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The lightcurves of asteroids are essential for determining their physical characteristics, including shape, spin, size, and surface composition. However, most asteroids are missing some of these basic physical parameters due to lack of photometric data. Although a few telescopes or surveys are specially designed for photometric lightcurve observations of asteroids, many ground-based and space-based sky surveys for hunting new exoplanets, transient events, etc., should capture numerous small Solar system objects. This will benefit the physical studies of these objects. In order to extract data of these moving objects from time-domain photometric surveys, we have developed a new method using the model tree algorithm in the field of machine learning. A dedicated module is built to automatically identify moving objects in data set and extract their photometric and astrometric data. As the first application of this novel method, we have analysed data in five fields of the Yunnan-Hong Kong wide field photometric (YNHK) survey, from which 538 lightcurves of 211 asteroids are successfully extracted. Meanwhile, we also tested the method based on the data from NASA’s Transiting Exoplanet Survey Satellite, and the result proves the reliability of our method. With derived lightcurves of 13 asteroids from the YNHK survey, we have determined their synodic spin periods, among which the periods of four asteroids are estimated for the first time. In future, we are going to apply this method to search for small objects in the outer part of the Solar system from the Chinese Space Station Telescope survey.

The rational design and controlled synthesis of nanoarchitectures is an important strategy for understanding structure–activity relationships.

Treating patients with esophageal squamous cell carcinoma (ESCC) is challenging due to the high chemoresistance. Growth differentiation factor 15 (GDF15) is crucial in the development of various types of tumors and negatively related to the prognosis of ESCC patients according to our previous research. In this study, the link between GDF15 and chemotherapy resistance in ESCC was further explored. The relationship between GDF15 and the chemotherapy response was investigated through in vitro and in vivo studies. ESCC patients with high levels of GDF15 expression showed an inferior chemotherapeutic response. GDF15 improved the tolerance of ESCC cell lines to low-dose cisplatin by regulating AKT phosphorylation via TGFBR2. Through an in vivo study, we further validated that the anti-GDF15 antibody improved the tumor inhibition effect of cisplatin. Metabolomics showed that GDF15 could alter cellular metabolism and enhance the expression of UGT1A. AKT and TGFBR2 inhibition resulted in the reversal of the GDF15-induced expression of UGT1A, indicating that TGFBR2-AKT pathway-dependent metabolic pathways were involved in the resistance of ESCC cells to cisplatin. The present investigation suggests that a high level of GDF15 expression leads to ESCC chemoresistance and that GDF15 can be targeted during chemotherapy, resulting in beneficial therapeutic outcomes.

Parthenolide (PTL) is a sesquiterpene lactone derived from medicinal plant feverfew (Tanacetum parthenium). Recent studies have demonstrated that it has multiple pharmacological activities, especially in the treatment of various hematological and solid cancers. The superior anticancer activity of PTL suggests that it has the potential to be a first-line drug. However, due to the limited physical and chemical properties, as well as bioavailability, structural modification strategies are strongly recommended to improve the anticancer activity. This review describes representative PTL derivatives obtained by different modification strategies, which are reported to exert antiproliferative activities superior to the parent compound PTL. Furthermore, we also summarize their basic mechanisms on cancer-related signaling pathways, so as to explain the potential and characteristics of PTL and its derivatives in cancer therapy.

Controlling β-amyloid and oxidative stress is indicated to improve Alzheimer’s disease (AD). In this study, we loaded Poly Lactic-co-Glycolic Acid (PLGA) nanoparticles with ligustrazine and coupled them with TED-1 polypeptide, to explore an effective drug for the condition. Tet-1 peptide was coupled to Tetramethylpyrazine (TMP)-PLGA nanoparticles. Glioma cells were then treated with PLGA nanoparticles, TMP, TMP-PLGA nanoparticles, and TMP-PLGA-Tet-1 nanoparticles. Microscope and flow cytometry were then conducted to assess the impact of nanoparticles on cell morphology and toxicity of the nanoparticles. Oxidative stress of the nanoparticles was detected by 2,2-Diphenyl-1-picrylhydrazyl (DPPH) method. TMP-PLGA-Tet-1 nanoparticles were found to have significant ability to scavenge free radicals, also showing significantly increased anti-β-amyloid activity. Finally, Alamar Blue method and 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT) method proved that, the TMP-PLGA-Tet-1 nanoparticles enhanced the efficiency of drug delivery to neurons without toxicity. Moreover, Tet-1-conjugated TMP-PLGA nanoparticles reduced amyloid and alleviated oxidative stress, and may hence be a potential option for treatment of AD. Labeling Tet-1 to TMP-PLGA could therefore improve drug delivery.

Early life stress, including maternal separation, is among one of the main causes of anxiety in adolescents. DNA methyltransferase 3A (Dnmt3a) is a key molecule that regulates DNA methylation and is found to be associated with anxiety-like behavior. It is not clear whether maternal separation affects anxiety levels in mice at different developmental stages or whether Dnmt3a plays a role in this process. Here, by using the open field test to explore the effect of maternal separation on anxiety-like behavior in mice of different ages, it was found that maternal separation could successfully induce anxiety-like behavior in adolescent mice, which continued through adulthood. By using Western blot, we found that the levels of Dnmt3a in the hippocampus and cortex showed different trends in maternal separation mice on postnatal day (P)17. Furthermore, by using immunostaining, we found that the expression levels of Dnmt3a in the cortex and hippocampus were significantly different and decreased to varying degrees with the age of mice, which was the reason for different trends. Our results provide an experimental basis for further development of anxiety/depression treatment programs more suitable for adolescence.

