Comparison of Testing Methods for Evaluating the Resistance of Alkali-Activated Blast Furnace Slag Systems to Sulfur Dioxide

Alkali-activated systems (AAS) represent an ecologically and economically sustainable inorganic binder as an alternative to ordinary Portland cement (OPC). One of the main benefits of AAS is their durability in aggressive environments, which can be equal or even better than that of OPC. In this paper, the influence of the type of alkaline activator in alkali-activated blast furnace slag (AAS) in terms of resistance to sulfur dioxide corrosion was investigated. The durability testing process was based on the CSN EN ISO 3231 standard and simultaneously compared with mortar samples prepared by using Blastfurnace cement CEM III/A 32.5R. The degradation progress was evaluated by employing several different methods such as observing the compressive strength development, weight change evaluation, non-destructive testing methods like ultrasound or impact echo technique, or visual phenolphthalein technique. Subsequently, fundamental characterization of samples by the XRD method was performed during the degradation test. The obtained results indicate that none of the testing methods used could be prioritized over others to determine the resistance of AAS against the action of sulfur dioxide. For this reason, the durability testing of AAS remains an issue, and the development of specific standards considering the behavior of AAS seems necessary.     

Quantitative processed images acquired by histogram-SNR imaging used to evaluate parenchymal heterogeneity in the liver

Purpose: To evaluate a new system for displaying processed images of liver parenchyma based on quantitative estimation of heterogeneity by texture analysis.Methods: We measured the signal to noise ratio, one of the first-order statistics in the histogram of enveloped amplitude of radio-frequency backscattered echoes, using a 3.75-MHz transducer with texture analysis in conjunction with a new method in which the small ROI (region of interest) is segmented into multiple layers to minimize the influence of tissue attenuation and beam diffraction. In our computerized system, gray-display and color-display images, two types of processed images, were produced from the visual intensity of each small ROI, which was based on its signal to noise ratio. We studied 10 cases of normal liver, 10 cases of fatty liver, and 10 cases of cirrhotic liver. The processed images obtained from these livers were reviewed to observe their features and to compare their usefulness in estimating the heterogeneity of the liver parenchyma with that of conventional B-mode images.Results: Gray-display images of cirrhotic livers appeared much blacker than the images produced from other disorders, and color-display images of cirrhotic liver appeared much bluer or greener than the others. Rate of correct diagnosis from B-mode images was 68.3 ±6.8%; from gray-display images, 85.8±7.4%; and from color-display images, 91.7±8.2%. Rate of correct assessment from B-mode images and gray-display images was significantly correlated (p=0.0015), as was rate of correct assessment from the B-mode images and the color-display images (p=0.0060).Conclusion: The processed images obtained using this computerized system contributed to the correct and objective interpretation of the heterogeneity of the liver parenchyma.     

冬凌草IrCYP71基因的克隆和功能

目的:克隆冬凌草二萜类化合物生物合成途径下游关键酶基因Ir CYP71,进行序列特征分析,对此基因编码的蛋白进行原核表达分析以及亚细胞定位,并对蛋白在宿主细胞表达的条件进行了优化。方法:根据转录组测序所得的Ir CYP71基因片段,克隆出全长c DNA序列;构建p ET28a(+)-Ir CYP71重组质粒,转化到Rosetta感受态细胞,小量表达和大量表达蛋白并鉴定,进行包涵体蛋白的纯化与复性,再对复性蛋白纯化鉴定分析。基于gateway克隆技术构建出PCR8/GW/TOPO-Ir CYP71载体之后与改造Pearleygate104载体重组,之后与农杆菌GV3101重组,转入烟草中瞬时表达,从而进行蛋白亚细胞定位。结果:克隆得到的Ir CYP71基因全长c DNA为1 593 bp,编码530个氨基酸,并在Gen Bank注册(登录号MG800628)。经大肠埃希菌表达系统表达的重组蛋白相对分子质量正确,在62 k Da左右,纯化后的重组蛋白总量有1 mg,蛋白纯度为85%。此蛋白亚细胞定位在细胞核。结论:对冬凌草Ir CYP71基因进行了初步验证,并对基因表达的蛋白进行原核表达和亚细胞定位,使该基因在冬凌草二萜成分的生物合成过程中的作用得到了进一步的阐述。     

