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Reference values of gait parameters in healthy Chinese university students: A cross-sectional observational study
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作者 Jin-Sheng Yu Chen Zhuang +10 位作者 Wen-Xuan Guo Jun-Jie Chen Xiang-Ke Wu Wei Xie Xing Zhou Hui Su Yi-Xuan Chen Li-Kang Wang Wen-Kai Li Kun Tian Ru-Jie Zhuang 《World Journal of Clinical Cases》 SCIE 2023年第29期7061-7074,共14页
BACKGROUND Gait is influenced by race,age,and diseases type.Reference values for gait are closely related to numerous health outcomes.To gain a comprehensive understanding of gait patterns,particularly in relation to ... BACKGROUND Gait is influenced by race,age,and diseases type.Reference values for gait are closely related to numerous health outcomes.To gain a comprehensive understanding of gait patterns,particularly in relation to race-related pathologies and disorders,it is crucial to establish reference values for gait in daily life considering sex and age.Therefore,our objective was to present sex and age-based reference values for gait in daily life,providing a valuable foundation for further research and clinical applications.AIM To establish reference values for lower extremity joint kinematics and kinetics during gait in asymptomatic adult women and men.METHODS Spatiotemporal,kinematics and kinetics parameters were measured in 171 healthy adults(70 males and 101 females)using the computer-aided soft tissue foot model.Full curve statistical parametric mapping was performed using independent and paired-samples t-tests.RESULTS Compared with females,males required more time(cycle time,double-limb support time,stance time,swing time,and stride time),and the differences were statistically significant.In addition,the step and stride lengths of males were longer.Compared to males,female cadence was faster,and statures-per-second and stride-per-minute were higher.There were no statistical differences in speed and stride width between the two groups.After adjusting for height,it was observed that women walked significantly faster than men,and they also had a higher cadence.However,in terms of step length,stride length,and stride width,both genders exhibited similarities.CONCLUSION We established reference values for gait speed and spatiotemporal gait parameters in Chinese university students.This contributes to a valuable database for gait assessment and evaluation of preventive or rehabilitative programs. 展开更多
关键词 Gait analysis GAIT Reference values Spatiotemporal parameters KINEMATICS Chinese
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Parameter-Free Shifted Laplacian Reconstruction for Multiple Kernel Clustering
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作者 Xi Wu Zhenwen Ren F.Richard Yu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第4期1072-1074,共3页
Dear Editor,This letter proposes a parameter-free multiple kernel clustering(MKC)method by using shifted Laplacian reconstruction.Traditional MKC can effectively cluster nonlinear data,but it faces two main challenges... Dear Editor,This letter proposes a parameter-free multiple kernel clustering(MKC)method by using shifted Laplacian reconstruction.Traditional MKC can effectively cluster nonlinear data,but it faces two main challenges:1)As an unsupervised method,it is up against parameter problems which makes the parameters intractable to tune and is unfeasible in real-life applications;2)Only considers the clustering information,but ignores the interference of noise within Laplacian. 展开更多
关键词 parameter LETTER parameter
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Critical Opalescence and Its Impact on the Jet Quenching Parameter q
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作者 武警 曹杉杉 李峰 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第3期23-29,共7页
Jet quenching parameter q is essential for characterizing the interaction strength between jet partons and nuclear matter.Based on the quark-meson model,we develop a new framework for calculating q at finite chemical ... Jet quenching parameter q is essential for characterizing the interaction strength between jet partons and nuclear matter.Based on the quark-meson model,we develop a new framework for calculating q at finite chemical potentials,in which q is related to the spectral function of the chiral order parameter. 展开更多
关键词 parameter QUARK CALCULATING
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Interaction between systemic iron parameters and left ventricular structure and function in the preserved ejection fraction population:a two-sample bidirectional Mendelian randomization study
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作者 Xiong-Bin MA Yong-Ming LIU +1 位作者 Yan-Lin LV Lin QIAN 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2024年第1期64-80,共17页
