Temperature Analysis of Flaring (AR11283) and non-Flaring (AR12194) Coronal Loops

Here, we study the temperature structure of flaring and non-flaring coronal loops, using extracted loops from images taken in six extreme ultraviolet (EUV) channels recorded by Atmospheric Imaging Assembly (AIA)/ Solar Dynamic Observatory (SDO). We use data for loops of X2.1-class-flaring active region (AR11283) during 22:10UT till 23:00UT, on 2011, September 6; and non-flaring active region (AR12194) during 08:00:00UT till 09:00:00UT on 2014, October 26. By using spatially-synthesized Gaussian DEM forward-fitting method, we calculate the peak temperatures for each strip of the loops. We apply the Lomb-Scargle method to compute the oscillations periods for the temperature series of each strip. The periods of the temperature oscillations for the flaring loops are ranged from 7 min to 28.4 min. These temperature oscillations show very close behavior to the slow-mode oscillation. We observe that the temperature oscillations in the flaring loops are started at least around 10 minutes before the transverse oscillations and continue for a long time duration even after the transverse oscillations are ended. The temperature amplitudes are increased at the flaring time (during 20 min) in the flaring loops. The periods of the temperatures obtained for the non-flaring loops are ranged from 8.5 min to 30 min,but their significances are less (below 0.5) in comparison with the flaring ones (near to one). Hence the detected temperature periods for the non-flaring loops' strips are less probable in comparison with the flaring ones, and maybe they are just fluctuations. Based on our confined observations, it seems that the flaring loops' periods show more diversity and their temperatures have wider ranges of variation than the non-flaring ones. More accurate commentary in this respect requires more extensive statistical research and broader observations.

Night-Restricted Feeding Improves Gut Health by Synchronizing Microbe-Driven Serotonin Rhythm and Eating Activity-Driven Body Temperature Oscillations in Growing Rabbits

The circadian misalignment of the gut microbiota caused by unusual eating times in adult animals is related to disease development. However, whether the composition and diurnal rhythm of gut microbiota can be optimized by synchronizing the window period of eating with natural eating habits to reduce the risk of diarrhea remains unclear, especially in growing animals. In this study, 108 5-week-old weaned rabbits (nocturnal animals) were randomly subjected to daytime feeding (DF) and night-restricted feeding (NRF). At age 12 weeks, six rabbits were selected from each group, and caecum and cecal contents, as well as serum samples were collected at 4-h intervals during 24 h. Overall, NRF was found to reduce the risk of diarrhea in growing rabbits, improved the diurnal rhythm and abundance of beneficial microorganisms, along with the production of beneficial metabolites, whereas reduced the abundance of potential pathogens (Synergistes, Desulfovibrio, and Alistipes). Moreover, NRF improved diurnal rhythm of tryptophan hydroxylase isoform 1 and serotonin. Furthermore, NRF strengthened the diurnal amplitude of body core temperature, and promoted the diurnal expression of intestinal clock genes (BMAL1, CLOCK, REV-ERBα, and PER1), and genes related to the regulation of the intestinal barrier (CLAUDIN-1), and intestinal epithelial cell self-proliferation and renewal (BMI1). In vitro simulation experiments further revealed that synchronization of microbial-driven serotonin rhythm and eating activity-driven body temperature oscillations, which are important zeitgebers, could promote the diurnal expression of clock genes and CLAUDIN-1 in rabbit intestinal epithelial cells (RIEC), and enhance RIEC proliferation. This is the first study to reveal that NRF reprograms the diurnal rhythm of the gut microbiome, promotes the diurnal expression of clock genes and tight junction genes via synchronization of microbial-driven serotonin rhythm and eating activity-driven body temperature oscillations, thereby improving intestinal health and reducing the risk of diarrhea in growing rabbits. Collectively, these results provide a new perspective for the healthy feeding and management of growing animals.

