BACKGROUND Non-ST segment elevation myocardial infarction(NSTEMI)poses significant challenges in clinical management due to its diverse outcomes.Understanding the prognostic role of hematological parameters and derive...BACKGROUND Non-ST segment elevation myocardial infarction(NSTEMI)poses significant challenges in clinical management due to its diverse outcomes.Understanding the prognostic role of hematological parameters and derived ratios in NSTEMI patients could aid in risk stratification and improve patient care.AIM To evaluate the predictive value of hemogram-derived ratios for major adverse cardiovascular events(MACE)in NSTEMI patients,potentially improving clinical outcomes.METHODS A prospective,observational cohort study was conducted in 2021 at the Internal Medicine Clinic of the University Hospital in Tuzla,Bosnia and Herzegovina.The study included 170 patients with NSTEMI,who were divided into a group with MACE and a control group without MACE.Furthermore,the MACE group was subdivided into lethal and non-lethal groups for prognostic analysis.Alongside hematological parameters,an additional 13 hematological-derived ratios(HDRs)were monitored,and their prognostic role was investigated.RESULTS Hematological parameters did not significantly differ between non-ST segment elevation myocardial infarction(NSTEMI)patients with MACE and a control group at T1 and T2.However,significant disparities emerged in HDRs among NSTEMI patients with lethal and non-lethal outcomes post-MACE.Notably,neutrophil-to-lymphocyte ratio(NLR)and platelet-to-lymphocyte ratio(PLR)were elevated in lethal outcomes.Furthermore,C-reactive protein-to-lymphocyte ratio(CRP/Ly)at T1(>4.737)demonstrated predictive value[odds ratio(OR):3.690,P=0.024].Both NLR at T1(>4.076)and T2(>4.667)emerged as significant predictors,with NLR at T2 exhibiting the highest diagnostic performance,as indicated by an area under the curve of 0.811(95%CI:0.727-0.859)and OR of 4.915(95%CI:1.917-12.602,P=0.001),emphasizing its important role as a prognostic marker.CONCLUSION This study highlights the significant prognostic value of hemogram-derived indexes in predicting MACE among NSTEMI patients.During follow-up,NLR,PLR,and CRP/Ly offer important insights into the inflammatory processes underlying cardiovascular events.展开更多
Publisher Correction to:Journal of Forestry Research(2025)36:29 https://doi.org/10.1007/s11676-025-01823-0 In Fig.4c of this article,the lower part of the figure was unintentionally cropped and incomplete during the p...Publisher Correction to:Journal of Forestry Research(2025)36:29 https://doi.org/10.1007/s11676-025-01823-0 In Fig.4c of this article,the lower part of the figure was unintentionally cropped and incomplete during the publisher's production process.The published incorrect version and the corrected version of Fig.4 are given below.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 Patients with type 2 diabetes mellitus(T2DM)face a heightened risk of future cardiovascular events.It is therefore important to stratify these patients according to their future cardiovascular event risk to...BACKGROUND Patients with type 2 diabetes mellitus(T2DM)face a heightened risk of future cardiovascular events.It is therefore important to stratify these patients according to their future cardiovascular event risk to allow early intervention and improve prognosis.Recent proposals have indicated that nontraditional lipoprotein ratios may be superior predictors of cardiovascular events compared to traditional lipid parameters.However,further evidence is required for widespread clinical ap-plication.AIM To elucidate the associations of nontraditional lipoprotein ratios with future cardiovascular events in patients with T2DM.METHODS This study performed post-hoc analysis of data obtained during a clinical trial involving 10182 participants.To ascertain the correlations between nontraditional lipoprotein ratios and future cardiovascular events,including major adverse cardiovascular events(MACEs)and congestive heart failure(CHF).We employed univariable and multivariable-adjusted Cox proportional hazards regression models.Potential dose-response relationships and threshold values were explored by conducting restricted cubic spline analyses and two-piecewise linear regression models.Possible relevant interactions influencing independent relationships were tested using subgroup and interaction analyses.RESULTS After adjustment for confounding factors,all nontraditional lipoprotein ratios studied were strongly associated with MACE risk in patients with T2DM.In comparison with patients in the lowest quartile,the hazard ratios(95%confidence intervals)of those in the highest quartile were 1.50(1.29-1.73),1.51(1.30-1.74),1.50(1.29-1.73),and 1.30(1.12-1.50)for total cholesterol/high-density lipoprotein cholesterol(HDL-C),low-density lipoprotein cholesterol/HDL-C,non-HDL-C/HDL-C,and remnant cholesterol/HDL-C,respectively.Similar findings were noted for CHF.Dose-response relationships between nontraditional lipoprotein ratios and MACE were observed,with threshold values of 7.29,6.29,and 2.15 for total cholesterol/HDL-C,non-HDL-C/HDL-C,and remnant cholesterol/HDL-C,respectively.However,no notable dose-response relationships were detected between nontraditional lipoprotein ratios and CHF.CONCLUSION Elevated nontraditional lipoprotein ratios may independently predict the risk of MACE and CHF in patients with T2DM.展开更多
A high-speed train travelling from the open air into a narrow tunnel will cause the“sonic boom”at tunnel exit.When the maglev train’s speed reaches 600 km/h,the train-tunnel aerodynamic effect is intensified,so a n...A high-speed train travelling from the open air into a narrow tunnel will cause the“sonic boom”at tunnel exit.When the maglev train’s speed reaches 600 km/h,the train-tunnel aerodynamic effect is intensified,so a new mitigation method is urgently expected to be explored.This study proposed a novel asymptotic linear method(ALM)for micro pressure wave(MPW)mitigation to achieve a constant gradient of initial c ompression waves(ICWs),via a study with various open ratios on hoods.The properties of ICWs and MPWs under various open ratios of hoods were analyzed.The results show that as the open ratio increases,the MPW amplitude at the tunnel exit initially decreases before rising.At the open ratio of 2.28%,the slope of the ICW curve is linearly coincident with a supposed straight line in the ALM,which further reduces the MPW amplitude by 26.9%at 20 m and 20.0%at 50 m from the exit,as compared to the unvented hood.Therefore,the proposed method effectively mitigates MPW and quickly determines the upper limit of alleviation for the MPW amplitude at a fixed train-tunnel operation condition.All achievements provide a ne w potential measure for the adaptive design of tunnel hoods.展开更多
BACKGROUND An efficient index holds the potential to predict rectal cancer prognosis.AIM To investigate the impact of neutrophil-to-lymphocyte ratio(NLR),platelet-tolymphocyte ratio(PLR),and monocyte-to-lymphocyte rat...BACKGROUND An efficient index holds the potential to predict rectal cancer prognosis.AIM To investigate the impact of neutrophil-to-lymphocyte ratio(NLR),platelet-tolymphocyte ratio(PLR),and monocyte-to-lymphocyte ratio(MLR)on rectal cancer prognosis.METHODS This retrospective study involved 180 patients with rectal cancer from the Changzhi People’s Hospital of Shanxi Province.A 2-mL blood sample was collected at 24 h preoperatively and 72 h postoperatively to measure neutrophils,lymphocytes,platelets,and monocytes using an automatic blood analyzer.Preoperative and postoperative NLR,PLR,and MLR were compared.Patients were followed up for 12 months and categorized into good and poor prognosis groups.A receiver operating characteristic curve was constructed to analyze their predictive values.RESULTS The NLR,PLR,and MLR values were significantly lower post-surgery(P<0.05).A total of 152 and 28 patients were categorized in the good and poor prognosis groups,respectively.Patients with poor prognoses exhibited slightly higher postoperative NLR,PLR,and MLR values than those with good prognoses(P<0.05).Receiver operating characteristic analysis showed that the area under the curve for NLR,PLR,and MLR was 0.828 with a sensitivity and specificity of 89.29%and 90.79%,respectively.These values were higher than individual NLR(area under the curve:0.660,sensitivity:67.86%,specificity:54.61%),PLR(0.668,75.00%,55.30%),and MLR(0.635,60.71%,48.03%),all showing statistically significant differences(P<0.05),effectively predicting patient outcomes.CONCLUSION The findings of this study indicated that NLR,PLR,and MLR values of patients with rectal cancer can be used to effectively predict the outcome of patients.展开更多
