BACKGROUND There has been an increasing focus in recent years on health-care disparities.Studies investigating return to work(RTW)or sports are often performed in large,urban areas.Relatively few studies have investig...BACKGROUND There has been an increasing focus in recent years on health-care disparities.Studies investigating return to work(RTW)or sports are often performed in large,urban areas.Relatively few studies have investigated rates of return to farming or other heavy labor that is of interest to patients in rural areas.AIM To evaluate the literature regarding RTW in farming or heavy labor after orthopedic hip,knee,or shoulder surgery.METHODS A search was performed in the PubMed and EMBASE databases using Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines.Studies were included if they reported patients employed in farming or heavy labor,RTW rates after orthopedic surgery of the hip,knee,or shoulder,and had a minimum 6-month follow-up.A meta-analysis of proportions using a random-effects model was performed on three single-arm observational studies to estimate the pooled RTW rate following arthroscopic shoulder surgery.RESULTS Ten studies were included,and 101 farmers were identified among 440 total patients.One study involved hip surgery,two studies involved knee surgery,and seven studies involved shoulder surgery.RTW rates across studies varied by type of surgery and follow-up interval,ranging from 24%to 100%.The RTW rate was only 53.6%at 1 year following total hip arthroplasty.No studies investigated RTW in farmers following total knee arthroplasty.Among non-comparative studies,meta-analysis revealed a pooled RTW rate of 89%following arthroscopic shoulder surgery,with low heterogeneity(I^(2)=30.1%).Among comparative studies,one study reported significantly higher RTW odds for patients undergoing anatomic total shoulder arthroplasty compared to reverse shoulder arthroplasty(odds ratio=5.45).Overall,surgical intervention for shoulder pathology was associated with a high likelihood of RTW across multiple techniques,with particularly favorable outcomes for anatomic total shoulder arthroplasty.CONCLUSION This systematic review highlights the high rates of RTW in farmers and heavy laborers after shoulder surgery.However,our findings also underscore the need for more rural-specific research to guide patient counseling,rehabilitation expectations,and shared decision-making in this underserved population,particularly for orthopedic surgery of the hip and knee.展开更多
BACKGROUND Return to work(RTW)serves as an indication for young and middle-aged colorectal cancer(CRC)survivors to resume their normal social lives.However,these survivors encounter significant challenges during their...BACKGROUND Return to work(RTW)serves as an indication for young and middle-aged colorectal cancer(CRC)survivors to resume their normal social lives.However,these survivors encounter significant challenges during their RTW process.Hence,scientific research is necessary to explore the barriers and facilitating factors of returning to work for young and middle-aged CRC survivors.AIM To examine the current RTW status among young and middle-aged CRC survivors and to analyze the impact of RTW self-efficacy(RTW-SE),fear of progression(FoP),eHealth literacy(eHL),family resilience(FR),and financial toxicity(FT)on their RTW outcomes.METHODS A cross-sectional investigation was adopted in this study.From September 2022 to February 2023,a total of 209 participants were recruited through a convenience sampling method from the gastrointestinal surgery department of a class A tertiary hospital in Chongqing.The investigation utilized a general information questionnaire alongside scales assessing RTW-SE,FoP,eHL,FR,and FT.To analyze the factors that influence RTW outcomes among young and middle-aged CRC survivors,Cox regression modeling and Kaplan-Meier survival analysis were used.RESULTS A total of 43.54%of the participants successfully returned to work,with an average RTW time of 100 days.Cox regression univariate analysis revealed that RTW-SE,FoP,eHL,FR,and FT were significantly different between the non-RTW and RTW groups(P<0.05).Furthermore,Cox regression multivariate analysis identified per capita family monthly income,job type,RTW-SE,and FR as independent influencing factors for RTW(P<0.05).CONCLUSION The RTW rate requires further improvement.Elevated levels of RTW-SE and FR were found to significantly increase RTW among young and middle-aged CRC survivors.Health professionals should focus on modifiable factors,such as RTW-SE and FR,to design targeted RTW support programs,thereby facilitating their timely reintegration into mainstream society.展开更多
Decision-makers usually have an aspiration level,a target,or a benchmark they aim to achieve.This behavior can be rationalized within the expected utility framework,which incorporates the probability of success(achiev...Decision-makers usually have an aspiration level,a target,or a benchmark they aim to achieve.This behavior can be rationalized within the expected utility framework,which incorporates the probability of success(achieving the aspiration level)as an important aspect of decision-making.Motivated by these theories,this study defines the probability of success as the number of days a firm’s return outperformed its benchmark in the portfolio formation month.This study uses portfolio-level and firm-level analyses,revealing an economically substantial and statistically significant relationship between the probability of success and expected stock returns,even after controlling for common risk factors and various characteristics.Additional analyses support the behavioral theory of the firm,which posits that firms act to achieve short-term aspiration levels.展开更多
BACKGROUND Pedicle screw instrumentation is a critical technique in spinal surgery,offering effective stabilization for various spinal conditions.However,the impact of intraoperative imaging quality—specifically the ...BACKGROUND Pedicle screw instrumentation is a critical technique in spinal surgery,offering effective stabilization for various spinal conditions.However,the impact of intraoperative imaging quality—specifically the use of both anteroposterior(AP)and lateral views—on surgical outcomes remains insufficiently studied.Evaluating whether the adequacy of these imaging modalities affects the risk of unplanned returns to theatre(URTT)within 90 days due to screw malplacement is essential for refining surgical practices and improving patient care.AIM To evaluate how intraoperative imaging adequacy influences unplanned returnto-theatre rates,focusing on AP and lateral fluoroscopic views.METHODS This retrospective cohort study analyzed 1335 patients who underwent thoracolumbar and sacral pedicle screw instrumentation between January 2013 and December 2022.Data on intraoperative imaging adequacy,screw placement,and URTT events were collected and statistically analyzed using IBM SPSS v23.Imaging adequacy was assessed based on the presence of both AP and lateral views,and outcomes were compared between imaging groups.RESULTS A total of 9016 pedicle screws were inserted,with 82 screws identified as malplaced in 52 patients.Of these,46 patients required URTT due to screw malplacement,with 37 returning within 90 days(URTT90).Patients with both AP and lateral imaging saved intraoperatively had significantly lower URTT90 rates compared to those with only lateral imaging saved,demonstrating the critical role of imaging adequacy in improving surgical outcomes.CONCLUSION This study underscores that comprehensive intraoperative imaging with both AP and lateral views reduces unplanned returns,improves outcomes,enhances precision,and offers a cost-effective approach for better spinal surgery results.展开更多
Background: Lumbar disc herniation is a common injury among athletes, especially those who practice disciplines with repetitive flexion movements, twisting and axial loading on the spine, such as weightlifting, gymnas...Background: Lumbar disc herniation is a common injury among athletes, especially those who practice disciplines with repetitive flexion movements, twisting and axial loading on the spine, such as weightlifting, gymnastics, hockey and American football. In refractory cases to conservative treatment, microscopic discectomy or full endoscopic discectomy are used as surgical options to relieve pain and restore patient functionality. However, the ideal time for a return to sports activities remains a matter of debate due to variations in recovery times and risks of complications associated with each technique. Methods: A review was conducted, including articles published in the last 33 years (1991-2024), as it was the earliest date matching our search criteria. Clinical studies, systematic reviews, meta-analyses, and clinical guidelines were included. Results: The most common complications when returning to sport prematurely include recurrence of the hernia, persistent pain (VAS leg 7 or higher after surgery) and reduced physical performance. The return to full activity rate of patients who underwent microdiscectomy reaches up to 90%, while the endoscopic technique shows a success rate that reaches 99%. Return to play meantime was 5.19 months (range 1.00 - 8.7 months) and mean time of 4.6 months (range 2 - 8 months) with Microdiscectomy and full endoscopic discectomy respectively. Conclusions: There is no unanimous consensus on the exact timing of return to sport due to variability in recovery times and clinical outcomes. In both techniques, evidence highlights the need for a multidisciplinary approach that integrates surgeons, physical therapists and trainers to optimize recovery and ensure a safe return.展开更多
