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In this study, the fast response of East Asian summer precipitation to COVID-induced aerosol emission reductions is examined using the Community Earth System Model version 2.2 (CESM2.2). The emission reductions decreased aerosol optical depth and cloud cover over northern China in June 2020. The troposphere became warmer, strengthening the land-sea thermal contrast and anomalous southerly winds. The subtropical westerly jet accelerated and shifted southwards, favoring the low-level convergence, upward air motions, and subsequent condensational heating over the Yangtze River Basin (YRB). The feedback of condensational heating in return strengthened the convergence and ascent. The western North Pacific Subtropical High was intensified, which further enhanced the moisture advection and convergence over the YRB. Both the enhanced moisture convergence and ascent increased precipitation over the YRB during June 2020. Furthermore, local and remote emission reductions show different impacts on convection and moisture transport over the YRB. The emission reductions over China caused stronger convective precipitation (1.15 mm/day versus 0.63 mm/day), but weaker larger-scale precipitation (1.17 mm/day versus 2.24 mm/day) than the emission reductions outside China did. In addition to the emission reductions, the sea surface temperature (SST) anomalies in 2020 also play an important role in increasing precipitation over the YRB, contributing about 42.8%. And the relative contribution from SST anomalies even increases under the COVID-induced emission scenario.

High-mobility van der Waals ambipolar semiconductors are promising in logic and reconfigurable circuits, integrated optoelectronic circuits, due to the excellent gate-controlled capability and effectively tunability of major charge carriers by electrostatic field. Controllable growth of high-quality ambipolar semiconductors with high mobility and stability is highly glamorous and indispensable for further research. Here, we demonstrate a straightforward space-confined chemical vapor deposition (CVD) method to synthesize high-quality quasi-one-dimensional (1D) tellurium (Te) nanoribbons (NRs). By introducing H2 into the gas flow, endothermic compound H2Te was generated from the reaction of liquid Te with H2, and consequently decomposed into elemental Te at low temperature. Further, the Te NRs have been utilized for in-situ fabrication of field-effect transistors (FETs) without transferring process. Ambipolar features are achieved using nickel (Ni) as an ohmic contact. More importantly, the mobilities of the Te NR transistor for hole/electron are as high as 1755/28.6 cm2V−1s−1 and 4024/278 cm2V−1s−1 at room temperature and under a temperature below 20 K, respectively. Our findings confirm the novel strategy for synthesizing 1D elemental semiconductors and their applications with ambipolar behaviors. Agency for Science, Technology and Research (A*STAR) National Research Foundation (NRF) Submitted/Accepted version The authors gratefully acknowledge financial support by National Key Research and Development Program of China (2020YFB2008501), the National Natural Science Foundation of China (61974120 and 11904289), Key Research and Development Program of Shaanxi Province (2020ZDLGY04-08, 2020GXLH-Z-027, and 2021JZ-43), the Natural Science Foundation of Shaanxi Province (2023-JC-YB-495 and 2022JQ-659), the Key Program for International Science and Technology Cooperation Projects of Shaanxi Province (2018KWZ-08), the Natural Science Foundation of Ningbo (202003N4003), the Fundamental Research Funds for the Central Universities (3102019PY004, 31020190QD010, and 3102019JC004), the start-up funds from Northwestern Polytechnical University, and open research fund of the State Key Laboratory of Organic Electronics and Information Displays. This work was also supported by National Research Foundation–Competitive Research Program NRF-CRP22-2019-0007 and NRF-CRP21-2018-0007, and supported by A*STAR under its AME IRG Grant (Project No. A2083c0052).

Efficient and accurate state detection of transmission cables is an important means to ensure reliable transmission. Aiming to realize fast and efficient transmission cable state analysis with the help of a binocular vision tool on a loop dismantling robot, this paper proposes a transmission cable state recognition method combining motion control and image segmentation technology. In this method, the fuzzy P I D control method is adopted to ensure that the wire removal robot can realize high-precision and rapid response control and effectively improve the collection quality of the cable image sample set. Meanwhile, aiming to achieve faster and more efficient data acquisition and state analysis, the state analysis model is sunk to the edge side, and the cable state detection and recognition model is constructed based on the fast RCNN model at the edge of the network to realize the in-depth extraction of feature information, enhance the transmission cable state recognition effect of the state detection model, and improve the response analysis speed of the model. The simulation results show that the accuracy of the proposed method is 97.54%, and its calculation time is 1.034 s, which can effectively realize the analysis and research of transmission cable state under complex working conditions.

