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The procedure with the highest rate of opioid prescription in plastic surgery is abdominoplasty. Additionally, plastic surgery patients are at a particularly elevated risk of becoming opioid-dependent. The main objective of this study was to perform a systematic review and create an algorithm for a multimodal pain regimen specific to patients undergoing abdominoplasty. A systematic search of the research literature was performed to summarize the prevailing understanding of multimodal pain control in the management of abdominoplasty. The initial search yielded 448 articles. Sixty-eight manuscripts were identified for full-text review. The effectiveness of current strategies was evaluated by way of pain scores, opioid usage, and length of stay, as well as other measures of physical function such as time to early mobilization. In 32 studies involving 2451 patients, the efficacy of different pain regimens during abdominoplasty was evaluated. Among nontraditional, opioid-sparing analgesia, efficacy of treatment interventions for improved pain and decreased opioid usage was found inall studies. Among local infusion studies, efficacy of treatment interventions for improved pain and decreased opioid usage was found in 78% of studies. Last, among regional block studies, efficacy of treatment interventions for improved pain was found in 87%, with 73% efficacy for decreased opioid usage. Multimodal pain regimens in abdominoplasty have the potential to play an important role in opioid-sparing practices in medicine by incorporating nonopioid pain adjuvants such as nonsteroidal anti-inflammatory drugs and transversus abdominis plane blocks in the preoperative, perioperative, and postoperative periods. Level of Evidence: 2 [ABSTRACT FROM AUTHOR]

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Magnetic null points are an important aspect of the magnetic field structure of the solar corona and can be sites of enhanced dissipation. This paper uses analytical and numerical models to investigate the plasma structure around a heated null. It is shown that the temperature profile not only differs significantly from that in a uniform field, but also that the profile depends significantly on the spatial structure of the heating. Field lines close to the separatrices and the null point have higher temperatures than a uniform field for the same heating input. The dependence of the results near the null on both the ratio of perpendicular to parallel conduction, and numerical resolution is also explored. The comparison between analytic and numerical solutions also provides a useful benchmark to compare MHD codes with anisotropic thermal conduction. [ABSTRACT FROM AUTHOR]

The primary heat transfer source in the conventional multi-cylinder drying of paper and board is conduction. Conduction is facilitated by high-tension contact with steam-heated cylinders, while convective drying, the main mass transfer source, operates as heated air flows over the article web in the pockets. This conduction process occurs at elevated temperatures and contact pressures to ensure effective contact between the wet paper web and the heated cylinders. The contact pressures and temperatures of the hot surface significantly influence the conductive drying characteristics. This research paper presents an experimental study that involves designing a simple lab-scale setup with in-situ and continuous sensing capabilities for various commercially available grades of paper and board. Embedded thermocouples measure the temperatures of the heated platen and the sheet, allowing the collection of flux data to determine heat transfer characteristics. The goal of this study is to ascertain the instantaneous contact coefficients for different basis weights as a function of moisture content. The acquired data will provide valuable insights and information toward process development, design, and simulation of the article drying process. [ABSTRACT FROM AUTHOR]

In this paper, polyacrylamide (PAM) was used as the main matrix material to form the first layer network structure, and polyvinyl alcohol (PVA) was used as the secondary matrix material to form the second layer network structure. The hydrogels were prepared by free radical in‐situ polymerization and physical cross‐linking. This hydrogel was characterized not only by its semi‐interpenetrating network structure, in which cellulose nanocrystals (CNC) penetrate through the polyacrylamide network but also by the physically and chemically cross‐linked hybrid PAM/PVA double network. The structure and appearance of the hydrogels were characterized by scanning electron microscope and Fourier transform infrared spectrometer, and a series of tests were carried out to detect their mechanical properties, electrical properties and sensing properties. The results show that the hydrogel has good mechanical properties (the elongation at break can reach 600 % and the stress at break can reach 0.16 MPa), and the hydrogel also has good sensing and electrical properties. The addition of organic solvents makes the hydrogels have excellent antifreeze and water retention properties and also have excellent swelling properties. Therefore, the PAM/PVA/CNC dual network interpenetrating composite hydrogel has potential application value in the field of flexible sensors. [ABSTRACT FROM AUTHOR]

Despite the growing literature in high-intensity exercise regarding palm cooling, the acute effects of palm cooling on exercise performance indices, neuromuscular and metabolic responses, have not been described during moderate-intensity resistance exercise. Nine (age, 22 6 1 year; mass, 80.8 6 16.2 kg; height, 1.80 6 0.11 m) healthy, male (n 5 7) and female (n 5 2) resistance-trained subjects performed 4 sets of bench press to failure at 60% 1 repetition maximum with 3-minute passive recovery. Subjects were randomly allocated to either the cooling (COL; 2 minutes of cooling at 10 ˚C) or the control (passive rest; CON) condition separated by 1 week between the conditions. Exercise performance (volume load, repetitions, barbell velocity), muscle activation, blood lactate, and rate of perceived exertion were assessed. Despite changes across the variables during the resistance exercise sessions, there were no statistical differences (p . 0.05) in any of the performance, neuromuscular or physiological responses, between the 2 experimental conditions, despite palm temperature being significantly (p, 0.001) reduced in the cooling condition compared with control throughout. Therefore, based on the results of this study, palm cooling does not enhance acute moderate-intensity resistance exercise. [ABSTRACT FROM AUTHOR]

Heat conduction in the porous media (PM) with gas-liquid-solid three-phase has been numerically investigated. The validation of the adopted numerical method is performed by comparing the effective thermal conductivity (ETC) obtained from the simulation results with the experimental data. The results show that the ETC of the PM increases with increasing solid volume fraction (ϕs) and liquid saturation degree (Sr). Sr has a weaker effect on the ETC compared to ϕs. Similar variation laws of the ETC with Sr and ϕs are found for systems with different solid and liquid thermal conductivity. In this work, the PM is simplified as a circuit network. The modeling for the ETC is performed by defining a weighted harmonic parameter (η) to connect the serial and parallel models. η is closed as a function of Sr, ϕs and the thermal conductivity of the solid and liquid phases. The predictability of the model is evaluated. The results demonstrate that the model can provide accurate estimations for the ETC of the three-phase PM. [ABSTRACT FROM AUTHOR]

