

    Harding, Rachel L; Clark, Daniel L; Halevy, Orna; Coy, Cynthia S; Yahav, Shlomo; Velleman, Sandra G

    2015-09-01

    Satellite cells are multipotential stem cells that mediate postnatal muscle growth and respond differently to temperature based upon aerobic versus anaerobic fiber-type origin. The objective of this study was to determine how temperatures below and above the control, 38°C, affect the fate of satellite cells isolated from the anaerobic pectoralis major (p. major) or mixed fiber biceps femoris (b. femoris). At all sampling times, p. major and b. femoris cells accumulated less lipid when incubated at low temperatures and more lipid at elevated temperatures compared to the control. Satellite cells isolated from the p. major were more sensitive to temperature as they accumulated more lipid at elevated temperatures compared to b. femoris cells. Expression of adipogenic genes, CCAAT/enhancer-binding protein β (C/EBPβ) and proliferator-activated receptor gamma (PPARγ) were different within satellite cells isolated from the p. major or b. femoris. At 72 h of proliferation, C/EBPβ expression increased with increasing temperature in both cell types, while PPARγ expression decreased with increasing temperature in p. major satellite cells. At 48 h of differentiation, both C/EBPβ and PPARγ expression increased in the p. major and decreased in the b. femoris, with increasing temperature. Flow cytometry measured apoptotic markers for early apoptosis (Annexin-V-PE) or late apoptosis (7-AAD), showing less than 1% of apoptotic satellite cells throughout all experimental conditions, therefore, apoptosis was considered biologically not significant. The results support that anaerobic p. major satellite cells are more predisposed to adipogenic conversion than aerobic b. femoris cells when thermally challenged.

  10. Differential Listeria monocytogenes strain survival and growth in Katiki, a traditional Greek soft cheese, at different storage temperatures.

    PubMed

    Kagkli, Dafni-Maria; Iliopoulos, Vassilios; Stergiou, Virginia; Lazaridou, Anna; Nychas, George-John

    2009-06-01

    Katiki Domokou is a traditional Greek cheese, which has received the Protected Designation of Origin recognition since 1994. Its microfloras have not been studied although its structure and composition may enable (or even favor) the survival and growth of several pathogens, including Listeria monocytogenes. The persistence of L. monocytogenes during storage at different temperatures has been the subject of many studies since temperature abuse of food products is often encountered. In the present study, five strains of L. monocytogenes were aseptically inoculated individually and as a cocktail in Katiki Domokou cheese, which was then stored at 5, 10, 15, and 20 degrees C. Pulsed-field gel electrophoresis was used to monitor strain evolution or persistence during storage at different temperatures in the case of the cocktail inoculum. The results suggested that strain survival of L. monocytogenes was temperature dependent since different strains predominated at different temperatures. Such information is of great importance in risk assessment studies, which typically consider only the presence or absence of the pathogen.

  11. Micromachined room-temperature microbolometers for millimeter-wave detection

    NASA Astrophysics Data System (ADS)

    Rahman, Arifur; de Lange, Gert; Hu, Qing

    1996-04-01

    We have combined silicon micromachining technology with planar circuits to fabricate room-temperature niobium microbolometers for millimeter-wave detection. In this type of detector, a thin niobium film, with a dimension much smaller than the wavelength and fabricated on a 1 μm thick Si3N4 membrane, acts both as a radiation absorber and temperature sensor. Incident radiation is coupled into the microbolometer by a 0.37λ dipole antenna of center frequency 95 GHz with a 3 dB bandwidth of 15%, which is impedance matched with the Nb film. An electrical noise equivalent power (NEP) of 4.5×10-10 W/√Hz has been achieved. This is comparable to the best commercial room-temperature millimeter-wave detectors.

  12. Thermoelectric Performance for SnSe Hot-Pressed at Different Temperature

    NASA Astrophysics Data System (ADS)

    Li, D.; Li, J. C.; Qin, X. Y.; Zhang, J.; Song, C. J.; Wang, L.; Xin, H. X.

    2017-01-01

    Herein, nanoparticles SnSe are prepared by fusion method together with ball-milling technique and the effect of hot-pressing temperatures on the thermoelectric properties of the dense materials is explored. Due to the optimization of carrier concentration, the peak figure of merit (ZT) value of the compacted material reaches 0.73 for SnSe sample hot-pressed at 400°C and 450°C. The present investigation indicates that the thermoelectric performance of the SnSe compound can be significantly improved by sintering with suitable temperature.

