Torreya grandis'Merrillii'is a well-known nut in South China with high nutritional value.Severe premature seed abscission limits the industrial development of T.grandis by causing serious economic losses.Howev...Torreya grandis'Merrillii'is a well-known nut in South China with high nutritional value.Severe premature seed abscission limits the industrial development of T.grandis by causing serious economic losses.However,the physiological mechanisms of seed abscission in T.grandis remain poorly understood.To gain insight into the relationships between carbohydrate status and seed abscission,three-year-old seed-bearing branches were taken as representative materials for the entire tree.Furthermore,the time course of changes in the photosynthetic rate and the non-structural carbohydrate(NSC)dynamics were monitored in the main sources(the one-year-old and two-year-old shoots),and the dry weight and NSC levels of sinks(the seeds,current female cone cluster,and current vegetative cluster)across all seed development stages were recorded.The cumulative seed abscission rate significantly increased,reaching 91.5%from 0 to 72 days after seed protrusion time(SPT).NSC levels in the main sources significantly decreased by 56%-79%,accompanied by a significantly increased photosynthesis rate of 17.1%-49.1%during that period and increased NSC levels in the three sinks.The gene expression level of cell wall invertase(TgCWIN)was significantly correlated with sucrose,fructose,and glucose levels.The carbon storage capacity of the main sources significantly decreased from 6.03 to3.14 mmol C·d^(-1),with a stable photosynthetic capacity,from 0 to 72 days after SPT,whereas the carbon demand of the three sinks showed a continuously increasing trend from 3.14 to 7.71 mmol C·d^(-1).In addition,sucrose supplementation significantly decreased the cumulative seed abscission rate.These results suggest that storage carbohydrates play a major role in the regulatory mechanism of seed abscission in T.grandis.Our study provides a theoretical basis for improving T.grandis yield through establishing a better carbon balance between sources and sinks using timely fertilization or proper pruning procedures.展开更多
BACKGROUND In randomized controlled trials(RCTs),the placebo arm has often been ignored as the attention tends to be focused on the treatment arm.We undertook a meta-analysis based on the data from the placebo arm in ...BACKGROUND In randomized controlled trials(RCTs),the placebo arm has often been ignored as the attention tends to be focused on the treatment arm.We undertook a meta-analysis based on the data from the placebo arm in RCTs of hepatocellular carci-noma(HCC),the response rates and survival status,and adverse events(AEs)were summarized and evaluated.AIM To systematically evaluate the response rates,survival status and AEs in the placebo arms of RCTs for HCC.METHODS A systematic search was performed on PubMed,Ovid MEDLINE,Embase and Cochrane Library to identify relevant trials evaluating the efficacy of drugs for the treatment of HCC,published until December 31,2023.Statistical analysis was performed using R statistical software(version 4.3.2).RESULTS A total of 18 RCTs,involving 2390 patients,met the criteria for inclusion in the meta-analysis.The pooled overall disease control rate and objective response rate in the placebo group were 38%[95%confidence interval(CI):33%-42%]and 1%(95%CI:1%-2%),respectively.Overall survival and progression-free survival in the placebo group were 7.9 months(95%CI:7.6-8.31 months)and 1.9 months(95%CI:1.6-2.1 months),respectively.The incidence of grade 3 or 4 AEs was 37%(95%CI:30%-43%).Additionally,the incidence of interruptions or dose reductions due to AEs was 20%(95%CI:13%-27%),while the incidence of treatment discontinuation due to AEs was 9%(95%CI:6%-12%).CONCLUSION Over one-third of advanced HCC patients exhibit therapy-free disease control,with placebo-arm AEs observed.These findings guide single-arm trials design and enhance patient acceptance of anticancer therapies.展开更多
This study aimed to optimize the application rates and base-topdressing ratios of nitrogen and potassium for flue-cured tobacco in Chaling,Zhuzhou,Hunan.The tobacco variety‘Yunyan 87’was planted and subjected to eig...This study aimed to optimize the application rates and base-topdressing ratios of nitrogen and potassium for flue-cured tobacco in Chaling,Zhuzhou,Hunan.The tobacco variety‘Yunyan 87’was planted and subjected to eight different treatments with different application rates and base-topdressing ratios of nitrogen and potassium.The effect of different treatments on the agronomic traits,dry matter accumulation,yield,and quality of tobacco were compared.The results showed that the growth period of each treatment became shortened as the application rates of nitrogen and potassium decreased and as the base-topdressing ratios of nitrogen and potassium increased.The dry matter accumulation decreased with the reduction in the application rates of nitrogen and potassium.The yield and output value of T1 were the highest,reaching 2097.39 kg/hm^(2)and 65018.90 yuan/hm^(2),respectively,both significantly increasing by 57.5%compared with those of the control(CK).In addition,the proportions of leaves of high and mid-high grade in T1 were also the highest,reaching 73.31%and 88.79%,respectively,both higher than those of CK.The appearance evaluation results showed that the appearance quality scores of tobacco leaves of grades B2F and C3F in T1 were the highest,reaching 51 points,both of which were 3 points higher than that those of CK.All the treatments were consistent in terms of color,maturity,leaf structure,body,oil,and color intensity.Therefore,it was suggested that the tobacco production in Chaling should appropriately increase the proportions of nitrogen and potassium as base fertilizers on the basis of conventional fertilization,which was conducive to improving the yield and appearance quality of flue-cured tobacco.展开更多
BACKGROUND In the treatment of rectal cancer,a temporary loop ileostomy(TLI)is created after low anterior resection to protect bowel function in the postoperative period.Dehydration and kidney failure are significant ...BACKGROUND In the treatment of rectal cancer,a temporary loop ileostomy(TLI)is created after low anterior resection to protect bowel function in the postoperative period.Dehydration and kidney failure are significant potential complications in loop ileostomies.Compared to late closure(3-6 months),early closure(10-14 days)of the TLI may facilitate faster patient recovery and shorter hospital stays.AIM To compare early and late closure of TLIs and demonstrate that early stoma closure can be performed without increasing morbidity.METHODS This study included patients who underwent TLI for rectal cancer,with data collected prospectively between June 2016 and October 2024 and analyzed retrospectively.Patients whose stomas were closed in the late period(3-6 months)between June 2016 and October 2022(group A)were compared with those who underwent early closure(10-14 days)between October 2022 and 2024(group B),with the primary outcome being complication rate and the secondary outcome being quality of life.RESULTS A total of 270 TLIs were created(70.9%).Of these,120(44.4%)were closed in the late period(group A),and 150(55.6%)were closed in the early period(group B).There was no statistically significant difference between group A and group B in terms of demographic and clinicopathological characteristics(P>0.05).Perioperative(anesthesia management,operative time,blood loss,surgical technique)and postoperative findings(anastomotic leak,infection)were similar between the two groups and were not statistically significant(P>0.05).There were no statistically significant differences in complication rates as the primary outcome between the two groups.Quality of life as a secondary outcome was significantly higher in the early closure group(P<0.05).CONCLUSION No statistically significant difference was found between early and late loop ileostomy closure in terms of perioperative and postoperative morbidity.Early closure accelerated patients’psychological and social recovery.展开更多
