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Ecological risk assessment and early warning of heavy metal cumulation in the soils near the Luanchuan molybdenum polymetallic mine concentration area,Henan Province,central China 被引量:13
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作者 Zhen-yu Chen Yuan-yi Zhao +3 位作者 Dan-li Chen Hai-tao Huang Yu Zhao Yu-jing Wu 《China Geology》 CAS CSCD 2023年第1期15-26,共12页
The Luanchuan molybdenum polymetallic mine concentration area is rich in mineral resources and has a long history of mining.The environmental impact of long-term mining activities cannot be ignored.It is of great sign... The Luanchuan molybdenum polymetallic mine concentration area is rich in mineral resources and has a long history of mining.The environmental impact of long-term mining activities cannot be ignored.It is of great significance to study the ecological risk and the accumulation trends of heavy metals in the soil of mining areas for scientific prevention and control of heavy metal pollution.Taking the Taowanbeigou River Basin in the mine concentration area as the research object,the ecological pollution risk and cumulative effect of heavy metals in the soil of the basin were studied by using the comprehensive pollution index method,potential ecological risk assessment method and geoaccumulation index method.On this basis,the cumulative exceeding years of specific heavy metals were predicted by using the early warning model.The comprehensive potential ecological risk of heavy metals in the soil near the Luanchuan mine concentration area is moderate,and the single element Cd is the main ecological risk factor,with a contribution rate of 53.6%.The overall cumulative degrees of Cu and Pb in the soil are“none-moderate”,Zn and Cd are moderate,Mo has reached an extremely strong cumulative level,Hg,As and Cr risks are not obvious,and the overall cumulative risks order is Mo>Cd>Zn>Cu>Pb>Hg.According to the current accumulation rate and taking the risk screening values for soil contamination of agricultural land as the reference standard,the locations over standard rates of Cu,Zn and Cd will exceed 78%in 90years,and the over standard rate of Pb will reach approximately 57%in 200 years.The cumulative exceeding standard periods of As,Cr and Hg are generally long,which basically indicates that these elements do not pose a significant potential threat to the ecological environment.Mining activities will accelerate the accumulation of heavy metals in soil.With the continuous development of mining activities,the potential pollution risk of heavy metals in the soil of mining areas will also increase. 展开更多
关键词 Soil Heavy metals Mining impact Cumulative effect Potential ecological risk cumulation early warning Luanchuan mine concentration area Environmental geological survey engineering
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Cumulation of a spherically converging shock wave in metals and its dependence on elastic-plastic properties, phase transitions, spall and shear fractures
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作者 Evgeny A.Kozlov Alexsander V.Petrovtsev 《International Journal of Modeling, Simulation, and Scientific Computing》 EI 2015年第1期26-38,共13页
Consideration is given to results of experimental and theoretical investigations how alpha-epsilon phase transition in the unalloyed iron and the 30 KhGSA steel and its absence in the austenitic 12Kh18N10T stainless s... Consideration is given to results of experimental and theoretical investigations how alpha-epsilon phase transition in the unalloyed iron and the 30 KhGSA steel and its absence in the austenitic 12Kh18N10T stainless steel influence processes under explosive deformation of spheres made of these materials.Polymorphous transition is shown to significantly effect on:amount of explosion-products energy transferred to a sphere,evolution of the converging-wave structure and its parameters,profiles of stress wave and temperature T(R,t)for some Lagrangian particles along the sphere radius,character of energy cumulation under spherical convergence of waves. 展开更多
关键词 cumulation spherically converging shock wave elastic-plastic properties phase transitions spall and shear fractures
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Aluminium Uptake and Accumulation in the Hyperaccumulator Camellia Oleifera Abel 被引量:14
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作者 ZENG Qi-Long CHEN Rong-Fu +2 位作者 ZHAO Xue-Qiang WANG Huo-Yan SHEN Ren-Fang 《Pedosphere》 SCIE CAS CSCD 2011年第3期358-364,共7页
