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Influence of Omega 3 Fatty Acid Supplementation on Phase Angle Values of People Living with HIV/AIDS with Lipodystrophy Secondary to Antiretroviral Therapy: A Randomized Clinical Trial
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作者 Thalita Bandeira Dantas Alline Peralta Castro +1 位作者 Fernando de Souza Flexa Ribeiro Filho Rosana Maria Feio Libonati 《Food and Nutrition Sciences》 CAS 2024年第1期58-70,共13页
Objective: The measurement of phase angles is an important monitoring parameter and supplementation with omega-3 could promote benefits by modulating the electrical potential of membranes and increasing body cell mass... Objective: The measurement of phase angles is an important monitoring parameter and supplementation with omega-3 could promote benefits by modulating the electrical potential of membranes and increasing body cell mass. This study aimed to evaluate the effectiveness of omega-3 fatty acid supplementation on the phase angle of people living with HIV/AIDS. Methods: In this study, 63 individuals of all genders who were undergoing outpatient follow-up and showed lipodystrophy due to highly active antiretroviral therapy were analyzed. Our sample consisted of two groups, one that received supplementation containing 2550 mg of omega-3/day (1080 mg of eicosapentaenoic acid and 720 mg of docosahexaenoic acid) for three months (n = 32) and another that underwent nutrition guidance (n = 31). Phase angle and body cell mass were assessed for both groups and compared at the beginning of research (T0) and after our intervention (T1) for each group separately. Results: Phase angle averaged 6.45° ± 1.06 SD. The comparison between T0 and T1 showed a significant increase in phase angle and body cell mass, whereas the guidance group showed a decrease in body cell mass at T1 in relation to T0, with a significant p-value. Variance in phase angle between moments showed significant values between T0 and T1 in the supplementation group for all genders. Conclusion: Omega-3 positively modulated patients phase angle and body cell mass, but we emphasize the need for other studies that can solidify knowledge about supplementation dosage and intervention time. 展开更多
关键词 HIV LIPODYSTROPHY Omega-3 Phase angle
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Visualizing the Local Twist Angle Variation within and between Domains of Twisted Bilayer Graphene
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作者 户佳玮 朱诗雨 +7 位作者 胡倩颖 王云昊 申承民 杨海涛 竺晓山 郇庆 许杨 高鸿钧 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第3期146-151,共6页
Moirésuperlattices in twisted two-dimensional materials have emerged as ideal platforms for engineering quantum phenomena,which are highly sensitive to twist angles,including both the global value and the spatial... Moirésuperlattices in twisted two-dimensional materials have emerged as ideal platforms for engineering quantum phenomena,which are highly sensitive to twist angles,including both the global value and the spatial inhomogeneity.However,only a few methods provide spatial-resolved information for characterizing local twist angle distribution. 展开更多
关键词 angle TWIST TWIST
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In situ calibrated angle between the quantization axis and the propagating direction of the light field for trapping neutral atoms
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作者 郭瑞军 何晓东 +7 位作者 盛诚 王坤鹏 许鹏 刘敏 王谨 孙晓红 曾勇 詹明生 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期318-323,共6页
The recently developed magic-intensity trapping technique of neutral atoms efficiently mitigates the detrimental effect of light shifts on atomic qubits and substantially enhances the coherence time. This technique re... The recently developed magic-intensity trapping technique of neutral atoms efficiently mitigates the detrimental effect of light shifts on atomic qubits and substantially enhances the coherence time. This technique relies on applying a bias magnetic field precisely parallel to the wave vector of a circularly polarized trapping laser field. However, due to the presence of the vector light shift experienced by the trapped atoms, it is challenging to precisely define a parallel magnetic field, especially at a low bias magnetic field strength, for the magic-intensity trapping of85Rb qubits. In this work, we present a method to calibrate the angle between the bias magnetic field and the trapping laser field with the compensating magnetic fields in the other two directions orthogonal to the bias magnetic field direction. Experimentally, with a constantdepth trap and a fixed bias magnetic field, we measure the respective resonant frequencies of the atomic qubits in a linearly polarized trap and a circularly polarized one via the conventional microwave Rabi spectra with different compensating magnetic fields and obtain the corresponding total magnetic fields