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Background: This study aimed to assess physical activity level and identify specific types of exercises by sex, race/ethnicity, and age for adults 50 years and older. Methods: Behavioral Risk Factor Surveillance System 2013, 2015, and 2017 data were used to study US adults 50 years and older on their specific types of exercises, stratified by sex, race/ethnicity, and age. Weighted logistic regression was used to model physical exercise level and specific types of exercises. Results: The sample included 460,780 respondents. Non-Hispanic Black and Hispanic were less likely than non-Hispanic White to meet the recommended physical activity level (Odds ratio [OR] = 0.73, P <.0001 and OR = 0.96, P =.04, respectively). Walking was the most participated type of exercise, followed by gardening, for both men and women, all racial/ethnic groups, and all age groups. Non-Hispanic Blacks were more likely to participate in walking (OR = 1.19, P =.02) and less likely to participate in gardening (OR = 0.65, P <.0001) than non-Hispanic Whites. Men were more likely to engage in strenuous exercises than women. The average number of minutes on walking was the longest among all types of specific exercises. Conclusions: The types of exercises were mostly walking and gardening for adults aged 50 and older. Non-Hispanic Black adults had less physical activity than non-Hispanic White and were less likely to engage in gardening. [ABSTRACT FROM AUTHOR]

Herein, a facile hydrothermal method is utilized to prepare a (NH4)2V7O16/reduced graphene oxide (rGO) composite. In an aqueous electrolyte, the obtained (NH4)2V7O16/rGO exhibits superior lithium storage characteristics compared to pure (NH4)2V7O16 in both the three‐electrode configuration and full cell. This improvement can be ascribed to the synergistic effects of incorporation of defective oxygen and rGO modification. The present study proposes a feasible strategy for enhancing the electrochemical properties of (NH4)2V7O16 and demonstrates the potential of the (NH4)2V7O16/rGO composite for aqueous rechargeable lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

The Gradient Richardson Number (Ri) is an important parameter for appraising the stability and turbulence exchange at the atmospheric boundary layer (ABL). However, high-resolution measurements of Ri profiles are rarely reported, especially in megacities. In this study, a Doppler wind lidar and a microwave radiometer were simultaneously utilized to measure the 2 km Ri vertical profile in downtown Beijing. These measurements were verified to have high accuracy compared with observations from a 325 m meteorological tower, with root-mean-square errors (RMSEs) of less than 1.66 K, 7.9%, and 1.45 m/s for the temperature, relative humidity, and wind speed (WS) for all altitudes and corresponding Pearson correlation coefficients (R) of 0.97, 0.93, and 0.81. The inter-comparisons of different spatial (25 m, 50 m, 100 m) and temporal resolutions (1 min, 30 min, 1 h) form a 3 × 3 resolution matrix of Ri, in which the 1 h temporal resolution of Ri overestimates the intensity and active area of turbulence. The Ri value retrieved from the 100 m spatial resolution data overestimates these by half as it misidentifies the height of the stable area at the near surface. There are significant differences between the data with a 1 min temporal resolution and a 25 m spatial resolution (defined as the standard resolution of Ri), and the rest of the data in the resolution matrix (defined as data at other resolutions), with an RMSE > 1 and an R < 0.8. The difference between data at the standard resolution and data at other resolutions increases with elevations, which results from frequent weather processes or from water-vapor blocking at higher altitudes. The Ri profiles reveal that the atmospheric layer at altitudes from 100 m to 500 m in daytime is unstable, with Ri < 0, while it is neutral, with 0 < Ri < 0.25, at night-time from 200 m to 400 m. The atmosphere above the ABL in a megacity is rather stable, with Ri > 0.25, whereas below the ABL, it is neutral or unstable, which is due to drastic changes in the WS and temperature that are affected by the topography and surface friction. [ABSTRACT FROM AUTHOR]

In order to study the fine structural characteristics of the wind field and wind power generation in wind farms, large-eddy simulations (LES) with different layouts are carried out under a given wind direction. In the simulation, a single wind turbine can produce a wake effect, reducing the wind within 2 km by 50%, and the influence between wind turbines gradually decreases as the distance between the wind turbines increases. To minimize the impact of the wake effect between the turbines, the simulation considering horizontal and vertical staggering of the wind farm is conducted. Under the prevailing wind, the optimal power output for the entire wind farm is obtained when a horizontal staggering degree 6 of 16.7 is used and no vertical staggering is adapted. Unexpectedly, vertical interleaving hardly increases power generation in terms of the whole wind farm. This research result has certain implications for the optimal layout of wind farms in practical applications, especially in sites with a well-defined prevailing wind direction. [ABSTRACT FROM AUTHOR]