  13. XMM-Newton and Chandra cross-calibration using HIFLUGCS galaxy clusters . Systematic temperature differences and cosmological impact

    NASA Astrophysics Data System (ADS)

    Schellenberger, G.; Reiprich, T. H.; Lovisari, L.; Nevalainen, J.; David, L.

    2015-03-01

    Context. Robust X-ray temperature measurements of the intracluster medium (ICM) of galaxy clusters require an accurate energy-dependent effective area calibration. Since the hot gas X-ray emission of galaxy clusters does not vary on relevant timescales, they are excellent cross-calibration targets. Moreover, cosmological constraints from clusters rely on accurate gravitational mass estimates, which in X-rays strongly depend on cluster gas temperature measurements. Therefore, systematic calibration differences may result in biased, instrument-dependent cosmological constraints. This is of special interest in light of the tension between the Planck results of the primary temperature anisotropies of the cosmic microwave background (CMB) and Sunyaev-Zel'dovich-plus-X-ray cluster-count analyses. Aims: We quantify in detail the systematics and uncertainties of the cross-calibration of the effective area between five X-ray instruments, EPIC-MOS1/MOS2/PN onboard XMM-Newton and ACIS-I/S onboard Chandra, and the influence on temperature measurements. Furthermore, we assess the impact of the cross-calibration uncertainties on cosmology. Methods: Using the HIFLUGCS sample, consisting of the 64 X-ray brightest galaxy clusters, we constrain the ICM temperatures through spectral fitting in the same, mostly isothermal regions and compare the different instruments. We use the stacked residual ratio method to evaluate the cross-calibration uncertainties between the instruments as a function of energy. Our work is an extension to a previous one using X-ray clusters by the International Astronomical Consortium for High Energy Calibration (IACHEC) and is carried out in the context of IACHEC. Results: Performing spectral fitting in the full energy band, (0.7-7) keV, as is typical of the analysis of cluster spectra, we find that best-fit temperatures determined with XMM-Newton/EPIC are significantly lower than Chandra/ACIS temperatures. This confirms the previous IACHEC results obtained

  14. The relationship between heart rate and rate of oxygen consumption in Galapagos marine iguanas (Amblyrhynchus cristatus) at two different temperatures.

    PubMed

    Butler, Patrick J; Frappell, Peter B; Wang, Tobias; Wikelski, Martin

    2002-07-01

    To enable the use of heart rate (fH) for estimating field metabolic rate (FMR) in free-ranging Galapagos marine iguanas Amblyrhynchus cristatus, we determined the relationships between fH and mass-specific rate of oxygen consumption (sVO2) in seven iguanas before and during exercise on a treadmill and during the post-exercise period. The experiments were conducted at 27 and 35 degrees C, which are the temperatures that represent the lowest and highest average body temperatures of these animals in the field during summer. There were linear and significant relationships between fH and sVO2 at both temperatures (r(2)=0.86 and 0.91 at 27 degrees C and 36 degrees C, respectively). The slopes of the two regression lines did not differ, but there were significant differences in their intercepts. Thus, while heart rate can be used to predict FMR, the effects of temperature on the intercept of the regression must be taken into account when converting fH to sVO2. On the basis of our data, this can be achieved by applying the following formula: sVO2=0.0113fH-0.2983Q(10)((T(b)-27)/10). The increase in sVO2 with elevated body temperature results from an increase in fH, with no significant change in mass-specific oxygen pulse (sO(2) pulse; cardiac stroke volume times the difference in oxygen content between arterial and mixed venous blood). However, during exercise at both temperatures, increases in fH are insufficient to provide all of the additional O(2) required and there are also significant increases in the sO(2) pulses. This creates the situation whereby the same fH at the two temperatures can represent different values of sVO2.