Oiltea camellia (Camellia oleifera Abel.), an aluminium (Al) hyperaccumulator, grows well on acid soils in tropical or subtropical areas. In this study, the growth of oiltea camellia in response to Al application ... Oiltea camellia (Camellia oleifera Abel.), an aluminium (Al) hyperaccumulator, grows well on acid soils in tropical or subtropical areas. In this study, the growth of oiltea camellia in response to Al application and the characteristics of Al uptake and accumulation were investigated using laboratory and field experiments. The growth of oiltea camellia seedlings in the nutrient solution tended to be stimulated by addition of Al. Results of the field experiment showed that oiltea camellia accumulated 11 000 mg kg-1 Al in leaves within 10 months, and the average rate of Al accumulation in new leaves was about 1100 mg kg-1 month-1; however, the monthly rate varied and was highest in spring and autumn. The results of the laboratory experiment on Al uptake by oiltea camellia seedlings in CaC12 solutions with various forms of Al showed that large amounts of Al supplied as Al3+ and Al complexes Al-malate (1:1) and Al-F (1:1) were infiuxed into oiltea camellia roots, whereas Al supplied as Al-citrate (1:1), Al-F (1:6), Al-oxalate (1:3), and Al-oxalate (1:1) complexes exhibited low affinity to oiltea camellia roots. The kinetics of Al3+ cumulative uptake in excised roots and intact plants showed a biphasic pattern, with an initial rapid phase followed by a slow phase. The Al cumulative uptake was unaffected by low temperature, which indicated that Al uptake in oiltea camellia was a passive process. The efficient influx of Al into the roots and the high transport rate in specific seasons were presumed to account for the plentiful Al accumulation in leaves of oiltea camellia. 展开更多
关键词 Al3+ Al complexes Al influx cumulative uptake oiltea camellia
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Cumulative effects of excess high-normal alanine aminotransferase levels in relation to new-onset metabolic dysfunction-associated fatty liver disease in China 被引量:7
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作者 Jing-Feng Chen Zhuo-Qing Wu +5 位作者 Hao-Shuang Liu Su Yan You-Xiang Wang Miao Xing Xiao-Qin Song Su-Ying Ding 《World Journal of Gastroenterology》 SCIE CAS 2024年第10期1346-1357,共12页
BACKGROUND Within the normal range,elevated alanine aminotransferase(ALT)levels are associated with an increased risk of metabolic dysfunction-associated fatty liver disease(MAFLD).AIM To investigate the associations ... BACKGROUND Within the normal range,elevated alanine aminotransferase(ALT)levels are associated with an increased risk of metabolic dysfunction-associated fatty liver disease(MAFLD).AIM To investigate the associations between repeated high-normal ALT measurements and the risk of new-onset MAFLD prospectively.METHODS A cohort of 3553 participants followed for four consecutive health examinations over 4 years was selected.The incidence rate,cumulative times,and equally and unequally weighted cumulative effects of excess high-normal ALT levels(ehALT)were measured.Cox proportional hazards regression was used to analyse the association between the cumulative effects of ehALT and the risk of new-onset MAFLD.RESULTS A total of 83.13%of participants with MAFLD had normal ALT levels.The incidence rate of MAFLD showed a linear increasing trend in the cumulative ehALT group.Compared with those in the low-normal ALT group,the multivariate adjusted hazard ratios of the equally and unequally weighted cumulative effects of ehALT were 1.651[95%confidence interval(CI):1.199-2.273]and 1.535(95%CI:1.119-2.106)in the third quartile and 1.616(95%CI:1.162-2.246)and 1.580(95%CI:1.155-2.162)in the fourth quartile,respectively.CONCLUSION Most participants with MAFLD had normal ALT levels.Long-term high-normal ALT levels were associated with a cumulative increased risk of new-onset MAFLD. 展开更多
关键词 Metabolic dysfunction-associated fatty liver disease High-normal alanine aminotransferase level Cumulative effect Cox proportional hazards regression Cohort study
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Mechanical responses of anchoring structure under triaxial cyclic loading 被引量:2
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作者 Peng Wang Nong Zhang +5 位作者 Qun Wei Xingliang Xu Guangzhen Cui Aoran Li Sen Yang Jiaguang Kan 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第2期545-560,共16页
Dynamic load on anchoring structures(AS)within deep roadways can result in cumulative damage and failure.This study develops an experimental device designed to test AS under triaxial loads.The device enables the inves... Dynamic load on anchoring structures(AS)within deep roadways can result in cumulative damage and failure.This study develops an experimental device designed to test AS under triaxial loads.The device enables the investigation of the mechanical response,failure mode,instability assessment criteria,and anchorage effect of AS subjected to combined cyclic dynamic-static triaxial stress paths.The results show that the peak bearing strength is positively correlated with the anchoring matrix strength,anchorage length,and edgewise compressive strength.The bearing capacity decreases significantly when the anchorage direction is severely inclined.The free face failure modes are typically transverse cracking,concave fracturing,V-shaped slipping and detachment,and spallation detachment.Besides,when the anchoring matrix strength and the anchorage length decrease while the edgewise compressive strength,loading rate,and anchorage inclination angle increase,the failure intensity rises.Instability is determined by a negative tangent modulus of the displacement-strength curve or the continued deformation increase against the general downward trend.Under cyclic loads,the driving force that breaks the rock mass along the normal vector and the rigidity of the AS are the two factors that determine roadway stability.Finally,a control measure for surrounding rock stability is proposed to reduce the internal driving force via a pressure relief method and improve the rigidity of the AS by full-length anchorage and grouting modification. 展开更多