via the respective resonant frequencies using the Breit–Rabi formula. With known total magnetic fields, the angle is a function of the other two compensating magnetic fields.Finally, the projection value of the angle on either of the directions orthogonal to the bias magnetic field direction can be reduced to 0(4)° by applying specific compensating magnetic fields. The measurement error is mainly attributed to the fluctuation of atomic temperature. Moreover, it also demonstrates that, even for a small angle, the effect is strong enough to cause large decoherence of Rabi oscillation in a magic-intensity trap. Although the compensation method demonstrated here is explored for the magic-intensity trapping technique, it can be applied to a variety of similar precision measurements with trapped neutral atoms. 展开更多
关键词 quantization axis trapping laser angle compensating magnetic fields
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On the effect of pitch and yaw angles in oblique impacts of smallcaliber projectiles
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作者 Teresa Fras 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期73-94,共22页
A terminal ballistic analysis of the effects of 7.62 mm × 51 AP P80 rounds on inclined high-strength armor steel plates is the focus of the presented study.The findings of an instrumented ballistic testing combin... A terminal ballistic analysis of the effects of 7.62 mm × 51 AP P80 rounds on inclined high-strength armor steel plates is the focus of the presented study.The findings of an instrumented ballistic testing combined with 3D advanced numerical simulations performed using the IMPETUS Afea? software yielded the conclusions.The experimental verification proved that slight differences in the pitch-andyaw angles of a projectile upon an impact caused different damage types to the projectile’s core.The residual velocities predicted numerically were close to the experimental values and the calculated core deviations were in satisfactory agreement with the experimental results.An extended matrix of the core deviation angles with combinations of pitch-and-yaw upon impact angles was subsequently built on the basis of the numerical study.The presented experimental and numerical investigation examined thoroughly the influence of the initial pitch and yaw angles on the after-perforation projectile’s performance. 展开更多
关键词 Ballistic impact Small-caliber projectile Pitch and yaw impact angles SHADOWGRAPHY IMPETUS Afea Numerical simulations
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The Youth’s View of Marriage in Chinese Mainstream Media Discourse-A Corpus-assisted Three-dimensional Discourse Analysis
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作者 DING Shu-li LIN Ying 《Journal of Literature and Art Studies》 2024年第4期284-289,共6页
The rising of aging and the declining of birth rates have forced the public to focus on the youth’s view on marriage.Based on critical discourse analysis and combined with Fairclough’s three-dimensional discourse an... The rising of aging and the declining of birth rates have forced the public to focus on the youth’s view on marriage.Based on critical discourse analysis and combined with Fairclough’s three-dimensional discourse analysis model,this paper builds a“Chinese media News Report Corpus on the topic of‘marriage’”whose news are collected from China Daily.It is found that the discourses are neutral and objective with regard to the advantages and disadvantages of marriage,but in general,it is still a traditional view of marriage that is inevitable and closely related to fertility.Although this is controlled by the policies and the social reasons including declining fertility rate,it deviates from the current view of the youth towards marriage,resulting in many serious consequences such as young people’s rejection.In addition,this research found that male and female have great differences in their views on marriage,and men’s resistance to marriage is far greater than that of women,which is departure from the public’s cognition.The reasons behind this need to be explored in order to solve the marriage and love problems of young people in today’s era and realize the healthy development of young marriage. 展开更多
关键词 CORPORA Three-dimensional discourse analysis the youth’view of marriage
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Cost of Medical Treatment for Primary Open-Angle Glaucoma in Relation to Patients’ Income and Its Impact on the Prognosis of the Disease, in Bouaké University Hospital
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作者 Yves Ouattara Liliane Ella Godé +5 位作者 Zana Diabaté Franck Hermann Koffi Mamadou Korka Diallo Philippe Emile France Koffi Bilé Diomandé François Gossé Ibrahim Abib Diomandé 《Open Journal of Ophthalmology》 2024年第1期8-17,共10页