The Shenzhou‑18 crew,consisting of three taikonauts,returned to Earth safely in the early hours of November 4,2024,after completing a six‑month space station mission.Their first meal on Earth after half a year became ...The Shenzhou‑18 crew,consisting of three taikonauts,returned to Earth safely in the early hours of November 4,2024,after completing a six‑month space station mission.Their first meal on Earth after half a year became a hot topic immediately.The well‑established Chinese tradition embodied by the saying“dumplings before departure,noodles upon return”means that a steaming bowl of noodles was a must‑have for their first meal back.Additionally,specific fruits were included in their first meal for symbolic purposes:cherry tomatoes,representing prosperity;Hami melons,symbolizing sweetness;and grapes,which signify harmony and unity.Meanwhile,all three taikonauts coincidentally ordered a serving of steamed egg custard.展开更多
During his second White House term,Trump’s governing style remains characteristically assertive,launching a full-scale offensive from day one.Domestically,he’s pushing for sweeping government reforms.
The practice of conservation tillage or straw return to the farmland influences the grain yield and quality of rice(Oryza sativa).The key volatile compound responsible for the fragrance of fragrant rice is 2-acetyl-1-...The practice of conservation tillage or straw return to the farmland influences the grain yield and quality of rice(Oryza sativa).The key volatile compound responsible for the fragrance of fragrant rice is 2-acetyl-1-pyrroline(2-AP),which is significantly affected by field management measures.The purpose of this study was to investigate the impact of tillage management and straw return on the grain yield and biosynthesis of 2-AP in fragrant rice.This study was conducted over two years in 2016 and 2017 and used two fragrant rice cultivars(Meixiangzhan 2 and Xiangyaxiangzhan)as materials.The experimental design consisted of different tillage management and straw return treatments,which included three tillage management regimes:rotary tillage(T0),minimum tillage(T1),and no tillage(T2);and two straw return treatments:without straw return(S0)and straw return(S1).The straw used for the experiment was sourced from the residue of the corresponding fragrant rice cultivar harvested in the early season.Tillage management and straw return substantially affected the grain yields,grain quality,and 2-AP contents of both fragrant rice cultivars.Compared with the T0S0 treatment,tillage management and straw return resulted in 2-AP content improvements in 2016(12.41–116.85%)and 2017(34.85–103.89%)on average.Higher 2-AP contents were also detected in both fragrant rice cultivars in the T2S1 and T1S1 treatments.A structural equation model(SEM)demonstrated that the activities of enzymes related to fragrance metabolism in the leaves and grain jointly regulated the biosynthesis of precursors of fragrance metabolism in the grain,which further promoted the accumulation of 2-AP.In addition,a principal component analysis indicated that the T1S1 treatment was positively correlated with both 2-AP and grain yield.The SEM demonstrated that the enzymes related to nitrogen metabolism,parameters related to photosynthesis,and yield components contributed to the grain yield.The T1S1 treatment resulted in the highest average grain yield of 760.75 g m^(-2),which could be attributed to increases in various attributes,such as the leaf area index,SPAD value,nitrogen metabolism,panicle number m^(-2),and grain number per panicle.In summary,the minimum tillage and straw return(T1S1)treatment is more effective at simultaneously improving both the grain yield and 2-AP content in fragrant rice.展开更多
Improving crop yield and N utilization while mitigating environmental pollution is a key goal in sustainable agriculture.Integrating green manure with reduced chemical N application is a promising strategy to enhance ...Improving crop yield and N utilization while mitigating environmental pollution is a key goal in sustainable agriculture.Integrating green manure with reduced chemical N application is a promising strategy to enhance N utilization efficiency and minimize reactive N losses.However,the agronomic mechanisms through which green manure incorporation affects soil N retention and N loss under reduced N application remain unclear.This study aimed to uncover the compensatory mechanisms of green manure in improving wheat yield and N utilization under reduced N application,and to identify the principles behind reduced N loss in wheat fields.We conducted a split-plot experiment in the Hexi Oasis irrigation area of Northwest China from 2019 to 2024,using two cropping systems(W,fallow after wheat;W-G,green manure returning after wheat)combined with three N application levels(N1,local conventional N application rate;N2,N-reduction 15%;N3,N-reduction 30%).Our results demonstrated that green manure returning improved soil quality and compensated for the yield and N use efficiency losses caused by 15%chemical N reduction.Specifically,compared to the W-N1,W-GN2 increased soil organic matter content and soil water content by 6.5%and 9.4%,respectively,while reducing soil bulk density and pH by 8.9%and 6.7%.Meanwhile,W-GN2 increased soil nitrate N and total N content in the 0–40 cm soil layer by 8.4%and 8.7%,respectively.Moreover,W-GN2 reduced NH3 volatilization by 13.8%,N_(2)O emissions by 8.8%,and N leaching by 9.4%.It also enhanced microbial biomass N by 50.7%,urease activity by 10.2%,and decreased nitrate and nitrite reductase activities by 19.9%and 32.6%,respectively.Additionally,W-GN2 improved soil bacterialα-diversity and increased the abundance of functional bacteria.Green manure can sustain wheat yield and improve N utilization efficiency under reduced chemical N input by improving the soil environment,enhancing soil N retention and minimizing N losses,which presents a sustainable,yield-stabilizing strategy for Oasis agroecosystems in northwestern China.展开更多
The mineral composition of the sinter affects the quality of cold-bonded briquettes(CBB),which are prepared from returned sinter fines and serve as a cleaner blast furnace charge.Pulverization rate,compressive strengt...The mineral composition of the sinter affects the quality of cold-bonded briquettes(CBB),which are prepared from returned sinter fines and serve as a cleaner blast furnace charge.Pulverization rate,compressive strength,reduction disintegration index(RDI)and compressive strength after reduction experiment were tested to analyze the experimental parameters of CBB under the influence of different basicities and sintering time.The results show that when the basicity of CBB is increased from 0.5 to 1.5,the pulverization rate increases,and performance indexes such as compressive strength,RDI,and compressive strength exhibit a decreasing trend.When the basicity is increased from 1.5 to 3.0,all the aforementioned performance indexes are improved.When the sintering time is extended from 0 to 8 h,the properties mentioned above are improved.The results of X-ray diffraction,microstructure,and thermodynamic calculations confirm that the hematite in the mineral composition of CBB tends to convert into calcium ferrite,which leads to the increased compressive strength of CBB.The reasonable basicity and sintering time during sinter preparation not only form the desired mineral composition but also improve the properties of the CBB.展开更多
