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Glomerular filtration rate and comorbidity factors in elderly hospitalizations 被引量:1
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作者 Hatice Hamarat 《World Journal of Nephrology》 2025年第1期93-98,共6页
BACKGROUND With an increase in the elderly population,the frequency of hospitalizations in recent years has also risen at a rapid pace.This,in turn,has resulted in poor outcomes and costly treatments.Hospitalization r... BACKGROUND With an increase in the elderly population,the frequency of hospitalizations in recent years has also risen at a rapid pace.This,in turn,has resulted in poor outcomes and costly treatments.Hospitalization rates increase in elderly patients due to a decline in glomerular filtration rate(GFR).AIM To investigate the connection between GFR and comorbidity and reasons for hospitalization in elderly patients.METHODS We analyzed patients aged 75 years and over who were admitted to the internal medicine clinic of a tertiary hospital in Eskisehir.At admission,we calculated GFR values using the Modification of Diet in Renal Disease study formula and classified them into six categories:G1,G2,G3a,G3b,G4,and G5.We analyzed associations with hospitalization diagnoses and comorbidity factors.RESULTS The average age of the patients was 80.8 years(±4.5 years).GFR was 57.287±29.5 mL/kg/1.73 m2 in women and 61.3±31.5 mL/kg/1.73 m2 in men(P=0.106).Most patients were admitted to the hospital at G2 stage(32.8%).The main reasons for hospitalization were anemia(34.4%and 28.6%)and malnutrition(20.9%and 20.8%)in women and men,respectively(P=0.078).The most frequent comor-bidity leading to hospitalization was arterial hypertension(n=168,28%),fo-llowed by diabetes(n=166,27.7%)(P=0.001).CONCLUSION When evaluating geriatric patients,low GFR alone does not provide sufficient information.Patients’comorbid factors should also be taken into account.There is no association between low GFR during hospitalization and hospitalization-Hamarat H.Aging and GFR related diagnoses.Knowing the GFR value before hospitalization will be more informative in such studies. 展开更多
关键词 AGING Glomerular filtration rate HOSPITALIZATION COMORBIDITY Elderly hospitalizations
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Strain rate dependence of dynamic recrystallization and texture evolution in hot compressed Mg-Gd-Er-Zr alloy 被引量:1
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作者 Ning Ding Wenbo Du +3 位作者 Shubo Li Ke Liu Xian Du Zijian Yu 《Journal of Magnesium and Alloys》 2025年第1期161-171,共11页
Hot deformation with high strain rate has been paid more attention due to its high efficiency and low cost,however,the strain rate dependent dynamic recrystallization(DRX)and texture evolution in hot deformation proce... Hot deformation with high strain rate has been paid more attention due to its high efficiency and low cost,however,the strain rate dependent dynamic recrystallization(DRX)and texture evolution in hot deformation process,which affect the formability of metals,are lack of study.In this work,the DRX behavior and texture evolution of Mg-8Gd-1Er-0.5Zr alloy hot compressed with strain rates of 0.1 s^(−1),1 s^(−1),10 s^(−1) and 50 s^(−1) are studied,and the corresponding dominant mechanisms for DRX and texture weakening are discussed.Results indicated the DRX fraction was 20%and the whole texture intensity was 16.89 MRD when the strain rate was 0.1 s^(−1),but they were 76%and 6.55 MRD,respectively,when the strain rate increased to 50 s^(−1).The increment of DRX fraction is suggested to result from the reduced DRX critical strain and the increased dislocation density as well as velocity,while the weakened whole texture is attributed to the increased DRX grains.At the low strain rate of 0.1 s^(−1),discontinuous DRX(DDRX)was the dominant,but the whole texture was controlled by the deformed grains with the preferred orientation of{0001}⊥CD,because the number of DDRX grains was limited.At the high strain rate of 50 s^(−1),continuous DRX(CDRX)and twin-induced DRX(TDRX)were promoted,and more DRX grains resulted in orientation randomization.The whole texture was mainly weakened by CDRX and TDRX grains,in which CDRX plays a major role.The results of present work are significant for understanding the hot workability of Mg-RE alloys with a high strain rate. 展开更多
关键词 Dynamic recrystallization Texture Hot compression Strain rate Mg-Gd-Er-Zr alloy
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Md CIb HLH1 modulates sugar metabolism and accumulation in apple fruits by coordinating carbohydrate synthesis and allocation 被引量:1
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作者 Jianqiang Yu Xiaolong Liu +7 位作者 Wenyan Wang Lili Zhang Chukun Wang Quanyan Zhang Jiahui Wang Mengchi Du Lixia Sheng Dagang Hu 《Horticultural Plant Journal》 2025年第2期578-592,共15页