Introduction: Medical treatment for POAG is continuous and lifelong treatment. The aim of this study was to evaluate the relationship between the cost of this treatment and patients’ income and the impact of this rel... Introduction: Medical treatment for POAG is continuous and lifelong treatment. The aim of this study was to evaluate the relationship between the cost of this treatment and patients’ income and the impact of this relationship on treatment compliance. Materials and Methods: Prospective cross-sectional study with a descriptive aim covering sociodemographic data, average incomes, and direct and indirect costs of treatment of 57 patients followed for POAG during the period from January 1, 2012, to December 31, 2016 (5 years). Results: The patients were aged 25 to 77 years (mean = 54.4 years) with a male predominance (sex ratio = 1.5). Retirees were the most represented (26.32%), followed by workers in the informal sector (14.04%) and housewives (12.28%). Patients who had an annual income less than or equal to 900,000 CFA francs (€1370.83) per year represented 56.14% and those who did not have health coverage represented 57.89%. The treatment was monotherapy (64.91%), dual therapy (31.58%) or triple therapy (3.05%) and the average ratio of “annual cost of treatment to annual income” was 0.56 with for maximum 2.23 and 0.02 as minimum. Patients who considered the cost of treatment unbearable for their income represented 78.95%. Conclusion: Prevention of blindness due to glaucoma requires early detection but also the establishment of health coverage mechanisms to improve compliance with medical treatment. In addition, consideration should be given to the development of glaucoma surgery in our country, the indication of which could be the first intention in certain patients, considering for those patients, the geographical and financial accessibility of medical treatment. . 展开更多
关键词 Primary Open-angle Glaucoma Treatment Cost Medical Treatment INCOME BLINDNESS
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Epidemiological, Clinical, Therapeutic and Evolutive Profile of Primary Open-Angle Glaucoma in a Cameroonian Population
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作者 Christelle Domngang Fabiola Makamwe Tagne +3 位作者 Leonard Tedong Chantal Ngoune Nanfack Caroline Mvilongo Giles Kagmeni 《Open Journal of Ophthalmology》 2024年第2期93-102,共10页
Background: Sub-Saharan Africa has the highest prevalence of primary open-angle glaucoma (POAG), at 4.2%. The efficacy of medical treatment has been demonstrated and remains one of the treatments of choice for POAG. H... Background: Sub-Saharan Africa has the highest prevalence of primary open-angle glaucoma (POAG), at 4.2%. The efficacy of medical treatment has been demonstrated and remains one of the treatments of choice for POAG. However, in sub-Saharan Africa, its effectiveness has many challenges, due to multiple factors, including cost and access to care. Thus, the present study aimed to determine the epidemiological, clinical, therapeutic and evolutive profile of primary open-angle glaucoma patients. Methodology: A descriptive cross-sectional study was carried out in two hospitals in western Cameroon. Epidemiological, clinical, therapeutic, and evolutionary data on intraocular pressure at one year after medical treatment were analyzed. SPSS version 23 software was used for statistical analysis, with a significant p-value set at 5%. Results: A total of 201 patients with POAG were included in the study. The population comprised 100 men and 101 women, with a mean age of 54 ± 12 years. At diagnosis, the mean intraocular pressure was 23.9 ± 8.70 mmHg for the right eye and 25.5 ± 9.57 mmHg for the left eye. The mean cup/disc ratio was 0.64 ± 0.2 [0.2-1] and 0.67 ± 0.19 [02-1] in the right and left eyes, respectively. Monotherapy was the most prescribed treatment [59.2%]. After one year of treatment, intraocular pressure was reduced by 15.5% with beta-blockers, 23.66% with prostaglandins, 19.11% with carbonic anhydrase inhibitors, 35, 92% with beta-blockers and carbonic anhydrase inhibitors, 25.92% with beta-blockers and prostaglandins, 48.03% with carbonic anhydrase inhibitors and prostaglandin agonists, and 38.77% with triple therapy. Taking glaucoma severity into account, a significant reduction in intraocular pressure at one year was observed in all participants [p 0.05]. However, the target pressure was obtained in 47%, 20% and 14% of eyes suffering of mild, moderate, and severe grade of POAG respectively. Conclusion: In the present study, there was a significant reduction in intraocular pressure after one year of medical treatment. However, the reduction in intraocular pressure does not allow the target pressure to be reached in severe forms. Thus, alternatives to the medical treatment of POAG should be discussed early in the present context. . 展开更多
关键词 Primary Open-angle Glaucoma Medical Treatment Intraocular Pressure Target Intraocular Pressure
