THREE KINDS OF DENTABILITIES IN BANACH SPACES AND THEIR APPLICATIONS

In this paper,we study some dentabilities in Banach spaces which are closely related to the famous Radon-Nikodym property.We introduce the concepts of the weak^(*)-weak denting point and the weak^(*)-weak^(*)denting point of a set.These are the generalizations of the weak^(*)denting point of a set in a dual Banach space.By use of the weak^(*)-weak denting point,we characterize the very smooth space,the point of weak^(*)-weak continuity,and the extreme point of a unit ball in a dual Banach space.Meanwhile,we also characterize an approximatively weak compact Chebyshev set in dual Banach spaces.Moreover,we define the nearly weak dentability in Banach spaces,which is a generalization of near dentability.We prove the necessary and sufficient conditions of the reflexivity by nearly weak dentability.We also obtain that nearly weak dentability is equivalent to both the approximatively weak compactness of Banach spaces and the w-strong proximinality of every closed convex subset of Banach spaces.

以范可尼综合征和早发肾功能异常起病的Dent病1家系报道并文献复习

Dent病(Dent disease)是一种罕见的X连锁隐性遗传性的近端肾小管疾病,因CLCN5基因(Dent病1型)和OCRL基因(Dent病2型)突变所致[1-2],临床主要特征为小分子蛋白尿(low-molecular weight proteinuria,LMWP)、高钙尿症(hypercalciuria)和肾钙质沉着症(nephrocalcinosis),随病程进展部分患者可出现肾功能异常或肾衰竭[3-5]。此外,Dent病临床还可以有其他多种表现,包括泛氨基酸尿、磷酸盐尿、糖尿症、血尿、尿酸化功能障碍、佝偻病或骨软化症等[6-7]。

表现为大量蛋白尿的儿童Dent病一例

本文报道1例表现为大量蛋白尿的Dent病患儿诊疗过程。患儿男性,3岁1个月,常规体检时发现有大量蛋白尿,无低白蛋白血症,尿蛋白电泳提示以小分子量蛋白为主,同时伴高钙尿症,有阴离子间隙正常的代谢性酸中毒,无糖尿,无氨基酸尿,肾脏超声未见肾脏钙质沉着。患儿无生长发育落后及肾脏疾病家族史。完善全外显子组基因检测到OCRL1基因第15号外显子存在1处错义变异c.1477C>T(p.Arg493Trp)。诊断Dent病明确后,限制高钙、高钠及高草酸盐饮食摄入,同时加用枸橼酸钾颗粒及氢氯噻嗪口服。目前随访2个月,尿钙水平下降,肾功能稳定。本文通过典型病例报道及既往文献回顾,以期提高临床医师对该疾病的认识,并为该疾病的诊治提供借鉴。

1例儿童1型Dent病伴Bartter综合征病例分析并文献复习

目的:分析1例1型Dent病伴Bartter综合征样患儿的临床症状及诊疗过程,以提高临床对该疾病的认识。方法:采用回顾性分析方法,收集我院经临床特征和基因检测确诊的1例1型Dent病伴Bartter综合征患儿的临床资料,分析其临床特征及诊疗过程并复习文献。结果:本例患儿以Bartter综合征样表现(顽固性低钾血症,血浆肾素、醛固酮水平升高,血压正常)为初始表现,并有尿蛋白定量明显升高,以低分子量蛋白(LMWP)尿为主,α1、β2微球蛋白(MG)水平明显升高,基因分析提示CLCN5基因c.1265-c.1266 insA(半合子突变)。但本例患儿初始肾功能正常,泌尿系统超声检查结果未见异常。初期采用饮食调控(如低草酸盐、低钠、低钙等),口服补钾及盐酸贝那普利0.25 mg/(kg·d)治疗1个月后,发生急性肾损伤,给予甲泼尼龙及血液净化治疗后肾功能好转。结论:Dent病临床表型复杂,需及时完善基因检测协助诊断,具有Bartter综合征临床症状的Dent病患者易发展为肾功能衰竭,应及时评估肾功能及长期规律随访。

Finite element analysis of stiffness and static dent resistance of aluminum alloy double-curved panel in viscous pressure forming

The static dent resistance performance of the aluminum alloy double-curved panel formed using viscous pressure forming (VPF)was studied by finite element analysis,which mainly considers the forming process conditions.The whole simulation consisting of three stages,i.e.,forming,spring-back and static dent resistance,was carried out continuously using the finite element code ANSYS.The influence of blank holder pressure(BHP)and the drawbead on the stiffness and the static dent resistance of the panels formed using VPF was analyzed.The results show that the adequate setting of the drawbead can increase the plastic deformation of the double-curved panel,which is beneficial to the initial stiffness and the static dent resistance.There is an optimum BHP range for the stiffness and the static dent resistance.

