Timely and reliable estimation of regional crop yield is a vital component of food security assessment, especially in developing regions. The traditional crop forecasting methods need ample time and labor to collect a...Timely and reliable estimation of regional crop yield is a vital component of food security assessment, especially in developing regions. The traditional crop forecasting methods need ample time and labor to collect and process field data to release official yield reports. Satellite remote sensing data is considered a cost-effective and accurate way of predicting crop yield at pixel-level. In this study, maximum Enhanced Vegetation Index (EVI) during the crop-growing season was integrated with Machine Learning Regression (MLR) models to estimate wheat and rice yields in Pakistan’s Punjab province. Five MLR models were compared using a fivefold cross-validation method for their predictive accuracy. The study results revealed that the regression model based on the Gaussian process outperformed over other models. The best performing model attained coefficient of determination (R^(2)), Root Mean Square Error (RMSE, t/ ha), and Mean Absolute Error (MAE, t/ha) of 0.75, 0.281, and 0.236 for wheat;0.68, 0.112, and 0.091 for rice, respectively. The proposed method made it feasible to predict wheat and rice 6- 8 weeks before the harvest. The early prediction of crop yield and its spatial distribution in the region can help formulate efficient agricultural policies for sustainable social, environmental, and economic progress.展开更多
Quorum systems have been used to solve the problem of data consistency in distributed fault-tolerance systems.But when intrusions occur,traditional quorum systems have some disadvantages.For example,synchronous quorum...Quorum systems have been used to solve the problem of data consistency in distributed fault-tolerance systems.But when intrusions occur,traditional quorum systems have some disadvantages.For example,synchronous quorum systems are subject to DOS attacks,while asynchronous quorum systems need a larger system size(at least 3f+1 for generic data,and f fewer for self-verifying data).In order to solve the problems above,an intrusion-tolerance quorum system(ITQS)of hybrid time model based on trust timely computing base is presented(TTCB).The TTCB is a trust secure real-time component inside the server with a well defined interface and separated from the operation system.It is in the synchronous communication environment while the application layer in the server deals with read-write requests and executes update-copy protocols asynchronously.The architectural hybridization of synchrony and asynchrony can achieve the data consistency and availability correctly.We also build two kinds of ITQSes based on TTCB,i.e.,the symmetrical and the asymmetrical TTCB quorum systems.In the performance evaluations,we show that TTCB quorum systems are of smaller size,lower load and higher availability.展开更多
Background: Ensuring prompt diagnosis and timely malaria treatment will prevent most cases of uncomplicated malaria from progressing to severe and fatal illness. To avoid this progression, treatment must begin as soon...Background: Ensuring prompt diagnosis and timely malaria treatment will prevent most cases of uncomplicated malaria from progressing to severe and fatal illness. To avoid this progression, treatment must begin as soon as possible, generally within 24 hours after symptoms onset. The reason why mothers/caretakers delay in malaria prompt diagnosis and timely treatment for under-five is not well studied in the study area as well as in Ethiopia. Objective: To assess determinants of delay in malaria prompt diagnosis and timely treatment among under-five children in Shashogo Woreda, Hadiya Zone, Southern Ethiopia, 2013. Methods: An unmatched case control study was conducted from March 25-April 25, 2013. A total sample size of 302 with 151 cases and 151 controls were selected by systematic random sampling techniques. Cases were under-five children who had clinical malaria and sought treatment after 24 hours of symptoms onset, and controls were under-five children who had clinical malaria and sought treatment within 24 hours of symptoms onset. Both bivariate and multivariate logistic regressions were done to identify determinant of delay in malaria prompt diagnosis and timely treatment. Results: A total of 151 mothers/caretakers of cases and 151 mothers/caretakers of controls were interviewed. Illiterate mothers (AOR = 7.14;95%CI: 1.10, 46.39), monthly income ≤500 ETB (AOR = 5.49;95%CI: 2.09, 14.45), females sex (AOR = 3.45;95%CI: 1.62, 7.34), distance from health facility >5 km (AOR = 4.31;95%CI: 1.22, 15.23), absence of history of child death (AOR = 4.21;95%CI: 1.514, 11.68), side effects of antimalarial drugs (AOR = 2.91;95%CI: 1.15, 7.33) and khat chewing (AOR = 2.38;95%CI: 1.28, 5.79) were determinants of delay in malaria prompt diagnosis and timely treatment of under-five children. Conclusion: Mother’s education, monthly income, distance from health facility, absence of history of child death, complained about side effects of drugs and khat chewing were predictors of delay of prompt diagnosis and timely malaria treatment. Effective malaria control programs revision would be required to avoid delay of prompt diagnosis and timely treatment for under-five children.展开更多
In recent years,significant breakthroughs have been achieved in the exploration of deep volcanic rocks in the Junggar Basin,highlighting their substantial exploration potential.The complex distribution of volcanic res...In recent years,significant breakthroughs have been achieved in the exploration of deep volcanic rocks in the Junggar Basin,highlighting their substantial exploration potential.The complex distribution of volcanic reservoirs is attributed to the multi-phase tectonic evolution within the basin,with their superior reservoir properties playing a crucial role in natural gas formation.However,due to the combined effects of multi-cyclic volcanic eruptions and tectonic activities,predicting volcanic facies distribution and favorable reservoirs remains highly challenging.This study focuses on the third member of the Jiamuhe Formation in the Zhongguai Uplift.By integrating drilling and petrophysical data with well-seismic analysis techniques,a seismic identification model for volcanic reservoirs has been established.The findings reveal that different facies exhibit distinct seismic response characteristics.Andesite,rhyolite,volcanic breccia,and volcanic clastic rocks show variability in amplitude,frequency,and continuity.Using structural-guided filtering,high-resolution coherence analysis,and 3D body carving techniques,the locations of volcanic craters and eruption centers were successfully identified,further clarifying the distribution patterns of volcanic facies.By combining multi-attribute clustering analysis and seismic attribute extraction,a volcanic facies zone distribution map was generated,and favorable exploration directions for volcanic reservoirs were proposed.The study provides technical guidance for the exploration of deep volcanic oil and gas reservoirs in the Junggar Basin and holds significant application value.展开更多