The karst forest in southwestern China is characterized by thin soil layers,numerous fissures and holes,resulting in low soil water availability and poor water retention,making it challenging for plant growth and surv...The karst forest in southwestern China is characterized by thin soil layers,numerous fissures and holes,resulting in low soil water availability and poor water retention,making it challenging for plant growth and survival.While the relationship between plant functional traits and tree growth performance has been extensively studied,the links between tree seasonal growth and drought-tolerant traits in tree species with different leaf habit remains poorly understood.This study evaluated the associations between four-year averaged rainy season stem diameter growth rate and 17 branch and leaf traits across evergreen and deciduous species in a tropical karst forest in southwest China.The cross-species variations in tree growth rates were related to plant hydraulic traits(e.g.,vessel lumen diameter,xylem vessel density,stomatal density,and stomatal size)and leaf anatomical traits(e.g.,total leaf thickness,lower/upper epidermis thickness,and spongy thickness).The growth of evergreen trees exhibited lower hydraulic efficiency but greater drought tolerance than deciduous tree,which enabled them to maintain higher persistence under low soil water availability and consequently a relatively longer growing season.In contrast,deciduous species showed no correlation between their functional traits and growth rate.The distinct water use strategies of evergreen and deciduous trees may offer a potential explanation for their co-existence in the tropical karst forests.展开更多
To the Editor:The recent study by Rochdi et al[1]comparing the effects of two coenzyme Q10(CoQ10)doses(100 mg/day vs.200 mg/day)on male fertility parameters represents a significant advancement in evidence-based treat...To the Editor:The recent study by Rochdi et al[1]comparing the effects of two coenzyme Q10(CoQ10)doses(100 mg/day vs.200 mg/day)on male fertility parameters represents a significant advancement in evidence-based treatment of idiopathic oligoasthenozoospermia.The findings demonstrate a clear dose-response relationship with profound clinical implications that deserve focused attention.The most compelling finding is the 53%relative increase in pregnancy rates between the higher and lower dose groups(23%vs.15%,P<0.001).This 8-percentage point absolute difference translates to a number needed to treat(NNT)of 12.5,meaning that for every 12-13 men treated with the higher dose instead of the lower dose,one additional pregnancy would be achieved.Given that male factor infertility contributes to approximately 50%of all infertility cases globally,this dose-response relationship has immediate clinical relevance.展开更多
Gypsum rocks are highly susceptible to mechanical deterioration under the coupled effects of wet-dry(W-D)cycles and flow rates,which significantly influence the stability of underground excavations.Despite extensive r...Gypsum rocks are highly susceptible to mechanical deterioration under the coupled effects of wet-dry(W-D)cycles and flow rates,which significantly influence the stability of underground excavations.Despite extensive research on the effects of W-D cycles,the coupling influence of flow rates and W-D cycles on gypsum rocks remains poorly understood.This study investigates the mechanical behavior and deterioration mechanisms of gypsum rocks subjected to varying W-D cycles and flow rate conditions.Axial compression tests,along with nuclear magnetic resonance(NMR)techniques,were employed to analyze the stress-strain response and microstructural changes.Based on the disturbed state concept(DSC)theory,a W-D deterioration model and a DSC-based constitutive model were developed to describe the degradation trends and mechanical responses of gypsum rocks under different conditions.The results demonstrate that key mechanical indices,elastic modulus,cohesion,uniaxial compressive strength(UCS),and internal friction angle,exhibit logarithmic declines with increasing W-D cycles,with higher flow rates accelerating the deterioration process.The theoretical models accurately capture the nonlinear compaction behavior,peak stress,and post-peak response of gypsum specimens.This study provides valuable insights for predicting the mechanical behavior of gypsum rocks and improving the stability assessments of underground structures under complex environmental conditions.展开更多
This paper studies the global existence and large-time behaviors of weak solutions to the kinetic particle model coupled with the incompressible Navier-Stokes equations in IR3.First,we obtain the global weak solution ...This paper studies the global existence and large-time behaviors of weak solutions to the kinetic particle model coupled with the incompressible Navier-Stokes equations in IR3.First,we obtain the global weak solution using the characteristic and energy methods.Then,under the small assumption of the mass of the particle,we show that the solutions decay at the algebraic time-decay rate.Finally,it is also proved that the above rate is optimal.It should be remarked that if the particle in the coupled system vanishes(i.e.f=O),our works coincide with the classical results by Schonbek[32](J Amer Math Soc,1991,4:423-449),which can be regarded as a generalization from a single fuid model to the two-phase fluid one.展开更多
This study utilizes two complementary models,the Time-Varying Parameter Vector Autoregressive Diebold–Yilmaz(TVP-VAR-DY)and the Time-Varying Parameter Vector Autoregressive Barunik–Křehlik(TVP-VAR-BK),to investigate...This study utilizes two complementary models,the Time-Varying Parameter Vector Autoregressive Diebold–Yilmaz(TVP-VAR-DY)and the Time-Varying Parameter Vector Autoregressive Barunik–Křehlik(TVP-VAR-BK),to investigate the dynamic volatility transmission between exchange rates and stock returns in major commodity-exporting and-importing countries.The analysis focuses on periods of quantitative easing(QE)and quantitative tightening(QT)from March 15,2020 to December 30,2022.The countries examined are Canada and Australia(major commodity exporters)and the UK and Germany(major commodity importers).An essential contribution of this paper is new empirical insights into the dynamics of stock market returns and the transmission of volatility between these markets and exchange rates during the QE and QT periods.The results reveal that causality primarily flows from stock markets to exchange rates,especially during the QT period across all investment horizons.The Toronto Stock Exchange(TSX)emerges as the principal net driver among the markets under study.Furthermore,the Canadian exchange rate(USDCAD)and the Australian Stock Exchange(ASX)are the most significantly affected indices within the network across various investment horizons(excluding the long-term).These findings underscore the importance for investors and policymakers to consider the interplay between exchange rates and stock market returns,particularly in the context of the QE and QT periods,as well as other economic,political,and health-related events.Our findings are relevant to various stakeholders,including governments,traders,portfolio managers,and multinationals.展开更多
Acute cholangitis(AC)is a heterogeneous disease with considerable variation in clinical presentation and high medical costs.Although the overall mortality rate is decreasing.However,the mortality in severe AC ranged f...Acute cholangitis(AC)is a heterogeneous disease with considerable variation in clinical presentation and high medical costs.Although the overall mortality rate is decreasing.However,the mortality in severe AC ranged from 10%-30%due to sepsis,multi-organ failure,and systemic inflammatory response syndrome.Assessing the predictors of poor outcomes,including mortality,intensive care unit(ICU)admission,and hospital stay,is vital for early and effective intervention.We assessed the predictors of mortality and ICU admission in patients with AC.We conducted a literature search in PubMed/MEDLINE,Google Scholar,and Cochrane Library for relevant articles.The keywords used were acute cholangitis,biliary cholangitis,predictors,mortality,ICU admission,and Hospital stay.In addition,we assessed the role of early vs late endoscopic retrograde cholangiopancreatography on the outcomes.Old age,end-organ failure,red cell distribution width to albumin ratio,neutrophil-to-lymphocyte ratio,platelet-lymphocyte ratio,the need for ventilator support,diabetes,electrolyte imbalance,procalcitonin-to-albumin ratio,C-reactive protein-to-albumin,Glasgow Coma Scale,and systolic hypertension are predictors of poor outcomes in AC of varying etiology,and concurrent acute pancreatitis was not associated with ICU admission.展开更多
