COMPLETE KAHLER METRICS WITH POSITIVE HOLOMORPHIC SECTIONAL CURVATURES ON CERTAIN LINE BUNDLES(RELATED TO A COHOMOGENEITY ONE POINT OF VIEW ON A YAU CONJECTURE)

In this article,we study Kahler metrics on a certain line bundle over some compact Kahler manifolds to find complete Kahler metrics with positive holomorphic sectional(or bisectional)curvatures.Thus,we apply a strategy to a famous Yau conjecture with a co-homogeneity one geometry.

Rapid progress of an iris metastasis from esophageal cancer:a case report and review of literature

This case report details a rare instance of rapid iris metastasis from esophageal cancer in a 59-year-old man.A literature review was conducted to explore recent advances in detecting,diagnosing,and treating intraocular metastatic malignancies.Positron emission tomographycomputed tomography played a crucial role in identifying primary sites and systemic metastases.Local treatment combined with systemic therapy effectively reduced tumor size,preserved useful vision,and improved the patient’s survival rate.A comparison was made of the characteristics of iris metastases from esophageal cancer and lung cancer,including age,gender,tumor characteristics,and treatment.The challenges associated with diagnosis and treatment are discussed,highlighting the implications for clinical practice.

Distribution and correlation of refractive parameters in children with different corneal curvatures in southeast China

AIM:To analyze the distribution of refractive status in school-age children with different corneal curvatures(CC)and the correlation between CC and refractive status.METHODS:A total of 2214 school-aged children of grade 4 in Hangzhou who were screened for school myopia were included.Uncorrected distance visual acuity(UCDVA),non-cycloplegic refraction,axial length(AL),horizontal and vertical corneal curvature(K1,K2)were measured and spherical equivalent(SE),corneal curvature radius(CCR)and axial length/corneal radius of curvature ratio(AL/CR)were calculated.UCDVA<5.0 and SE≤-0.50 D were classified as school-screening myopia.According to the different CCRs,the patients were divided into the lower corneal curvature(LCC)group(CCR≥7.92)and the higher corneal curvature(HCC)group(CCR<7.92).Each group was further divided into the normal AL subgroup and the long AL subgroup.The refractive parameters were compared to identify any differences between the two groups.RESULTS:Both SE and AL were greater in the LCC group(P=0.013,P<0.001).The prevalence of myopia was 38% in the LCC group and 44% in the HCC group(P<0.001).The proportion of children without screening myopia was higher in the LCC group(62%)than in the HCC group(56%).Among these children without screening myopia,the proportion of long AL in the LCC group(24%)was significantly higher than that in the HCC group(0.012%;P<0.001).The change of SE in the LCC group was less affected by the increase of AL than that in the HCC group.CONCLUSION:School-aged children in the LCC group have a lower incidence of screening myopia and longer AL.Low CC can mask SE reduction and AL growth to some extent,and the change of AL growth change more in children with low CC than high CC.Before the onset of myopia,its growth rate is even faster than that after the onset of myopia.

THE LOGARITHMIC SOBOLEV INEQUALITY FOR A SUBMANIFOLD IN MANIFOLDS WITH ASYMPTOTICALLY NONNEGATIVE SECTIONAL CURVATURE

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.

ISO 22163:2023新版标准变化点解析与IRIS认证的实施

ISO22163:2023是轨道交通行业领域新发布的质量管理体系国际标准,本文从标准的范围、术语定义、过程方法和重要内容变化点、其他优化完善等方面分析了国际标准ISO22163:2023与其升级前的版本ISO/TS22163:2017的主要内容差异,包括产品安全、社会责任、能力要求、外部供方评估、RAMS/LCC、FAI、软件工具以及其他优化完善等,总结了IRIS认证变化点,主要涵盖评估过程、认证实施和认证绩效等级的变化,并提出了IRIS认证标准转版的时间节点、风险评估和体系文件策划的相关建议,以期为更好理解和实施该标准提供借鉴。

