BACKGROUND:Community-acquired bloodstream infections(CABSIs)are common in the emergency departments,and some progress to sepsis and even lead to death.However,limited information is available regarding the prediction ...BACKGROUND:Community-acquired bloodstream infections(CABSIs)are common in the emergency departments,and some progress to sepsis and even lead to death.However,limited information is available regarding the prediction of patients with high risk of death.METHODS:The Emergency Bloodstream Infection Score(EBS)for CABSIs was developed to visualize the output of a logistic regression model and was validated by the area under the curve(AUC).The Mortality in Emergency Department Sepsis(MEDS),Pitt Bacteremia Score(PBS),Sequential Organ Failure Assessment(SOFA),quick Sequential Organ Failure Assessment(qSOFA),Charlson Comorbidity Index(CCI),and McCabe–Jackson Comorbid Classification(MJCC)for patients with CABSIs were computed to compare them with EBS in terms of the AUC and decision curve analysis(DCA).The net reclassification improvement(NRI)index and integrated discrimination improvement(IDI)index were compared between the SOFA and EBS.RESULTS:A total of 547 patients with CABSIs were included.The AUC(0.853)of the EBS was larger than those of the MEDS,PBS,SOFA,and qSOFA(all P<0.001).The NRI index of EBS in predicting the in-hospital mortality of CABSIs patients was 0.368(P=0.04),and the IDI index was 0.079(P=0.03).DCA showed that when the threshold probability was<0.1,the net benefit of the EBS model was higher than those of the other models.CONCLUSION:The EBS prognostic models were better than the SOFA,qSOFA,MEDS,and PBS models in predicting the in-hospital mortality of patients with CABSIs.展开更多
This study was designed to find out an optimised planting system of reducing non-point (source) pollution by analyzing the reasons and the factors of influence non-point pollution in farmland of Erhai Lake basin. Th...This study was designed to find out an optimised planting system of reducing non-point (source) pollution by analyzing the reasons and the factors of influence non-point pollution in farmland of Erhai Lake basin. The results showed that incomes, residual nitrogen in soil, and the loss of nitrogen in surface water in rice-garlic system were higher than those in rice-fava bean system. There were positive correlations between the nitrogen loss of farmland, nitrogen inputs, residual nitrogen in soil, and incomes of farmland. Economic benefits and environment benefits are both appropriate, if the area of rice-garlic system would be reduced to 53% and the area of rice-fava bean system increased to 36% of total cropping area in the investigated watershed. Adjustment of planting structure and introduction of reasonable rotation systems is considered an effective measure of controlling agricultural non-point pollution in watersheds of Erhai Lake.展开更多
Background: Forest managers must deal with inherently stochastic ecological and economic processes. The future growth of trees is uncertain, and so is their value. The randomness of low-impact, high frequency or rare...Background: Forest managers must deal with inherently stochastic ecological and economic processes. The future growth of trees is uncertain, and so is their value. The randomness of low-impact, high frequency or rare catastrophic shocks in forest growth has significant implications in shaping the mix of tree species and the forest landscape. In addition, the fluctuations of wood prices influence greatly forest revenues. Methods: Markov decision process models (MDPs) offer a rigorous and practical way of developing optimum management strategies, given these multiple sources of risk. Results: Examples illustrate how such management guidelines are obtained with MDPs for combined ecological and economic objectives, including diversity of tree species and size, landscape diversity, old growth preservation, and carbon sequestration. Conclusions: The findings illustrate the power of the MDP approach to deal with risk in forest resource management. They recognize that the future is best viewed in terms of probabilities. Given these probabilities, MDPs tie optimum adaptive actions strictly to the state of the forest and timber prices at decision time. The methods are theoretically rigorous, numerically efficient, and practical for field implementation.展开更多