In this study,a uniaxial cyclic compression test is conducted on coal-rock composite structures under two cyclic loads using MTSE45.104 testing apparatus to investigate the macro-mesoscopic deformation,damage behavior...In this study,a uniaxial cyclic compression test is conducted on coal-rock composite structures under two cyclic loads using MTSE45.104 testing apparatus to investigate the macro-mesoscopic deformation,damage behavior,and energy evolution characteristics of these structures under different cyclic stress disturbances.Three loading and unloading rates(LURs)are tested to examine the damage behaviors and energy-driven characteristics of the composites.The findings reveal that the energy-driven behavior,mechanical properties,and macro-micro degradation characteristics of the composites are significantly influenced by the loading rate.Under the gradual cyclic loading and unloading(CLU)path with a constant lower limit(path I)and the CLU path with variable upper and lower boundaries(path II),an increase in LURs from 0.05 to 0.15 mm/min reduces the average loading time by 32.39%and 48.60%,respectively.Consequently,the total number of cracks in the samples increases by 1.66-fold for path I and 1.41-fold for path II.As LURs further increase,the energy storage limit of samples expands,leading to a higher proportion of transmatrix and shear cracks.Under both cyclic loading conditions,a broader cyclic stress range promotes energy dissipation and the formation of internal fractures.Notably,at higher loading rates,cracks tend to propagate along primary weak surfaces,leading to an increased incidence of intermatrix fractures.This behavior indicates a microscopic feature of the failure mechanisms in composite structures.These results provide a theoretical basis for elucidating the damage and failure characteristics of coal-rock composite structures under cyclic stress disturbances.展开更多
Efficient nitrogen management is crucial for developing sustainable strategies aimed at enhancing yield while mitigating negative environmental impacts.However,research focusing on this aspect in the production of fre...Efficient nitrogen management is crucial for developing sustainable strategies aimed at enhancing yield while mitigating negative environmental impacts.However,research focusing on this aspect in the production of fresh maize is limited.Therefore,this study analyzed the effects of nitrogen application rates on the yields of 40 sweet and 44 waxy maize varieties at five sites in Zhejiang Province,China,from 2015 to 2019.The nitrogen application rates were categorized as either relatively high(RHN,>300 kg ha^(-1) for sweet maize and>320 kg ha^(-1) for waxy maize)or relatively low(RLN).An increase in nitrogen application rates significantly reduced nitrogen fertilizer partial productivity in both sweet and waxy maize(R^(2)=0.616,P<0.01;R^(2)=0.643,P<0.01),indicating that the optimum nitrogen application rates in this study might be the lowest values(160 kg ha^(-1) for sweet maize and 180 kg ha^(-1) for waxy maize).The kernel number per ear of sweet maize had a potentially more significant impact on fresh grain yield than the 1,000-fresh kernel weight under both RLN and RHN.In waxy maize,1,000-kernel weight contributed more to fresh grain yield under RLN,while kernel number per ear and 1,000-kernel weight cooperatively affected the yield under RHN.This study found that sweet maize required taller plant and ear heights,along with an optimal ear-plant height ratio,to enhance dry matter accumulation and increase source size,particularly under RLN,and to ultimately achieve a higher fresh grain yield.In contrast,a lower ear height and ear-plant height ratio in waxy maize probably contributed more to the greater kernel number and weight under RLN,likely due to a lower ear height which can reduce the distance between sink and source,enabling more efficient photoassimilate allocation to the ear.展开更多
Quanto options allow the buyer to exchange the foreign currency payoff into the domestic currency at a fixed exchange rate. We investigate quanto options with multiple underlying assets valued in different foreign cur...Quanto options allow the buyer to exchange the foreign currency payoff into the domestic currency at a fixed exchange rate. We investigate quanto options with multiple underlying assets valued in different foreign currencies each with a different strike price in the payoff function. We carry out a comparative performance analysis of different stochastic volatility (SV), stochastic correlation (SC), and stochastic exchange rate (SER) models to determine the best combination of these models for Monte Carlo (MC) simulation pricing. In addition, we test the performance of all model variants with constant correlation as a benchmark. We find that a combination of GARCH-Jump SV, Weibull SC, and Ornstein Uhlenbeck (OU) SER performs best. In addition, we analyze different discretization schemes and their results. In our simulations, the Milstein scheme yields the best balance between execution times and lower standard deviations of price estimates. Furthermore, we find that incorporating mean reversion into stochastic correlation and stochastic FX rate modeling is beneficial for MC simulation pricing. We improve the accuracy of our simulations by implementing antithetic variates variance reduction. Finally, we derive the correlation risk parameters Cora and Gora in our framework so that correlation hedging of quanto options can be performed.展开更多
The shape of underground chambers in deep mining varies due to their geological environment and intended use,which results in different failure modes under the influence of mining activities.However,the effect of cham...The shape of underground chambers in deep mining varies due to their geological environment and intended use,which results in different failure modes under the influence of mining activities.However,the effect of chamber shape on the mechanism of structural integrity under dynamic load is still unclear.In this paper,granite samples with circular(C),rectangular(R),long ellipse(EL),and short ellipse(ES)holes were prepared.The dynamic mechanical response and cracking mechanism of granite were systematically analyzed using the split Hopkinson pressure bar(SHPB)test system and the hybrid finite and discrete element method(HFDEM).The results indicate that the dynamic strengths of granite with EL and ES represent the maximum and minimum values within the range of close strain rates,respectively.When EL granite is subjected to dynamic load,the axial stress concentration(in the load direction)is weak,and the transverse stress shows relative dispersion,which is the primary reason for its highest dynamic strength.The failure of granite with various holes primarily involves a tensile-shear mixed fracture,with relatively few pure typeⅡcracks.The chamber’s transverse span is the primary factor influencing the distribution range of the fracture area.展开更多
This study investigates extreme rainfall episodes along the eastern foothills of the Taihang Mountains in North China from 30 July to 1 August 2023.It focuses on two types of extreme hourly rainfall rates(HRRs),i.e.,t...This study investigates extreme rainfall episodes along the eastern foothills of the Taihang Mountains in North China from 30 July to 1 August 2023.It focuses on two types of extreme hourly rainfall rates(HRRs),i.e.,the maximum regionalaverage HRR and site-observed HRR,which exhibited sequential development over southern,middle,and northern key regions.These rainfall extremes occurred in an environment where a high-pressure barrier over North China prevented the intrusion of cold air masses from the north while a northward-moving typhoon remnant vortex and its associated low-level jet(LLJ)transported warm and moist airflow from the south.Two distinct echo evolution modes and convection initiation mechanisms are identified for the two types of extreme HRRs.The maximum regional-average HRR occurred when the LLJ arrived to the east of the key regions,while the maximum site-observed HRR occurred when the warmer vortex center influenced the regions.Taking the northern key region as a representation,at the time of the maximum regional-average HRR,slantwise ascent of the airflow along a warm-frontal-like boundary released energy related to symmetrical instability,resulting in stratiform rainfall with weak convective cores.The transport of locally initiated convection over the eastern plain region,where the atmospheric stratification was more potentially unstable,also significantly contributed.When the maximum site-observed HRR occurred,the terrain lifting of warm and moist southeast airflow led to intense convection over the mountain foothills.Overall,the passage of the warm-core typhoon remnant vortex and interaction with Taihang Mountains determined the timing and location of extreme HRRs across the key regions.展开更多
