微创全瓷贴面配合DSD技术修复前牙切缘切角缺损美学效果观察

目的:探讨微创全瓷贴面配合数字化微笑设计(Digital smile design,DSD)技术修复前牙切缘切角缺损的美学效果。方法:选取2019年1月-2022年1月笔者医院接诊的78例前牙切缘切角缺损患者为研究对象,采用区组随机化法分为观察组(116颗患牙)和对照组(120颗患牙),每组39例。对照组采用微创全瓷贴面修复,观察组给予微创全瓷贴面联合DSD技术进行修复。比较两组患者治疗6个月后的满意度、美学效果[美国公共卫生署评估标准(United states public health service,USPHS)],对比治疗前后两组患者的红色美学指数、牙周健康指数[牙龈指数(Gingival index,GI)、牙菌斑指数(Plaque index,PLI)、龈沟出血指数(Sulcus bleeding index,SBI)]的变化。结果:治疗6个月后,两组美学效果各维度评级有显著差异,观察组治疗满意率、红色美学指数评分均显著高于对照组(P<0.05);治疗6个月后,两组GI、PLI、SBI均明显降低,且观察组显著低于对照组(P<0.05)。结论:微创全瓷贴面联合DSD技术修复前牙切缘切角缺损可有效改善牙齿美学效果,提高患者治疗满意度,适合临床推广。

38,XX-DSD(SRY^(-))间性猪分子病因学的研究进展

生猪种业是国家战略性、基础性核心产业,其为养猪业的长期稳定发展提供了重要支撑。具有XX染色体型的性别发育异常(Disorder of Sex Development with XX karyotype,XX-DSD)的间性猪,其生殖系统异常发育,严重制约了种猪的高效生产,影响了生猪养殖的经济效益。建立间性猪的精准分子诊断技术能确保引种优化和种猪遗传改良,为人类性别发育异常提供动物模型,助力农用猪和医用猪的高质量发展。本文综述了人类及其他模式动物XX-DSD的分类、调控因素和候选基因变异,重点阐述了间性猪的分类、表征、遗传力和分子遗传研究,以期为间性猪的遗传诊断提供重要的理论参考。

DSD酸-三嗪-四辛基双季铵盐荧光增白剂的合成及性能

以4,4′-二氨基二苯乙烯-2,2′-二磺酸、2,4,6-三氯-1,3,5-三嗪、二辛基甲基叔胺、4-氨基苯甲酸为原料,经过连续缩合反应制备出一种结构新颖的DSD酸-三嗪-四辛基双季铵盐荧光增白剂。采用傅里叶变换红外光谱(FT-IR)和核磁共振氢谱(1 H NMR)对目标化合物进行结构表征,并对荧光性能、增白效果、色度指数、表面活性和表面整理作用进行了测试。结果表明:DSD酸-三嗪-四辛基双季铵盐荧光增白剂具有较强的荧光发射性能;对滤纸进行染色增白处理后,白度值由84.58增加至124.81,且滤纸外观更加光滑平整;目标化合物具有表面活性作用,使水溶液的临界胶束浓度为7.68×10^(-3 )mol/L,表面张力为30.81 mN/m。

Variability of Raindrop Size Distribution during a Regional Freezing Rain Event in the Jianghan Plain of Central China

The characteristics of the raindrop size distribution(DSD)during regional freezing rain(FR)events that occur throughout the phase change(from liquid to solid)are poorly understood due to limited observations.We investigate the evolution of microphysical parameters and the key formation mechanisms of regional FR using the DSDs from five disdrometer sites in January 2018 in the Jianghan Plain(JHP)of Central China.FR is identified via the size and velocity distribution measured from a disdrometer,the discrete Fréchet distancemethod,surface temperature,human observations,and sounding data.With the persistence of precipitation,the emergence of graupel or snowflakes significantly reduces the proportion of FR.The enhancement of this regional FR event is mainly dominated by the increase in the number concentration of raindrops but weakly affected by the diameters.To improve the accuracy of quantitative precipitation estimation for the FR event,a modified second-degree polynomial relation between the shapeμand slopeΛof gamma DSDs is derived,and a new Z-R(radar reflectivity to rain rate)relationship is developed.The mean values of mass-weighted mean diameters(D_(m))and generalized intercepts(lgN_(w))in FR are close to the stratiform results in the northern region of China.Both the melting of tiny-rimed graupels and large-dry snowflakes are a response to the formation of this regional FR process in the JHP,dominated by the joint influence of the physical mechanism of warm rain,vapor deposition,and aggregation/riming coupled with the effect of weak convective motion in some periods.

