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Addressing the issues of the sand cat swarm optimization algorithm (SCSO), such as its weak global search ability and tendency to fall into local optima, this paper proposes an improved strategy called the multi-strategy integrated sand cat swarm optimization algorithm (MSCSO). The MSCSO algorithm improves upon the SCSO in several ways. Firstly, it employs the good point set strategy instead of a random strategy for population initialization, effectively enhancing the uniformity and diversity of the population distribution. Secondly, a nonlinear adjustment strategy is introduced to dynamically adjust the search range of the sand cats during the exploration and exploitation phases, significantly increasing the likelihood of finding more high-quality solutions. Lastly, the algorithm integrates the early warning mechanism of the sparrow search algorithm, enabling the sand cats to escape from their original positions and rapidly move towards the optimal solution, thus avoiding local optima. Using 29 benchmark functions of 30, 50, and 100 dimensions from CEC 2017 as experimental subjects, this paper further evaluates the MSCSO algorithm through Wilcoxon rank-sum tests and Friedman's test, verifying its global solid search ability and convergence performance. In practical engineering problems such as reducer and welded beam design, MSCSO also demonstrates superior performance compared to five other intelligent algorithms, showing a remarkable ability to approach the optimal solutions for these engineering problems. [ABSTRACT FROM AUTHOR]

As a complex movement, Tai Chi (TC) could be challenging for knee control, and the compensatory changes in TC biomechanics of knee pain patients are unknown. The Brush Knee and Twist Step (BKTS) is a typical TC movement that involves basic leg motion repeated in the whole TC. This pilot study examined electromyography and retro-reflective marker trajectory data to investigate neuromuscular control strategies of the lower extremity during BKTS in TC practitioners with and without knee pain. Twelve experienced TC practitioners with (n = 6) and without knee pain (n = 6) participated. Our results revealed that knee pain practitioners presented muscle imbalance in the vastus medialis-vastus lateralis and vastus lateralis-biceps femoris, and poor alignment of the knee with the toes in TC lunge. Additionally, they adaptively developed rigid coordination strategies, showing higher levels of lower limb muscle co-contraction and activity compared to controls. Training programs for TC practitioners with knee pain should be designed to modify both abnormal muscle synergy patterns and incorrect lunge during TC, which may improve exercise safety. [ABSTRACT FROM AUTHOR]

Objective SIRT1, an NAD+-dependent deacetylase, is upregulated in CD4+ T cells from SLE patients and MRL/lpr lupus-like mice. This study aimed to explore the role of SIRT1 in follicular helper T (Tfh) cell expansion and its potential value as a therapeutic target for SLE. Methods Frequencies of CD4+CXCR5+PD-1+ Tfh cells in peripheral blood from SLE patients and their expression of SIRT1 and B cell lymphoma 6 (BCL-6) were determined with flow cytometry. Naïve CD4+ T cells were transfected with SIRT1 -expressing lentivirus and small interfering RNA (siRNA) targeting SIRT1 , respectively, and then cultured under Tfh-polarizing conditions to study the impact of SIRT1 on Tfh cell differentiation. This impact was also evaluated in both CD4+ T cells and naïve CD4+ T cells by treatment with SIRT1 inhibitors (EX527 and nicotinamide) in vitro. MRL/lpr mice and pristane-induced lupus mice were treated with continuous daily intake of nicotinamide, and their lupus phenotypes (including skin rash, arthritis, proteinuria and serum anti-dsDNA autoantibodies) were compared with those of controls. Results Expression of SIRT1 was elevated in Tfh cells from SLE patients and was positively correlated with Tfh cell frequencies. SIRT1 expression gradually increased during Tfh cell differentiation. Overexpression of SIRT1 by lentiviral vectors significantly promoted Tfh cell differentiation/proliferation. Reciprocally, suppressing expression of SIRT1 by siRNA and inhibiting SIRT1 activity by EX-527 or nicotinamide hindered Tfh cell expansion. Continuous daily intake of nicotinamide alleviated lupus-like phenotypes and decreased serum CXCL13 in the two mouse models. Conclusion SIRT1 overexpression contributed to the expansion of Tfh cells in SLE and may serve as a potential target for treatment. [ABSTRACT FROM AUTHOR]

