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Given the practical issues of the traditional power system's insufficient operational flexibility in the face of changing residential power load and source-side output, demand response can effectively improve the flexibility, safety and economic benefits of system operation. The value of demand response is especially noticeable meanwhile the refined assessment of demand response potential is an important basic support. A method is proposed about evaluating aggregate demand response potential in the absence of historical demand response data based on Gaussian mixture model. Firstly, the typical data are selected through two-stage clustering of households and similar days to improve data representativeness. Then the Gaussian mixture model is introduced to accurately explore the probability distribution of household electricity consumption behavior and calculate individual households' demand response potential. Finally, the bottom-up weighted aggregation is implemented to evaluate the aggregate demand response potential under multiple confidence scenarios. According to empirical analysis, this method can mine hourly information of residential demand response potential from historical electricity consumption data, which can reflect the distribution of power load and demand response potential. Comparative analysis is used to validate the validity of typical data selection by two-stage clustering.

Introduction Since the 1950s, per- and polyfluoroalkyl substances (PFAS) have been widely used in a variety of industrial and household fields owing to their excellent surface activity, thermal and chemical [...], Background: Oral ingestion, inhalation, and skin contact are important exposure routes for humans to uptake per- and polyfluoroalkyl substances (PFAS). However, nasal and dermal exposure to PFAS remains unclear, and accurately predicting internal body burden of PFAS in humans via multiple exposure pathways is urgently required. Objectives: We aimed to develop multiple physiologically based toxicokinetic (PBTK) models to unveil the route- specific pharmacokinetics and bioavailability of PFAS via respective oral, nasal, and dermal exposure pathways using a mouse model and sought to predict the internal concentrations in various tissues through multiple exposure routes and extrapolate it to humans. Methods: Mice were administered the mixed solution of perfluorohexane sulfonate, perfluorooctane sulfonate, and perfluorooctanoic acid through oral, nasal, and dermal exposure separately or jointly. The time-dependent concentrations of PFAS in plasma and tissues were determined to calibrate and validate the individual and combined PBTK models, which were applied in single- and repeated-dose scenarios. Results: The developed route-specific PBTK models successfully simulated the tissue concentrations of PFAS in mice following single or joint exposure routes as well as long-term repeated dose scenarios. The time to peak concentration of PFAS in plasma via dermal exposure was much longer (34.1-83.0 h) than that via nasal exposure (0.960 h). The bioavailability of PFAS via oral exposure was the highest (73.2%-98.0%), followed by nasal (33.9%-66.8%) and dermal exposure (4.59%-7.80%). This model was extrapolated to predict internal levels in human under real environment. Discussion: Based on these data, we predict the following: PFAS were absorbed quickly via nasal exposure, whereas a distinct hysteresis effect was observed for dermal exposure. Almost all the PFAS to which mice were exposed via gastrointestinal route were absorbed into plasma, which exhibited the highest bioavailability. Exhalation clearance greatly depressed the bioavailability of PFAS via nasal exposure, whereas the lowest bioavailability in dermal exposure was because of the interception of PFAS within the skin layers. https://doi.org/10.1289/EHP11969

During performing multiple tasks of a redundant manipulator, the obstacles affect the sequential order of task areas and the joint trajectories. The end-effector is constrained to visit multiple task areas with an optimal anti-collision path, while the joints are required to move smoothly and avoid predefined obstacles. A special encoding genetic algorithm (SEGA) is proposed for multitask-based anti-collision trajectory planning. Firstly, the spatial occupancy relationship between obstacles and manipulator is developed utilizing the theory of spherical enclosing box and spatial superposition. The obstacles are detected according to the relative position relationship between linear segments and spheres. Secondly, each joint trajectory between adjacent task areas is depicted with a sixth-degree polynomial. Additionally, each joint trajectory is improved via optimizing the unknown six-order coefficient. By searching for optimal sequential order of task areas, optimal collision detection results, and optimal joint trajectories, the multitask-based anti-collision trajectory planning problem is transformed into a parameter optimization problem. In SEGA, the cost function consists of two parts, including the end-effector path length and the variation of joint angles. Moreover, each chromosome consists of three categories of genes, including the sequential order of task areas, the sequential order of joint configurations corresponding to task areas, and the unknown coefficients for anti-collision joint trajectories. Finally, numerical simulations are carried out to verify the proposed method. [ABSTRACT FROM AUTHOR]

Object: Microwave ablation has been widely used in tumor treatment, and the antenna is a critical component of microwave ablation. We aimed to evaluate a single-slot antenna to generate a small volume ablation zone (0. 5 ∼ 4 cm 3) in adrenal tissue. Methods: A three-dimensional numerical model of the adrenal tissue was built and solved by the Finite Element Method. In the simulation model, the slot antenna was placed between the adrenal gland and fat, and the microwave ablation power and time were adjusted to obtain the target ablation zone. In ex vivo experiments, the length and width of the ablation zone were measured, and the significance of ablation parameters on it was determined using a multi-factorial analysis of variance method. The temperature versus time curves at 3 mm and 7 mm from the antenna were plotted to validate the simulation. Results: The simulation results showed that the combination of microwave ablation parameter settings 30 W/300 s, 40 W/180 s, and 40 W/300 s could create ablation zones in the adrenal tissue volumes of 1. 4 , 1. 1 7 and 3. 2 8 cm 3 , respectively, with minimal damage (less than 0. 1 8 cm 3) to the surrounding fat tissue. Both power and heating time significantly affected the length and width of the ablation zone. The temperature rise curves obtained in the simulation and ex vivo experiments were in good agreement. Conclusion: This work shows that utilizing a slot antenna can produce a small volume ablation zone in adrenal tissue for microwave ablation of benign adrenal adenomas. [ABSTRACT FROM AUTHOR]