BACKGROUND Left ventricular(LV)remodeling and diastolic function in people with heart failure(HF)are correlated with iron status;however,the causality is uncertain.This Mendelian randomization(MR)study investigated th... BACKGROUND Left ventricular(LV)remodeling and diastolic function in people with heart failure(HF)are correlated with iron status;however,the causality is uncertain.This Mendelian randomization(MR)study investigated the bidirectional causal relationship between systemic iron parameters and LV structure and function in a preserved ejection fraction population.METHODS Transferrin saturation(TSAT),total iron binding capacity(TIBC),and serum iron and ferritin levels were extracted as instrumental variables for iron parameters from meta-analyses of public genome-wide association studies.Individuals without myocardial infarction history,HF,or LV ejection fraction(LVEF)<50%(n=16,923)in the UK Biobank Cardiovascular Magnetic Resonance Imaging Study constituted the outcome dataset.The dataset included LV end-diastolic volume,LV endsystolic volume,LV mass(LVM),and LVM-to-end-diastolic volume ratio(LVMVR).We used a two-sample bidirectional MR study with inverse variance weighting(IVW)as the primary analysis method and estimation methods using different algorithms to improve the robustness of the results.RESULTS In the IVW analysis,one standard deviation(SD)increased in TSAT significantly correlated with decreased LVMVR(β=-0.1365;95%confidence interval[CI]:-0.2092 to-0.0638;P=0.0002)after Bonferroni adjustment.Conversely,no significant relationships were observed between other iron and LV parameters.After Bonferroni correction,reverse MR analysis showed that one SD increase in LVEF significantly correlated with decreased TSAT(β=-0.0699;95%CI:-0.1087 to-0.0311;P=0.0004).No heterogeneity or pleiotropic effects evidence was observed in the analysis.CONCLUSIONS We demonstrated a causal relationship between TSAT and LV remodeling and function in a preserved ejection fraction population. 展开更多
关键词 FRACTION function parameterS
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Chronic Hepatitis B Virus Infection: Biological Parameters in Patients Treated with Tenofovir Disoproxil Fumarate
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作者 Sanra Déborah Sanogo Moussa Y. Dicko +10 位作者 Lamine N’Diaye Ousmane Diarra Drissa Katilé Abdoulaye Maiga Ouatou Mallé Sabine Drabo Makan S. Tounkara Hourouma Sow Kadiatou Doumbia Anselme Konaté Moussa T. Diarra 《Open Journal of Gastroenterology》 CAS 2024年第4期145-151,共7页
Chronic hepatitis B causes a liver disease characterized by inflammation of the liver parenchyma. The aim of this study was to investigate the evolution of biological parameters in patients treated with Tenofovir for ... Chronic hepatitis B causes a liver disease characterized by inflammation of the liver parenchyma. The aim of this study was to investigate the evolution of biological parameters in patients treated with Tenofovir for chronic B infection at the Commune V referral health center in Bamako. We obtained a prevalence of 14.15%. The most represented age group was 31 - 40 years, with 36.8%. The sex ratio was 1.44 in favour of men. Viral load was undetectable after 18 months of treatment in 25 patients (42.37%). Tenofovir, the 1st-line drug in Mali, is effective on the biological parameters monitored in patients. 展开更多
关键词 Viral Hepatitis B TENOFOVIR Biological parameters
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Study on the clogging mechanism of punching screen in sand control by the punching structure parameters
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作者 Fu-Cheng Deng Fu-Lin Gui +5 位作者 Bai-Tao Fan Lei Wen Sheng-Hong Chen Ning Gong Yun-Chen Xiao Zhi-Hui Xu 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期609-620,共12页
As an independent sand control unit or a common protective shell of a high-quality screen,the punching screen is the outermost sand retaining unit of the sand control pipe which is used in geothermal well or oil and g... As an independent sand control unit or a common protective shell of a high-quality screen,the punching screen is the outermost sand retaining unit of the sand control pipe which is used in geothermal well or oil and gas well.However,most screens only consider the influence of the internal sand retaining medium parameters in the sand control performance design while ignoring the influence of the plugging of the punching screen on the overall sand retaining performance of the screen.To explore the clogging mechanism of the punching screen,this paper established the clogging mechanism calculation model of a single punching screen sand control unit by using the computational fluid mechanics-discrete element method(CFD-DEM)combined method.According to the combined motion of particles and fluids,the influence of the internal flow state on particle motion and accumulation was analyzed.The results showed that(1)the clogging process of the punching sand control unit is divided into three stages:initial clogging,aggravation of clogging and stability of clogging.In the initial stage of blockage,coarse particles form a loose bridge structure,and blockage often occurs preferentially at the streamline gathering place below chamfering inside the sand control unit.In the stage of blockage intensification,the particle mass develops into a relatively complete sand bridge,which develops from both ends of the opening to the center of the opening.In the stable plugging stage,the sand deposits show a“fan shape”and form a“V-shaped”gully inside the punching slot element.