Shear Failure of a Clamped Dented Tubular Beam Under Lateral Impact

The shear failure of a rigid-plastic dented clamped tubular beam under the lateral impact of a mass is investigated. Both the denting and the impact point are in the middle span of the beam. It is assumed that denting does not spread during the shear sliding. Numerical results show that the axial force and lateral deflection of the beam are very small at the moment of the occurence of shear failure, which means that the finite deformation effect can be neglected in the shear failure analysis. Also, some aspects of the initial impact energy are investigated.

Effects of Controlled-Release Fertilizers and Their Application Methods on Germination and Seedling Growth of Dent and Sweet Corns

Effects of controlled-release fertilizers (CRFs) (C-AS, polyolefin coated ammonium sulfate, 50-day-type; Dd-LP, polyolefincoated urea with dicyandiamide, 40-day-type; C-ANP, polyolefin coated ammonium nitrate phosphate, 40-day-type; andC-DAP, polyolefin coated diammonium acid phosphate, 40-day-type), ammonium sulphate and no fertilizer control, andtheir application methods (spot, band, surface and mixed) on germination and seedling development of sweet corn (Zeamays L.var. saccharata Sturt.) and dent corn (Zea mays L.var. indentata Sturt.) were investigated in a greenhouse. Underco-situs application (band and spot) of CRFs, there were no obvious differences in the germination speed and rate for bothdent corn and sweet corn relative to control. Mortality rates of sweet corn seedlings under co-situs application were highin experiment 1, but were very low in experiment 2, because the environmental conditions were different in the twoexperiments. That is, under lower temperature and weaker sunlight, young seedlings easily die due to high soil nutrientconcentration and slow growth speed of corn. Shoot weight of both dent and sweet corn did not greatly decrease inexperiment 1. In experiment 2, there were no significant differences in shoot and root weight of both corns between co-situs and surface or mixed application methods. However, with spot and band application of ammonium sulfate, shoot androot weight were significantly reduced. Soil EC and pH were considerably affected by co-situs application, especially atthe fertilizer application site. For both dent and sweet corn, EC in the 0-3 cm soil was significantly higher under co-situsapplication and surface application than that under mixed application, whereas in the 3-6 cm soil depth the situation wasreversed. Compared with control, mixed application of CRFs decreased soil pH slightly (0-3 cm depth) or greatly (3-6 cmdepth).

Wear Resistance and Indentation Behavior of Equiatomic Superelastic TiNi and 60NiTi

Indentation and reciprocating wear tests are carried out to study dent and wear resistance of superelastic Ti-Ni alloys. The effect of loading rate on the superelastic behavior of TiNi under indentation loading is investigated and compared to a new generation of shape memory alloys, i.e., 60NiTi. Only limited amount of work has been done to investigate the dependency of superelasticity on loading rate of TiNi under localized compressive loads, but much work is directed towards understanding the effect of strain rate on tensile properties. Understanding the superelastic behavior helps to employ superelastic alloys in applications where high impact loading is expected as in bearings and gears. In the present study, it is found that dent resistance of Ti-Ni alloy is not significantly affected by loading rate (within the employed loading conditions). It has also been found that new-generation 60NiTi alloy exhibits superior wear and dent resistance, as well as higher hardness compared to equiatomic TiNi.

Standards and methods for dent assessment and failure prediction of pipelines:A critical review

Dent,a common mechanical damage on pipelines,is associated with a significant local plastic deformation.Dents can cause pipeline failures,especially when they are combined with other types of defects such as gouges,fatigue,corrosion,and cracks.In this work,a systematic review of various assessment methods and standards for pipeline dents,including the combination of a dent with other defects,is conducted.Generally,the methods available today are not sufficiently accurate and reliable to assess pipeline dents,especially the dent-defect combinations.For plain dents on pipelines,both the depthbased criterion and the strain-based criterion are commonly used in engineering.Their main problems include inaccuracy and conservatism.For a dent combined with other defects,the existing assessment techniques are not mature enough to give reliable results.Both experimental testing and numerical modeling through finite element(FE)analysis are capable of investigating the influence of dents and dent-defect combinations on burst failure pressure of the pipelines,although an approximation to the reality is still the main difficulty existing in the experimental testing and FE analysis.Nowadays,relevant studies on assessment techniques for plain dents,a dent with fatigue and a dent with a single gouge have been common in literature.The combinations of a dent with corrosion or cracks have been rarely assessed due to complicated mechanisms involving a multi-physics coupling effect.Development of novel assessment methods by integrating mechanical stress and strain,electrochemical reactions and steel metallurgy will be a key topic to accurately assess the dent-defect combinations for improved pipeline integrity.