Background: Alisol A can ameliorate glucose metabolism disorders, however, there is no data regarding its role in diabetic nephropathy (DN). The present work evaluates the role of Alisol A in DN and the underlying mechanism. Methods: RNA expression of circ_0001831, miR‐346, and lin‐28 homolog B (LIN28B) was detected by qRT‐PCR. Cell viability and proliferation were investigated by MTT assay and EdU assay, respectively. The inflammatory cytokines were examined by ELISAs. Oxidative stress was evaluated by the commercial kits. Protein expression was detected by western blotting. The interactions among circ_0001831, miR‐346, and LIN28B were identified by dual‐luciferase reporter assay and RIP assay. DN mouse model assay was used to analyse the effect of Alisol A on renal injury of diabetic mice. Results: HG treatment promoted HRMC proliferation, fibrosis, inflammation, and oxidative stress; however, these effects were reversed after Alisol A treatment. Alisol A treatment ameliorated STZ‐induced renal injury of diabetic mice. Additionally, circ_0001831 or LIN28B overexpression or miR‐346 downregulation relieved Alisol A‐induced effects under HG conditions. Mechanistically, circ_0001831 acted as a miR‐346 sponge, and LIN28B was identified as a target gene of miR‐346. Further, the regulation of circ_0001831 in HG‐induced HRMC dysfunction involved LIN28B. Conclusion: Alisol A ameliorated HG‐induced HRMC fibrosis, inflammation, and oxidative stress and STZ‐induced renal injury of diabetic mice by regulating the circ_0001831/miR‐346/LIN28B pathway. [ABSTRACT FROM AUTHOR]

Baicalin (BCL) has been found to have neuroprotective effects in ischemic stroke (IS), but its underlying molecular mechanisms are unknown. SK‐N‐SH cells were treated with BCL and then induced by oxygen–glucose deprivation/reoxygenation (OGD/R). Cell proliferation, apoptosis, inflammation, and ferroptosis were detected. Protein levels were examined by western blot. The expression levels of microRNA (miR)‐556‐3p and ACSL4 were tested via quantitative real‐time PCR. MiR‐556‐3p and Acyl‐CoA synthetase long‐chain family member 4 (ACSL4) interaction was confirmed via dual‐luciferase reporter assay and RNA pull‐down assay. Middle cerebral artery occlusion (MCAO) mice model was constructed to assess the role of BCL on brain injury in vivo. Our study showed that BCL treatment alleviated OGD/R‐induced SK‐N‐SH cell apoptosis, inflammation and ferroptosis. MiR‐556‐3p was decreased in OGD/R‐induced SK‐N‐SH cells, and BCL treatment enhanced its expression. MiR‐556‐3p could target ACSL4, and its overexpression relieved OGD/R‐induced SK‐N‐SH cell injury by targeting ACSL4. Besides, miR‐556‐3p inhibitor or ACSL4 overexpression reversed the inhibitory effect of BCL on OGD/R‐induced SK‐N‐SH cell injury. In vivo, BCL alleviated brain injury in MCAO mice through miR‐556‐3p/ACSL4 axis. In conclusion, BCL alleviated OGD/R‐induced SK‐N‐SH cell injury and relieved brain injury in MCAO mice by regulating miR‐556‐3p/ACSL4 axis. [ABSTRACT FROM AUTHOR]

Local stiffness and performances of a beam structure will be changed by a crack,which causes changes in mode parameters. Focused on this problem,a simply supported beam is studied based on finite element method. A finite element model of the beam with a vertical embedded crack is presented. Effects of crack length and location on natural frequencies and mode shapes are investigated. Relationships between curvatures of mode shapes and crack length are discussed,as well as those between curvature and crack location. Numerical results show that natural frequencies decrease with crack length,and differences of mode shapes between normal and abnormal beam increase with crack length. Local stiffness of the beam around crack location is changed by the presence of crack,whose area increases with crack length. Curvature of mode shape can be used to detect location of a vertical embedded crack in a simply supported beam.

On the basis of considering the influence of the interface between the bearing outer ring and bearing pedestal,the study and analysis on the relations among the different materials bearing pedestal and rolling element bearing inner ring,outer ring and the vibration characteristic of bearing pedestal are carried out.The analysis results show that the influence of the material characteristic on vibration response of the bearing inner ring,outer ring and bearing pedestal is large,the greater the difference of the elasticity modulus between the bearing and the bearing outer ring,the greater the vibration amplitude of bearing inner ring,outer ring and bearing pedestal. The influence of bearing pedestal material characteristic on the bearing outer ring and bearing pedestal vibration characteristic is larger than the bearing inner ring. The vibration amplitude of the bearing system can be effectively controlled by using appropriate bearing pedestal material.