(2)Under a certain reservoir particle-size distribution,The slit length and opening height have a large influence on the permeability and blockage rate,while the slit width size has little influence on the permeability and blockage rate.The microscopic clogging mechanism and its law of the punching screen prevention unit are proposed in this study,which has some field guidance significance for the design of punching screen and sand prevention selection. 展开更多
关键词 Punching screen Plugging CFD-DEM Size parameter Sand control
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Adjuvant Rectal Diclofenac for Post Operative Analgesia after Caesarean Section—A Randomized Controlled Study
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作者 Eziaha Eric S. Ede Ayodele A. Olaleye +4 位作者 John C. Irechukwu Uchenna Nelson Nwaedu Borniface N. Ejikeme Vincent Chidiebere Ali Bartholomew I. Olinya 《Open Journal of Obstetrics and Gynecology》 2024年第4期591-609,共19页
BACKGROUND: Pain management following caesarean section still remains a challenge in our environment. Most potent analgesics are either not readily available or expensive. Diclofenac suppository is an NSAID that can b... BACKGROUND: Pain management following caesarean section still remains a challenge in our environment. Most potent analgesics are either not readily available or expensive. Diclofenac suppository is an NSAID that can be used for postoperative analgesia. It is available and affordable. OBJECTIVE: To compare the efficacy and safety of combined rectal diclofenac and intramuscular pentazocine with intramuscular pentazocine alone for post operative pain control following lower segment caesarean section. METHODOLOGY: A total of 120 women who met the selection criteria scheduled for caesarean section under spinal anaesthesia with bupivacaine were randomized into two equal groups to receive either 75 mg diclofenac suppository 12 hourly for 24 hours or one anusol suppository (the placebo) 12 hourly for 24 hours. Both groups received pentazocine as primary analgesia. RESULT: The primary outcome measure is the proportion of patients with severe pain at 24 hours using the visual analogue rating scale. Secondary outcome measures are the time from surgery to ambulation, Passage of flatus, maternal satisfaction and presence of complications. Statistical analysis was done using spss version 22 and graph pad statistical package. Student T-test was used for continuous variables whereas chi square was used for categorical variables P CONCLUSION: Adjuvant rectal diclofenac is superior to pentazocine alone in the management of pain after caesarean section. Less number of patients had moderate to severe pain at 24 hours post operation. Maternal satisfaction in relation to pain management is better with diclofenac suppository. The levels of complications were comparable in both groups. 展开更多
关键词 PAIN Caesarean section DICLOFENAC PLACEBO SUPPOSITORY
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Quaternion-Based Adaptive Trajectory Tracking Control of a Rotor-Missile with Unknown Parameters Identification
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作者 Jie Zhao Zhongjiao Shi +1 位作者 Yuchen Wang Wei Wang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期375-386,共12页
This paper investigates the adaptive trajectory tracking control problem and the unknown parameter identification problem of a class of rotor-missiles with parametric system uncertainties.First,considering the uncerta... This paper investigates the adaptive trajectory tracking control problem and the unknown parameter identification problem of a class of rotor-missiles with parametric system uncertainties.First,considering the uncertainty of structural and aerodynamic parameters,the six-degree-of-freedom(6Do F) nonlinear equations describing the position and attitude dynamics of the rotor-missile are established,respectively,in the inertial and body-fixed reference frames.Next,a hierarchical adaptive trajectory tracking controller that can guarantee closed-loop stability is proposed according to the cascade characteristics of the 6Do F dynamics.Then,a memory-augmented update rule of unknown parameters is proposed by integrating all historical data of the regression matrix.As long as the finitely excited condition is satisfied,the precise identification of unknown parameters can be achieved.Finally,the validity of the proposed trajectory tracking controller and the parameter identification method is proved through Lyapunov stability theory and numerical simulations. 展开更多