Based on a shipboard observation conducted in winter 2018, we reported the aerosol chemical properties and their differences in offshore and remote oceans over the Western Pacific Ocean (WPO). It's found that the chemical compositions over the WPO have significant spatial heterogeneity due to the influences of regional transport of anthropogenic aerosols and long‐path transport of dust aerosols. The average concentration of water soluble ions during the whole sampling period followed Cl− > OC > Na+ > SO42− ${{\text{SO}}_{4}}^{2-}$ > NO3− ${{\text{NO}}_{3}}^{-}$ > Ca2+ > Mg2+ > EC > K+ > NH4+ ${{\text{NH}}_{4}}^{+}$. Crustal elements of Ca (980.41 ng/m3), Na (971.55 ng/m3), and Al (781.16 ng/m3) were uniformly distributed in offshore area, but high proportion of Na elements dominated in remote regions. The total concentration of heavy metals including Zn, Cu, Cr, Pb and others originating from anthropogenic sources were 208 ng/m3 along the coastal region, about 10 times higher than that of 20.2 ng/m3 in the offshore and remote seas. For the reconstructed components, we found an increase of sea‐salt aerosol ranged from 3% to 72%, and a decrease of black carbon, organic matter and secondary inorganic salts, indicating a transformation from anthropogenic influence to marine environment. The rapidly increased secondary organic matter during dust event revealed that the transport of dust serves as catalysts to promote multi‐phase reactions. Cl− photochemical reaction rate in offshore area was mainly affected by sulfate from anthropogenic emissions, with an average chlorine loss rate of 18%, whereas it was inverse Cl− excess in the remote oceans. Plain Language Summary: The Institute of Oceanography, Chinese Academy of Sciences, organized a shipboard scientific observation over the Western Pacific Ocean (WPO) in winter 2018 to explore the chemical compositions of marine aerosols. The results showed that the chemical compositions over the WPO have significant spatial heterogeneity due to the different pollutants from various sources. Anthropogenic elements such as SO42− ${{\text{SO}}_{4}}^{2-}$, NO3− ${{\text{NO}}_{3}}^{-}$, and OC dominated in offshore waters, whereas the sea salt components of Na and Cl took a high proportion in remote oceans. In addition, dust aerosol originating from the North Africa also affected the WPO regions by long‐distance transport. The photochemical reaction rate of Cl− in offshore area was mainly affected by sulfate concentration from anthropogenic emissions, with an overall chlorine loss rate of 18%, but it exhibited an inversely Cl− excess phenomenon in the remote oceans. Key Points: The compositions of aerosol presented a significant change from anthropogenic source to marine sea salt from coast to remote oceansDust from North Africa acted as catalyst to promote the intensive formation of secondary organic aerosols in equatorial areaThere was a significant chlorine loss in the offshore coast, and a pronounced chlorine excess in remote seas [ABSTRACT FROM AUTHOR]

Existing deep reinforcement learning (DRL)-based methods for solving the capacitated vehicle routing problem (CVRP) intrinsically cope with a homogeneous vehicle fleet, in which the fleet is assumed as repetitions of a single vehicle. Hence, their key to construct a solution solely lies in the selection of the next node (customer) to visit excluding the selection of vehicle. However, vehicles in real-world scenarios are likely to be heterogeneous with different characteristics that affect their capacity (or travel speed), rendering existing DRL methods less effective. In this article, we tackle heterogeneous CVRP (HCVRP), where vehicles are mainly characterized by different capacities. We consider both min–max and min–sum objectives for HCVRP, which aim to minimize the longest or total travel time of the vehicle(s) in the fleet. To solve those problems, we propose a DRL method based on the attention mechanism with a vehicle selection decoder accounting for the heterogeneous fleet constraint and a node selection decoder accounting for the route construction, which learns to construct a solution by automatically selecting both a vehicle and a node for this vehicle at each step. Experimental results based on randomly generated instances show that, with desirable generalization to various problem sizes, our method outperforms the state-of-the-art DRL method and most of the conventional heuristics, and also delivers competitive performance against the state-of-the-art heuristic method, that is, slack induction by string removal. In addition, the results of extended experiments demonstrate that our method is also able to solve CVRPLib instances with satisfactory performance. [ABSTRACT FROM AUTHOR]