In this research, soil samples were collected from Shandong Peninsula Blue Economic Zone to investigate heavy metal pollutions in this region and to evaluate the potential ecological risks of heavy metal pollutants ba...In this research, soil samples were collected from Shandong Peninsula Blue Economic Zone to investigate heavy metal pollutions in this region and to evaluate the potential ecological risks of heavy metal pollutants based on Hakanson Potential Ecological Risk Indexes. According to the results, Hg was the primary heavy metal pollutant in Blue Economic Zone, followed by Cd, Cu, and Pb as prevalent pollutants. Heavy metals ranked in order of their pollution degrees are: Hg>Cd>Cu>Pb>Zn>Cr>As;the potential ecological risks of heavy metals follow the order of Hg>Cd>As>Pb>Cu>Cr>Zn. Heavy metal pollutions did exist in this region to a certain extent, and the percentage of potential ecological risk in “strong” and “severe” degree reached up to 13.75%. This composite risk characteristic was subject to the restriction of Hg and Cd mainly distributed in Laizhou-Zhaoyuan- Yantai, Muping-Rushan Goldmine, and other densely-populated regions, threatening the safety production of crops. The combined effects of geological background and human activities, e.g. gold mining and domestic pollutants, were the main causes of high potential ecological risks of heavy metals in local environment.展开更多
AIM: To evaluate the association between various lifestyle factors and achalasia risk.METHODS: A population-based case-control study was conducted in Northern Ireland, including n = 151 achalasia cases and n = 117 age...AIM: To evaluate the association between various lifestyle factors and achalasia risk.METHODS: A population-based case-control study was conducted in Northern Ireland, including n = 151 achalasia cases and n = 117 age- and sexmatched controls. Lifestyle factors were assessed via a face-to-face structured interview. The association between achalasia and lifestyle factors was assessed by unconditional logistic regression, to produce odds ratios(OR) and 95% confidence interval(CI).RESULTS: Individuals who had low-class occupations were at the highest risk of achalasia(OR = 1.88, 95%CI: 1.02-3.45), inferring that high-class occupation holders have a reduced risk of achalasia. A history of foreign travel, a lifestyle factor linked to upper socioeconomic class, was also associated with a reduced risk of achalasia(OR = 0.59, 95%CI: 0.35-0.99). Smoking and alcohol consumption carried significantly reduced risks of achalasia, even after adjustment for socio-economic status. The presence of pets in the house was associated with a two-fold increased risk of achalasia(OR = 2.00, 95%CI: 1.17-3.42). Nochildhood household factors were associated with achalasia risk.CONCLUSION: Achalasia is a disease of inequality, and individuals from low socio-economic backgrounds are at highest risk. This does not appear to be due to corresponding alcohol and smoking behaviours. An observed positive association between pet ownership and achalasia risk suggests an interaction between endotoxin and viral infection exposure in achalasia aetiology.展开更多
Based on the precautionary theory,this paper established a framework for consumption of migrant workers from the perspective of the uncertainty risk,and analyzed the effects of uncertain income risk on consumption of ...Based on the precautionary theory,this paper established a framework for consumption of migrant workers from the perspective of the uncertainty risk,and analyzed the effects of uncertain income risk on consumption of migrant workers using the quantile regression method.Results indicated that the income uncertainty significantly inhibits the consumption of migrant workers. The lower the consumption level or the lower the income level,the stronger the inhibitory effect will be. Uncertainty of expenditure also has a significant inhibitory effect on the consumption of migrant workers. Promoting urbanization of migrant workers and accelerating the reform of the household registration system can reduce the uncertainty risks faced by migrant workers,so as to raise the consumption expectation of migrant workers,release the consumption potential of migrant workers,and improve the living standards of migrant workers.展开更多
Based on the global asset portfolio model,this paper created a panel threshold model using EPFR fund data to empirically test the non-linear spillover effects of US economic policy uncertainties on cross-border capita...Based on the global asset portfolio model,this paper created a panel threshold model using EPFR fund data to empirically test the non-linear spillover effects of US economic policy uncertainties on cross-border capital flow for emerging economies.Our study led to the following findings:(1)When the level of global investor risk tolerance is high,rising US EPU will induce a capital inflow into emerging economies,as manifested in the“portfolio rebalancing effect.”When the level of global investor risk tolerance is below a critical threshold,this gives rise to risk aversion and emerging economies will experience net capital outflow,i.e.the“flight to quality effect”.(2)Equity fund investors have a lower risk tolerance threshold than bond fund investors.(3)According to our heterogeneity analysis,more attention should be paid to monitoring capital flow through actively managed funds,ETF funds,and retail investor funds.The economy should increase financial efficiency and economic resiliency to mitigate capital outflow pressures from the external environment.展开更多