Driver distraction is a leading cause of traffic accidents,with fatigue being a significant contributor.This paper introduces a novel method for detecting driver distraction by analyzing facial features using machine ...Driver distraction is a leading cause of traffic accidents,with fatigue being a significant contributor.This paper introduces a novel method for detecting driver distraction by analyzing facial features using machine deep learning and 68 face model.The proposed system assesses driver tiredness by measuring the distance between key facial landmarks,such as the distance between the eyes and the angle of the mouth,to evaluate signs of drowsiness or disengagement.Real-time video feed analysis allows for continuous monitoring of the driver’s face,enabling the system to detect behavioral cues associated with distraction,such as eye closures or changes in facial expressions.The effectiveness of this method is demonstrated through a series of experiments on a dataset of driver videos,which proves that the approach can accurately assess tiredness and distraction levels under various driving conditions.By focusing on facial landmarks,the system is computationally efficient and capable of operating in real-time,making it a practical solution for in-vehicle safety systems.This paper discusses the system’s performance,limitations,and potential for future enhancements,including integration with other in-vehicle technologies to provide comprehensive driver monitoring.展开更多
Much of the research has focused on identifying bridge frequencies for health monitoring,while the bridge damping ratio also serves as an important factor in damage detection.This study presents an enhanced method for...Much of the research has focused on identifying bridge frequencies for health monitoring,while the bridge damping ratio also serves as an important factor in damage detection.This study presents an enhanced method for identifying bridge damping ratios using a two-axle,three-mass test vehicle,relying on wheel responses captured by only two mounted sensors.Damping ratio estimation formulas are derived using both the Hilbert Transform(HT)and Wavelet Transform(WT),with a consistent formulation that confirms accurate estimation is achievable with minimal instrumentation,particularly when addressing the support effect.A comparative analysis of the two signal processing techniques reveals the superior performance of WT in identifying bridge damping ratios.The effectiveness of the proposed procedure and formulas is validated through a detailed parametric study,demonstrating robustness across bridges with varying modal damping ratios and different spans using minimal sensors.Moreover,the present study shows that responses from only the first two spans of a multi-span bridge are sufficient for reliable damping estimation,underscoring the practicality and scalability of the procedure for structural health monitoring applications.展开更多
Cemented tailings backfill(CTB)is a crucial support material for ensuring the long-term stability of underground goafs.A comprehensive understanding of its compressive mechanical behavior is essential for improving en...Cemented tailings backfill(CTB)is a crucial support material for ensuring the long-term stability of underground goafs.A comprehensive understanding of its compressive mechanical behavior is essential for improving engineering safety.Although extensive studies have been conducted on the uniaxial compressive properties of CTB,damage constitutive models that effectively capture its damage evolution process remain underdeveloped,and its failure mechanisms are not yet fully clarified.To address these gaps,this study conducted systematic uniaxial compression tests on CTB specimens prepared with varying cement-tailings ratios.The results revealed distinct compaction and softening phases in the stress−strain curves.A lower cement-tailings ratio significantly reduced the strength and deformation resistance of CTB,along with a decrease in elastic energy accumulation at peak stress and dissipation energy in the post peak stage.Based on these findings,a modified damage constitutive model was developed by introducing a correction factor,enabling accurate simulation of the entire uniaxial compression process of CTB with different cement-tailings ratios.Comparative analysis with classical constitutive models validated the proposed model’s accuracy and applicability in describing the compressive behavior of CTB.Furthermore,particle size distribution and acoustic emission tests were employed to investigate the influence of cement-tailings ratio on failure mechanisms.The results indicated that a lower cement-tailings ratio leads to coarser particle sizes,which intensify shear-related acoustic emission signals and ultimately result in more pronounced macroscopic shear failure.This study provides theoretical support and practical guidance for the optimal design of CTB mix ratios.展开更多
Flow characteristics around a wall-mounted square cylinder have been numerically simulated at aspect ratios (AR) ranging from 4 to 7 at Re =10 000. Four turbulence models have been compared in terms of drag coefficien...Flow characteristics around a wall-mounted square cylinder have been numerically simulated at aspect ratios (AR) ranging from 4 to 7 at Re =10 000. Four turbulence models have been compared in terms of drag coefficient (C_D). The closest result has been provided by two turbulence models, namely, k-ε Realizable and k ?ω Shear Stress Transport (SST). Hence, these models were utilized to present the flow patterns of pressure distributions, turbulent kinetic energy values, velocity magnitude values with streamlines, streamwise velocity components, crossstream velocity components and spanwise velocity components on different planes. Flow stagnation has been attained in front of the cylinder. Pressure values peaked for the upstream region. Over the cylinders, the tip vortex structure was dominant owing to the influence of the free end. Flow separation from the top front edge of the body has been obtained. The dividing streamline affected by the flow separation was highly effective in the wake region and moved nearer to the body when the aspect ratio was decreased;the reason was the wake shrinkage owing to the decreasing aspect ratio. Upwash and downwash have been seen in the cylinder wake. These two models presented similar flow patterns and drag coefficients. These drag coefficients are in good agreement with those in previous studies.展开更多