Ideally,firms should discontinue projects that become unprofitable.Managers,however,continue to operate such projects because of their limited employment horizons and empire-building motivations(Jensen,1986; Ball,2001...Ideally,firms should discontinue projects that become unprofitable.Managers,however,continue to operate such projects because of their limited employment horizons and empire-building motivations(Jensen,1986; Ball,2001).Prior studies suggest that timely loss recognition in accounting earnings enables lenders,shareholders,and boards of directors to identify unprofitable projects; thereby,enabling them to force managers to discontinue such projects before large value erosion occurs.However,this conjecture has not been tested empirically.Consistent with this notion,we find that timely loss recognition increases the likelihood of timely closures of unprofitable projects.Moreover,managers,by announcing late discontinuations of such projects,reveal their inability to select good projects and/or to contain losses,when projects turn unprofitable.Accordingly,thereafter,the fund providers and board of directors are likely to demand improved timeliness of loss recognition and stringent scrutiny of firms' capital expenditure plans.Consistently,we find that firms that announce large discontinuation losses reduce capital expenditures and improve timeliness of loss recognition in subsequent years.Our study provides evidence that timely loss reporting affects "real" economic decisions and creates economic benefits.展开更多
After spinal cord injury,impairment of the sensorimotor circuit can lead to dysfunction in the motor,sensory,proprioceptive,and autonomic nervous systems.Functional recovery is often hindered by constraints on the tim...After spinal cord injury,impairment of the sensorimotor circuit can lead to dysfunction in the motor,sensory,proprioceptive,and autonomic nervous systems.Functional recovery is often hindered by constraints on the timing of interventions,combined with the limitations of current methods.To address these challenges,various techniques have been developed to aid in the repair and reconstruction of neural circuits at different stages of injury.Notably,neuromodulation has garnered considerable attention for its potential to enhance nerve regeneration,provide neuroprotection,restore neurons,and regulate the neural reorganization of circuits within the cerebral cortex and corticospinal tract.To improve the effectiveness of these interventions,the implementation of multitarget early interventional neuromodulation strategies,such as electrical and magnetic stimulation,is recommended to enhance functional recovery across different phases of nerve injury.This review concisely outlines the challenges encountered following spinal cord injury,synthesizes existing neurostimulation techniques while emphasizing neuroprotection,repair,and regeneration of impaired connections,and advocates for multi-targeted,task-oriented,and timely interventions.展开更多
体例要求1.注释采用脚注、每页排序方式,编号加圈,逐一注明文中引用或参考的资料数据出处。2.中文注释采用宋体小五号,外文注释采用Times New Roman小五号。3.英文注释中的著作和文章名首字母大写,动词、名词、形容词等实词首字母大写,...体例要求1.注释采用脚注、每页排序方式,编号加圈,逐一注明文中引用或参考的资料数据出处。2.中文注释采用宋体小五号,外文注释采用Times New Roman小五号。3.英文注释中的著作和文章名首字母大写,动词、名词、形容词等实词首字母大写,介词、连词、冠词字母小写。4.网络材料应是研究机构、国际组织/机构、行业或专业组织/机构、政府等官方网站的权威材料,并须标注投稿时能够访问的有效网址。展开更多
This study investigates prescribed-time position tracking control for electromagnetic satellite formations subject to model uncertainties and external disturbances.Using the Clohessy-Wiltshire equations as the relativ...This study investigates prescribed-time position tracking control for electromagnetic satellite formations subject to model uncertainties and external disturbances.Using the Clohessy-Wiltshire equations as the relative motion dynamics model,a prescribed time output feedback control strategy is proposed.A prescribed-time extended state observer is designed to estimate the relative velocity and external disturbances.The disturbance estimates are then used as the feedforward component of the controller.Building on this framework,a novel prescribed-time active disturbance rejection control strategy for position tracking is developed via a backstepping control design.The convergence of the extended state observer and the stability of the closed-loop system are rigorously analyzed using Lyapunov stability theory.Numerical simulations are performed to validate the effectiveness of the proposed controller.展开更多
A series of blue and blue‑green Ir(Ⅲ)complexes has been investigated theoretically to explore their electronic structures,photophysical properties,efficiency roll‑off effect,and thermal activation delayed fluorescenc...A series of blue and blue‑green Ir(Ⅲ)complexes has been investigated theoretically to explore their electronic structures,photophysical properties,efficiency roll‑off effect,and thermal activation delayed fluorescence(TADF)properties.All calculations were performed using density functional theory(DFT)and time‑dependent density functional theory(TDDFT).Calculations for electronic structures,frontier molecular orbital characteristics(which determine the efficiency roll‑off effect of the complexes),and photophysical properties were conducted using the Gaussian 09 software package.The calculation of spin‑orbit coupling matrix elements<T|HSOC|S>,which determine the TADF properties of the complexes,was performed using the ORCA software package.The calculation results show that the auxiliary ligand tetraphenylimidodiphosphinate(tpip),a strong electron‑withdrawing group,can mitigate the efficiency roll‑off effect of the complex.Furthermore,TADF is observed in one of the designed complexes,(F_(3)Phppy)_(2)Ir(tpip),where F_(3)Phppy=2‑[4‑(2,4,6‑trifluorophenyl)phenyl]pyridine.展开更多
Background:Early control of haemorrhage and optimisation of physiology are guiding principles of resuscitation after injury.Improved outcomes have been previously associated with single,timely interventions.The aim of...Background:Early control of haemorrhage and optimisation of physiology are guiding principles of resuscitation after injury.Improved outcomes have been previously associated with single,timely interventions.The aim of this study was to assess the association between multiple timely life-saving interventions(LSIs)and outcomes of traumatic haemorrhagic shock patients.Methods:A retrospective cohort study was undertaken of injured patients with haemorrhagic shock who presented to Alfered Emergency&Trauma Centre between July 01,2010 and July 31,2014.LSIs studied included chest decompression,control of external haemorrhage,pelvic binder application,transfusion of red cells and coagulation products and surgical control of bleeding through angio-embolisation or operative intervention.The primary exposure variable was timely initiation of≥50%of the indicated interventions.The association between the primary exposure variable and outcome of death at hospital discharge was adjusted for potential confounders using multivariable logistic regression analysis.The association between total pre-hospital times and pre-hospital care times(time from ambulance at scene to trauma centre),in-hospital mortality and timely initiation of≥50%of the indicated interventions were assessed.Results:Of the 168 patients,54(32.1%)patients had≥50%of indicated LSI completed within the specified time period.Timely delivery of LSI was independently associated with improved survival to hospital discharge(adjusted odds ratio(OR)for in-hospital death 0.17;95%confidence interval(CI)0.03–0.83;p=0.028).This association was independent of patient age,pre-hospital care time,injury severity score,initial serum lactate levels and coagulopathy.Among patients with pre-hospital time of≥2 h,2(3.6%)received timely LSIs.Pre-hospital care times of≥2 h were associated with delayed LSIs and with in-hospital death(unadjusted OR 4.3;95%CI 1.4–13.0).Conclusions:Timely completion of LSI when indicated was completed in a small proportion of patients and reflects previous research demonstrating delayed processes and errors even in advanced trauma systems.Timely delivery of a high proportion of LSIs was associated with improved outcomes among patients presenting with haemorrhagic shock after injury.Provision of LSIs in the pre-hospital phase of trauma care has the potential to improve outcomes.展开更多