In 2010, China entered the advanced stage of industrialization, which coincided with the country's entry into a new stage of economic growth. However, this transition is associated with major risks, including adaptin...In 2010, China entered the advanced stage of industrialization, which coincided with the country's entry into a new stage of economic growth. However, this transition is associated with major risks, including adapting to decelerating economic growth. While recognizing the move toward a service-based economy, China must seek to prevent the risk of "manufacturing hollowing out. "' It must also avoid the "technology upgrade trap" while taking advantage of increasingly sophisticated industrial structures. Efforts must also be made to: (1) promote the integration of lT tools and meet risks arising from the New Industrial Revolution; (2) resolve liability risks arising from capacity reduction; and (3) expedite the transition to a functional industrial policy and prevent the failure of a functional industrial policy. In climbing up the global value chain, China must confront the competitive pressures from advanced and emerging economies on both high- and low-end processes of the global value chain.展开更多
A reliable economic risk map is critical for effective debris-flow mitigation.However,the uncertainties surrounding future scenarios in debris-flow frequency and magnitude restrict its application.To estimate the econ...A reliable economic risk map is critical for effective debris-flow mitigation.However,the uncertainties surrounding future scenarios in debris-flow frequency and magnitude restrict its application.To estimate the economic risks caused by future debris flows,a machine learning-based method was proposed to generate an economic risk map by multiplying a debris-flow hazard map and an economic vulnerability map.We selected the Gyirong Zangbo Basin as the study area because frequent severe debris flows impact the area every year.The debris-flow hazard map was developed through the multiplication of the annual probability of spatial impact,temporal probability,and annual susceptibility.We employed a hybrid machine learning model-certainty factor-genetic algorithm-support vector classification-to calculate susceptibilities.Simultaneously,a Poisson model was applied for temporal probabilities,while the determination of annual probability of spatial impact relied on statistical results.Additionally,four major elements at risk were selected for the generation of an economic loss map:roads,vegetation-covered land,residential buildings,and farmland.The economic loss of elements at risk was calculated based on physical vulnerabilities and their economic values.Therefore,we proposed a physical vulnerability matrix for residential buildings,factoring in impact pressure on buildings and their horizontal distance and vertical distance to debrisflow channels.In this context,an ensemble model(XGBoost) was used to predict debris-flow volumes to calculate impact pressures on buildings.The results show that residential buildings occupy 76.7% of the total economic risk,while roadcovered areas contribute approximately 6.85%.Vegetation-covered land and farmland collectively represent 16.45% of the entire risk.These findings can provide a scientific support for the effective mitigation of future debris flows.展开更多
This paper investigates the impact of economic policy uncertainty(EPU)on the crash risk of US stock market during the COVID-19 pandemic.To this end,we use the GARCHS(GARCH with skewness)model to estimate daily skewnes...This paper investigates the impact of economic policy uncertainty(EPU)on the crash risk of US stock market during the COVID-19 pandemic.To this end,we use the GARCHS(GARCH with skewness)model to estimate daily skewness as a proxy for the stock market crash risk.The empirical results show the significantly negative correlation between EPU and stock market crash risk,indicating the aggravation of EPU increase the crash risk.Moreover,the negative correlation gets stronger after the global COVID-19 outbreak,which shows the crash risk of the US stock market will be more affected by EPU during the epidemic.展开更多
A novel approach was proposed to allocate spinning reserve for dynamic economic dispatch.The proposed approach set up a two-stage stochastic programming model to allocate reserve.The model was solved using a decompose...A novel approach was proposed to allocate spinning reserve for dynamic economic dispatch.The proposed approach set up a two-stage stochastic programming model to allocate reserve.The model was solved using a decomposed algorithm based on Benders' decomposition.The model and the algorithm were applied to a simple 3-node system and an actual 445-node system for verification,respectively.Test results show that the model can save 84.5 US $ cost for the testing three-node system,and the algorithm can solve the model for 445-node system within 5 min.The test results also illustrate that the proposed approach is efficient and suitable for large system calculation.展开更多
