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The screened In2STe/GeH vdW heterostructure is a direct type-II semiconductor with 1.25 eV band gap, directionally anisotropic carrier mobility, and good stability. Strain engineering can enhance the theoretical PCE to reach 19.71%.

The pyrolysis temperature strongly affects the properties of the peanut shell biochar, and influences its adsorption behavior and mechanisms for contaminant removal in aqueous solutions. In this study, peanut shells were pyrolyzed at 400 °C and 700 °C to prepare two biochars (PSBC400 and PSBC700), which were then characterized using scanning electron microscopy/X-ray energy spectrum analysis, Brunauer–Emmett–Teller, elemental analysis, X-ray fluorescence, X-ray diffraction, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The adsorption behavior of typical tetracycline (TC) onto the biochars was investigated, and the potential adsorption mechanisms explored. The results show that compared with PSBC400, PSBC700 has a larger specific surface area and pore volume and contains higher levels of carbon and ash, but shows lower O, N, and H content. The hydrophilicity and polarity of PSBC700 is lower, but its aromaticity is higher. Furthermore, the mineral content of PSBC400 is higher than for PSBC700. The functional groups differ between PSBC400 and PSBC700, especially those containing C and O. The Elovich and two-compartment adsorption kinetic models are a good fit to the TC adsorption processes on both biochars, but the Langmuir adsorption isotherm model provides better results. The theoretical maximum adsorption capacities of TC onto PSBC700 and PSBC400 are 33.4346 mg·g−1 and 26.4185 mg·g−1, respectively. The main adsorption mechanisms of TC onto PSBC400 are hydrogen bonding and complexation, and are closely related to the functional groups and minerals found in PSBC400. In contrast, the main adsorption mechanisms of TC onto PSBC700 are pore filling and the π–π interaction, and are mainly determined by the surface area and graphited carbon structure of PSBC700. In summary, effective biochar can be manufactured from peanut shell biomass and can be used to remove TC from aqueous solutions.

Background Symptomatic intracranial artery stenosis (ICAS) is a significant worldwide economic and great threat to public health. Currently, little is known about the accurate status of the efficient and tolerable dose of dual antiplatelet therapy (DAPT) as the mainstay treatment for ICAS. The aim of this study is to evaluate the efficacy and safety of aspirin plus clopidogrel in small doses for the treatment of symptomatic ICAS in the elderly. Methods This research included 142 older adults with symptomatic ICAS who were enrolled between April 2013 and April 2018. They were split into two groups: 73 patients in the lower dose group who received 75 mg of aspirin daily and 50 mg of clopidogrel daily, and 69 patients in the usual group who received 100 mg of aspirin daily and 75 mg of clopidogrel daily. Results Ages of 142 patients ranged from 60 to 81, with a mean of 70.9 ± 6.4. 58 participants were with IS and 84 were with TIA. A total of 132 patients were followed up. The low-dose group had a lower recurrence risk of ischemic stroke (IS) or transient ischaemic attack (TIA) than the conventional group at 1-year and 2-year follow-up, as well as a reduced frequency of adverse events and gastrointestinal injury (P P > 0.05). Conclusion The efficacy and safety of low-dose aspirin combined with clopidogrel were significantly better than those of ordinary dose within 24 months in elderly patients with symptomatic ICAS. However, the small size of this study limits the validity of the results.

Epithelial ovarian cancer and breast cancer are common gynecological malignancies with high mortality rates. Isoflavones are phytoestrogens that are ubiquitous in food and Chinese herbs. Although many epidemiological studies have shown that ingestion of isoflavones could decrease the risk of ovarian and breast cancer, their cellular functions and underlying mechanisms remain unclear. This study used isoflavones to treat the breast and ovarian cancer cell lines SKOV-3 and MCF-7, which have high estrogen levels. Cell number and viability were measured using cell counting and MTS assays, respectively. Real-time quantitative PCR and western blotting were used to investigate the expression levels of key apoptotic factors. The results showed that isoflavones inhibited the proliferation and viability of SKOV-3 and MCF-7 cells under high estrogen levels. The expression levels of p62, LC3B, Caspase3, Bax, and Cyt c were significantly increased, whereas the expression levels of Bcl-2 were significantly decreased when treated with isoflavone. These results suggest that isoflavones can inhibit autophagy and induce apoptosis in ovarian and breast cancer cells at high estrogen levels. These findings provide a new theoretical basis for the treatment of malignant gynecological tumors.

