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We report the results of time series analysis of blazar PKS 1440-389, observed by the Transiting Exoplanet Survey Satellite (TESS) in two sectors. We find that the source has a quasi-periodic oscillation (QPO) of about 3.1 days for sector 11 and around 3.7 days for sector 38 in the optical band. We use two methods to assess the QPO and its confidence level: Lomb–Scargle periodogram and weighted wavelet Z-transforms. We explore various potential explanations for these rapid quasi-periodic variations and propose that their source most likely resides within the innermost region of the accretion disk. Within this framework, we estimate the mass of the central black hole of this blazar. We obtain black hole masses of 6.65 × 108 M ⊙ (Schwarzschild black hole) and 4.22 × 109 M ⊙ (maximally rotating Kerr black hole), with a main period of 3.7 days. Finally, we utilize the kink instability model to explain the QPO. [ABSTRACT FROM AUTHOR]

The Hydroinformatics Modeling System (HMS) was used to simulate rainfall-runoff experiments to investigate the impact of different slopes and rainfall intensities for traditional and low-impact development (LID) surface conditions. HMS solves the depth-averaged 2D shallow water equations with robust numerical methods. Most importantly, depth-dependent roughness and depth-dependent infiltration methods are implemented and allow the model to simulate a bunch of scenarios. Calibration and validation results are evaluated based on the criteria of the Nash-Sutcliffe Efficiency (NSE) and Standard Deviation Ratio (SDR). Both, the calibration and validation cases achieve very good agreements between computations and measurements with NSE all higher or equal than 0.97 and SDR all smaller or equal 0.17. The results demonstrate the superiority of the depth-dependent infiltration method when compared to a constant infiltration and the necessity of the depth-dependent roughness approach for accuracy and stability reasons. The methods implemented here might also improve other shallow water models. [ABSTRACT FROM AUTHOR]

Simple Summary: Patients with high expression of CXCL8 are not sensitive to immune checkpoint inhibitors (ICIs) treatment, but the mechanism is unclear. LSECtin is the immune checkpoint ligand of LAG3, and is considered as an important factor of ICIs resistance. This study confirmed the role of CXCL8 and LSECtin in immune microenvironment modulation of colon cancer. The expression of CXCL8 is positively correlated with more than 40 immune checkpoints. CXCL8 could up-regulate LSECtin through AKT signal and promoted the proliferation and invasion ability of colon cancer. These results may be important reasons for the primary drug resistance of ICIs in colon cancer. Background: The role of CXCL8 and LSECtin in colon cancer liver metastasis and immune checkpoint inhibitors (ICIs) treatment effect were widely recognized. However, the regulatory role of CXCL8 on LSECtin is still unclear. Methods: The expression of CXCL8 or LSECtin was analyzed by TCGA database, and verified by GES110225 and clinical samples. The relationship between the expression of CXCL8 or LSECtin and immune cells infiltration, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, Gene Ontology (GO) items, stromal score, Estimation of STromal and Immune cells in MAlignant Tumours (ESTIMAT) immune score, tumor mutation burden (TMB), mismatch repair gene and immune checkpoints expression were analyzed by Spearman. The effects of CXCL8 on LSECtin expression, proliferation, and invasion ability were clarified by recombinant CXCL8 or CXCL8 interfering RNA. Results: In colon cancer, the expression of CXCL8 was higher, but LSECtin was lower than that in normal mucosa. The expression of CXCL8 or LSECtin was significantly positively correlated with immune cells infiltration, stromal score, ESTIMATE immune score, TMB, and immune checkpoints expression. The expression of LSECtin was closely related to the cytokine-cytokine receptor interaction pathway and response of chemokine function, such as CXCL8/CXCR1/2 pathway. There was a significant positive correlation between the expression of CXCL8 and LSECtin in colon cancer. CXCL8 up-regulated LSECtin through AKT signal and promoted the proliferation and invasion ability of colon cancer. Conclusions: CXCL8 up-regulated LSECtin by activating AKT signal and correlated with the immune microenvironment modulation in colon cancer. [ABSTRACT FROM AUTHOR]