The Effect of Simulated Seasonal Temperatures On Metarhizium Brunneum-Associated Mortality In Two Click Beetle Species, And A Degree-Day Infection Model

Wireworms (Coleoptera: Elateridae), the larvae of adult click beetles are subterranean and generalist crop pests that can be difficult to target. Targeting adult beetles, however, may be an effective method to lower wireworm populations. Metarhizium brunneum (Petch) kills click beetles but the mortality rate was expected to vary according to temperature. Using a thermal gradient plate to simulate daily oscillating temperatures for April, May, and June, the effectiveness of M. brunneum strains LRC112 and F52 in causing mortality to Agriotes obscurus (L.) and A. lineatus (L.) beetles was studied. Mortality was fastest in beetles exposed to June temperatures and slowest in those exposed to April temperatures, with differences among beetle species x M. brunneum strain combinations. Warmer temperatures resulted in more rapid mycelial outgrowth and conidiation in beetle cadavers, with only A. obscurus infected with M. brunneum LRC112 attaining near 100% conidiation. The number of degree days required to kill 50% of the beetles (LDD50) was least for A. obscurus infected with M. brunneum LRC112 (176) followed by A. obscurus x M. brunneum F52 (212), A. lineatus x M. brunneum LRC112 (215), and A. lineatus x M. brunneum F52 (292). Hypothetical calculations showed that M. brunneum exposure earlier in the season resulted in a longer LT50 but the earliest LT50 calendar date. Later M. brunneum exposure dates resulted in lower LT50’s, but later LT50 dates. This conceptual work demonstrates the importance of considering daily temperature oscillations, seasonality, and degree days in predicting the efficacy of entomopathogens to manage agricultural pests.

Temperature oscillations during photoinduced heating of aqueous suspensions of silicon nanoparticles

Temperature oscillations (pulsations) were detected in aqueous suspensions of silicon (Si) nanoparticles NPs under laser irradiation with highly absorbed light. The temperature pulsation frequency was found to depend on the NPs concentration in suspension and laser irradiation power. The observed phenomenon is assumed to be caused by the local overheating of Si NPs close to the boiling point of water, while the average heating of the surrounding liquid was insignificant. The observed phenomenon is discussed in view of potential applications in local photo-induced hyperthermia of cancer.

Experimental Measurements on the Thermal Conductivity of Glycerol-Based Nanofluids with Different Thermal Contrasts

We report, in this work, our study of the thermal conductivity of high-viscosity nanofluids based on glycerol. Three nanofluids have been prepared with different thermal contrasts, by suspending graphene flakes, copper oxides, or silica nanoparticles in pure glycerol. The nanofluids were thermally characterized at room temperature with the 3ω technique, with low amplitudes of the temperature oscillations. A significant enhancement of the thermal conductivity is found in both the glycerol/copper oxide and the glycerol/graphene flake nanofluids. Our results question the role played by the Brownian motion in the microscopic mechanisms of the thermal conductivity of high-viscosity glycerol-based nanofluids. A similar behavior of the thermal conductivity as a function of the nanoparticle volume fraction was found for all three glycerol-based nanofluids presently investigated. These results could be explained on the basis of fractal aggregation in the nanofluids.

Thermal Oscillations in Sea Ice and Soils

<p><b>We present mathematical analysis of temperature oscillations in depth-dependent media by investigating the thermodynamics of sea ice and of soils. Time-series temperature measurements from thermistor strings are common in both sea ice and soils and are used to study their properties, evolution, seepage flux and a host of interactions with their environment. We use numerical tools and perturbation theory to study the propagation of high frequency, small amplitude temperature oscillations through the in-homogeneous media using one dimensional models. Analytical tools for studying such thermal waves are derived.</b></p> <p>In sea ice the absorption of solar radiation and oscillating air temperatures result in two distinct thermal wave propagation behaviours. At depths, stationary waves associated with in place solar heating are observed, whereas near the surface, travelling thermal waves are present due to the quick decay in the absorbed solar radiation and the oscillatory air temperatures. These are observed in thermistor string data taken in McMurdo Sound, Antarctica between 1996-2003. Using a variety of mathematical tools, the leading order behaviour of the diurnal temperature oscillation is approximated in terms of elementary functions and is compared with results from numerical simulations.</p> <p>The thermodynamics of soils differ from sea ice in that all the solar radiation is absorbed at the upper boundary and water movement within the soil carries heat. Macroscale in-homogeneity in the advection-diffusion equation is considered and the thermal wave propagation characteristics are studied using a WKB approximation. The leading order behaviour is shown to reduce exactly to the Stallman equations, being the solution to the thermal wave propagation in a homogeneous soil with constant, uniform water flow. We use the leading order WKB expansion to estimate errors in the homogeneous soil assumption commonly made to estimate the seepage velocity and soil diffusivity. It is shown that the diffusivity estimations are relatively stable and provide reasonably accurate results, but the seepage velocity estimations incur significant errors that should be considered. A frequency dependence in the error leads us to suggest multi-frequency analysis for detection and further studies of the effects of in-homogeneous soil thermodynamics.</p>

