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NOAA generates a suite of Ocean Heat Content (OHC) products for the North Atlantic and the North and South Pacific basins on a daily basis. Knowledge of the upper Ocean Heat Content is a critical aid in assessing the ocean's impact on Tropical Cyclones (TCs) and weather events. In-situ and satellite measurements of Sea Surface Temperature (SST) and Sea Surface Height Anomaly (SSHA) are used to generate the OHC product suite. The evaluated suite includes the 20°C (D20) and 26°C (D26) isotherm depths, the mixed layer depth (MLD) and mapping errors. Two cases are presented within the context of situational awareness showing the underling oceanic variability during the lifecycles of TC's Irma and Dorian. [ABSTRACT FROM AUTHOR]

Background/objectives: We sought to describe the experience among members of the Hemangioma Investigator Group with pulsed dye laser (PDL) in the treatment of nonulcerated infantile hemangioma (IH) in pediatric patients in the pre‐ and post‐beta‐blocker era. Methods: A multicenter retrospective cohort study was conducted in patients with nonulcerated IH treated with laser therapy. Patient demographics, IH characteristics, indications for/timing of laser therapy, as well as laser parameters were collected. Responses to laser therapy were evaluated using a visual analog scale (VAS). Results: One hundred and seventeen patients with IH were treated with PDL. 18/117 (15.4%) had early intervention (defined as <12 months of life), and 99/117 (84.6%) had late intervention (≥12 months of life). In the late intervention group, 73.7% (73/99) had additional medical management of their IH. The mean age at PDL initiation for the late intervention group was 46.7 ± 35.3 months of life (range 12–172 months) with total number of treatments to maximal clearing of 4.2 ± 2.8 (range 1–17). Those who received propranolol prior to PDL received fewer sessions (1.1 fewer sessions, approaching significance [p =.056]). On the VAS, there was a mean 85% overall improvement compared to baseline (range 18%–100%), with most improvement noted in erythema and/or telangiectasias. The incidence of adverse effects was 6/99 (6.1%). Conclusions: PDL is a useful tool in the treatment of IH, with notable improvement of telangiectasia and erythema and low risk of complications. PDL is often introduced after the maximal proliferative phase. [ABSTRACT FROM AUTHOR]

The prime motive of this study is to assess the behavior of curvaturedependent channel boundaries on the Magnetohydrodynamic (MHD) peristaltic flow of viscous liquid with heat transportation effects via a curved channel. The analysis is reported by considering the Hall currents, Joule, and viscous dissipations effects. Further, no-slip momentum and thermal conditions are incorporated. Mathematical model is subjected to the implication of large wavelength and weaker magnetic Reynolds number schemes. Galilean transformation is used to convert the problem from laboratory frame into wave frame. The solution of the system of equations is executed by employing the numerical method ND solve (built-in command in Mathematica). The volume and mean flow rates are computed and examined. Graphical illustrations are provided to evaluate the nature of distinct constraints on velocity, temperature, and rate of heat transportation. Results show that the curvature constraint has significant impact on the mechanical and thermal features of the flow. The damping effects of the magnetic field improve the temperature and rate of heat transportation at the boundary. Moreover, a reduction in thermal transportation rate is noticed for the increased curvature constraint values. [ABSTRACT FROM AUTHOR]

We describe here partial outcomes of a study in which we seek to unveil the historical-sociocultural influences that permeated the technical-scientific work of James Prescott Joule and show his contributions to the physics teachers training. We tried to answer the following question: What were the theoretical, social and cultural elements that influenced Joule's work? In this sense, we present a brief history of the development of science in the period of the Industrial Revolution, as well as the industrial development of Greater Manchester, in which Salford is part of its metropolitan region, city where Joule was born and grew up. Next we show the importance and the cultural influence of the social and academic environment of Joule and of theoretical elements that influenced, mainly, the works on Joule effect and the mechanical equivalent of the heat. From the study carried out, we organized some notes aimed at contributing to the teachers’ training.