Anchoring noble metals to non-noble metals oxide to create single-atom catalysts (SACs) was an appealing approach to improve atomic efficiency and catalyst activity with simultaneous reduction of cost. However, knowledge of how single-atom anchors at unique loading positions and varying numbers of coordination atoms behavior in oxygen evolution reaction (OER) was still inadequate. Herein, the Ir was chosen to anchor at three-fold face center cubic (FCC) hollow sites, three-fold hexagonal close packed (HCP) hollow sites, and Oxygen Vacancy (OV) sites on Co3O4 (111) surface with different coordination environments by first-principles study of OER. The results displayed that the overpotential (η) of threefold FCC hollow sites with four coordination oxygens (FCC-4O) was 0.35 V, which was the lowest overpotential among our catalysts. The d-band center and Bader charge results demonstrated the coordination oxygen could change Ir electron structure, specifically FCC-4O, making the adsorption between the carrier and the intermediate more moderate for reducing the energy barrier of the potential-determining step. When Ir possesses five coordination oxygens, the HCP sites spontaneously transformed into the FCC sites, showing it was an unstable state. In addition, band gap studies indicated that the OV sites catalysts had a reduced band gap and stronger electron transport ability, notably for the Ir with four-coordination hydroxyl group (OV-4OH), which led to high OER performance (η = 0.46 V). Finally, the solvation effect and kinetic stability were tested, it could be found that both FCC-4O and OV-4OH showed good OER performance, especially FCC has good stability and may be more possible in experimental conditions. The figure described volcano diagram of our catalysts and the illustration of FCC sites, HCP sites, and OV sites. FCC-4O had the best OER performance among our catalysts with η = 0.35 V. [ABSTRACT FROM AUTHOR]

Demand Response (DR) is an important component for the establishment of smart electricity grids. It can decrease the system peaks through load shedding or shifting and optimize the utilization of the existing grid assets, which delays the need for costly upgrades. DR can also enable the integration of intermittent and distributed energy resources (DER) into the existing electricity grid. Fast DR from aggregated flexible loads can provide ancillary services (AS) to absorb grid disruptions and may replace the expensive fast-ramping reserve generation units. This study presents a methodology for load aggregation based on the prioritization of loads according to their flexibility. Different flexible load types are categorized as Thermostatically Controlled Loads (TCL), Urgent Non-TCL, Non-urgent Non-TCL, and Battery-based Loads. Models based on their physical behaviour are developed and simulations performed to apply the proposed aggregation and control algorithm. Results show that the loads during peak hours can be shed off without rebound demand spikes after the DR event commonly seen in other types of DR programs. The algorithm also automatically adjusts the power demand according to the output of the distributed renewable generation, mitigating disruptions due to variations of the DER output. Additionally, the algorithm is able to adjust the load demand dynamically according to the fluctuations of electricity price.

This paper presents a novel demand response estimation framework for residential and commercial buildings using a combination of EnergyPlus and two-state models for thermostatically controlled loads. Specifically, EnergyPlus models for commercial and multi-dwelling residential units are applied to construct exhaustive datasets (i.e., with more than 300M data points) that capture the detailed load response and complex thermodynamics of several building types. Subsequently, regression models are fit to each dataset to predict DR potential based on key inputs, including hour of day, set point change and outside air temperature. For single residential units, and residential thermostatically controlled loads (i.e. water heaters and refrigerators) a two-state model from the literature is applied. The proposed framework is then validated for commercial buildings through a comparison with a dataset composed of 11 buildings during 12 demand response events. In addition, the use of the proposed simplified DR estimation framework is presented in terms of two cases (1) peak load shed prediction in an individual building and (2) aggregated DR up/down capacity from a large-scale group of different buildings.

Receptor-like kinases (RLKs) are important for plant growth, development and defense responses. The S-receptor protein kinases (SRKs), which represent an RLK subfamily, control the self- incompatibility among Brassica species. However, little information is available regarding SRK functions in rice. We identified a gene OsSRK1 encoding an atypical SRK. The transcript of OsSRK1 was induced by abscisic acid (ABA), salt and polyethylene glycol. OsSRK1 localized to the plasma membrane and cytoplasm. Leaf width was increased in OsSRK1-overexpression (OsSRK1-OX) transgenic rice plants, likely because of an increase in cell number per leaf. Furthermore, the expression levels of OsCYCA3-1 and OsCYCD2-1, which encode positive regulators of cell division, were up-regulated in leaf primordium of OsSRK1-OX rice plants relative to those in wild type. Meanwhile, the expression level of OsKRP1, which encodes cell cycle inhibitor, was down-regulated in the OsSRK1-OX plants. Therefore, it is deduced that OsSRK1 regulates leaf width by promoting cell division in the leaf primordium. Additionally, OsSRK1-OX plants exhibited enhanced ABA sensitivity and salt tolerance compared with wild type. These results suggest that OsSRK1 plays important roles in leaf development and salt responses in rice. Keywords: rice, S-receptor-like protein kinase, OsSRK1, salt tolerance, leaf width, cell division