  15. Handling Temperature Bursts Reaching 464°C: Different Microbial Strategies in the Sisters Peak Hydrothermal Chimney

    PubMed Central

    Kurtz, Stefan; LaRoche, Julie

    2014-01-01

    The active venting Sisters Peak (SP) chimney on the Mid-Atlantic Ridge holds the current temperature record for the hottest ever measured hydrothermal fluids (400°C, accompanied by sudden temperature bursts reaching 464°C). Given the unprecedented temperature regime, we investigated the biome of this chimney with a focus on special microbial adaptations for thermal tolerance. The SP metagenome reveals considerable differences in the taxonomic composition from those of other hydrothermal vent and subsurface samples; these could be better explained by temperature than by other available abiotic parameters. The most common species to which SP genes were assigned were thermophilic Aciduliprofundum sp. strain MAR08-339 (11.8%), Hippea maritima (3.8%), Caldisericum exile (1.5%), and Caminibacter mediatlanticus (1.4%) as well as to the mesophilic Niastella koreensis (2.8%). A statistical analysis of associations between taxonomic and functional gene assignments revealed specific overrepresented functional categories: for Aciduliprofundum, protein biosynthesis, nucleotide metabolism, and energy metabolism genes; for Hippea and Caminibacter, cell motility and/or DNA replication and repair system genes; and for Niastella, cell wall and membrane biogenesis genes. Cultured representatives of these organisms inhabit different thermal niches; i.e., Aciduliprofundum has an optimal growth temperature of 70°C, Hippea and Caminibacter have optimal growth temperatures around 55°C, and Niastella grows between 10 and 37°C. Therefore, we posit that the different enrichment profiles of functional categories reflect distinct microbial strategies to deal with the different impacts of the local sudden temperature bursts in disparate regions of the chimney. PMID:24837379

  16. Simultaneous measurement of temperature and force with high sensitivities based on filling different index liquids into photonic crystal fiber.

    PubMed

    Liang, Hu; Zhang, Weigang; Geng, Pengcheng; Liu, Yange; Wang, Zhi; Guo, Junqi; Gao, Shecheng; Yan, Suyuan

    2013-04-01

    A double-filled photonic crystal fiber (PCF) was fabricated by filling liquids of different indexes into two air holes in the cladding. The core mode coupled to the local cladding modes LP(01) and LP(11) in the 1310 and 1550 nm wavebands, respectively. Due to the unique characteristics of the mode coupling, the resonant peaks in different resonance areas shifted to the opposite directions with the variations of the temperature or the force. The double-filled PCFs achieved in this work showed useful applications in the simultaneous measurement of both the temperature and the force.

  17. CHANGES IN THE RAT EEG SPECTRA AND CORE TEMPERATURE AFTER EXPOSURE TO DIFFERENT DOSES OF CHLORPYRIFOS.

    EPA Science Inventory

    Our previous study showed that single exposure to 25 mg/kg (p.o.) of organophsphate pesticide chlorpyrifos (CHP) led to significant alterations in all EEG frequency bands within 0.1-50 Hz range, reduction in core temperature (Tc) and motor activity (MA). The alterations in EEG pe...

  18. Association of weekly suicide rates with temperature anomalies in two different climate types.

    PubMed

    Dixon, P Grady; Sinyor, Mark; Schaffer, Ayal; Levitt, Anthony; Haney, Christa R; Ellis, Kelsey N; Sheridan, Scott C

    2014-11-13

    Annual suicide deaths outnumber the total deaths from homicide and war combined. Suicide is a complex behavioral endpoint, and a simple cause-and-effect model seems highly unlikely, but relationships with weather could yield important insight into the biopsychosocial mechanisms involved in suicide deaths. This study has been designed to test for a relationship between air temperature and suicide frequency that is consistent enough to offer some predictive abilities. Weekly suicide death totals and anomalies from Toronto, Ontario, Canada (1986-2009) and Jackson, Mississippi, USA (1980-2006) are analyzed for relationships by using temperature anomaly data and a distributed lag nonlinear model. For both analysis methods, anomalously cool weeks show low probabilities of experiencing high-end suicide totals while warmer weeks are more likely to experience high-end suicide totals. This result is consistent for Toronto and Jackson. Weekly suicide totals demonstrate a sufficient association with temperature anomalies to allow some prediction of weeks with or without increased suicide frequency. While this finding alone is unlikely to have immediate clinical implications, these results are an important step toward clarifying the biopsychosocial mechanisms of suicidal behavior through a more nuanced understanding of the relationship between temperature and suicide.

  19. SEASONAL DIFFERENCES IN CLEAR-SKY NIGHTTIME FORAGE TEMPERATURE IN PROXIMITY TO DECIDUOUS TREES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Considerable research has been done on daytime forage shading by silvopasture trees since solar radiation is required for photosynthesis. However, trees also impact nighttime temperature on clear nights when trees also effectively shade forages from cold skies. Appalachia has a temperate climate a...