Applying cohesive soil to wrap fine sand on a subgrade slope is a new type of filling technology in railway subgrade construction. The choices of specific compaction methods and quality evaluation indicators are critical for achieving high compaction quality. In this paper, a series of field rolling tests with different compaction machines was carried out in the experimental section of China Menghua railway. Then, the compaction quality was gauged considering different indexes such as relative density (Dr), degree of compaction (K), coefficient of subgrade reaction (K30) and dynamic modulus of deformation (Evd). It is shown that adopting clayey soil (namely, wrapping soil) to cover a sandy roadbed slope can keep the internal humidity of the subgrade stable. For compaction of the fine sand used in this study, it was better to select a bulldozer to squeeze along the longitudinal and horizontal directions alternately six times, and the lift thickness was set at 35 cm. The results show a linear relationship between Evd and K30 for the sand. The application of Evd as a substitute for K30 in the compaction evaluation of sand subgrade can lead to significant efficiency.

A novel Y2CaHfScAl3O12:Cr3+,Yb3+ NIR phosphor and application demonstration in the fields of information encryption and non-invasive detection.

Insights into Pt and Zn speciation during the formation of PtZn intermetallic nanoparticles and how Pt–Zn nanocatalysts show enhanced catalytic performance in the dehydrogenation of ethane.

The evaluation of energy security offers a standard for policy research and highlights the problems of securing the energy supply. A composite index for analyzing the risk of Southeast Asian nations' oil supply is developed in this study. Indicators used to calculate the index include the import-to-LGE ratio, GPR, market liquidity, gross domestic product, the import-to-consumption ratio, heterogeneity, oil price volatility, US$ volatility, and transportation risk. The index is based on these and other factors. According to the findings, Nepal and Sri Lanka are the most susceptible to oil supply interruptions. This indicates that India is more likely to shift its oil suppliers. At the same time, Maldives, Nepal, and Sri Lanka have the lowest supply risk scores, indicating that they are the most vulnerable to supply disruptions. Reduce the effect of oil supply risk by enacting policies such as the adoption of renewable technologies, nuclear power generation, diversification of exporting supplies, and reducing fossil fuel subsidies.

Thirty-four individual thermohaline sheets are identified at depths of 170–400 m in the Canada Basin of the Arctic Ocean by using the hydrographical data measured with the Ice-Tethered Profilers (ITPs) between August 2005 and October 2009. Each sheet is well determined because the salinity within itself remains very stable and the associated salinity anomaly is markedly smaller than the salinity jump between neighboring sheets. These thermohaline sheets are nested between the Lower Halocline Water (LHW) and Atlantic Water (AW) with lateral coherence of hundreds of kilometers and thickness varying from several to dozens of meters. The physical properties, including temperature, heat flux, and vertical turbulent diffusivity, in the sheet are found to be averagely associated with the AW propagation. Spatially, the thermohaline sheet is in a bowl-shaped distribution, which is deepest in the basin center and gradually becomes shallower toward the periphery. The interaction between the LHW and AW could be demonstrated through the property variances in the sheets. The temperature variances in the upper and lower sheets are correlated with the LHW and AW, respectively, transited at the 15th sheet, whereas the depth variance in the sheet is strongly correlated with the LHW. It is proposed that the sheet spatial distribution is mainly dominated by the Ekman convergence with the Beaufort Gyre, slightly modulated with the AW intrusion. Significance Statement The diffusive convection staircases, composed of consecutive steps containing thick mixed layers and relatively thin interfaces, are prominent between the Lower Halocline Water (LHW) and the Atlantic Water (AW) throughout the Canada Basin. This sheet-like structure is in a bowl shape with lateral coherence over hundreds of kilometers. It is proposed that the distribution of the thermohaline sheet is mainly dominated by the Ekman convergence with Beaufort Gyre, as well as the AW intrusion. The present method of thermohaline-sheet identification would have more implications beyond this work. Since the thermohaline sheet remains mostly stable and coherent on a very large spatial–temporal scale, it might play a similar role as the water mass analysis in numerous applications, e.g., climate change.