Background and objective: Stroke is a major contributor to the global burden of disease. Although numerous modifiable risk factors (RF) for stroke have been identified, some remain unexplained. Increasing studies have investigated stroke risk in arthritis, but their results are inconsistent. We aimed to synthesize, quantify, and compare the risk of stroke for the major types of arthritis in cohort studies by using a systematic review and meta-analysis approach. Methods: We searched Chinese and English databases to identify relevant studies from inception to April 30, 2020. Only studies adjusting at least for age and sex were included. We calculated pooled effect estimates for relative risk (RR) and 95% confidence interval (CI) and identified potential sources of heterogeneity and publication bias. Results: A total of 1,348 articles were retrieved, and after an preliminary screening of titles and abstracts, 69 were reviewed for full text, and finally, 32 met the criteria for meta-analysis. Stroke risk in arthritis was significantly increased in studies adjusting for age and sex (RR = 1.36, 95% CI: 1.27–1.46) and for at least one traditional risk factor (RR = 1.40, 95% CI: 1.28–1.54). The results of studies stratified by stroke subtype were consistent with the main finding (ischemic stroke: RR = 1.53, 95% CI: 1.32–1.78; hemorrhagic stroke: RR = 1.45, 95% CI: 1.15–1.84). In subgroup analysis by arthritis type, stroke risk was significantly increased in rheumatoid arthritis (RR = 1.38, 95% CI: 1.29–1.48), ankylosing spondylitis (RR = 1.49, 95% CI: 1.25–1.77), psoriatic arthritis (RR = 1.33, 95% CI: 1.22–1.45), and gout (RR = 1.40, 95% CI: 1.13–1.73) but not osteoarthritis (RR = 1.03, 95% CI: 0.91–1.16). Age and sex subgroup analyses indicated that stroke risk was similar by sex (women: RR = 1.47, 95% CI: 1.31–1.66; men: RR = 1.44, 95% CI: 1.28–1.61); risk was higher with younger age (<45 years) (RR = 1.46, 95% CI: 1.17–1.82) than older age (≥65 years) (RR = 1.17, 95% CI: 1.08–1.26). Conclusions: Stroke risk was increased in multiple arthritis and similar between ischemic and hemorrhagic stroke. Young patients with arthritis had the highest risk. [ABSTRACT FROM AUTHOR]

Testis‐specific protein Y‐encoded 1 (TSPY1), a Y chromosome‐linked oncogene, is frequently activated in prostate cancers (PCa) and its expression is correlated with the poor prognosis of PCa. However, the cause of the ectopic transcription of TSPY1 in PCa remains unclear. Here, we observed that the methylation status in the CpG islands (CGI) of the TSPY1 promoter was negatively correlated with its expression level in different human samples. The acetyl‐histone H4 and trimethylated histone H3‐lysine 4, two post–translational modifications of histones occupying the TSPY1 promoter, facilitated the TSPY1 expression in PCa cells. In addition, we found that androgen accelerated the TSPY1 transcription on the condition of hypomethylated of TSPY1‐CGI and promoted PCa cell proliferation. Moreover, the binding of androgen receptor (AR) to the TSPY1 promoter, enhancing TSPY1 transcription, was detected in PCa cells. Taken together, our findings identified the regulation of DNA methylation, acting as a primary mechanism, on TSPY1 expression in PCa, and revealed that TSPY1 is an androgen‐AR axis‐regulated oncogene, suggesting a novel and potential target for PCa therapy. [ABSTRACT FROM AUTHOR]

Background: Numerous studies have been performed to investigate the association between the primary AZFc duplication and male infertility risk; however, the sample sizes have been small and the results have been controversial. A meta‐analysis was performed to assess these associations. Methods: A systematic search was conducted to identify all relevant studies from the PubMed, Web of Science, Medline, CNKI, and Wanfang databases up to October 22, 2019. The odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to assess the strength of associations. All of the statistical analyses were conducted by using RevMan 5.3. Results: Eleven studies were identified that involved 3140 infertile men and 2280 fertile men. Overall, there was a statistically significant association between the primary AZFc duplication and male infertility (OR = 1.66, 95% CI = 1.29‐2.14, P <.0001). In the subgroup analysis by ethnic group, a statistically significant association between the primary AZFc duplication and male infertility was observed in Asian men (OR = 2.26, 95% CI = 1.64‐3.12, P <.00001), but not in European men (OR = 0.90, 95% CI = 0.59‐1.38, P =.64). For subtypes of the primary AZFc duplication, a statistically significant association was observed between the gr/gr duplication‐only (OR = 2.71, 95% CI = 1.38‐5.32, P =.004) and infertility in Asian men. Asian men with the primary AZFc duplication resulting in more than four DAZ genes were found to be at an increased risk for infertility (OR = 2.70, 95% CI = 1.49‐4.89, P =.001). Conclusion: Our meta‐analysis provides an unprecedented illustration of how the association between the primary AZFc duplication and male infertility may be dependent on ethnicity or geographic location. Furthermore, gr/gr duplication or increased DAZ copy number can be detrimental to spermatogenesis in Asian men. [ABSTRACT FROM AUTHOR]

The article discusses the study of the simple hydrothermal growth method and electronic transport property which is applied to synthesis bismuth oxychloride (BiOCl) single-crystalline microplates. Topics discussed include the observed nonlinear resistivity in the resistivity versus excitation, way to fabricate size-controllable BiOCl samples and the synthesis of BiOCl.