  20. Characteristics and nutrient values of biochars produced from giant reed at different temperatures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Application of biochars to soils is suggested as an effective way for improving soil quality. To investigate the effect of pyrolysis temperature on properties and nutrients value, biochars were produced from giant reed [Arundo donax L.] at 300-600 degrees Celsius and characterized for their physical...

  1. Determination of volatile aroma compounds in beef using differences in steak thickness and cook surface temperature.

    PubMed

    Kerth, Chris

    2016-07-01

    Top loin steaks with a United States Department of Agriculture (USDA) grade of Select were cut 1.3cm, 2.5cm, or 3.8cm thick and cooked on a skillet at 177°C, 204°C, or 232°C. Aroma compounds described as fatty, tallow, and oily are highly related to the identity of beef flavor. These compounds are produced in the highest quantity when steaks are cooked either at low temperatures (177°C) or for short periods of time. Whereas, aroma compounds described as roasted, nutty, or fruity are developed from browning the surface of the steak as a result of cooking at high skillet surface temperatures (232°C) or for long periods of time, as would be seen cooking thick steaks (3.8cm). This study shows that the amount of specific aroma compounds can be predicted (r(2) values up to 0.62) from measured cooking times and temperatures. It may be possible to develop beef steak flavor by recommending steak thickness and cooking temperatures.

  2. Small differences in temperature interact with solar radiation to alter anthocyanin in grapes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Despite a century of research, we still lack a concrete, mechanistic understanding of solar radiation and temperature effects on anthocyanin accumulation and composition, crucial for red wine grapes. Our aim was to elucidate the mechanistic response to microclimate of anthocyanin metabolism in Viti...

  3. Association of Weekly Suicide Rates with Temperature Anomalies in Two Different Climate Types

    PubMed Central

    Dixon, P. Grady; Sinyor, Mark; Schaffer, Ayal; Levitt, Anthony; Haney, Christa R.; Ellis, Kelsey N.; Sheridan, Scott C.

    2014-01-01

    Annual suicide deaths outnumber the total deaths from homicide and war combined. Suicide is a complex behavioral endpoint, and a simple cause-and-effect model seems highly unlikely, but relationships with weather could yield important insight into the biopsychosocial mechanisms involved in suicide deaths. This study has been designed to test for a relationship between air temperature and suicide frequency that is consistent enough to offer some predictive abilities. Weekly suicide death totals and anomalies from Toronto, Ontario, Canada (1986–2009) and Jackson, Mississippi, USA (1980–2006) are analyzed for relationships by using temperature anomaly data and a distributed lag nonlinear model. For both analysis methods, anomalously cool weeks show low probabilities of experiencing high-end suicide totals while warmer weeks are more likely to experience high-end suicide totals. This result is consistent for Toronto and Jackson. Weekly suicide totals demonstrate a sufficient association with temperature anomalies to allow some prediction of weeks with or without increased suicide frequency. While this finding alone is unlikely to have immediate clinical implications, these results are an important step toward clarifying the biopsychosocial mechanisms of suicidal behavior through a more nuanced understanding of the relationship between temperature and suicide. PMID:25402561

  4. No enhancement of cyanobacterial bloom biomass decomposition by sediment microbial fuel cell (SMFC) at different temperatures.

    PubMed

    Ye, Tian-Ran; Song, Na; Chen, Mo; Yan, Zai-Sheng; Jiang, He-Long

    2016-11-01

    The sediment microbial fuel cell (SMFC) has potential application to control the degradation of decayed cyanobacterial bloom biomass (CBB) in sediment in eutrophic lakes. In this study, temperatures from 4 to 35 °C were investigated herein as the major impact on SMFC performance in CBB-amended sediment. Under low temperature conditions, the SMFC could still operate, and produced a maximum power density of 4.09 mW m(-2) at 4 °C. Coupled with the high substrate utilization, high output voltage was generated in SMFCs at high temperatures. The application of SMFC affected the anaerobic fermentation progress and was detrimental to the growth of methanogens. At the same time, organic matter of sediments in SMFC became more humified. As a result, the fermentation of CBB was not accelerated with the SMFC application, and the removal efficiency of the total organic matter was inhibited by 5% compared to the control. Thus, SMFC could operate well year round in sediments with a temperature ranging from 4 to 35 °C, and also exhibit practical value by inhibiting quick CBB decomposition in sediments in summer against the pollution of algae organic matter.

