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The effect of transcranial alternating current stimulation (tACS) on major depressive disorder (MDD) was not confirmed. To evaluate the feasibility, safety, and efficacy of tACS as an add-on treatment for the symptoms of depression and to understand how tACS affects brain activity. The 4-week, double-blind, randomized, sham-controlled trial was performed from January 29, 2023 to December 22, 2023. Sixty-six participants were recruited and randomly assigned to receive 20 40-min sessions of either active (77.5Hz, 15 mA) or sham stimulation, with one electrode on the forehead and two on the mastoid, each day (n = 33 for each group) for four weeks (till Week 4). The participants were followed for 4 more weeks (till Week 8) without stimulation for efficacy/safety assessment. During the 4-week trial, all participants were required to take 10–20 mg of escitalopram daily. The primary efficacy endpoint was the change in HAMD-17 scores from baseline to Week 4 (with 20 treatment sessions completed). Resting-state electroencephalography (EEG) was collected with a 64-channel EEG system (Brain Products, Germany) at baseline and the Week 4 follow-up. The chi-square test, Fisher's exact test, independent-sample t -test, or Wilcoxon rank-sum test were used, as appropriate, to compare the differences in variables between groups. The effect of the intervention on the HAMD-17 score was also evaluated with linear mixed modeling (LMM) as sensitivity analysis. The correlation between the mean reduction in EEG and the mean reduction in the HAMD-17 total score was evaluated using Spearman correlation analysis. A total of 66 patients (mean [SD] age, 28.4 [8.18] years; 52 [78.8 %] female) were randomized, and 57 patients completed the study. Significant differences were found in the reductions in the HAMD-17 scores at Week 4 (t = 3.44, P = 0.001). Response rates at Week 4 were significantly higher in the active tACS group than in the sham tACS group (22 out of 33 patients [66.7 %] versus 11 out of 33 [33.3 %], P = 0.007). In the active tACS group, a correlation between the mean change in alpha power and HAMD-17 scores at Week 4 was found (r = 2.38, P = 0.024), and the mean change in alpha power was significantly bigger for responders (Z = 2.46, P = 0.014). No serious adverse events were observed in this trial. The additional antidepressant effect of tACS is significant, and the combination of tACS with antidepressants is a feasible and effective approach for the treatment of MDD. The antidepressant mechanism of tACS may be the reduction in alpha power in the left frontal lobe. Future research directions may include exploring more appropriate treatment parameters of tACS. • Add-on tACS can enhance efficacy compared to antidepressant monotherapy in acute treatment. • Long-lasting additional antidepressant effect of tACS for at least 4 weeks. • The decrease in left frontal alpha power was found in patients who responded to tACS treatment. • The antidepressant mechanism of tACS may be the reduction in alpha power in the left frontal lobe. [ABSTRACT FROM AUTHOR]

• A nonlocal fractional bio-thermoelastic model is developed based on fractional Pennes model and nonlocal elasticity theory. • The heat conduction process and deformation in biological tissue under the action of a pulsing heat flux are investigated. • The effects of pulse characteristic time, fractional order and nonlocal elastic parameters on the responses are discussed. A nonlocal fractional bio-thermo-mechanical model is developed in the context of modified fractional Pennes equation and nonlocal elasticity theory of Eringen. In the example analysis, a one-dimensional homogeneous and isotropic biological tissue model is assumed and the solutions of coupling fractional bio-thermo-mechanical equations are obtained by the method of Laplace transform. The heat conduction process and deformation in biological tissue under the action of a pulsing heat flux are investigated. The influences of fractional order parameter, pulsing heat flux characteristic time and nonlocal elastic parameter on the heat transfer, heat-induced deformation and thermal stress are analyzed. [ABSTRACT FROM AUTHOR]