Objective The aim was to elucidate the effects of N rates on rice canopy microclimate and community health so as to provide a sci- entific basis for studying the production potential in irrigated rice with healthy can...Objective The aim was to elucidate the effects of N rates on rice canopy microclimate and community health so as to provide a sci- entific basis for studying the production potential in irrigated rice with healthy canopy. Method The effects of rice population structure traits under different N rates on rice canopy temperature, relative humidity （ RH）, light transmittance and sheath blight were studied by using Sunscan canopy analysis system and HOBO（ Pro Temp/RH IS logger）. Result The results showed that leaf area index, plant height and tiller number had significant effects on canopy cooling, RH enhancing and light reducing. Extremely significant multiple linear regression relationships existed among canopy day temperature, day RH, LAI and tiller number, and among light transmittance, tiller number and plant height. At flowering stage, per unit LAI could result in a day-maximum-temperature （Tmax） deceasing of 0.87℃ and a day-minimum-RH （RHmin） enhancing of 2.5% within canopy. Similarly, 100 plants per ms could respectively cause a Tmax deceasing of 1.23℃ and an RHmin enhancing of 3.3% in rice canopy. And per 10 cm plant height and 100 plants per m^2 could respectively reduce 9.3% and 7.8% of light in canopy. Conclusion Sheath blight disease index was significantly enhanced as the canopy day temperature decreased, day RH increased and light transmittance reduced. Bigger canopy from higher nitrogen level treatment leads to a more stable canopy microclimate with little changes in temperature and RH during day and night, which has the risk of worsening canopy health. Thus, moderately controlling the space development of canopy is the basis of constructing healthy canopy in rice.展开更多
Recent advances in additive manufacturing have enabled the construction of metallic lattice structures with tailored mechanical and functional properties.One potential application of metallic lattice struc-tures is in...Recent advances in additive manufacturing have enabled the construction of metallic lattice structures with tailored mechanical and functional properties.One potential application of metallic lattice struc-tures is in the impact load mitigation where an external kinetic energy is absorbed by the deformation/crushing of lattice cells.This has motivated a growing number of experimental and numerical studies,recently,on the crushing behavior of additively produced lattice structures.The present study overviews the dynamic and quasi-static crushing behavior of additively produced Ti64,316L,and AlSiMg alloy lattice structures.The first part of the study summarizes the main features of two most commonly used additive processing techniques for lattice structures,namely selective-laser-melt(SLM)and electro-beam-melt(EBM),along with a description of commonly observed process induced defects.In the second part,the deformation and strain rate sensitivities of the selected alloy lattices are outlined together with the most widely used dynamic test methods,followed by a part on the observed micro-structures of the SLM and EBM-processed Ti64,316L and AlSiMg alloys.Finally,the experimental and numerical studies on the quasi-static and dynamic compression behavior of the additively processed Ti64,316L,and AlSiMg alloy lattices are reviewed.The results of the experimental and numerical studies of the dynamic properties of various types of lattices,including graded,non-uniform strut size,hollow,non-uniform cell size,and bio-inspired,were tabulated together with the used dynamic testing methods.The dynamic tests have been noted to be mostly conducted in compression Split Hopkinson Pressure Bar(SHPB)or Taylor-and direct-impact tests using the SHPB set-up,in all of which relatively small-size test specimens were tested.The test specimen size effect on the compression behavior of the lattices was further emphasized.It has also been shown that the lattices of Ti64 and AlSiMg alloys are relatively brittle as compared with the lattices of 316L alloy.Finally,the challenges associated with modelling lattice structures were explained and the micro tension tests and multi-scale modeling techniques combining microstructural characteristics with macroscopic lattice dynamics were recommended to improve the accuracy of the numerical simulations of the dynamic compression deformations of metallic lattice structures.展开更多
Accurately correlating the sweating rate and the concentration of biomarkers in sweat is essential in many sweat-based diagnostic applications.These two measurements are always done simultaneously in wearable sweat se...Accurately correlating the sweating rate and the concentration of biomarkers in sweat is essential in many sweat-based diagnostic applications.These two measurements are always done simultaneously in wearable sweat sensing platforms.However,concentration measurements of biomarkers are always delayed on the timeline compared with their production,whereas there is no such delay for sweating rate.Thus,a timeline mismatch exists between these two measurements.This means that the concentration vs rate correlation constructed on the basis of such measurements will deviate from the actual correlation.This study demonstrates the existence of this mismatch and explains its cause using sweat Na^(+)measurements.It also proposes an effective approach that applies a point-by-point compensation for the delay between Na+measurements and the real-time sweating rates,such that the data on the repositioned concentration vs time curve correspond to exactly the same point on the timeline as their production.A vison sensor is developed to measure the sweating rate with high accuracy at a frequency of more than 0.1 Hz.Off-body and on-body measurements of sweating rate and Na^(+)concentration are carried out,and concentration–rate correlations are constructed using both measured and repositioned concentration curves.The least squares and random forest methods are employed to fit the constructed correlations and evaluate the reliability of the proposed approach.The use of the repositioned concentration curve gives a constructed correlation that is much closer to the actual one.This study indicates the necessity to rearrange sensor-measured biomarker concentration vs time curves when correlations of concentration with sweating rate need to be constructed and proposes a practical point-by-point data repositioning strategy for doing so.The results presented here will benefit the study of sweat biomarkers with unclear correlations with sweating rate,as well as providing a basis for the development of more reliable sweat-based diagnostic methods.展开更多
South Florida’s natural forest ecosystems,including pine rocklands and hardwood hammocks,are threatened by land use change and urbanization,invasive species,and climate change.It is critical to understand the respons...South Florida’s natural forest ecosystems,including pine rocklands and hardwood hammocks,are threatened by land use change and urbanization,invasive species,and climate change.It is critical to understand the responses of these ecosystems to anthropogenic disturbances to conserve the remnants of the USA natural subtropical forests.Using dendrochronology,long-term growth patterns were characterized in three dominant native tree species:Bursera simaruba,Swietenia mahagoni,and Pinus elliottii.Core samples were collected from>30 individuals of each species in hardwood hammocks(B.simaruba and S.mahagoni)and pine rocklands(P.elliottii)to examine growth patterns.Relationships between annual tree growth rates and climatic variables were assessed to address three questions:(1)What are the climatic drivers of growth in these three South Florida tree species?(2)Are their growth rates stable or changing through time?and(3)Are tree growth rates affected by urbanization?Standardized growth rates of the three species have changed through time,with small young trees showing accelerated growth through time,whereas larger,older trees showed declining growth rates.S.mahagoni and B.simaruba grew faster in urbanized parks than in more natural parks,whereas P.elliottii grew slower in urban parks.There were positive correlations between tree growth and the current year’s fall precipitation and no discernable effects of the current year’s monthly temperatures on growth rates of any of the species.These results suggest that the foundational tree species of the southern USA endangered pine rocklands and hardwood hammocks may be vulnerable to ongoing changes in precipitation and temperature as well as other environmental effects associated with urbanization.展开更多