Statistical Characteristics of Raindrop Size Distribution in the South China Monsoon Region(Guangdong Province)

While heavy rainfall frequently takes place in southern China during summer monsoon seasons,quantitative precipitation forecast skills are relatively poor.Therefore,detailed knowledge about the raindrop size distribution(DSD)is useful in improving the quantitative precipitation estimation and forecast.Based on the data during 2018-2022 from 86stations in a ground-based optical disdrometer measurement network,the characteristics of the DSD in Guangdong province are investigated in terms of the particle size distribution(N(D)),mass-weighted mean diameter(Dm) and other integral DSD parameters such as radar reflectivity(Z),rainfall rate(R) and liquid water content(LWC).In addition,the effects of geographical locations,weather systems(tropical cyclones,frontal systems and the summer monsoon) and precipitation types on DSD characteristics are also considered.The results are shown as follows.1) Convective precipitation has a broader N(D) and larger mean particle diameter than the stratiform precipitation,and the DSD observations in Guangdong are consistent with the three-parameter gamma distribution.The relationships between the Z and R for stratiform and convective precipitation are also derived for the province,i.e.,Z=332.34 R1.32and Z=366.26R1.42which is distinctly different from that of the Next-generation Weather Radar(NEXRAD) Z-R relationship in United States.2) In the rainy season(April-September),the Dm, R and LWC are larger than those in the dry season(OctoberMarch).Moreover the above parameters are larger,especially in mid-May,which is the onset of the South China Sea summer monsoon.3) The spatial analysis of DSD shows that the coastal station observations indicate a smaller Dmand a larger normalized intercept parameter(log10Nw),suggestive of maritime-like rainfall.Dmis larger and log10Nwis smaller in the inland area,suggestive of continental-like rainfall.4) Affected by such weather systems as the tropical cyclone,frontal system and summer monsoon,the DSD shows characteristics with distinct differences.Furthermore,frontal system rainfall tends to present a continental-like rainfall,tropical cyclone rainfall tends to have a maritime-like rainfall,and summer monsoon rainfall characteristic are between maritime-and continental-like cluster(raindrop concentration and diameter are higher than continental cluster and maritime cluster,respectively.)

Understanding the Variability of Z-R Relationships Caused by Natural Variations in Raindrop Size Distributions(DSD):Implication of Drop Size and Number

In the issue of rainfall estimation by radar through the necessary relationship between radar reflectivity Z and rain rate R (Z-R), the main limitation is attributed to the variability of this relationship. Indeed, several pre-vious studies have shown the great variability of this relationship in space and time, from a rainfall event to another and even within a single rainfall event. Recent studies have shown that the variability of raindrop size distributions and thereby Z-R relationships is therefore, more the result of complex dynamic, thermody-namic and microphysical processes within rainfall systems than a convective/stratiform classification of the ground rainfall signature. The raindrop number and size at ground being the resultant of various processes mentioned above, a suitable approach would be to analyze their variability in relation to that of Z-R relation-ship. In this study, we investigated the total raindrop concentration number NT and the median volume di-ameter D0 used in numerous studies, and have shown that the combination of these two ‘observed’ parame-ters appears to be an interesting approach to better understand the variability of the Z-R relationships in the rainfall events, without assuming a certain analytical raindrop size distribution model (exponential, gamma, or log-normal). The present study is based on the analysis of disdrometer data collected at different seasons and places in Africa, and aims to show the degree of the raindrop size and number implication in regard to the Z-R relationships variability.

What Impact on Phenotype for Patients with Karyotype 46, XX DSD SRY Positive at CHU Dantec in Senegal: About 5 Cases?

Background: In disorders of sexual differentiation, sexual development may not conform to the chromosomal structure, thus forming different types of abnormalities. Among these abnormalities is syndrome 46, XX DSD where most patients are female phenotype with clitoral hypertrophy that can go to complete masculinization especially in the presence of the SRY gene. Objective: The goal of this work is to demonstrate a relationship between the genotype and the phenotype in five patients karyotype 46, XX with the presence of the SRY gene. Methodology: The study involves five patients referred to the laboratory under suspicion of sexual development anomalies. The diagnosis took place through hormonal and echography examinations, a classic cytogenetic study (Barr chromatin and karyotype) and an amplification of the SRY gene located on the Y chromosome. The resulting PCR products were sent for sequencing. Results: Based on the results of clinical and paraclinical tests carried out it was found clitoral hypertrophy, the presence of clitoris penis for some, presence of normal penis for others. In addition, echography revealed a lack of female internal genitalia (P2, P3), and a presence of testicles (P3, P4, P5). Genetic analysis (chromosomal and molecular) showed a karyotype 46, XX SRY (+) for all patients. New mutations were found c.246 T > A, p.82 Asn82Lys and c.171 G > C, p.57 Gln57His. Conclusion: In our study, we were able to correlate each DSD with karyotype 46, XX to a pathology such as 46, XX DSD testicular, 46, XX DSD with clitoral hypertrophy and ovotestis 46, XX. The next step will undoubtedly be the integration of other molecular techniques (genotyping, FISH, CGH or even the CGH array) to further genetic exploration.