ESPEN/EASO advocates screening for sarcopenic obesity based on the concomitant presence of an elevated body mass index (BMI) or waist circumference. Neck circumference (NC) is another simple and reliable anthropometric measurement for estimating obesity; however, its ability to detect sarcopenic obesity has not yet been established. The aim of the present study was to explore the association between NC and sarcopenic obesity in a Shanghai community population. The study included 1542 participants (622 men and 920 women) with a mean age of 58 years who underwent an examination for the detection of obesity at baseline in 2013–2014 and received a re-examination in 2015–2016. An automatic bioelectric impedance analyzer was used to estimate body composition, and magnetic resonance imaging was used to measure abdominal fat distribution. The definition of pre-sarcopenic obesity combined low skeletal muscle mass adjusted by weight (SMM/W) with obesity which defined according to overall adiposity or fat distribution as BMI ≥25 kg/m2, fat percentage (fat%) ≥ 25% in men and 30% in women, or visceral fat area (VFA) ≥ 80 cm2, respectively. In both men and women, subjects with low SMM/W had a higher level of NC than those without (both P < 0.01). In turn, participants with elevated NC had a higher proportion of pre-sarcopenic obesity in both men and women, regardless of adiposity status assessed by BMI, fat%, or VFA (all P < 0.01). During an average follow up of 2.1 years, for each 1 cm increase in NC, multivariable-adjusted hazard ratios of pre-sarcopenic obesity in which adiposity status assessed by high BMI were 1.40 (1.11–1.76) in men and 1.32 (1.13–1.56) in women; in addition, such association remained between NC and pre-sarcopenic obesity assessed by high fat% or high VFA. NC is closely associated with the incidence of sarcopenic obesity, suggesting that it could be helpful for screening sarcopenic obesity in a community-based population. [ABSTRACT FROM AUTHOR]

The microstructure and oxidation resistance of NiAlHf and NiAlHfY coatings were systematically investigated at 1200 °C in air. The results revealed that Hf-rich oxides, Y-rich oxides, (Hf, Y)-rich oxides distributed at grain boundaries of oxide scale for NiAlHfY coating, which improved the adhesion and spallation resistance of oxide scale. And oxidation weight gains of NiAlHf, NiAlHfY coatings were 2.2425 and 1.8231 mg cm−2, respectively, which was reduced by 18.7% after Y-doping. The enhanced oxidation resistance was attributed to better synergistic effect of Hf and Y impeding ions diffusion. Finally, the Y-doping mechanism responsible for enhanced oxidation resistance was discussed. [ABSTRACT FROM AUTHOR]

The incidents of Aurelia sp. stinging have recently increased because of a bloom in offshore area. However, their symptoms are much milder than those from another scyphozoan jellyfish, Stomolophus meleagris. The molecular composition of the medusa and polyp of Aurelia coerulea was analyzed by sequencing the transcriptome and proteome. The toxicity of tentacle extract from A. coerulea medusa (A-TE) and S. meleagris medusa (S-TE) was measured by the survival rates of mice, their blood indexes, and integrity of red blood cells. The medusa and polyp of A. coerulea are similar in molecular composition, while their gene expressions are significantly different at both transcriptome and proteome levels. A-TE displayed no in vitro hemolysis and caused mild damage to the liver, heart and kidney instead of lethality. In contrast, S-TE showed strong hemolytic toxicity, and lethal effect with serious damage to the liver, heart and kidney. The toxin screening in the medusae showed that there were similar toxin categories though the number of toxin species in A. coerulea was larger than that in S. meleagris. Among them, lactotransferrin and venom prothrombin activator were the two predominant protein toxins in the medusae of A. coerulea and S. meleagris , respectively. A. coerulea medusa and polyp have similar molecular compositions, though there are observable morphological differences. The toxicity of A. coerulea medusa is significantly weaker than that of S. meleagris medusa of which the variation in toxin expressions is feasibly an important reason. [Display omitted] • There was little difference in gene function between Aurelia coerulea medusa and polyp. • Compared with Stomolophus meleagris , A. coerulea caused milder liver, heart and kidney damages without lethality. • Lactotransferrin and venom prothrombin activator were the predominant proteins in A. coerulea and S. meleagris , respectively. [ABSTRACT FROM AUTHOR]