The principle of conservation of energy tells us that 'energy can neither be created nor destroyed but only transformed'. The validity of the principle is without question. The problem is the concept. Contemporary physicists have asserted that we do not know what energy is. We find, however, 19th century physicists, contemporary physicists and historians of science who converge on the point: Mayer and Joule discovered energy. Therefore, we do not know what energy is, but we know these authors discovered it. What did they then discover? What can we learn from this with regard to the energy concept problem? To deal with this issue, I will distinguish between what the authors did experimentally and what they said about the phenomena. This method of analysis makes the difference in relation to historical works on the subject. In a second step, I will consider the introduction of the energy concept, which is from 1850s, and the reification of the energy in 1880s. Finally, I will address the energy conservation principle and the concept of energy conveyed by this principle in contemporary textbooks. As we shall see, the conservation of a magnitude that we call energy nowadays was discovered by Mayer and Joule; an indestructible and transformable entity was not. Adopting the original conservation principle would be enough to avoid the energy concept problem. [ABSTRACT FROM AUTHOR]

History of science provides access to a reservoir of meaningful experiments that can be studied and reproduced in classrooms. This is the case of Joule's paddle-wheel experiment which displays the potentiality to help students improve their understanding of the concept of energy. This experiment has been mentioned in many physics textbooks during the twentieth century. Recently, it has received renewed attention by several researchers in science education. However, the accounts of Joule's experiment proposed by these researchers are at variance with each other: either in terms of equivalences, in terms of energy change, or in terms of energy transformation and Rankine's definition. This raises several questions: What is their respective contribution to the understanding of the historical emergence of the energy concept, and to the understanding of the very meaning of this concept? Are these accounts concurrent? Eventually, how can they help for the teaching energy? To investigate these questions, historical details concerning this experiment are first considered. It is stressed that Joule did not made use of the concept of energy, and instead described his experiment in terms of conversion of living force into heat. The three accounts of Joule's experiment are then presented and their respective contribution discussed. By emphasizing different aspects of this experiment, they are shown to suggest different strategies for teaching energy. For all that, they are not contradictory and, considered together, they bring to light the great potential of Joule's experiment to foster students understanding of this concept. [ABSTRACT FROM AUTHOR]

In recent decades, the development of sciences and technologies had a significant impact in society. This impact has been object of analysis from several standpoints, i.e., scientific, communication, historical and anthropological. Consequently, serious changes were required by the society. One of these has been the emerging relationship science in society and its foundations of applied sciences. A related foundational challenging is the educational process, which was and still is an unlimited challenge for teachers and professors: i.e., levels of understanding, curricula, activing critical engagement, transfer knowledge—and—skills, management, classroom and subsequently pre-service teachers need special teacher education. Taking into account Joule's bicentenary commemoration in physics and Nature of Science teaching (NoS) this paper introduces to a level of inquiring within historical and NoS approaches in the pre-service teachers, typically science, technology, engineering and mathematics. In particular, history and historiography of Joule's physics (e.g., his arguments on electric–magnetic engine, mechanical equivalent of heat and free expansion) are dealt with. [ABSTRACT FROM AUTHOR]

Joule's Energy Conservation Law was the first "meta-law": a general principle that all physical equations must satisfy. It has led to many important and useful physical discoveries. However, a recent analysis seems to indicate that this meta-law is inconsistent with other principles—such as the existence of free will. We show that this conclusion about inconsistency is based on a seemingly reasonable—but simplified—analysis of the situation. We also show that a more detailed mathematical and physical analysis of the situation reveals that not only Joule's principle remains true—it is actually strengthened: it is no longer a principle that all physical theories should satisfy—it is a principle that all physical theories do satisfy. [ABSTRACT FROM AUTHOR]

The current investigation aims to examine heat transfer as well as entropy generation analysis of Powell-Eyring nanofluid moving over a linearly expandable non-uniform medium. The nanofluid is investigated in terms of heat transport properties subjected to a convectively heated slippery surface. The effect of a magnetic field, porous medium, radiative flux, nanoparticle shapes, viscous dissipative flow, heat source, and Joule heating are also included in this analysis. The modeled equations regarding flow phenomenon are presented in the form of partial-differential equations (PDEs). Keller-box technique is utilized to detect the numerical solutions of modeled equations transformed into ordinary-differential equations (ODEs) via suitable similarity conversions. Two different nanofluids, Copper-methanol (Cu-MeOH) as well as Graphene oxide-methanol (GO-MeOH) have been taken for our study. Substantial results in terms of sundry variables against heat, frictional force, Nusselt number, and entropy production are elaborate graphically. This work's noteworthy conclusion is that the thermal conductivity in Powell-Eyring phenomena steadily increases in contrast to classical liquid. The system's entropy escalates in the case of volume fraction of nanoparticles, material parameters, and thermal radiation. The shape factor is more significant and it has a very clear effect on entropy rate in the case of GO-MeOH nanofluid than Cu-MeOH nanofluid. [ABSTRACT FROM AUTHOR]