A nitrogen-doped fullerene dimer is synthesized and compounded with multi-walled carbon nanotubes (MWCNTs) to construct a low-dimensional and metal-free 0D-1D heterostructure for electrocatalytic water oxidation. The (C

Release of alcohol from quinone propionic esters (QPEs) propelled by visible-light is reported. 1°, 2°, and allylic alcohols could be freed from the corresponding QPEs under radiation from blue LED bulb in the presence of a photocatalyst. Ten examples are listed and the yields are good to excellent. Possible mechanism has been proposed and further applications of quinone propionic acid (QPA) in photochemistry would be expected.

Hemiepiphytic figs killing their host trees is an ecological process unique to the tropics. Yet the benefits and adaptive strategies of their special life history remain poorly understood. We compared leaf phosphorus (P) content data of figs and palms worldwide, and functional traits and substrate P content of hemiepiphytic figs (Ficus tinctoria), their host palm and nonhemiepiphytic conspecifics at different growth stages in a common garden. We found that leaf P content of hemiepiphytic figs and their host palms significantly decreased when they were competing for soil resources, but that of hemiepiphytic figs recovered after host death. P availability in the canopy humus and soil decreased significantly with the growth of hemiepiphytic figs. Functional trait trade-offs of hemiepiphytic figs enabled them to adapt to the P shortage while competing with their hosts. From the common garden to a global scale, the P competition caused by high P demand of figs may be a general phenomenon. Our results suggest that P competition is an important factor causing host death, except for mechanically damaging and shading hosts. Killing hosts benefits hemiepiphytic figs by reducing interspecific P competition and better acquiring P resources in the P-deficient tropics, thereby linking the life history strategy of hemiepiphytic figs to the widespread P shortage in tropical soils.

Nesfatin-1, a newly identified energy-regulating peptide, has been reported to possess antioxidant, anti-inflammatory, and antiapoptotic properties; however, to date, its effect on rheumatoid arthritis (RA) has not been previously explored in detail. We previously showed that activation of acid-sensing ion channel 1a (ASIC1a) by acidosis plays an important role in RA pathogenesis. Therefore, in this study, we evaluated the effects of nesfatin-1 on acidosis-stimulated chondrocyte injury in vitro and in vivo and examined the involvement of ASIC1a and the mechanism underlying the effects of nesfatin-1 on RA. Acid-stimulated articular chondrocytes were used to examine one of the several possible mechanisms underlying RA pathogenesis in vitro. The mRNA expression profile of acid-induced chondrocytes treated or not treated with nesfatin-1 was investigated by RNA sequencing. The effects of nesfatin-1 on oxidative stress, inflammation, and apoptosis in acid-induced chondrocytes were measured. The mechanistic effect of nesfatin-1 on ASIC1a expression and intracellular Ca

Why oxygen ceases the growth of strictly anaerobic bacteria is a longstanding question, yet the answer remains unclear. Studies have confirmed that the dehydratase-fumarase containing an iron-sulfur cluster ([4Fe-4S]) is inactivated upon exposure to oxygen in the intestinal obligate anaerobe, Bacteroides thetaiotaomicron (B. thetaiotaomicron); this blocks fumarate respiration, which is the essential energy-producing pathway in anaerobes. Here, we substituted the [4Fe-4S]-dependent fumarase in B. thetaiotaomicron with an iron-free isozyme from E. coli (Ec-FumC). Results show that Ec-FumC successfully performed the catalytic function of fumarase in B. thetaiotaomicron, as the fum-mutant strain that expressed Ec-FumC exhibited succinate-producing ability under anaerobic growth conditions. Ec-FumC is oxygen-resistant and remains active to produce fumarate upon aeration; however, B. thetaiotaomicron mutant that expressed Ec-FumC did not convert fumarate to succinate during air exposure. Biochemical assays of inverted membrane vesicles from wild-type B. thetaiotaomicron confirmed that the electron flux from NADH to fumarate was less efficient in the presence of air as compared to that without oxygen. Our findings suggest that the anaerobic fumarate respiration might be paralyzed due to electron dissipations upon aeration of the obligate anaerobe.