Wind power, as one of the primary clean energies, is an important way to achieve the goals of carbon peak and carbon neutrality. Therefore, high-resolution measurement and accurate forecasting of wind speed are very important in the organization and dispatching of the wind farm. In this study, several methodologies, including the mesoscale WRF (Weather Research and Forecasting(WRF) model, mathematical statistics algorithms, and machine learning algorithms, were adopted to systematically explore the predictability and optimization of wind speed of a Gobi grassland wind farm located in western Inner Mongolia. Results show that the rear-row turbines were significantly affected by upwind turbine wakes. The output power of upwind-group turbines was 591 KW with an average wind speed of 7.66 m/s, followed by 532 KW and 7.02 m/s in the middle group and 519 KW and 6.92 m/s in the downwind group. The higher the wind speed was, the more significantly the wake effect was presented. Intercomparison between observations and WRF simulations showed an average deviation of 3.73 m/s. Two postprocessing methods of bilinear interpolation and nearest replacement could effectively reduce the errors by 34.85% and 36.19%, respectively, with average deviations of 2.43 m/s and 2.38 m/s. A cycle correction algorithm named Average Variance–Trend (AVT) can further optimize the errors to 2.14 m/s and 2.13 m/s. In another aspect, the categorical boosting (CatBoost) artificial intelligence algorithm also showed a great performance in improving the accuracy of WRF outputs, and the four-day average deviation of 26–29 September decreased from 3.21 m/s to around 2.50 m/s. However, because of the influence of large-scale circulations, there still exist large errors in the results of various correction algorithms. It is therefore suggested through the investigation that data assimilation of the northwest and Mongolian plateau, boundary layer parameterization scheme optimization, and embedding of high-resolution topographic data could have great potential for obtaining more accurate forecasting products. [ABSTRACT FROM AUTHOR]

Toad venom, a dried product of secretion from Bufo bufo gargarizans Cantor or Bufo melanostictus Schneider, has had the therapeutic effects of hepatocellular carcinoma confirmed. Bufalin and cinobufagin were considered as the two most representative antitumor active components in toad venom. However, the underlying mechanisms of this antitumor effect have not been fully implemented, especially the changes in endogenous small molecules after treatment. Therefore, this study was designed to explore the intrinsic mechanism on hepatocellular carcinoma after the cotreatment of bufalin and cinobufagin based on untargeted tumor metabolomics. Ultraperformance liquid chromatography with tandem mass spectrometry (UHPLC-MS/MS) was performed to identify the absorbed components of toad venom in rat plasma. In vitro experiments were determined to evaluate the therapeutic effects of bufalin and cinobufagin and screen the optimal ratio between them. An in vivo HepG2 tumor-bearing nude mice model was established, and a series of pharmacodynamic indicators were determined, including the body weight of mice, tumor volume, tumor weight, and histopathological examination of tumor. Further, the entire metabolic alterations in tumor after treating with bufalin and cinobufagin were also profiled by UHPLC-MS/MS. Twenty-seven active components from toad venom were absorbed in rat plasma. We found that the cotreatment of bufalin and cinobufagin exerted significant antitumor effects both in vitro and in vivo, which were reflected in inhibiting proliferation and inducing apoptosis of HepG2 cells and thereby causing cell necrosis. After cotherapy of bufalin and cinobufagin for twenty days, compared with the normal group, fifty-six endogenous metabolites were obviously changed on HepG2 tumor-bearing nude mice. Meanwhile, the abundance of α-linolenic acid and phenethylamine after the bufalin and cinobufagin intervention was significantly upregulated, which involved phenylalanine metabolism and α-linolenic acid metabolism. Furthermore, we noticed that amino acid metabolites were also altered in HepG2 tumor after drug intervention, such as norvaline and Leu-Ala. Taken together, the cotreatment of bufalin and cinobufagin has significant antitumor effects on HepG2 tumor-bearing nude mice. Our work demonstrated that the in-depth mechanism of antitumor activity was mainly through the regulation of phenylalanine metabolism and α-Linolenic acid metabolism. [ABSTRACT FROM AUTHOR]

Rain-fed agriculture is easily affected by meteorological disasters, especially drought. As an important factor of risk formation, actively carrying out agricultural drought vulnerability assessments is conducive to improving food security and reducing economic losses. In this study, an SE-DEA model with regional exposure and drought risk as input factors and the maize yield reduction rate and drought-affected area as output factors is established. The aim is to evaluate and zone the drought vulnerability of the maize belt in the Songliao Plain. The results show the following: (1) From 2000 to 2019, the drought vulnerability of maize showed a fluctuating increasing trend. The vulnerability in Harbin and central Jilin Province is high, which is extremely unfavorable for maize production. (2) Comparing the historical disaster data with the drought vulnerability map generated using the SE-DEA model, it could be found that the results obtained using the SE-DEA model are reliable. (3) The Tobit model shows that the proportion of the effective irrigated area is more important to alleviate vulnerability. For drought vulnerability zoning using a cluster analysis, we suggest that regulated deficit irrigation should be actively developed in high-vulnerability areas to ensure maize yield while improving water efficiency. The results of this study can provide a basis for the development of drought mitigation and loss reduction strategies, and they provide new ideas for future research. [ABSTRACT FROM AUTHOR]