We report on the development of novel intrinsic conducting polymer two terminal surge protection devices. These resettable current limiting devices consist of polyaniline nanofibres doped with methane sulphonic acid electrochemically deposited between two 55 μm spaced gold electrodes. At normal applied voltages, the low resistance devices act as passive circuit elements, not affecting the current flow. However during a current surge the devices switch from ohmic to non-ohmic behaviour, limiting current through the device. After the current surge has passed, the devices reset back to their original state. Our studies show that a partial de-doping/re-doping process caused by the rapid diffusion of moisture out of or into the polymer film during joule heating/cooling is the underlying mechanism responsible. [ABSTRACT FROM AUTHOR]

This paper discusses the special role that the Peltier effect plays in thermoelectric cooling. From a particular energy balance for a thermocouple, we can conclude that the Peltier component pumps out the energy of all other terms: Joule, Fourier, Seebeck, and thermoelectric cooling. We emphasize also that in this energy balance, there is a need to include a new contribution, named after Seebeck that usually is not considered in the literature. We discuss a new method to evaluate the Peltier coefficient using measurements of the two temperature gradients at the junction of a thermocouple. An arrangement has been built to explore this method. A precise value for the Peltier coefficient of a thermocouple has been obtained but which deviates from the Kelvin relation. A better design of the experimental device is needed. [ABSTRACT FROM AUTHOR]

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This paper aimed to carry out an analysis of Joule’s original texts, written in the middle of the XIX century, trying to understand how the changes in heat concept occurred throughout his work. To support the theoretical analysis, a literature review was made with texts about the Science history and the study of alternative conceptions about heat. Guided by this literature review, the Discursive Textual Analysis was used as the methodology to examine which factors influenced Joule in changing his conception of the nature of heat. Joule initially accept the caloric theory and, instigated by internal aspects of his research and work by other researchers such as: Rumford, Davy and Herapath, he begins to understand the heat as a state of motion of the particles. We believe this work has the potential to serve as a subsidy for the teaching of Physics, where the study of Joule’s work can contribute so that there is a reframing of the heat concept for the students.

New thin-film range resistors have been developed at the National Metrology Institute of Japan, to re-establish ac–dc voltage transfer standards in the 100–1000-V range at frequencies of 1–100 kHz. In earlier studies, the voltage dependence of the ac–dc transfer difference was observed during step-up procedures above 300 V. One of the possible reasons for this voltage dependence is the temperature rise due to the Joule heating, which may cause changes in the resistance of the resistor, as well as the temperature dependence of the dielectric losses in the resistor coating. In this paper, to reduce the voltage dependence, new thin-film heaters were directly fabricated on an aluminum nitride substrate to prevent heat from accumulating in the range resistor. The voltage dependence was evaluated by measuring the differences in impedance among various range resistors. Negligible voltage dependence in the step-up procedures from 100 to 1000 V was achieved. [ABSTRACT FROM AUTHOR]

The calibration of transient current sensors is fundamental for the reliability of high currents short-circuit tests. The test can be performed with prospective or withstand current, and in both cases, the dynamic behavior of the current sensors has to be investigated, due to their influence on the scale factor (SF) value. The requirements of the IEC 62475 standard can be achieved with a calibration in transient conditions, performed with an approved reference measuring system. In this paper, a more accurate measuring system is presented, for the improvement of the Istituto Nazionale di Ricerca Metrologica high transient current measuring capability. The result is achieved by analyzing the performance in digitalization of a commercial Keysight (former Agilent) multimeter 3458A, with a custom algorithm that can also perform the calculation of Joule integral ($I^{2}t$) on a given amount of time along the acquired signal. The objective of the research is the realization of a measurement system with an uncertainty compatible with the test laboratory requirements, both for the determination of SF and evaluation of the performance in the measurement of $I^{2}t$ in the device under calibration. [ABSTRACT FROM AUTHOR]