关键词 Rotor-missile Adaptive control parameter identification Quaternion control
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State-selective charge exchange cross sections in collisions of highly-charged sulfur ions with helium and molecular hydrogen
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作者 朱小龙 崔述成 +9 位作者 邢大地 徐佳伟 B.Najjari 赵冬梅 郭大龙 高永 张瑞田 苏茂根 张少锋 马新文 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期29-33,共5页
The state-selective cross section data are useful for understanding and modeling the x-ray emission in celestial observations.In the present work,using the cold target recoil ion momentum spectroscopy,for the first ti... The state-selective cross section data are useful for understanding and modeling the x-ray emission in celestial observations.In the present work,using the cold target recoil ion momentum spectroscopy,for the first time we investigated the state-selective single electron capture processes for S^(q+)–He and H_(2)(q=11–15)collision systems at an impact energy of q×20 keV and obtained the relative state-selective cross sections.The results indicate that only a few principal quantum states of the projectile energy level are populated in a single electron capture process.In particular,the increase of the projectile charge state leads to the population of the states with higher principal quantum numbers.It is also shown that the experimental averaged n-shell populations are reproduced well by the over-barrier model.The database is openly available in Science Data Bank at 10.57760/sciencedb.j00113.00091. 展开更多
关键词 highly charged sulfur ion charge exchange state-selective cross sections COLTRIMS
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Effect of Single- versus Double-Layer Uterine Closure during Caesarean Section on Niche Formation and Menstrual Irregularity
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作者 Mohamed Samy Esraa Hussein Fouad Ghoneimy Walid Hitler 《Open Journal of Obstetrics and Gynecology》 2024年第1期57-68,共12页
Background: The myometrium at the location of the CS (caesarean section) scars, also known as residual myometrium thickness (RMT), is larger after a double-layer uterine closure procedure than following a single-layer... Background: The myometrium at the location of the CS (caesarean section) scars, also known as residual myometrium thickness (RMT), is larger after a double-layer uterine closure procedure than following a single-layer one. It may lessen the formation of a niche that is the myometrium’s disruption at the location of the scar of the uterus. Gynecological manifestations, obstetric problems in a future pregnancy and birth, and maybe subfertility are linked to thin RMT and a niche. Objective: To ascertain if double-layer unlocked closure of the uterus is better than single-layer one in terms of post-menstrual spotting and niche development following a first CS. Patients and Methods: In this randomized clinical study, 287 patients were evaluated for qualifying. Of all eligible individuals, 57 patients were excluded from the study based on the inclusion criteria. Results: The variation in ages, gestational age, body mass index (BMI), and cesarean section indications between the two assigned groups is statistically insignificant. However, postmenstrual spotting was statistically significantly more common in single-layer group compared to in double-group. The current study revealed ultrasound findings suggestive of niche formation was statistically significantly more common in single-layer group compared to in double-layer group. Conclusion: As evident from the current study, it demonstrates the advantages of double-layer unlocked closure of the uterus over single-layer one in terms of post-menstrual spotting and niche development following first-time cs. Thus, we deduced that fewer niches are formed, and fewer menstrual spotting occurs in the presence of double unlocked layers closure. To ascertain the impact of uterus closure method on post-operative niche development and the risk of obstetrics and gynaecological problems, further prospective trials with extended follow-up periods are required. 展开更多
关键词 SINGLE-LAYER Double Caesarean section Residual Myometrium Thickness
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THE LOGARITHMIC SOBOLEV INEQUALITY FOR A SUBMANIFOLD IN MANIFOLDS WITH ASYMPTOTICALLY NONNEGATIVE SECTIONAL CURVATURE
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作者 东瑜昕 林和子 陆琳根 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期189-194,共6页
In this note,we prove a logarithmic Sobolev inequality which holds for compact submanifolds without a boundary in manifolds with asymptotically nonnegative sectional curvature.Like the Michale-Simon Sobolev inequality... In this note,we prove a logarithmic Sobolev inequality which holds for compact submanifolds without a boundary in manifolds with asymptotically nonnegative sectional curvature.Like the Michale-Simon Sobolev inequality,this inequality contains a term involving the mean curvature. 展开更多