Understanding the molecular relevance of metabolic rate(MR)is crucial for unveiling the mechanisms driving the evolution of animals.In this study,we investigated the association between mitochondrial DNA characteristi...Understanding the molecular relevance of metabolic rate(MR)is crucial for unveiling the mechanisms driving the evolution of animals.In this study,we investigated the association between mitochondrial DNA characteristics and both resting and maximal MRs in conjunction with life-history traits among 139 species of teleost fish,We gathered fish MR data from various sources and procured sequences of 13 mitochondrial protein-encoding genes.We calculated the absolute substitution rate for entire nucleotide sequences and 4-fold degenerate sites of each gene,along with encoding amino acid sequences.Using the phylogenetic comparative method,we then explored the associations between MR and mitochondrial DNA absolute substitution rate.Additionally,we screened MR-associated single nucleotide variants in mitochondrial DNA.The findings indicate no positive correlation between MRs and any substitution rate values of both combined sequences and individual mitochondrial protein-coding genes,refuting the MR hypothesis.Instead,both maximum body size and longevity correlated negatively with molecular substitution rates,suggesting their influences on both mutation and fixation within mitochondrial genes in fish.Results also revealed significant correlations between base variation at ATP6_169 and both resting MR and maximum MR,identifying the unique ATP6_169G in Scombridae fish,which results in an extremely low isoelectric point(pl)value of the ATP6 protein.Considering its functional significance,the ATP6_169G in Scombridae fish might link to their lifestyle characterized by fast locomotion and high metabolic demands alongside a slower molecular evolutionary rate.展开更多
基金supported by grants from the National Science Foundation of China(Grant Nos.U20A2049 and 32271922)。
文摘Torreya grandis'Merrillii'is a well-known nut in South China with high nutritional value.Severe premature seed abscission limits the industrial development of T.grandis by causing serious economic losses.However,the physiological mechanisms of seed abscission in T.grandis remain poorly understood.To gain insight into the relationships between carbohydrate status and seed abscission,three-year-old seed-bearing branches were taken as representative materials for the entire tree.Furthermore,the time course of changes in the photosynthetic rate and the non-structural carbohydrate(NSC)dynamics were monitored in the main sources(the one-year-old and two-year-old shoots),and the dry weight and NSC levels of sinks(the seeds,current female cone cluster,and current vegetative cluster)across all seed development stages were recorded.The cumulative seed abscission rate significantly increased,reaching 91.5%from 0 to 72 days after seed protrusion time(SPT).NSC levels in the main sources significantly decreased by 56%-79%,accompanied by a significantly increased photosynthesis rate of 17.1%-49.1%during that period and increased NSC levels in the three sinks.The gene expression level of cell wall invertase(TgCWIN)was significantly correlated with sucrose,fructose,and glucose levels.The carbon storage capacity of the main sources significantly decreased from 6.03 to3.14 mmol C·d^(-1),with a stable photosynthetic capacity,from 0 to 72 days after SPT,whereas the carbon demand of the three sinks showed a continuously increasing trend from 3.14 to 7.71 mmol C·d^(-1).In addition,sucrose supplementation significantly decreased the cumulative seed abscission rate.These results suggest that storage carbohydrates play a major role in the regulatory mechanism of seed abscission in T.grandis.Our study provides a theoretical basis for improving T.grandis yield through establishing a better carbon balance between sources and sinks using timely fertilization or proper pruning procedures.
文摘BACKGROUND In randomized controlled trials(RCTs),the placebo arm has often been ignored as the attention tends to be focused on the treatment arm.We undertook a meta-analysis based on the data from the placebo arm in RCTs of hepatocellular carci-noma(HCC),the response rates and survival status,and adverse events(AEs)were summarized and evaluated.AIM To systematically evaluate the response rates,survival status and AEs in the placebo arms of RCTs for HCC.METHODS A systematic search was performed on PubMed,Ovid MEDLINE,Embase and Cochrane Library to identify relevant trials evaluating the efficacy of drugs for the treatment of HCC,published until December 31,2023.Statistical analysis was performed using R statistical software(version 4.3.2).RESULTS A total of 18 RCTs,involving 2390 patients,met the criteria for inclusion in the meta-analysis.The pooled overall disease control rate and objective response rate in the placebo group were 38%[95%confidence interval(CI):33%-42%]and 1%(95%CI:1%-2%),respectively.Overall survival and progression-free survival in the placebo group were 7.9 months(95%CI:7.6-8.31 months)and 1.9 months(95%CI:1.6-2.1 months),respectively.The incidence of grade 3 or 4 AEs was 37%(95%CI:30%-43%).Additionally,the incidence of interruptions or dose reductions due to AEs was 20%(95%CI:13%-27%),while the incidence of treatment discontinuation due to AEs was 9%(95%CI:6%-12%).CONCLUSION Over one-third of advanced HCC patients exhibit therapy-free disease control,with placebo-arm AEs observed.These findings guide single-arm trials design and enhance patient acceptance of anticancer therapies.
文摘This study aimed to optimize the application rates and base-topdressing ratios of nitrogen and potassium for flue-cured tobacco in Chaling,Zhuzhou,Hunan.The tobacco variety‘Yunyan 87’was planted and subjected to eight different treatments with different application rates and base-topdressing ratios of nitrogen and potassium.The effect of different treatments on the agronomic traits,dry matter accumulation,yield,and quality of tobacco were compared.The results showed that the growth period of each treatment became shortened as the application rates of nitrogen and potassium decreased and as the base-topdressing ratios of nitrogen and potassium increased.The dry matter accumulation decreased with the reduction in the application rates of nitrogen and potassium.The yield and output value of T1 were the highest,reaching 2097.39 kg/hm^(2)and 65018.90 yuan/hm^(2),respectively,both significantly increasing by 57.5%compared with those of the control(CK).In addition,the proportions of leaves of high and mid-high grade in T1 were also the highest,reaching 73.31%and 88.79%,respectively,both higher than those of CK.The appearance evaluation results showed that the appearance quality scores of tobacco leaves of grades B2F and C3F in T1 were the highest,reaching 51 points,both of which were 3 points higher than that those of CK.All the treatments were consistent in terms of color,maturity,leaf structure,body,oil,and color intensity.Therefore,it was suggested that the tobacco production in Chaling should appropriately increase the proportions of nitrogen and potassium as base fertilizers on the basis of conventional fertilization,which was conducive to improving the yield and appearance quality of flue-cured tobacco.
文摘BACKGROUND In the treatment of rectal cancer,a temporary loop ileostomy(TLI)is created after low anterior resection to protect bowel function in the postoperative period.Dehydration and kidney failure are significant potential complications in loop ileostomies.Compared to late closure(3-6 months),early closure(10-14 days)of the TLI may facilitate faster patient recovery and shorter hospital stays.AIM To compare early and late closure of TLIs and demonstrate that early stoma closure can be performed without increasing morbidity.METHODS This study included patients who underwent TLI for rectal cancer,with data collected prospectively between June 2016 and October 2024 and analyzed retrospectively.Patients whose stomas were closed in the late period(3-6 months)between June 2016 and October 2022(group A)were compared with those who underwent early closure(10-14 days)between October 2022 and 2024(group B),with the primary outcome being complication rate and the secondary outcome being quality of life.RESULTS A total of 270 TLIs were created(70.9%).Of these,120(44.4%)were closed in the late period(group A),and 150(55.6%)were closed in the early period(group B).There was no statistically significant difference between group A and group B in terms of demographic and clinicopathological characteristics(P>0.05).Perioperative(anesthesia management,operative time,blood loss,surgical technique)and postoperative findings(anastomotic leak,infection)were similar between the two groups and were not statistically significant(P>0.05).There were no statistically significant differences in complication rates as the primary outcome between the two groups.Quality of life as a secondary outcome was significantly higher in the early closure group(P<0.05).CONCLUSION No statistically significant difference was found between early and late loop ileostomy closure in terms of perioperative and postoperative morbidity.Early closure accelerated patients’psychological and social recovery.
基金financially funded by the National Natural Science Foundation of China(3186113307,31770533,31870591)the West Light Talent Program of the Chinese Academy of Sciences(xbzg-zdsys-202218).