Since 2013, the NIM-2 joule balance apparatus has been designed and constructed at the National Institute of Metrology for the precise measurement of the Planck constant and the redefinition of the kilogram. By the end of 2016, the NIM-2 was ready for measurement in vacuum. Before the deadline of July 1, 2017, the first determination of the Planck constant obtained with the NIM-2 in vacuum was published. The measured Planck constant is 6.626 069 2(16) $\times 10^{-34}$ Js, which differs in relative terms by $-1.27 \times 10^{-7}$ from the Committee on Data of the International Council for Science (CODATA) 2014 value, with a relative standard uncertainty of $2.4 \times 10^{-7}$. However, this result is not used for the CODATA 2017 special adjustment because its uncertainty is bigger than $6 \times 10^{-8}$. The main uncertainty contributions are from the external field, alignment, and mass calibration. At present, the consistent research on the experiments related to the redefinition of the kilogram is still encouraged and expected by the Consultative Committee for Units. Therefore, great efforts are still put forward to improve the NIM-2 joule balance to get an uncertainty of 10−8 level. A series of improvements in progress is presented here. [ABSTRACT FROM AUTHOR]

Alignment is very important for Kibble balances and the joule balance at the measurement uncertainty region of several parts in 108. In the joule balance, if the suspended coil is in a misalignment state, parasitic displacements including the horizontal displacements along the ${x}$ - and ${y}$ -axes and the angular displacements around the ${x}$ -, ${y}$ -, and z-axes, will be produced and introduce alignment errors during the measurement of the joule balance. It is key for the joule balance to measure these parasitic displacements of the suspended coil during the alignment stages. So this paper describes the parasitic displacements measurement method based on our laser interferometer system. By studying and discussing the decoupling methods, we can calculate the five degrees of freedom parasitic displacements without complicating the structures of the suspended coil. In addition, several uncertainty sources have been theoretically analyzed to simplify the adjustment procedure during the parasitic displacements measurement. The experimental results show that the decoupling methods are effective for the parasitic displacements of the suspended coil, and this paper can contribute to a precise alignment in the joule balance. [ABSTRACT FROM AUTHOR]

Photovoltaic (PV) cells have become one of the most promising renewable energy technologies. To make PV cells more competitive with incumbent technologies, higher power output densities are needed. One promising approach is to add bifaciality to existing monofacial PV devices, allowing more output power from the additional reflection of sunlight from the ground (albedo α). For example, bifaciality can be added to Silicon Heterojunction (SHJ) solar cells with Interdigitated Back Contacts (IBCs) by opening up the gaps between the back metal contacts, but the optimum gap (w) that maximizes the power output is unknown. In this paper, we show that the optimum gap [ w = 1 − 1 + α α α + c − 1 2 ] maximizes the IBC-SHJ bifacial power output [ P ∝ (1 + α) (1 − 2 a / c )], where c is the ratio of output power density to power loss due to shadowing and Joule heating, The results are validated by self-consistent finite-element device modeling. For a typical α = 0.3 , an optimized bifacial IBC SHJ cell will produce 17% more power output than state-of-the-art monofacial IBC SHJ cells. The results encourage development of bifacial IBC solar cells as a next generation PV technology. [ABSTRACT FROM AUTHOR]

The existence of two types of magnon populations created in volume and in the surfaces of the CoxPt1−x/Pt multilayer was demonstrated. A band structure of these magnons was evidenced by the shape of the calculated excitation spectra. Two bands of energy allowed for a creation of these magnetic excitations are obtained. "Creation gaps" and associated lifetimes are also calculated. The comparison of the calculated relaxation times with experimental results is more than satisfactory. [ABSTRACT FROM AUTHOR]

Abstract Joule heating can instantaneously achieve high temperatures (>2000 °C) by applying electrical current on a resistive material. This ohmic heating by the passage of an electric current through a conducting domain may effectively heal the defective sites (i.e., vacancies, structural defects, and sp3 oxygen groups) of graphene oxide (GO) and revert them into sp2 domains. Indeed, the direction of electric field controls the texture of GO with preferential alignment, which significantly affects the transport properties along the fiber axis. Here we present electrical current-induced manipulation of resistive domain (i.e. Joule heating) as an effective healing method for the defect sites in GO fibers (GOFs). Systematic control of input current restores the sp2 lattice structures within fibers in a well-controlled manner. Structural evolution mechanism is proposed for multilayer stacked graphitic structures as well as graphene sheet plane under the reduction process. This defect-healing principle is rapid, environmentally benign and energy efficient, compared to other defect restoration methods, and yields tailored-aligned fibers with a high current-carrying capability and facile charge transport, which is potentially beneficial for power cables and other relevant applications. Graphical abstract Current-induced self-annealing on graphene fibers for the healing of defects in graphene fibers. Image 1 [ABSTRACT FROM AUTHOR]

The article presents the research conducted on defects and dislocations in graphene layers for electrical and electronic transport properties of device applications. The article imaged various local defects in chemical vapor deposition graphene within a stipulated time by using lock-in thermography. The differences in electrical resistance caused by the micrometer-scale defects, apparent as nonuniform Joule heating on polycrystalline and epitaxially grown graphene.