Investigation of Highly Designable Dented Structures in HP Model with Hydrogen Bond Energy

Some highly designable protein structures have dented on the surface of their native structures, and are not full compactly folded. According to hydrophobic-polar （HP） model the most designable structures are full compactly folded. To investigate the designability of the dented structures, we introduce the hydrogen bond energy in the secondary structures by using the secondary-structure-favored HP model proposed by Ou-yang etc. The result shows that the average designability increases with the strength of the hydrogen bond. The designabilities of the structures with same dented shape increase exponentially with the number of secondary structure sites. The dented structures can have the highest designabilities for a certain value of hydrogen bond energy density.

Time-Dependent Reliability Analysis of Offshore Structures

During the life of an offshore structure, its structural strength declines due to various kinds of damages related to the time factor. In this paper, four major kinds of damages, including damages caused by fatigue, dent, corrosion and marine life, are discussed. Based on these analyses, formulas for the evaluation of the damaged structure reliability are derived. Furthermore the computer program ISM for the analysis of structural reliability is developed by the use of Advanced First Order Second Moment method and Monte-Carlo Importance Sampling method. The reliability of a turbular joint and a beam are studied as numerical examples. The results show that the theory and the analysis method given in this paper are reasonable and effective.

Research on dent resistance of lightweight three-piece cans

An experimental apparatus and a numerical simulation model were built for investigating the dent resistance of lightweight three-piece cans.The dent resistance of raw materials 0.19 mm T4 and 0.17 mm DR7M was compared.It was found that when the thickness reduced from 0.19 to 0.17 mm,the dent resistance became about 80％ of that before thinning.This provides a guidance for the continuous thinning of three-piece cans.

A NEW MODEL FOR CALCULATING PROPAGATION PRESSURE AND INITIATION PRESSURE OF PIPELINES WITH A LOCAL DENT

An analytical model of a ring with six yield hinges and two deformable arc segments is presented for. the prediction of the buckle propagation pressure and initiation pressure in offshore pipelines. The configuration of a fully collapsed ring is considered as a real dumbbell shape with a line touch between two 'bells', instead of the dumbbell shape with a point touch of two diametrically opposite points. Calculations are performed assuming that the dominant effect on the plastic energy dissipation has the circumferential bending mode. For the linear strain-hardening materials it is found that theoretical predictions based on the above model for both propagation pressure and initiation nressure are in good agreement with experimental results of Kyriakides et al.

Dent病研究进展

Dent病(Dent disease)是一种罕见的X连锁隐性遗传肾小管疾病。已被证实CLCN5及OCRL1为其致病基因,另有部分病例致病基因不明。随着Dent病分子遗传学研究的不断深入,关于Dent病的研究有了新的进展,现就Dent病的致病基因及其致病机制、临床表型及治疗进展等方面进行综述。

A Summit of Little Substance

The US-Africa Leaders Summit was held in Washington D.C.from 13 to 15 December 2022.As expected,it drew considerable media attention.Coming eight years after the first such summit held in 2014,it did not have much to look back in terms of antecedents and continuity.

水蒸气在褐煤孔隙中的吸附行为:试验研究与分子动力学模拟

深入理解水在褐煤上的吸附是褐煤干燥提质技术的理论基础之一。采用傅里叶变换红外光谱(FTIR)、扫描电子显微镜(SEM)和低温氮吸附/脱附试验分析了褐煤的含氧官能团和孔隙结构,利用水蒸气吸附/脱附试验和分子动力学(MD)模拟探究了水蒸气在褐煤孔隙中的吸附行为。研究结果表明:褐煤样品丰富的含氧官能团和较多的微孔、中孔(孔径约2 nm),为水蒸气提供了吸附位点和吸附场所。水蒸气在煤样上的吸附过程可分为3个阶段。第1阶段,相对蒸气压(P/P_(0))<0.21,水分子直接吸附于含氧官能团上,此时的吸附速度最大;第2阶段(P/P_(0)=0.21~<0.71),水分子与已吸附的水分子相互作用,促使水团簇逐渐生长;第3阶段(P/P_(0)≥0.71),水团簇填充孔隙,并发生毛细凝聚,此时的吸附速度略大于第2阶段。根据Dent模型对水蒸气吸附等温线的拟合结果,吸附类型属于多级吸附,包括初级吸附(第1阶段)和次级吸附(第2、3阶段)。初级吸附能(-48.77 kJ/mol)显著大于水的液化热(E L=-43.99 kJ/mol),而次级吸附能(-42.28 kJ/mol)略小于E L,表明吸附于褐煤的水呈液态。水蒸气脱附过程存在明显的脱附迟滞现象,表明水蒸气吸附稳定,较难去除,其中高压迟滞发生在P/P_(0)≈0.4~0.9,主要由毛细凝聚和“墨水瓶”效应引起;而低压迟滞发生在P/P_(0)<0.4,由水分子与含氧官能团间强相互作用引起。MD模拟结果与水蒸气吸附/脱附等温线分析结果一致,水分子优先吸附在孔隙中,与孔隙壁的含氧官能团形成氢键,且其扩散系数(2.98×10^(-5)cm^(2)/s)与液态水的分子扩散系数相近。