BACKGROUND Return to work(RTW)and resumption of driving(ROD)are critical factors that influence postoperative quality of life in patients undergoing total hip arthroplasty(THA).However,few studies have focused on the ...BACKGROUND Return to work(RTW)and resumption of driving(ROD)are critical factors that influence postoperative quality of life in patients undergoing total hip arthroplasty(THA).However,few studies have focused on the minimally invasive(MIS)approach and its effect on these outcomes.AIM To investigate RTW and ROD's timelines and influencing factors following anterior MIS-THA.METHODS A retrospective analysis was conducted on 124 patients who underwent anterior MIS-THA.Data on the demographics,occupational physical demands,and RTW/ROD timelines were also collected.Clinical outcomes were measured using standardised scoring systems.Statistical analyses were performed to evaluate the differences between the groups based on employment status and physical workload.RESULTS Among employed patients,the RTW rate was 94.7%,with an average return time of five weeks.The average ROD time was 3.5 weeks across all patients.Despite similar postoperative clinical scores,RTW time was significantly influenced by occupations'physical workload,with heavier physical demands associated with delayed RTW.CONCLUSION Anterior MIS-THA facilitates early RTW and ROD,particularly in occupations with lower physical demands.These findings highlight the importance of considering occupational and physical workload in postoperative care planning to optimize recovery outcomes.展开更多
Stock return prediction has been in the spotlight because it involves numerous factors.Improving the accuracy of stock return prediction and quantifying the impact of individual factors on forecasting remain challengi...Stock return prediction has been in the spotlight because it involves numerous factors.Improving the accuracy of stock return prediction and quantifying the impact of individual factors on forecasting remain challenging tasks.Motivated by these challenges,we propose a novel forecasting method that entails proxy variables of category factors and the random forest technique.This new method aims to quantify the information and importance of category factors,thereby enhancing the predictability of stock returns.Specifically,we categorize a large set of return predictors into several category factors.We then utilize the importance of the original variables to construct proxy variables for these category factors.Subsequently,we use the proxy variables to build a random forest model for predicting stock returns.Our empirical analysis results demonstrate that the proposed method effectively quantifies the importance of both the original factors and category factors.Furthermore,we find that the fundamental information factor consistently ranks as the most crucial category factor for stock return forecasting.Additionally,the proposed method exhibits a more robust and prominent prediction performance than competing models such as single-category-factor-based random forest models,dimension-reduction,and forecast-combination methods.Most importantly,the proposed method produces forecast results that can assist investors with understanding stock market dynamics and facilitate higher investment returns.展开更多
In recent years,load balancing routing al-gorithms have been extensively studied in satellite net-works.Most existing studies focus on path selection and hop-count optimization for end-to-end transmis-sion,while overl...In recent years,load balancing routing al-gorithms have been extensively studied in satellite net-works.Most existing studies focus on path selection and hop-count optimization for end-to-end transmis-sion,while overlooking congestion issues on feeder links caused by the limited number and centralized distribution of ground stations.Hence,a multi-service routing algorithm called the Multi-service Load Bal-ancing Routing Algorithm for Traffic Return(MLB-TR)is proposed.Unlike traditional approaches,MLB-TR aims to achieve a broader and more comprehensive load balancing objective.Specifically,based on the service type,an appropriate landing satellite is first selected by considering factors such as shortest path hop count and satellite load.Then,a set of candidate paths from the source satellite to the selected landing satellite is computed.Finally,using the regional load balancing index as the optimization objective,the final transmission path is selected from the candidate path set.Simulation results show that the proposed algo-rithm outperforms the existing works.展开更多
Huailai County in Zhangjiakou was taken as the research area.Based on daily temperature data from 1992 to 2021,various methods were used to analyze the characteristics of extreme temperature changes in the region and ...Huailai County in Zhangjiakou was taken as the research area.Based on daily temperature data from 1992 to 2021,various methods were used to analyze the characteristics of extreme temperature changes in the region and estimate extreme temperature values for different return periods.The results showed that from 1992 to 2021,both the annual average maximum and minimum temperatures in Huailai County exhibited a slight downward trend,with continuous low temperatures from 2010 to 2012;the annual average extreme maximum temperature slightly decreased,reaching a peak in 2010,with July being the concentrated period of extreme high temperatures;the extreme minimum temperature"continuously cooled down"with multiple occurrences of low temperatures in the past decade and a decrease in the number of high temperature days.The estimation of return periods based on the Gumbel distribution indicates that the temperature values for different return periods vary between the highest and lowest temperature months,and the longer the return period,the more significant the extreme temperature values and the larger the standard deviation.The research can provide a basis for local agricultural development.展开更多
This study investigates the significance of e-commerce consumer opinions regarding value in China’s A-share market.By analyzing a large dataset comprising over 18 million online consumer reviews on JD.com,we demonstr...This study investigates the significance of e-commerce consumer opinions regarding value in China’s A-share market.By analyzing a large dataset comprising over 18 million online consumer reviews on JD.com,we demonstrate that sentiments expressed in e-commerce reviews can influence stock returns.This indicates that consumer opinions on the e-commerce platform contain valuable information that can impact the stock market.Our findings show that Consumer Negative Sentiment Tendency(CNST)and One-Star Tendency(OST)have a negative effect on expected stock returns,even after controlling for firm characteristics such as market risk,illiquidity,idiosyncratic volatility,and asset growth.Further analysis indicates that CNST demonstrates stronger predictive power within the home appliance industry,under high sentiment conditions,in growth companies,and among firms with lower accounting transparency.We also find that CNST negatively predicts revenue surprises,earnings surprises,and cash flow shocks.These results suggest that consumer opinions and sentiments derived from e-commerce reviews highlight firms’intrinsic worth and prospects.Future research could explore how firms,including suppliers and logistics companies,can leverage the information conveyed by consumer opinions on e-commerce platforms.展开更多
Aimed at the demand of contingency return at any time during the near-moon phase in the manned lunar landing missions,a fast calculation method for three-impulse contingency return trajectories is proposed.Firstly,a t...Aimed at the demand of contingency return at any time during the near-moon phase in the manned lunar landing missions,a fast calculation method for three-impulse contingency return trajectories is proposed.Firstly,a three-impulse contingency return trajectory scheme is presented by combining the Lambert transfer and maneuver at the special point.Secondly,a calculation model of three-impulse contingency return trajectories is established.Then,fast calculation methods are proposed by adopting the high-order Taylor expansion of differential algebra in the twobody trajectory dynamics model and perturbed trajectory dynamics model.Finally,the performance of the proposed methods is verified by numerical simulation.The results indicate that the fast calculation method of two-body trajectory has higher calculation efficiency compared to the semi-analytical calculation method under a certain accuracy condition.Due to its high efficiency,the characteristics of the three-impulse contingency return trajectories under different contingency scenarios are further analyzed expeditiously.These findings can be used for the design of contingency return trajectories in future manned lunar landing missions.展开更多