AIM:To compare the tear film quantity and stability parameters in keratoconus(KCN)and normal eyes using test breakup time(TBUT),noninvasive TBUT(NITBUT),and Schirmer test.METHODS:All participants(n=166),including pati...AIM:To compare the tear film quantity and stability parameters in keratoconus(KCN)and normal eyes using test breakup time(TBUT),noninvasive TBUT(NITBUT),and Schirmer test.METHODS:All participants(n=166),including patients with KCN and age-matched healthy individuals with normal corneas,were recruited from those referred to Farabi Eye Hospital,Iran,in 2023.To better account for genetic and environmental factors,the control group comprised healthy individuals who were relatives of KCN patients and had normal corneal topography.Tear quantity parameters were evaluated in the following order:NITBUT,TBUT,and Schirmer tests.RESULTS:The mean age of cases in KCN(61.7%males)and normal(63.5%males)participants was 27.54±5.44y(range 19 to 38)and 27.52±5.63y(range 20 to 38),respectively(P=0.976).NIBUT,TBUT,and Schirmer’s tests were significantly lower in KCN group compared to normal controls(all P<0.001).The mean difference for NIBUT was-7.81s(P<0.001),and for TBUT was-7.61s(P<0.001).Schirmer test values were also significantly lower in the KCN group,with a mean difference of-5.61 mm compared to normal people(P<0.001).CONCLUSION:Our findings demonstrate significant tear film impairment in KCN.The reductions in NIBUT,TBUT and Schirmer scores highlight an underlying tear film dysfunction in KCN that extends beyond the morphological changes of the cornea.展开更多
Drought influences carbon fixation by plants.Therefore,elucidating its impact on carbon fluxes in plants at the ecosystem level is crucial for assessing their role in mitigating climate change.Using carbon fluxes and ...Drought influences carbon fixation by plants.Therefore,elucidating its impact on carbon fluxes in plants at the ecosystem level is crucial for assessing their role in mitigating climate change.Using carbon fluxes and environmental factor data from FLUXNET sites,we analyzed the influence of drought on carbon fluxes,their drivers,time-lag effects,and recovery times across various climatic regions and seasons.Results showed drought significantly decreased gross primary production(GPP),ecosystem respiration,and net ecosystem productivity in arid regions but slightly increased carbon sequestration in humid regions.Summer droughts negatively affected vegetation carbon fluxes,partly offset by the positive impact of spring droughts.Nonforest carbon fluxes were more susceptible to drought effects than forest fluxes.Soil water content(SWC)was the main influence on changes in arid regions,whereas vapor pressure deficit(VPD)dominated humid regions.Decreased SWC and increased VPD reduced carbon sequestration in arid regions but increased it in humid regions.Increased VPD reduced GPP,leading to forest carbon loss,whereas decreased SWC reduced GPP,leading to nonforest carbon loss.The lag time of the drought effects on carbon fluxes was longer in humid regions(19.44 d)than in arid regions(14.71 d).Compared to nonforest areas(16.74 d and 57 d for drought lag and recovery time,respectively),forest areas had a longer lag(18.81 d)and recovery time(92 d).The findings revealed discrepancies in the main factors regulating vegetation carbon fluxes during droughts between arid and humid regions and between forest and nonforest ecosystems.These insights provide a new perspective on understanding and simulating carbon-climate feedback.Enhancing ecosystem diversity is a feasible measure to increase drought resistance.展开更多
Overseas investors are enthusiastic about the Chinese stock market as the equities are attractively priced and investors can expect profitable returns in the long「un. This is the verdict of Mark Makepeace, head of FT...Overseas investors are enthusiastic about the Chinese stock market as the equities are attractively priced and investors can expect profitable returns in the long「un. This is the verdict of Mark Makepeace, head of FTSE Russell, the second largest index provider in the world, whose organization will include Chinese shares in its major benchmarks.展开更多
Chilo suppressalis(Walker)is one of the most important rice pests worldwide,posing a significant challenge to effective control.To develop a precision-timed,eco-friendly management strategy,overwintering population in...Chilo suppressalis(Walker)is one of the most important rice pests worldwide,posing a significant challenge to effective control.To develop a precision-timed,eco-friendly management strategy,overwintering population investigation and dynamic monitoring of C.suppressalis populations were conducted in the Meishan region of Sichuan,China,from 2023 to 2024.The optimal timing for insecticide application was estimated,followed by field trials evaluating the efficacy of different insecticides.Results demonstrated that the peak emergence of first-generation adults typically occurred in early July(under the environmental conditions of the Meishan region),with the ambient humidity below 75%and temperature around 29◦C.Pesticide efficacy trials show that insecticide combinations exhibited superior control.Notably,a combined treatment of emamectin benzoate⋅methoxyfenozide+chlorantraniliprole achieved the highest control efficacy(90.05%)and a corresponding yield of 12,491.55 kg/ha.All tested treatments were determined to be safe for rice growth.Furthermore,this optimized strategy resulted in notable economic benefits,including a 50%reduction in pesticide usage and cost savings of 4796.15 CNY compared to conventional practices.This study provides valuable insights into sustainable rice production and pest management and,for the first time,proposes a precision application time window based on intelligent monitoring.展开更多
To address the key scientific challenge of monitoring the dynamic fracturing of surrounding rock in deep roadways,this study systematically investigates the quantitative relationship between stress and charge signals ...To address the key scientific challenge of monitoring the dynamic fracturing of surrounding rock in deep roadways,this study systematically investigates the quantitative relationship between stress and charge signals during coal mass loading.By integrating innovative analytical approaches,introducing quantitative evaluation indices,and developing a charge–stress inversion model,and incorporating underground monitoring practices,significant progress has been achieved in elucidating the correlation between stress variations and charge signals throughout the entire coal mass fracturing process.First,in the field of stress–charge correlation analysis,empirical mode decomposition(EMD)was combined with wavelet coherence analysis for the first time,enabling the removal of slow-varying stress trends while retaining high-frequency fluctuations.This approach allowed for the quantitative characterization of the evolution of coherence between stress variations and charge fluctuations across multiple time scales.Second,coherence skewness and the proportion of high-coherence intervals were innovatively introduced to examine the influence of time scale selection on correlation results.On this basis,a criterion for determining the near-optimal observation scale of charge signals was proposed,providing a quantitative reference for time scale selection in similar signal analyses.Finally,by correlating charge signals with coal damage factors and stress states,a charge-based damage evolution equation was established to achieve effective stress inversion.Combined with in situ monitoring of stress and charge in roadway surrounding rock,this approach revealed the correlation characteristics of stress and charge intensity responses during the dynamic fracturing process.The results indicate,first,that charge signals are not significantly correlated with the absolute stress level of coal but are directly associated with stress variations following coal damage and failure,with the amplitude of charge fluctuations increasing alongside stress fluctuations.Second,coherence between stress and charge signals varies markedly across time scales,with excessively small or large scales leading to distortion,and the scale corresponding to the peak proportion of intervals with coherence>0.8 was identified as the near-optimal observation scale.Third,charge signals can effectively characterize coal damage factors,and the established damage evolution equation can effectively invert stress variation trends.Fourth,in underground roadways,zones of dynamic fracturing in surrounding rock are commonly located in areas where stress concentration overlaps with regions of high charge intensity,further confirming the strong consistency between charge and stress variations.These findings improve the theoretical framework of charge signal responses in loaded coal and provide a scientific basis for precise“stress-charge”monitoring of dynamic disasters,offering practical potential for engineering applications.展开更多