Online banking fraud occurs whenever a criminal can seize accounts and transfer funds from an individual’s online bank account.Successfully preventing this requires the detection of as many fraudsters as possible,wit...Online banking fraud occurs whenever a criminal can seize accounts and transfer funds from an individual’s online bank account.Successfully preventing this requires the detection of as many fraudsters as possible,without producing too many false alarms.This is a challenge for machine learning owing to the extremely imbalanced data and complexity of fraud.In addition,classical machine learning methods must be extended,minimizing expected financial losses.Finally,fraud can only be combated systematically and economically if the risks and costs in payment channels are known.We define three models that overcome these challenges:machine learning-based fraud detection,economic optimization of machine learning results,and a risk model to predict the risk of fraud while considering countermeasures.The models were tested utilizing real data.Our machine learning model alone reduces the expected and unexpected losses in the three aggregated payment channels by 15%compared to a benchmark consisting of static if-then rules.Optimizing the machine-learning model further reduces the expected losses by 52%.These results hold with a low false positive rate of 0.4%.Thus,the risk framework of the three models is viable from a business and risk perspective.展开更多
BACKGROUND Intracranial hemorrhage after spinal surgery is a rare and devastating complication.AIM To investigate the economic burden,clinical characteristics,risk factors,and mechanisms of intracranial hemorrhage aft...BACKGROUND Intracranial hemorrhage after spinal surgery is a rare and devastating complication.AIM To investigate the economic burden,clinical characteristics,risk factors,and mechanisms of intracranial hemorrhage after spinal surgery.METHODS A retrospective cohort study was conducted from January 1,2015,to December 31,2022.Patients aged≥18 years,who had undergone spinal surgery were included.Intracranial hemorrhage patients were selected after spinal surgery during hospitalization.Based on the type of spinal surgery,patients with intracranial hemorrhage were randomly matched in a 1:5 ratio with control patients without intracranial hemorrhage.The patients'pre-,intra-,and post-operative data and clinical manifestations were recorded.RESULTS A total of 24472 patients underwent spinal surgery.Six patients(3 males and 3 females,average age 71.3 years)developed intracranial hemorrhage after posterior spinal fusion procedures,with an incidence of 0.025%(6/24472).The prevailing type of intracranial hemorrhage was cerebellar hemorrhage.Two patients had a poor clinical outcome.Based on the type of surgery,30 control patients were randomly matched in 1:5 ratio.The intracranial hemorrhage group showed significant differences compared with the control group with regard to age(71.33±7.45 years vs 58.39±8.07 years,P=0.001),previous history of cerebrovascular disease(50%vs 6.7%,P=0.024),spinal dura mater injury(50%vs 3.3%,P=0.010),hospital expenses(RMB 242119.1±87610.0 vs RMB 96290.7±32029.9,P=0.009),and discharge activity daily living score(40.00±25.88 vs 75.40±18.29,P=0.019).CONCLUSION The incidence of intracranial hemorrhage after spinal surgery was extremely low,with poor clinical outcomes.Patient age,previous stroke history,and dura mater damage were possible risk factors.It is suggested that spinal dura mater injury should be avoided during surgery in high-risk patients.展开更多
The coastal zone of Benin is inherited from the last marine oscillations of the Quaternary. A rich and very fragile environment, it presented until the 1960s, a shoreline in dynamic equilibrium over the entire 125 km ...The coastal zone of Benin is inherited from the last marine oscillations of the Quaternary. A rich and very fragile environment, it presented until the 1960s, a shoreline in dynamic equilibrium over the entire 125 km of coastal line. Since the 1960s, with the construction of important development infrastructures (ports, dams, groins), the Beninese coast is now subject to risks of coastal erosion and seasonal flooding due to the overflow of lagoon water bodies. The present study, based on socio-economic surveys in the communes of Ouidah, Comè and Grand Popo, exposes the extent of coastal risks and socio-economic and environmental damage in the southwestern coastal zone of Benin. The results show that in terms of land, 2.9 ha and 5.7 ha of land have been permanently lost to coastal erosion in the communes of Ouidah and Grand Popo respectively. Similarly, 212 ha of crops of all types were affected by the flooding, including 35 ha destroyed, i.e. 6.67 ha, 11.3 ha in Comè, 4.67 ha Ouidah and 14 ha Grand Popo. Also, 6435 buildings were affected, and 4235 huts were damaged. In addition, working tools, food stocks and other items are counted among the losses recorded by coastal hazards with their corollaries of diseases. The cost of losses and damages in the 08 districts amount to 418,000,000f cfa of which 266,000,000f cfa of damage and 152,000,000f cfa of loss.