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The Regularity of Solutions to Mixed Boundary Value Problems of Second-Order Elliptic Equations with Small Angles
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作者 Mingyu Wu 《Journal of Applied Mathematics and Physics》 2024年第4期1043-1049,共7页
This paper considers the regularity of solutions to mixed boundary value problems in small-angle regions for elliptic equations. By constructing a specific barrier function, we proved that under the assumption of suff... This paper considers the regularity of solutions to mixed boundary value problems in small-angle regions for elliptic equations. By constructing a specific barrier function, we proved that under the assumption of sufficient regularity of boundary conditions and coefficients, as long as the angle is sufficiently small, the regularity of the solution to the mixed boundary value problem of the second-order elliptic equation can reach any order. 展开更多
关键词 Mixed Boundary Value Problems for Elliptic Equations Small-angle Boundary Value Problems Regularity of Solutions to Elliptic Equations
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The anisotropy of suprathermal electrons in the Martian ionosphere
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作者 YuTian Cao Jun Cui +3 位作者 XiaoShu Wu WenJun Liang RuiQi Fu HaoYu Lu 《Earth and Planetary Physics》 EI CAS CSCD 2024年第3期459-471,共13页
Suprathermal electrons are an important population of the Martian ionosphere, either produced by photoionization of atmospheric neutrals or supplied from the Solar Wind (SW). This study is dedicated to an in-depth inv... Suprathermal electrons are an important population of the Martian ionosphere, either produced by photoionization of atmospheric neutrals or supplied from the Solar Wind (SW). This study is dedicated to an in-depth investigation of the pitch angle distribution of suprathermal electrons at two representative energies, 19−55 eV and 124−356 eV, using the extensive measurements made by the Solar Wind Electron Analyzer on board the Mars Atmosphere and Volatile Evolution. Throughout the study, we focus on the overall degree of anisotropy, defined as the standard deviation of suprathermal electron intensity among different directions which is normalized by the mean omni-directional intensity. The available data reveal the following characteristics: (1) In general, low energy electrons are more isotropic than high energy electrons, and dayside electrons are more isotropic than nightside electrons;(2) On the dayside, the anisotropy increases with increasing altitude at low energies but remains roughly constant at high energies, whereas on the nightside, the anisotropy decreases with increasing altitude at all energies;(3) Electrons tend to be more isotropic in strongly magnetized regions than in weakly magnetized regions, especially on the nightside. These observations indicate that the anisotropy is a useful diagnostic of suprathermal electron transport, for which the conversion between the parallel and perpendicular momenta as required by the conservation of the first adiabatic invariant, along with the atmospheric absorption at low altitudes, are two crucial factors modulating the observed variation of the anisotropy. Our analysis also highlights the different roles on the observed anisotropy exerted by suprathermal electrons of different origins. 展开更多
关键词 MARS IONOSPHERE suprathermal electron pitch angle distribution
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Influence of Flap Parameters on the Aerodynamic Performance of a Wind-Turbine Airfoil
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作者 Yuanjun Dai Jingan Cui +2 位作者 Baohua Li Cong Wang Kunju Shi 《Fluid Dynamics & Materials Processing》 EI 2024年第4期771-786,共16页
A numerical method has been used to analyze the flow field related to a NACA 0015 airfoil with and without a flap and assess the influence of the flap height and angle on the surface pressure coefficient,lift coeffici... A numerical method has been used to analyze the flow field related to a NACA 0015 airfoil with and without a flap and assess the influence of the flap height and angle on the surface pressure coefficient,lift coefficient,and drag coefficient.The numerical results demonstrate that the flap can effectively improve the lift coefficient of the airfoil;however,at small attack angles,its influence is significantly reduced.When the angle of attack exceeds the critical stall angle and the flap height is 1.5%of the chord length,the influence of the flap becomes very evident.As the flap height increases,the starting point of the separation vortex gradually moves forward and generates a larger wake vortex.Optimal aerodynamic characteristics are obtained for 1.5%(of the chord length)flap height and a 45°flap angle;in this case,the separation vortex is effectively reduced. 展开更多
关键词 AIRFOIL flap height flap angle lift-drag ratio aerodynamic characteristics