  5. Growth of Salmonella and Listeria monocytogenes on fresh-cut cantaloupe under different temperature abuse scenarios

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Effective cold chain management is a critical component of food safety practice. In this study, we examined the impact of commonly encountered temperature abuse scenarios on the proliferation of Salmonela enterica and Listeria monocytogenes on fresh-cut cantaloupe. During one week of storage, Salmon...

  6. Clearance of yellow pigments lutein and zeathanxin in channel catfish reared at different water temperatures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A study was conducted to determine clearance time of yellow pigments lutein and zeaxanthin in channel catfish at various temperatures. Fish of initial weight of 13.4 g were stocked into flow-through aquaria and fed once daily with a yellow pigment enhanced diet for 11 weeks when the yellow color be...

  7. Compressive behavior of bulk metallic glass under different conditions --- Coupled effect of temperature and strain rate

    NASA Astrophysics Data System (ADS)

    Yin, Weihua

    Metallic glass was first reported in 1960 by rapid quenching of Au-Si alloys. But, due to the size limitation, this material did not attract remarkable interest until the development of bulk metallic glasses (BMGs) with specimen sizes in excess of 1 mm. BMGs are considered to be promising engineering materials because of their ultrahigh strength, high elastic limit and wear resistance. However, they usually suer from a strong tendency for localized plastic deformation with catastrophic failure. Many basic questions, such as the origin of shear softening and the strain rate eect remain unclear. In this thesis, the mechanical behavior of the Zr55Al 10Ni5Cu30 bulk metallic glass and a metallic glass composite is investigated. The stress-strain relationship for Zr55Al10Ni 5Cu30 over a wide range of strain rate (5x10 --5 to 2x103 s--1) was investigated in uniaxial compression loading using both MTS servo-hydraulic system (quasi-static) and compression Kolsky bar system (dynamic). The effect of the strain rate on the fracture stress at room temperature was discussed. Based on the experimental results, the strain rate sensitivity of the bulk metallic glass changes from a positive value to a negative value at high strain rate, which is a consequence of the significant adiabatic temperature rise during the dynamic testing. In order to characterize the temperature eect on the mechanical behavior of the metallic glass, a synchronically assembled heating unit was designed to be attached onto the Kolsky bar system to perform high temperature and high strain rate mechanical testing. A transition from inhomogeneous deformation to homogeneous deformation has been observed during the quasi-static compressive experiments at testing temperatures close to the glass transition temperature. However, no transition has been observed at high strain rates at all the testing temperatures. A free volume based model is applied to analyze the stress-strain behavior of the homogeneous

  8. Evaluation of Nocturnal Temperature Forecasts Provided by the Weather Research and Forecast Model for Different Stability Regimes and Terrain Characteristics

    NASA Astrophysics Data System (ADS)

    Battisti, Adriano; Acevedo, Otávio C.; Costa, Felipe D.; Puhales, Franciano S.; Anabor, Vagner; Degrazia, Gervásio A.

    2017-03-01

    The quality of nocturnal temperature forecasts made by the Weather Research and Forecast (WRF) numerical model is evaluated. The model was run for all July 2012 nights, and temperature fields compared to hourly observations made at 26 weather stations in southern Brazil. Four different planetary boundary-layer (PBL) schemes are considered: Bougeault-Lacarrere (BouLac), Quasi-Normal Scale Elimination (QNSE), Yonsei University (YSU) and Mellor-Yamada-Janjic (MYJ). Additional simulations to assess the role of higher horizontal and vertical resolutions were performed using the MYJ scheme. All schemes, except BouLac, underestimated the 2-m temperature, and in all cases the temperature bias is dependent on wind speed. At high wind speeds, all schemes exhibit a cold bias, which is greater for those that yield lower nocturnal surface-layer turbulent intensity. The elevation difference between each station and the model nearest grid point H_{it{station}} -H_{it{gridpoint}} is highly correlated with the temperature simulation error. We found that a consistent cold bias is restricted to conditions with low-level clouds. We concluded that one possible means of improving nocturnal temperature forecast is to use parametrization schemes that allow for higher turbulent intensity in near-neutral conditions. The results indicate that this improvement would partially counteract the misrepresentation of the low-level cloud cover. In most stable cases, a post-processing algorithm based on terrain characteristics may improve the forecasts.