关键词 Triaxial stress Dynamic-static combination load Cyclic loading Anchoring structure(AS) Cumulative damage
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Spatiotemporal changes of gross primary productivity and its response to drought in the Mongolian Plateau under climate change 被引量:1
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作者 ZHAO Xuqin LUO Min +3 位作者 MENG Fanhao SA Chula BAO Shanhu BAO Yuhai 《Journal of Arid Land》 SCIE CSCD 2024年第1期46-70,共25页
Gross primary productivity(GPP)of vegetation is an important constituent of the terrestrial carbon sinks and is significantly influenced by drought.Understanding the impact of droughts on different types of vegetation... Gross primary productivity(GPP)of vegetation is an important constituent of the terrestrial carbon sinks and is significantly influenced by drought.Understanding the impact of droughts on different types of vegetation GPP provides insight into the spatiotemporal variation of terrestrial carbon sinks,aiding efforts to mitigate the detrimental effects of climate change.In this study,we utilized the precipitation and temperature data from the Climatic Research Unit,the standardized precipitation evapotranspiration index(SPEI),the standardized precipitation index(SPI),and the simulated vegetation GPP using the eddy covariance-light use efficiency(EC-LUE)model to analyze the spatiotemporal change of GPP and its response to different drought indices in the Mongolian Plateau during 1982-2018.The main findings indicated that vegetation GPP decreased in 50.53% of the plateau,mainly in its northern and northeastern parts,while it increased in the remaining 49.47%area.Specifically,meadow steppe(78.92%)and deciduous forest(79.46%)witnessed a significant decrease in vegetation GPP,while alpine steppe(75.08%),cropland(76.27%),and sandy vegetation(87.88%)recovered well.Warming aridification areas accounted for 71.39% of the affected areas,while 28.53% of the areas underwent severe aridification,mainly located in the south and central regions.Notably,the warming aridification areas of desert steppe(92.68%)and sandy vegetation(90.24%)were significant.Climate warming was found to amplify the sensitivity of coniferous forest,deciduous forest,meadow steppe,and alpine steppe GPP to drought.Additionally,the drought sensitivity of vegetation GPP in the Mongolian Plateau gradually decreased as altitude increased.The cumulative effect of drought on vegetation GPP persisted for 3.00-8.00 months.The findings of this study will improve the understanding of how drought influences vegetation in arid and semi-arid areas. 展开更多
关键词 gross primary productivity(GPP) climate change warming aridification areas drought sensitivity cumulative effect duration(CED) Mongolian Plateau
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The lithology and composition of lunar mantle modified by ilmenite bearing cumulate:A thermodynamic model
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作者 Wei Huang Wei Du 《Acta Geochimica》 EI CAS CSCD 2024年第5期856-875,共20页
Due to their high density,the ilmenite-bearing cumulates(IBC)(with or without KREEP)formed during the late-stage lunar magma ocean solidification are thought to sink into the underlying lunar mantle and trigger lunar ... Due to their high density,the ilmenite-bearing cumulates(IBC)(with or without KREEP)formed during the late-stage lunar magma ocean solidification are thought to sink into the underlying lunar mantle and trigger lunar mantle overturn.Geophysical evidence implied that IBC may descend deep inside the Moon and remain as a partially molten layer at the core-mantle boundary(CMB).However,partial melting may have occurred on the mixed mantle cumulates during the sinking of IBC/KREEP and the silicate melt may be positively buoyant,thus preventing the IBC/KREEP layer from sinking to the CMB.Here,we perform thermodynamic simulation on the stability of lunar mantle cumulates at different depths mixed with different amounts of IBC/KREEP from an updated LMO model.The modeling results suggest that the sinking of IBC/KREEP will cause at least 5 wt%partial melting in the shallow(~120 km)and a much larger degree of partial melting in the deep lunar mantle(~420 km).Due to the density contrast with the surrounding mantle,IBC/KREEP-bearing melts could potentially decouple under certain conditions.The modified lunar mantle by sinking of IBC/KREEP can better explain the formation of different kinds of lunar basaltic magma than the primary lunar mantle formed through differentiation of lunar magma ocean.Sinking of IBC/KREEP back into the lunar mantle may introduce plagioclase,clinopyroxene,garnet,and incompatible radioactive elements into the deep lunar mantle,which will further affect the thermal and chemical evolution of the lunar interior. 展开更多