• The fractional linear thermo-viscoelastic theory of biological tissue with dual phase lag model is developed. • The fractional relaxation effects of heat conduction and viscoelastic constitutive relation are considered. • The transient coupling thermal and mechanical behavior of biological tissue is investigated. • The effects of fractional parameters on the responses are discussed. Viscoelasticity is an inherent property of the biological tissue and is often used as a diagnosis parameter in characterizing cancer. Recently, it has been found that fractional calculus agrees well with experimental results when describing the viscoelastic materials. In this study, the fractional linear thermo-viscoelastic theory is developed with considering the fractional relaxation effect of dual phase lag heat conduction model and viscoelastic constitutive relation simultaneously. The transient coupling thermal and mechanical behavior of biological tissue are investigated. The governing equations are solved by Laplace transformation. The effects of fractional parameter on the distributions of temperature, displacement and stress are obtained and illustrated graphically. [ABSTRACT FROM AUTHOR]

[Display omitted] • A porphyrin-conjugated lignin photosensitizer TCPP- g -AL-NPs for aPDT was obtained. • TCPP- g -AL-NPs showed high photodynamic antibacterial activity and biocompatibility. • The p-n heterostructure of TCPP- g -AL-NPs promoted the single oxygen generation. This work explores the potential of porphyrin-grafted lignin nanoparticles (TCPP- g -AL-NPs) as a novel, effective, and biocompatible photosensitizer for antibacterial applications. Lignin acted as a sustainable framework, enhancing water-compatibility and single oxygen (1O 2) generation of porphyrin. The mechanism study revealed the successful formation of a p-n heterojunction between lignin and porphyrin, which promoted the charge separation and the photocatalytic process of O 2 to 1O 2. In vitro antibacterial assessments demonstrated the efficacy of TCPP- g -AL-NPs in eradicating both Gram-negative (E. coli) and Gram-positive (S. aureus) bacteria under blue LED light irradiation. The observed lower antibacterial effectiveness against E. coli compared to S. aureus could be attributed to the thicker cell membrane of Gram-negative bacteria. Additionally, TCPP- g -AL-NPs exhibited no cytotoxicity towards mouse fibroblast cells (L929). This study presents a straightforward and promising approach for developing lignin-based photosensitizers for photodynamic therapy. [ABSTRACT FROM AUTHOR]

Given the escalating environmental challenges and the looming carbon peaking and carbon neutrality goals, developing renewable energies becomes a global imperative. The pivotal initial stage involves site selection; however, this process has been plagued by the ambiguity of subjective decision-making and the inconsistency of multi-factor decisions. In this regard, this study proposes a new evaluation system which combines Geodetector and Interaction Linear Model to minimize subjective interventions and reveal the mechanisms by which interaction terms influence siting. China is selected to unveil the model's capability through solar PV site selection. The results indicate that compared with the Basic Linear Model, the Interaction Linear Model increased the estimation accuracy by 8%, with some interactive terms showing higher determinant power than single factors. Based on this interaction model, there is a total of 13% of China's land is developable for solar PV plants, consisting of 46% highly suitable areas (581,576 km2), 39% moderately suitable areas (492,615 km2), and 15% marginally suitable areas (198,088 km2). Finally, Xinjiang was identified as the most suitable place in China. Above all, the new siting system proposed here provides a new perspective on renewables' site selection, promoting the high-quality energy transition globally. • A new siting system integrating Geodetector and Interaction Linear Model minimizes subjectivity and improves performance. • A case study in China for solar PV site selection reveals 8% improved estimation accuracy with the interaction model. • Certain interactive terms exhibit higher determinant power than single factors. • 13% of China's land is developable for PV, with 46% highly suitable, 39% moderately suitable, and 15% marginally suitable. [ABSTRACT FROM AUTHOR]

• The dual phase lag thermo-viscoelastic model is developed in this work. • Transient thermo-mechanical responses of the tumor-normal tissues are investigated. • The effects of relaxation time and viscoelastic property are discussed. Although viscoelastic properties of biological tissue has been reported in many articles, no effort has been made to investigate the coupled thermal and mechanical behavior of biological tissue based on the viscoelastic theory. This provides us a motivation to study the transient thermoelastic coupling response in the context of generalized thermo-viscoelastic model. The dual phase lag thermo-viscoelastic model is established to capture the micro-scale responses of biological tissue. The governing equations are solved by Laplace transformation. The effects of relaxation times and viscoelastic property on the responses of the tumor and normal tissues are discussed and illustrated graphically. According to the numerical results, we can obtain (1) the viscoelastic parameter has a significant effect on the distributions of displacement and stress; (2) the lagging thermo-viscoelastic responses depend not only on the ratio of τ t /τ q , but also on the absolute values of τ t and τ q. [ABSTRACT FROM AUTHOR]