Long-term straw return with appropriate nitrogen(N)fertilization increases seedcotton yield and fiber quality,and the root system plays an important role in cotton production.However,under straw return and N fertiliza...Long-term straw return with appropriate nitrogen(N)fertilization increases seedcotton yield and fiber quality,and the root system plays an important role in cotton production.However,under straw return and N fertilization,the relationship between the cotton boll-loading capacity of the root system and seedcotton yield remains unclear.In this study,a ten years of long-term field experiment was conducted in a wheat-cotton rotation system.The effects of straw treatments(straw return and straw removal)and N rates(N0,N75,N150 and N300 representing 0,75,150 and 300 kg N ha^(-1),respectively)on cotton root activity,boll-loading capacity of the root system and their relationship to seedcotton yield from 2019 to 2022 were quantified.The results showed that straw return with an appropriate N fertilization of N150 increased root biomass,the rate and components of root-bleeding sap,as well as boll-loading capacity of the root system and seedcotton yield,but decreased the ratio of root to shoot biomass.Furthermore,the root-bleeding sap rate reached the maximum at 30 d post anthesis(DPA)during the peak boll setting stage.However,the contents of nitrate-N,free amino acids and soluble sugar in root-bleeding sap decreased from 10 DPA.Notably,in 2021 and at 30 DPA,the highest contents of nitrate-N(4.8μg mL^(-1))and free amino acids(8.3μg mL^(-1)),as well as soluble sugar(3.4μg mL^(-1))were observed at N150 under straw return.The increase in seedcotton yield is positively correlated to the soluble sugar content.Straw return significantly increased the boll-loading capacity of the root system,which first increased but then decreased with the increase in N fertilization.Under straw return with N150,the maximum seecotton yield(3455-4544 kg ha^(-1))was recorded,and the largest boll loading(49-54 boll 100 g^(-1))and boll capacity(242-292 g 100 g^(-1))of root system at the boll opening stage were observed.Therefore,straw return with appropriate N fertilization improved root activity and the boll-loading capacity of the root system,thereby increasing seedcotton yield.This study provides new insights into improving seedcotton yield from the perspective of coordinating cotton growth.展开更多
This paper examines how a change in health policy uncertainty affects US industry returns using monthly data from January 1985 to September 2020.We employ insample and out-of-sample analyses,and we find evidence that ...This paper examines how a change in health policy uncertainty affects US industry returns using monthly data from January 1985 to September 2020.We employ insample and out-of-sample analyses,and we find evidence that 25 out of 49 considered industries are predictable during the health crisis periods,including severe acute respiratory syndrome and the ongoing coronavirus pandemic.The out-of-sample tests corroborate the evidence for the in-sample predictability.Furthermore,using a mean–variance utility function-based trading strategy,we observe that investors can use this simple tool for their trading strategies and make profits from 2.99 to 11.44%per annum.Our findings are robust after accounting for different business cycles,macroeconomic factor effects,the fluctuation in economic policy uncertainty,and different pandemic phases.These results complement the existing literature on industry return predictability and have potential implications for asset pricing and risk management.展开更多
Frequent extreme heat events exacerbated by global warming pose a significant threat to human health.However,the dynamic changes in human thermal comfort during such regional extremes remain understudied.This study in...Frequent extreme heat events exacerbated by global warming pose a significant threat to human health.However,the dynamic changes in human thermal comfort during such regional extremes remain understudied.This study investigates the spatiotemporal characteristics of the Universal Thermal Climate Index(UTCI)during 5-year return period extreme heat events across the Beijing-Tianjin-Hebei(BTH)region of China,utilizing 40 years of meteorological data from 174 stations.A non-stationary Generalized Extreme Value distribution model with a location parameter link function was identified as the optimal model(for 65.3%of stations)through the Akaike Information Criterion,capturing 16 regional extreme heat events.Results indicate that extreme heat thresholds rise with increasing return periods,with the highest thresholds concentrated around Beijing and Shijiazhuang.Air temperature and mean radiant temperature were found to be the dominant factors influencing UTCI,with daytime air temperature contributing 47.03%to 50.64%and nighttime mean radiant temperature contributing up to 48.55%.Spatially,“extreme heat stress”conditions,as defined by UTCI,were predominantly observed in the southeastern plains of Beijing and southern Hebei Province.Diurnally,UTCI peaked between 1200 and 1600 BT(Beijing time),generally returning to“no heat stress”levels across most areas between 0000 and 0600 BT.These findings provide crucial insights into the dynamics of human thermal comfort during extreme heat events in the BTH region,offering valuable scientific support for developing targeted heat mitigation and adaptation strategies.展开更多
This study uses Baidu News data and introduces a novel proxy for the rate of information flow to examine its relationship with return volatility in Chinese commodity futures and to test two competing hypotheses.We exa...This study uses Baidu News data and introduces a novel proxy for the rate of information flow to examine its relationship with return volatility in Chinese commodity futures and to test two competing hypotheses.We examine the contemporaneous relationships using correlation coefficient analysis,and find apparent differences between the information flow-return volatility relationship and the information flowtrading volume relationship.The empirical evidence contradicts the mixture of distribution hypothesis(MDH)and suggests that the rate of information flow distinctly affects trading volume and volatility.We conducted linear and nonlinear Granger causality tests to explore the sequential information arrival hypothesis(SIAH).The empirical results prove that a lead-lag linear and nonlinear causality exists between the information flow and return volatility of commodity futures,which is consistent with SIAH.In other words,a partial equilibrium exists before reaching the ultimate equilibrium when the new information arrives in the market.Finally,these findings are robust to alternative measurement of return volatility and subperiod analysis.Our findings reject the MDH and support the SIAH in the context of Chinese commodity futures.展开更多
文摘BACKGROUND There has been an increasing focus in recent years on health-care disparities.Studies investigating return to work(RTW)or sports are often performed in large,urban areas.Relatively few studies have investigated rates of return to farming or other heavy labor that is of interest to patients in rural areas.AIM To evaluate the literature regarding RTW in farming or heavy labor after orthopedic hip,knee,or shoulder surgery.METHODS A search was performed in the PubMed and EMBASE databases using Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines.Studies were included if they reported patients employed in farming or heavy labor,RTW rates after orthopedic surgery of the hip,knee,or shoulder,and had a minimum 6-month follow-up.A meta-analysis of proportions using a random-effects model was performed on three single-arm observational studies to estimate the pooled RTW rate following arthroscopic shoulder surgery.RESULTS Ten studies were included,and 101 farmers were identified among 440 total patients.One study involved hip surgery,two studies involved knee surgery,and seven studies involved shoulder surgery.RTW rates across studies varied by type of surgery and follow-up interval,ranging from 24%to 100%.The RTW rate was only 53.6%at 1 year following total hip arthroplasty.No studies investigated RTW in farmers following total knee arthroplasty.Among non-comparative studies,meta-analysis revealed a pooled RTW rate of 89%following arthroscopic shoulder surgery,with low heterogeneity(I^(2)=30.1%).Among comparative studies,one study reported significantly higher RTW odds for patients undergoing anatomic total shoulder arthroplasty compared to reverse shoulder arthroplasty(odds ratio=5.45).Overall,surgical intervention for shoulder pathology was associated with a high likelihood of RTW across multiple techniques,with particularly favorable outcomes for anatomic total shoulder arthroplasty.CONCLUSION This systematic review highlights the high rates of RTW in farmers and heavy laborers after shoulder surgery.However,our findings also underscore the need for more rural-specific research to guide patient counseling,rehabilitation expectations,and shared decision-making in this underserved population,particularly for orthopedic surgery of the hip and knee.