文摘The karst forest in southwestern China is characterized by thin soil layers,numerous fissures and holes,resulting in low soil water availability and poor water retention,making it challenging for plant growth and survival.While the relationship between plant functional traits and tree growth performance has been extensively studied,the links between tree seasonal growth and drought-tolerant traits in tree species with different leaf habit remains poorly understood.This study evaluated the associations between four-year averaged rainy season stem diameter growth rate and 17 branch and leaf traits across evergreen and deciduous species in a tropical karst forest in southwest China.The cross-species variations in tree growth rates were related to plant hydraulic traits(e.g.,vessel lumen diameter,xylem vessel density,stomatal density,and stomatal size)and leaf anatomical traits(e.g.,total leaf thickness,lower/upper epidermis thickness,and spongy thickness).The growth of evergreen trees exhibited lower hydraulic efficiency but greater drought tolerance than deciduous tree,which enabled them to maintain higher persistence under low soil water availability and consequently a relatively longer growing season.In contrast,deciduous species showed no correlation between their functional traits and growth rate.The distinct water use strategies of evergreen and deciduous trees may offer a potential explanation for their co-existence in the tropical karst forests.
文摘To the Editor:The recent study by Rochdi et al[1]comparing the effects of two coenzyme Q10(CoQ10)doses(100 mg/day vs.200 mg/day)on male fertility parameters represents a significant advancement in evidence-based treatment of idiopathic oligoasthenozoospermia.The findings demonstrate a clear dose-response relationship with profound clinical implications that deserve focused attention.The most compelling finding is the 53%relative increase in pregnancy rates between the higher and lower dose groups(23%vs.15%,P<0.001).This 8-percentage point absolute difference translates to a number needed to treat(NNT)of 12.5,meaning that for every 12-13 men treated with the higher dose instead of the lower dose,one additional pregnancy would be achieved.Given that male factor infertility contributes to approximately 50%of all infertility cases globally,this dose-response relationship has immediate clinical relevance.
基金Projects(52378392,52478390)supported by the National Natural Science Foundation of ChinaProject(2024J08213)supported by the Natural Science Foundation of Fujian Province,China+1 种基金Project(00387088)supported by the“Foal Eagle Program”Youth Top-notch Talent Project of Fujian Province,ChinaProject(GY-Z23072)supported by the Scientific Research Foundation of Fujian University of Technology,China。
文摘Gypsum rocks are highly susceptible to mechanical deterioration under the coupled effects of wet-dry(W-D)cycles and flow rates,which significantly influence the stability of underground excavations.Despite extensive research on the effects of W-D cycles,the coupling influence of flow rates and W-D cycles on gypsum rocks remains poorly understood.This study investigates the mechanical behavior and deterioration mechanisms of gypsum rocks subjected to varying W-D cycles and flow rate conditions.Axial compression tests,along with nuclear magnetic resonance(NMR)techniques,were employed to analyze the stress-strain response and microstructural changes.Based on the disturbed state concept(DSC)theory,a W-D deterioration model and a DSC-based constitutive model were developed to describe the degradation trends and mechanical responses of gypsum rocks under different conditions.The results demonstrate that key mechanical indices,elastic modulus,cohesion,uniaxial compressive strength(UCS),and internal friction angle,exhibit logarithmic declines with increasing W-D cycles,with higher flow rates accelerating the deterioration process.The theoretical models accurately capture the nonlinear compaction behavior,peak stress,and post-peak response of gypsum specimens.This study provides valuable insights for predicting the mechanical behavior of gypsum rocks and improving the stability assessments of underground structures under complex environmental conditions.
基金supported by the Anhui Provincial Natural Science Foundation(2408085QA031)the third author's work was supported by the National Natural Science Foundation of China(12001033).
文摘This paper studies the global existence and large-time behaviors of weak solutions to the kinetic particle model coupled with the incompressible Navier-Stokes equations in IR3.First,we obtain the global weak solution using the characteristic and energy methods.Then,under the small assumption of the mass of the particle,we show that the solutions decay at the algebraic time-decay rate.Finally,it is also proved that the above rate is optimal.It should be remarked that if the particle in the coupled system vanishes(i.e.f=O),our works coincide with the classical results by Schonbek[32](J Amer Math Soc,1991,4:423-449),which can be regarded as a generalization from a single fuid model to the two-phase fluid one.
文摘This study utilizes two complementary models,the Time-Varying Parameter Vector Autoregressive Diebold–Yilmaz(TVP-VAR-DY)and the Time-Varying Parameter Vector Autoregressive Barunik–Křehlik(TVP-VAR-BK),to investigate the dynamic volatility transmission between exchange rates and stock returns in major commodity-exporting and-importing countries.The analysis focuses on periods of quantitative easing(QE)and quantitative tightening(QT)from March 15,2020 to December 30,2022.The countries examined are Canada and Australia(major commodity exporters)and the UK and Germany(major commodity importers).An essential contribution of this paper is new empirical insights into the dynamics of stock market returns and the transmission of volatility between these markets and exchange rates during the QE and QT periods.The results reveal that causality primarily flows from stock markets to exchange rates,especially during the QT period across all investment horizons.The Toronto Stock Exchange(TSX)emerges as the principal net driver among the markets under study.Furthermore,the Canadian exchange rate(USDCAD)and the Australian Stock Exchange(ASX)are the most significantly affected indices within the network across various investment horizons(excluding the long-term).These findings underscore the importance for investors and policymakers to consider the interplay between exchange rates and stock market returns,particularly in the context of the QE and QT periods,as well as other economic,political,and health-related events.Our findings are relevant to various stakeholders,including governments,traders,portfolio managers,and multinationals.
文摘Acute cholangitis(AC)is a heterogeneous disease with considerable variation in clinical presentation and high medical costs.Although the overall mortality rate is decreasing.However,the mortality in severe AC ranged from 10%-30%due to sepsis,multi-organ failure,and systemic inflammatory response syndrome.Assessing the predictors of poor outcomes,including mortality,intensive care unit(ICU)admission,and hospital stay,is vital for early and effective intervention.We assessed the predictors of mortality and ICU admission in patients with AC.We conducted a literature search in PubMed/MEDLINE,Google Scholar,and Cochrane Library for relevant articles.The keywords used were acute cholangitis,biliary cholangitis,predictors,mortality,ICU admission,and Hospital stay.In addition,we assessed the role of early vs late endoscopic retrograde cholangiopancreatography on the outcomes.Old age,end-organ failure,red cell distribution width to albumin ratio,neutrophil-to-lymphocyte ratio,platelet-lymphocyte ratio,the need for ventilator support,diabetes,electrolyte imbalance,procalcitonin-to-albumin ratio,C-reactive protein-to-albumin,Glasgow Coma Scale,and systolic hypertension are predictors of poor outcomes in AC of varying etiology,and concurrent acute pancreatitis was not associated with ICU admission.
基金Project(2023YFC3009003) supported by the National Key R&D Program of ChinaProjects(52130409, 52121003, 52374249, 52204220) supported by the National Natural Science Foundation of ChinaProject(2024JCCXAQ01) supported by the Fundamental Research Funds for the Central Universities,China。
文摘In this study,a uniaxial cyclic compression test is conducted on coal-rock composite structures under two cyclic loads using MTSE45.104 testing apparatus to investigate the macro-mesoscopic deformation,damage behavior,and energy evolution characteristics of these structures under different cyclic stress disturbances.Three loading and unloading rates(LURs)are tested to examine the damage behaviors and energy-driven characteristics of the composites.The findings reveal that the energy-driven behavior,mechanical properties,and macro-micro degradation characteristics of the composites are significantly influenced by the loading rate.Under the gradual cyclic loading and unloading(CLU)path with a constant lower limit(path I)and the CLU path with variable upper and lower boundaries(path II),an increase in LURs from 0.05 to 0.15 mm/min reduces the average loading time by 32.39%and 48.60%,respectively.Consequently,the total number of cracks in the samples increases by 1.66-fold for path I and 1.41-fold for path II.As LURs further increase,the energy storage limit of samples expands,leading to a higher proportion of transmatrix and shear cracks.Under both cyclic loading conditions,a broader cyclic stress range promotes energy dissipation and the formation of internal fractures.Notably,at higher loading rates,cracks tend to propagate along primary weak surfaces,leading to an increased incidence of intermatrix fractures.This behavior indicates a microscopic feature of the failure mechanisms in composite structures.These results provide a theoretical basis for elucidating the damage and failure characteristics of coal-rock composite structures under cyclic stress disturbances.