关键词 Ilmenite-bearing cumulate KREEP Partial melting Lunar mantle overturn pMELTS
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Non-Gaussianity detection of single-mode rotationally symmetric quantum states via cumulant method
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作者 向少华 黄利军 米贤武 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期264-273,共10页
The non-Gaussianity of quantum states incarnates an important resource for improving the performance of continuous-variable quantum information protocols.We propose a novel criterion of non-Gaussianity for single-mode... The non-Gaussianity of quantum states incarnates an important resource for improving the performance of continuous-variable quantum information protocols.We propose a novel criterion of non-Gaussianity for single-mode rotationally symmetric quantum states via the squared Frobenius norm of higher-order cumulant matrix for the quadrature distribution function.As an application,we study the non-Gaussianities of three classes of single-mode symmetric non-Gaussian states:a mixture of vacuum and Fock states,single-photon added thermal states,and even/odd Schr¨odinger cat states.It is shown that such a criterion is faithful and effective for revealing non-Gaussianity.We further extend this criterion to two cases of symmetric multi-mode non-Gaussian states and non-symmetric single-mode non-Gaussian states. 展开更多
关键词 non-Gaussianity criterion cumulant matrix quadrature distribution
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Study on cumulative effects of biological craniocerebral trauma under repeated blast
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作者 Xingyuan Huang Bingchen Xia +3 位作者 Lijun Chang Zhikang Liao Hui Zhao Zhihua Cai 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2024年第3期174-183,共10页
Repeated blast impacts on personnel in explosive environments can exacerbate craniocerebral trauma.Most existing studies focus on the injury effects of a single blast,lacking in-depth analysis on the injury effects an... Repeated blast impacts on personnel in explosive environments can exacerbate craniocerebral trauma.Most existing studies focus on the injury effects of a single blast,lacking in-depth analysis on the injury effects and cumulative effects of repeated blasts.Therefore,rats were used as the experimental samples to suffer from explosion blasts with different peak air overpressures(167 kPa~482 kPa)and varying number of repeated blasts.The cumulative effect of craniocerebral trauma was most pronounced for moderate repeated blast,showing approximately 95%increase of trauma severity with penta blast,and an approximately 85%increase of trauma severity with penta minor blast.The cumulative effect of craniocerebral trauma from severe,repeated blast has a smaller rate of change compared to the other two conditions.The severity of trauma from penta blast increased by approximately 69%compared to a single blast.Comprehensive physiological,pathological and biochemical analysis show that the degree of neurological trauma caused by repeated blasts is higher than that of single blasts,and the pathological trauma to brain tissue is more extensive and severe.The trauma degree remains unchanged after double blast,increases by one grade after triple or quadruple blast,and increases by two grades after penta blast. 展开更多
关键词 Repeated blast Craniocerebral trauma Trauma severity grade Cumulative effects
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Wigner function of optical cumulant operator and its dissipation in thermo-entangled state representation
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作者 张科 李兰兰 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期205-210,共6页
To conveniently calculate the Wigner function of the optical cumulant operator and its dissipation evolution in a thermal environment, in this paper, the thermo-entangled state representation is introduced to derive t... To conveniently calculate the Wigner function of the optical cumulant operator and its dissipation evolution in a thermal environment, in this paper, the thermo-entangled state representation is introduced to derive the general evolution formula of the Wigner function, and its relation to Weyl correspondence is also discussed. The method of integration within the ordered product of operators is essential to our discussion. 展开更多
关键词 Wigner function optical cumulant operator dissipation evolution thermo-entangled state representation integration within ordered product of operators
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Fatigue Crack Propagation Law of Corroded Steel Box Girders in Long Span Bridges
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作者 Ying Wang Longxiao Chao +1 位作者 Jun Chen Songbai Jiang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期201-227,共27页