The content of soluble sugars is a vital parameter that indicates the quality of fleshy fruits such as apple(Malus domestica Borkh.).Studying the patterns of accumulation of soluble sugars and regulatory mechanisms as... The content of soluble sugars is a vital parameter that indicates the quality of fleshy fruits such as apple(Malus domestica Borkh.).Studying the patterns of accumulation of soluble sugars and regulatory mechanisms associated with fruit development is crucial for breeding improved fruit varieties.Here,we report that MdCIbHLH1,a low temperature-induced b HLH transcription factor,inhibits the accumulation of soluble sugars by regulating sugar-metabolizing enzyme activities,photosynthetic performance,and the expression of sugar-related genes in developing apple fruits.MdCIbHLH1 inhibits MdFBP and MdPEPCK expression,thus blocking the conversion of acids to sugars in apple fruits.We also discovered that MdCIbHLH1 decreases the photosynthetic rate and carbohydrate accumulation in apple leaves.Our results suggest that soluble sugar accumulation in apple fruits is influenced by multiple factors,including metabolic status,photosynthesis,and carbohydrate allocation.MdCIbHLH1 is critically involved in controlling the accumulation of soluble sugars by coordinating carbohydrate synthesis and allocation,thus influencing sugar transport and its metabolism during the development of apple fruits. 展开更多
关键词 Fruit quality APPLE BHLH Sugar metabolism and transportation Photosynthetic rates
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Influences of strain rate on mechanical behaviors of unsaturated and quasi-saturated loess under varying drainage conditions 被引量:1
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作者 Tongwei Zhang Sheng Li +2 位作者 Hengxing Lan Huyuan Zhang Fanyu Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第2期1163-1181,共19页
Although time-dependent deformation of geomaterials underpins slope-failure prediction models,the influence of strain rate on shearing strength and deformation behavior of loess remains unclear.The consolidated undrai... Although time-dependent deformation of geomaterials underpins slope-failure prediction models,the influence of strain rate on shearing strength and deformation behavior of loess remains unclear.The consolidated undrained(CU)and drained(CD)triaxial testing elucidated the impact of strain rate(0.005–0.3 mm/min)on strength envelopes,deformation moduli,pore pressures,and dilatancy characteristics of unsaturated and quasi-saturated loess.Under drained conditions with a controlled matric suction of 50 kPa,increasing strain rates from 0.005 mm/min to 0.011 mm/min induced decreases in failure deviatoric stress(qf),initial deformation modulus(Ei),and cohesion(c),while friction angles remained unaffected.Specimens displayed initial contractive volumetric strains transitioning to dilation across varying confining pressures.Higher rates diminished contractive volumetric strains and drainage volumes,indicating reduced densification and strength in the shear zone.Under undrained conditions,both unsaturated and quasi-saturated(pore pressure coefficient B=0.75)loess exhibited deteriorating mechanical properties with increasing rates from 0.03 mm/min to 0.3 mm/min.For unsaturated loess,reduced contractive volumetric strains at higher rates manifested relatively looser structures in the pre-peak stress phase.The strength decrement in quasi-saturated loess arose from elevated excess porewater pressures diminishing effective stresses.Negative porewater pressures emerged in quasi-saturated loess at lower confining pressures and strain rates.Compared to previous studies,the qf and Ei exhibited rate sensitivity below threshold values before attaining minima with marginal subsequent influence.The underlying mechanism mirrors the transition from creep to accelerated deformation phase of landslides. 展开更多
关键词 Unsaturated loess Strain rate Shearing strength Deformation modulus Drainage conditions
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Impact behavior and strain rate effects of artificial limestone by MICP 被引量:1
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作者 Yaru Lv Lin Wu +2 位作者 Zhigang Duan Yuchen Su Dongdong Zhang 《Biogeotechnics》 2025年第2期72-80,共9页
Natural cemented calcareous sand and limestone are highly complex and not well understood in terms of the me-chanical behavior due to the difficulty of obtaining undisturbed samples from far sea.This paper proposes an... Natural cemented calcareous sand and limestone are highly complex and not well understood in terms of the me-chanical behavior due to the difficulty of obtaining undisturbed samples from far sea.This paper proposes an artificial method in a laboratory setting using microbial-induced carbonate precipitation(MICP)to simulate the natural process of cementation of limestone.The artificially cemented sand has a high degree of similarity with the natural weakly limestone in three aspects:(1)the mineral composition of the cemented material is also granular calcite and acicular aragonite;(2)the microstructure in interconnected open pore network can be gradually closed and contracted with cementation.The porosity reaches to approximately 9.2%;(3)both the stress-strain relationship and the unconfined strength closely resemble that of natural weakly limestone.Furthermore,both static and dynamic behaviors of artificial limestone were studied by quasi-static compression tests and Split Hopkinson Pressure Bar(SHPB)tests,finding that the unconfined strength of weakly artifical limestone exponentially increases with increasing strain rate.A rate-dependent bond strength was proposed and implemented in software to reveal the mechanism of strain rate effects.It is found that the loading velocity is too high to keep in sync with the initiation and propagation of cracks under impact loading.This delay-induced viscosity may restrict the movement of the surrounding balls,thus increasing resistance. 展开更多