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An approach for determination of lateral limit angle in kinematic planar sliding analysis for rock slopes
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作者 Xiaojuan Yang Jie Hu +1 位作者 Honglei Sun Jun Zheng 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第4期1305-1314,共10页
Planar sliding is one of the frequently observed types of failure in rock slopes.Kinematic analysis is a classic and widely used method to examine the potential failure modes in rock masses.The accuracy of planar slid... Planar sliding is one of the frequently observed types of failure in rock slopes.Kinematic analysis is a classic and widely used method to examine the potential failure modes in rock masses.The accuracy of planar sliding kinematic analysis is significantly influenced by the value assigned to the lateral limit angleγlim.However,the assignment ofγlim is currently used generally based on an empirical criterion.This study aims to propose an approach for determining the value ofγlim in deterministic and probabilistic kinematic planar sliding analysis.A new perspective is presented to reveal thatγlim essentially influences the probability of forming a potential planar sliding block.The procedure to calculate this probability is introduced using the block theory method.It is found that the probability is correlated with the number of discontinuity sets presented in rock masses.Thus,different values ofγlim for rock masses with different sets of discontinuities are recommended in both probabilistic and deterministic planar sliding kinematic analyses;whereas a fixed value ofγlim is commonly assigned to different types of rock masses in traditional method.Finally,an engineering case was used to compare the proposed and traditional kinematic analysis methods.The error rates of the traditional method vary from 45%to 119%,while that of the proposed method ranges between 1%and 17%.Therefore,it is likely that the proposed method is superior to the traditional one. 展开更多
关键词 Kinematic analysis Block theory Planar sliding Lateral limit angle Rock slope
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Characteristics of the electromagnetic wave propagation in magnetized plasma sheath and practical method for blackout mitigation
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作者 吴翔 张珈珲 +1 位作者 董果香 石磊 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期489-499,共11页
“Magnetic window”is considered as an effective method to solve the communication blackout issue.COMSOL software package based on the finite element method is utilized to simulate the propagation of right-handed circ... “Magnetic window”is considered as an effective method to solve the communication blackout issue.COMSOL software package based on the finite element method is utilized to simulate the propagation of right-handed circularly polarized wave in the magnetized plasma sheath.We assume a double Gaussian model of electron density and an exponential attenuation model of magnetic field.The propagation characteristics of right-handed circularly polarized wave are analyzed by the observation of the reflected,transmitted and loss coefficient.The numerical results show that the propagation of right-handed circularly polarized wave in the magnetized plasma sheath varies for different incident angles,collision frequencies,non-uniform magnetic fields and non-uniform plasma densities.We notice that reducing the wave frequency can meet the propagation conditions of whistle mode in the weak magnetized plasma sheath.And the transmittance of whistle mode is less affected by the variation of the electron density and the collision frequency.It can be used as a communication window. 展开更多
关键词 magnetized plasma sheath communication blackout finite element incident angle whistler wave
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Damage Characteristics Analysis and Fractal Study of Shale With Prefabricated Fractures under Thermal-mechanical Coupling
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作者 张辉 邬忠虎 +3 位作者 SONG Huailei WANG Wentao TANG Motian CUI Hengtao 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第3期570-586,共17页