Polysynthetic twinned(PST)TiAl single crystal specifically refers to a fully lamellar TiAl single crystal with parallel phase interfaces and twin interfaces grown by directional solidification.In this paper,PST single...Polysynthetic twinned(PST)TiAl single crystal specifically refers to a fully lamellar TiAl single crystal with parallel phase interfaces and twin interfaces grown by directional solidification.In this paper,PST single crystals with different phase ratios are obtained by annealing at specific temperatures and holding times.The results show that the diffusion rates of Ti and Al elements at various temperatures directly trigger and propel the surface recrystallization and variation in the internal phase ratio.When the temperature is lower than 1448 K,the diffusion rate of Ti is obviously higher than that of Al,which causes one denseα_(2)recrystallized layer to form on the surface of TiAl single crystals.Meanwhile,as more Ti elements migrate to the surface,theα_(2)phase ratio inside the TiAl single crystal thereby decreases.When the temperature exceeds 1448 K,the diffusion rate of Al gradually reverses to exceed that of Ti,which forms the surface sandwiched recrystallization dominated byγphase and simultaneously increasesα_(2)phase ratio inside the TiAl single crystal.The variation in the two-phase ratio directly induces a significant change in the lamellae thickness,which exhibits different tensile behaviors of PST-TiAl single crystal.When theα_(2)phase content is less than 20%,widerγlamellae make it easier for dislocations to be activated within its lamellae and continuously move across theγ/α_(2)interfaces,thereby obtaining better tensile plasticity.As theα_(2)phase content exceeds 30%,finerγlamellae inhibit the dislocation initiation,resulting in the fracture occurrence of TiAl single crystal before yielding.No matter how the phase ratio changes,the crack preferentially initiates withinα_(2)lamellae.However,the crack propagation follows different paths based on variousγlamella thicknesses.The fracture mode of PST-TiAl single crystal also changes from shear fracture along slip bands within theγlamella to brittle fracture along the{1¯100}planes withinα_(2)lamella.展开更多
This study employed a wet impregnation method to synthesize five types of Cu/HZSM-5 adsorbents with Si/Al ratios of 25,50,85,200,and 300,used for the removal of H_(2)S in lowtemperature,low-oxygen environments.The imp...This study employed a wet impregnation method to synthesize five types of Cu/HZSM-5 adsorbents with Si/Al ratios of 25,50,85,200,and 300,used for the removal of H_(2)S in lowtemperature,low-oxygen environments.The impact of different Si/Al ratios on the adsorption oxidative performance of Cu_(30)/HZSM-5–85 adsorbents was investigated.According to the performance test results,Cu_(30)/HZSM-5–85 exhibited the highest breakthrough capacity,reaching 231.75 mg H_(2)S/g_(sorbent).Cu/HZSM-5 sorbent maintains a strong ability to remove H_(2)S even under humid conditions and shows excellent water resistance.XRD,BET,and XPS results revealed that CuO is the primary active species,with Cu_(30)/HZSM-5–85 having the largest surface area and highest CuO content,providing more active sites for H_(2)S adsorption.H_(2)-TPR and O_(2)-TPD results confirmed that Cu_(30)/HZSM-5–85 sorbent exhibits outstanding redox properties and oxygen storage capacity,contributing to excellent oxygen transferability in the molecular sieve adsorption-oxidation process.With notable characteristics such as a large surface area,high desulfurization efficiency,and water resistance,Cu_(30)/HZSM-5–85 sorbents hold significant importance for industrial applications.展开更多
Background:Diabetes mellitus(DM)is a prevalent chronic metabolic condition characterized by high blood sugar levels,resulting from insufficient insulin production or ineffective insulin use,posing substantial global h...Background:Diabetes mellitus(DM)is a prevalent chronic metabolic condition characterized by high blood sugar levels,resulting from insufficient insulin production or ineffective insulin use,posing substantial global health issues.Research on the relationship between glycemic status and the ratio of neutrophils to lymphocytes(NLR)and monocytes to lymphocytes(MLR)is limited.This study aimed to fill these knowledge gaps by examining the connection between DM and inflammatory markers within the Asir region.Methods:Data from 3545 participants were retrospectively analyzed.The dataset,gathered between 2021 and 2023,comprises 38 laboratory tests obtained from the Future Lab Pioneer database.The study's inclusion criteria focused on diabetes profile tests(glycated hemoglobin[HbA1c]and fasting blood glucose[FBG])and manually computed inflammatory markers(NLR and MLR),which were stratified by age and sex.Results:This study demonstrated significant differences in NLR levels compared with FBG levels across all adult age groups and adult female participants(p<0.0001),as well as among all elderly age groups(p=0.0006)and elderly women(p=0.01).MLR levels were significant in all adult age groups(p=0.04)and in adult women(p=0.02).When NLR and MLR were compared to HbA1c levels,a significant difference in the mean NLR was found in adult women(p=0.005).Additionally,the mean MLR levels were significant in all adult age groups(p=0.04)and adult women(p=0.02).Conclusion:Although a larger sample size is necessary for this research,the results indicate that NLR and MLR could serve as valuable indicators for evaluating inflammation in people with disrupted glucose metabolism,particularly in adult and female populations.展开更多
Solar sailing is a promising propellant-free approach to propelling spacecraft in space.However, the propelling efficiency of conventional solar sail spacecraft is limited by their areato-mass ratios. This paper propo...Solar sailing is a promising propellant-free approach to propelling spacecraft in space.However, the propelling efficiency of conventional solar sail spacecraft is limited by their areato-mass ratios. This paper proposes a novel design of micro solar sails with area-to-mass ratios above 100 m^(2)/kg for next-generation chip-scale spacecraft. Bilayer thin films developed by Microelectromechanical Systems(MEMS) technologies were patterned into grid microstructures, and theoretical analysis of a sail prototype was conducted. The electro-thermal and thermo-mechanical models of the solar sail in geospace were established by taking effects of Joule heating, solar radiation, and thermal re-emission into consideration, enabling rapid prediction of its threedimensional(3-D) reconfiguration from the as-released two-dimensional(2-D) microstructure.Adjustment of the Chip Sail's acceleration arising from the sail's morphing was also analytically modeled. Fabrication and characterization of the sail prototype made of multiple Al/Ni_(50)Ti_(50) bilayer beams were accomplished. In-situ SEM imaging of the sail prototype in vacuum chamber witnessed an active and continuous 3-D reconfiguration under Joule heating, and over 90° deformation was detected by applying a DC voltage of 0.078 V. Theoretical and experimental work on the solar sail with at least 10 times higher area-to-mass ratios than conventional ones will lay a solid foundation for efficient solar sailing.展开更多
The yield ratios of neutron-proton(R(n/p))and^(3)H-^(3)He(R(^(3)H∕^(3)He))with reduced rapidity from 0 to 0.5 were simulated at 50 MeV/u even-even ^(36−56)Ca+^(40)Ca,even-even ^(48−78)Ni+^(58)Ni,and ^(100−139)Sn(ever...The yield ratios of neutron-proton(R(n/p))and^(3)H-^(3)He(R(^(3)H∕^(3)He))with reduced rapidity from 0 to 0.5 were simulated at 50 MeV/u even-even ^(36−56)Ca+^(40)Ca,even-even ^(48−78)Ni+^(58)Ni,and ^(100−139)Sn(every third isotopes)+112 Sn for full reduced impact parameters using the isospin-dependent quantum molecular dynamics(IQMD)model.The neutron and proton density distributions and root-mean-square radii of the reaction systems were obtained using the Skyrme-Hartree-Fock model,which was used for the phase space initialization of the projectile and target in IQMD.We defined the unified neutron skin thickness asΔRnp=<r^(2)>^(1∕2) n−<r^(2)>^(1∕2)p,which was negative for neutron-deficient nuclei.The unifiedΔRnp values for nuclei with the same relative neutron excess from different isotopic chains were nearly equal,except for extreme neutron-rich isotopes,which is a type of scaling behavior.The yield ratios of the three isotopic chain-induced reactions,which depended on the reduced impact parameter and unified neutron skin thickness,were studied.The results showed that both R(n/p)and R(^(3)H∕^(3)He)decreased with a reduced impact parameter for extreme neutron-deficient isotopes;however,they increased with reduced impact parameters for extreme neutron-rich isotopes,and increased with theΔRnp of the projectiles for all reduced impact parameters.In addition,a scaling phenomenon was observed betweenΔR np and the yield ratios in peripheral colli-sions from different isotopic chain projectiles(except for extreme neutron-rich isotopes).Thus,R(n/p)and R(^(3)H∕^(3)He)from peripheral collisions were suggested as experimental probes for extracting the neutron or proton skin thicknesses of non-extreme neutron-rich nuclei from different isotopic chains.展开更多