展开更多
基金supported by the National Key Research and Development Program of China(2021YFC2501800)。
文摘BACKGROUND:Community-acquired bloodstream infections(CABSIs)are common in the emergency departments,and some progress to sepsis and even lead to death.However,limited information is available regarding the prediction of patients with high risk of death.METHODS:The Emergency Bloodstream Infection Score(EBS)for CABSIs was developed to visualize the output of a logistic regression model and was validated by the area under the curve(AUC).The Mortality in Emergency Department Sepsis(MEDS),Pitt Bacteremia Score(PBS),Sequential Organ Failure Assessment(SOFA),quick Sequential Organ Failure Assessment(qSOFA),Charlson Comorbidity Index(CCI),and McCabe–Jackson Comorbid Classification(MJCC)for patients with CABSIs were computed to compare them with EBS in terms of the AUC and decision curve analysis(DCA).The net reclassification improvement(NRI)index and integrated discrimination improvement(IDI)index were compared between the SOFA and EBS.RESULTS:A total of 547 patients with CABSIs were included.The AUC(0.853)of the EBS was larger than those of the MEDS,PBS,SOFA,and qSOFA(all P<0.001).The NRI index of EBS in predicting the in-hospital mortality of CABSIs patients was 0.368(P=0.04),and the IDI index was 0.079(P=0.03).DCA showed that when the threshold probability was<0.1,the net benefit of the EBS model was higher than those of the other models.CONCLUSION:The EBS prognostic models were better than the SOFA,qSOFA,MEDS,and PBS models in predicting the in-hospital mortality of patients with CABSIs.
基金funded by the National Water Special Program of China during 11th Five-Year Plan period(2008ZX07105-002)
文摘This study was designed to find out an optimised planting system of reducing non-point (source) pollution by analyzing the reasons and the factors of influence non-point pollution in farmland of Erhai Lake basin. The results showed that incomes, residual nitrogen in soil, and the loss of nitrogen in surface water in rice-garlic system were higher than those in rice-fava bean system. There were positive correlations between the nitrogen loss of farmland, nitrogen inputs, residual nitrogen in soil, and incomes of farmland. Economic benefits and environment benefits are both appropriate, if the area of rice-garlic system would be reduced to 53% and the area of rice-fava bean system increased to 36% of total cropping area in the investigated watershed. Adjustment of planting structure and introduction of reasonable rotation systems is considered an effective measure of controlling agricultural non-point pollution in watersheds of Erhai Lake.
基金supported in part by the USDA Forest Service, Southern Research Station, through a cooperative research agreement with Joseph Buongiornodirected by Jeff Prestemonsupported in part by the USDA Mc Intire-Stennis fund WVA00105
文摘Background: Forest managers must deal with inherently stochastic ecological and economic processes. The future growth of trees is uncertain, and so is their value. The randomness of low-impact, high frequency or rare catastrophic shocks in forest growth has significant implications in shaping the mix of tree species and the forest landscape. In addition, the fluctuations of wood prices influence greatly forest revenues. Methods: Markov decision process models (MDPs) offer a rigorous and practical way of developing optimum management strategies, given these multiple sources of risk. Results: Examples illustrate how such management guidelines are obtained with MDPs for combined ecological and economic objectives, including diversity of tree species and size, landscape diversity, old growth preservation, and carbon sequestration. Conclusions: The findings illustrate the power of the MDP approach to deal with risk in forest resource management. They recognize that the future is best viewed in terms of probabilities. Given these probabilities, MDPs tie optimum adaptive actions strictly to the state of the forest and timber prices at decision time. The methods are theoretically rigorous, numerically efficient, and practical for field implementation.