基金Supported by the Chongqing Medical University Program for Youth Innovation in Future Medicine,No.W0019Chongqing Municipal Education Commission’s 14th Five-Year Key Discipline Support Project,No.20240101 and No.20240102。
文摘BACKGROUND Return to work(RTW)serves as an indication for young and middle-aged colorectal cancer(CRC)survivors to resume their normal social lives.However,these survivors encounter significant challenges during their RTW process.Hence,scientific research is necessary to explore the barriers and facilitating factors of returning to work for young and middle-aged CRC survivors.AIM To examine the current RTW status among young and middle-aged CRC survivors and to analyze the impact of RTW self-efficacy(RTW-SE),fear of progression(FoP),eHealth literacy(eHL),family resilience(FR),and financial toxicity(FT)on their RTW outcomes.METHODS A cross-sectional investigation was adopted in this study.From September 2022 to February 2023,a total of 209 participants were recruited through a convenience sampling method from the gastrointestinal surgery department of a class A tertiary hospital in Chongqing.The investigation utilized a general information questionnaire alongside scales assessing RTW-SE,FoP,eHL,FR,and FT.To analyze the factors that influence RTW outcomes among young and middle-aged CRC survivors,Cox regression modeling and Kaplan-Meier survival analysis were used.RESULTS A total of 43.54%of the participants successfully returned to work,with an average RTW time of 100 days.Cox regression univariate analysis revealed that RTW-SE,FoP,eHL,FR,and FT were significantly different between the non-RTW and RTW groups(P<0.05).Furthermore,Cox regression multivariate analysis identified per capita family monthly income,job type,RTW-SE,and FR as independent influencing factors for RTW(P<0.05).CONCLUSION The RTW rate requires further improvement.Elevated levels of RTW-SE and FR were found to significantly increase RTW among young and middle-aged CRC survivors.Health professionals should focus on modifiable factors,such as RTW-SE and FR,to design targeted RTW support programs,thereby facilitating their timely reintegration into mainstream society.
文摘Decision-makers usually have an aspiration level,a target,or a benchmark they aim to achieve.This behavior can be rationalized within the expected utility framework,which incorporates the probability of success(achieving the aspiration level)as an important aspect of decision-making.Motivated by these theories,this study defines the probability of success as the number of days a firm’s return outperformed its benchmark in the portfolio formation month.This study uses portfolio-level and firm-level analyses,revealing an economically substantial and statistically significant relationship between the probability of success and expected stock returns,even after controlling for common risk factors and various characteristics.Additional analyses support the behavioral theory of the firm,which posits that firms act to achieve short-term aspiration levels.
文摘BACKGROUND Pedicle screw instrumentation is a critical technique in spinal surgery,offering effective stabilization for various spinal conditions.However,the impact of intraoperative imaging quality—specifically the use of both anteroposterior(AP)and lateral views—on surgical outcomes remains insufficiently studied.Evaluating whether the adequacy of these imaging modalities affects the risk of unplanned returns to theatre(URTT)within 90 days due to screw malplacement is essential for refining surgical practices and improving patient care.AIM To evaluate how intraoperative imaging adequacy influences unplanned returnto-theatre rates,focusing on AP and lateral fluoroscopic views.METHODS This retrospective cohort study analyzed 1335 patients who underwent thoracolumbar and sacral pedicle screw instrumentation between January 2013 and December 2022.Data on intraoperative imaging adequacy,screw placement,and URTT events were collected and statistically analyzed using IBM SPSS v23.Imaging adequacy was assessed based on the presence of both AP and lateral views,and outcomes were compared between imaging groups.RESULTS A total of 9016 pedicle screws were inserted,with 82 screws identified as malplaced in 52 patients.Of these,46 patients required URTT due to screw malplacement,with 37 returning within 90 days(URTT90).Patients with both AP and lateral imaging saved intraoperatively had significantly lower URTT90 rates compared to those with only lateral imaging saved,demonstrating the critical role of imaging adequacy in improving surgical outcomes.CONCLUSION This study underscores that comprehensive intraoperative imaging with both AP and lateral views reduces unplanned returns,improves outcomes,enhances precision,and offers a cost-effective approach for better spinal surgery results.