This study is a contribution to improving rice productivity on acidic plateau soils of the tropical rainforest zone. It is based on taking into account the cationic balances of the soil in order to optimize the phosph...This study is a contribution to improving rice productivity on acidic plateau soils of the tropical rainforest zone. It is based on taking into account the cationic balances of the soil in order to optimize the phosphorus (P) nutrition of rice on these acidic soils, where this nutrient constitutes a limiting factor for agricultural production. Three (3) pot trials were conducted in Adiopodoumé in the forested south of Côte d’Ivoire. The interactive effects of calcium carbonate (0, 25, 50 and 75 kg Ca ha<sup>−1</sup>) and magnesium sulfate (0, 25, 50 and 75 kg Mg ha<sup>−1</sup>) were evaluated on the response of NERICA 5 rice at doses 0, 25, 50 and 75 kg P ha<sup>−1</sup> of natural phosphate from Togo, applied only once at the start of the experiment. Additional fertilizers of nitrogen (N) (100 kg N ha<sup>−1</sup>) and potassium (K) (50 kg KCl ha<sup>−1</sup>) were added to each of the tests in a split-plot device. The test results revealed a paddy production potential of approximately 3 to 5 t⋅ha<sup>−1</sup> for NERICA 5 on an acidic soil, under the effect of the interaction of P, Ca and Mg. The quadratic response of rice yield to the doses of these fertilizers would be more dependent on their balance, itself influenced by Ca nutrition. For the sustainability and maintenance of rice production in agro-ecology studied, it was recommended doses of 38 kg Ca ha<sup>−1</sup>, 34 kg Mg ha<sup>−1</sup> in a Ca/Mg ratio (1/1) with intakes of 41 kg P ha<sup>−1</sup>, overall in a ratio 1/1/1 (P/Ca/Mg) more favorable to the availability of free iron considered a guiding element of mineral nutrition. Thus, these promising results should be confirmed in a real environment for better management of the fertilization of rice cultivated on acidic plateau soils in Côte d’Ivoire.展开更多
In an effort to investigate and quantify the patterns of local scour,researchers embarked on an in-depth study using a systematic experimental approach.The research focused on the effects of local scour around a set o...In an effort to investigate and quantify the patterns of local scour,researchers embarked on an in-depth study using a systematic experimental approach.The research focused on the effects of local scour around a set of four piles,each subjected to different hydromechanical conditions.In particular,this study aimed to determine how different attack angles—the angles at which the water flow impinges on the piles,and gap ratios—the ratios of the spacing between the piles to their diameters,influence the extent and nature of scour.A comprehensive series of 35 carefully designed experiments were orchestrated,each designed to dissect the nuances in how the gap ratio and attack angle might contribute to changes in the local scour observed at the base of pile groups.During these experimental trials,a wealth of local scour data were collected to support the analysis.These data included precise topographic profiles of the sediment bed around the pile groups,as well as detailed scour time histories showing the evolution of scour at strategic feature points throughout the test procedure.The analysis of the experimental data provided interesting insights.The study revealed that the interplay between the gap ratio and the attack angle had a pronounced influence on the scouring dynamics of the pile groups.One of the key observations was that the initial phases of scour,particularly within the first hour of water flow exposure,were characterized by a sharp increase in the scour depth occurring immediately in front of the piles.After this initial rapid development,the scour depth transitioned to a more gradual change rate.In contrast,the scour topography around the piles continuously evolved.This suggests that sediment displacement and the associated sculpting of the seabed around pile foundations are sustained and progressive processes,altering the underwater landscape over time.The results of this empirical investigation have significant implications for the design and construction of offshore multi-pile foundations,providing a critical reference for engineers and designers to estimate the expected scour depth around such structures,which is an integral part of decisions regarding foundation design,selection of structural materials,and implementation of scour protection measures.展开更多
This study conducts both numerical and empirical assessments of thermal transfer and fluid flow characteristics in a Solar Air Collector(SAC)using a Delta Wing Vortex Generator(DWVG),and the effects of different heigh...This study conducts both numerical and empirical assessments of thermal transfer and fluid flow characteristics in a Solar Air Collector(SAC)using a Delta Wing Vortex Generator(DWVG),and the effects of different height ratios(Rh=0.6,0.8,1,1.2 and 1.4)in delta wing vortex generators,which were not considered in the earlier studies,are investigated.Energy and exergy analyses are performed to gain maximum efficiency.The Reynolds number based on the outlet velocity and hydraulic diameter falls between 4400 and 22000,corresponding to the volume flow rate of 5.21–26.07 m^(3)/h.It is observed that the delta wing vortex generators with a higher height ratio yield maximum heat transfer enhancement and overall enhancement ratio.The empirical and numerical findings demonstrate that the exergy and thermal efficiencies decline in a specific range.TheNusselt number,pressure drop,energy,and exergy efficiencies enhance with rising Reynolds number,although the friction coefficient diminishes.The maximum heat transfer enhancement is 57%.According to the evaluation of exergy efficiency,the greatest efficiency of 31.2%is obtained at Rh=1.4 and Reynolds number 22000.展开更多
Background: The signal-to-noise ratio (SNR) is recognized as an index of measurements reproducibility. We derive the maximum likelihood estimators of SNR and discuss confidence interval construction on the difference ...Background: The signal-to-noise ratio (SNR) is recognized as an index of measurements reproducibility. We derive the maximum likelihood estimators of SNR and discuss confidence interval construction on the difference between two correlated SNRs when the readings are from bivariate normal and bivariate lognormal distribution. We use the Pearsons system of curves to approximate the difference between the two estimates and use the bootstrap methods to validate the approximate distributions of the statistic of interest. Methods: The paper uses the delta method to find the first four central moments, and hence the skewness and kurtosis which are important in the determination of the parameters of the Pearsons distribution. Results: The approach is illustrated in two examples;one from veterinary microbiology and food safety data and the other on data from clinical medicine. We derived the four central moments of the target statistics, together with the bootstrap method to evaluate the parameters of Pearsons distribution. The fitted Pearsons curves of Types I and II were recommended based on the available data. The R-codes are also provided to be readily used by the readers.展开更多