文摘In this research, soil samples were collected from Shandong Peninsula Blue Economic Zone to investigate heavy metal pollutions in this region and to evaluate the potential ecological risks of heavy metal pollutants based on Hakanson Potential Ecological Risk Indexes. According to the results, Hg was the primary heavy metal pollutant in Blue Economic Zone, followed by Cd, Cu, and Pb as prevalent pollutants. Heavy metals ranked in order of their pollution degrees are: Hg>Cd>Cu>Pb>Zn>Cr>As;the potential ecological risks of heavy metals follow the order of Hg>Cd>As>Pb>Cu>Cr>Zn. Heavy metal pollutions did exist in this region to a certain extent, and the percentage of potential ecological risk in “strong” and “severe” degree reached up to 13.75%. This composite risk characteristic was subject to the restriction of Hg and Cd mainly distributed in Laizhou-Zhaoyuan- Yantai, Muping-Rushan Goldmine, and other densely-populated regions, threatening the safety production of crops. The combined effects of geological background and human activities, e.g. gold mining and domestic pollutants, were the main causes of high potential ecological risks of heavy metals in local environment.
文摘AIM: To evaluate the association between various lifestyle factors and achalasia risk.METHODS: A population-based case-control study was conducted in Northern Ireland, including n = 151 achalasia cases and n = 117 age- and sexmatched controls. Lifestyle factors were assessed via a face-to-face structured interview. The association between achalasia and lifestyle factors was assessed by unconditional logistic regression, to produce odds ratios(OR) and 95% confidence interval(CI).RESULTS: Individuals who had low-class occupations were at the highest risk of achalasia(OR = 1.88, 95%CI: 1.02-3.45), inferring that high-class occupation holders have a reduced risk of achalasia. A history of foreign travel, a lifestyle factor linked to upper socioeconomic class, was also associated with a reduced risk of achalasia(OR = 0.59, 95%CI: 0.35-0.99). Smoking and alcohol consumption carried significantly reduced risks of achalasia, even after adjustment for socio-economic status. The presence of pets in the house was associated with a two-fold increased risk of achalasia(OR = 2.00, 95%CI: 1.17-3.42). Nochildhood household factors were associated with achalasia risk.CONCLUSION: Achalasia is a disease of inequality, and individuals from low socio-economic backgrounds are at highest risk. This does not appear to be due to corresponding alcohol and smoking behaviours. An observed positive association between pet ownership and achalasia risk suggests an interaction between endotoxin and viral infection exposure in achalasia aetiology.
基金Supported by Fundamental Research Funds for the Central Universities in 2012(2012QT025)Doctoral Dissertation Scholarship Program of China Institute for Rural Studies,Tsinghua University"Study on Food Consumption Level and Structure of Migrant Workers in the Process of Urbanization"(201524)
文摘Based on the precautionary theory,this paper established a framework for consumption of migrant workers from the perspective of the uncertainty risk,and analyzed the effects of uncertain income risk on consumption of migrant workers using the quantile regression method.Results indicated that the income uncertainty significantly inhibits the consumption of migrant workers. The lower the consumption level or the lower the income level,the stronger the inhibitory effect will be. Uncertainty of expenditure also has a significant inhibitory effect on the consumption of migrant workers. Promoting urbanization of migrant workers and accelerating the reform of the household registration system can reduce the uncertainty risks faced by migrant workers,so as to raise the consumption expectation of migrant workers,release the consumption potential of migrant workers,and improve the living standards of migrant workers.
基金sponsored by the Natural Science Foundation of China(NSFC)2018 Emergency Management Project“Exchange Rate Market Variation,Cross-Border Capital Flow and Financial Risk Prevention”(Grant No.71850005)the NSFC Youth Program“Dynamic Estimation of Foreign Exchange Market Pressure in the Process of Capital Account Opening and Evaluation of the Central Bank’s Intervention Policy Effects”(Grant No.71803204).
文摘Based on the global asset portfolio model,this paper created a panel threshold model using EPFR fund data to empirically test the non-linear spillover effects of US economic policy uncertainties on cross-border capital flow for emerging economies.Our study led to the following findings:(1)When the level of global investor risk tolerance is high,rising US EPU will induce a capital inflow into emerging economies,as manifested in the“portfolio rebalancing effect.”When the level of global investor risk tolerance is below a critical threshold,this gives rise to risk aversion and emerging economies will experience net capital outflow,i.e.the“flight to quality effect”.(2)Equity fund investors have a lower risk tolerance threshold than bond fund investors.(3)According to our heterogeneity analysis,more attention should be paid to monitoring capital flow through actively managed funds,ETF funds,and retail investor funds.The economy should increase financial efficiency and economic resiliency to mitigate capital outflow pressures from the external environment.