The negative impact of high-temperature disaster on agricultural production is becoming more and more serious, and reducing the vulnerability to high-temperature disaster is fundamental to achieving sustainable agricultural development. This study is mainly focused on the vulnerability to agricultural high-temperature disaster in Shaanxi Province, China. Firstly, 15 indicators were selected from the perspectives of exposure, sensitivity, and adaptability. Secondly, the combined weighting method (Critic-G1 model) was used to determine the weight of each index. Based on the aforementioned procedures, the Kullback–Leibler (KL)-distance-improved TOPSIS model was utilized to evaluate the vulnerability. Lastly, the obstacle model was used to analyze the influencing factors and to make recommendations for disaster prevention and mitigation. The results show that: (1) The improved TOPSIS model was closer to the results of the synthetical index method. (2) The northern and southern area of Shaanxi is more vulnerable to high-temperature disaster, especially in Ankang and Tongchuan. Low values are distributed in the Guanzhong Plain. (3) Sensitivity is the biggest obstacle to reducing the vulnerability to high-temperature disaster. Among the influencing factors, the meteorological yield reduction coefficient of variation, multiple cropping index and per capita net income of rural residents of the obstacle are high. Decreasing sensitivity should be accompanied by increasing adaptability to improve regional disaster preparedness and mitigation. The results of this study can provide a basis for the development of agricultural high-temperature disaster mitigation and loss reduction strategies and provide new ideas for future research. [ABSTRACT FROM AUTHOR]

Drought is a major natural disaster that causes a reduction in rain-fed maize yield. Agricultural drought risk assessment is conducive to improving regional disaster management ability, thereby reducing food security risks and economic losses. Considering the complexity of risk assessment research, an increasing number of researchers are focusing on the multiple-criteria decision-making (MCDM) method. However, the applicability of the MCDM method to agro-meteorological disaster risk assessments is not clear. Therefore, this study comprehensively evaluated hazard, exposure, vulnerability, and emergency response and recovery capability using the TOPSIS and VIKOR models to generate a maize drought risk map in mid-western Jilin Province and ranked the drought risk of each county. The results showed that: (1) maize drought risk in the middle and west of Jilin province showed an increasing trend. Spatially, the risk diminished from west to east. The drought risks faced by Tongyu, Changchun, and Dehui were more severe; (2) the evaluation results of the two models were verified using the yield reduction rate. The VIKOR model was found to be more suitable for agrometeorological drought risk assessments; (3) according to the damage degree of drought disaster to maize, the cluster analysis method was used to divide the study area into three sub-regions: safe, moderate drought, and severe drought. Combined with the characteristics of different regions, suggestions on disaster prevention and mitigation are proposed. The results of this study can provide a basis for formulating strategies to alleviate drought, reduce losses, and ensure the sustainable development of agriculture. [ABSTRACT FROM AUTHOR]

Aerosol optical depth (AOD) measurements for 2017–2020 in urban Hohhot of the Mongolian plateau, a transition zone between the depopulated zone and East Asian urban agglomeration, were analyzed for the first time. Results show that annual AOD500 and Ångström exponent α440-675 were 0.36 ± 0.09 and 1.11 ± 0.16 (2017), 0.41 ± 0.12 and 0.90 ± 0.28 (2018), 0.38 ± 0.09 and 1.13 ± 0.24 (2019), 0.38 ± 0.12 and 1.17 ± 0.22 (2020), respectively, representing a slightly polluted level with a mixed type of coarse dust aerosol and a fine urban/industrial aerosol. Throughout the year, depopulated-zone continental air flows predominated in Hohhot (i.e., NW-quadrant wind), accounting for 82.12% (spring), 74.54% (summer), 63.61% (autumn), and 100% (winter). The clean and strong NW-quadrant air flows induced by the south movement of a Siberian anticyclone resulted in a low 500-nm AOD of 0.30 ± 0.29, 0.20 ± 0.15, 0.24 ± 0.29, and 0.13 ± 0.08 from spring to winter. Meanwhile, the local emissions from Hohhot city, as well as anthropogenic urban/industrial aerosols transported by southern and western air masses, originating from southern urban agglomeration and western industrial cities (Baotou, Wuhai, etc.), contributed to the highest aerosol loading, with significant transformation rates of the secondary aerosols Sulfate-Nitrate-Ammonium (SNA) of 47.45%, 57.39%, 49.88%, and 45.16–47.36% in PM2.5 for each season. The extinction fraction of fine aerosols under these anthropogenic trajectories can be as high as 80%, and the largest fine aerosol size was around 0.2–0.25 μm. Dust aerosols were suspending in urban Hohhot all year, although at different levels for different seasons, and the extinction fraction of dust aerosol during sandstorms was generally higher than 70%. [ABSTRACT FROM AUTHOR]