Technologies for reducing corn leaf burn caused by foliar spray of urea-ammonium nitrate (UAN) during the early growing season are limited. A field experiment was carried out to evaluate the effects of humic acid on c...Technologies for reducing corn leaf burn caused by foliar spray of urea-ammonium nitrate (UAN) during the early growing season are limited. A field experiment was carried out to evaluate the effects of humic acid on corn leaf burn caused by foliar spray of undiluted UAN solution on corn canopy at Jackson, TN in 2018. Thirteen treatments of the mixtures of UAN and humic acid were evaluated at V6 of corn with different UAN application rates and different UAN/humic acid ratios. Leaf burn during 1 2, 3, 4, 5, 6, 7, and 14 days after UAN foliar spray significantly differed between with or without humic acid addition. The addition of humic acid to UAN significantly reduced leaf burn at each UAN application rate (15, 25, and 35 gal/acre). The reduction of leaf burn was enhanced as the humic acid/UAN ratio went up from 10% to 30%. Leaf burn due to foliar application of UAN became severer with higher UAN rates. The linear regression of leaf burn 14 days after application with humic acid/UAN ratio was highly significant and negative. However, the linear regression of leaf burn 14 days after application with the UAN application rate was highly significant and positive. In conclusion, adding humic acid to foliar-applied UAN is beneficial for reducing corn leaf burn during the early growing season.展开更多
文摘BACKGROUND Non-ST segment elevation myocardial infarction(NSTEMI)poses significant challenges in clinical management due to its diverse outcomes.Understanding the prognostic role of hematological parameters and derived ratios in NSTEMI patients could aid in risk stratification and improve patient care.AIM To evaluate the predictive value of hemogram-derived ratios for major adverse cardiovascular events(MACE)in NSTEMI patients,potentially improving clinical outcomes.METHODS A prospective,observational cohort study was conducted in 2021 at the Internal Medicine Clinic of the University Hospital in Tuzla,Bosnia and Herzegovina.The study included 170 patients with NSTEMI,who were divided into a group with MACE and a control group without MACE.Furthermore,the MACE group was subdivided into lethal and non-lethal groups for prognostic analysis.Alongside hematological parameters,an additional 13 hematological-derived ratios(HDRs)were monitored,and their prognostic role was investigated.RESULTS Hematological parameters did not significantly differ between non-ST segment elevation myocardial infarction(NSTEMI)patients with MACE and a control group at T1 and T2.However,significant disparities emerged in HDRs among NSTEMI patients with lethal and non-lethal outcomes post-MACE.Notably,neutrophil-to-lymphocyte ratio(NLR)and platelet-to-lymphocyte ratio(PLR)were elevated in lethal outcomes.Furthermore,C-reactive protein-to-lymphocyte ratio(CRP/Ly)at T1(>4.737)demonstrated predictive value[odds ratio(OR):3.690,P=0.024].Both NLR at T1(>4.076)and T2(>4.667)emerged as significant predictors,with NLR at T2 exhibiting the highest diagnostic performance,as indicated by an area under the curve of 0.811(95%CI:0.727-0.859)and OR of 4.915(95%CI:1.917-12.602,P=0.001),emphasizing its important role as a prognostic marker.CONCLUSION This study highlights the significant prognostic value of hemogram-derived indexes in predicting MACE among NSTEMI patients.During follow-up,NLR,PLR,and CRP/Ly offer important insights into the inflammatory processes underlying cardiovascular events.
文摘Publisher Correction to:Journal of Forestry Research(2025)36:29 https://doi.org/10.1007/s11676-025-01823-0 In Fig.4c of this article,the lower part of the figure was unintentionally cropped and incomplete during the publisher's production process.The published incorrect version and the corrected version of Fig.4 are given below.
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 Patients with type 2 diabetes mellitus(T2DM)face a heightened risk of future cardiovascular events.It is therefore important to stratify these patients according to their future cardiovascular event risk to allow early intervention and improve prognosis.Recent proposals have indicated that nontraditional lipoprotein ratios may be superior predictors of cardiovascular events compared to traditional lipid parameters.However,further evidence is required for widespread clinical ap-plication.AIM To elucidate the associations of nontraditional lipoprotein ratios with future cardiovascular events in patients with T2DM.METHODS This study performed post-hoc analysis of data obtained during a clinical trial involving 10182 participants.To ascertain the correlations between nontraditional lipoprotein ratios and future cardiovascular events,including major adverse cardiovascular events(MACEs)and congestive heart failure(CHF).We employed univariable and multivariable-adjusted Cox proportional hazards regression models.Potential dose-response relationships and threshold values were explored by conducting restricted cubic spline analyses and two-piecewise linear regression models.Possible relevant interactions influencing independent relationships were tested using subgroup and interaction analyses.RESULTS After adjustment for confounding factors,all nontraditional lipoprotein ratios studied were strongly associated with MACE risk in patients with T2DM.In comparison with patients in the lowest quartile,the hazard ratios(95%confidence intervals)of those in the highest quartile were 1.50(1.29-1.73),1.51(1.30-1.74),1.50(1.29-1.73),and 1.30(1.12-1.50)for total cholesterol/high-density lipoprotein cholesterol(HDL-C),low-density lipoprotein cholesterol/HDL-C,non-HDL-C/HDL-C,and remnant cholesterol/HDL-C,respectively.Similar findings were noted for CHF.Dose-response relationships between nontraditional lipoprotein ratios and MACE were observed,with threshold values of 7.29,6.29,and 2.15 for total cholesterol/HDL-C,non-HDL-C/HDL-C,and remnant cholesterol/HDL-C,respectively.However,no notable dose-response relationships were detected between nontraditional lipoprotein ratios and CHF.CONCLUSION Elevated nontraditional lipoprotein ratios may independently predict the risk of MACE and CHF in patients with T2DM.
基金Project(24A0006)supported by the Key Project of Scientific Research Fund of Hunan Provincial Department of Education,ChinaProject(2024JJ5430)supported by the Natural Science Foundation of Hunan Province,ChinaProjects(2024JK2045,2023RC3061)supported by the Science and Technology Innovation Program of Hunan Province,China。
文摘A high-speed train travelling from the open air into a narrow tunnel will cause the“sonic boom”at tunnel exit.When the maglev train’s speed reaches 600 km/h,the train-tunnel aerodynamic effect is intensified,so a new mitigation method is urgently expected to be explored.This study proposed a novel asymptotic linear method(ALM)for micro pressure wave(MPW)mitigation to achieve a constant gradient of initial c ompression waves(ICWs),via a study with various open ratios on hoods.The properties of ICWs and MPWs under various open ratios of hoods were analyzed.The results show that as the open ratio increases,the MPW amplitude at the tunnel exit initially decreases before rising.At the open ratio of 2.28%,the slope of the ICW curve is linearly coincident with a supposed straight line in the ALM,which further reduces the MPW amplitude by 26.9%at 20 m and 20.0%at 50 m from the exit,as compared to the unvented hood.Therefore,the proposed method effectively mitigates MPW and quickly determines the upper limit of alleviation for the MPW amplitude at a fixed train-tunnel operation condition.All achievements provide a ne w potential measure for the adaptive design of tunnel hoods.