Raindrop Size Distribution Measurements at High Altitudes in the Northeastern Tibetan Plateau during Summer

Characteristics of raindrop size distribution during summer are studied by using the data from six Parsivel disdrometers located in the northeastern Tibetan Plateau.The analysis focuses on convective and stratiform precipitation at high altitudes from 2434 m to 4202 m.The results show that the contribution of stratiform and convective precipitation with rain rate between 1≤R<5 mm h^(-1) to the total precipitation increases with altitude,and the raindrop scale and number concentration of convective precipitation is larger than that for stratiform precipitation.The droplet size spectra of both stratiform and convective precipitation shows a single peak with a peak particle size between 0.31–0.50 mm,and they have essentially the same peak particle size and number concentration at the same altitude.The maximum spectral widths of stratiform clouds are between 4 mm and 5 mm,while those of convective clouds range from 4 mm to 8 mm.The Gamma distribution is more suitable than the Marshall-Palmer distribution in terms of the actual raindrop spectrum distribution.The stratiform precipitation particles are smaller with higher number concentration,while the opposite is true for the convective precipitation particles.The convective precipitation particles drop faster than stratiform precipitation particles when the particle size exceeds 2 mm,and the falling velocity of raindrops after standard curve fitting is underestimated during the observation period.Moreover,conventional radar estimation methods would underestimate the precipitation in the Northeastern Tibetan Plateau.

数字化口腔种植DSD美学修复治疗牙缺失的疗效对比研究

研究牙缺失患者接受数字化口腔种植DSD美学修复治疗的有效性。方法 对2020年-2021年阶段内受诊的牙缺失100例患者开展医学观察,按照是否进行DSD美学修复划分两组,有数字化口腔种植修复的基本修复组、数字化口腔种植DSD美学修复的美学修复组,对比两组患者治疗效果,评估应用数字化口腔种植DSD美学修复价值。结果 干预前,基本修复组、美学修复组患者之间的牙齿咀嚼能力、牙齿固位能力、语言能力指数比较p>0.05。干预后,基本修复组牙齿咀嚼能力均值(6.35±0.79)分、牙齿固位能力均值(6.40±0.65)分、语言能力均值(6.02±0.19)分,均不如美学修复组,p<0.05;干预前,基本修复组、美学修复组患者的种植体稳定性、红色美学和生活质量评分之间p>0.05。干预后,美学修复组种植体稳定性评估均值(89.46±5.13)分、红色美学评估均值(8.92±0.46)分、生活质量评估均值(92.45±3.62)分,均优于基本修复组,p<0.05;基本修复组总干预有效率是80.0%,低于美学修复组干预有效率92.0%,p<0.05。结论 对于牙缺失患者的治疗,应意识到数字化口腔种植DSD美学修复的有效价值,促进患者牙齿功能恢复,提高牙齿稳定性以及红色美学评估结果,保障患者早日恢复,值得推广。

4例46,XY性发育障碍患者遗传学分析

目的:探讨4例46,XY性发育障碍发生的分子机制。方法:收集患者临床病历资料,采集其肝素抗凝外周血进行淋巴细胞培养,染色体G显带技术制备并分析染色体核型,提取外周血DNA行SRY基因检测和测序,SRY基因检测结果阴性者外送标本行性发育相关基因靶向测序,生物信息学方法分析测序结果。结果:查体显示4例患者社会性别均为女性,而外周血淋巴细胞核型分析结果提示核型均为男性(46,XY),社会性别与生物学性别不一致;性别决定基因SRY均为阳性,测序结果提示病例1为SRY基因编码区第5位碱基缺失(c.del5A),病例2为SRY基因编码区第5位碱基发生错义突变(c.5A>T),病例3为SRY基因编码区第6位碱基缺失(c.del6A),病例4的SRY基因检测范围内未见突变位点,靶向测序结果提示雄激素受体基因(AR)编码区发生错义突变(c.2117 A>G);生物信息学软件Mutation taster提示c.del5A、c.del6A和c.2117 A>G等3种突变可能导致疾病发生,c.5A>T突变可能为人群多态现象;Raptor X蛋白质三维结构预测软件分析结果显示SRY基因c.5A>T突变对SRY蛋白的三维构象没有影响,而AR基因c.2117 A>G突变可导致AR蛋白的三维结构明显变化,并增加两个氢键;PolyPhen-2显示SRY基因c.5A>T和AR基因c.2117A>G突变为可能致病;ClinvAR软件分析结果提示4种突变均未见临床病例报道。结论:基因突变可能是导致患者性器官发育异常的原因,基因检测有助于明确诊断以及家庭再生育咨询。