基金funded by the Zhejiang Science and Technology Major Program on Agricultural New Variety Breeding,China(2021C02064-4)the Zhejiang Province“Three Rural and Nine Party”Science and Technology Cooperation Plan Project,China(2023SNJF002).
文摘Efficient nitrogen management is crucial for developing sustainable strategies aimed at enhancing yield while mitigating negative environmental impacts.However,research focusing on this aspect in the production of fresh maize is limited.Therefore,this study analyzed the effects of nitrogen application rates on the yields of 40 sweet and 44 waxy maize varieties at five sites in Zhejiang Province,China,from 2015 to 2019.The nitrogen application rates were categorized as either relatively high(RHN,>300 kg ha^(-1) for sweet maize and>320 kg ha^(-1) for waxy maize)or relatively low(RLN).An increase in nitrogen application rates significantly reduced nitrogen fertilizer partial productivity in both sweet and waxy maize(R^(2)=0.616,P<0.01;R^(2)=0.643,P<0.01),indicating that the optimum nitrogen application rates in this study might be the lowest values(160 kg ha^(-1) for sweet maize and 180 kg ha^(-1) for waxy maize).The kernel number per ear of sweet maize had a potentially more significant impact on fresh grain yield than the 1,000-fresh kernel weight under both RLN and RHN.In waxy maize,1,000-kernel weight contributed more to fresh grain yield under RLN,while kernel number per ear and 1,000-kernel weight cooperatively affected the yield under RHN.This study found that sweet maize required taller plant and ear heights,along with an optimal ear-plant height ratio,to enhance dry matter accumulation and increase source size,particularly under RLN,and to ultimately achieve a higher fresh grain yield.In contrast,a lower ear height and ear-plant height ratio in waxy maize probably contributed more to the greater kernel number and weight under RLN,likely due to a lower ear height which can reduce the distance between sink and source,enabling more efficient photoassimilate allocation to the ear.
文摘Quanto options allow the buyer to exchange the foreign currency payoff into the domestic currency at a fixed exchange rate. We investigate quanto options with multiple underlying assets valued in different foreign currencies each with a different strike price in the payoff function. We carry out a comparative performance analysis of different stochastic volatility (SV), stochastic correlation (SC), and stochastic exchange rate (SER) models to determine the best combination of these models for Monte Carlo (MC) simulation pricing. In addition, we test the performance of all model variants with constant correlation as a benchmark. We find that a combination of GARCH-Jump SV, Weibull SC, and Ornstein Uhlenbeck (OU) SER performs best. In addition, we analyze different discretization schemes and their results. In our simulations, the Milstein scheme yields the best balance between execution times and lower standard deviations of price estimates. Furthermore, we find that incorporating mean reversion into stochastic correlation and stochastic FX rate modeling is beneficial for MC simulation pricing. We improve the accuracy of our simulations by implementing antithetic variates variance reduction. Finally, we derive the correlation risk parameters Cora and Gora in our framework so that correlation hedging of quanto options can be performed.
基金Project(52409128)supported by the National Natural Science Foundation of ChinaProject(SDGZK2425)supported by the Opening Fund of State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering,China。
文摘The shape of underground chambers in deep mining varies due to their geological environment and intended use,which results in different failure modes under the influence of mining activities.However,the effect of chamber shape on the mechanism of structural integrity under dynamic load is still unclear.In this paper,granite samples with circular(C),rectangular(R),long ellipse(EL),and short ellipse(ES)holes were prepared.The dynamic mechanical response and cracking mechanism of granite were systematically analyzed using the split Hopkinson pressure bar(SHPB)test system and the hybrid finite and discrete element method(HFDEM).The results indicate that the dynamic strengths of granite with EL and ES represent the maximum and minimum values within the range of close strain rates,respectively.When EL granite is subjected to dynamic load,the axial stress concentration(in the load direction)is weak,and the transverse stress shows relative dispersion,which is the primary reason for its highest dynamic strength.The failure of granite with various holes primarily involves a tensile-shear mixed fracture,with relatively few pure typeⅡcracks.The chamber’s transverse span is the primary factor influencing the distribution range of the fracture area.
基金supported by the National Key R&D Program of China(2022YFC3003903)Natural Science Foundation of Beijing(Grant No.8222079)and of China(Grant No.42475014,U2442204)the Basic Research Fund of CAMS(2023Z001).
文摘This study investigates extreme rainfall episodes along the eastern foothills of the Taihang Mountains in North China from 30 July to 1 August 2023.It focuses on two types of extreme hourly rainfall rates(HRRs),i.e.,the maximum regionalaverage HRR and site-observed HRR,which exhibited sequential development over southern,middle,and northern key regions.These rainfall extremes occurred in an environment where a high-pressure barrier over North China prevented the intrusion of cold air masses from the north while a northward-moving typhoon remnant vortex and its associated low-level jet(LLJ)transported warm and moist airflow from the south.Two distinct echo evolution modes and convection initiation mechanisms are identified for the two types of extreme HRRs.The maximum regional-average HRR occurred when the LLJ arrived to the east of the key regions,while the maximum site-observed HRR occurred when the warmer vortex center influenced the regions.Taking the northern key region as a representation,at the time of the maximum regional-average HRR,slantwise ascent of the airflow along a warm-frontal-like boundary released energy related to symmetrical instability,resulting in stratiform rainfall with weak convective cores.The transport of locally initiated convection over the eastern plain region,where the atmospheric stratification was more potentially unstable,also significantly contributed.When the maximum site-observed HRR occurred,the terrain lifting of warm and moist southeast airflow led to intense convection over the mountain foothills.Overall,the passage of the warm-core typhoon remnant vortex and interaction with Taihang Mountains determined the timing and location of extreme HRRs across the key regions.
基金Supported by Oversea Project of National Natural and Science Foundationof China(30528005)RTOP Project of International RiceResearch Institute(IRRI)+1 种基金Grain High-yield Project of China(2004BA520A12)And 948 Introduction Project of the Ministry ofAgriculture(2003-Z53)~~
文摘Objective The aim was to elucidate the effects of N rates on rice canopy microclimate and community health so as to provide a sci- entific basis for studying the production potential in irrigated rice with healthy canopy. Method The effects of rice population structure traits under different N rates on rice canopy temperature, relative humidity （ RH）, light transmittance and sheath blight were studied by using Sunscan canopy analysis system and HOBO（ Pro Temp/RH IS logger）. Result The results showed that leaf area index, plant height and tiller number had significant effects on canopy cooling, RH enhancing and light reducing. Extremely significant multiple linear regression relationships existed among canopy day temperature, day RH, LAI and tiller number, and among light transmittance, tiller number and plant height. At flowering stage, per unit LAI could result in a day-maximum-temperature （Tmax） deceasing of 0.87℃ and a day-minimum-RH （RHmin） enhancing of 2.5% within canopy. Similarly, 100 plants per ms could respectively cause a Tmax deceasing of 1.23℃ and an RHmin enhancing of 3.3% in rice canopy. And per 10 cm plant height and 100 plants per m^2 could respectively reduce 9.3% and 7.8% of light in canopy. Conclusion Sheath blight disease index was significantly enhanced as the canopy day temperature decreased, day RH increased and light transmittance reduced. Bigger canopy from higher nitrogen level treatment leads to a more stable canopy microclimate with little changes in temperature and RH during day and night, which has the risk of worsening canopy health. Thus, moderately controlling the space development of canopy is the basis of constructing healthy canopy in rice.