文摘BACKGROUND An efficient index holds the potential to predict rectal cancer prognosis.AIM To investigate the impact of neutrophil-to-lymphocyte ratio(NLR),platelet-tolymphocyte ratio(PLR),and monocyte-to-lymphocyte ratio(MLR)on rectal cancer prognosis.METHODS This retrospective study involved 180 patients with rectal cancer from the Changzhi People’s Hospital of Shanxi Province.A 2-mL blood sample was collected at 24 h preoperatively and 72 h postoperatively to measure neutrophils,lymphocytes,platelets,and monocytes using an automatic blood analyzer.Preoperative and postoperative NLR,PLR,and MLR were compared.Patients were followed up for 12 months and categorized into good and poor prognosis groups.A receiver operating characteristic curve was constructed to analyze their predictive values.RESULTS The NLR,PLR,and MLR values were significantly lower post-surgery(P<0.05).A total of 152 and 28 patients were categorized in the good and poor prognosis groups,respectively.Patients with poor prognoses exhibited slightly higher postoperative NLR,PLR,and MLR values than those with good prognoses(P<0.05).Receiver operating characteristic analysis showed that the area under the curve for NLR,PLR,and MLR was 0.828 with a sensitivity and specificity of 89.29%and 90.79%,respectively.These values were higher than individual NLR(area under the curve:0.660,sensitivity:67.86%,specificity:54.61%),PLR(0.668,75.00%,55.30%),and MLR(0.635,60.71%,48.03%),all showing statistically significant differences(P<0.05),effectively predicting patient outcomes.CONCLUSION The findings of this study indicated that NLR,PLR,and MLR values of patients with rectal cancer can be used to effectively predict the outcome of patients.
文摘Driver distraction is a leading cause of traffic accidents,with fatigue being a significant contributor.This paper introduces a novel method for detecting driver distraction by analyzing facial features using machine deep learning and 68 face model.The proposed system assesses driver tiredness by measuring the distance between key facial landmarks,such as the distance between the eyes and the angle of the mouth,to evaluate signs of drowsiness or disengagement.Real-time video feed analysis allows for continuous monitoring of the driver’s face,enabling the system to detect behavioral cues associated with distraction,such as eye closures or changes in facial expressions.The effectiveness of this method is demonstrated through a series of experiments on a dataset of driver videos,which proves that the approach can accurately assess tiredness and distraction levels under various driving conditions.By focusing on facial landmarks,the system is computationally efficient and capable of operating in real-time,making it a practical solution for in-vehicle safety systems.This paper discusses the system’s performance,limitations,and potential for future enhancements,including integration with other in-vehicle technologies to provide comprehensive driver monitoring.
文摘Much of the research has focused on identifying bridge frequencies for health monitoring,while the bridge damping ratio also serves as an important factor in damage detection.This study presents an enhanced method for identifying bridge damping ratios using a two-axle,three-mass test vehicle,relying on wheel responses captured by only two mounted sensors.Damping ratio estimation formulas are derived using both the Hilbert Transform(HT)and Wavelet Transform(WT),with a consistent formulation that confirms accurate estimation is achievable with minimal instrumentation,particularly when addressing the support effect.A comparative analysis of the two signal processing techniques reveals the superior performance of WT in identifying bridge damping ratios.The effectiveness of the proposed procedure and formulas is validated through a detailed parametric study,demonstrating robustness across bridges with varying modal damping ratios and different spans using minimal sensors.Moreover,the present study shows that responses from only the first two spans of a multi-span bridge are sufficient for reliable damping estimation,underscoring the practicality and scalability of the procedure for structural health monitoring applications.
基金Project(52374153)supported by the National Natural Science Foundation of ChinaProject(kq2502150)supported by the Natural Science Foundation of Changsha,China。
文摘Cemented tailings backfill(CTB)is a crucial support material for ensuring the long-term stability of underground goafs.A comprehensive understanding of its compressive mechanical behavior is essential for improving engineering safety.Although extensive studies have been conducted on the uniaxial compressive properties of CTB,damage constitutive models that effectively capture its damage evolution process remain underdeveloped,and its failure mechanisms are not yet fully clarified.To address these gaps,this study conducted systematic uniaxial compression tests on CTB specimens prepared with varying cement-tailings ratios.The results revealed distinct compaction and softening phases in the stress−strain curves.A lower cement-tailings ratio significantly reduced the strength and deformation resistance of CTB,along with a decrease in elastic energy accumulation at peak stress and dissipation energy in the post peak stage.Based on these findings,a modified damage constitutive model was developed by introducing a correction factor,enabling accurate simulation of the entire uniaxial compression process of CTB with different cement-tailings ratios.Comparative analysis with classical constitutive models validated the proposed model’s accuracy and applicability in describing the compressive behavior of CTB.Furthermore,particle size distribution and acoustic emission tests were employed to investigate the influence of cement-tailings ratio on failure mechanisms.The results indicated that a lower cement-tailings ratio leads to coarser particle sizes,which intensify shear-related acoustic emission signals and ultimately result in more pronounced macroscopic shear failure.This study provides theoretical support and practical guidance for the optimal design of CTB mix ratios.
文摘Flow characteristics around a wall-mounted square cylinder have been numerically simulated at aspect ratios (AR) ranging from 4 to 7 at Re =10 000. Four turbulence models have been compared in terms of drag coefficient (C_D). The closest result has been provided by two turbulence models, namely, k-ε Realizable and k ?ω Shear Stress Transport (SST). Hence, these models were utilized to present the flow patterns of pressure distributions, turbulent kinetic energy values, velocity magnitude values with streamlines, streamwise velocity components, crossstream velocity components and spanwise velocity components on different planes. Flow stagnation has been attained in front of the cylinder. Pressure values peaked for the upstream region. Over the cylinders, the tip vortex structure was dominant owing to the influence of the free end. Flow separation from the top front edge of the body has been obtained. The dividing streamline affected by the flow separation was highly effective in the wake region and moved nearer to the body when the aspect ratio was decreased;the reason was the wake shrinkage owing to the decreasing aspect ratio. Upwash and downwash have been seen in the cylinder wake. These two models presented similar flow patterns and drag coefficients. These drag coefficients are in good agreement with those in previous studies.
基金supported by the National Natural Science Foundation of China(NSFC)under Grant Nos.52288102,52322101,92163215,52174364,52101143,U23A20542the Fundamental Research Funds for the Central Universities under Grant No.30922010202+1 种基金the 100 Talents Plan of Hebei Province under Grant No.E2020100005the Natural Science Foundation of Hebei Province under Grant No.E2022203109.
文摘Polysynthetic twinned(PST)TiAl single crystal specifically refers to a fully lamellar TiAl single crystal with parallel phase interfaces and twin interfaces grown by directional solidification.In this paper,PST single crystals with different phase ratios are obtained by annealing at specific temperatures and holding times.The results show that the diffusion rates of Ti and Al elements at various temperatures directly trigger and propel the surface recrystallization and variation in the internal phase ratio.When the temperature is lower than 1448 K,the diffusion rate of Ti is obviously higher than that of Al,which causes one denseα_(2)recrystallized layer to form on the surface of TiAl single crystals.Meanwhile,as more Ti elements migrate to the surface,theα_(2)phase ratio inside the TiAl single crystal thereby decreases.When the temperature exceeds 1448 K,the diffusion rate of Al gradually reverses to exceed that of Ti,which forms the surface sandwiched recrystallization dominated byγphase and simultaneously increasesα_(2)phase ratio inside the TiAl single crystal.The variation in the two-phase ratio directly induces a significant change in the lamellae thickness,which exhibits different tensile behaviors of PST-TiAl single crystal.When theα_(2)phase content is less than 20%,widerγlamellae make it easier for dislocations to be activated within its lamellae and continuously move across theγ/α_(2)interfaces,thereby obtaining better tensile plasticity.As theα_(2)phase content exceeds 30%,finerγlamellae inhibit the dislocation initiation,resulting in the fracture occurrence of TiAl single crystal before yielding.No matter how the phase ratio changes,the crack preferentially initiates withinα_(2)lamellae.However,the crack propagation follows different paths based on variousγlamella thicknesses.The fracture mode of PST-TiAl single crystal also changes from shear fracture along slip bands within theγlamella to brittle fracture along the{1¯100}planes withinα_(2)lamella.