• Influence of aggregate gradation and distribution on bond curve can be ignored. • The damage area at the concrete section increases as the slip increases. • Bond strength and slip decrease as temperature increases at same initial stress. • Heating and loading sequence have a significant effect on bond performance. The bond performance between steel and concrete exposed to fire is influenced by many factors, including the presence of an initial load before the temperature increase. To investigate such effect, a 3-D refined simulation model is presented accounting for the heterogeneity of concrete at the mesoscopic level and the external geometry of ribbed steel bars. The rationality and validity of the refined simulation model and of the multi-step analysis were verified by comparison with existing experimental data. Subsequently, the effects of aggregate gradation and distribution, initial loading level and temperature on the bond behavior were analyzed. The load transfer mechanism at the steel–concrete interface as a function of temperature under different loading levels is captured and discussed. It is found that the influence of aggregate grading and distribution on the bond-slip curve can be ignored under the aggregate volume fraction set in this work. Additionally, results show that the damage initially concentrates at the rib tip of the deformed steel bars, with an increase across the concrete section as the slip increases, as it could be expected. However, the bond stress and both stress and strain of steel at the same position decrease as the temperature increases. Finally and most importantly, it is found that the heating and loading sequence induce a different damage evolution inside the specimen, with a significant effect on the bond stiffness, the plateau portion of the bond stress-slip curve and the bond strength associated to a given critical temperature. [ABSTRACT FROM AUTHOR]

• Integrated model of ICE and CTPC in GT-SUITE calibrated against experimental data. • Performance prediction of four CTPC system layouts under a cruise driving cycle. • Control structure of mode switch module and PID controllers are proposed. • CTPC systems show strong robustness against highly transient heat sources. • Enhancing pump and turbine performance facilitates CTPC integration with ICE. Carbon dioxide transcritical power cycle (CTPC) systems are considered a new and particularly interesting technology for waste-heat recovery. In heavy-duty truck engine applications, challenges arise from the highly transient nature of the available heat sources. This paper presents an integrated model of CTPC systems recovering heat from a truck diesel engine, developed in GT-SUITE software and calibrated against experimental data, considers the likely fuel consumption improvements and identifies directions for further improvement. The transient performance of four different CTPC systems is predicted over a heavy-heavy duty driving cycle with a control structure comprising a mode switch module and two PID controllers implemented to realize stable, safe and optimal operation. Three operating modes are defined: startup mode, power mode, and stop mode. The results demonstrate that CTPC systems are robust and able to operate safely even when the heat sources are highly transient, indicating a promising potential for the deployment of this technology in such applications. Furthermore, a system layout with both a preheater and a recuperator appears as the most promising, allowing a 2.3% improvement in brake thermal efficiency over the whole driving cycle by utilizing 48.9% of the exhaust and 72.8% of the coolant energy, even when the pump and turbine efficiencies are as low as 50%. Finally, factor analysis suggests that important directions aimed at improving the performance and facilitating CTPC system integration with vehicle engines are: (1) ensuring long-duration operation in power mode, e.g., by employment in long-haul trucks; and (2) enhancing pump and turbine performance. [ABSTRACT FROM AUTHOR]

Abstract A large number of studies indicate that blood perfusion rate in biological tissue cannot be regarded as a constant in burn and thermal therapy analysis. This provides us a motivation to investigate the transient responses in the context of generalized bio-thermoelastic theories with temperature dependent blood perfusion rate. It is difficult to obtain the analytical solutions of nonlinear governing equations due to the consideration of variable blood perfusion rate. In present work, the finite element control equations of skin tissue based on generalized bio-thermoelasticity are derived and the nonlinear thermoelastic responses of the triple-layered skin tissue are obtained in time-domain directly. The influences of variable blood perfusion rate on the responses are discussed and illustrated graphically. Highlights • Responses of skin tissue is studied based on generalized bio-thermoelastic theories. • A triple-layered model with variable blood perfusion rate is used in this study. • The finite element method is used in solving these nonlinear governing equations. [ABSTRACT FROM AUTHOR]