关键词 Weakly limestone MICP artificial cementation Calcareous sand Limestone impact behavior Strain rate effects
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The Mechanism of Heating Rate on the Secondary Recrystallization Evolution in Grain Oriented Silicon Steel
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作者 GAO Qian LI Jun +3 位作者 WANG Xianhui CAO Laifu GONG Jian LI Bo 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2025年第1期275-282,共8页
Grain-oriented silicon steels were prepared at different heating rates during high temperature annealing,in which the evolution of magnetic properties,grain orientations and precipitates were studied.To illustrate the... Grain-oriented silicon steels were prepared at different heating rates during high temperature annealing,in which the evolution of magnetic properties,grain orientations and precipitates were studied.To illustrate the Zener factor,the diameter and number density of precipitates of interrupted testing samples were statistically calculated.The effect of precipitate ripening on the Goss texture and magnetic property was investigated.Data indicated that the trend of Zener factor was similar under different heating rates,first increasing and then decreasing,and that the precipitate maturing was greatly inhibited as the heating rate increased.Secondary recrystallization was developed at the temperature of 1010℃when a heating rate of 5℃/h was used,resulting in Goss,Brass and{110}<227>oriented grains growing abnormally and a magnetic induction intensity of 1.90T.Furthermore,increasing the heating rate to 20℃/h would inhibit the development of undesirable oriented grains and obtain a sharp Goss texture.However,when the heating rate was extremely fast,such as 40℃/h,poor secondary recrystallization was developed with many island grains,corresponding to a decrease in magnetic induction intensity to 1.87 T.At a suitable heating rate of 20℃/h,the sharpest Goss texture and the highest magnetic induction of 1.94 T with an onset secondary recrystallization temperature of 1020℃were found among the experimental variables in this study.The heating rate affected the initial temperature of secondary recrystallization by controlling the maturation of precipitates,leading to the deviation and dispersion of Goss texture,thereby reducing the magnetic properties. 展开更多
关键词 high temperature annealing heating rate secondary recrystallization grain oriented silicon steel
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Graded density impactor design via machine learning and numerical simulation:Achieve controllable stress and strain rate 被引量:1
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作者 Yahui Huang Ruizhi Zhang +6 位作者 Shuaixiong Liu Jian Peng Yong Liu Han Chen Jian Zhang Guoqiang Luo Qiang Shen 《Defence Technology(防务技术)》 2025年第9期262-273,共12页
The graded density impactor(GDI)dynamic loading technique is crucial for acquiring the dynamic physical property parameters of materials used in weapons.The accuracy and timeliness of GDI structural design are key to ... The graded density impactor(GDI)dynamic loading technique is crucial for acquiring the dynamic physical property parameters of materials used in weapons.The accuracy and timeliness of GDI structural design are key to achieving controllable stress-strain rate loading.In this study,we have,for the first time,combined one-dimensional fluid computational software with machine learning methods.We first elucidated the mechanisms by which GDI structures control stress and strain rates.Subsequently,we constructed a machine learning model to create a structure-property response surface.The results show that altering the loading velocity and interlayer thickness has a pronounced regulatory effect on stress and strain rates.In contrast,the impedance distribution index and target thickness have less significant effects on stress regulation,although there is a matching relationship between target thickness and interlayer thickness.Compared with traditional design methods,the machine learning approach offers a10^(4)—10^(5)times increase in efficiency and the potential to achieve a global optimum,holding promise for guiding the design of GDI. 展开更多
关键词 Machine learning Numerical simulation Graded density impactor Controllable stress-strain rate loading Response surface methodology
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On the Relative Growth Rate of the Digits in Sylvester Continued Fraction Expansions
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作者 LV Meiying RAO Guilin 《应用数学》 北大核心 2025年第2期468-476,共9页