大型风力机叶片前缘的雨滴冲击动力学响应机制

随着近年海上风力机设计的大型化,叶片前缘的雨蚀失效问题变得愈发突出,不仅影响机组的风能转化效率,对结构的稳定运行也构成潜在威胁。采用光滑粒子流体动力学(smooth particle hydrodynamics,SPH)法研究雨滴内部的本构关系,以有限元法(finite element method,FEM)建立叶片前缘的代表性体积单元(representative volume element,RVE)模型,两者相互耦合,研究雨滴在叶片表面形成的冲击响应过程。考虑自然降雨的实际工况,建立与降雨强度相关联的雨滴尺寸模型,以及雨滴的空间分布模型;通过单雨滴的冲击仿真,研究叶片表面冲击载荷以及雨滴内部的速度分布,从而解构雨滴冲击的物理过程,并通过冲击的应力、应变场分析,为潜在损伤区提供评价;建立多雨滴冲击的仿真模型,研究冲击应力场之间的耦合作用以及涂层表面的塑性应变累积效果。研究结果表明,水锤冲击是造成塑性应变累积的关键因素,虽然横向喷射阶段的应力响应幅值小并呈现一定的无序特征,但如果存在多雨滴耦合冲击的情况,则会在耦合区内出现应力峰值,并对叶片变形和失效存在潜在影响。

2024年2月湖北省一次大范围冻雨过程的宏微观特征及形成机制初探

2024年2月长江中下游地区先后出现两次低温雨雪冰冻天气,其中第一次过程(2月1-6日)冻雨表现出量大、范围广、持续时间长、危害性强等特征。为此,基于湖北省80个国家气象站激光雨滴谱仪观测数据,结合气象要素观测资料,对此次冻雨过程进行定量判断,并对其宏微观特征进行定量分析,结果表明:(1)此次过程冻雨区主要集中在江汉平原和武汉城市圈等地,表现为液态降水维持时间长。(2)冻雨时数和冻雨量分布具有较好的一致性,其高值区均呈现西北-东南走向,冻雨时数一般在15h以上,冻雨量超过24mm;冻雨集中期在2月2-3日,此时段各区间其数浓度、液水含量、雨强和粒径站时数占比均显著高于该过程其他时段。(3)各地区平均冻雨滴谱分布呈单峰型,其峰值数密度在200mm^(-3)·mm^(-1)左右。(4)构建的Z-R关系不同于短历时、区域性冻雨过程,能较好地实现对此类冻雨定量估测降水(Quantitative Precipitation Estimation QPE)的估算。整个过程中质量加权平均直径(D_(m))和归一化截距参数(log_(10)N_(w))的平均值分别为1.07mm和3.03。(5)在水汽凝华、丛集和凇附机制的共同影响下,致密霰粒和冰晶聚合物融化形成此次冻雨过程。

DSD酸-三嗪型荧光增白剂研发新进展及发展趋势

在简要介绍荧光增白剂发展状况的基础上,着重介绍了近几年DSD酸-三嗪型荧光增白剂的研究进展,包括改变取代基、开发复配产品、两性荧光增白剂的研究、研制稳定易储存液态型产品、改进基础原料与中间体、应用膜技术纯化荧光增白剂以及不对称型荧光增白剂的研究等,并叙述了此类荧光增白剂的发展趋势,指出具有良好应用性能的产品国产化和产业化,高档专用、复配、两性、不对称型产品的开发,剂型及后处理工艺的研究等可能成为新的研究重点。