The complexity of thermal analysis in practical systems has emerged as a subject of interest in various fields of science and engineering. Extended surfaces, commonly called fins, are crucial cooling and heating mechanisms in many applications, such as refrigerators and power plants. In this study, by using a deterministic approach, we discuss the thermal analysis of conduction, convection, and radiation in the presence of a magnetic force within an extended surface. The present study develops a deep neural network to analyze the mathematical model and to estimate the contributions of each dimensionless model parameter to the thermal dynamics of fins. The deep neural network used in this study makes use of a feedforward architecture in which the weights and biases are updated through backward propagation. The accuracy of the neural network model is validated using results obtained from a spectral-based linearization method. The efficiency rate of the extended surfaces is computed using the neural network and spectral methods. The results obtained demonstrate the accuracy of the neural network-based technique. The findings of this study in relation to the novel mathematical model reveal that utilizing materials with variable thermal conductivity enhances the efficiency rate of the extended surface.

BACKGROUND: Ultrasound Guided Regional Anesthesia (UGRA) has become the standard for regional anesthesia practice, but there is not a standardized educational approach for training residents. The objective of this study was to evaluate the efficacy of an UGRA workshop utilizing the theoretical framework of embodied cognition for anesthesiology residents. METHODS: A workshop was developed consisting of didactics, scanning training on standardized patients (SPs) and anatomy reviews on prosected cadavers that focused on the most common UGRA procedures for the upper and lower extremity. At the beginning of the workshop and at the end of the workshop residents completed pre-test and pre-confidence surveys, as well as post-test and post-confidence surveys, respectively to assess the impact of the workshop. RESULTS: 39 residents (100% of the possible residents) participated in the workshop in 2019. Residents confidence in identifying relevant anatomy for the most common UGRA procedures significantly increased in 13 of the 14 measurements. Residents knowledge gain was also statistically significant from the pre-test to post-test (20.13 ± 3.61 and 26.13 ± 2.34; p

The study of heat transfer in the food industry is as important as in any other industry. Food products are constantly subjected to heat treatments. For this reason, a sunflower food oil, which undergoes heat treatment in the manufacturing process, was chosen for this study. The study was carried out on a laboratory plant and aimed to determine the heat transfer coefficients for three sets of determinations: partial heat transfer coefficient inside - where the warm sunflower oil circulates, partial heat transfer coefficient in the annular space - where cold water circulates and overall heat transfer coefficient, in a tube-in-tube heat exchanger made of copper. The obtained values of heat transfer coefficients were compared with literature data for the same type of food oil. This type of heat exchanger, tube-in-tube, is specific to the food industry. Countercurrent circulation of flows through the appliance was established from the outset, as this type of circulation is preferred from the point of view of determining the performance of heat exchange appliances. Efficiency values were also established for the three sets of experimental determinations. For the calculations, the values for the temperatures of the fluids, both at the inlet and outlet of the apparatus and the values for the volume flow rates of the fluids were required.

The effective and efficient use of biomass briquettes is strongly influenced by the type of stove used and the way it is used. This study aims to design a briquette stove by adding an adjuster: the test fuel used honeycomb briquettes and forest fern charcoal. The heat transfer from burning honeycomb briquettes to a pot of water needs to be maintained so that the heat (temperature) remains constant during the combustion process. In the current use of briquettes, the distance between the briquette flame and the pot of water is unstable because the space is getting further away from the pool of cooking water. The combustion distance is getting farther because the bottom of the initial honeycomb briquettes burns out, causing the surface of the briquettes to decrease and move away from the surface of the water pot. Thus the heat given to the pool of water will reduce. The briquette stove needs to be added with an adjuster to overcome this problem. This adjuster serves to raise the honeycomb briquettes if the surface of the briquettes decreases. With the addition of an adjuster, it will be analyzed how much the heat transfer rate and the stability of the burning distance of the honeycomb briquettes will be. In this study, 2 test models will be used: a stove with an adjuster and a stove without an adjuster, using 14 holes in honeycomb briquettes made from forest ferns using starch (tapioca) adhesive. The distance between the surface of the briquettes and the pot of boiled water is 5 cm. The results showed that the briquette stove using an adjuster could maintain the stability of the combustion distance between the surface of the briquette and the pot of water being cooked with an average temperature t = 567.83 0C and conduction heat transfer q = 5285.699 Watt.

The aging of cable insulation presents a significant threat to the safe operation of cables, with space charge serving as a crucial factor influencing cable insulation degradation. However, the characteristics related to space charge and conduction current behavior during thermal aging remain unclear. This study focused on the thermal aging of cross-linked polyethylene (XLPE) material and utilizes a combined pulse electro-acoustic (PEA) and conduction current testing system to analyze the space charge and conduction current characteristics in the sample under varying electric fields and temperatures. The average charge density, short-circuit residual electric field, electric field distortion rate, and conduction current were studied. The findings indicate that the space charge in the samples following thermal aging is predominantly governed by the injected charge. The amorphous region of XLPE decreases, while the cross-linking degree increases after aging, thereby facilitating charge carrier migration within the sample and reducing the generation of charge carriers through thermal pyrolysis. The minimum temperature required for charge injection is reduced by thermal aging. Furthermore, modifications in conduction current, residual electric field, and average charge density indicate that thermal aging has the potential to alter the microstructure and trap characteristics of XLPE. This study provides empirical evidence to elucidate the underlying mechanism of cable insulation aging. [ABSTRACT FROM AUTHOR]

We explore the crystal structure and ionic conductivity of unfilled and cellulose nanowhisker‐filled polymer electrolytes, based on high molecular weight PEO and LiClO4 at a concentration EO:Li = 6:1 (EO = ether oxygen). At this concentration, the polymer electrolyte forms crystalline PEO6 (PEOy—the crystal structure co‐crystallizes "y" PEO ether oxygens to one Li‐anion pair). While the diffraction patterns for PEO3 and PEO6 with LiClO4 are available, their structures are not. Thus, we optimize these structures using density functional theory and show agreement between simulated and experimental diffraction patterns. The PEO6 crystal shows insufficient Li‐ion conductivity due to a lack of percolated conduction paths, and the crystal structure is unstable following 2 months after annealing. Cellulose nanowhiskers, with their patterned surface OH groups, extend the length of PEO6 tunnels, stabilize these tunnels for as long as a year, and result in the percolation of crystals. Although the EO:Li = 6:1 stoichiometry should not favor PEO3 formation, we observe this crystal phase in some unfilled samples. But, with the addition of nanowhiskers, the patterned surface templates PEO6 formation rather than PEO3. Despite these advantages, nanowhiskers do not improve ionic conductivity as hypothesized. The tools developed in this work allow further mechanistic exploration of conduction through crystalline domains. [ABSTRACT FROM AUTHOR]