To study the damage and failure of shale with different fracture inclination angles under uniaxial compression loading,in this work,RFPA2D-Thermal,a two-dimensional real failure process analysis software,was used for ... To study the damage and failure of shale with different fracture inclination angles under uniaxial compression loading,in this work,RFPA2D-Thermal,a two-dimensional real failure process analysis software,was used for numerical simulation.Numerical simulation results show that quartz in shale mainly affects the tensile and compressive strength of shale by increasing rock brittleness.The coupling of temperature and pressure will cause lateral and volume destruction of shale,which enables the shale body to be more easily broken.Fracture inclination is the key factor affecting shale damage patterns.The failure mode of shale with low-and high-angle fractures is mainly shear failure,and the compressive strength does not vary with crack inclination.The damage mode of obliquely intersecting fractured shale is slip damage along the fracture face,the compressive strength decreases and then increases with the fracture inclination,and a minimum value exists.The acoustic emission simulation results of the damage process effectively reflect the accumulated internal damage and macroscopic crack appearance until fracture instability when the prefabricated fractured shale is subjected to uniaxial compressive loading.The crack inclinations of 0°and 120℃ corresponds to the most complex"N"shape damage mode.The crack inclinations of 30°and 60°,and the damage mode is an inverted"λ"shape. 展开更多
关键词 SHALE temperature and pressure numerical simulation fracture dip angle fractal dimension
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Efficacy and safety of Usights UC100 illuminated microcatheter in microcatheter-assisted trabeculotomy
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作者 Shuo Yu Ke Xu Chun Zhang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第2期272-277,共6页
AIM:To evaluate the efficacy and safety of Usights UC100 illuminated microcatheter in microcatheter-assisted trabeculotomy(MAT).METHODS:Totally 10 eyes of 10 patients with primary open angle glaucoma(POAG)who underwen... AIM:To evaluate the efficacy and safety of Usights UC100 illuminated microcatheter in microcatheter-assisted trabeculotomy(MAT).METHODS:Totally 10 eyes of 10 patients with primary open angle glaucoma(POAG)who underwent MAT facilitated by Usights UC100(5 eyes)or iTrack(5 eyes)were reviewed.The success of this surgery was defined as intraocular pressure(IOP)<22 mm Hg with>30%reduction,without oral glaucoma medications,or additional glaucoma surgery.RESULTS:The mean pre-operative IOP was 25.38±10.22 mm Hg in the Usights UC100 group and 19.98±3.87 mm Hg in the iTrack group.MAT was achieved in all eyes in both groups.The success rates for the Usights UC100 group and iTrack groups were in all and 4 eyes,respectively.Both microcatheters produced a statistically significant reduction in IOP,and eyes using Usights UC100 achieved a lower IOP than the iTrack group at 3mo followup(12.58±1.52 and 14.84±1.89 mm Hg,respectively),but no statistical significance was there.No severe side effects were observed in either group.CONCLUSION:MAT using Usights UC100 or iTrack both achieve significant pressure reduction in cases of POAG,and Usights UC100 is as safe as iTrack. 展开更多
关键词 illuminated microcatheter microcatheterassisted trabeculotomy primary open angle glaucoma
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Effect of Nozzle Inclination Angle on Fuel-Air Mixing and Combustion in a Heavy Fuel Engine
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作者 Zhigang Wang Bin Zheng +4 位作者 Peidong Zhao Baoli Wang Fanyan Meng Wenke Xu Jian Meng 《Fluid Dynamics & Materials Processing》 EI 2024年第2期365-382,共18页
Heavy-fuel engines are widely used in UAVs(Unmanned Autonomous Vehicles)because of their reliability and high-power density.In this study,a combustion model for an in-cylinder direct injection engine has been imple-me... Heavy-fuel engines are widely used in UAVs(Unmanned Autonomous Vehicles)because of their reliability and high-power density.In this study,a combustion model for an in-cylinder direct injection engine has been imple-mented using the AVL FIRE software.The effects of the angle of nozzle inclination on fuel evaporation,mixture distribution,and combustion in the engine cylinder have been systematically studied at 5500 r/min and consider-ing full load cruise conditions.According to the results,as the angle of nozzle inclination increases,the maximum combustion explosion pressure in the cylinderfirst increases and then it decreases.When the angle of nozzle incli-nation is less than 45°,the quality of the mixture in the cylinder and the combustion performance can be improved by increasing the angle.When the angle of nozzle inclination is greater than 45°,however,the mixture unevenness increases slightly with the angle,leading to a deterioration of the combustion performances.When the angle of nozzle inclination is between 35°and 55°,the overall combustion performance of the engine is rela-tively good.When the angle of nozzle inclination is 45°,the combustion chamber’s geometry and the cylinder’s airflow are well matched with the fuel spray,and the mixture quality is the best.Compared with 25°,the peak heat release rate increases by 20%,and the maximum combustion burst pressure increases by 5.5%. 展开更多
关键词 Aviation heavy fuel piston engine nozzle inclination angle COMBUSTION fuel-air mixing