For the Sylvester continued fraction expansions of real numbers,FAN et al.(2007)proved that,for almost all real numbers,the nth partial quotient grows exponentially with respect to the product of the first n-1 partial... For the Sylvester continued fraction expansions of real numbers,FAN et al.(2007)proved that,for almost all real numbers,the nth partial quotient grows exponentially with respect to the product of the first n-1 partial quotients.In this paper,we establish the Hausdorff dimension of the exceptional set where the growth rate is a general function. 展开更多
关键词 Sylvester continued fraction expansions Growth rate Hausdorff dimension
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Effect of Withdrawal Rate on Non-uniform Distribution of Eutectic in Ni-based Single Crystal Superalloy Castings
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作者 Zhao Yunxing Yu Jingyi +1 位作者 Ma Dexin Huang Zaiwang 《稀有金属材料与工程》 北大核心 2025年第8期1934-1939,共6页
The microstructure of single crystal superalloy is relatively simple,consisting primarily ofγdendrites andγ/γ′eutectics.During the directional solidification process of Ni-based single crystal superalloys,withdraw... The microstructure of single crystal superalloy is relatively simple,consisting primarily ofγdendrites andγ/γ′eutectics.During the directional solidification process of Ni-based single crystal superalloys,withdrawal rate is a critical parameter affecting the spatial distribution ofγ/γ′eutectic along gravity direction.The results show that theγ/γ′eutectic fraction of the upper platform surface is always higher than that of the lower one,regardless of withdrawal rate.As the withdrawal rate decreases,there is a significant increase inγ/γ′eutectic fraction on the upper surface,while it decreases on the lower surface.The upward accumulation ofγ/γ′eutectic becomes more severe as the withdrawal rate decreases.It is also found that the percentage of Al+Ta is positively correlated with theγ/γ′eutectic fraction.Thermo-solute convection of Al and Ta solutes in the solidification front is the prime reason for the non-uniform distribution of eutectic.The non-uniform distribution ofγ/γ′eutectic cannot be eliminated even after subsequent solution heat treatment,resulting in excess eutectic on the upper surface and thus leading to the scrapping of the blade. 展开更多
关键词 Ni-based single crystal superalloy EUTECTICS withdrawal rate thermo-solute convection
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Equilibrium Strategies in M/M/1 Retrial Queues with Variable Service Rate
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作者 LIU Yuanyuan YAN Zhaozeng YANG Qin 《应用概率统计》 北大核心 2025年第3期448-466,共19页
We consider a single server constant retrial queue,in which a state-dependent service policy is used to control the service rate.Customer arrival follows Poisson process,while service time and retrial time are exponen... We consider a single server constant retrial queue,in which a state-dependent service policy is used to control the service rate.Customer arrival follows Poisson process,while service time and retrial time are exponential distributions.Whenever the server is available,it admits the retrial customers into service based on a first-come first-served rule.The service rate adjusts in real-time based on the retrial queue length.An iterative algorithm is proposed to numerically solve the personal optimal problem in the fully observable scenario.Furthermore,we investigate the impact of parameters on the social optimal threshold.The effectiveness of the results is illustrated by two examples. 展开更多
关键词 variable service rate retrial queues real-time adaptability equilibrium strategies ALGORITHM
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Comparative Effects of Doses of Nauclea latifolia and 17 Alpha Methyltestosterone on Masculinization and Growth Rates of Tilapia Orechromis niloticus Larvae in Senegal
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作者 Mouhamadou Amadou Ly Fafanding Sane +3 位作者 Robane Faye Baboucar Sane Malick Aliou Sene Cheikh Tidiane Ba 《Open Journal of Applied Sciences》 2025年第1期1-12,共12页
One of the main obstacles to the development of aquaculture in Senegal is the availability of fry and juveniles in sufficient quantities. The objective of our study is to evaluate the effects of treatment with the hor... One of the main obstacles to the development of aquaculture in Senegal is the availability of fry and juveniles in sufficient quantities. The objective of our study is to evaluate the effects of treatment with the hormone 17 alpha methyl testosterone (17-&-MT) and different doses of Nauclea latifolia root powder on the masculinization rates of tilapia Oreochromis niloticus larvae in Senegal. A total of 450 larvae of Oreochromis niloticus, with an average size of 0.012 g, were placed in 15 aquariums, each containing 30 individuals and fed one of the 5 diets in triplicate. These individuals were fed either a diet containing a plant extract at a dose of 180 mg (T180), 200 mg (T200) and 250 mg (T250) per kg of food, or a diet containing 60 mg/kg of the hormone 17-&-MT (TMT), or a diet without either the plant extract or the hormone (T0). Individuals were fed for 30 days with the treatment diets, and then with the industrial feed for the rest of the experiment. At the end of the study, the results of the masculinization rate were: 80.49%, 73.13%, 69.23%, 66.67% and 45.95% for T250;T200, TMT, T180 and T0 respectively. In summary, we can say that the 250 mg/kg dose provides better masculinization, followed by 200mg/kg and then 17 α MT. For the plant, the increase in the percentage of males is dose-dependent. These results also translate into better growth of individuals in this order. However, the relatively lower survival rates observed in batches treated with Nauclea latifolia extract indicate that these treatments could have a deleterious effect on the survival of Oreochromis niloticus larvae. These results suggest the use of N. latifolia extract at a dose of 250 mg/kg feed for better production of male O. niloticus larvae without compromising their growth. 展开更多