基金supported by the National Natural Science Foundation of China(Nos.52270106 and 22266021)Yunnan Major Scientific and Technological Projects(No.202202AG050005)Yunnan Fundamental Research Projects(No.202201AT070116).
文摘This study employed a wet impregnation method to synthesize five types of Cu/HZSM-5 adsorbents with Si/Al ratios of 25,50,85,200,and 300,used for the removal of H_(2)S in lowtemperature,low-oxygen environments.The impact of different Si/Al ratios on the adsorption oxidative performance of Cu_(30)/HZSM-5–85 adsorbents was investigated.According to the performance test results,Cu_(30)/HZSM-5–85 exhibited the highest breakthrough capacity,reaching 231.75 mg H_(2)S/g_(sorbent).Cu/HZSM-5 sorbent maintains a strong ability to remove H_(2)S even under humid conditions and shows excellent water resistance.XRD,BET,and XPS results revealed that CuO is the primary active species,with Cu_(30)/HZSM-5–85 having the largest surface area and highest CuO content,providing more active sites for H_(2)S adsorption.H_(2)-TPR and O_(2)-TPD results confirmed that Cu_(30)/HZSM-5–85 sorbent exhibits outstanding redox properties and oxygen storage capacity,contributing to excellent oxygen transferability in the molecular sieve adsorption-oxidation process.With notable characteristics such as a large surface area,high desulfurization efficiency,and water resistance,Cu_(30)/HZSM-5–85 sorbents hold significant importance for industrial applications.
文摘Background:Diabetes mellitus(DM)is a prevalent chronic metabolic condition characterized by high blood sugar levels,resulting from insufficient insulin production or ineffective insulin use,posing substantial global health issues.Research on the relationship between glycemic status and the ratio of neutrophils to lymphocytes(NLR)and monocytes to lymphocytes(MLR)is limited.This study aimed to fill these knowledge gaps by examining the connection between DM and inflammatory markers within the Asir region.Methods:Data from 3545 participants were retrospectively analyzed.The dataset,gathered between 2021 and 2023,comprises 38 laboratory tests obtained from the Future Lab Pioneer database.The study's inclusion criteria focused on diabetes profile tests(glycated hemoglobin[HbA1c]and fasting blood glucose[FBG])and manually computed inflammatory markers(NLR and MLR),which were stratified by age and sex.Results:This study demonstrated significant differences in NLR levels compared with FBG levels across all adult age groups and adult female participants(p<0.0001),as well as among all elderly age groups(p=0.0006)and elderly women(p=0.01).MLR levels were significant in all adult age groups(p=0.04)and in adult women(p=0.02).When NLR and MLR were compared to HbA1c levels,a significant difference in the mean NLR was found in adult women(p=0.005).Additionally,the mean MLR levels were significant in all adult age groups(p=0.04)and adult women(p=0.02).Conclusion:Although a larger sample size is necessary for this research,the results indicate that NLR and MLR could serve as valuable indicators for evaluating inflammation in people with disrupted glucose metabolism,particularly in adult and female populations.
基金Supported by Excellent Youth Science Fund Project(Overseas)of Shandong Province,China(No.2023HWYQ-029)China Postdoctoral Science Foundation(No.2023MD744219)+3 种基金Zhejiang Province Selected Funding for Postdoctoral Research Projects,China(No.ZJ2023040)Youth Project of Natural Science Foundation of Shandong Province,China(No.ZR2023QE127)China National University Student Innovation and Entrepreneurship Development Program(No.202310422009)Major Basic Research Program of the Natural Science Foundation of Shandong Province,China(No.ZR2019ZD08).This research was in part carried out at the Center for Functional Nanomaterials(CFN),Brookhaven National Laboratory(BNL),which is supported by the U.S.Department of Energy,Office of Basic Energy Sciences,under Contract No.DE-SC0012704.
文摘Solar sailing is a promising propellant-free approach to propelling spacecraft in space.However, the propelling efficiency of conventional solar sail spacecraft is limited by their areato-mass ratios. This paper proposes a novel design of micro solar sails with area-to-mass ratios above 100 m^(2)/kg for next-generation chip-scale spacecraft. Bilayer thin films developed by Microelectromechanical Systems(MEMS) technologies were patterned into grid microstructures, and theoretical analysis of a sail prototype was conducted. The electro-thermal and thermo-mechanical models of the solar sail in geospace were established by taking effects of Joule heating, solar radiation, and thermal re-emission into consideration, enabling rapid prediction of its threedimensional(3-D) reconfiguration from the as-released two-dimensional(2-D) microstructure.Adjustment of the Chip Sail's acceleration arising from the sail's morphing was also analytically modeled. Fabrication and characterization of the sail prototype made of multiple Al/Ni_(50)Ti_(50) bilayer beams were accomplished. In-situ SEM imaging of the sail prototype in vacuum chamber witnessed an active and continuous 3-D reconfiguration under Joule heating, and over 90° deformation was detected by applying a DC voltage of 0.078 V. Theoretical and experimental work on the solar sail with at least 10 times higher area-to-mass ratios than conventional ones will lay a solid foundation for efficient solar sailing.
基金supported by National Natural Science Foundation of China(No.11405025).
文摘The yield ratios of neutron-proton(R(n/p))and^(3)H-^(3)He(R(^(3)H∕^(3)He))with reduced rapidity from 0 to 0.5 were simulated at 50 MeV/u even-even ^(36−56)Ca+^(40)Ca,even-even ^(48−78)Ni+^(58)Ni,and ^(100−139)Sn(every third isotopes)+112 Sn for full reduced impact parameters using the isospin-dependent quantum molecular dynamics(IQMD)model.The neutron and proton density distributions and root-mean-square radii of the reaction systems were obtained using the Skyrme-Hartree-Fock model,which was used for the phase space initialization of the projectile and target in IQMD.We defined the unified neutron skin thickness asΔRnp=<r^(2)>^(1∕2) n−<r^(2)>^(1∕2)p,which was negative for neutron-deficient nuclei.The unifiedΔRnp values for nuclei with the same relative neutron excess from different isotopic chains were nearly equal,except for extreme neutron-rich isotopes,which is a type of scaling behavior.The yield ratios of the three isotopic chain-induced reactions,which depended on the reduced impact parameter and unified neutron skin thickness,were studied.The results showed that both R(n/p)and R(^(3)H∕^(3)He)decreased with a reduced impact parameter for extreme neutron-deficient isotopes;however,they increased with reduced impact parameters for extreme neutron-rich isotopes,and increased with theΔRnp of the projectiles for all reduced impact parameters.In addition,a scaling phenomenon was observed betweenΔR np and the yield ratios in peripheral colli-sions from different isotopic chain projectiles(except for extreme neutron-rich isotopes).Thus,R(n/p)and R(^(3)H∕^(3)He)from peripheral collisions were suggested as experimental probes for extracting the neutron or proton skin thicknesses of non-extreme neutron-rich nuclei from different isotopic chains.