Dent病6例临床诊治分析

目的 探讨Dent 病的诊断及治疗.方法 回顾性分析2014 年1 月至2015 年8 月收治的曾被外院误诊为肾病综合征的6 例Dent 病患儿的临床特点、诊治过程以及相关致病基因突变分析.结果 6例患儿均为男性,年龄4.5 - 9.8 岁,临床主要表现为达肾病水平的蛋白尿,有-过性低白蛋白血症（26 - 30 g/L）,均无明显水肿、高胆固醇血症.其中4 例患儿行肾活检,2 例为轻度系膜增生性肾小球肾炎、2 例为局灶节段性肾小球硬化.6 例患儿在对足量激素耐药后均联用至少一种或多种免疫抑制剂,蛋白尿均未见明显变化.入院后检查示低分子蛋白尿,肾早期损伤指标α1 微球蛋白（α1-MG）与微量白蛋白（MA）的比值均〉 1,伴高钙尿症、不伴肾功能异常,其中2 例B超可见肾脏钙化影像,符合Dent 病临床诊断.进一步的基因分析证实6 例患儿均存在CLCN5 基因致病突变.结论 作为一种罕见的遗传性肾小管疾病,Dent 病在临床上易被误诊误治,应引起临床儿科医师的重视.肾早期损伤指标α1-MG/MA 〉 1,可作为肾小管性蛋白尿的诊断标准之一.

Dent病合并肾衰竭2例报告并文献复习

目的探讨儿童Dent病合并肾衰竭的病因及预后。方法分析2014年1月至2016年12月收治的2例Dent病合并肾衰竭患儿的临床资料,并结合文献进行复习。结果 2例患儿均为男性,年龄分别为8、10岁;既往肾功能均正常,无肾脏钙化;肾衰竭发病前1周内均有上呼吸道病毒感染史。例1疾病急性期(10天)肾活检提示合并急性小管间质性肾炎,经激素治疗后肾功能完全恢复;例2病程6个月时肾活检提示合并亚急性小管间质性肾炎,经激素治疗后肾功能稍有改善但未恢复正常。结论对于Dent病患儿发生急性肾衰竭,特别是有上呼吸道病毒感染等诱因者,应及早行肾活检,以除外合并急性间质性肾炎的可能,从而及时治疗、改善预后。

儿童2型Dent病1例并文献复习

目的总结1例2型Dent病患儿临床资料,提高对该病的认识。方法报道1例2型Dent病患儿的临床发现、相关实验室检查指标和肾活检病理改变。对该家系相关成员行CLCN5和OCRL基因外显子及附近调控区域直接测序,分析突变位点,并文献复习。结果患儿,男,6岁起病,首发症状为单纯性蛋白尿,未见先天性白内障、智力低下、认知障碍及发育迟缓。实验室检查提示低分子蛋白尿,高钙尿症,镜下血尿,血清乳酸脱氢酶和磷酸肌酸激酶增高,肾活检病理提示轻微病变。患儿CLCN5和OCRL基因测序分析发现,CLCN5基因未见致病性突变,ORCL基因c.260del A(p.Q87fs105X)纯合突变,确诊为2型Dent病。家系OCRL基因突变分析显示,患儿父亲c.260del A未检出突变,母亲携带c.260del A杂合突变。c.260del A突变为移码突变,可导致OCRL基因编码蛋白截短。结论 2型Dent病以低分子蛋白尿、高钙尿症和镜下血尿为特征,血清乳酸脱氢酶、磷酸肌酸激酶增高和OCRL基因纯合移码突变支持2型Dent病诊断。

合并肾囊性病变儿童1型Dent病1例报告

目的探讨儿童Dent病1型合并肾囊性病变的可能发病原因。方法回顾1例16岁男性肾囊性病变患儿的临床资料,并复习相关文献。结果患儿发现蛋白尿、双肾多发囊肿4年,肾功能异常3年,临床主要表现为肾病水平的小分子蛋白尿、高钙尿症、肾功能异常并进行性加重、双肾多发囊肿、低钾血症。肾脏病理为局灶节段性肾小球硬化伴肾小管间质损伤。CLCN 5基因突变分析示c. 1975 delC(p.R 659 Gfs*7),NPHP相关基因未见突变。诊断为Dent病1型合并肾囊性病变、慢性肾脏病。结论 Dent病1型合并肾囊性病变较为罕见,其确切机制尚不清楚。