关键词 Nauclea latifolia Masculinization rate Growth Performance Oreochromis niloticus
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High-precision spot centroid positioning of high-frame-rate short-wave infrared images for satellite laser communication
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作者 FU Peng HE Dao-Gang +1 位作者 LIU Jun WANG Yue-Ming 《红外与毫米波学报》 北大核心 2025年第1期66-77,共12页
The accuracy of spot centroid positioning has a significant impact on the tracking accuracy of the system and the stability of the laser link construction.In satellite laser communication systems,the use of short-wave... The accuracy of spot centroid positioning has a significant impact on the tracking accuracy of the system and the stability of the laser link construction.In satellite laser communication systems,the use of short-wave infrared wavelengths as beacon light can reduce atmospheric absorption and signal attenuation.However,there are strong non-uniformity and blind pixels in the short-wave infrared image,which makes the image distorted and leads to the decrease of spot centroid positioning accuracy.Therefore,the high-precision localization of the spot centroid of the short-wave infrared images is of great research significance.A high-precision spot centroid positioning model for short-wave infrared is proposed to correct for non-uniformity and blind pixels in short-wave infrared images and quantify the localization errors caused by the two,further model-based localization error simulations are performed,and a novel spot centroid positioning payload for satellite laser communications has been designed using the latest 640×512 planar array InGaAs shortwave infrared detector.The experimental results show that the non-uniformity of the corrected image is reduced from 7%to 0.6%,the blind pixels rejection rate reaches 100%,the frame rate can be up to 2000 Hz,and the spot centroid localization accuracy is as high as 0.1 pixel point,which realizes high-precision spot centroid localization of high-frame-frequency short-wave infrared images. 展开更多
关键词 satellite laser communication spot centroid positioning short-wave infrared high frame rate NONUNIFORMITY
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Structure Regulation Engineering for Biomass-Derived Carbon Anodes Enabling High-Rate Dual-Ion Batteries
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作者 Rui Zhou Rui Liu +4 位作者 Yun-Nuo Li Si-Jie Jiang Tian-Tian Jing Yan-Song Xu Fei-Fei Cao 《电化学(中英文)》 北大核心 2025年第8期34-43,共10页
Dual-ion batteries(DIBs)usually use carbon-based materials as electrodes,showing advantages in high operating volt-age,potential low cost,and environmental friendliness.Different from conventional“rocking chair”type... Dual-ion batteries(DIBs)usually use carbon-based materials as electrodes,showing advantages in high operating volt-age,potential low cost,and environmental friendliness.Different from conventional“rocking chair”type secondary batter-ies,DIBs perform a unique working mechanism,which employ both cation and anion taking part in capacity contribution at an anode and a cathode,respectively,during electrochemical reactions.Graphite has been identified as a suitable cathode material for anion intercalation at high voltages(>4.8 V)with fast reaction kinetics.However,the development of DIBs is being hindered by dynamic mismatch between a cathode and an anode due to sluggish Li+diffusion at a high rate.Herein,we prepared phyllostachys edulis derived carbon(PEC)through microstructure regulation strategy and investigated the carbonized temperature effect,which effectively tailored the rich short-range ordered graphite microdomains and disor-dered amorphous regions,as well as a unique nano-pore hierarchical structure.The pore size distribution of nano-pores was concentrated in 0.5-5 nm,providing suitable channels for rapid Li+transportation.It was found that PEC-500(carbon-ized at 500℃)achieved a high capacity of 436 mAh·g^(-1)at 300 mA·g^(-1)and excellent rate performance(maintaining a high capacity of 231 mAh·g^(-1)at 3 A·g^(-1)).The assembled dual-carbon PEC-500||graphite full battery delivered 114 mAh·g^(-1)at 10 C with 96%capacity retention after 3000 cycles and outstanding rate capability,providing 74 mAh·g^(-1)at 50 C. 展开更多
关键词 Dual-ion battery Biomass hard carbon Structural regulation High operating voltage High rate