Cooperative microgrids (CMGs) can effectively solve the energy interaction between microgrids (MGs) while increasing the penetration rate of renewable energy systems (RESs) and reducing the interaction frequency with the grid. However, the uncertainty of RESs will bring new challenges to the energy management and economic dispatch of CMGs, especially in increasing the number of MGs connected to the grid. Taking into account this uncertainty, it is extremely unlikely that the forecast uncertainty information will be at the worst values in every period, and this forecast uncertainty information is near the expected values in most cases. Therefore, a two-stage robust optimal model under expected scenarios for CMGs is proposed in this study to improve the conservatism of traditional models and minimise the daily cost. In this model, the first-stage decision results (FDRs) are determined by minimising the daily cost of CMGs under the expected scenarios. The proposed model is transformed based on two-stage zero-sum game theory and dual theory, a column and constraint generation algorithm is first used to test the robust feasibility of the FDR, and the second-stage decision results can be obtained without changing the FDR. Case studies verify that the proposed model can effectively solve energy transactions between MGs while mitigating the uncertainty disturbances in the operation of CMGs.

Background: Epithelial ovarian cancer and breast cancer are common gynecological malignancies with a high mortality rate. Isoflavone is a phytoestrogen that is ubiquitous in food and Chinese herbs. Although many epidemiological studies have shown that ingestion of isoflavones can reduce the risk of ovarian and breast cancer, its cellular functions and underlying mechanisms remain unclear. Methods: This study used isoflavones to treat SKOV-3 (ovarian cancer) and MCF-7 (breast cancer) cell lines with high estrogen levels. Cell counting and MTS assays were used to detect cell proliferation and viability. Quantitative PCR and western blotting were performed to investigate the expression levels of cell cycle factors. Results: The results showed that isoflavones inhibited cell proliferation and viability in SKOV-3 and MCF-7 cells under high estrogen levels. After isoflavone treatment, PCNA, CDK4, and cyclin D1 expression levels were significantly decreased, but p21 and p27 expression levels were significantly increased. Conclusion: Isoflavones could inhibit cell proliferation within high levels of estrogen in ovarian and breast cancer cells. These findings will provide a new theory for gynecological malignancy therapy.

α-Substituted peroxides have been found in natural products and are widely used as anti-malarial agents. Zn(OTf)2 -catalyzed peroxidation of 1,3,5-triazines has been developed, accessing diversely substituted α-amino tertiary alkylperoxides with high efficiency. Mechanistic investigations and useful synthetic application of the products have also been presented.

Chemokine receptor 2 (CXCR2) is the receptor of glutamic acid–leucine–arginine sequence-contained chemokines CXCs (ELR+ CXCs). In recent years, CXCR2-target treatment strategy has come a long way in cancer therapy. CXCR2 antagonists could block CXCLs/CXCR2 axis, and are widely used in regulating immune cell migration, tumor metastasis, apoptosis and angiogenesis. Herein, two series of new CXCR2 small-molecule inhibitors, including 1,2,4-triazol-3-one derivatives 1–11 and pyridazinone derivatives 12–22 were designed and synthesized based on the proof-to-concept. The pyridazinone derivative 18 exhibited good CXCR2 antagonistic activity (69.4 ± 10.5 %Inh at 10 μM) and demonstrated its significant anticancer metastasis activity in MDA-MB-231 cells and remarkable anti-angiogenesis activity in HUVECs. Furthermore, noteworthy was that 18 exhibited an obvious synergistic effect with Sorafenib in anti-proliferation assay in MDA-MB-231 cells. Moreover, 18 showed a distinct reduction of the phosphorylation levels of both PI3K and AKT proteins in MDA-MB-231 cells, and also affected the expression levels of other PI3K/AKT signaling pathway-associated proteins. The molecular docking studies of 18 with CXCR2 also verified the rationality of our design strategy. All of these results revealed pyridazinone derivative 18 as a promising CXCR2 antagonist for future cancer therapy.

Smart surfaces for micro-conveyance are planar motion devices that transport objects between specific positions. The solutions in this research topic have mainly used analog/continuous actuators with distributed sensors and feedback control schemes to accomplish high precision. Examples of these analog actuators are pneumatic (non-contact) and electrostatic (contact) conveyance systems, but their drawbacks are: complex modeling, control and air feeding logistics for the pneumatic solutions; and pull-in failures and high voltages for the electrostatic solutions. As an alternative, digital electromagnetic actuators offer sensor-less operation, simple control schemes and high precision but require precisely fabricated designs. In this article, we analyze the long-range capability of a digital electromagnetic actuator array prototype. We present the array’s operation principle and electromagnetic model, from which we derive the positives of expanding its active area. We perform experimental tests to demonstrate the long-range capability of the prototype and, based on the model and experimental results, we present and fabricate a modular and scalable design of the array for large active area applications.