文摘In 2010, China entered the advanced stage of industrialization, which coincided with the country's entry into a new stage of economic growth. However, this transition is associated with major risks, including adapting to decelerating economic growth. While recognizing the move toward a service-based economy, China must seek to prevent the risk of "manufacturing hollowing out. "' It must also avoid the "technology upgrade trap" while taking advantage of increasingly sophisticated industrial structures. Efforts must also be made to: (1) promote the integration of lT tools and meet risks arising from the New Industrial Revolution; (2) resolve liability risks arising from capacity reduction; and (3) expedite the transition to a functional industrial policy and prevent the failure of a functional industrial policy. In climbing up the global value chain, China must confront the competitive pressures from advanced and emerging economies on both high- and low-end processes of the global value chain.
基金supported by the Key Laboratory of Mountain Hazards and Earth Surface Processes,Chinese Academy of Sciencesthe European Union’s Horizon 2020 research and innovation program Marie Skłodowska-Curie Actions Research and Innovation Staff Exchange (RISE)under grant agreement (Grant No.778360)+1 种基金the National Natural Science Foundation of China (Grant No.51978533)the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No.XDA20030301).
文摘A reliable economic risk map is critical for effective debris-flow mitigation.However,the uncertainties surrounding future scenarios in debris-flow frequency and magnitude restrict its application.To estimate the economic risks caused by future debris flows,a machine learning-based method was proposed to generate an economic risk map by multiplying a debris-flow hazard map and an economic vulnerability map.We selected the Gyirong Zangbo Basin as the study area because frequent severe debris flows impact the area every year.The debris-flow hazard map was developed through the multiplication of the annual probability of spatial impact,temporal probability,and annual susceptibility.We employed a hybrid machine learning model-certainty factor-genetic algorithm-support vector classification-to calculate susceptibilities.Simultaneously,a Poisson model was applied for temporal probabilities,while the determination of annual probability of spatial impact relied on statistical results.Additionally,four major elements at risk were selected for the generation of an economic loss map:roads,vegetation-covered land,residential buildings,and farmland.The economic loss of elements at risk was calculated based on physical vulnerabilities and their economic values.Therefore,we proposed a physical vulnerability matrix for residential buildings,factoring in impact pressure on buildings and their horizontal distance and vertical distance to debrisflow channels.In this context,an ensemble model(XGBoost) was used to predict debris-flow volumes to calculate impact pressures on buildings.The results show that residential buildings occupy 76.7% of the total economic risk,while roadcovered areas contribute approximately 6.85%.Vegetation-covered land and farmland collectively represent 16.45% of the entire risk.These findings can provide a scientific support for the effective mitigation of future debris flows.
基金This research was supported by the National Natural Science Foundation of China(71861008,72063005,U1811462,71532009)the Natural Science Foundation of Hainan Province(718QN221,2019RC151)the Scientific Research Foundation of Hainan University(kyqd(sk)1809,kyqd1634).
文摘This paper investigates the impact of economic policy uncertainty(EPU)on the crash risk of US stock market during the COVID-19 pandemic.To this end,we use the GARCHS(GARCH with skewness)model to estimate daily skewness as a proxy for the stock market crash risk.The empirical results show the significantly negative correlation between EPU and stock market crash risk,indicating the aggravation of EPU increase the crash risk.Moreover,the negative correlation gets stronger after the global COVID-19 outbreak,which shows the crash risk of the US stock market will be more affected by EPU during the epidemic.
基金Projects(51007047,51077087)supported by the National Natural Science Foundation of ChinaProject(2013CB228205)supported by the National Key Basic Research Program of China+1 种基金Project(20100131120039)supported by Higher Learning Doctor Discipline End Scientific Research Fund of the Ministry of Education Institution,ChinaProject(ZR2010EQ035)supported by the Natural Science Foundation of Shandong Province,China
文摘A novel approach was proposed to allocate spinning reserve for dynamic economic dispatch.The proposed approach set up a two-stage stochastic programming model to allocate reserve.The model was solved using a decomposed algorithm based on Benders' decomposition.The model and the algorithm were applied to a simple 3-node system and an actual 445-node system for verification,respectively.Test results show that the model can save 84.5 US $ cost for the testing three-node system,and the algorithm can solve the model for 445-node system within 5 min.The test results also illustrate that the proposed approach is efficient and suitable for large system calculation.