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Optimal Investment Strategy for an Insurer in Two Currency Markets
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作者 ZHOU Qianqian 《应用概率统计》 北大核心 2025年第1期1-16,共16页
In this paper,we study the optimal investment problem of an insurer whose surplus process follows the diffusion approximation of the classical Cramer-Lundberg model.Investment in the foreign markets is allowed,and the... In this paper,we study the optimal investment problem of an insurer whose surplus process follows the diffusion approximation of the classical Cramer-Lundberg model.Investment in the foreign markets is allowed,and therefore,the foreign exchange rate model is incorporated.Under the allowing of selling and borrowing,the problem of maximizing the expected exponential utility of terminal wealth is studied.By solving the corresponding Hamilton-Jacobi-Bellman equations,the optimal investment strategies and value functions are obtained.Finally,numerical analysis is presented. 展开更多
关键词 Cramer-Lundberg model exponential utility Hamilton-Jacobi-Bellman equation optimal investment strategy foreign exchange rate
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Design and Dynamic Experiment of Al-Cu Graded Materials Impactor with Strain Rate of 10^(4)–10^(5)/s
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作者 Hu Jianian Zhou Zizheng +4 位作者 Li Yidi Chen Xiang Yang Gang Liu Jintao Zhang Jian 《稀有金属材料与工程》 北大核心 2025年第3期581-586,共6页
Based on simplified calculations of one-dimensional wave systems,loading pressure platform curves of Al-Cu gradient materials(GMs)impactor were designed.The Al-Cu GMs were prepared using tape-pressing sintering,and th... Based on simplified calculations of one-dimensional wave systems,loading pressure platform curves of Al-Cu gradient materials(GMs)impactor were designed.The Al-Cu GMs were prepared using tape-pressing sintering,and their acoustic properties were characterized to match the design path.The parallelism of the Al-Cu GM was confirmed using a three-dimensional surface profilometry machine.A one-stage light-gas gun was used to launch the Al-Cu GM,impacting an Al-LiF target at a velocity of 400 m/s.The results of the experimental strain rate demonstrate that the Al-Cu GMs can realize the precise control of the strain rate within the range of 10^(4)‒10^(5)/s in the high-speed impact experiments. 展开更多
关键词 high strain rate Al-Cu graded materials IMPACTOR acoustic impedance gas gun experiment
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An effective approach for correlating Na^(+) concentrations with sweating rates in wearable sweat sensing platform
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作者 Anwei He Xiaohe Wang +6 位作者 Liang Zhang Haolong Zhang Xingli Xu Chenyang Yu Yongquan Ma Wei Wei Pengfei Niu 《Nanotechnology and Precision Engineering》 2025年第1期58-67,共10页
Accurately correlating the sweating rate and the concentration of biomarkers in sweat is essential in many sweat-based diagnostic applications.These two measurements are always done simultaneously in wearable sweat se... Accurately correlating the sweating rate and the concentration of biomarkers in sweat is essential in many sweat-based diagnostic applications.These two measurements are always done simultaneously in wearable sweat sensing platforms.However,concentration measurements of biomarkers are always delayed on the timeline compared with their production,whereas there is no such delay for sweating rate.Thus,a timeline mismatch exists between these two measurements.This means that the concentration vs rate correlation constructed on the basis of such measurements will deviate from the actual correlation.This study demonstrates the existence of this mismatch and explains its cause using sweat Na^(+)measurements.It also proposes an effective approach that applies a point-by-point compensation for the delay between Na+measurements and the real-time sweating rates,such that the data on the repositioned concentration vs time curve correspond to exactly the same point on the timeline as their production.A vison sensor is developed to measure the sweating rate with high accuracy at a frequency of more than 0.1 Hz.Off-body and on-body measurements of sweating rate and Na^(+)concentration are carried out,and concentration–rate correlations are constructed using both measured and repositioned concentration curves.The least squares and random forest methods are employed to fit the constructed correlations and evaluate the reliability of the proposed approach.The use of the repositioned concentration curve gives a constructed correlation that is much closer to the actual one.This study indicates the necessity to rearrange sensor-measured biomarker concentration vs time curves when correlations of concentration with sweating rate need to be constructed and proposes a practical point-by-point data repositioning strategy for doing so.The results presented here will benefit the study of sweat biomarkers with unclear correlations with sweating rate,as well as providing a basis for the development of more reliable sweat-based diagnostic methods. 展开更多
关键词 Wearable sweat monitoring Sweating rate Concentration rate correlation Timeline mismatch Machine learning