The 3D flow of non-Newtonian nanoliquid flows past a bidirectional stretching sheet with heat transfer is investigated in the present study. It is assumed that viscosity of the liquid varies with temperature. Carreau non-Newtonain model, Tiwari and Das nanofluid model are used to formulate the problem. The impacts of Joule heating, nonlinear radiation and non-uniform (space and temperature dependent) heat source/sink are accounted. Al-Cu-CH3OH and Cu-CH3OH are considered as nanoliquids for the present study. The solution of the problem is attained by the application of shooting and R.K. numerical procedures. Graphical and tabular illustrations are incorporated with a view of understanding the influence of various physical parameters on the flow field. We eyed that using of Al-Cu alloy nanoparticles in the carrier liquid leads to superior heat transfer ability instead of using only Aluminum nanoparticles. Weissenberg number and viscosity parameter have inclination to exalt the thermal field. [ABSTRACT FROM AUTHOR]

Abstract Photon engineering can be exploited to control the nonlinear evolution of the drive pulse in a laser–plasma accelerator (LPA), offering new avenues to tailor electron beam phase space on a femtosecond time scale. One promising option is to drive an LPA with an incoherent stack of two sub-Joule, multi-TW pulses of different colors. Slow self-compression of the bi-color optical driver delays electron dephasing, boosting electron beam energy without accumulation of a massive low-energy tail. The modest energy of the stack affords kHz-scale repetition rate at manageable laser average power. Propagating the stack in a pre-formed plasma channel induces periodic self-focusing in the trailing pulse, causing oscillations in the size of accelerating bucket. The resulting periodic injection generates, over a mm-scale distance, a train of GeV-scale electron bunches with 5D brightness exceeding 1 0 17 A ∕ m 2. This unconventional comb-like beam, with femtosecond synchronization and controllable energy spacing of components, emits, via Thomson scattering, a train of highly collimated gigawatt γ -ray pulses. Each pulse, corresponding to a distinct energy band between 2.5 and 25 MeV, contains over 1 0 6 photons. Highlights • Stacked-pulse-driven laser–plasma electron accelerator (SPD LPA) is introduced. • SPD LPA overcomes limitations of conventional single-color LPA energy scaling. • Joule-scale energy of stack permits kHz repetition rate with kW average laser power. • SPD LPA in plasma channel generates a train of bright, fs-scale GeV electron bunches. • Thomson scattering from e-bunch train produces multi-color train of MeV γ -ray pulses. [ABSTRACT FROM AUTHOR]

In the present study, an analysis for steady hydromagnetic mixed convective generalised Couette flow between two infinite parallel plates of arbitrary electrical conductivities and finite thicknesses filled with a porous medium in the presence of a uniform transverse magnetic field in a rotating system with the Hall effect is presented. The heat transfer characteristics of the fluid flows are also investigated, taking viscous and Joule dissipations into account. Exact solutions of the resulting simultaneous ordinary differential equations governing the fluid flows are obtained in a closed form. The closed form analytical solutions for shear stress and mass flow rate are also obtained. To examine the physical consequences and flow characteristics, the numerical results for velocity, induced magnetic field, temperature field, shear stress, mass flow rate, and rate of heat transfer are computed for different values of various system parameters and are displayed in graphical and tabular forms. An interesting observation recorded that there arises flow reversal in the secondary flow direction when the permeability parameter is very small, i.e., when Darcian drag force is very large. [ABSTRACT FROM AUTHOR]