基金from any funding agency in the public,commercial,or not-for-profit sectors.
文摘Online banking fraud occurs whenever a criminal can seize accounts and transfer funds from an individual’s online bank account.Successfully preventing this requires the detection of as many fraudsters as possible,without producing too many false alarms.This is a challenge for machine learning owing to the extremely imbalanced data and complexity of fraud.In addition,classical machine learning methods must be extended,minimizing expected financial losses.Finally,fraud can only be combated systematically and economically if the risks and costs in payment channels are known.We define three models that overcome these challenges:machine learning-based fraud detection,economic optimization of machine learning results,and a risk model to predict the risk of fraud while considering countermeasures.The models were tested utilizing real data.Our machine learning model alone reduces the expected and unexpected losses in the three aggregated payment channels by 15%compared to a benchmark consisting of static if-then rules.Optimizing the machine-learning model further reduces the expected losses by 52%.These results hold with a low false positive rate of 0.4%.Thus,the risk framework of the three models is viable from a business and risk perspective.
基金“Xue Ke Xin Xing”of Beijing Jishuitan Hospital,Beijing,China,No.XKXX201611。
文摘BACKGROUND Intracranial hemorrhage after spinal surgery is a rare and devastating complication.AIM To investigate the economic burden,clinical characteristics,risk factors,and mechanisms of intracranial hemorrhage after spinal surgery.METHODS A retrospective cohort study was conducted from January 1,2015,to December 31,2022.Patients aged≥18 years,who had undergone spinal surgery were included.Intracranial hemorrhage patients were selected after spinal surgery during hospitalization.Based on the type of spinal surgery,patients with intracranial hemorrhage were randomly matched in a 1:5 ratio with control patients without intracranial hemorrhage.The patients'pre-,intra-,and post-operative data and clinical manifestations were recorded.RESULTS A total of 24472 patients underwent spinal surgery.Six patients(3 males and 3 females,average age 71.3 years)developed intracranial hemorrhage after posterior spinal fusion procedures,with an incidence of 0.025%(6/24472).The prevailing type of intracranial hemorrhage was cerebellar hemorrhage.Two patients had a poor clinical outcome.Based on the type of surgery,30 control patients were randomly matched in 1:5 ratio.The intracranial hemorrhage group showed significant differences compared with the control group with regard to age(71.33±7.45 years vs 58.39±8.07 years,P=0.001),previous history of cerebrovascular disease(50%vs 6.7%,P=0.024),spinal dura mater injury(50%vs 3.3%,P=0.010),hospital expenses(RMB 242119.1±87610.0 vs RMB 96290.7±32029.9,P=0.009),and discharge activity daily living score(40.00±25.88 vs 75.40±18.29,P=0.019).CONCLUSION The incidence of intracranial hemorrhage after spinal surgery was extremely low,with poor clinical outcomes.Patient age,previous stroke history,and dura mater damage were possible risk factors.It is suggested that spinal dura mater injury should be avoided during surgery in high-risk patients.
文摘The coastal zone of Benin is inherited from the last marine oscillations of the Quaternary. A rich and very fragile environment, it presented until the 1960s, a shoreline in dynamic equilibrium over the entire 125 km of coastal line. Since the 1960s, with the construction of important development infrastructures (ports, dams, groins), the Beninese coast is now subject to risks of coastal erosion and seasonal flooding due to the overflow of lagoon water bodies. The present study, based on socio-economic surveys in the communes of Ouidah, Comè and Grand Popo, exposes the extent of coastal risks and socio-economic and environmental damage in the southwestern coastal zone of Benin. The results show that in terms of land, 2.9 ha and 5.7 ha of land have been permanently lost to coastal erosion in the communes of Ouidah and Grand Popo respectively. Similarly, 212 ha of crops of all types were affected by the flooding, including 35 ha destroyed, i.e. 6.67 ha, 11.3 ha in Comè, 4.67 ha Ouidah and 14 ha Grand Popo. Also, 6435 buildings were affected, and 4235 huts were damaged. In addition, working tools, food stocks and other items are counted among the losses recorded by coastal hazards with their corollaries of diseases. The cost of losses and damages in the 08 districts amount to 418,000,000f cfa of which 266,000,000f cfa of damage and 152,000,000f cfa of loss.