In order to investigate the fatigue performance of orthotropic anisotropic steel bridge decks,this study realizes the simulation of the welding process through elastic-plastic finite element theory,thermal-structural ... In order to investigate the fatigue performance of orthotropic anisotropic steel bridge decks,this study realizes the simulation of the welding process through elastic-plastic finite element theory,thermal-structural sequential coupling,and the birth-death element method.The simulated welding residual stresses are introduced into the multiscale finite element model of the bridge as the initial stress.Furthermore,the study explores the impact of residual stress on crack propagation in the fatigue-vulnerable components of the corroded steel box girder.The results indicate that fatigue cracks at the weld toe of the top deck,the weld root of the top deck,and the opening of the transverse diaphragm will not propagate under the action of a standard vehicle load.However,the inclusion of residual stress leads to the propagation of these cracks.When considering residual stress,the fatigue crack propagation paths at the weld toe of the transverse diaphragm and the U-rib weld toe align with those observed in actual bridges.In the absence of residual stress,the cracks at the toe of the transverse diaphragm with a 15%mass loss rate are categorized as type I cracks.Conversely,when residual stress is considered,these cracks become I-II composite cracks.Residual stress significantly alters the cumulative energy release rate of the three fracturemodes.Therefore,incorporating the influence of residual stress is essential when assessing the fatigue performance of corroded steel box girders in long-span bridges. 展开更多
关键词 Residual stress crack propagation corroded steel box girder cumulative energy release rate
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Development of a novel critical nitrogen concentration-cumulative transpiration curve for optimizing nitrogen management under varying irrigation conditions in winter wheat
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作者 Tianyang Ye Yu Zhang +9 位作者 Jingyan Xuan Xintian Wang Yang Li Junhao Xu Liujun Xiao Leilei Liu Liang Tang Weixing Cao Bing Liu Yan Zhu 《The Crop Journal》 SCIE CSCD 2024年第4期1242-1251,共10页
Accurate nitrogen(N)nutrition diagnosis is essential for improving N use efficiency in crop production.The widely used critical N(Nc)dilution curve traditionally depends solely on agronomic variables,neglecting crop w... Accurate nitrogen(N)nutrition diagnosis is essential for improving N use efficiency in crop production.The widely used critical N(Nc)dilution curve traditionally depends solely on agronomic variables,neglecting crop water status.With three-year field experiments with winter wheat,encompassing two irrigation levels(rainfed and irrigation at jointing and anthesis)and three N levels(0,180,and 270 kg ha1),this study aims to establish a novel approach for determining the Nc dilution curve based on crop cumulative transpiration(T),providing a comprehensive analysis of the interaction between N and water availability.The Nc curves derived from both crop dry matter(DM)and T demonstrated N concentration dilution under different conditions with different parameters.The equation Nc=6.43T0.24 established a consistent relationship across varying irrigation regimes.Independent test results indicated that the nitrogen nutrition index(NNI),calculated from this curve,effectively identifies and quantifies the two sources of N deficiency:insufficient N supply in the soil and insufficient soil water concentration leading to decreased N availability for root absorption.Additionally,the NNI calculated from the Nc-DM and Nc-T curves exhibited a strong negative correlation with accumulated N deficit(Nand)and a positive correlation with relative grain yield(RGY).The NNI derived from the Nc-T curve outperformed the NNI derived from the Nc-DM curve concerning its relationship with Nand and RGY,as indicated by larger R2 values and smaller AIC.The novel Nc curve based on T serves as an effective diagnostic tool for assessing winter wheat N status,predicting grain yield,and optimizing N fertilizer management across varying irrigation conditions.These findings would provide new insights and methods to improve the simulations of water-N interaction relationship in crop growth models. 展开更多
关键词 Crop dry matter Crop cumulative transpiration Bayesian statistical model Critical nitrogen dilution curve Nitrogen nutrition index
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Postponing AMI to 100 Years: An Emerging Concept
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作者 Prabhash Chand Manoria 《World Journal of Cardiovascular Diseases》 CAS 2024年第6期401-408,共8页