  9. Evaluation of Nocturnal Temperature Forecasts Provided by the Weather Research and Forecast Model for Different Stability Regimes and Terrain Characteristics

    NASA Astrophysics Data System (ADS)

    Battisti, Adriano; Acevedo, Otávio C.; Costa, Felipe D.; Puhales, Franciano S.; Anabor, Vagner; Degrazia, Gervásio A.

    2016-10-01

    The quality of nocturnal temperature forecasts made by the Weather Research and Forecast (WRF) numerical model is evaluated. The model was run for all July 2012 nights, and temperature fields compared to hourly observations made at 26 weather stations in southern Brazil. Four different planetary boundary-layer (PBL) schemes are considered: Bougeault-Lacarrere (BouLac), Quasi-Normal Scale Elimination (QNSE), Yonsei University (YSU) and Mellor-Yamada-Janjic (MYJ). Additional simulations to assess the role of higher horizontal and vertical resolutions were performed using the MYJ scheme. All schemes, except BouLac, underestimated the 2-m temperature, and in all cases the temperature bias is dependent on wind speed. At high wind speeds, all schemes exhibit a cold bias, which is greater for those that yield lower nocturnal surface-layer turbulent intensity. The elevation difference between each station and the model nearest grid point H_{station} -H_{gridpoint} is highly correlated with the temperature simulation error. We found that a consistent cold bias is restricted to conditions with low-level clouds. We concluded that one possible means of improving nocturnal temperature forecast is to use parametrization schemes that allow for higher turbulent intensity in near-neutral conditions. The results indicate that this improvement would partially counteract the misrepresentation of the low-level cloud cover. In most stable cases, a post-processing algorithm based on terrain characteristics may improve the forecasts.

  10. Stress effect of different temperatures and air exposure during transport on physiological profiles in the American lobster Homarus americanus.

    PubMed

    Lorenzon, S; Giulianini, P G; Martinis, M; Ferrero, E A

    2007-05-01

    Homarus americanus is an important commercial species that can survive 2-3 days out of water if kept cool and humid. Once caught for commercial purpose and shipped around the world, a lobster is likely to be subjected to a number of stressors, including emersion and air exposure, hypoxia, temperature changes and handling. This study focused on the effect of transport stress and specifically at different animal body temperature (6 and 15 degrees C) and air exposure during commercial transport and recovery process in water. Animals were monitored, by hemolymph bleeding, at different times: 0 h (arrival time at plant) 3 h, 12 h, 24 h and 96 h after immersion in the stocking tank with a water temperature of 6.5+/-1.5 degrees C. We analysed the effects by testing some physiological variables of the hemolymph: glucose, cHH, lactate, total protein, cholesterol, triglycerides, chloride and calcium concentration, pH and density. All these variables appeared to be influenced negatively by high temperature both in average of alteration from the physiological value and in recovering time. Blood glucose, lactate, total protein, cholesterol were significantly higher in the group with high body temperature compared to those with low temperature until 96 h after immersion in the recovery tank.

  11. Interactive effects of temperature and UVB radiation on methane emissions from different organs of pea plants grown in hydroponic system.

    PubMed

    Abdulmajeed, Awatif M; Derby, Samantha R; Strickland, Samantha K; Qaderi, Mirwais M

    2017-01-01

    There is no information on variation of methane (CH4) emissions from plant organs exposed to multiple environmental factors. We investigated the interactive effects of temperature and ultraviolet-B (UVB) radiation on CH4 emissions from different organs of pea (Pisum sativum L. var. UT234 Lincoln). Plants were grown hydroponically under two temperatures (22/18°C and 28/24°C; 16h day/8h night) and two levels of UVB radiation [0 and 5kJm(-2) d(-1)] in controlled-environment growth chambers for ten days, after two weeks of initial growth under ambient temperatures. Methane emission, dry mass, growth index, electrical conductivity (EC), pectin, total chlorophyll content, gas exchange and flavonoids were measured in the appropriate plant organs - leaf, stem and root. Higher temperatures increased CH4 emissions, leaf mass ratio, and shoot: root mass ratio. Neither temperature nor UVB had significant effects on leaf, stem, root and total dry mass, EC, pectin, total chlorophyll, as well as specific leaf mass. Among plant organs, there were differences in CH4, EC, pectin and total chlorophyll. Methane and EC were highest for the stem and lowest for the leaf; leaf had highest, but stem had lowest, pectin content; total chlorophyll was highest in the leaf but lowest in the root. Higher temperatures decreased leaf flavonoids, net carbon dioxide assimilation, and water use efficiency. Overall, environmental stressors increased aerobic CH4 emission rates, which varied with plant organs.