反应萃取处理染料中间体H酸和DSD酸工业废水

分别采用三烷基胺 (Alamine 336)和氯化季铵盐 (Aliquat 336)为萃取剂 ,正辛醇为助溶剂 ,煤油为稀释剂 ,进行H酸、DSD酸及其工业废水反应萃取的实验研究 .结果表明 ,萃取率与溶液的pH值有关 ,Alamine 336体系适于酸性较强废水的处理 ,Aliquat 336体系适于中性废水的处理 ;采用多级错流萃取能有效地去除废水中两性官能团化合物和色度 ,去除率达 99%以上 ,反萃率可达 1 0 0 % ,工艺简单易行 。

树枝状大分子PAMAM-DSD的合成及其在造纸中的应用

在低代端酯基PAMAM树形分子(G0.5-COOCH3)末端引入4,4′-二氨基二苯乙烯-2,2′-二磺酸,在常温常压下合成一种高分子荧光增白剂(PAMAM-DSD)。实验显示,在纸张涂布中使用PAMAM-DSD,纸张的白度以及耐光性均得到明显改善。确定了PAMAM-DSD在涂布颜料中的适宜用量。

铁泥海绵铁的制备及其在DSD酸氧化废水处理中的应用

利用DSD酸生产过程产生的铁泥，研制出既能用作常规冶金原料，又能用于处理DSD酸氧化废水的水处理用海绵铁．研究表明：在配碳量27％、反应温度1160℃、反应时间16min的情况下，以铁泥为原料制备的常规海绵铁的金属化率可达90％以上；用于处理DSD酸氧化废水的海绵铁适宜配碳量为29％，用制备出的海绵铁处理DSD酸氧化废水，在pH值3～5、反应时间40min时，出水的CODCr去除率可达68％、色度的去除率达90％、可生化性指标BOD／COD提高到0．425．海绵铁中所含C，Fe3C和其他一些杂质元素，这些元素能与铁在水中形成无数微小原电池产生大量[H]，[OH]和[Fe^2＋]，从而氧化还原废水中的有机物，达到污染物降解和提高废水可生化性的目的．海绵铁的微孔结构非常发达，使其具有比表面积大、活性高的特点．是一种替代常规铁屑的理想材料．

我国DSD酸溶剂法氧化合成工艺工业化解脱瓶颈制约的建议

介绍了国内有关单位用溶剂法氧化合成DSD酸的清洁生产工艺研究进展,分析了该工艺目前还未能用于工业化生产的原因:①工业化生产的一些工程技术难题还有待解决;②溶剂法工艺生产的总成本高于传统的水法工艺;③不少地区的环保执法存在"盲区",地方保护痼疾难除;④政策支持力度不够,企业缺乏积极性;⑤产能过剩竞相降价,企业无力承担科研费用。讨论了溶剂法氧化合成DSD酸工业化的瓶颈制约所在,指出了解决途径,提出了发展建议。

SBR法处理还原段DSD酸废水脱氢酶活性的研究

对SBR法处理还原段DSD酸生产废水处理中污泥活性进行了分析。脱氢酶活性能及时准确地反映污泥活性变化,预知水质波动。在整个代谢过程中,总脱氢酶活性(Dt)和基质脱氢酶活性(Ds)变化规律相似;当了解体系大体情况时,Dt可代替Ds反映污泥活性变化。Dt与可降解COD浓度之间较好的服从莫诺关系式,Dt具有生化反应速率的意义。研究表明,在温度为30℃,葡萄糖投加量为250mg/L,有机负荷为0.6kg(/kg·d),pH值为7的条件下,脱氢酶活性最高。

萃取法处理DSD酸氧化工序废水的研究

本文对萃取法处理ＤＳＤ 酸氧化工序废水进行了研究，确定了废水Ｈ２ＳＯ４三辛胺（ＴＯＡ） － 煤油的萃取体系，并探讨了萃取相比、水相酸度、稀释比、萃取温度、反应搅拌时间、搅拌强度和反萃投碱浓度、反萃温度等一系列处理参数。实验结果表明，经萃取处理后ＤＳＤ 酸氧化工序废水中的ＣＯＤ 及色度去除率分别达９４ ．３ ％ 和９９ ．６ ％ 。

氧化-微电解-吹脱处理DSD酸生产废水的试验

针对DSD酸生产废水温度高,可生化性差,氨氮含量高,难于进行生化处理的特点,采用氧化-微电解-吹脱的工艺进行处理,效果良好。在进水COD和氨氮的平均质量浓度分别为533.6、319.4mg/L,色度为180倍时,处理后出水COD和氨氮的平均质量浓度分别为152.2、29.9mg/L,去除率分别达到71.5%和90.6%,对色度的去除率也达到99%。出水可达到GB8978-1996所规定的二类水质的要求。