Acute myocardial infarction is a deadly disease, and in the Indian context, it occurs at a younger age, even below the age of 40 years, and sometimes even below 30 years. These young MI patients have high mortality ra... Acute myocardial infarction is a deadly disease, and in the Indian context, it occurs at a younger age, even below the age of 40 years, and sometimes even below 30 years. These young MI patients have high mortality rates, and many of them are not able to reach the hospital. The pathophysiology of AMI is very well understood. AMI is a multifactorial disease and has several risk factors, like dyslipidemia, diabetes, hypertension, smoking, diet, etc. However, low-density lipoprotein cholesterol (LDL-C) has a very strong causal relationship with atherosclerosis. Reducing LDL-C to <70 results in the arrest of the progression of atherosclerosis, and slashing its level to below 50 produces the regression of atherosclerosis. The cumulative exposure of LDL-C to the arterial wall is a very strong determinant of atherosclerosis and the development of AMI. The coronary heart disease (CHD) threshold target of LDL-C for the development of AMI is roughly 7000 mg/year. If LDL-C is 100 mg/dL from an early age, the CHD threshold target for the development of AMI will reach 70 years of age. However, if LDL-C target is <70 mg/dL from an early age, the patients will reach the CHD threshold of LDL-C at the age of 100 years. Based on the current science, this is an emerging concept to postpone AMI by several years, even up to 100 years. The goal of LDL-C <70 mg/dL can be achieved by available oral or injectable drugs. Gene editing with CRISPR technology is emerging as a very exciting modality for lowering LDL-C to a very low level for the rest of life. 展开更多
关键词 Acute Myocardial Infarction Cumulative Exposure of LDL-C Inclisiran CRISPR Technology
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The Cumulative Method for Multiplication and Division
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作者 Muna Mohammed Hammuda 《Applied Mathematics》 2024年第5期349-354,共6页
This paper provides a method of the process of computation called the cumulative method, it is based upon repeated cumulative process. The cumulative method is being adapted to the purposes of computation, particularl... This paper provides a method of the process of computation called the cumulative method, it is based upon repeated cumulative process. The cumulative method is being adapted to the purposes of computation, particularly multiplication and division. The operations of multiplication and division are represented by algebraic formulas. An advantage of the method is that the cumulative process can be performed on decimal numbers. The present paper aims to establish a basic and useful formula valid for the two fundamental arithmetic operations of multiplication and division. The new cumulative method proved to be more flexible and made it possible to extend the multiplication and division based on repeated addition/subtraction to decimal numbers. 展开更多
关键词 Multiplication and Division Cumulative Method Repeated Process Decimal Numbers
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Cumulative Air Quality Impacts from Twenty-Two Major Power Plants
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作者 Md M.Karim Navin Bindra Arub Masud 《Journal of Environmental Science and Engineering(A)》 CAS 2024年第1期1-14,共14页
Cumulative assessment is a tool for the project developer to try and take into consideration not only their contribution to cumulative impacts but also other projects and external factors that may place their developm... Cumulative assessment is a tool for the project developer to try and take into consideration not only their contribution to cumulative impacts but also other projects and external factors that may place their developments at risk.This study assessed the cumulative impacts of air emissions from 22 major power plants in southeast Bangladesh planned to generate 21,550 MW of electricity.It also includes anticipated growth in small to medium size industries,brickfields,highway traffic,inland water transport,transhippers,jetty,and vessel transports used for transporting fuel resources for these power plants.A 50 km by 50 km airshed is considered for air quality modeling.Cumulative analysis indicates that predicted MGLCs(Maximum Ground Level Concentrations)of NO2 and CO are complying with both Bangladesh NAAQS(National Ambient Air Quality Standards)and WBG(World Bank Group)Guidelines.The daily average MGLC of PM_(2.5)(62.45µg/m^(3))from all sources complies with NAAQS,however,exceeds the WBG Guidelines.Annual PM_(2.5) concentration(15.45µg/m^(3))exceeds NAAQS and WBG Guidelines.The PM10 concentration complies with the NAAQS for both 24-hour and annual averaging times.Annual average concentration(23.12µg/m^(3))exceeds WBG Guidelines.Daily average SO2 concentration(102.49µg/m^(3))complies with the NAAQS however,it exceeds the WBG guideline values.High concentrations of PM_(2.5) and SO2 are due to the contribution of transboundary emissions and secondary pollutants in the atmosphere.This dispersion modeling outcome can be used by the policymakers for the pollution reduction strategy. 展开更多
关键词 CIA(Cumulative Impact Assessment) dispersion modeling power generation Bangladesh.