We have developed a supercapacitorelectrode composed of well-alignedCoO nanowire array grown on 3D nickel foam with polypyrrole (PPy)uniformly immobilized onto or firmly anchored to each nanowire surfaceto boost the pseudocapacitive performance. The electrode architecturetakes advantage of the high electrochemical activity from both theCoO and PPy, the high electronic conductivity of PPy, and the shortion diffusion pathway in ordered mesoporous nanowires. These meritstogether with the elegant synergy between CoO and PPy lead to a highspecific capacitance of 2223 F g–1approaching thetheoretical value, good rate capability, and cycling stability (99.8%capacitance retention after 2000 cycles). An aqueous asymmetric supercapacitordevice with a maximum voltage of 1.8 V fabricated by using our hybridarray as the positive electrode and activated carbon film as the negativeelectrode has demonstrated high energy density (∼43.5 Wh kg–1), high power density (∼5500 W kg–1at 11.8 Wh kg–1) and outstanding cycleability(∼20 000 times). After charging for only ∼10s, two such 4 cm2asymmetric supercapacitors connectedin series can efficiently power 5 mm diameter red, yellow, and greenround LED indicators (lasting for 1 h for red LED) and drive a mini130 rotation-motor robustly. [ABSTRACT FROM AUTHOR]

Increasing nitrogen oxides (NO x ) emissions over the fast developing regions have been of great concern due to their critical associations with the aggravated haze and climate change. However, little geographically specific data exists for estimating spatio-temporal trends of NO x emissions. In order to quantify the spatial and temporal variations of NO x emissions, a spatially explicit approach based on the continuous satellite observations of artificial nighttime stable lights (NSLs) from the Defense Meteorological Satellite Program/Operational Linescan System (DMSP/OLS) was developed to estimate NO x emissions from the largest emission source of fossil fuel combustion. The NSL based model was established with three types of data including satellite data of nighttime stable lights, geographical data of administrative boundaries, and provincial energy consumptions in China, where a significant growth of NO x emission has experienced during three policy stages corresponding to the 9 th –11 th Five-Year Plan (FYP, 1995–2010). The estimated national NO x emissions increased by 8.2% per year during the study period, and the total annual NO x emissions in China estimated by the NSL-based model were approximately 4.1%–13.8% higher than the previous estimates. The spatio-temporal variations of NO x emissions at city scale were then evaluated by the Moran's I indices. The global Moran's I indices for measuring spatial agglomerations of China's NO x emission increased by 50.7% during 1995–2010. Although the inland cities have shown larger contribution to the emission growth than the more developed coastal cities since 2005, the High–High clusters of NO x emission located in Beijing-Tianjin-Hebei regions, the Yangtze River Delta, and the Pearl River Delta should still be the major focus of NO x mitigation. Our results indicate that the readily available DMSP/OLS nighttime stable lights based model could be an easily accessible and effective tool for achieving strategic decision making toward NO x reduction. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) transition metal dichalcogenides (TMDs) have a range of unique physics properties and could be used in the development of electronics, photonics, spintronics, and quantum computing devices. The mechanical exfoliation technique of microsize TMD flakes has attracted particular interest due to its simplicity and cost effectiveness. However, for most applications, large-area and high-quality films are preferred. Furthermore, when the thickness of crystalline films is down to the 2D limit (monolayer), exotic properties can be expected due to the quantum confinement and symmetry breaking. In this paper, we have successfully prepared macro-size atomically flat monolayer NbSe 2 films on bilayer graphene terminated surface of 6H-SiC(0001) substrates by a molecular beam epitaxy (MBE) method. The films exhibit an onset superconducting critical transition temperature (T c onset ) above 6 K and the zero resistance superconducting critical transition temperature (T c zero ) up to 2.40 K. Simultaneously, the transport measurements at high magnetic fields and low temperatures reveal that the parallel characteristic field B c// (T = 0) is above 5 times of the paramagnetic limiting field, consistent with Zeeman-protected Ising superconductivity mechanism. Besides, by ultralow temperature electrical transport measurements, the monolayer NbSe 2 film shows the signature of quantum Griffiths singularity (QGS) when approaching the zero-temperature quantum critical point.

Bismuth oxyhalides, such as bismuth oxychlorides (BiOCl), are layered materials with [Bi 2 O 2 ] 2+ layers sandwiched between two sheets of Cl ions. Much work has focused on the potential for bismuth oxyhalides to be a photocatalyst, but their nonlinear optical properties are rarely studied. In this work, the nonlinear refractive index of BiOCl nanosheets has been characterized with Z-scan measurement under 800 nm femtosecond pulsed laser excitation. A shift from saturable absorption to reverse saturable absorption was observed at higher input pump intensities in the experiments. The transition process was analyzed using a phenomenological model based on saturable absorption and two-photon absorption.

Transition metal dichalcogenides (TMDCs), such as tungsten disulfide (WS(2)), are layered materials with strong in-plane bonding and weak out-of-plane interactions enabling exfoliation into two-dimensional layers of single unit cell thickness. Recent advances in nanoscale materials characterization and few layer TMDCs' unique optical properties make them a research hot-spot in nonlinear optics. In this work, the nonlinear refractive index of monolayer WS(2) has been characterized with Z-scan measurement under 800nm femtosecond pulsed laser excitation, and a value of n2 ≃ (8.1 ± 0.41) × 10(-13)m(2)/W is obtained. A shift from saturable absorption to reverse saturable absorption was observed at higher input pump intensities in the experiments. The transition process was analyzed using a phenomenological model based on two photon absorption, and the two photon absorption coefficient was estimated about (3.7±0.28)×10(-6)m/W.