Flowering time is a critical agronomic trait with a profound effect on the productivity and adaptabillity of rapeseed(Brassica napus L.).Strategically advancing flowering time can reduce the risk of yield losses due t...Flowering time is a critical agronomic trait with a profound effect on the productivity and adaptabillity of rapeseed(Brassica napus L.).Strategically advancing flowering time can reduce the risk of yield losses due to extreme climatic conditions and facilitate the cultivation of subsequent crops on the same land,thereby enhancing overall agricultural efficiency.In this review,we synthesize current information on flowering time regulation in rapeseed through an integrated analysis of its genetic,hormonal,and environmental dimensions,emphasizing their crosstalk and implications for yield.We consolidate multi-omics evidence from population genetics,functional genomics,and systems biology to create a haplotype-based framework that overcomes the trade-off between flowering time and yield,providing support for the precision breeding of early-maturing cultivars.The insights presented here could inform future research on flowering time regulation and guide strategies for increasing rapeseed productivity.展开更多
This research is focused on the calculation of a reasonable detonator delay time for realizing cut blast vibration control.First,the viscoelastic rock mass parameters corresponding to the engineering rock mass quality...This research is focused on the calculation of a reasonable detonator delay time for realizing cut blast vibration control.First,the viscoelastic rock mass parameters corresponding to the engineering rock mass quality classification were determined based on wave theory of Kelvin medium.Then,a calculation model was obtained for the millisecond-delay cut blast vibration in Kelvin media using the Starfield charge superposition principle.Further,the influence of the delay time on the cut blast vibration was quantitatively analyzed and a method for calculating the reasonable cut blasting millisecond delay time is proposed according to the principle of dimensional analysis.Finally,field tests were used to verify the applicability of the method.The results show that 5 ms to 20 ms is a better detonator delay time range and cut blasting vibration can be effectively controlled using the delay time calculated by the calculation model described in this paper.展开更多
The Shanghai High Repetition Rate XFEL and Extreme Light Facility(SHINE)is currently under construction as one of the world’s most advanced hard X-ray free-electron laser facilities.The timing system,as an essential ...The Shanghai High Repetition Rate XFEL and Extreme Light Facility(SHINE)is currently under construction as one of the world’s most advanced hard X-ray free-electron laser facilities.The timing system,as an essential part of the free-electron laser facility,provides precise timing of trigger pulse signals for a range of devices to ensure that particles are generated and accelerated to the designed energy while enabling the precise measurement of beam parameters.To precisely distribute and synchronize the 1.003086 MHz(1300/1296)timing signals over a distance of approximately 3.1 km based on White Rabbit technology,three technical routes have been proposed.This paper begins with a description of the design and development process of the timing system for the SHINE project,which culminates with the determination of the design scheme.During the installation and commissioning of the timing system,the jitter accuracy of the timing signal was tested and found to be less than 10 ps,which meets the requirements of the project.Furthermore,the precise clock synchronization signal provided by the timing system supported the joint debugging of various related systems and realization of beam acquisition.展开更多
Peri-urban plantations in the Mediterranean are often degraded due to human inactivity and climate change,leading to a loss of ecosystem services and biodiversity.This study investigates the impact of different thinni...Peri-urban plantations in the Mediterranean are often degraded due to human inactivity and climate change,leading to a loss of ecosystem services and biodiversity.This study investigates the impact of different thinning practices on carbon sequestration and tree stability in a degraded periurban plantation in the Italian Apennines,six years after thinning.Three treatments were compared:(a)moderate thinning from below(-25%biomass),representing the typical practice;(b)intense selective thinning(-35%biomass),representing an innovative approach;and(c)no management as the control.Growth projections were used to estimate carbon recovery for these treatments,based on site-specific models calibrated with real data.The results show that both thinning approaches increased carbon sequestration over time,with the innovative thinning achieving a 7%higher annual carbon sequestration rate than traditional thinning and 8%more than the control.Estimated payback times were9 years for recovering the harvested volume in both thinning approaches,10 years for innovative thinning to surpass traditional thinning,17 years for innovative thinning to surpass the control,and 24 years for traditional thinning to surpass the control.Additionally,tree mechanical stability improved significantly in both thinning treatments after two years,with further increases observed in the innovative thinning group after six years.These results suggest that selective thinning can accelerate forest recovery and carbon sequestration,especially in areas with high stem density,where it can reduce the negative impacts of tree mortality and deadwood accumulation.However,careful planning is required to mitigate potential short-term stability is sues,particularly in challenging environments(e.g.,windy conditions,steep slopes).Forest management strategies should therefore aim to balance growth,carbon storage,and tree stability,considering both long-term sustainability and local environmental conditions.The findings are particularly relevant for current climate change mitigation strategies,emphasizing that thinning should be carefully tailored to forest type and conditions to maximize benefits in carbon credit generation and sustainable forest management practices.展开更多
基金The research is supported by the Natural Science Foundation of China(NSFC)General Research(Grant number 41971386)Hong Kong Research Grant Council(RGC)General Research Fund(Grant number 12301820)+2 种基金The work is a part of PhD research funded by Hong Kong PhD Fellowship Scheme(HKPFS)Natural Science Foundation of China(NSFC)General Program(Grant number 41971386)Hong Kong Research Grant Council(RGC)General Research Fund(Grant number 12301820).