We use local stratified shearing-box simulations with magnetic field-aligned thermal conduction to study an idealized model of the coupling between a cold, radiatively efficient accretion disc, and an overlying, hot, two-temperature corona. Evaporation of a cold disc by conduction from the hot corona has been proposed as a means of mediating the soft-to-hard state transitions observed in X-ray binary systems. We model the coronal plasma in our local disc patch as an MHD fluid subject to both free-streaming ion conduction and a parametrized cooling function that captures the collisional transfer of energy from hot ions to colder, rapidly cooling leptons. In all of our models, independent of the initial net vertical magnetic flux (NF) threading the disc, we find no evidence of disc evaporation. The ion heat flux into the disc is radiated away before conduction can heat the disc's surface layers. When an initial NF is present, steady-state temperature, density, and outflow velocities in our model coronae are unaffected by conduction. Instead of facilitating disc evaporation, thermal conduction is more likely to feed the disc with plasma condensing out of the corona, particularly in flows without NF. Our work indicates that uncertainties in the amount of NF threading the disc hold far greater influence over whether or not the disc will evaporate into a radiatively inefficient accretion flow compared to thermal conduction. We speculate that a change in net flux mediates disc truncation/evaporation. [ABSTRACT FROM AUTHOR]

In the present report, the structure–property correlation of 0.9BaZr0.2Ti0.8O3-0.1NiFe2O4 (0.9BZT-0.1NFO) composite is studied. The X-ray Diffraction, Raman spectroscopy and Field Effect Scanning Electron Microscopy (FESEM) reveal the existence of ferroelectric and magnetic phases without any impurity and interdiffusion. The dielectric, ferroelectric and conductivity mechanisms of the sample are studied in a wide range of temperature (RT-500°C) and frequency (100 Hz–1 MHz), respectively. The dielectric constant is larger than 2000 in low frequency (<1 kHz), while it decreases to 500 when the frequency is larger than 4 kHz. Both small polaron and correlated barrier hopping contribute to the conduction mechanism. The multiferroism at room temperature is confirmed by P-E and M-H loop study. The composite obeys the Law of Approach to Saturation at a higher field. The saturation magnetization found from fitting is in good agreement with the experimental value. [ABSTRACT FROM AUTHOR]

Hard coatings like Titanium diboride (TiB2) on silicon substrates which are used for interconnects. micro-electro-mechanical devices and metallurgical protective coatings were analyzed based on shallow depths of nanoindentation penetration. The change in the nature of the contact from Hertzian to Pyramidal both in loading as well as unloading modes were examined. Features like ductile fracture, linear unloading, and the creation of electrical conduction paths were analyzed. These high-precision features are influenced by the thickness and crystalline nature of the films and are significant for device fabrication. [ABSTRACT FROM AUTHOR]

This study aims to optimize the thermodynamic performance of a cold storage distribution box through the integration of a ventilation system. To achieve this goal, a prototype constructed from expanded polystyrene is developed, incorporating an active ventilation system to ensure cold temperature uniformity. Thermocouples are integrated into the device to monitor the temporal temperature evolution with and without ventilation. Concurrently, a 2D thermo-aerodynamic investigation is conducted using computational fluid dynamics (CFD). The numerical modeling of the thermodynamic behavior of the cold source employs polynomial laws as input data for the computational code (UDF functions). A comparison between experimental and numerical results reveals the computational code's accurate prediction of the temporal temperature evolution in the cold storage distribution box, particularly under forced convection conditions. The findings indicate that in the absence of ventilation, thermal exchanges primarily occur through air conduction, whereas with ventilation, exchanges are facilitated by convection. Overall, forced convection induced by the inclusion of a ventilation device enhances thermal transfers and the thermodynamic performance of the cold storage distribution box. Furthermore, air mixing limits thermal stratification, thereby facilitating temperature homogenization. [ABSTRACT FROM AUTHOR]

We present the first implementation of hyperbolic thermal conduction in smoothed particle hydrodynamics. Hyperbolic conduction is a physically motivated alternative to traditional, parabolic conduction. It incorporates a relaxation time, which ensures that heat propagates no faster than a physical signal speed. This allows for larger, Courant-like, time-steps for explicit schemes. Numerical solutions of the hyperbolic conduction equations require added dissipation to remain stable at discontinuities and we present a novel scheme for this. Test cases include a simple step, the Sod Shock Tube, the Sedov–Taylor blast, and a super bubble. We demonstrate how longer relaxation times limit conduction, recovering the purely hydrodynamical results, while short relaxation times converge on the parabolic conduction result. We demonstrate that our scheme is stable with explicit Courant-like time-steps and can be orders of magnitude faster than explicit parabolic conduction, depending on the application. [ABSTRACT FROM AUTHOR]

Recent years have seen an increase in the prevalence of cardiac arrhythmias and conduction disorders in children, which are not always diagnosed in time. In order to verify the nature of arrhythmias in pediatrics as well as in therapy, an accessible and informative method of daily Holter ECG monitoring (DHECGM) is widely used. Aim of the study was to assess the practical value of DHECGM in the algorithm for diagnosing heart rhythm and conduction disorders in pediatric patients. Materials and methods: Analysis of DHECGM was performed in 48 children who were hospitalized in the pediatric department of the Specialized Pediatric Care Center (SPCC) of the Poltava Regional Clinical Hospital (PRCH) in 2022-2023. Research results. Sinus tachyarrhythmia or bradyarrhythmia, wandering atrial pacemaker was detected in half of the patients studied. Supraventricular and/or ventricular extrasystoles were detected in 87.5 % of children. Bi-, tri- and quadrigeminy were observed in 14 (27.1 %) of the patients. First or second degree sinoatrial block was observed in 25 % of patients. Atrioventricular block of 1st or 2nd degree (Mobitz type) with Wenkenbach-Samoilov periods was observed in 8 patients (16.6 %). Combined rhythm and conduction disturbances were observed in 82.3 % of the children studied. The article is illustrated by clinical cases of cardiac rhythm and conduction disorders in children of different ages. Conclusions: DHECGM has broad capabilities for diagnosing cardiac rhythm and conduction abnormalities, allowing early detection of arrhythmias in pediatric patients and providing personalized recommendations. [ABSTRACT FROM AUTHOR]