文摘This study is a contribution to improving rice productivity on acidic plateau soils of the tropical rainforest zone. It is based on taking into account the cationic balances of the soil in order to optimize the phosphorus (P) nutrition of rice on these acidic soils, where this nutrient constitutes a limiting factor for agricultural production. Three (3) pot trials were conducted in Adiopodoumé in the forested south of Côte d’Ivoire. The interactive effects of calcium carbonate (0, 25, 50 and 75 kg Ca ha<sup>−1</sup>) and magnesium sulfate (0, 25, 50 and 75 kg Mg ha<sup>−1</sup>) were evaluated on the response of NERICA 5 rice at doses 0, 25, 50 and 75 kg P ha<sup>−1</sup> of natural phosphate from Togo, applied only once at the start of the experiment. Additional fertilizers of nitrogen (N) (100 kg N ha<sup>−1</sup>) and potassium (K) (50 kg KCl ha<sup>−1</sup>) were added to each of the tests in a split-plot device. The test results revealed a paddy production potential of approximately 3 to 5 t⋅ha<sup>−1</sup> for NERICA 5 on an acidic soil, under the effect of the interaction of P, Ca and Mg. The quadratic response of rice yield to the doses of these fertilizers would be more dependent on their balance, itself influenced by Ca nutrition. For the sustainability and maintenance of rice production in agro-ecology studied, it was recommended doses of 38 kg Ca ha<sup>−1</sup>, 34 kg Mg ha<sup>−1</sup> in a Ca/Mg ratio (1/1) with intakes of 41 kg P ha<sup>−1</sup>, overall in a ratio 1/1/1 (P/Ca/Mg) more favorable to the availability of free iron considered a guiding element of mineral nutrition. Thus, these promising results should be confirmed in a real environment for better management of the fertilization of rice cultivated on acidic plateau soils in Côte d’Ivoire.
基金financially supported by the National Natural Science Foundation of China(Grant No.51890913)the Natural Science Foundation of Sichuan Province of China(Grant No.2023YFQ0111)。
文摘In an effort to investigate and quantify the patterns of local scour,researchers embarked on an in-depth study using a systematic experimental approach.The research focused on the effects of local scour around a set of four piles,each subjected to different hydromechanical conditions.In particular,this study aimed to determine how different attack angles—the angles at which the water flow impinges on the piles,and gap ratios—the ratios of the spacing between the piles to their diameters,influence the extent and nature of scour.A comprehensive series of 35 carefully designed experiments were orchestrated,each designed to dissect the nuances in how the gap ratio and attack angle might contribute to changes in the local scour observed at the base of pile groups.During these experimental trials,a wealth of local scour data were collected to support the analysis.These data included precise topographic profiles of the sediment bed around the pile groups,as well as detailed scour time histories showing the evolution of scour at strategic feature points throughout the test procedure.The analysis of the experimental data provided interesting insights.The study revealed that the interplay between the gap ratio and the attack angle had a pronounced influence on the scouring dynamics of the pile groups.One of the key observations was that the initial phases of scour,particularly within the first hour of water flow exposure,were characterized by a sharp increase in the scour depth occurring immediately in front of the piles.After this initial rapid development,the scour depth transitioned to a more gradual change rate.In contrast,the scour topography around the piles continuously evolved.This suggests that sediment displacement and the associated sculpting of the seabed around pile foundations are sustained and progressive processes,altering the underwater landscape over time.The results of this empirical investigation have significant implications for the design and construction of offshore multi-pile foundations,providing a critical reference for engineers and designers to estimate the expected scour depth around such structures,which is an integral part of decisions regarding foundation design,selection of structural materials,and implementation of scour protection measures.
文摘This study conducts both numerical and empirical assessments of thermal transfer and fluid flow characteristics in a Solar Air Collector(SAC)using a Delta Wing Vortex Generator(DWVG),and the effects of different height ratios(Rh=0.6,0.8,1,1.2 and 1.4)in delta wing vortex generators,which were not considered in the earlier studies,are investigated.Energy and exergy analyses are performed to gain maximum efficiency.The Reynolds number based on the outlet velocity and hydraulic diameter falls between 4400 and 22000,corresponding to the volume flow rate of 5.21–26.07 m^(3)/h.It is observed that the delta wing vortex generators with a higher height ratio yield maximum heat transfer enhancement and overall enhancement ratio.The empirical and numerical findings demonstrate that the exergy and thermal efficiencies decline in a specific range.TheNusselt number,pressure drop,energy,and exergy efficiencies enhance with rising Reynolds number,although the friction coefficient diminishes.The maximum heat transfer enhancement is 57%.According to the evaluation of exergy efficiency,the greatest efficiency of 31.2%is obtained at Rh=1.4 and Reynolds number 22000.
文摘Background: The signal-to-noise ratio (SNR) is recognized as an index of measurements reproducibility. We derive the maximum likelihood estimators of SNR and discuss confidence interval construction on the difference between two correlated SNRs when the readings are from bivariate normal and bivariate lognormal distribution. We use the Pearsons system of curves to approximate the difference between the two estimates and use the bootstrap methods to validate the approximate distributions of the statistic of interest. Methods: The paper uses the delta method to find the first four central moments, and hence the skewness and kurtosis which are important in the determination of the parameters of the Pearsons distribution. Results: The approach is illustrated in two examples;one from veterinary microbiology and food safety data and the other on data from clinical medicine. We derived the four central moments of the target statistics, together with the bootstrap method to evaluate the parameters of Pearsons distribution. The fitted Pearsons curves of Types I and II were recommended based on the available data. The R-codes are also provided to be readily used by the readers.
文摘Technologies for reducing corn leaf burn caused by foliar spray of urea-ammonium nitrate (UAN) during the early growing season are limited. A field experiment was carried out to evaluate the effects of humic acid on corn leaf burn caused by foliar spray of undiluted UAN solution on corn canopy at Jackson, TN in 2018. Thirteen treatments of the mixtures of UAN and humic acid were evaluated at V6 of corn with different UAN application rates and different UAN/humic acid ratios. Leaf burn during 1 2, 3, 4, 5, 6, 7, and 14 days after UAN foliar spray significantly differed between with or without humic acid addition. The addition of humic acid to UAN significantly reduced leaf burn at each UAN application rate (15, 25, and 35 gal/acre). The reduction of leaf burn was enhanced as the humic acid/UAN ratio went up from 10% to 30%. Leaf burn due to foliar application of UAN became severer with higher UAN rates. The linear regression of leaf burn 14 days after application with humic acid/UAN ratio was highly significant and negative. However, the linear regression of leaf burn 14 days after application with the UAN application rate was highly significant and positive. In conclusion, adding humic acid to foliar-applied UAN is beneficial for reducing corn leaf burn during the early growing season.