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A Machine Learning Classification Model for Detecting Prediabetes
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作者 A. K. M. Raquibul Bashar Mahdi Goudarzi Chris P. Tsokos 《Journal of Data Analysis and Information Processing》 2024年第3期462-478,共17页
The incidence of prediabetes is in a dangerous condition in the USA. The likelihood of increasing chronic and complex health issues is very high if this stage of prediabetes is ignored. So, early detection of prediabe... The incidence of prediabetes is in a dangerous condition in the USA. The likelihood of increasing chronic and complex health issues is very high if this stage of prediabetes is ignored. So, early detection of prediabetes conditions is critical to decrease or avoid type 2 diabetes and other health issues that come as a result of untreated and undiagnosed prediabetes condition. This study is done in order to detect the prediabetes condition with an artificial intelligence method. Data used for this study is collected from the Centers for Disease Control and Prevention’s (CDC) survey conducted by the Division of Health and Nutrition Examination Surveys (DHANES). In this study, several machine learning algorithms are exploited and compared to determine the best algorithm based on Average Squared Error (ASE), Kolmogorov-Smirnov (Youden) scores, areas under the ROC and some other measures of the machine learning algorithm. Based on these scores, the champion model is selected, and Random Forest is the champion model with approximately 89% accuracy. 展开更多
关键词 PREDIABETES Machine Learning SVM FOREST Cumulative Lift
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Application of ACP Nonlinear Math in Analyzing Arithmetic and Radiation Transmission Data (Application 1 & 2) [4-21-2024, 820P] (V)
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作者 Ralph W. Lai Melisa W. Lai-Becker Grace Cheng-Dodge 《Journal of Applied Mathematics and Physics》 2024年第6期2302-2319,共18页
In this study, we explore the application of ACP (asymptotic curve based and proportionality oriented) Alpha Beta (αβ) Nonlinear Math to analyze arithmetic and radiation transmission data. Specifically, we investiga... In this study, we explore the application of ACP (asymptotic curve based and proportionality oriented) Alpha Beta (αβ) Nonlinear Math to analyze arithmetic and radiation transmission data. Specifically, we investigate the relationship between two variables. The novel approach involves collecting elementary “y” data and subsequently analyzing the asymptotic cumulative or demulative (opposite of cumulative) Y data. In part I, we examine the connection between the common linear numbers and ideal nonlinear numbers. In part II, we delve into the relationship between X-ray energy and the radiation transmission for various thin film materials. The fundamental physical law asserts that the nonlinear change in continuous variable Y is negatively proportional to the nonlinear change in continuous variable X, expressed mathematically as dα = −Kdβ. Here: dα {Y, Yu, Yb} represents the change in Y, with Yu and Yb denoting the upper and baseline asymptote of Y. dβ {X, Xu, Xb} represents the change in X, with Xu and Xb denoting the upper and baseline asymptote of X. K represents the proportionality constant or rate constant, which varies based on equation arrangement. K is the key inferential factor for describing physical phenomena. 展开更多
关键词 Asymptotic Concave and Convex Curve Upper and Baseline Asymptote Demulative vs. Cumulative Coefficient of Determination Proportionalityand Position Constant Skewed Bell and Sigmoid Curve
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Estimation of lead and zinc emissions from mineral exploitation based on characteristics of lead/zinc deposits in China 被引量:15
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作者 张秀武 杨林生 +3 位作者 李永华 李海蓉 王五一 葛全胜 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第11期2513-2519,共7页