Abundant, affordable, reliable, and safe energy is the need of nowadays since much heat is wasted due to lack of innovation for converting it into useful purposes. Computational studies are helpful in analyzing physical phenomena releasing heat and saving costs and time that subjected to experimentations. This study is orchestrated to investigate the thermal analysis of heat emitted from the hot mug of tea into open atmosphere through convection, conduction, and radiation phenomena. There were analysed tea mugs made from different materials like glass, plastic, porcelain, and stainless steel. The mathematical models of the thermal energies modes associated with analyzed mugs were explored, coupled and simulated in FEM-based software to obtain productive conclusions. Simulation results showed that change of mesh type impacts on solution of the temperature versus time and space coordinate. Moreover, the influence of different parameters like surface radiosity, total heat flux, mean thermal diffusivity, radiative heat flux, internal total energy flux, and total energy were computed. Finally, the analytical time-varying cooling curves were validated with an experimental study and analytical solutions in good agreement for different mug materials used. On the bases of this study, we suggest that heat released from a warm mug of tea may be very useful if it employed to charge mobile battery through heating pads kept under hot mug of tea. [ABSTRACT FROM AUTHOR]

Background: Interest in cardiac electrophysiology is increasing in sub-Saharan Africa, but the interpretation of results is poorly understood. Cardiac electrophysiology is the study of electrical activity of the heart by virtue of catheters that are positioned in the heart, as opposed to leads placed on the chest surface. It is useful in identifying sites of origin of various cardiac arrhythmias, diagnosing conduction abnormalities and treating various arrhythmias. Material and method: This study is a review of cardiac electrophysiology methods. It aims to help physicians understand and interpret cardiac electrophysiology reports.

Recent years have seen an increase in the prevalence of cardiac arrhythmias and conduction disorders in children, which are not always diagnosed in time. In order to verify the nature of arrhythmias in pediatrics as well as in therapy, an accessible and informative method of daily Holter ECG monitoring (DHECGM) is widely used. Aim of the study was to assess the practical value of DHECGM in the algorithm for diagnosing heart rhythm and conduction disorders in pediatric patients. Materials and Methods: Analysis of DHECGM was performed in 48 children who were hospitalized in the pediatric department of the Specialized Pediatric Care Center (SPCC) of the Poltava Regional Clinical Hospital (PRCH) in 2022-2023. Research results. Sinus tachyarrhythmia or bradyarrhythmia, wandering atrial pacemaker was detected in half of the patients studied. Supraventricular and/or ventricular extrasystoles were detected in 87.5 % of children. Bi-, tri- and quadrigeminy were observed in 14 (27.1 %) of the patients. First or second degree sinoatrial block was observed in 25 % of patients. Atrioventricular block of 1st or 2nd degree (Mobitz type) with Wenkenbach- Samoilov periods was observed in 8 patients (16.6 %). Combined rhythm and conduction disturbances were observed in 82.3 % of the children studied. The article is illustrated by clinical cases of cardiac rhythm and conduction disorders in children of diff erent ages. Conclusions: DHECGM has broad capabilities for diagnosing cardiac rhythm and conduction abnormalities, allowing early detection of arrhythmias in pediatric patients and providing personalized recommendations.

Testing and reliability assessment are crucial aspects when considering the thermal domain's influence on the overall system. Thermal interactions occur between all subsystems, and their separation can disrupt internal thermal interactions, altering temperature profiles. Evaluating functional system reliability requires accounting for the thermal domain's impact on temperature-dependent performance and thermal damage limits. However, testing faces challenges due to the lack of a suitable thermal coupling system capable of transferring thermal interactions by heat conduction between spatially separated subsystems. To address this issue, this paper introduces a thermal coupling system that focuses on the control system and its validation through experimental studies. Two scenarios were investigated: (I) the original assembly situation with direct heat transfer between two subsystems, and (II) a spatially separated scenario utilizing the thermal coupling system to establish heat transfer between the subsystems. The evaluation variables are the temperature curves and the deviations between the two scenarios. Two different tests with a different amount of heat flows are carried out. The thermal coupling system utilizes thermal actuators, specifically Peltier devices, to ensure a zero temperature difference between the original contact points. The control system employs both closed-loop and open-loop control to regulate the heat flow and achieve energy conservation between the spatially separated subsystems. The results demonstrate that the described thermal coupling system yields only slight deviations in temperature curves, indicating its applicability for early evaluation of functional system reliability. This research contributes to a better understanding of thermal interactions in complex systems and provides a valuable tool for enhancing overall system reliability through thermal testing and validation. [ABSTRACT FROM AUTHOR]

Objective Glossopharyngeal nerve block is a useful interventional technique for pain management of the head and neck. It is performed with landmark techniques or ultrasound guidance. We propose a novel ultrasound-guided glossopharyngeal nerve block technique. Methods This new approach was performed in 3 patients in their twenties and thirties. A needle was inserted deeply under the stylohyoid muscle through the sternocleidomastoid muscle. Subsequently, an ultrasound-guided nerve block was performed with 1 mL of 1% xylocaine. The performance of our technique was evaluated with 2 tests: a cold sensitivity test and a gag reflex test. Results The effect of the nerve block was observed in the posterior third of the tongue on both sides, the tonsils, and the pharyngeal region. The effect lasted for approximately 1.5 hour. Motor efferent block was not observed. Conclusions We designated the technique as ultrasound-guided selective glossopharyngeal nerve block: posterior mandibular ramus approach. No complications occurred during the bilateral application. This novel approach can be performed at a very shallow position, compared with conventional methods. There is no damage to tissues other than the muscles, which reduces postoperative complications and patient distress. Although our technique requires further safety assessments and technical refinements, it could represent a simpler alternative to conventional methods in daily clinical practice. [ABSTRACT FROM AUTHOR]