关键词 asymptotically nonnegative sectional curvature logarithmic Sobolev inequality ABP method
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Absolute partial and total ionization cross sections of carbon monoxide with electron collision from 350 eV to 8000 eV
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作者 Taj Wali Khan 黄伟哲 +2 位作者 王恩亮 单旭 陈向军 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期459-464,共6页
The absolute partial and total cross sections for electron impact ionization of carbon monoxide are reported for electron energies from 350 eV to 8000 eV.The product ions(CO^(+),C^(+),O^(+),CO^(2+),C^(2+),and O^(2+))a... The absolute partial and total cross sections for electron impact ionization of carbon monoxide are reported for electron energies from 350 eV to 8000 eV.The product ions(CO^(+),C^(+),O^(+),CO^(2+),C^(2+),and O^(2+))are measured by employing an ion imaging mass spectrometer and two ion-pair dissociation channels(C^(+)+O^(+)and C^(2+)+O^(+))are identified.The absolute cross sections for producing individual ions and their total,as well as for the ion-pair dissociation channels are obtained by normalizing the data of CO^(+)to that of Ar^(+)from CO-Ar mixture target with a fixed 1:1 ratio.The overall errors are evaluated by considering various kinds of uncertainties.A comprehensive comparison is made with the available data,which shows a good agreement with each other over the energy ranges that are overlapped.This work presents new cross-section data with electron energies above 1000 eV. 展开更多
关键词 electron impact ionization cross sections carbon monoxide ion imaging mass spectrometer
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Observer-based dynamic event-triggered control for distributed parameter systems over mobile sensor-plus-actuator networks
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作者 穆文英 庄波 邱芳 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期237-243,共7页
We develop a policy of observer-based dynamic event-triggered state feedback control for distributed parameter systems over a mobile sensor-plus-actuator network.It is assumed that the mobile sensing devices that prov... We develop a policy of observer-based dynamic event-triggered state feedback control for distributed parameter systems over a mobile sensor-plus-actuator network.It is assumed that the mobile sensing devices that provide spatially averaged state measurements can be used to improve state estimation in the network.For the purpose of decreasing the update frequency of controller and unnecessary sampled data transmission, an efficient dynamic event-triggered control policy is constructed.In an event-triggered system, when an error signal exceeds a specified time-varying threshold, it indicates the occurrence of a typical event.The global asymptotic stability of the event-triggered closed-loop system and the boundedness of the minimum inter-event time can be guaranteed.Based on the linear quadratic optimal regulator, the actuator selects the optimal displacement only when an event occurs.A simulation example is finally used to verify that the effectiveness of such a control strategy can enhance the system performance. 展开更多
关键词 distributed parameter systems event-triggered control mobile sensors mobile actuators
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Parameter estimation in n-dimensional massless scalar field
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作者 杨颖 荆继良 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期231-237,共7页
Quantum Fisher information(QFI)associated with local metrology has been used to parameter estimation in open quantum systems.In this work,we calculated the QFI for a moving Unruh-DeWitt detector coupled with massless ... Quantum Fisher information(QFI)associated with local metrology has been used to parameter estimation in open quantum systems.In this work,we calculated the QFI for a moving Unruh-DeWitt detector coupled with massless scalar fields in n-dimensional spacetime,and analyzed the behavior of QFI with various parameters,such as the dimension of spacetime,evolution time,and Unruh temperature.We discovered that the QFI of state parameter decreases monotonically from 1 to 0 over time.Additionally,we noted that the QFI for small evolution times is several orders of magnitude higher than the QFI for long evolution times.We also found that the value of QFI decreases at first and then stabilizes as the Unruh temperature increases.It was observed that the QFI depends on initial state parameterθ,and Fθis the maximum forθ=0 orθ=π,Fφis the maximum forθ=π/2.We also obtain that the maximum value of QFI for state parameters varies for different spacetime dimensions with the same evolution time. 展开更多
关键词 quantum Fisher information parameter estimation open quantum systems