Generating controlled vortices in a sessile surface droplet configuration in an energy efficient manner is an outstanding research problem of interdisciplinary relevance, having implications in widely varying areas ranging from biomedical diagnostics, thermal management to digital microfluidic technology. Here, we experimentally and theoretically demonstrate a simple yet energy efficient strategy for generating controlled vortices inside a surface droplet, by deploying interacting electrical and thermal fields over inter-digitated electrodes on an electrically wetted platform. Unlike the traditional electrically driven mechanisms, this strategy involves significantly low voltage (≤ 10 V) to induce rotational structures inside the droplet, by exploiting the strong spatial gradient of electrical properties on account of the prevailing thermal field as attributable to intrinsically induced Joule heating effects. Our experiments demonstrate that fluid velocities typically of the order of mm/s can be generated inside the droplet within the standard regimes of operating parameters, bearing far-reaching consequences towards enhancing internal mixing in multifarious droplet based microfluidic applications. An inherent integrability with the existing electrowetting on dielectric platforms renders the process ideal to be used in conjunction with digital microfluidic technology. [ABSTRACT FROM AUTHOR]

A theoretical study of mixed convection stagnation point flow towards a stretching surface is presented. The governing boundary layer equations are transformed into a set of highly nonlinear ordinary differential equations using suitable similarity transforms. The semi-analytical solution is obtained using optimal homotopy analysis method (OHAM) and the numerical solution is obtained via finite element method (FEM). Solutions obtained via two different approaches are in excellent agreement, which validates the accuracy of present analysis. In a special case, the present OHAM solution is also validated with the earlier available results. Effect of pertinent flow parameters on the skin friction coefficient and Nusselt number is presented in tabular form, whereas the velocity, temperature and nanoparticle distribution are presented in graphical forms. Further, a quadratic multiple regression analysis on numeric data of skin friction coefficient and Nusselt number is performed. The findings suggest that velocity slip assists the fluid motion in presence of buoyancy forces, whereas it exhibits a retarding nature on fluid motion when no buoyancy forces exist. [ABSTRACT FROM AUTHOR]

We report a novel self-heated CO gas sensor based on Au-functionalized networked SnO 2 -ZnO core-shell nanowires. Increasing the applied voltage particularly enhanced the sensing response due to the self-heating effect within the sensor, and the sensors exhibited good performance without the need for an external heater. The power consumption at 3 and 20 V was estimated to be 11.3 nW and 8.3 μW, respectively. In a sensor with the optimal ZnO shell thickness of 80 nm, the responses for 50 ppm CO were 1.17 and 1.62 at 3 and 20 V, respectively. Also, the important role of ZnO-ZnO homojunctions in the self-heating of the sensor was demonstrated by increasing the ZnO shell thickness, which led to an increase in the sensor response. Furthermore, the optimized sensor exhibited outstanding selectivity toward CO gas. The optimized ZnO shell, the catalytic effect of Au, and the Joule effect contributed to the good, selective response toward CO gas with low power consumption. Since low power consumption is a fundamental requirement for wireless sensors and sensor arrays, this sensor with very low power consumption is a promising choice for such applications. [ABSTRACT FROM AUTHOR]

This paper presents a method to estimate separate components of transmission losses from synchronised phasor measurements in terms of losses in the corresponding elements of the transmission line model. This means separate estimates of Joule losses in series resistive elements and active losses dissipated in the shunt conductive elements, e.g. corona and leakage, and both the consumed and generated reactive power in inductive and capacitive elements of the model are found. The main aim and benefit of the method is a new way to detect corona losses on transmission lines. To facilitate this, the needed mathematical expressions are derived for the estimation of transmission losses from simultaneous, i.e. time-synchronised, phasor measurements based on a distributed parameter multiconductor transmission line model. The efficacy of the derived expressions is analysed in PSCAD simulations and on real data from phasor measurement units (PMU). [ABSTRACT FROM AUTHOR]

In this work we investigate corrections of the quintessence regime of the dark energy on the Joule-Thomson (JT) effect of the Reissner Nordström anti de Sitter (RNAdS) black hole. The quintessence dark energy has equation of state as pq = ωρq in which −1<ω<−13. Our calculations are restricted to ansatz: ω = − 1 (the cosmological constant regime) and ω=−23 (quintessence dark energy). To study the JT expansion of the AdS gas under the constant black hole mass, we calculate inversion temperature Ti of the quintessence RNAdS black hole where its cooling phase is changed to heating phase at a particular (inverse) pressure Pi. Position of the inverse point {Ti, Pi} is determined by crossing the inverse curves with the corresponding Gibbons-Hawking temperature on the T-P plan. We determine position of the inverse point versus different numerical values of the mass M and the charge Q of the quintessence AdS RN black hole. The cooling-heating phase transition (JT effect) is happened for M > Q in which the causal singularity is still covered by the horizon. Our calculations show sensitivity of the inverse point {Ti, Pi} position on the T-P plan to existence of the quintessence dark energy just for large numerical values of the AdS RN black holes charge Q. In other words the quintessence dark energy dose not affect on position of the inverse point when the AdS RN black hole takes on small charges. [ABSTRACT FROM AUTHOR]