Coupling red blood cell (RBC) supply to O2 demand is an intricate process requiring O2 sensing, generation of a stimulus, and signal transduction that alters upstream arteriolar tone. Although actively debated, this process has been theorized to be induced by hypoxia and to involve activation of endothelial inwardly rectifying K+ channels (KIR) 2.1 by elevated extracellular K+ to trigger conducted hyperpolarization via connexin40 (Cx40) gap junctions to upstream resistors. This concept was tested in resting healthy skeletal muscle of Cx40-/- and endothelial KIR2.1-/- mice using state-of-the-art live animal imaging where the local tissue O2 environment was manipulated using a custom gas chamber. Second-by-second capillary RBC flow responses were recorded as O2 was altered. A stepwise drop in PO2 at the muscle surface increased RBC supply in capillaries of control animals while elevated O2 elicited the opposite response; capillaries were confirmed to express Cx40. The RBC flow responses were rapid and tightly coupled to O2; computer simulations did not support hypoxia as a driving factor. In contrast, RBC flow responses were significantly diminished in Cx40-/- mice. Endothelial KIR2.1-/- mice, on the other hand, reacted normally to O2 changes, even when the O2 challenge was targeted to a smaller area of tissue with fewer capillaries. Conclusively, microvascular O2 responses depend on coordinated electrical signaling via Cx40 gap junctions, and endothelial KIR2.1 channels do not initiate the event. These findings reconceptualize the paradigm of blood flow regulation in skeletal muscle and how O2 triggers this process in capillaries independent of extracellular K+. [ABSTRACT FROM AUTHOR]

In this paper, detailed studies of effect of small amount of manganese substitution (at the zirconium site) on the structural, micro-structural, and electrical characteristics of lead zirconate titanate of Pb(Zr0.35–xMnxTi0.65)O3;x = 0, 0.02, 0.06, 0.10 (PZMT)) have been reported. The materials were prepared by using standard ceramic technology. The formation of the compounds and their basic crystal data have been studied through X-ray diffraction (XRD) method. The crystallite size and lattice strain of the compounds, evaluated from Scherrer's and Hall Williamson (H-W) equations, is found to be in the range of 40–50 nm and 11 × 10−4 to 50 × 10−4, respectively. Microstructures of different magnifications, revealing the surface nature of the compounds, have been recorded by field emission scanning electron microscope (FESEM). Effect of Mn+4 ions on electrical behavior (electrical impedance (Z*), electrical modulus (M*), conduction and relaxation phenomenon) of PZMT systems, over wide range of temperature and frequency, has been studied. [ABSTRACT FROM AUTHOR]

The Aswan cliff on Comet 67P/Churyumov–Gerasimenko collapsed on 2015 July 10. Thereby, relatively pristine comet material from a depth of |$\sim 12\, \mathrm{m}$| was exposed at the surface. Observations of the collapse site by the microwave instrument Rosetta /Microwave Instrument for Rosetta Orbiter (MIRO) have been retrieved from 8 months prior to collapse, as well as from 5, 7, and 11 months post-collapse. The MIRO data are analysed with thermophysical and radiative transfer models. The pre-collapse observations are consistent with a 30 MKS thermal inertia dust mantle with a thickness of at least |$3\, \mathrm{cm}$|⁠. The post-collapse data are consistent with (1) a dust/water–ice mass ratio of 0.9 ± 0.5 and a molar CO2 abundance of ∼30 per cent relative to water; (2) formation of a dust mantle after ∼7 months, having a thickness of a few millimetres or a fraction thereof; (3) a CO2 ice sublimation front at 0.4 cm that withdrew to 2.0 cm and later to |$20\pm 6\, \mathrm{cm}$|⁠ ; (4) a thermal inertia ranging 10–45 MKS; (5) a gas diffusivity that decreased from |$0.1$| to |$0.001\, \mathrm{m^2\, s^{-1}}$|⁠ ; and (6) presence of a solid-state greenhouse effect parts of the time. The data and the analysis provide a first empirical glimpse of how ice-rich cometary material ages and evolves when exposed to solar heating. [ABSTRACT FROM AUTHOR]

Open in new tab Download slide OBJECTIVES Postoperative neurocognitive disorder following thoracoscopic surgery with general anaesthesia may be linked to reduced intraoperative cerebral oxygenation and perioperative inflammation, which can potentially be exacerbated by mechanical ventilation. However, nonintubated thoracoscopic surgery, which utilizes regional anaesthesia and maintains spontaneous breathing, provides a unique model for studying the potential benefits of avoiding mechanical ventilation. This approach allows investigation into the impact on perioperative neurocognitive profiles, inflammatory responses and intraoperative cerebral oxygen levels. METHODS In total, 110 patients undergoing thoracoscopic surgery were randomly equally assigned to the intubated group and the nonintubated group. Regional cerebral oxygenation was monitored during surgery. Serum neuroinflammatory biomarkers, including interleukin-6 and glial fibrillary acidic protein, were measured at baseline (before surgery) and 24 h after surgery. Postoperative complication severity was compared using the Comprehensive Complication Index. The primary outcome was perioperative changes in neurocognitive test score, which was assessed at baseline, 24 h and 6 months after surgery. RESULTS Patients in the nonintubated group had higher neurocognitive test scores at 24 h (69.9 ± 10.5 vs 65.3 ± 11.8; P  =   0.03) and 6 months (70.6 ± 6.7 vs 65.4 ± 8.1; P  <   0.01) after surgery and significantly higher regional cerebral oxygenation over time during one-lung ventilation (P  =   0.03). Patients in the intubated group revealed a significantly higher postoperative serum interleukin-6 level (group by time interaction, P  =   0.04) and a trend towards a significantly higher serum glial fibrillary acidic protein level (group by time interaction, P  =   0.11). Furthermore, patients in the nonintubated group had a significantly lower Comprehensive Complication Index (9.0 ± 8.2 vs 6.1 ± 7.1; P  <   0.05). CONCLUSIONS Nonintubated thoracoscopic surgery was associated with improved postoperative neurocognitive recovery, more stable intraoperative cerebral oxygenation, ameliorated perioperative inflammation and attenuated postoperative complication severity. [ABSTRACT FROM AUTHOR]