Apigenin (APN), a flavone found in several plant foods with various biological properties such as anti-obesity, anti-inflammation and other abilities, alleviates atherosclerosis and non-alcoholic fatty liver disease (NAFLD) induced by a high fat diet (HFD) in mice. However, the underlying mechanisms have not been fully understood. In this study, we investigated the role of NLRP3 in anti-atherosclerosis and anti-NAFLD effect of APN in mouse models with NLRP3 deficiency. Atherosclerosis and NAFLD models were established by treatment of low density lipoprotein receptor-deficient (Ldlr−/−) mice and NLRP3−/− Ldlr−/− mice with a HFD diet (20% fat and 0.5% cholesterol) with or without APN. En face lipid accumulation analysis, plasma lipid levels, hepatic lipid accumulation and inflammation were analyzed and quantified. For in vitro experiments, HepG2 cells were stimulated by LPS plus oleic acid (OA) in the absence or presence of APN (50 μM). Lipid accumulation and the effect of APN on the NLRP3/NF-κB signaling pathway were investigated. APN administration partly reversed atherosclerosis and hepatic lipid accumulation, and decreased body weight and plasma lipid levels in Ldlr−/− mice when fed a HFD. Compared with Ldlr−/− mice, NLRP3−/− Ldlr−/− mice showed more severe atherosclerosis and hepatic lipid accumulation. Treating the HepG2 cells with APN reduced lipid accumulation. APN also inhibited activation of the NLRP3/ NF-κB signaling pathway stimulated by OA together with LPS. Our results indicate that APN supplementation prevents atherosclerosis and NAFLD via NLRP3 inhibition in mice, and suggest that APN might be a potential therapeutic agent for the prevention of atherosclerosis and NAFLD.

Anthropogenic heat release (AHR) is the release of heat generated by anthropogenic energy consumption. The global mean flux of AHR is 0.03 W m−2, while AHR is geographically concentrated and fundamentally correlates with economic activity; furthermore, AHR can reach a level sufficient for impacting regional even large-scale climate. In this study, the impacts of AHR on the summer European heatwaves (EHWs) are examined by using the Community Earth System Model version 1 (CESM1). The results show that in Europe, AHR increases the summer mean 2-m temperature by 0.26 °C and the surface minimum and maximum temperatures by 0.14 °C and 0.41 °C, respectively. AHR exacerbates the extreme high temperatures in the summer in Europe, increasing EHW days by 1–2 days in central and eastern Europe in the summer annually from 1992 to 2013. AHR strengthens the surface wind that flows from the ocean to the land in Europe by increasing the land surface temperatures. AHR decreases the lower-troposphere stability (LTS) and reduces the low-cloud amounts in Europe, which leads to more solar shortwave radiation reaching the surface. AHR affects water vapor and the surface energy balance in Europe, which impacts on European summer heatwaves further. AHR acts as a non-negligible factor for summer extreme high temperature in Europe and a potential factor impacting EHW days.

Background Aedes aegypti is a vector that transmits various viral diseases, including dengue and Zika. The radiation-based sterile insect technique (SIT) has a limited effect on mosquito control because of the difficulty in irradiating males without reducing their mating competitiveness. In this study, the insect sex pheromone heptacosane was applied to Ae. aegypti males to investigate whether it could enhance the mating competitiveness of irradiated males. Methods Heptacosane was smeared on the abdomens of Ae. aegypti males that were allowed to mate with untreated virgin females. The insemination rate was used to assess the attractiveness of heptacosane-treated males to females. The pupae were irradiated with different doses of X-rays and γ-rays, and the emergence, survival time, egg number, and hatch rate were detected to find the optimal dose of X-ray and γ-ray radiation. The males irradiated at the optimal dose were smeared with heptacosane, released in different ratios with untreated males, and mated with females. The effect of heptacosane on the mating competitiveness of irradiated mosquitoes was then evaluated by the hatch rate, induced sterility, and mating competitiveness index. Results Applying heptacosane to Ae. aegypti males significantly increased the insemination rate of females by 20%. Pupal radiation did not affect egg number but significantly reduced survival time and hatch rate. The emergence of the pupae was not affected by X-ray radiation but was affected by γ-ray radiation. Pupae exposed to 60 Gy X-rays and 40 Gy γ-rays were selected for subsequent experiments. After 60 Gy X-ray irradiation or 40 Gy γ-ray irradiation, the average hatch rate was less than 0.1%, and the average survival time was more than 15 days. Moreover, at the same release ratio, the hatch rate of the irradiated group perfumed with heptacosane was lower than that of the group without heptacosane. Conversely, the male sterility and male mating competitiveness index were significantly increased due to the use of heptacosane. Conclusions The sex pheromone heptacosane enhanced the interaction between Ae. aegypti males and females. Perfuming males irradiated by X-rays or γ-rays with heptacosane led to a significant increase in mating competitiveness. This study provided a new idea for improving the application effect of SIT. Graphical Abstract