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Digital measuring the ocular morphological parameters of guinea pig eye in vivo with Python
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作者 Yue Di Zhong-Bao Qiao +4 位作者 Hai-Yun Ye Xin-Yue Li Wen-Ting Luo Wang-Yi Fang Tong Qiao 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第2期239-246,共8页
AIM:To quantitatively measure ocular morphological parameters of guinea pig with Python technology.METHODS:Thirty-six eyeballs of eighteen 3-weekold guinea pigs were measured with keratometer and photographed to obtai... AIM:To quantitatively measure ocular morphological parameters of guinea pig with Python technology.METHODS:Thirty-six eyeballs of eighteen 3-weekold guinea pigs were measured with keratometer and photographed to obtain the horizontal,coronal,and sagittal planes respectively.The corresponding photo pixels-actual length ratio was acquired by a proportional scale.The edge coordinates were identified artificially by ginput function.Circle and conic curve fitting were applied to fit the contour of the eyeball in the sagittal,coronal and horizontal view.The curvature,curvature radius,eccentricity,tilt angle,corneal diameter,and binocular separation angle were calculated according to the geometric principles.Next,the eyeballs were removed,canny edge detection was applied to identify the contour of eyeball in vitro.The results were compared between in vivo and in vitro.RESULTS:Regarding the corneal curvature and curvature radius on the horizontal and sagittal planes,no significant differences were observed among results in vivo,in vitro,and the keratometer.The horizontal and vertical binocular separation angles were 130.6°±6.39°and 129.8°±9.58°respectively.For the corneal curvature radius and eccentricity in vivo,significant differences were observed between horizontal and vertical planes.CONCLUSION:The Graphical interface window of Python makes up the deficiency of edge detection,which requires too much definition in Matlab.There are significant differences between guinea pig and human beings,such as exotropic eye position,oblique oval eyeball,and obvious discrepancy of binoculus.This study helps evaluate objectively the ocular morphological parameters of small experimental animals in emmetropization research. 展开更多
关键词 ocular morphological parameters guinea pig digital measurement PYTHON
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Chaotic Aquila Optimization Algorithm for Solving Phase Equilibrium Problems and Parameter Estimation of Semi-empirical Models
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作者 Oguz Emrah Turgut Mert Sinan Turgut Erhan Kırtepe 《Journal of Bionic Engineering》 SCIE EI CSCD 2024年第1期486-526,共41页
This research study aims to enhance the optimization performance of a newly emerged Aquila Optimization algorithm by incorporating chaotic sequences rather than using uniformly generated Gaussian random numbers.This w... This research study aims to enhance the optimization performance of a newly emerged Aquila Optimization algorithm by incorporating chaotic sequences rather than using uniformly generated Gaussian random numbers.This work employs 25 different chaotic maps under the framework of Aquila Optimizer.It considers the ten best chaotic variants for performance evaluation on multidimensional test functions composed of unimodal and multimodal problems,which have yet to be studied in past literature works.It was found that Ikeda chaotic map enhanced Aquila Optimization algorithm yields the best predictions and becomes the leading method in most of the cases.To test the effectivity of this chaotic variant on real-world optimization problems,it is employed on two constrained engineering design problems,and its effectiveness has been verified.Finally,phase equilibrium and semi-empirical parameter estimation problems have been solved by the proposed method,and respective solutions have been compared with those obtained from state-of-art optimizers.It is observed that CH01 can successfully cope with the restrictive nonlinearities and nonconvexities of parameter estimation and phase equilibrium problems,showing the capabilities of yielding minimum prediction error values of no more than 0.05 compared to the remaining algorithms utilized in the performance benchmarking process. 展开更多
关键词 Aquila optimization algorithm Chaotic maps parameter estimation Phase equilibrium Unconstrained optimization
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Determination of uncertainties of geomechanical parameters of metamorphic rocks using petrographic analyses
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作者 Behzad Dastjerdy Ali Saeidi Shahriyar Heidarzadeh 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第2期345-364,共20页