文摘Timely and reliable estimation of regional crop yield is a vital component of food security assessment, especially in developing regions. The traditional crop forecasting methods need ample time and labor to collect and process field data to release official yield reports. Satellite remote sensing data is considered a cost-effective and accurate way of predicting crop yield at pixel-level. In this study, maximum Enhanced Vegetation Index (EVI) during the crop-growing season was integrated with Machine Learning Regression (MLR) models to estimate wheat and rice yields in Pakistan’s Punjab province. Five MLR models were compared using a fivefold cross-validation method for their predictive accuracy. The study results revealed that the regression model based on the Gaussian process outperformed over other models. The best performing model attained coefficient of determination (R^(2)), Root Mean Square Error (RMSE, t/ ha), and Mean Absolute Error (MAE, t/ha) of 0.75, 0.281, and 0.236 for wheat;0.68, 0.112, and 0.091 for rice, respectively. The proposed method made it feasible to predict wheat and rice 6- 8 weeks before the harvest. The early prediction of crop yield and its spatial distribution in the region can help formulate efficient agricultural policies for sustainable social, environmental, and economic progress.
基金supported by the National Natural Science Foundation of China(60774091)
文摘Quorum systems have been used to solve the problem of data consistency in distributed fault-tolerance systems.But when intrusions occur,traditional quorum systems have some disadvantages.For example,synchronous quorum systems are subject to DOS attacks,while asynchronous quorum systems need a larger system size(at least 3f+1 for generic data,and f fewer for self-verifying data).In order to solve the problems above,an intrusion-tolerance quorum system(ITQS)of hybrid time model based on trust timely computing base is presented(TTCB).The TTCB is a trust secure real-time component inside the server with a well defined interface and separated from the operation system.It is in the synchronous communication environment while the application layer in the server deals with read-write requests and executes update-copy protocols asynchronously.The architectural hybridization of synchrony and asynchrony can achieve the data consistency and availability correctly.We also build two kinds of ITQSes based on TTCB,i.e.,the symmetrical and the asymmetrical TTCB quorum systems.In the performance evaluations,we show that TTCB quorum systems are of smaller size,lower load and higher availability.
文摘Background: Ensuring prompt diagnosis and timely malaria treatment will prevent most cases of uncomplicated malaria from progressing to severe and fatal illness. To avoid this progression, treatment must begin as soon as possible, generally within 24 hours after symptoms onset. The reason why mothers/caretakers delay in malaria prompt diagnosis and timely treatment for under-five is not well studied in the study area as well as in Ethiopia. Objective: To assess determinants of delay in malaria prompt diagnosis and timely treatment among under-five children in Shashogo Woreda, Hadiya Zone, Southern Ethiopia, 2013. Methods: An unmatched case control study was conducted from March 25-April 25, 2013. A total sample size of 302 with 151 cases and 151 controls were selected by systematic random sampling techniques. Cases were under-five children who had clinical malaria and sought treatment after 24 hours of symptoms onset, and controls were under-five children who had clinical malaria and sought treatment within 24 hours of symptoms onset. Both bivariate and multivariate logistic regressions were done to identify determinant of delay in malaria prompt diagnosis and timely treatment. Results: A total of 151 mothers/caretakers of cases and 151 mothers/caretakers of controls were interviewed. Illiterate mothers (AOR = 7.14;95%CI: 1.10, 46.39), monthly income ≤500 ETB (AOR = 5.49;95%CI: 2.09, 14.45), females sex (AOR = 3.45;95%CI: 1.62, 7.34), distance from health facility >5 km (AOR = 4.31;95%CI: 1.22, 15.23), absence of history of child death (AOR = 4.21;95%CI: 1.514, 11.68), side effects of antimalarial drugs (AOR = 2.91;95%CI: 1.15, 7.33) and khat chewing (AOR = 2.38;95%CI: 1.28, 5.79) were determinants of delay in malaria prompt diagnosis and timely treatment of under-five children. Conclusion: Mother’s education, monthly income, distance from health facility, absence of history of child death, complained about side effects of drugs and khat chewing were predictors of delay of prompt diagnosis and timely malaria treatment. Effective malaria control programs revision would be required to avoid delay of prompt diagnosis and timely treatment for under-five children.