Herein, (NH4)2V7O16 hierarchical structures formed by the self-assembly of nanoflakes were successfully synthesized by a one-step rotating hydrothermal method. When utilized as anodic materials for aqueous Li-ion batteries, the obtained (NH4)2V7O16 exhibited good rate capability and excellent cyclic stability. Moreover, the structural evolution of the ammonium vanadium bronze during cycling was also investigated by ex situ XRD. [ABSTRACT FROM AUTHOR]

Searching for novel anode materials to address the issues of poor cycle stability in the aqueous lithium‐ion battery system is highly desirable. In this work, ammonium vanadium bronze (NH4)2V7O16 with brick‐like morphology has been investigated as an anode material for aqueous lithium‐ion batteries and Li+/Na+ hybrid ion batteries. The two novel full cell systems (NH4)2V7O16||Li2SO4||LiMn2O4 and (NH4)2V7O16||Na2SO4||LiMn2O4 both demonstrate good rate capability and excellent cycling performance. A capacity retention of 78.61 % after 500 cycles at 300 mA g−1 was demonstrated in the (NH4)2V7O16||Li2SO4||LiMn2O4 system, whereas no capacity attenuation is observed in the (NH4)2V7O16||Na2SO4||LiMn2O4 system. The reaction mechanisms of the (NH4)2V7O16 electrode and impedance variation of the two full cells were also researched. The excellent cycling stability suggests that layered (NH4)2V7O16 can be a promising anode material for aqueous rechargeable lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

Difference and uncertainty of the aerosol radiative effects were quantified using the Santa Barbara DISORT Atmospheric Radiative Transfer model and multiple aerosol observation data sets from urban‐forest transition region. The secondary transformed carbonaceous aerosol components and biogenic secondary organic aerosol (BSOA) tracers have dominated over all other components (with a higher concentration in wet season) in terms of its impact on the aerosol radiative forcing (ARF). The averaged organic carbon (OC) and BSOA tracers increased from 13.3 ± 4.99 μg/m3, 29.5 ± 10.7 ng m−3 to 17.3 ± 4.47 μg/m3, 78.7 ± 43.7 ng m−3 in the dry and wet seasons, respectively. The corresponding root mean square errors of single scattering albedo and radiative forcing at the top of the atmosphere have increased by 8.4% and 16.9%. From the dry season to the wet season, the drastically aerosol composition and types variations caused the aerosol radiation effect reverse from cooling to heating. The increase in carbonaceous aerosols and BSOA transformed by forests in the wet season weakened the cooling effects. Driven by multiple factors, such as meteorological conditions, emission sources, and the mixed state of particulate matters, the transport patterns of air masses exhibit completely opposite effects to the ARF. Affected by the source location, wet deposition rate and components residence time, the uncertainty of ARF caused by long‐distance transport of aerosols is 68% higher than that of local aerosol situations under the condition of similar aerosol composition distributions. At similar transport distances, stronger aerosol secondary transformation increases the uncertainty of ARF by 20%. Plain Language Summary: Aerosol components have their ubiquitous nature and ability to mix with other aerosol types and affected by transport and deposition, increasing a bias in the estimation of aerosol radiative forcing. In this study, we demonstrated this potential impact from a measurement‐based perspective in a typical transition region in East China with abundant biogenic secondary organic aerosol emissions and quantified the uncertainty of the aerosol radiative forcing (ARF) caused by variations in aerosol composition. Different aerosol components will lead to the reversal of aerosol radiation effects in different seasons, and the increase in the proportion of secondary transformed aerosols will cause large uncertainty in ARF. Driven by multiple factors, aerosol transport distance also has a significant effect on uncertainties of ARF. Key Points: The aerosol properties and radiative effects show greatly seasonal differences over urban‐forest transition region in East ChinaThe differences of the aerosol components and secondary species transformation lead to obviously aerosol radiative forcing (ARF) uncertaintiesDriven by meteorological conditions, emission source and the persistent state of particulate matter, aerosol transport distance has a significant effect on uncertainties of ARF [ABSTRACT FROM AUTHOR]