IRIS国际铁路行业标准及认证趋势分析

从IRIS定义、产生背景、实施IRIS对企业的益处、认证流程、认证机构等方面对IRIS进行简要介绍,并对IRIS官方数据库信息进行统计分析后概述IRIS的现状,并对未来IRIS认证进行了趋势分析。

基于IRIS和Python平台的人脸识别技术研究

IRIS数据平台以高效的性能进行实时获取、处理数据而广泛得到应用,Python是一种功能强大、简单易学的编程语言,其具有简洁的语法和丰富的第三方库支持,特别适合用于开发人工智能应用程序。文章详细介绍了IRIS与Python数据交互的方法,并且以人脸识别为例,在Python平台和IRIS平台实现了基于OpenCV的局部二进制模式直方图(LocalBinaryPatternHistogram,LBPH)算法,对比分析了LBPH算法在不同平台上的执行效率,为人脸识别技术的研究提供了更多理论依据。

RANDERS SPACES WITH SCALAR FLAG CURVATURE

Let(M, F) be an n-dimensional Randers space with scalar flag curvature. In this paper, we will introduce the definition of a weak Einstein manifold. We can prove that if(M, F) is a weak Einstein manifold, then the flag curvature is constant.

IRIS模式促进STEAM教学区域均衡发展

当今世界对创新能力的呼唤为STEAM教育提供了时代土壤。当下,农村学校由于受师资、实践装备数量与质量的困扰,造成STEAM教学区域均衡发展困难。在农村信息科技教学中,我们可以尝试采用IRIS模式,促进STEAM教学区域均衡发展。

Autonomous and Mobile Prototype of Curvature Sensor with Remote Reliable Communication of Spectral Curvature

Through the creation and construction of a curvature sensor of accelerometer type, using the spectral curvature concept or curvature energy that measures curvature in Volts/m3, an autonomous and mobile censorship of curvature sensing with reliable data transmission/reception in real time and remote position is designed and constructed considering the spectra of curvature of the measured curvature energy during the advance of the prototype as the normed measure by with β , a constant rationalized parameter according with the required advance of the mobile device in the control scale of their velocity. Likewise, the sensed curvature data are digitalized through wireless interconnectivity using a HC-05 Module with a programmable device that includes logic blocks whose interconnection and functionality can be configured according to the sensor measure in situs. Also an application is planted to the obtaining of an energy plus due to the curvature that could be used in the displacement of a vehicle.

从“BLACK IRISH”商标案看欧盟与中国对于商标绝对性驳回理由审查的异同

欧盟“BLACK IRISH”商标申请案情介绍2020年1月29日,申请人LOTION LLC向欧盟知识产权局申请注册了“BLACK IRISH”商标,指定商品包括:第30类:热巧克力;咖啡;第32类:啤酒;黑啤酒和波特啤酒;第33类:含有威士忌,奶油利口酒和/或卜丁酒的咖啡酒精饮料。

IRIS配置管理在铁路信号工程项目中的实践与应用

结合铁路项目实践,阐述I R I S配置管理在铁路信号工程项目上的实践与应用。通过运用I R I S配置管理的相关技术管理手段,在项目生命周期内对保证产品的可追溯性、安全性和可靠性,起到非常重要的支撑作用。

A CLASS OF INVERSE QUOTIENT CURVATURE FLOW IN THE ADS-SCHWARZSCHILD MANIFOLD

In this paper,we study the asymptotic behavior of a class of inverse quotient curvature flow in the anti-de Sitter-Schwarzschild manifold.We prove that under suitable convex conditions for the initial hypersurface,one can get the long-time existence for the inverse curvature flow.Moreover,we also get that the principal curvatures of the evolving hypersurface converge to 1 when t→+∞.

Exogenous addition of nitrate nitrogen regulates the uptake and translocation of lead (Pb) by Iris lacteal Pall. var. chinensis (Fisch.) Koidz.