Fully coupled heat transfer modeling during the thawing of frozen rock clefts yields melting rates that differ from those predicted by conventional conduction-based models. This research develops a conceptual model of a karst system subject to mountain permafrost supported by a numerical simulation incorporating free water convection. The numerical simulations rely on the apparent heat capacity method and the Darcy approach for energy and momentum equations. Notably, the anomalous behavior of water between 0 and 4? causes warmer meltwater to flow downwards, increasing the melting rate by approximately an order of magnitude as compared to conventional models that disregard free convection. The model outcomes are compared qualitatively with field data from Monlesi ice cave (Switzerland) and confirm the close agreement between the proposed model and real-world observations. [ABSTRACT FROM AUTHOR]

Zinc (Zn2+) is an essential element that can promote proper organ function, cell growth, and immune response; it can also, however, be present in too great a quantity. Zinc toxicity caused by overexposure may result in both minor and major physiological effects, with chronic exposure at low levels and acute exposure at high levels being harmful or even toxic. This investigation examines the effects of acute exposure to relatively high concentrations of Zn2+ on sensory nerve function and nerve conduction. A proprioceptive nerve in marine crab (Callinectes sapidus) limbs was used as a model to assess the effects of Zn2+ on stretch-activated channels (SACs) and evoked nerve conduction. Exposure to Zn2+ slowed nerve condition rapidly; however, several minutes were required before the SACs in sensory endings were affected. A depression in conduction speed and an increase followed by a decrease in amplitude were observed for the evoked compound action potential, while the frequency of nerve activity upon joint movement and stretching of the chordotonal organ significantly decreased. These altered responses could be partially reversed via extensive flushing with fresh saline to remove the zinc. This indicates that subtle, long-term exposure to Zn2+ may alter an organism’s SAC function for channels related to proprioception and nerve conduction.

Animals are exposed to lithium (Li+) in the natural environment as well as by contact with industrial sources and therapeutic treatments. Low levels of exposure over time and high volumes of acute levels can be harmful and even toxic. The following study examines the effect of high-volume acute levels of Li+ on sensory nerve function and nerve conduction. A proprioceptive nerve in the limbs of a marine crab (Callinectes sapidus) was used as a model to address the effects on stretch-activated channels (SACs) and evoked nerve conduction. The substitution of Li+ for Na+ in the bathing saline slowed nerve conduction rapidly; however, several minutes were required before the SACs in sensory endings were affected. The evoked compound action potential slowed in conduction and slightly decreased in amplitude, while the frequency of nerve activity with joint movement and chordotonal organ stretching significantly decreased. Both altered responses could be partially restored with the return of a Na+-containing saline. Long-term exposure to Li+ may alter the function of SACs in organisms related to proprioception and nerve conduction, but it remains to be investigated.

The cluster of galaxies Abell 2146 is undergoing a major merger and is an ideal cluster to study intracluster medium (ICM) physics, as it has a simple geometry with the merger axis in the plane of the sky, its distance allows us to resolve features across the relevant scales and its temperature lies within Chandra 's sensitivity. Gas from the cool core of the subcluster has been partially stripped into a tail of gas, which gives a unique opportunity to look at the survival of such gas and determine the rate of conduction in the ICM. We use deep 2.4-Ms Chandra observations of Abell 2146 to produce a high spatial resolution map of the temperature structure along a plume in the ram-pressure stripped tail, described by a partial cone, which is distinguishable from the hot ambient gas. Previous studies of conduction in the ICM typically rely on estimates of the survival time for key structures, such as cold fronts. Here we use detailed hydrodynamical simulations of Abell 2146 to determine the flow velocities along the stripped plume and measure the time-scale of the temperature increase along its length. We find that conduction must be highly suppressed by multiple orders of magnitude compared to the Spitzer rate, as the energy used is about 1  per cent of the energy available. We discuss magnetic draping around the core as a possible mechanism for suppressing conduction. [ABSTRACT FROM AUTHOR]

This study presents a novel methodology for determining the apparent thermal diffusivity of subsoil in situ, employing two heat transfer models within the subsurface: one method is based on heat conduction caused by air temperature oscillations, while the other considers heat transmission via both conduction and convection due to groundwater flow. Differential equations were solved, and non-linear regression analysis was employed. This method has direct applications in various engineering and environmental domains, such as underground transmission lines, oil and gas pipelines, radioactive waste management, and geothermal systems, especially in the context of implementing horizontal geothermal collectors (HGC). The apparent thermal diffusivity value of 1.514 × 10−6 m2 s−1, within a 95% confidence interval spanning 1.512 × 10−6 m2 s−1 and 1.516 × 10−6 m2 s−1, was obtained from the section between 1.67 and 3.86 m depth in a research borehole located in Asturias, Northern Spain, using twenty-one temperature sensors. The method allowed for the calculation of the subsoil's apparent thermal diffusivity up to a depth of 14.55 m. [ABSTRACT FROM AUTHOR]

Introduction: Atherosclerosis in patients with type 1 diabetes starts early in childhood with subclinical abnormalities. The epicardial fat thickness (EFT) is a novel method for detecting these early changes. Furthermore, electrocardiographic markers may be altered in patients with diabetes owing to early cardiovascular changes. This study aimed to determine the relationship between EFT and electrocardiographic markers in children with type 1 diabetes mellitus. Methods: Children with type 1 diabetes who were followed up at the Alexandria University Children’s Hospital Diabetes Clinic were enrolled in this study. The study recruited three groups of participants, including 20 patients with a diabetes duration of less than 5 years, 20 patients with a diabetes duration of 5 years or more, and 20 healthy controls. All participants were evaluated with emphasis on anthropometric measurements, fasting blood glucose levels, and lipid profile. HbA1c levels were measured in the cohort with diabetes. All participants underwent electrocardiography for measurement of P-wave dispersion, corrected QT interval and its dispersion, and Tp-e measurement. Echocardiography was performed to measure the EFT. Results: Among all participants, EFT was significantly higher in children with a diabetes duration of ≥5 years (p = 0.009). Furthermore, P-wave dispersion was significantly prolonged in children with diabetes compared to that in nondiabetics (p = 0.041). There was a statistically significant correlation between EFT and P-wave dispersion in patients with diabetes aged ≥5 years (p = 0.021). Conclusions: Measurement of EFT by echocardiography is a novel and easy way to predict early cardiovascular changes in children with diabetes, including conduction system disorders. [ABSTRACT FROM AUTHOR]