文摘Background: Lumbar disc herniation is a common injury among athletes, especially those who practice disciplines with repetitive flexion movements, twisting and axial loading on the spine, such as weightlifting, gymnastics, hockey and American football. In refractory cases to conservative treatment, microscopic discectomy or full endoscopic discectomy are used as surgical options to relieve pain and restore patient functionality. However, the ideal time for a return to sports activities remains a matter of debate due to variations in recovery times and risks of complications associated with each technique. Methods: A review was conducted, including articles published in the last 33 years (1991-2024), as it was the earliest date matching our search criteria. Clinical studies, systematic reviews, meta-analyses, and clinical guidelines were included. Results: The most common complications when returning to sport prematurely include recurrence of the hernia, persistent pain (VAS leg 7 or higher after surgery) and reduced physical performance. The return to full activity rate of patients who underwent microdiscectomy reaches up to 90%, while the endoscopic technique shows a success rate that reaches 99%. Return to play meantime was 5.19 months (range 1.00 - 8.7 months) and mean time of 4.6 months (range 2 - 8 months) with Microdiscectomy and full endoscopic discectomy respectively. Conclusions: There is no unanimous consensus on the exact timing of return to sport due to variability in recovery times and clinical outcomes. In both techniques, evidence highlights the need for a multidisciplinary approach that integrates surgeons, physical therapists and trainers to optimize recovery and ensure a safe return.
文摘The Shenzhou‑18 crew,consisting of three taikonauts,returned to Earth safely in the early hours of November 4,2024,after completing a six‑month space station mission.Their first meal on Earth after half a year became a hot topic immediately.The well‑established Chinese tradition embodied by the saying“dumplings before departure,noodles upon return”means that a steaming bowl of noodles was a must‑have for their first meal back.Additionally,specific fruits were included in their first meal for symbolic purposes:cherry tomatoes,representing prosperity;Hami melons,symbolizing sweetness;and grapes,which signify harmony and unity.Meanwhile,all three taikonauts coincidentally ordered a serving of steamed egg custard.
文摘During his second White House term,Trump’s governing style remains characteristically assertive,launching a full-scale offensive from day one.Domestically,he’s pushing for sweeping government reforms.
基金funding provided by the National Natural Science Foundation of China(31971843 and 31271646)the Guangxi Natural Science Foundation,China(2021GXNSFBA196084)。
文摘The practice of conservation tillage or straw return to the farmland influences the grain yield and quality of rice(Oryza sativa).The key volatile compound responsible for the fragrance of fragrant rice is 2-acetyl-1-pyrroline(2-AP),which is significantly affected by field management measures.The purpose of this study was to investigate the impact of tillage management and straw return on the grain yield and biosynthesis of 2-AP in fragrant rice.This study was conducted over two years in 2016 and 2017 and used two fragrant rice cultivars(Meixiangzhan 2 and Xiangyaxiangzhan)as materials.The experimental design consisted of different tillage management and straw return treatments,which included three tillage management regimes:rotary tillage(T0),minimum tillage(T1),and no tillage(T2);and two straw return treatments:without straw return(S0)and straw return(S1).The straw used for the experiment was sourced from the residue of the corresponding fragrant rice cultivar harvested in the early season.Tillage management and straw return substantially affected the grain yields,grain quality,and 2-AP contents of both fragrant rice cultivars.Compared with the T0S0 treatment,tillage management and straw return resulted in 2-AP content improvements in 2016(12.41–116.85%)and 2017(34.85–103.89%)on average.Higher 2-AP contents were also detected in both fragrant rice cultivars in the T2S1 and T1S1 treatments.A structural equation model(SEM)demonstrated that the activities of enzymes related to fragrance metabolism in the leaves and grain jointly regulated the biosynthesis of precursors of fragrance metabolism in the grain,which further promoted the accumulation of 2-AP.In addition,a principal component analysis indicated that the T1S1 treatment was positively correlated with both 2-AP and grain yield.The SEM demonstrated that the enzymes related to nitrogen metabolism,parameters related to photosynthesis,and yield components contributed to the grain yield.The T1S1 treatment resulted in the highest average grain yield of 760.75 g m^(-2),which could be attributed to increases in various attributes,such as the leaf area index,SPAD value,nitrogen metabolism,panicle number m^(-2),and grain number per panicle.In summary,the minimum tillage and straw return(T1S1)treatment is more effective at simultaneously improving both the grain yield and 2-AP content in fragrant rice.
基金financial support of the Science and Technology Program in Gansu province(25JRRA347,24ZDNA008)the Natural Science Foundation of China(32372238,U21A20218,32460547)+4 种基金the Industrial Support Project of Educational Committee of Gansu province(2025CYZC-037)the Research Program Sponsored by State Key Laboratory of Aridland Crop Science(GSCS-2023-Z03)the Agricultural Research System of China(CARS-22-G-12)China Agricultural University Corresponding Support Research Joint Fund(GSAU-DKZY-2024-001)the UPTAKE Project on EU Horizon(101081521).
文摘Improving crop yield and N utilization while mitigating environmental pollution is a key goal in sustainable agriculture.Integrating green manure with reduced chemical N application is a promising strategy to enhance N utilization efficiency and minimize reactive N losses.However,the agronomic mechanisms through which green manure incorporation affects soil N retention and N loss under reduced N application remain unclear.This study aimed to uncover the compensatory mechanisms of green manure in improving wheat yield and N utilization under reduced N application,and to identify the principles behind reduced N loss in wheat fields.We conducted a split-plot experiment in the Hexi Oasis irrigation area of Northwest China from 2019 to 2024,using two cropping systems(W,fallow after wheat;W-G,green manure returning after wheat)combined with three N application levels(N1,local conventional N application rate;N2,N-reduction 15%;N3,N-reduction 30%).Our results demonstrated that green manure returning improved soil quality and compensated for the yield and N use efficiency losses caused by 15%chemical N reduction.Specifically,compared to the W-N1,W-GN2 increased soil organic matter content and soil water content by 6.5%and 9.4%,respectively,while reducing soil bulk density and pH by 8.9%and 6.7%.Meanwhile,W-GN2 increased soil nitrate N and total N content in the 0–40 cm soil layer by 8.4%and 8.7%,respectively.Moreover,W-GN2 reduced NH3 volatilization by 13.8%,N_(2)O emissions by 8.8%,and N leaching by 9.4%.It also enhanced microbial biomass N by 50.7%,urease activity by 10.2%,and decreased nitrate and nitrite reductase activities by 19.9%and 32.6%,respectively.Additionally,W-GN2 improved soil bacterialα-diversity and increased the abundance of functional bacteria.Green manure can sustain wheat yield and improve N utilization efficiency under reduced chemical N input by improving the soil environment,enhancing soil N retention and minimizing N losses,which presents a sustainable,yield-stabilizing strategy for Oasis agroecosystems in northwestern China.
基金supported by Distinguished Professor(Tracking Plan)of Oriental Scholars of Shanghai Universities(Grant No.GZ2020013)National 111 Project(The Program of Introducing Talents of Discipline to University)(Grant No.Dl7002)+1 种基金Independent Research Project of State Key Laboratory of Advanced Special Steel Shanghai Key Laboratory of Advanced Ferrometallurgy and Shanghai University(Grant No.SKLASS 2022-Z011)Additionally,the authors are appreciative of the funding from the Academy of Finland with Grant No.349833.