In this paper a 5 × 5 micromachined digital electromagnetic actuator array for microdisplacements is presented. Each elementary actuator is composed of a permanent magnet placed in a silicon square cavity. This magnet can be switched between four discrete positions and can be switched by applying current pulses through wires placed below the cavity. A semi-analytical model has been developed to design the actuator. Then, a prototype, composed of a silicon part, has been manufactured using deep reactive ion etching process. An elementary actuator was as firstly experimentally characterized. Then the array was used to realize a conveyance task. The maximum displacement quantum of the conveyed object is 115 µm.

With the increasing penetration of renewable generation such as wind power in modern power systems, there are many new challenges arising in power system operation with respect to reliability and economy. In this work, we study a two-stage data-driven distributionally robust (DR) energy and reserve dispatch problem with uncertain wind power. Different from the general moment-based ambiguity set, we design a new distance-based ambiguity set to describe the uncertain probability distribution of wind power, which can be constructed in a data-driven manner from historical data. Base on this new ambiguity set, the second-stage worst-case expectation of the problem is reformulated to a combination of conditional value-at-risk (CVaR) and an expected cost with respect to a reference distribution. Thus, the proposed two-stage DR model becomes a two-stage stochastic optimization problem which can be readily solved. Case studies are carried out to verify the effectiveness of the proposed method based on the IEEE 6-bus test system and modified IEEE 118-bus test system. Simulation results show the value of data in controlling the conservatism of the problem, and the DR problem converges to the stochastic problem with fixed distribution as the data size goes to infinity.

In this paper we present the characterization of a digital actuator array (DAA), based on a 2×2 matrix of digital electromagnetic actuators, as a conveyor device towards a micro-factory application. A proposed conveyance principle of the DAA was experimentally applicated and validated. The displacement of the conveyed object along one and two dimensions, the speed and the energy consumption reached by this DAA were characterized. Displacements from 38.3 µm up to 1181.9 µm were measured with a maximum speed of 1990.4 µm/s. Energy calculations showed an efficiency up to 282.5 µm/J and the 2 DOF capability of the DAA was experimentally demonstrated.

Microgrids play an important role in modern power systems which can integrate different kinds of distributed energy resources (DERs). To deal with the uncertainty from various factors such as renewable generation, robust energy management for microgrids has become a significant problem. In this work, a novel multistage robust energy management model for grid-connected microgrids is developed which considers the uncertainty of renewable generation and load demand. The multistage energy management problem is complex and computationally difficult. To solve this problem, a robust version of dual dynamic programming method is proposed which includes a forward pass and a backward pass procedure and has a similar framework with the common stochastic dual dynamic programming (SDDP) method. Based on real datasets, a case study is carried out to validate the effectiveness of the proposed model and solution methodology. Numerical results show that the proposed approach can effectively achieve the robust optimal solution, and the comparison with other methods also testifies the advantage of the proposed multistage robust model.

Buckled beam-based bistable actuators are the key for contactless digital actuation. In this paper, the design, fabrication and characterization of bistable buckled beams is presented. A series of structures based on pre-shaped buckled beams of lengths ranging from 2 to 4 mm, a constant width of 5 um and an actuation stroke ranging from 20 to 100 um was fabricated. Experimental data show a significant difference with classical model predictions, mainly because the actuation method results in a displacement which is a combination of several buckling modes. Thus the model commonly used for buckled beams design has then been modified in order to take into account the beam shape effectively fabricated and experimental results. An accurate model was obtained, enabling good prediction of the experimental switching behavior of microfabricated buckled beams.

We developed an efficient method for synthesis of tetrafunctionalized 2-imidazolines using TfOH-catalyzed formal [3+2] cycloaddition of N-tosylaziridine dicarboxylates and nitriles. This is the first report of C–N bond cleavage of N-tosylaziridine dicarboxylates catalyzed by Bronsted acid and the reaction worked well over wide scope of substrates in good to excellent yields under mild conditions. The method has the potential to be applied to pharmaceutical design and synthesis of tetrafunctionalized 2-imidazolines.