Since Pb is a non-biodegradable inorganic pollutant and a non-essential metal,its long-term presence in soil poses a great threat to the environment.Iris lactea Pall.var.chinensis(Fisch.)Koidz.,a perennial dense bush herb with high resistance of Pb and wide adaptability,was used in pot experiments to study the effects of exogenous nitrate N(NO_(3)^(–)-N)on the absorption and transportation of Pb and plant growth under different Pb concentrations.Then,the mechanism of NO_(3)^(-)-N affecting Pb and nutrient uptake and transport was explored.The concentration of Pb in the experiment ranged from 0 to 1600 mg/kg,and the added concentration of NO_(3)^(-)-N was 0.0–0.3 g/kg.The results showed that I.lactea was highly tolerant to Pb,and the shoot fraction was more sensitive to varied Pb concentrations in the soil than the root fraction.This protective function became more pronounced under the condition of raised Pb concentration in the soil.When the concentration of Pb in the soil reached 800 mg/kg,the highest Pb content of I.lactea was found under the condition of 0.1 g/kg of NO–3-N addition.When Pb concentration in the soil increased to 1600 mg/kg,the increase in NO_(3)^(-)-N addition promoted Pb uptake by the root.To ensure the well growth of I.lactea and the effect of remediation of Pb-contaminated soil,the recommended concentration of NO–3-N in the soil is 0.1 g/kg.This result provides a theoretical basis for exogenous N regulation of phytoremediation of Pb-contaminated soil.

Microcurvature landscapes induce neural stem cell polarity and enhance neural differentiation

Tissue curvature has long been recognized as an important anatomical parameter that affects intracellular behaviors,and there is emerging interest in applying cell-scale curvature as a designer property to drive cell fates for tissue engineering purposes.Although neural cells are known to undergo dramatic and terminal morphological changes during development and curvature-limiting behaviors have been demonstrated in neurite outgrowth studies,there are still crucial gaps in understanding neural cell behaviors,particularly in the context of a three-dimensional(3D)curvature landscape similar to an actual tissue engineering scaffold.In this study,we fabricated two substrates of microcurvature(curvature-substrates)that present a smooth and repeating landscape with focuses of either a concave or a convex pattern.Using these curvature-substrates,we studied the properties of morphological differentiation in N2a neuroblastoma cells.In contrast to other studies where two-dimensional(2D)curvature was demonstrated to limit neurite outgrowth,we found that both the concave and convex substrates acted as continuous and uniform mechanical protrusions that significantly enhanced neural polarity and differentiation with few morphological changes in the main cell body.This enhanced differentiation was manifested in various properties,including increased neurite length,increased nuclear displacement,and upregulation of various neural markers.By demonstrating how the micron-scale curvature landscape induces neuronal polarity,we provide further insights into the design of biomaterials utilizing the influence of surface curvature in neural tissue engineering.

Assessment of iris volume in glaucoma patients with type 2 diabetes mellitus by AS-OCT

AIM:To examine the change of iris volume measured by CASIA2 anterior segment optical coherence tomography(ASOCT)in glaucoma patients with or without type 2 diabetes mellitus(T2DM)and explore if there is a correlation between hemoglobin A1c(HbA1c)level and iris volume.METHODS:In a cross-sectional study,72 patients(115 eyes)were divided into two groups:primary open angle glaucoma(POAG)group(55 eyes)and primary angle-closure glaucoma(PACG)group(60 eyes).Patients in each group were separately classified into patients with or without T2DM.Iris volume and glycosylated HbA1c level were measured and analyzed.RESULTS:In the PACG group,diabetic patients'iris volume was significantly lower than those of non-diabetics(P=0.02),and there was a significant correlation between iris volume and HbA1c level in the PACG group(r=-0.26,P=0.04).However,diabetic POAG patients'iris volume was noticeably higher than those of non-diabetics(P=0.01),and there was a significant correlation between HbA1c level and iris volume(r=0.32,P=0.02).CONCLUSION:Diabetes mellitus impact iris volume size,as seen by increased iris volume in the POAG group and decreased iris volume in the PACG group.In addition,iris volume is significantly correlated with HbA1c level in glaucoma patients.These findings imply that T2DM may compromise iris ultrastructure in glaucoma patients.