文摘In recent years,significant breakthroughs have been achieved in the exploration of deep volcanic rocks in the Junggar Basin,highlighting their substantial exploration potential.The complex distribution of volcanic reservoirs is attributed to the multi-phase tectonic evolution within the basin,with their superior reservoir properties playing a crucial role in natural gas formation.However,due to the combined effects of multi-cyclic volcanic eruptions and tectonic activities,predicting volcanic facies distribution and favorable reservoirs remains highly challenging.This study focuses on the third member of the Jiamuhe Formation in the Zhongguai Uplift.By integrating drilling and petrophysical data with well-seismic analysis techniques,a seismic identification model for volcanic reservoirs has been established.The findings reveal that different facies exhibit distinct seismic response characteristics.Andesite,rhyolite,volcanic breccia,and volcanic clastic rocks show variability in amplitude,frequency,and continuity.Using structural-guided filtering,high-resolution coherence analysis,and 3D body carving techniques,the locations of volcanic craters and eruption centers were successfully identified,further clarifying the distribution patterns of volcanic facies.By combining multi-attribute clustering analysis and seismic attribute extraction,a volcanic facies zone distribution map was generated,and favorable exploration directions for volcanic reservoirs were proposed.The study provides technical guidance for the exploration of deep volcanic oil and gas reservoirs in the Junggar Basin and holds significant application value.
文摘Ideally,firms should discontinue projects that become unprofitable.Managers,however,continue to operate such projects because of their limited employment horizons and empire-building motivations(Jensen,1986; Ball,2001).Prior studies suggest that timely loss recognition in accounting earnings enables lenders,shareholders,and boards of directors to identify unprofitable projects; thereby,enabling them to force managers to discontinue such projects before large value erosion occurs.However,this conjecture has not been tested empirically.Consistent with this notion,we find that timely loss recognition increases the likelihood of timely closures of unprofitable projects.Moreover,managers,by announcing late discontinuations of such projects,reveal their inability to select good projects and/or to contain losses,when projects turn unprofitable.Accordingly,thereafter,the fund providers and board of directors are likely to demand improved timeliness of loss recognition and stringent scrutiny of firms' capital expenditure plans.Consistently,we find that firms that announce large discontinuation losses reduce capital expenditures and improve timeliness of loss recognition in subsequent years.Our study provides evidence that timely loss reporting affects "real" economic decisions and creates economic benefits.
基金supported by the National Key Research and Development Program of China,No.2023YFC3603705(to DX)the National Natural Science Foundation of China,No.82302866(to YZ).
文摘After spinal cord injury,impairment of the sensorimotor circuit can lead to dysfunction in the motor,sensory,proprioceptive,and autonomic nervous systems.Functional recovery is often hindered by constraints on the timing of interventions,combined with the limitations of current methods.To address these challenges,various techniques have been developed to aid in the repair and reconstruction of neural circuits at different stages of injury.Notably,neuromodulation has garnered considerable attention for its potential to enhance nerve regeneration,provide neuroprotection,restore neurons,and regulate the neural reorganization of circuits within the cerebral cortex and corticospinal tract.To improve the effectiveness of these interventions,the implementation of multitarget early interventional neuromodulation strategies,such as electrical and magnetic stimulation,is recommended to enhance functional recovery across different phases of nerve injury.This review concisely outlines the challenges encountered following spinal cord injury,synthesizes existing neurostimulation techniques while emphasizing neuroprotection,repair,and regeneration of impaired connections,and advocates for multi-targeted,task-oriented,and timely interventions.
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文摘This study investigates prescribed-time position tracking control for electromagnetic satellite formations subject to model uncertainties and external disturbances.Using the Clohessy-Wiltshire equations as the relative motion dynamics model,a prescribed time output feedback control strategy is proposed.A prescribed-time extended state observer is designed to estimate the relative velocity and external disturbances.The disturbance estimates are then used as the feedforward component of the controller.Building on this framework,a novel prescribed-time active disturbance rejection control strategy for position tracking is developed via a backstepping control design.The convergence of the extended state observer and the stability of the closed-loop system are rigorously analyzed using Lyapunov stability theory.Numerical simulations are performed to validate the effectiveness of the proposed controller.
文摘A series of blue and blue‑green Ir(Ⅲ)complexes has been investigated theoretically to explore their electronic structures,photophysical properties,efficiency roll‑off effect,and thermal activation delayed fluorescence(TADF)properties.All calculations were performed using density functional theory(DFT)and time‑dependent density functional theory(TDDFT).Calculations for electronic structures,frontier molecular orbital characteristics(which determine the efficiency roll‑off effect of the complexes),and photophysical properties were conducted using the Gaussian 09 software package.The calculation of spin‑orbit coupling matrix elements<T|HSOC|S>,which determine the TADF properties of the complexes,was performed using the ORCA software package.The calculation results show that the auxiliary ligand tetraphenylimidodiphosphinate(tpip),a strong electron‑withdrawing group,can mitigate the efficiency roll‑off effect of the complex.Furthermore,TADF is observed in one of the designed complexes,(F_(3)Phppy)_(2)Ir(tpip),where F_(3)Phppy=2‑[4‑(2,4,6‑trifluorophenyl)phenyl]pyridine.
文摘Background:Early control of haemorrhage and optimisation of physiology are guiding principles of resuscitation after injury.Improved outcomes have been previously associated with single,timely interventions.The aim of this study was to assess the association between multiple timely life-saving interventions(LSIs)and outcomes of traumatic haemorrhagic shock patients.Methods:A retrospective cohort study was undertaken of injured patients with haemorrhagic shock who presented to Alfered Emergency&Trauma Centre between July 01,2010 and July 31,2014.LSIs studied included chest decompression,control of external haemorrhage,pelvic binder application,transfusion of red cells and coagulation products and surgical control of bleeding through angio-embolisation or operative intervention.The primary exposure variable was timely initiation of≥50%of the indicated interventions.The association between the primary exposure variable and outcome of death at hospital discharge was adjusted for potential confounders using multivariable logistic regression analysis.The association between total pre-hospital times and pre-hospital care times(time from ambulance at scene to trauma centre),in-hospital mortality and timely initiation of≥50%of the indicated interventions were assessed.Results:Of the 168 patients,54(32.1%)patients had≥50%of indicated LSI completed within the specified time period.Timely delivery of LSI was independently associated with improved survival to hospital discharge(adjusted odds ratio(OR)for in-hospital death 0.17;95%confidence interval(CI)0.03–0.83;p=0.028).This association was independent of patient age,pre-hospital care time,injury severity score,initial serum lactate levels and coagulopathy.Among patients with pre-hospital time of≥2 h,2(3.6%)received timely LSIs.Pre-hospital care times of≥2 h were associated with delayed LSIs and with in-hospital death(unadjusted OR 4.3;95%CI 1.4–13.0).Conclusions:Timely completion of LSI when indicated was completed in a small proportion of patients and reflects previous research demonstrating delayed processes and errors even in advanced trauma systems.Timely delivery of a high proportion of LSIs was associated with improved outcomes among patients presenting with haemorrhagic shock after injury.Provision of LSIs in the pre-hospital phase of trauma care has the potential to improve outcomes.