Abstract Carbon dioxide transcritical power cycle (CTPC) systems are dynamically tested on a constructed test bench using an expansion valve. Effects of external perturbations of pump speed, expansion valve opening and engine conditions on dynamic performance of the CTPC systems are investigated with step changes. Dynamic characteristics are identified with rise time, settling time and overshoot. Results show that both a basic CTPC system and a CTPC system with a recuperator (R-CTPC) behave as a second-order underdamped system with the perturbations of pump speed and expansion valve opening. Overshoot or undershoot tends to appear in pressures when pump speed changes, while overshoot or undershoot occurs more noticeably in temperatures when expansion valve opening varies. Although the CTPC systems respond slowly with the perturbations of engine conditions, they have the ability to operate safely and produce power continuously. Therefore, the CTPC systems are robust when facing narrow fluctuations of heat sources while swift when required to make adjustments, showing great potential for truck engine waste heat recovery. Overall, current research gives a full understanding of the dynamic performance of the CTPC systems, which will provide references for dynamic model validation and possible control strategy identification. Highlights • Perturbations include pump speed, expansion valve opening, engine speed and torque. • Effects on dynamic performance of CTPC and R-CTPC are tested with step changes. • CTPC systems behave as a second-order underdamped system and overshoot occur. • CTPC systems respond fast with variations of pump speed and expansion valve opening. • CTPC systems are robust facing narrow fluctuations while swift when needs to adjust. [ABSTRACT FROM AUTHOR]

• Shape of the bond-slip curve is closely related to the concrete cover thickness. • Ultimate bond strength at or after the fire showed opposite changes with 400 °C. • Stress of the rebar at high temperatures is greater than that after cooling down. • Formulations that can predict bond strength and slip exposure to fire was proposed. The refined numerical simulation method was used to study the influences of the concrete cover and the diameter of the rebar on the bond-slip properties of deformed reinforced concrete under two fire scenarios. The feasibility and rationality of the refined simulation method were verified by comparison with the experimental results. Subsequently, the influences of the concrete protective layer thickness and the diameter of the rebar on specimen failure pattern, bond failure mechanism, bond-slip curve, and the distribution of the stress and strain for the steel were investigated. The effects of parameters on ultimate, residual bond strength and ultimate slip were mainly discussed. The results show that the failure pattern of the specimen exposure to heat conditions changes from concrete splitting to steel bar pull-out as the concrete cover thickness increases; the shape of the bond-slip curve was affected by the concrete cover thickness, regardless of the fire scenario, rebar diameter and the target temperature. As the rebar diameter increased, the bond strength at high temperatures and after cooling down decreased when the specimen experienced the same temperature. Finally, the formulation for the bond strength and slip at high temperatures and after cooling down was suggested by comparing with the experimental and calculated results, which can take into account the thickness of the concrete protection layer, the diameter of the reinforcement bar, the fire scenario and the temperature. [ABSTRACT FROM AUTHOR]

Copper-graphite composites find extensive application as electrical contact materials. However, their tribological properties are limited by the weak interfacial bonding. In this study, Ti 3 AlC 2 was used to modify copper-graphite composites fabricated by vacuum sintering. The incorporation of Ti 3 AlC 2 included both coated Cu and uncoated Cu. The hardness, relative density, tribological properties, and microstructure of the composites were thoroughly investigated. The results show that the addition of Ti 3 AlC 2 coated with Cu was conducive to avoiding the agglomeration of Ti 3 AlC 2 particles, and resulting in superior relative density, hardness, lubrication and wear resistance of the composites. Furthermore, the incorporation of Ti 3 AlC 2 not only enhanced the presence of lubricating components in copper-graphite composites but also improved the interface bonding strength between the copper matrix and graphite. Specifically, Cu-graphite-Ti 3 AlC 2 (Cu-coated) composites displayed a relative density of 92%, a hardness of 94.2 HV, a friction coefficient of 0.175, and a wear rate of 1.28 × 10−6 mm3/N·m. • Graphite and Ti 3 AlC 2 were used to synergistically reinforce copper matrix composites. • The microstructure and properties of Cu-graphite-Ti 3 AlC 2 composites were investigated. • The interfacial bonding between copper and graphite was improved. [ABSTRACT FROM AUTHOR]