Molecular ferroelectrics with excellent ferroelectric properties and a low processing temperature, a narrow bandgap, and light weightiness have shown great potential in the photovoltaic field. However, two-dimensional (2D) perovskite solar cells with high tunability, excellent photo-physical properties, and superior long-term stability are limited by the poor out-of-plane conductivity from intrinsic multi-quantum well electronic structures. This work uses 2D molecular ferroelectric as the absorbing layer to break the limit of multiple quantum wells. Our 2D ferroelectric solar cells achieve the highest open-circuit voltage (1.29 V) and the best efficiency (3.71%) among the 2D (n = 1) Ruddlesden–Popper perovskite solar cells due to the enhanced out-of-plane charge transport induced by molecular ferroelectrics with a strong saturation polarization, high Curie temperature, and multiaxial characteristics. This work aims to break the inefficient out-of-plane charge transport caused by the limit of multi-quantum well electronic structure and improve the efficiency of 2D ferroelectric solar cells.

Early distinction of bipolar disorder (BD) from major depressive disorder (MDD) is difficult since no tools are available to estimate the risk of BD. In this study, we aimed to develop and validate a model of oxidative stress injury for predicting BD. Data were collected from 1252 BD and 1359 MDD patients, including 64 MDD patients identified as converting to BD from 2009 through 2018. 30 variables from a randomly-selected subsample of 1827 (70%) patients were used to develop the model, including age, sex, oxidative stress markers (uric acid, bilirubin, albumin, and prealbumin), sex hormones, cytokines, thyroid and liver function, and glycolipid metabolism. Univariate analyses and the Least Absolute Shrinkage and Selection Operator were applied for data dimension reduction and variable selection. Multivariable logistic regression was used to construct a model for predicting bipolar disorder by oxidative stress biomarkers (BIOS) on a nomogram. Internal validation was assessed in the remaining 784 patients (30%), and independent external validation was done with data from 3797 matched patients from five other hospitals in China. 10 predictors, mainly oxidative stress markers, were shown on the nomogram. The BIOS model showed good discrimination in the training sample, with an AUC of 75.1% (95% CI: 72.9%-77.3%), sensitivity of 0.66, and specificity of 0.73. The discrimination was good both in internal validation (AUC 72.1%, 68.6%-75.6%) and external validation (AUC 65.7%, 63.9%-67.5%). In this study, we developed a nomogram centered on oxidative stress injury, which could help in the individualized prediction of BD. For better real-world practice, a set of measurements, especially on oxidative stress markers, should be emphasized using big data in psychiatry.

Ballast water has a negative impact on marine environment; the existing combined ultraviolet (UV) filtration system that for treating ballast water has relatively low effective rate and instability in inactivating microorganisms. In this study, the established high gradient magnetic separation-ultraviolet photocatalysis (HGMS-UV/TiO2) system was taken, the back propagation (BP) neural network and TracePro was used to simulate and analyse the UV field intensity in the system for optimizing. Further experimental verification was carried out with seawater sample to measure its inactivation effects on microorganisms including zooplankton, phytoplankton and bacteria. The results showed that HGMS-UVC/TiO2 system had good inactivation effect on zooplankton and bacteria, but relatively poor inactivation effect on phytoplankton. The optimal strategy for optimizing the UV intensity was further obtained, it is concluded that after adding ultraviolet A (UVA), the UV intensity distribution of the system is more uniform, and the average illumination intensity is also improved, but the optical path of UV in ballast water should not be too long. The optimized system could increase the intracellular K+ leakage of phytoplankton cells by more than 25%, indicating that the damage to cell membrane permeability was stronger. In conclusion, the optimized HGMS-UVA/UVC/TiO2 system can improve the inactivation capacity of microorganisms and provide basic theoretical support for improving the capacity and level of treatment in ballast water.