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Exploring the Path of Shantytown Renewal Based on the Theory of Environment-behavior Studies: A Case Study of the Northwest Area of Saihantala in Baotou City
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作者 ZHANG Miao TIAN Jiaqi GONG Rui 《Journal of Landscape Research》 2024年第2期61-65,68,共6页
The application of environment-behavior studies plays an important role in studying the renewal of shantytowns.One of the most humane ways of renewal is designing and constructing the necessary urban spatial environme... The application of environment-behavior studies plays an important role in studying the renewal of shantytowns.One of the most humane ways of renewal is designing and constructing the necessary urban spatial environment from the perspective of human daily behavior.Most of the shantytown renovation projects currently carried out in China are mainly focused on demolition and reconstruction,which not only incurs high costs but also damages the original social structure and economic model.During the process of shantytown renewal,it should improve the urban landscape,living environment,and life quality of residents,and ensure the daily life of shantytown residents without increasing their economic burden,and preserve the traces of urban development.In order to achieve this goal,it should explore the renewal strategies of shantytowns from the perspective of environment-behavior studies through behavior maps,on-site research,and literature review.Updating and design from a human perspective often achieve faster and better development;the renewal of shantytowns should be a bottom-up approach and start from a grassroots perspective,completing the renovation design through the composition of the population and behavioral patterns. 展开更多
关键词 Environment-behavior studies Shantytown renewal Economic type Bottom view BOTTOM-UP
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Functional Dependence of IM and HV Angle in Hallux Valgus Deformity before and after Operative
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作者 Nenad Stojanović Mirko Sovilj Vesna Ivanišević 《Journal of Applied Mathematics and Physics》 2024年第5期1626-1646,共21页
Hallux valgus is a relatively common and multifaceted complex deformity of the front part of the foot. It is the result of multiple effects of innate (endogenous) and exogenous etiological factors with different degre... Hallux valgus is a relatively common and multifaceted complex deformity of the front part of the foot. It is the result of multiple effects of innate (endogenous) and exogenous etiological factors with different degrees of influence. The degree of hallux valgus deformity is usually assessed by radiological values of hallux valgus (HV) and intermetatarsal (IM) angles. The aim of the paper is to justify the definition of hallux valgus deformity as a function of one angle, (HVA or IMA), and then to determine the functional connection and the most suitable function equalizing the values of the angles IMA and HVA. As hallux valgus is a double angulation deformity, the analytically determined connection between the HVA and IMA angles reduces the study of the deformity to the study of function with one argument, and makes the analysis of deformity changes before and after operative treatment simpler. For the determined connections between the angles, the values of linear proportionality coefficients and regression coefficients of corresponding linear functions of analytical equalization of the value of the IM angle and the degree of deformity for a given value of the HV angle were experimentally determined. The obtained results were checked on a sample of 396 operatively treated hallux valgus deformities. The presented analytical approach and the obtained functional links of IMA and HVA enable quantitative observation of the change in the degree of deformity based on the radiologically determined value of these angles, and the established nonlinear function will be useful for evaluating the expected value of the IM angle and the degree of deformity based only on the measured value of the HV angle. . 展开更多
关键词 Functional Connection of Deformity angles Analytical Equalization of IM angle Values Hallux Valgus Intermetatarsal angle Correction of Deformity
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An improved positioning model of deep-seafloor datum point at large incidence angle
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作者 Qianqian LI Shoulian CAO +2 位作者 Fanlin YANG Yu LUO Qian TONG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第1期90-100,共11页