文摘The mineral composition of the sinter affects the quality of cold-bonded briquettes(CBB),which are prepared from returned sinter fines and serve as a cleaner blast furnace charge.Pulverization rate,compressive strength,reduction disintegration index(RDI)and compressive strength after reduction experiment were tested to analyze the experimental parameters of CBB under the influence of different basicities and sintering time.The results show that when the basicity of CBB is increased from 0.5 to 1.5,the pulverization rate increases,and performance indexes such as compressive strength,RDI,and compressive strength exhibit a decreasing trend.When the basicity is increased from 1.5 to 3.0,all the aforementioned performance indexes are improved.When the sintering time is extended from 0 to 8 h,the properties mentioned above are improved.The results of X-ray diffraction,microstructure,and thermodynamic calculations confirm that the hematite in the mineral composition of CBB tends to convert into calcium ferrite,which leads to the increased compressive strength of CBB.The reasonable basicity and sintering time during sinter preparation not only form the desired mineral composition but also improve the properties of the CBB.
基金approved by the Institutional Ethics Committee of Shizuoka Red Cross Hospital(No.2023-36,approval date:January 12,2024).
文摘BACKGROUND Return to work(RTW)and resumption of driving(ROD)are critical factors that influence postoperative quality of life in patients undergoing total hip arthroplasty(THA).However,few studies have focused on the minimally invasive(MIS)approach and its effect on these outcomes.AIM To investigate RTW and ROD's timelines and influencing factors following anterior MIS-THA.METHODS A retrospective analysis was conducted on 124 patients who underwent anterior MIS-THA.Data on the demographics,occupational physical demands,and RTW/ROD timelines were also collected.Clinical outcomes were measured using standardised scoring systems.Statistical analyses were performed to evaluate the differences between the groups based on employment status and physical workload.RESULTS Among employed patients,the RTW rate was 94.7%,with an average return time of five weeks.The average ROD time was 3.5 weeks across all patients.Despite similar postoperative clinical scores,RTW time was significantly influenced by occupations'physical workload,with heavier physical demands associated with delayed RTW.CONCLUSION Anterior MIS-THA facilitates early RTW and ROD,particularly in occupations with lower physical demands.These findings highlight the importance of considering occupational and physical workload in postoperative care planning to optimize recovery outcomes.
基金supported by the National Natural Science Foundation of China(Grant No.72403117,U1901223,72271095)the Natural Science Foundation of Jiangsu Province,China(Grant No.BK20241435)+1 种基金Guangzhou Philosophy and Social Science Project(Grant No.x2gsN5180360)the Fundamental Research Funds for the Central Universities(Grant No.30923011034).
文摘Stock return prediction has been in the spotlight because it involves numerous factors.Improving the accuracy of stock return prediction and quantifying the impact of individual factors on forecasting remain challenging tasks.Motivated by these challenges,we propose a novel forecasting method that entails proxy variables of category factors and the random forest technique.This new method aims to quantify the information and importance of category factors,thereby enhancing the predictability of stock returns.Specifically,we categorize a large set of return predictors into several category factors.We then utilize the importance of the original variables to construct proxy variables for these category factors.Subsequently,we use the proxy variables to build a random forest model for predicting stock returns.Our empirical analysis results demonstrate that the proposed method effectively quantifies the importance of both the original factors and category factors.Furthermore,we find that the fundamental information factor consistently ranks as the most crucial category factor for stock return forecasting.Additionally,the proposed method exhibits a more robust and prominent prediction performance than competing models such as single-category-factor-based random forest models,dimension-reduction,and forecast-combination methods.Most importantly,the proposed method produces forecast results that can assist investors with understanding stock market dynamics and facilitate higher investment returns.
基金supported by the National Key Research and Development Program of China under Grant No.2022YFB2902501the Fundamental Research Funds for the Central Universities under Grant No.2023ZCJH09the Haidian District Golden Bridge Seed Fund of Beijing Municipality under Grant No.S2024161.
文摘In recent years,load balancing routing al-gorithms have been extensively studied in satellite net-works.Most existing studies focus on path selection and hop-count optimization for end-to-end transmis-sion,while overlooking congestion issues on feeder links caused by the limited number and centralized distribution of ground stations.Hence,a multi-service routing algorithm called the Multi-service Load Bal-ancing Routing Algorithm for Traffic Return(MLB-TR)is proposed.Unlike traditional approaches,MLB-TR aims to achieve a broader and more comprehensive load balancing objective.Specifically,based on the service type,an appropriate landing satellite is first selected by considering factors such as shortest path hop count and satellite load.Then,a set of candidate paths from the source satellite to the selected landing satellite is computed.Finally,using the regional load balancing index as the optimization objective,the final transmission path is selected from the candidate path set.Simulation results show that the proposed algo-rithm outperforms the existing works.
文摘Huailai County in Zhangjiakou was taken as the research area.Based on daily temperature data from 1992 to 2021,various methods were used to analyze the characteristics of extreme temperature changes in the region and estimate extreme temperature values for different return periods.The results showed that from 1992 to 2021,both the annual average maximum and minimum temperatures in Huailai County exhibited a slight downward trend,with continuous low temperatures from 2010 to 2012;the annual average extreme maximum temperature slightly decreased,reaching a peak in 2010,with July being the concentrated period of extreme high temperatures;the extreme minimum temperature"continuously cooled down"with multiple occurrences of low temperatures in the past decade and a decrease in the number of high temperature days.The estimation of return periods based on the Gumbel distribution indicates that the temperature values for different return periods vary between the highest and lowest temperature months,and the longer the return period,the more significant the extreme temperature values and the larger the standard deviation.The research can provide a basis for local agricultural development.
基金supported by the National Natural Science Foundation of China under projects No.62302319R&D Program of Beijing Municipal Education Commission(Grant No.KM202210038002).
文摘This study investigates the significance of e-commerce consumer opinions regarding value in China’s A-share market.By analyzing a large dataset comprising over 18 million online consumer reviews on JD.com,we demonstrate that sentiments expressed in e-commerce reviews can influence stock returns.This indicates that consumer opinions on the e-commerce platform contain valuable information that can impact the stock market.Our findings show that Consumer Negative Sentiment Tendency(CNST)and One-Star Tendency(OST)have a negative effect on expected stock returns,even after controlling for firm characteristics such as market risk,illiquidity,idiosyncratic volatility,and asset growth.Further analysis indicates that CNST demonstrates stronger predictive power within the home appliance industry,under high sentiment conditions,in growth companies,and among firms with lower accounting transparency.We also find that CNST negatively predicts revenue surprises,earnings surprises,and cash flow shocks.These results suggest that consumer opinions and sentiments derived from e-commerce reviews highlight firms’intrinsic worth and prospects.Future research could explore how firms,including suppliers and logistics companies,can leverage the information conveyed by consumer opinions on e-commerce platforms.