Geomechanical parameters of intact metamorphic rocks determined from laboratory testing remain highly uncertain because of the great intrinsic variability associated with the degrees of metamorphism.The aim of this pa... Geomechanical parameters of intact metamorphic rocks determined from laboratory testing remain highly uncertain because of the great intrinsic variability associated with the degrees of metamorphism.The aim of this paper is to develop a proper methodology to analyze the uncertainties of geomechanical characteristics by focusing on three domains,i.e.data treatment process,schistosity angle,and mineralogy.First,the variabilities of the geomechanical laboratory data of Westwood Mine(Quebec,Canada)were examined statistically by applying different data treatment techniques,through which the most suitable outlier methods were selected for each parameter using multiple decision-making criteria and engineering judgment.Results indicated that some methods exhibited better performance in identifying the possible outliers,although several others were unsuccessful because of their limitation in large sample size.The well-known boxplot method might not be the best outlier method for most geomechanical parameters because its calculated confidence range was not acceptable according to engineering judgment.However,several approaches,including adjusted boxplot,2MADe,and 2SD,worked very well in the detection of true outliers.Also,the statistical tests indicate that the best-fitting probability distribution function for geomechanical intact parameters might not be the normal distribution,unlike what is assumed in most geomechanical studies.Moreover,the negative effects of schistosity angle on the uniaxial compressive strength(UCS)variabilities were reduced by excluding the samples within a specific angle range where the UCS data present the highest variation.Finally,a petrographic analysis was conducted to assess the associated uncertainties such that a logical link was found between the dispersion and the variabilities of hard and soft minerals. 展开更多
关键词 Intact rock parameters Natural variabilities Outlier detection methods UNCERTAINTIES Westwood mine MINERALOGY
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Clinical nursing value of predictive nursing in reducing complications of pregnant women undergoing short-term massive blood transfusion during cesarean section
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作者 Li Cheng Li-Ping Li +2 位作者 Yuan-Yuan Zhang Fang Deng Ting-Ting Lan 《World Journal of Clinical Cases》 SCIE 2024年第1期51-58,共8页
BACKGROUND Cesarean hemorrhage is one of the serious complications,and short-term massive blood transfusion can easily cause postoperative infection and physical stress response.However,predictive nursing intervention... BACKGROUND Cesarean hemorrhage is one of the serious complications,and short-term massive blood transfusion can easily cause postoperative infection and physical stress response.However,predictive nursing intervention has important clinical significance for it.AIM To explore the effect of predictive nursing intervention on the stress response and complications of women undergoing short-term mass blood transfusion during cesarean section(CS).METHODS A clinical medical record of 100 pregnant women undergoing rapid mass blood transfusion during sections from June 2019 to June 2021.According to the different nursing methods,patients divided into control group(n=50)and observation group(n=50).Among them,the control group implemented routine nursing,and the observation group implemented predictive nursing intervention based on the control group.Moreover,compared the differences in stress res-ponse,complications,and pain scores before and after the nursing of pregnant women undergoing rapid mass blood transfusion during CS.RESULTS The anxiety and depression scores of pregnant women in the two groups were significantly improved after nursing,and the psychological stress response of the observation group was significantly lower than that of the control group(P<0.05).The heart rate and mean arterial pressure(MAP)of the observation group during delivery were lower than those of the control group,and the MAP at the end of delivery was lower than that of the control group(P<0.05).Moreover,different pain scores improved significantly in both groups,with the observation group considerably less than the control group(P<0.05).After nursing,complications such as skin rash,urinary retention,chills,diarrhea,and anaphylactic shock in the observation group were 18%,which significantly higher than in the control group(4%)(P<0.05).CONCLUSION Predictive nursing intervention can effectively relieve the pain,reduce the incidence of complications,improve mood and stress response,and serve as a reference value for the nursing of women undergoing rapid mass transfusion during CS. 展开更多
关键词 Predictive care Rapid mass blood transfusion Cesarean section Stress response COMPLICATIONS
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Drilling-based measuring method for the c-φ parameter of rock and its field application