A series of adenine-containing polyimides (APIs) with intramolecular hydrogen bonding (HB) were prepared from N 1 -(9-(4-aminophenyl)- 9H-purin-6-yl)-2-methoxybenzene-1,4-diamine (b-H-MeO-APA) and commercial dianhydrides. And a systematic comparison between intramolecular and intermolecular HB effects was made using APIs with (b-H-MeO-APIs) and without (b-H-H-API) methoxy group. FTIR indicated that the occurrence of intramolecular HB originated from the side MeO group ortho to -NH-. XRD indicated that the introduction of side group MeO and corresponding intramolecular HB could destroy the orderly stacking of b-H-H-APIs. Birefringence and polarized ATR FTIR studies showed that the groups and chains in b-H-MeO-APIs films could also be simultaneously self-arranged in the in-plane direction. In contrast, the orientation degree in the in-plane direction is generally lower than that of b-H-H-APIs. The b-H-MeO-APIs films showed lower water absorption, higher Tg, and lower CTE compared to b-H-H-APIs films, which indicates that the introduction of intramolecular HB may have some positive influence in controlling water absorption, Tg, and CTE.

Methods for predicting the prognosis of patients undergoing surgery for recurrent hepatolithiasis after biliary surgery are currently lacking.To establish a nomogram to predict the prognosis of patients with recurrent hepatolithiasis after biliary surgery.In this multicenter, retrospective study, data of consecutive patients in four large medical centers who underwent surgery for recurrent hepatolithiasis after biliary surgery were retrospectively analyzed. We constructed a nomogram to predict the prognosis of recurrent hepatolithiasis in a training cohort of 299 patients, following which we independently tested the nomogram in an external validation cohort of 142 patients. Finally, we used the concordance index (C-index), calibra-tion, area under curve, decision curve analysis, clinical impact curves, and visual fit indices to evaluate the accuracy of the nomogram.Multiple previous surgeries [2 surgeries: Odds ratio (95% confidence interval), 1.451 (0.719-2.932); 3 surgeries: 4.573 (2.015-10.378); ≥ 4 surgeries: 5.741 (1.347-24.470)], bilateral hepatolithiasis [1.965 (1.039-3.717)], absence of immediate clearance [2.398 (1.304-4.409)], neutrophil-to-lymphocyte ratio ≥ 2.462 [1.915 (1.099-3.337)], and albumin-to-globulin ratio ≤ 1.5 [1.949 (1.056-3.595)] were found to be independent factors influencing the prognosis. The nomogram constructed on the basis of these variables showed good reliability in the training (C-index: 0.748) and validation (C-index: 0.743) cohorts. Compared with predictions using traditional classification models, those using our nomogram showed better agreement with actual observations in the calibration curve for the probability of endpoints and the receiver operating characteristic curve. Dichloroacetate and clinical impact curves showed a larger net benefit of the nomogram.The nomogram developed in this study demonstrated superior performance and discriminative power compared to the three traditional classifications. It is easy to use, highly accurate, and shows excellent calibration.

With the continuous development of road construction worldwide, the construction sector is trying to find a versatile material for building roads in particular areas. Air-foamed lightweight soil, which is produced using low-cost raw materials and has a lower density varying from 300 to 1800 kg/m3, adjustable strength, excellent thermal isolation, and a more straightforward construction method, has emerged as a worthy candidate. This paper reviews air-foamed lightweight soil in terms of its composition as well as physical and mechanical properties, such as its compressive strength, flexural strength, and stability. This paper also generalizes the engineering applications of air-foamed lightweight soil and provides ideas for its wide use.

Enhanced and reproducible SERS was obtained on a silver triangular nanoparticle/TiO2 nanoarray heterostructure.