The interaction of bio–geosphere dates to the formation of first unicellular microbes on earth. However, it is only relatively recently that the complex biological interactions are observed, characterised, and simulated for its use in the domain of geotechnical engineering. Also, many bioinspired approaches have been utilised in computational geotechnics for optimisation and data analysis process. The living phase present in the soil system hold a bearing on the majority of geochemical reactions and assist in modifying its fundamental and engineering behaviour. It necessitates revaluation and rescrutinisation of the conventional theories and formulations in geotechnical engineering, where soil has always been considered as an inert engineering material from biological perspective. To that end, this manuscript provides a critical review on biological approaches used in geotechnical engineering by highlighting the ongoing developments, achievements, and challenges to implement the processes. The review further emphasises the role of biological systems on the alteration of fundamental properties of soils and their consequences on effective stress, strength and stiffness, volume change and conduction properties of soils. Overall, the manuscript provides a basic understanding on the biological intervention in the soil system and the importance of consideration of the fourth phase in the soil system, i.e., the living phase, while describing such interventions. [ABSTRACT FROM AUTHOR]

Reliable experimental data is essential for reproducible science. As our lab has access to five instruments of the isothermal (heat conduction) type of different age and product generations, we became interested in the quality of experimental data obtained from the different instruments. Each instrument consists of 8 individual calorimeters. An intralaboratory study of the first 72 hours of cement hydration was conducted with all five instruments. The objective was to determine the differences between the available instruments with respect to repeatability (precision of the 8 calorimeters within one instrument) and reproducibility (precision between the different instruments). The experimental program comprises 120 calorimetry runs in total (5 instruments each with 8 calorimeters, triple measurement performed). Results show that the oldest instrument version with its 8 calorimeters has a stronger higher standard deviation of the heat released after 72 hours compared to the latest state‐of‐the‐art instrument model (246.7 ± 2.7 vs. 232.3 ± 0.5 Jg–1). This is attributed to the technical design differences of the instruments and continuous use over time. In terms of reproducibility, an increasing standard deviation for the heat released from 1 day to 3 days (136.2 ± 2.6 and 236.4 ± 5.9 J g–1) is observed. From our point of view, this test study indicates that isothermal heat conduction calorimetry is a robust and precise measurement method to determine the heat of cement hydration for 72 hours. [ABSTRACT FROM AUTHOR]

• Modification of the earth albedo measurement model. • Verification of the enhanced measurement model using Thermal Desktop and SINDA software. • Investigation the effect of surface conduction on the attitude estimation accuracy. • Comprehensive sensitivity analysis with respect to the various system parameters. Accurate attitude information of satellites is a prerequisite for many space missions requiring some pointing capabilities. A radiation-based (RB) thermopile measurement package has recently been proposed for satellite attitude estimation with potential cost and power benefits. However, previous related researches have not considered all modes of the thermal communication, and have specifically neglected the conduction effect on and between the satellite surfaces as a simplifying assumption to initially develop the innovative measurement equation. As this assumption is practically difficult to implement for contemporary satellites operating in near Earth space environment, the present work complements the effect of conduction terms both in the measurement model as well as in relations pertaining to the solar RB attitude knowledge. In addition, another simplifying assumption of constant Earth albedo factor (AF) is also removed. Moreover, the present study simultaneously estimates the satellite attitude as well as its surface's thermal characteristics (TC). The stochastic estimation algorithm used in the current study is based on the unscented Kalman filter (UKF) for attitude estimation via the new proposed sensor pack and measurement model. Finally, the study is augmented with a thorough sensitivity analysis against satellite internal heat radiation, environmental and initial conditions that have been verified via Monte Carlo simulations (MCS) to assess the merits of the proposed modified thermal model for RB concurrent satellite attitude and TC estimations. [ABSTRACT FROM AUTHOR]

McMahon, G, and Kennedy, R. The effects of palm cooling on physiological and metabolic responses, exercise performance, and total volume during high-intensity bench press exercise in resistance-trained men. J Strength Cond Res 37(11): 2122-2129, 2023--Previous research suggests that cooling distal to the working agonist muscles during the interset rest periods of highintensity resistance exercise may facilitate improved performance by means of improving metabolic conditions of contractile machinery. However, these studies have not directly measured indicators of metabolic conditions. Therefore, the aim of this study was to compare 2 palm-cooling conditions with a thermoneutral condition during high-intensity resistance exercise and subsequent effects on physiological and metabolic responses and exercise performance. Eleven healthy, resistance-trained, young men (20-36 years old) performed 4 sets of bench press exercise to exhaustion at 80% 1 repetition maximum each separated by 3 minutes of passive recovery. Palm cooling (10° C [TEN] or 15° C [FTN]) or thermoneutral (28° C [CON]) condition was applied for 60 seconds during the recovery interval of each set in a randomized, double-blind fashion, with 4 days recovery between the experimental conditions. There were no differences (p. 0.05) in volume load between the experimental conditions across all sets. Mean repetition velocity and force of the bench press declined significantly following set 1 in all conditions (p,0.05), but there were no differences between the conditions. Lactate, heart rate, and rating of perceived exertion systematically increased from sets 1 to 4; however, there were no significant differences (p.0.05) between any of the conditions. Palm cooling at either 10 or 15° C had no observable effects on physiological and metabolic responses during exercise, nor has it any effect on bench press performance or volume load compared with a thermoneutral condition. Therefore, cooling cannot be currently recommended as an ergogenic strategy to enhance acute bench press performance or mitigate fatigue during high-intensity resistance training. [ABSTRACT FROM AUTHOR]