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作者 Bei Jiang Fenglin Ma +5 位作者 Qi Wang Hongke Gao Dahu Zhai Yusong Deng Chuanjie Xu Liangdi Yao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第1期65-76,共12页
The technology of drilling tests makes it possible to obtain the strength parameter of rock accurately in situ. In this paper, a new rock cutting analysis model that considers the influence of the rock crushing zone(R... The technology of drilling tests makes it possible to obtain the strength parameter of rock accurately in situ. In this paper, a new rock cutting analysis model that considers the influence of the rock crushing zone(RCZ) is built. The formula for an ultimate cutting force is established based on the limit equilibrium principle. The relationship between digital drilling parameters(DDP) and the c-φ parameter(DDP-cφ formula, where c refers to the cohesion and φ refers to the internal friction angle) is derived, and the response of drilling parameters and cutting ratio to the strength parameters is analyzed. The drillingbased measuring method for the c-φ parameter of rock is constructed. The laboratory verification test is then completed, and the difference in results between the drilling test and the compression test is less than 6%. On this basis, in-situ rock drilling tests in a traffic tunnel and a coal mine roadway are carried out, and the strength parameters of the surrounding rock are effectively tested. The average difference ratio of the results is less than 11%, which verifies the effectiveness of the proposed method for obtaining the strength parameters based on digital drilling. This study provides methodological support for field testing of rock strength parameters. 展开更多
关键词 Digital drilling Rock crushing zone c-u parameter Measurement method Field application
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Effects of Fresh Cupressus sempervirens Leaves Infusion on Growth Performance, Intestinal Microbiota and Haemato-Biochemical Parameters in Broilers
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作者 Donfack Mikael Noumbissi Marie Noël Bertine +7 位作者 Ciemeni Michelle Aimee Tindo Tsamene Romario Evelyn Ngwa Bih Djamen Tchantchou Chamberlin Nyembo Kondo Camile Tsafong Jeatsa Franklain Necdem Tsafack Boris Kana Jean Raphaël 《Open Journal of Animal Sciences》 2024年第2期70-87,共18页
The accumulation of growth-promoting antibiotic residues in animal products and the resistance developed by bacteria in poultry farms has led to a search for natural compounds derived from plants. This study was desig... The accumulation of growth-promoting antibiotic residues in animal products and the resistance developed by bacteria in poultry farms has led to a search for natural compounds derived from plants. This study was designed to promote the production performance of broiler chickens using fresh Cupressus sempervirens leaves infusion. Fresh Cupressus sempervirens leaves were harvested, washed, chopped and ground to a paste using a blender and fermented for three days in a closed container at a rate of 500 g/L of water. The solution obtained was filtered and added at the rate of 2, 4, 6, 8 and 10 ml/L of drinking water. The chickens fed on the graded level of the solution were compared to a control ration without an additive and positive control group supplemented with 1 g antibiotic/kg feed. At the finisher phase and throughout the study period, water intake increased significantly (P < 0.05) with increasing levels of infusion. Feed intake decreased significantly (P < 0.05) with 2 and 4 ml of infusion/L drinking water. Live weight and weight gain were significantly (P < 0.05) higher with 6 ml/L, while feed conversion significantly (P < 0.05) decreased with the same treatment compared with the control treatment without additives (T0). Carcass characteristics were not significantly (P > 0.05) affected by the inclusion of Cupressus sempervirens infusion. Haematological parameters significantly (P < 0.05) increase independently of the rate of incorporation of the infusion into the drinking water, with the exception of RBCs, MCHT and PCT. Serum content in total protein, globulins, LDL cholesterol and triglycerides were significantly (P < 0.05) high with 8 and 10 ml Cupressus sempervirens infusion/litre drinking water as compared to all other treatments. AST, ALT, urea, creatine, albumin, total cholesterol and HDL-cholesterol were not significantly affected. The lactic acid bacteria load increased significantly (P E. coli and salmonella counts decreased significantly (P < 0.05) with infusion compared to the control without additive. In conclusion, 6 ml of Cupressus sempervirens infusion can be used as an alternative to antibiotic feed additives to promote growth performance in broilers. 展开更多
关键词 BROILERS Cupressus sempervirens Growth Performance Haemato-Biochemical parameters Intestinal Microbiota
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