Variable Curvature Modeling Method of Soft Continuum Robots with Constraints

The inherent compliance of continuum robots holds great promise in the fields of soft manipulation and safe human–robot interaction.This compliance reduces the risk of damage to the manipulated object and its surroundings.However,continuum robots possess theoretically infinite degrees of freedom,and this high flexibility usually leads to complex deformations when subjected to external forces and positional constraints.Describing these complex deformations is the main challenge in modeling continuum robots.In this study,we investigated a novel variable curvature modeling method for continuum robots,considering external forces and positional constraints.The robot configuration curve is described using the developed mechanical model,and then the robot is fitted to the curve.A ten-section continuum robot prototype with a length of 1 m was developed in order to validate the model.The feasibility and accuracy of the model were verified by the ability of the robot to reach target points and track complex trajectories with a load.This work was able to serve as a new perspective for the design analysis and motion control of continuum robots.

Iris Liveness Detection Using Fragmental Energy of Haar Transformed Iris Images Using Ensemble of Machine Learning Classifiers

Contactless verification is possible with iris biometric identification,which helps prevent infections like COVID-19 from spreading.Biometric systems have grown unsteady and dangerous as a result of spoofing assaults employing contact lenses,replayed the video,and print attacks.The work demonstrates an iris liveness detection approach by utilizing fragmental coefficients of Haar transformed Iris images as signatures to prevent spoofing attacks for the very first time in the identification of iris liveness.Seven assorted feature creation ways are studied in the presented solutions,and these created features are explored for the training of eight distinct machine learning classifiers and ensembles.The predicted iris liveness identification variants are evaluated using recall,F-measure,precision,accuracy,APCER,BPCER,and ACER.Three standard datasets were used in the investigation.The main contribution of our study is achieving a good accuracy of 99.18%with a smaller feature vector.The fragmental coefficients of Haar transformed iris image of size 8∗8 utilizing random forest algorithm showed superior iris liveness detection with reduced featured vector size(64 features).Random forest gave 99.18%accuracy.Additionally,conduct an extensive experiment on cross datasets for detailed analysis.The results of our experiments showthat the iris biometric template is decreased in size tomake the proposed framework suitable for algorithmic verification in real-time environments and settings.

Trimmable bandgap reference circuit with exponential curvature compensation

This paper proposes an improved exponential curvature-compensated bandgap reference circuit to exploit the exponential relationship between the current gainβof the bipolar junction transistor(BJT)and the temperature as well as reduce the influence of resistance-temperature dependency.Considering the degraded circuit performance caused by the process deviation,the trimmable module of the temperature coefficient(TC)is introduced to improve the circuit stability.The circuit has the advantages of simple structure,high linear stability,high TC accuracy,and trimmable TC.It consumes an area of 0.09 mm^(2)when fabricated by using the 0.25-μm complementary metal-oxide-semiconductor(CMOS)process.The proposed circuit achieves the simulated power supply rejection(PSR)of about-78.7 dB@1 kHz,the measured TC of~4.7 ppm/℃over a wide temperature range from-55℃to 125℃with the 2.5-V single-supply voltage,and the tested line regulation of 0.10 mV/V.Such a high-performance bandgap reference circuit can be widely applied in high-precision and high-reliability electronic systems.

Numerical simulation of a truncated cladding negative curvature fiber sensor based on the surface plasmon resonance effect

A refractive index(RI)sensor based on the surface plasmon resonance effect is proposed using a truncated cladding negative curvature fiber(TC-NCF).The influences of the TC-NCF structure parameters on the sensing performances are investigated and compared with the traditional NCF.The simulation results show that the proposed TC-NCF RI sensor has an ultra-wide detection range from 1.16 to 1.43.The maximum wavelength sensitivity reaches 12400 nm/RIU,and the corresponding R^(2)of the polynomial fitting equation is 0.9999.The maximum and minimum resolutions are 2.56×10^(-5)and 8.06×10^(-6),respectively.In addition,the maximum amplitude sensitivity can reach-379.1 RIU^(-1)when the RI is chosen as 1.43.The proposed TC-NCF RI sensor could be useful in biochemical medicine,environmental monitoring,and food safety.