  12. Development and survival of embryos of lake herring at different constant oxygen concentrations and temperatures

    USGS Publications Warehouse

    Brooke, L.T.; Colby, P.J.

    1980-01-01

    Eggs of lake herring (Coregonus artedii) were incubated in a continuous-flow system at four constant water temperatures (2-8°C) and five dissolved oxygen (DO) concentrations (1-12 mg/L). In comparison with incubation time at 12 mg/L DO, time to median hatch was significantly longer (P<0.05) at 2 mg/L at 6°C (no hatch at 1 mg/L), at 3 mg/L or less at 4°C, and at 4 mg/L or less at 2°C. The time between hatching of the first and last eggs varied inversely with temperature. Mean total lengths of newly hatched fry were significantly shortened (P < 0.05) at 1 and 2 mg/L DO. At 6 and 8°C, percent survival through hatching was greater than at 2 and 4°C at DO of 4 mg/L or more, but fell to zero at 1 mg/L. The percentage of normal fry produced decreased noticeably below 4 mg/L DO. The optimum temperature for highest percentage survival of normal fry decreased directly with the level of dissolved oxygen. The temperatures at which the highest percentages of normal fry hatched from eggs incubated at DO concentrations of 4 or 8, 2, and 1 mg/L, were 6, 4, and 2°C, respectively-indicating a decreasing DO demand by embryos incubated at the lower temperatures. Our findings supported a previously published hypothesis that DO concentrations below 4 mg/L can be adverse to survival and development of coregonid embryos in nature.

  13. High Strain Rate Compression of Martensitic NiTi Shape Memory Alloy at Different Temperatures

    NASA Astrophysics Data System (ADS)

    Qiu, Ying; Young, Marcus L.; Nie, Xu

    2017-02-01

    The compressive response of martensitic NiTi shape memory alloy (SMA) rods has been investigated using a modified Kolsky compression bar at various strain rates (400, 800, and 1200 s-1) and temperatures [room temperature and 373 K (100 °C)], i.e., in the martensitic state and in the austenitic state. SEM, DSC, and XRD were performed on NiTi SMA rod samples after high strain rate compression in order to reveal the influence of strain rate and temperature on the microstructural evolution, phase transformation, and crystal structure. It is found that at room temperature, the critical stress increases slightly as strain rate increases, whereas the strain-hardening rate decreases. However, the critical stress under high strain rate compression at 373 K (100 °C) increase first and then decrease due to competing strain hardening and thermal softening effects. After high rate compression, the microstructure of both martensitic and austenitic NiTi SMAs changes as a function of increasing strain rate, while the phase transformation after deformation is independent of the strain rate at room temperature and 373 K (100 °C). The preferred crystal plane of the martensitic NiTi SMA changes from ( 1bar{1}1 )M before compression to (111)M after compression, while the preferred plane remains the same for austenitic NiTi SMA before and after compression. Additionally, dynamic recovery and recrystallization are also observed to occur after deformation of the austenitic NiTi SMA at 373 K (100 °C). The findings presented here extend the basic understanding of the deformation behavior of NiTi SMAs and its relation to microstructure, phase transformation, and crystal structure, especially at high strain rates.

  14. 2D nano-Y2O3:Eu3+ photoluminescence with different preparation methods and annealing temperatures

    NASA Astrophysics Data System (ADS)

    Zhou, Jun; Zhu, Yanhua; Liu, Huangqing; Chai, Yifeng; Yang, Yibo; Zhang, Qingjun; Wang, Lingling

    2017-03-01

    Y2O3:Eu3+ (YOE) material is an important photoluminescence (PL) material. In this paper, YOE nano-powder was prepared by the low-temperature combustion method (LTC) and sol-gel method (SG), and annealed with different temperatures, respectively. The influence of the preparation methods and annealing temperature on the optical properties of YOE were well studied. The as-synthesized nano-YOE samples were characterized by x-ray diffraction (XRD), PL spectra, and Fourier transform infrared spectroscopy (FTIR). Results show that with the increase in annealing temperature, the charge transfer band (CTB) of samples blue-shifts and shows higher intensity. FTIR results indicate that low emission intensity decreases luminescence intensity and deteriorates the optical properties of nano-YOE. We also studied the spectral intensity changes before and after laser-induced, which shows the intensity of significant changes over time.