Resistive switching devices are candidates to be used as weight for the future hardware realization of neuronal networks. Herein, these resistive switches base on oxygen vacancy migration and can be toggled between different resistance states. Internal processes lead to a variability over time in these states. To understand this, a dynamical model is developed, which links the internal physical mechanism to the current response. Thereby, the electronic current is calculated by tunneling processes over oxygen vacancies. The model allows to understand the physical transport properties and the current–voltage dependence. Integrating ionic hopping processes clarifies the variability in the electronic conduction. The derived model does not require empirical input parameters and only depends on the properties of the materials. This allows to use literature values and independently compare them to electrical measurements. The model predicts the experiments correctly. Thereupon, the physical properties of the conduction are investigated with respect to the transport over discrete energy levels, which change under the hopping of oxygen vacancies. Afterwards, the current level and variability are simulated for increasing oxygen vacancy concentrations to investigate analog switching, which is required for neuronal network layers. Finally, the variability is tested with multiple interacting cells in a neuronal layer. [ABSTRACT FROM AUTHOR]

The need to improve access to health services for the transgender community has become evident, especially concerning cardiovascular risk, which is higher compared to the general population. Surgical procedures and hormone therapies are common in this population to affirm gender identity, but they pose challenges as they are associated with disruptions in lipid metabolism, body fat concentration, and insulin resistance. Additionally, there is an increased risk of adverse cardiovascular events such as venous thromboembolism, stroke, and myocardial infarction. The influence of sex hormones on the electrophysiological properties of the heart has been studied, highlighting gender differences that may predispose the transgender population to cardiac arrhythmias. Exogenous hormone therapy, for both transgender women and men, can affect the QT interval and increase the risk of arrhythmias, including atrial fibrillation. Although the incidence of arrhythmias in the transgender population is not entirely clear, evidence suggests the need for careful cardiovascular monitoring and consideration of risk factors before initiating hormone therapies. [ABSTRACT FROM AUTHOR]

Myotonic dystrophy type 1 (DM1) is a genetic disorder that causes muscle weakness and myotonia. In DM1 patients, cardiac electrical manifestations include conduction defects and atrial fibrillation. DM1 results in the expansion of a CTG transcribed into CUG-containing transcripts that accumulate in the nucleus as RNA foci and alter the activity of several splicing regulators. The underlying pathological mechanism involves two key RNA-binding proteins (MBNL and CELF) with expanded CUG repeats that sequester MBNL and alter the activity of CELF resulting in spliceopathy and abnormal electrical activity. In the present study, we identified two DM1 patients with heart conduction abnormalities and characterized their hiPSC lines. Two differentiation protocols were used to investigate both the ventricular and the atrial electrophysiological aspects of DM1 and unveil the impact of the mutation on voltage-gated ion channels, electrical activity, and calcium homeostasis in DM1 cardiomyocytes derived from hiPSCs. Our analysis revealed the presence of molecular hallmarks of DM1, including the accumulation of RNA foci and sequestration of MBNL1 in DM1 hiPSC-CMs. We also observed mis-splicing of SCN5A and haploinsufficiency of DMPK. Furthermore, we conducted separate characterizations of atrial and ventricular electrical activity, conduction properties, and calcium homeostasis. Both DM1 cell lines exhibited reduced density of sodium and calcium currents, prolonged action potential duration, slower conduction velocity, and impaired calcium transient propagation in both ventricular and atrial cardiomyocytes. Notably, arrhythmogenic events were recorded, including both ventricular and atrial arrhythmias were observed in the two DM1 cell lines. These findings enhance our comprehension of the molecular mechanisms underlying DM1 and provide valuable insights into the pathophysiology of ventricular and atrial involvement. [ABSTRACT FROM AUTHOR]

A simultaneous heat and mass transfer model based on global coefficients was proposed to describe the oil absorption, water loss, and temperature changes occurring during the post-frying period of potato cylinders. The model was solved in Matlab® and simultaneously fitted to post-frying kinetics from literature, describing the surface and penetrated surface oil contents, as well as the surface and centre temperatures of potato cylinders at six holding temperatures (25, 100, 120, 140, 160, and 180°C). Besides, simple algorithms were developed to evaluate the oil layer thickness and the minimum oil penetration distance, obtained by assuming the potato cylinder was split into a dry zone, where the oil was absorbed, and a moist zone free from oil. The model achieved a good reproduction of fitted responses with average deviations ranging from 1.9 to 11.7% for all post-frying holding temperatures. Estimated distribution coefficients evidenced higher oil absorption at low holding temperatures, increasing from 0.66 kg surface oil/kg absorbed oil at 25°C to 2.60 kg surface oil/kg absorbed oil at 180°C, while no temperature influence on mass transfer coefficient was found under the explored experimental conditions (p > 0.05). The estimated minimum oil penetration distance (thickness of the dry zone region) after the post-frying stage (229 to 506 µm) showed a good agreement with crust thickness values from literature. [ABSTRACT FROM AUTHOR]

The orthodox view holds that analogical arguments are a distinctive type of argument, while the eliminative view and its enhanced variant proposed in this paper contend that analogical arguments can be reducible to non-analogical arguments by eliminating the similarities proposition. This paper shows that the existing defense for the orthodox view fails to tackle the challenge posed by the eliminative view and its enhanced variant. The new defense for the distinctiveness of analogical arguments argues that an analogical argument is composed of both a conductive and principle-based argument. Consequently, analogical arguments remain irreducible, as the similarities proposition is not eliminated.

PURPOSE OF REVIEW: The field of regional anesthesia has evolved tremendously in the last 15 years. New anesthesia protocols for ambulatory surgery and enhanced recovery after surgery have been developed as well. The focus of these techniques and protocols has centered on patient satisfaction and pain control while minimizing the use of opioids. The field of ambulatory surgery and anesthesia continues to evolve, and regional anesthesia and its plane techniques are at the center of these changes. RECENT FINDINGS: Recent research has shown that regional techniques contribute to better pain control and patient experience and may decrease patient readmission rates. The safety of these techniques has been validated when performed by experienced practitioners. New techniques such as the erector spinae block (ESP) have been studied in the setting of laparoscopic surgery with promising results. Regional anesthesia techniques for patients presenting for laparoscopic surgery are safe and seem to provide benefits. Those are related to patient experience, pain control, and readmission rates. Different techniques can be applied to a specific type of intervention. Application of these techniques depend on the clinical picture and patient. Future research may help us clarify how these techniques may improve patient satisfaction and operating room efficiency. New regional blocks may also develop based on what we know today.