Thermal Oscillations in Sea Ice and Soils

<p><b>We present mathematical analysis of temperature oscillations in depth-dependent media by investigating the thermodynamics of sea ice and of soils. Time-series temperature measurements from thermistor strings are common in both sea ice and soils and are used to study their properties, evolution, seepage flux and a host of interactions with their environment. We use numerical tools and perturbation theory to study the propagation of high frequency, small amplitude temperature oscillations through the in-homogeneous media using one dimensional models. Analytical tools for studying such thermal waves are derived.</b></p> <p>In sea ice the absorption of solar radiation and oscillating air temperatures result in two distinct thermal wave propagation behaviours. At depths, stationary waves associated with in place solar heating are observed, whereas near the surface, travelling thermal waves are present due to the quick decay in the absorbed solar radiation and the oscillatory air temperatures. These are observed in thermistor string data taken in McMurdo Sound, Antarctica between 1996-2003. Using a variety of mathematical tools, the leading order behaviour of the diurnal temperature oscillation is approximated in terms of elementary functions and is compared with results from numerical simulations.</p> <p>The thermodynamics of soils differ from sea ice in that all the solar radiation is absorbed at the upper boundary and water movement within the soil carries heat. Macroscale in-homogeneity in the advection-diffusion equation is considered and the thermal wave propagation characteristics are studied using a WKB approximation. The leading order behaviour is shown to reduce exactly to the Stallman equations, being the solution to the thermal wave propagation in a homogeneous soil with constant, uniform water flow. We use the leading order WKB expansion to estimate errors in the homogeneous soil assumption commonly made to estimate the seepage velocity and soil diffusivity. It is shown that the diffusivity estimations are relatively stable and provide reasonably accurate results, but the seepage velocity estimations incur significant errors that should be considered. A frequency dependence in the error leads us to suggest multi-frequency analysis for detection and further studies of the effects of in-homogeneous soil thermodynamics.</p>

High Precision Human Skin Temperature Fluctuations Measuring Instrument

This paper describes the experimental results of testing a prototype of a high precision human skin rapid temperature fluctuations measuring instrument. Based on the author’s work, an original circuit solution on a miniature semiconductor diode sensor has been designed. The proposed circuitry provides operation in the full voltage range with automatic setting and holding the operating point, as well as the necessary slope of the conversion coefficient (up to 2300 mV/°C), which makes it possible to register fast temperature oscillations from the surface of the human body and other biological objects. Simulation results in the Microcap 12 software and laboratory tests have confirmed all declared design specifications: temperature resolution of 0.01 °C, transducer thermal time constant of 0.05 s. An original thermostat and an experimental setup for the simultaneous registration of the electrocardiogram, pulse wave signals from the Biopac polygraph MP36 and a signal of temperature oscillations from the prototype thermometer have been designed for further investigations. The preliminary test results indicates that using the designed measuring instrument gives a possibility to provide an in-depth study of the relationship between micro- and macro-blood circulations manifested in skin temperature fluctuations.

INFLUENCE OF CHANNEL GEOMETRY, PRESSURE, TEMPERATURE, OSCILLATIONS AND ADSORPTION ON OBLITERATION OF SLIT SEALS OF ELECTRIC POWER SYSTEMS

The infl uence of the geometric dimensions and confi guration of slot contactless seals on the obliteration of the gaps of plunger pairs at the design and calculation stage of drive systems of electric power systems units is considered. The combined eff ect of working fl uid contamination and the adsorption eff ect on the overgrowth of the living section of the channel was revealed. The fl ow rate during sample shedding was reduced simultaneously as a result of the channel overgrowing with contamination particles and adsorption, i.e. the formation of boundary fi lms on the channel walls. Leaks through the gap at concentric and eccentric position of the plunger in the sleeve are determined. The minimum gap is found, at which the obliteration process is stabilized and loose mud formations are washed away by the fl ow of the working fl uid. The infl uence of the pressure drop at the ends of the slot gap on the channel obliteration process was revealed. With an increase in the pressure drop, the process of stratifi cation of adsorbed layers of polar molecules accelerates, resulting in an increase in the number of contamination particles trapped in the gap per unit of time. With an increase in the temperature of the working fl uid, the process of channel obliteration accelerates, which is confi rmed by experiments. With an oscillating plunger, the fl ow through the annular gap is less than with a stationary one. This is due to the fact that the oscillating plunger occupies a position in the sleeve close to the concentric one, at which leaks are minimal. A stable fl ow rate is obtained when the working fl uid fl ows through the gaps of the plunger pairs performing reciprocating oscillating movements.