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Effect of Qi-based mindfulness therapy for mild-to-moderate depression
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作者 Qiong-Wei Li Yan Yang +2 位作者 Xue-Jiao Gao Alexander Ma Wei Sun 《World Journal of Psychiatry》 2025年第4期178-185,共8页
BACKGROUND Depression is a disorder characterized by significant and persistent depressed mood,cognitive impairment,impaired voluntary activity,working memory,and somatic symptoms.AIM To determine the efficacy of Qi-b... BACKGROUND Depression is a disorder characterized by significant and persistent depressed mood,cognitive impairment,impaired voluntary activity,working memory,and somatic symptoms.AIM To determine the efficacy of Qi-based mindfulness therapy(QMT)in treating anxiety,depression,and sleep disturbances in individuals with mild-to-moderate depression.METHODS A self-controlled before–after trial was conducted.The study invited online participants for recruitment between May and July 2023.Participants(n=18)aged 18-65 years with mild-to-moderate depression,who were receiving QMT training for 4 weeks,were included.The primary efficacy indicators were the 17 Hamilton Depression Rating Scale and Hamilton Anxiety Scale scores.The secondary outcome indicators included the Zung Self-rating Depression Scale,the self-rating Anxiety Scale,and the Insomnia Severity Index.Pre-and postintervention assessments were conducted.The patients’symptoms related to depression,anxiety,and insomnia were reassessed 4 weeks after the post-intervention evaluation.RESULTS Patients who underwent the QMT intervention for 4 weeks exhibited a statistically significant reduction in scores on the 17 Hamilton Depression Rating Scale,Hamilton Anxiety Scale,the Zung Self-Rating Depression Scale,the Self-Rating Anxiety Scale,and the Insomnia Severity Index relative to their pre-intervention scores(all P<0.05).CONCLUSION QMT training for 4 weeks is an effective nonpharmacological treatment for symptoms of depression,anxiety,and insomnia among patients with mild-to-moderate depression. 展开更多
关键词 Qi-based mindfulness therapy DEPRESSION ANXIETY Insomnia Depression rating scale Anxiety rating scale
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Coulomb stressing rate changes and seismicity dynamics associated with slow slip events in south-central Alaska
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作者 ShanShan Li XingLei Li Bing Xu 《Earth and Planetary Physics》 2025年第2期289-308,共20页
Two long-term slow slip events(SSEs) in Lower Cook Inlet, Alaska, were identified by Li SS et al.(2016). The earlier SSE lasted at least 9 years with M_(w) ~7.8 and had an average slip rate of ~82 mm/year. The latter ... Two long-term slow slip events(SSEs) in Lower Cook Inlet, Alaska, were identified by Li SS et al.(2016). The earlier SSE lasted at least 9 years with M_(w) ~7.8 and had an average slip rate of ~82 mm/year. The latter SSE, occurring in a similar area, lasted approximately 2 years with M_(w) ~7.2 and an average slip rate of ~91 mm/year. To test whether these SSEs triggered earthquakes near the slow slip area, we calculated the Coulomb stressing rate changes on receiver faults by using two fault geometry definitions: nodal planes of focal mechanism solutions of past earthquakes, and optimally oriented fault planes. Regions in the shallow slab(30–60 km) that experienced a significant increase in the Coulomb stressing rate due to slip by the SSEs showed an increase in seismicity rates during SSE periods. No correlation was found in the volumes that underwent a significant increase in the Coulomb stressing rate during the SSE within the crust and the intermediate slab. We modeled variations in seismicity rates by using a combination of the Coulomb stress transfer model and the framework of rate-and-state friction. Our model indicated that the SSEs increased the Coulomb stress changes on adjacent faults,thereby increasing the seismicity rates even though the ratio of the SSE stressing rate to the background stressing rate was small. Each long-term SSE in Alaska brought the megathrust updip of the SSE areas closer to failure by up to 0.1–0.15 MPa. The volumes of significant Coulomb stress changes caused by the Upper and Lower Cook Inlet SSEs did not overlap. 展开更多
关键词 slow slip events Coulomb stressing rate change seismicity rate change receiver fault rate–state stress transfer model seismogenic zone megathrust failure
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Determinants of high sessile serrated lesion detection:Role of faecal occult blood test and colonoscopy quality indicators
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作者 Harry Williams Natalie R Dierick +2 位作者 Christina Lee Praka Sundaralingam Stuart N Kostalas 《World Journal of Gastrointestinal Endoscopy》 2025年第8期79-90,共12页