The inhomogeneous sound speed in seawater causes refraction of sound waves,and the elimination of the refraction effect is essential to the accuracy of underwater acoustic positioning.The raytracing method is an indis... The inhomogeneous sound speed in seawater causes refraction of sound waves,and the elimination of the refraction effect is essential to the accuracy of underwater acoustic positioning.The raytracing method is an indispensable tool for effectively handling problems.However,this method has a conflict between localization accuracy and computational quantity.The equivalent sound speed profile(ESSP)method uses a simple sound speed profile(SSP)instead of the actual complex SSP,which can improve positioning precision but with residual error.The residual error is especially non-negligible in deep water and at large beam incidence angles.By analyzing the residual error of the ESSP method through a simulation,an empirical formula of error is presented.The data collected in the sailing circle mode(large incidence angle)of the South China Sea are used for verification.The experiments show that compared to the ESSP method,the improved algorithm has higher positioning precision and is more efficient than the ray-tracing method. 展开更多
关键词 underwater acoustic positioning seafloor datum points large incident angle equivalent sound speed profile(ESSP) deep water
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An improved algorithm based on equivalent sound velocity profile method at large incident angle
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作者 Qianqian Li Qian Tong +3 位作者 Fanlin Yang Qi Li Zhihao Juan Yu Luo 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第2期161-167,共7页
With the development of ultra-wide coverage technology,multibeam echo-sounder(MBES)system has put forward higher requirements for localization accuracy and computational efficiency of ray tracing method.The classical ... With the development of ultra-wide coverage technology,multibeam echo-sounder(MBES)system has put forward higher requirements for localization accuracy and computational efficiency of ray tracing method.The classical equivalent sound speed profile(ESSP)method replaces the measured sound velocity profile(SVP)with a simple constant gradient SVP,reducing the computational workload of beam positioning.However,in deep-sea environment,the depth measurement error of this method rapidly increases from the central beam to the edge beam.By analyzing the positioning error of the ESSP method at edge beam,it is discovered that the positioning error increases monotonically with the incident angle,and the relationship between them could be expressed by polynomial function.Therefore,an error correction algorithm based on polynomial fitting is obtained.The simulation experiment conducted on an inclined seafloor shows that the proposed algorithm exhibits comparable efficiency to the original ESSP method,while significantly improving bathymetry accuracy by nearly eight times in the edge beam. 展开更多
关键词 equivalent sound speed profile ray tracing method large incident angle edge beam deep sea error correction multibeam echo-sounder system
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Investigating the Creation of Cultural Atmospheres in Physical Bookstores Within the Context of Scene-Based Consumption:A Perspective Based on the Ways of Seeing
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作者 Chai Dongdong He Jiani 《Contemporary Social Sciences》 2024年第3期92-105,共14页
In an era of scene-based consumption,the essence of operating a bookstore lies in accepting and enabling the bookstore to play its role as a cultural medium for browsing and appreciating books,which in turn fosters th... In an era of scene-based consumption,the essence of operating a bookstore lies in accepting and enabling the bookstore to play its role as a cultural medium for browsing and appreciating books,which in turn fosters the development of a distinctive bookstore culture.This new type of consumption context has led to an evolution in the book-reading culture in physical bookstores that is characterized by a shift from a paradigm of passive reading to one where the emphasis is on interactive viewing.This transition has laid the foundation for the creation of cultural atmospheres in bookstores,and it highlights the visual interactions that now exist between readers and books as well as with other related cultural industries.The dominant and fundamental logic behind this process is symbiosis,experience,aesthetics,immersion,and creativity.However,when a form of culture that focuses on consumption-oriented browsing begins to overshadow knowledge acquisition during the process of book reading,the cultural essence of bookstores is likely to be diminished.Therefore,the cultural essence within the scene-based consumption context should be enhanced by creating innovative viewing activities that showcase the cultural and emotional implications inherent in the scene itself,and thus help to align the identity of the bookstore with its in-situ cultural space. 展开更多
关键词 physical bookstores bookstore culture scene-based viewing scene-based consumption the creation of cultural atmospheres
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