基金co-supported by the National Natural Science Foundation of China(No.12072365)the Technology Innovation Team of Manned Space Engineering,China。
文摘Aimed at the demand of contingency return at any time during the near-moon phase in the manned lunar landing missions,a fast calculation method for three-impulse contingency return trajectories is proposed.Firstly,a three-impulse contingency return trajectory scheme is presented by combining the Lambert transfer and maneuver at the special point.Secondly,a calculation model of three-impulse contingency return trajectories is established.Then,fast calculation methods are proposed by adopting the high-order Taylor expansion of differential algebra in the twobody trajectory dynamics model and perturbed trajectory dynamics model.Finally,the performance of the proposed methods is verified by numerical simulation.The results indicate that the fast calculation method of two-body trajectory has higher calculation efficiency compared to the semi-analytical calculation method under a certain accuracy condition.Due to its high efficiency,the characteristics of the three-impulse contingency return trajectories under different contingency scenarios are further analyzed expeditiously.These findings can be used for the design of contingency return trajectories in future manned lunar landing missions.
基金supported by the Jiangsu Agricultural Science and Technology Innovation Fund(CX(22)2015)the Fundamental Research Funds for the Central Universities(XUEKEN2022008)+1 种基金the Innovation Center for Modern Crop Production Cosponsored by Province and Ministry(CIC-MCP)the Cotton Industry Technology Research System of Shandong Province(SDAIT-03).
文摘Long-term straw return with appropriate nitrogen(N)fertilization increases seedcotton yield and fiber quality,and the root system plays an important role in cotton production.However,under straw return and N fertilization,the relationship between the cotton boll-loading capacity of the root system and seedcotton yield remains unclear.In this study,a ten years of long-term field experiment was conducted in a wheat-cotton rotation system.The effects of straw treatments(straw return and straw removal)and N rates(N0,N75,N150 and N300 representing 0,75,150 and 300 kg N ha^(-1),respectively)on cotton root activity,boll-loading capacity of the root system and their relationship to seedcotton yield from 2019 to 2022 were quantified.The results showed that straw return with an appropriate N fertilization of N150 increased root biomass,the rate and components of root-bleeding sap,as well as boll-loading capacity of the root system and seedcotton yield,but decreased the ratio of root to shoot biomass.Furthermore,the root-bleeding sap rate reached the maximum at 30 d post anthesis(DPA)during the peak boll setting stage.However,the contents of nitrate-N,free amino acids and soluble sugar in root-bleeding sap decreased from 10 DPA.Notably,in 2021 and at 30 DPA,the highest contents of nitrate-N(4.8μg mL^(-1))and free amino acids(8.3μg mL^(-1)),as well as soluble sugar(3.4μg mL^(-1))were observed at N150 under straw return.The increase in seedcotton yield is positively correlated to the soluble sugar content.Straw return significantly increased the boll-loading capacity of the root system,which first increased but then decreased with the increase in N fertilization.Under straw return with N150,the maximum seecotton yield(3455-4544 kg ha^(-1))was recorded,and the largest boll loading(49-54 boll 100 g^(-1))and boll capacity(242-292 g 100 g^(-1))of root system at the boll opening stage were observed.Therefore,straw return with appropriate N fertilization improved root activity and the boll-loading capacity of the root system,thereby increasing seedcotton yield.This study provides new insights into improving seedcotton yield from the perspective of coordinating cotton growth.
文摘This paper examines how a change in health policy uncertainty affects US industry returns using monthly data from January 1985 to September 2020.We employ insample and out-of-sample analyses,and we find evidence that 25 out of 49 considered industries are predictable during the health crisis periods,including severe acute respiratory syndrome and the ongoing coronavirus pandemic.The out-of-sample tests corroborate the evidence for the in-sample predictability.Furthermore,using a mean–variance utility function-based trading strategy,we observe that investors can use this simple tool for their trading strategies and make profits from 2.99 to 11.44%per annum.Our findings are robust after accounting for different business cycles,macroeconomic factor effects,the fluctuation in economic policy uncertainty,and different pandemic phases.These results complement the existing literature on industry return predictability and have potential implications for asset pricing and risk management.
基金supported by the Hebei Provincial Key Research and Development Program[grant numbers 23375401D and22375404D]the China Meteorological Administration[grant number FPZJ2024-011]the Hebei Meteorological Bureau[grant number21ky32]。
文摘Frequent extreme heat events exacerbated by global warming pose a significant threat to human health.However,the dynamic changes in human thermal comfort during such regional extremes remain understudied.This study investigates the spatiotemporal characteristics of the Universal Thermal Climate Index(UTCI)during 5-year return period extreme heat events across the Beijing-Tianjin-Hebei(BTH)region of China,utilizing 40 years of meteorological data from 174 stations.A non-stationary Generalized Extreme Value distribution model with a location parameter link function was identified as the optimal model(for 65.3%of stations)through the Akaike Information Criterion,capturing 16 regional extreme heat events.Results indicate that extreme heat thresholds rise with increasing return periods,with the highest thresholds concentrated around Beijing and Shijiazhuang.Air temperature and mean radiant temperature were found to be the dominant factors influencing UTCI,with daytime air temperature contributing 47.03%to 50.64%and nighttime mean radiant temperature contributing up to 48.55%.Spatially,“extreme heat stress”conditions,as defined by UTCI,were predominantly observed in the southeastern plains of Beijing and southern Hebei Province.Diurnally,UTCI peaked between 1200 and 1600 BT(Beijing time),generally returning to“no heat stress”levels across most areas between 0000 and 0600 BT.These findings provide crucial insights into the dynamics of human thermal comfort during extreme heat events in the BTH region,offering valuable scientific support for developing targeted heat mitigation and adaptation strategies.
基金supported by the National Social Science Fund of China(24CGL027)the National Natural Science Foundation of China(72101009,72141304,72201122)National Key Research and Development Program of China(2022YFC3303304).
文摘This study uses Baidu News data and introduces a novel proxy for the rate of information flow to examine its relationship with return volatility in Chinese commodity futures and to test two competing hypotheses.We examine the contemporaneous relationships using correlation coefficient analysis,and find apparent differences between the information flow-return volatility relationship and the information flowtrading volume relationship.The empirical evidence contradicts the mixture of distribution hypothesis(MDH)and suggests that the rate of information flow distinctly affects trading volume and volatility.We conducted linear and nonlinear Granger causality tests to explore the sequential information arrival hypothesis(SIAH).The empirical results prove that a lead-lag linear and nonlinear causality exists between the information flow and return volatility of commodity futures,which is consistent with SIAH.In other words,a partial equilibrium exists before reaching the ultimate equilibrium when the new information arrives in the market.Finally,these findings are robust to alternative measurement of return volatility and subperiod analysis.Our findings reject the MDH and support the SIAH in the context of Chinese commodity futures.