Nonferrous mining activities are some of the largest sources of heavy metals emissions into the environment and China is one of the largest producers and consumers of lead and zinc in the world.The cumulative producti... Nonferrous mining activities are some of the largest sources of heavy metals emissions into the environment and China is one of the largest producers and consumers of lead and zinc in the world.The cumulative productions and emissions of lead and zinc from mining-related activities in China were estimated.Up to 2007,the cumulative productions of lead and zinc in China were estimated to be about 6.69 and 12.59 Mt,respectively;and about 1.62 Mt lead and 3.32 Mt zinc emitted into the ambient environment during the mining,processing and smelting activities,representing 24.39% and 26.36% cumulative production,respectively.Among these three types of mining-related activities,mineral processing contributes the most to the total emission of 50.67% lead and 45.51% zinc. 展开更多
关键词 lead/zinc deposit LEAD ZINC cumulative production emission flux
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Reliability assessment considering dependent competing failure process and shifting-threshold 被引量:11
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作者 苏春 瞿众洲 郝会兵 《Journal of Southeast University(English Edition)》 EI CAS 2013年第1期52-56,共5页
The reliability assessment problem for products subject to degradation and random shocks is investigated. Two kinds of probabilistic models are constructed, in which the dependent competing failure process is consider... The reliability assessment problem for products subject to degradation and random shocks is investigated. Two kinds of probabilistic models are constructed, in which the dependent competing failure process is considered. First, based on the assumption of cumulative shock, the probabilistic models for hard failure and soft failure are built respectively. On this basis, the dependent competing failure model involving degradation and shock processes is established. Furthermore, the situation of the shifting-threshold is also considered, in which the hard failure threshold value decreases to a lower level after the arrival of a certain number of shocks. A case study of fatigue crack growth is given to illustrate the proposed models. Numerical results show that shock has a significant effect on the failure process; meanwhile, the effect will be magnified when the value of the hard threshold shifts to a lower level. 展开更多
关键词 degradation hard failure dependent competing failure process cumulative shock model shifting-threshold
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Seasonal dynamics of gas regulation service in forest ecosystem 被引量:2
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作者 李士美 谢高地 +2 位作者 于贵瑞 张彩霞 盖力强 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第1期99-103,I0004,共6页
Using the 3-year observational data from ChinaFlux (Chinese Terrestrial Ecosystem Flux Research Network), we studied the gas regulation flux dynamics and cumulative process of gas regulation value in Qianyanzhou mid... Using the 3-year observational data from ChinaFlux (Chinese Terrestrial Ecosystem Flux Research Network), we studied the gas regulation flux dynamics and cumulative process of gas regulation value in Qianyanzhou middle subtropical plantation (QYF) and Changbai Mountain temperate mixed forest (CBF). The gas regulation service was differentiated into vegetation gas regulation service and net ecosystem gas regulation service. Carbon tax approach, reforestation cost approach and industrial oxygen approach were employed to calculate gas regulation value. Results show that there was significant seasonal variation in vegetation gas regulation flux. Daily CO2 uptake fluxes averaged 82.00 kg·ha^-·d^-1 and 59.37 kg·ha^-·d^-1 and the corresponding 02 emission fluxes were 59.65 kg·ha^-·d^-1 and 43.19 kg·ha^-·d^-1 for QYF and CBF, respectively. The cumulative curves of vegetation gas regulation value always followed a sigmoid shape, and the annual gas regulation value produced by vegetation was RMB 14342.69 yuan·ha^-1 and RMB 10384.18 yuan·ha^-1 for both QYF and CBF, respectively. In terms of monthly net ecosystem gas regulation service, QYF appeared as a CO2 sink and O2 source for the whole year, while CBF appeared to be a CO2 sink and O2 source mainly in the period between May and September. The cumulative curves of net ecosystem gas regulation value presented a sigmoid ("S") shape for QYF, while a unimodal type curve for CBF. The annual net ecosystem gas regulation value was 8470.52 yuan·ha^-1 and 5091.98yuan·ha^-1 for QYF and CBF, respectively. The economic value of both the vegetation gas regulation service and net ecosystem gas regulation service were mainly produced between May and October. 展开更多
关键词 gas regulation service flux CUMULATIVE CO2 uptake O2 emission
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