文摘AIM:To compare the tear film quantity and stability parameters in keratoconus(KCN)and normal eyes using test breakup time(TBUT),noninvasive TBUT(NITBUT),and Schirmer test.METHODS:All participants(n=166),including patients with KCN and age-matched healthy individuals with normal corneas,were recruited from those referred to Farabi Eye Hospital,Iran,in 2023.To better account for genetic and environmental factors,the control group comprised healthy individuals who were relatives of KCN patients and had normal corneal topography.Tear quantity parameters were evaluated in the following order:NITBUT,TBUT,and Schirmer tests.RESULTS:The mean age of cases in KCN(61.7%males)and normal(63.5%males)participants was 27.54±5.44y(range 19 to 38)and 27.52±5.63y(range 20 to 38),respectively(P=0.976).NIBUT,TBUT,and Schirmer’s tests were significantly lower in KCN group compared to normal controls(all P<0.001).The mean difference for NIBUT was-7.81s(P<0.001),and for TBUT was-7.61s(P<0.001).Schirmer test values were also significantly lower in the KCN group,with a mean difference of-5.61 mm compared to normal people(P<0.001).CONCLUSION:Our findings demonstrate significant tear film impairment in KCN.The reductions in NIBUT,TBUT and Schirmer scores highlight an underlying tear film dysfunction in KCN that extends beyond the morphological changes of the cornea.
基金supported by the National Natural Science Foundation of China(grant no.32371866)。
文摘Drought influences carbon fixation by plants.Therefore,elucidating its impact on carbon fluxes in plants at the ecosystem level is crucial for assessing their role in mitigating climate change.Using carbon fluxes and environmental factor data from FLUXNET sites,we analyzed the influence of drought on carbon fluxes,their drivers,time-lag effects,and recovery times across various climatic regions and seasons.Results showed drought significantly decreased gross primary production(GPP),ecosystem respiration,and net ecosystem productivity in arid regions but slightly increased carbon sequestration in humid regions.Summer droughts negatively affected vegetation carbon fluxes,partly offset by the positive impact of spring droughts.Nonforest carbon fluxes were more susceptible to drought effects than forest fluxes.Soil water content(SWC)was the main influence on changes in arid regions,whereas vapor pressure deficit(VPD)dominated humid regions.Decreased SWC and increased VPD reduced carbon sequestration in arid regions but increased it in humid regions.Increased VPD reduced GPP,leading to forest carbon loss,whereas decreased SWC reduced GPP,leading to nonforest carbon loss.The lag time of the drought effects on carbon fluxes was longer in humid regions(19.44 d)than in arid regions(14.71 d).Compared to nonforest areas(16.74 d and 57 d for drought lag and recovery time,respectively),forest areas had a longer lag(18.81 d)and recovery time(92 d).The findings revealed discrepancies in the main factors regulating vegetation carbon fluxes during droughts between arid and humid regions and between forest and nonforest ecosystems.These insights provide a new perspective on understanding and simulating carbon-climate feedback.Enhancing ecosystem diversity is a feasible measure to increase drought resistance.
文摘Overseas investors are enthusiastic about the Chinese stock market as the equities are attractively priced and investors can expect profitable returns in the long「un. This is the verdict of Mark Makepeace, head of FTSE Russell, the second largest index provider in the world, whose organization will include Chinese shares in its major benchmarks.
基金funded by the National Key R&D Project‘Innovation and Integration of Key Technologies for Integration of Agricultural Machinery and Agronomy in Weak Links of Hybrid Mid-season Rice in Hilly Areas of Southwest China’(2023YFD2301901).
文摘Chilo suppressalis(Walker)is one of the most important rice pests worldwide,posing a significant challenge to effective control.To develop a precision-timed,eco-friendly management strategy,overwintering population investigation and dynamic monitoring of C.suppressalis populations were conducted in the Meishan region of Sichuan,China,from 2023 to 2024.The optimal timing for insecticide application was estimated,followed by field trials evaluating the efficacy of different insecticides.Results demonstrated that the peak emergence of first-generation adults typically occurred in early July(under the environmental conditions of the Meishan region),with the ambient humidity below 75%and temperature around 29◦C.Pesticide efficacy trials show that insecticide combinations exhibited superior control.Notably,a combined treatment of emamectin benzoate⋅methoxyfenozide+chlorantraniliprole achieved the highest control efficacy(90.05%)and a corresponding yield of 12,491.55 kg/ha.All tested treatments were determined to be safe for rice growth.Furthermore,this optimized strategy resulted in notable economic benefits,including a 50%reduction in pesticide usage and cost savings of 4796.15 CNY compared to conventional practices.This study provides valuable insights into sustainable rice production and pest management and,for the first time,proposes a precision application time window based on intelligent monitoring.
基金supported by the Research Fund of the National Natural Science Foundation of China(No.52374205)the Fundamental Research Project of the Educational Department of Liaoning Province(No.JYTMS20230793)the Research Fund of the State Key Laboratory of Coal Resources and Safe Mining,CUMT(No.YJY-XD-2024-A-016).