  15. Temperature sensitivity of extracellular enzyme kinetics in subtropical wetland soils under different nutrient and water level conditions

    NASA Astrophysics Data System (ADS)

    Goswami, S.; Inglett, K.; Inglett, P.

    2012-12-01

    Microbial extracellular enzymes play an important role in the initial steps of soil organic matter decomposition and are involved in regulating nutrient cycle processes. Moreover, with the recent concern of climate change, microbial extracellular enzymes may affect the functioning (C losses, C sequestration, greenhouse gas emissions, vegetation changes) of different ecosystems. Hence, it is imperative to understand the biogeochemical processes that may be climate change sensitive. Here, we have measured the Michaelis Menten Kinetics [maximal rate of velocity (Vmax) and half-saturation constant (Km)] of 6 enzymes involved in soil organic matter decomposition (phosphatase, phosphodiesterase, β-D-glucosidase, cellobiohydrolase, leucine aminopeptidase, N-Acetyl-β-D glucosaminidase) in different nutrient(P) concentration both aerobically and anaerobically in Everglade water conservation area 2A (F1, F4-slough and U3-slough). Temperature sensitivity of different enzymes is assessed within soil of different P concentrations. We hypothesized that the temperature sensitivity of the enzyme changes with the biogeochemical conditions including water level and nutrient condition. Furthermore, we have tested specific hypothesis that higher P concentration will initiate more C demand for microbes leading to higher Vmax value for carbon processing enzymes in high P site. We found temperature sensitivity of all enzymes for Vmax and Km under both aerobic and anaerobic condition ranges from 0.6 to 3.2 for Vmax and 0.5 to 2.5 for Km. Q10 values of Km for glucosidase indicate more temperature sensitivity under anaerobic condition. Under aerobic condition higher temperature showed significant effect on Vmax for bisphosphatase between high P and low P site. Decreasing P concentration from F1 site to U3-S site had showed significant effect in all temperature on carbon processing enzyme. This suggests that in high P site, microbes will use more carbon-processing enzyme to get more carbon

  16. Effect of temperature difference between manikin and wet fabric skin surfaces on clothing evaporative resistance: how much error is there?

    PubMed

    Wang, Faming; Kuklane, Kalev; Gao, Chuansi; Holmér, Ingvar

    2012-01-01

    Clothing evaporative resistance is one of the inherent factors that impede heat exchange by sweating evaporation. It is widely used as a basic input in physiological heat strain models. Previous studies showed a large variability in clothing evaporative resistance both at intra-laboratory and inter-laboratory testing. The errors in evaporative resistance may cause severe problems in the determination of heat stress level of the wearers. In this paper, the effect of temperature difference between the manikin nude surface and wet textile skin surface on clothing evaporative resistance was investigated by both theoretical analysis and thermal manikin measurements. It was found that the temperature difference between the skin surface and the manikin nude surface could lead to an error of up to 35.9% in evaporative resistance of the boundary air layer. Similarly, this temperature difference could also introduce an error of up to 23.7% in the real clothing total evaporative resistance (R ( et_real ) < 0.1287 kPa m(2)/W). Finally, it is evident that one major error in the calculation of evaporative resistance comes from the use of the manikin surface temperature instead of the wet textile fabric skin temperature.

  17. Effect of temperature difference between manikin and wet fabric skin surfaces on clothing evaporative resistance: how much error is there?

    NASA Astrophysics Data System (ADS)

    Wang, Faming; Kuklane, Kalev; Gao, Chuansi; Holmér, Ingvar

    2012-01-01

    Clothing evaporative resistance is one of the inherent factors that impede heat exchange by sweating evaporation. It is widely used as a basic input in physiological heat strain models. Previous studies showed a large variability in clothing evaporative resistance both at intra-laboratory and inter-laboratory testing. The errors in evaporative resistance may cause severe problems in the determination of heat stress level of the wearers. In this paper, the effect of temperature difference between the manikin nude surface and wet textile skin surface on clothing evaporative resistance was investigated by both theoretical analysis and thermal manikin measurements. It was found that the temperature difference between the skin surface and the manikin nude surface could lead to an error of up to 35.9% in evaporative resistance of the boundary air layer. Similarly, this tempe