基金the European Union's Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No 101034425 for the project titled A2M2TECHThe Scientific and Technological Research Council of Türkiye (TUBITAK) with grant No 120C158 for the same A2M2TECH project under the TUBITAK's 2236/B program
文摘Recent advances in additive manufacturing have enabled the construction of metallic lattice structures with tailored mechanical and functional properties.One potential application of metallic lattice struc-tures is in the impact load mitigation where an external kinetic energy is absorbed by the deformation/crushing of lattice cells.This has motivated a growing number of experimental and numerical studies,recently,on the crushing behavior of additively produced lattice structures.The present study overviews the dynamic and quasi-static crushing behavior of additively produced Ti64,316L,and AlSiMg alloy lattice structures.The first part of the study summarizes the main features of two most commonly used additive processing techniques for lattice structures,namely selective-laser-melt(SLM)and electro-beam-melt(EBM),along with a description of commonly observed process induced defects.In the second part,the deformation and strain rate sensitivities of the selected alloy lattices are outlined together with the most widely used dynamic test methods,followed by a part on the observed micro-structures of the SLM and EBM-processed Ti64,316L and AlSiMg alloys.Finally,the experimental and numerical studies on the quasi-static and dynamic compression behavior of the additively processed Ti64,316L,and AlSiMg alloy lattices are reviewed.The results of the experimental and numerical studies of the dynamic properties of various types of lattices,including graded,non-uniform strut size,hollow,non-uniform cell size,and bio-inspired,were tabulated together with the used dynamic testing methods.The dynamic tests have been noted to be mostly conducted in compression Split Hopkinson Pressure Bar(SHPB)or Taylor-and direct-impact tests using the SHPB set-up,in all of which relatively small-size test specimens were tested.The test specimen size effect on the compression behavior of the lattices was further emphasized.It has also been shown that the lattices of Ti64 and AlSiMg alloys are relatively brittle as compared with the lattices of 316L alloy.Finally,the challenges associated with modelling lattice structures were explained and the micro tension tests and multi-scale modeling techniques combining microstructural characteristics with macroscopic lattice dynamics were recommended to improve the accuracy of the numerical simulations of the dynamic compression deformations of metallic lattice structures.
基金support from the National Natural Science Foundation of China(Grant No.61901295)the Nanchang Microsystem Institute of Tianjin University.
文摘Accurately correlating the sweating rate and the concentration of biomarkers in sweat is essential in many sweat-based diagnostic applications.These two measurements are always done simultaneously in wearable sweat sensing platforms.However,concentration measurements of biomarkers are always delayed on the timeline compared with their production,whereas there is no such delay for sweating rate.Thus,a timeline mismatch exists between these two measurements.This means that the concentration vs rate correlation constructed on the basis of such measurements will deviate from the actual correlation.This study demonstrates the existence of this mismatch and explains its cause using sweat Na^(+)measurements.It also proposes an effective approach that applies a point-by-point compensation for the delay between Na+measurements and the real-time sweating rates,such that the data on the repositioned concentration vs time curve correspond to exactly the same point on the timeline as their production.A vison sensor is developed to measure the sweating rate with high accuracy at a frequency of more than 0.1 Hz.Off-body and on-body measurements of sweating rate and Na^(+)concentration are carried out,and concentration–rate correlations are constructed using both measured and repositioned concentration curves.The least squares and random forest methods are employed to fit the constructed correlations and evaluate the reliability of the proposed approach.The use of the repositioned concentration curve gives a constructed correlation that is much closer to the actual one.This study indicates the necessity to rearrange sensor-measured biomarker concentration vs time curves when correlations of concentration with sweating rate need to be constructed and proposes a practical point-by-point data repositioning strategy for doing so.The results presented here will benefit the study of sweat biomarkers with unclear correlations with sweating rate,as well as providing a basis for the development of more reliable sweat-based diagnostic methods.
基金supported by the Kushlan Fund from the University of Miami Department of Biology.
文摘South Florida’s natural forest ecosystems,including pine rocklands and hardwood hammocks,are threatened by land use change and urbanization,invasive species,and climate change.It is critical to understand the responses of these ecosystems to anthropogenic disturbances to conserve the remnants of the USA natural subtropical forests.Using dendrochronology,long-term growth patterns were characterized in three dominant native tree species:Bursera simaruba,Swietenia mahagoni,and Pinus elliottii.Core samples were collected from>30 individuals of each species in hardwood hammocks(B.simaruba and S.mahagoni)and pine rocklands(P.elliottii)to examine growth patterns.Relationships between annual tree growth rates and climatic variables were assessed to address three questions:(1)What are the climatic drivers of growth in these three South Florida tree species?(2)Are their growth rates stable or changing through time?and(3)Are tree growth rates affected by urbanization?Standardized growth rates of the three species have changed through time,with small young trees showing accelerated growth through time,whereas larger,older trees showed declining growth rates.S.mahagoni and B.simaruba grew faster in urbanized parks than in more natural parks,whereas P.elliottii grew slower in urban parks.There were positive correlations between tree growth and the current year’s fall precipitation and no discernable effects of the current year’s monthly temperatures on growth rates of any of the species.These results suggest that the foundational tree species of the southern USA endangered pine rocklands and hardwood hammocks may be vulnerable to ongoing changes in precipitation and temperature as well as other environmental effects associated with urbanization.
基金supported by the National Natural Science Foundation of China[Grant No.:32070438].
文摘Understanding the molecular relevance of metabolic rate(MR)is crucial for unveiling the mechanisms driving the evolution of animals.In this study,we investigated the association between mitochondrial DNA characteristics and both resting and maximal MRs in conjunction with life-history traits among 139 species of teleost fish,We gathered fish MR data from various sources and procured sequences of 13 mitochondrial protein-encoding genes.We calculated the absolute substitution rate for entire nucleotide sequences and 4-fold degenerate sites of each gene,along with encoding amino acid sequences.Using the phylogenetic comparative method,we then explored the associations between MR and mitochondrial DNA absolute substitution rate.Additionally,we screened MR-associated single nucleotide variants in mitochondrial DNA.The findings indicate no positive correlation between MRs and any substitution rate values of both combined sequences and individual mitochondrial protein-coding genes,refuting the MR hypothesis.Instead,both maximum body size and longevity correlated negatively with molecular substitution rates,suggesting their influences on both mutation and fixation within mitochondrial genes in fish.Results also revealed significant correlations between base variation at ATP6_169 and both resting MR and maximum MR,identifying the unique ATP6_169G in Scombridae fish,which results in an extremely low isoelectric point(pl)value of the ATP6 protein.Considering its functional significance,the ATP6_169G in Scombridae fish might link to their lifestyle characterized by fast locomotion and high metabolic demands alongside a slower molecular evolutionary rate.