To study the aerodynamic characteristics of the convex structure of a surface-monitoring device on a high-speed train and to evaluate its impact on the aerodynamic performance of the high-speed train, numerical simulation research was conducted on three different layouts of the monitoring device. The computational fluid dynamics (CFD) method was used for the simulation study, and the unsteady compressible NS equation was used as the control equation. Hexagonal grid technology was used to reduce the demand for the grid quantity. The rationality of the grid size and layout was verified through grid independence research. To increase the accuracy of the numerical simulation, the γ-Reθ transition model and improved delayed detached eddy simulation (IDDES) method were coupled for the simulation research. The aerodynamic characteristics of the different operation directions and configurations were compared and analyzed. The research results showed that the windward side of the single pantograph detection device experienced positive pressure, and the sideline and leeward sides experienced negative pressure. Increasing the fillet radius of the sideline could appropriately reduce the aerodynamic resistance. When the speed was about 110 m/s, the drag force coefficient of the detection device was 210~410 N, and the lateral force was small, which means that it had little impact on the overall aerodynamic force of the train. According to the results of the unsteady analysis of the layout with a large space, the resistance during forward travel was greater than that during negative travel. The streamlined upwind surface was conducive to reducing the scope of the leeward separation zone and the amplitude of the pressure fluctuation in the leeward zone, and it thus reduced the resistance. For the running trains, a vortex was formed on their leeward surface. The pressure monitoring results showed that the separated airflow had no dominant frequency or energy peak. The possibility of the following train top and other components experiencing resonance damage is low.

Soil salinity is one of the most serious problems for achieving better crop growth and yield. The study was conducted to isolate, characterize and screen salt tolerant microbes from spinach grown in saline soils. The efficient salt tolerant microbes were characterized for beneficial traits such as nitrogen fixation, phosphate solubilization, indoleacetic acid (IAA), biofilm production, catalase and antagonistic activities, salt tolerance and optimization of bacterial fermentation. Molecular identification of potential microbes was done by 16S rRNA gene sequencing. The collected soil samples were moderately to strongly saline, alkaline in nature, low in N and P while adequate in K and Ca concentration. A total of 17 salt tolerant bacteria differing in colony and cell morphology were characterized. All isolated rhizobacterial microbes had capability to biosynthesize phytohormone IAA, 14 were able to fix atmospheric N2, 11 microbes solubilized inorganic P, 10 produced biofilm and 15 were positive in catalase activity. The isolated rhizobacteria showed salt tolerance up to 10 % induced salinity, only six microbes tolerated salt concentration of 12.5% however, none of any rhizobacteria remained viable at 15% NaCl amended media plates. The two potential salt tolerant microbes (NIA SP-6 & NIA SP-11) were screened and found for optimum growth curve and fermentation at pH 7.0 after 48 hrs of incubation period. Both potential microbes were identified as Enterobacter cloacae (NIA SP-06) and Bacillus safensis (NIA SP-11). Hence, it can be concluded that isolated salt tolerant rhizobacterial microbes have potential for beneficial traits and have ability for salt tolerance under saline conditions.

Objectives To assess the independent causal effect of body mass index (BMI) and 25-hydroxy-vitamin D (25(OH)D) level on basal cell carcinoma(BCC), we performed univariable and multivariable two-sample Mendelian randomization (MR) analysis. Methods We used overlapping genome-wide significant single nucleotide polymorphisms(SNPs) for BMI and 25(OH)D as instrumental variables and selected effective SNPs to applied a series of MR methods including inverse variance weighted (IVW),MR Egger,and Weighted median. After that, we employed sensitivity analysis to make sure the results were reliable and robust. Results In the univariable two-sample MR analysis, higher BMI was related to lower risk for BCC (Odds ratio(OR)=0.90; 95%confidence interval (CI),[0.81,0.99]; p = 0.02). In the multivariable MR, the causal effect of BMI on BCC after adjusting for 25(OH)D level still remained(OR=0.88; 95% CI,[−0.22; −0.03], p-value=0.008).However,our results suggest that 25(OH)D level was not associated with BCC(OR=1.02; 95%CI,[0.94,1.09],p-value=0.67). Conclusion Similar to the conclusions of previous observational studies, the MR results suggest that BMI is an independent protective factor for BCC. While, vitamin D levels may not be causally associated with the risk of basal cell carcinoma and increasing vitamin D supplementation is unlikely to reduce the risk.

The practical applications of perovskite solar cells (PSCs) are limited by the further improvement of their stability and performance. Interface engineering is a promising strategy to solve these pain points. Herein, we design (R)-(-)-1-cyclohexylethylamine iodide (R-CEAI), composed of positively charged hydrophobic R-CEA