In present paper boundary layer flow of Sisko fluid by stretching sheet is examined. Combined effects of nonlinear thermal radiation, heat generation/absorption, Joule heating are discussed. The main purpose is to analyze the entropy generation in Sisko fluid flow. By using suitable similarity variables modeled boundary layer PDE's are transfigured into ODE's. The obtained system of equations are solved by using analytical technique (HAM). Graphs are developed to show the effects of pertinent parameters on velocity, temperature, entropy generation, Bejan number, skin friction and Nusselt number. Velocity for larger material parameter reduces. Temperature is more for greater Biot number and radiation parameter. Bejan number is maximum away from the sheet for shear thickening fluids and approaches to zero for shear thinning fluids. [ABSTRACT FROM AUTHOR]

We present the construction and test results of Coils 2 and 3 of a 3-coil 800-MHz REBCO insert (H800) for the MIT 1.3 GHz LTS/HTS NMR magnet currently under construction. Each of three H800 coils (Coils 1-3) is a stack of no-insulation REBCO double pancakes (DPs). The innermost 8.67-T Coil 1 (26 DPs) was completed in 2016; the middle 5.64-T Coil 2 (32 DPs) has been wound, assembled, and tested; and for the outermost 4.44-T Coil 3, its 38 DPs have been wound and preliminary tests were performed to characterize each DP at 77 K. Included for Coil 2 are: 1) 77-K data of critical current, index, and turn-to-turn characteristic resistivity of eachDP; 2) stacking order of the 32 DPs optimized to maximize the Coil 2 current margin and minimize its Joule dissipation in the pancake-to-pancake joints; 3) procedure to experimentally determine and apply a room-temperature preload to the DP stack; 4) 77- and 4.2-K test results after each of 64 pancakes was over-banded with a 75-μm-thick stainless steel tape for a radial thickness of 5 mm. Presented for each DP in Coil 3 are 77-K dada of critical current, index, and turn-to-turn characteristic resistivity. [ABSTRACT FROM AUTHOR]

Background: No randomized controlled trial before has evaluated the role of low-level laser energy in its analgesic effects in orthodontics. Objective: To evaluate the effect of single application of low-level laser with 4-Joule or 16-Joule energy on pain reduction following elastomeric separators placement. Trial design: A two-arm parallel-group single-blind placebo-controlled randomized controlled trial, with implementation of split-mouth technique in each group. Materials and methods: Twenty-six patients in need of orthodontic treatment with a fixed orthodontic appliance were enrolled and randomly allocated to either the 4-Joule or the 16-Joule laser energy group. Elastomeric separators were applied for the mandibular first molars. For each patient one molar received a single low-level laser dose using an 830-nm Ga-Al-As laser device with either 4-Joule or 16-Joule laser beam energy, while the other molar received a placebo treatment by applying the laser device in the same method and parameters as the counterpart molar without emitting the laser beam. The molar to be irradiated was also randomly chosen using simple randomization technique. Allocation was concealed and patients were blinded to which side would receive the laser irradiation. Main outcome measure was the degree of pain scored during mastication for each mandibular first molar after 1, 6, 12, 24, 48, and 72 hours of both laser and placebo treatments application. A questionnaire with an 100-mm Visual Analogue Scale (VAS) was used for pain assessment. Results: Thirty-six patients were evaluated for eligibility, 10 of them were excluded making the final randomized number 26 patients. One patient dropped out later for not completing the questionnaire. Accordingly, the results of 25 patients were statistically analysed. No statistical significance was found for both low-level laser energy values in comparison to the corresponding placebo treatments. No harms were encountered. Limitations: Intervention provider was not blinded to the intervention. Conclusion: Low-level laser therapy, applied at two different laser energy values, is ineffective in relieving elastomeric separators induced orthodontic pain. [ABSTRACT FROM AUTHOR]