文摘To address the key scientific challenge of monitoring the dynamic fracturing of surrounding rock in deep roadways,this study systematically investigates the quantitative relationship between stress and charge signals during coal mass loading.By integrating innovative analytical approaches,introducing quantitative evaluation indices,and developing a charge–stress inversion model,and incorporating underground monitoring practices,significant progress has been achieved in elucidating the correlation between stress variations and charge signals throughout the entire coal mass fracturing process.First,in the field of stress–charge correlation analysis,empirical mode decomposition(EMD)was combined with wavelet coherence analysis for the first time,enabling the removal of slow-varying stress trends while retaining high-frequency fluctuations.This approach allowed for the quantitative characterization of the evolution of coherence between stress variations and charge fluctuations across multiple time scales.Second,coherence skewness and the proportion of high-coherence intervals were innovatively introduced to examine the influence of time scale selection on correlation results.On this basis,a criterion for determining the near-optimal observation scale of charge signals was proposed,providing a quantitative reference for time scale selection in similar signal analyses.Finally,by correlating charge signals with coal damage factors and stress states,a charge-based damage evolution equation was established to achieve effective stress inversion.Combined with in situ monitoring of stress and charge in roadway surrounding rock,this approach revealed the correlation characteristics of stress and charge intensity responses during the dynamic fracturing process.The results indicate,first,that charge signals are not significantly correlated with the absolute stress level of coal but are directly associated with stress variations following coal damage and failure,with the amplitude of charge fluctuations increasing alongside stress fluctuations.Second,coherence between stress and charge signals varies markedly across time scales,with excessively small or large scales leading to distortion,and the scale corresponding to the peak proportion of intervals with coherence>0.8 was identified as the near-optimal observation scale.Third,charge signals can effectively characterize coal damage factors,and the established damage evolution equation can effectively invert stress variation trends.Fourth,in underground roadways,zones of dynamic fracturing in surrounding rock are commonly located in areas where stress concentration overlaps with regions of high charge intensity,further confirming the strong consistency between charge and stress variations.These findings improve the theoretical framework of charge signal responses in loaded coal and provide a scientific basis for precise“stress-charge”monitoring of dynamic disasters,offering practical potential for engineering applications.
基金supported by the National Key Research and Development Program of China(2022YFD1200400)the National Natural Science Foundation of China(32272111)+4 种基金Special fund for youth team of the Southwest Universities(SWU-XJPY202306)Chongqing Natural Science Foundation(CSTB2024NSCQLZX0012)Modern Agro-industry Technology Research System(CARS-12)Chongqing Modern Agricultural Industry Technology System(COMAITS202504)Biological Breeding-National Science and Technology Major Project(2022ZD04008).We sincerely appreciate the Plant Editors team for English language editing of the manuscript,which significantly improved its clarity and overall quality.
文摘Flowering time is a critical agronomic trait with a profound effect on the productivity and adaptabillity of rapeseed(Brassica napus L.).Strategically advancing flowering time can reduce the risk of yield losses due to extreme climatic conditions and facilitate the cultivation of subsequent crops on the same land,thereby enhancing overall agricultural efficiency.In this review,we synthesize current information on flowering time regulation in rapeseed through an integrated analysis of its genetic,hormonal,and environmental dimensions,emphasizing their crosstalk and implications for yield.We consolidate multi-omics evidence from population genetics,functional genomics,and systems biology to create a haplotype-based framework that overcomes the trade-off between flowering time and yield,providing support for the precision breeding of early-maturing cultivars.The insights presented here could inform future research on flowering time regulation and guide strategies for increasing rapeseed productivity.
基金National Natural Science Foundation of China under Grant Nos.51979205 and 51939008。
文摘This research is focused on the calculation of a reasonable detonator delay time for realizing cut blast vibration control.First,the viscoelastic rock mass parameters corresponding to the engineering rock mass quality classification were determined based on wave theory of Kelvin medium.Then,a calculation model was obtained for the millisecond-delay cut blast vibration in Kelvin media using the Starfield charge superposition principle.Further,the influence of the delay time on the cut blast vibration was quantitatively analyzed and a method for calculating the reasonable cut blasting millisecond delay time is proposed according to the principle of dimensional analysis.Finally,field tests were used to verify the applicability of the method.The results show that 5 ms to 20 ms is a better detonator delay time range and cut blasting vibration can be effectively controlled using the delay time calculated by the calculation model described in this paper.
基金supported by SHINE and Shanghai Municipal Science and Technology Major Project(No.2017SHZDZX02).
文摘The Shanghai High Repetition Rate XFEL and Extreme Light Facility(SHINE)is currently under construction as one of the world’s most advanced hard X-ray free-electron laser facilities.The timing system,as an essential part of the free-electron laser facility,provides precise timing of trigger pulse signals for a range of devices to ensure that particles are generated and accelerated to the designed energy while enabling the precise measurement of beam parameters.To precisely distribute and synchronize the 1.003086 MHz(1300/1296)timing signals over a distance of approximately 3.1 km based on White Rabbit technology,three technical routes have been proposed.This paper begins with a description of the design and development process of the timing system for the SHINE project,which culminates with the determination of the design scheme.During the installation and commissioning of the timing system,the jitter accuracy of the timing signal was tested and found to be less than 10 ps,which meets the requirements of the project.Furthermore,the precise clock synchronization signal provided by the timing system supported the joint debugging of various related systems and realization of beam acquisition.
基金supported initially by the LIFE FoResMit Project(LIFE14 CCM/IT/000905)。
文摘Peri-urban plantations in the Mediterranean are often degraded due to human inactivity and climate change,leading to a loss of ecosystem services and biodiversity.This study investigates the impact of different thinning practices on carbon sequestration and tree stability in a degraded periurban plantation in the Italian Apennines,six years after thinning.Three treatments were compared:(a)moderate thinning from below(-25%biomass),representing the typical practice;(b)intense selective thinning(-35%biomass),representing an innovative approach;and(c)no management as the control.Growth projections were used to estimate carbon recovery for these treatments,based on site-specific models calibrated with real data.The results show that both thinning approaches increased carbon sequestration over time,with the innovative thinning achieving a 7%higher annual carbon sequestration rate than traditional thinning and 8%more than the control.Estimated payback times were9 years for recovering the harvested volume in both thinning approaches,10 years for innovative thinning to surpass traditional thinning,17 years for innovative thinning to surpass the control,and 24 years for traditional thinning to surpass the control.Additionally,tree mechanical stability improved significantly in both thinning treatments after two years,with further increases observed in the innovative thinning group after six years.These results suggest that selective thinning can accelerate forest recovery and carbon sequestration,especially in areas with high stem density,where it can reduce the negative impacts of tree mortality and deadwood accumulation.However,careful planning is required to mitigate potential short-term stability is sues,particularly in challenging environments(e.g.,windy conditions,steep slopes).Forest management strategies should therefore aim to balance growth,carbon storage,and tree stability,considering both long-term sustainability and local environmental conditions.The findings are particularly relevant for current climate change mitigation strategies,emphasizing that thinning should be carefully tailored to forest type and conditions to maximize benefits in carbon credit generation and sustainable forest management practices.