BACKGROUND Sessile serrated lesions(SSLs)are premalignant polyps implicated in up to 30%of colorectal cancers.Australia reports high SSL detection rates(SSL-DRs),yet with marked variability(3.1%-24%).This substantial ... BACKGROUND Sessile serrated lesions(SSLs)are premalignant polyps implicated in up to 30%of colorectal cancers.Australia reports high SSL detection rates(SSL-DRs),yet with marked variability(3.1%-24%).This substantial variation raises concerns about missed lesions and post-colonoscopy colorectal cancer.This study investigates determinants associated with SSL-DR variation in regional Australia.AIM To study how patient,clinical,and colonoscopy factors are associated with SSL detection in a regional Australian practice.We aimed to contribute high-detection data to the literature by analyzing the association of SSL detection with various determinants.METHODS This retrospective,cross-sectional analysis examined 1450 colonoscopies performed at Port Macquarie Gastroenterology during 2023.Sigmoidoscopies and repeat procedures were excluded.Multivariate logistic regression analyzed associations between SSL detection and patient demographics,clinical indications,procedural factors,and comorbidities.RESULTS The overall SSL-DR was 30.7%.Multivariate analysis identified several independent predictors:Clinical indication,bowel preparation quality,inflammatory bowel disease status,and serrated polyposis syndrome.The faecal occult blood test positive(FOBT)(+)cohort showed the highest predicted SSL detection probability(39.8%),while clinical symptoms showed the lowest(22.3%).After adjustment,SSL detection odds were 2.3 times greater among FOBT(+)patients than those with clinical symptoms(adjusted odds ratio=2.30,95%confidence interval:1.20-4.40,P=0.004).CONCLUSION SSL-DR as a quality indicator requires contextualization regarding clinical indications,bowel preparation quality,and comorbidities.There was a significantly higher prevalence of SSLs in FOBT(+)patients.Despite comprehensive adjustment,this study cannot fully explain the wide SSL-DR variation in Australia,highlighting the need for standardized detection protocols and further research to ensure optimal cancer prevention outcomes. 展开更多
关键词 Sessile serrated lesion Adenoma detection rate Faecal occult blood test Polyp detection rate DYSPLASIA COLONOSCOPY PREVALENCE
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A review of the experimental and numerical studies on the compression behavior of the additively produced metallic lattice structures at high and low strain rates
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作者 Muhammad Arslan Bin Riaz Mustafa Guden 《Defence Technology(防务技术)》 2025年第7期1-49,共49页
Recent advances in additive manufacturing have enabled the construction of metallic lattice structures with tailored mechanical and functional properties.One potential application of metallic lattice struc-tures is in... Recent advances in additive manufacturing have enabled the construction of metallic lattice structures with tailored mechanical and functional properties.One potential application of metallic lattice struc-tures is in the impact load mitigation where an external kinetic energy is absorbed by the deformation/crushing of lattice cells.This has motivated a growing number of experimental and numerical studies,recently,on the crushing behavior of additively produced lattice structures.The present study overviews the dynamic and quasi-static crushing behavior of additively produced Ti64,316L,and AlSiMg alloy lattice structures.The first part of the study summarizes the main features of two most commonly used additive processing techniques for lattice structures,namely selective-laser-melt(SLM)and electro-beam-melt(EBM),along with a description of commonly observed process induced defects.In the second part,the deformation and strain rate sensitivities of the selected alloy lattices are outlined together with the most widely used dynamic test methods,followed by a part on the observed micro-structures of the SLM and EBM-processed Ti64,316L and AlSiMg alloys.Finally,the experimental and numerical studies on the quasi-static and dynamic compression behavior of the additively processed Ti64,316L,and AlSiMg alloy lattices are reviewed.The results of the experimental and numerical studies of the dynamic properties of various types of lattices,including graded,non-uniform strut size,hollow,non-uniform cell size,and bio-inspired,were tabulated together with the used dynamic testing methods.The dynamic tests have been noted to be mostly conducted in compression Split Hopkinson Pressure Bar(SHPB)or Taylor-and direct-impact tests using the SHPB set-up,in all of which relatively small-size test specimens were tested.The test specimen size effect on the compression behavior of the lattices was further emphasized.It has also been shown that the lattices of Ti64 and AlSiMg alloys are relatively brittle as compared with the lattices of 316L alloy.Finally,the challenges associated with modelling lattice structures were explained and the micro tension tests and multi-scale modeling techniques combining microstructural characteristics with macroscopic lattice dynamics were recommended to improve the accuracy of the numerical simulations of the dynamic compression deformations of metallic lattice structures. 展开更多
关键词 Metallic lattice structures Additive manufacturing Strain rate sensitivity MICROSTRUCTURE Dynamic compression High strain rate loading MODELLING
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