Molecular characterization of the genome of duck enteritis virus

The genomic sequence of a strain of duck enteritis virus (DEV) was determined and analyzed in this study. The size of its genome is 158,091 bp in length and the genome is predicted to encode 78 putative proteins and resembles the members of the Alphaherpesvirinae in genomic organization and gene composition. The genome of the virus is composed of a unique long (UL) region, a unique short (US) region, a unique short internal repeat (IRS) region and a unique short terminal repeat (TRS) region. Its genomic arrangement pattern (UL-IRS-US-TRS) corresponds to D-type herpesvirus and is consistent with the members of Varicellovirus and Iltovirus genera. Sequence analysis reveals that the genome of the virus contains 67 genes having homologs in most members of the Alphaherpesvirinae. Out of these genes, one gene has a homolog in cercopithecine herpesvirus 8 which is a virus of Betaherpesvirinae, and 5 genes have homologs in avian herpesviruses. Furthermore, the genome possesses three unique genes without homologs in any other herpesviruses. Like most members of the Alphaherpesvirinae, the genes in the UL region of its genome are well conserved, whereas the gene arrangement of IRS-US is similar to that of Marek's disease virus and equine herpesviruses 1. Therefore, our data based on the genomic analysis suggest that DEV represents an osculant taxonomic entity within the Alphaherpesvirinae.     

图像分割技术在中医舌诊客观化研究中的应用

舌诊是中医四诊的主要内容,是辨证论治的主要依据。客观化研究对中医辨证规范化及中医临床、教学和科研手段的现代化具有重要意义。对舌诊客观化研究中涉及的图像预处理的重要内容——舌体分割提取和舌苔舌质同类区域划分——进行了深入研究,提出了相应算法,通过实验充分证明了算法具有很好的鲁棒性。这给进一步的自动特征提取提供了保障和重要信息。     

A porcine G9 rotavirus strain shares neutralization and VP7 phylogenetic sequence lineage 3 characteristics with contemporary human G9 rotavirus strains

Of five globally important VP7 (G) serotypes (G1-4 and 9) of group A rotaviruses (the single most important etiologic agents of infantile diarrhea worldwide), G9 continues to attract considerable attention because of its unique natural history. Serotype G9 rotavirus was isolated from a child with diarrhea first in the United States in 1983 and subsequently in Japan in 1985. Curiously, soon after their detection, G9 rotaviruses were not detected for about a decade in both countries and then reemerged in both countries in the mid-1990s. Unexpectedly, however, such reemerged G9 strains were distinct genetically and molecularly from those isolated in the 1980s. Thus, the origin of the reemerged G9 viruses remains an enigma. Sequence analysis has demonstrated that the G9 rotavirus VP7 gene belongs to one of at least three phylogenetic lineages: lineage 1 (strains isolated in the 1980s in the United States and Japan), lineage 2 (strains first isolated in 1986 and exclusively in India thus far), and lineage 3 (strains that emerged/reemerged in the mid-1990s). Currently, lineage 3 G9 viruses are the most frequently detected G9 strains globally. We characterized a porcine rotavirus (A2 strain) isolated in the United States that was known to belong to the P[7] genotype but had not been serotyped by neutralization. The A2 strain was found to bear serotype G9 and P9 specificities as well as NSP4 [B] and subgroup I characteristics. By VP7-specific neutralization, the porcine G9 strain was more closely related to lineage 3 viruses than to lineage 1 or 2 viruses. Furthermore, by sequence analysis, the A2 VP7 was shown to belong to lineage 3 G9. These findings raise intriguing questions regarding possible explanations for the emergence of variations among the G9 strains.     

In Vitro and In Vivo Characterization of MEMS Microneedles

Transdermal drug delivery TDD systems have many advantages but are conventionally limited by the low permeability of skin. The idea of using microneedles to painlessly penetrate the topmost impermeable stratum corneum has previously been put forward. In this paper, the fabrication of solid and hollow silicon microneedles with straight side-walls and with the following dimensions: 20–100 m in diameter and 100–150 m in length is described. In vitro tests demonstrate that with prior solid microneedle application, transdermal drug transport is significantly increased by 10–20 times, with the degree of enhancement being related to needle diameter. In vivo tests in diabetic animals, however, were unable to demonstrate any delivery of insulin through the hollow microneedles. It is proposed that two factors, microneedle length and tip sharpness, have to be improved for systemic drug delivery to be seen in vivo.     

一种LDL吸附剂载体-聚丙烯酰胺微球的合成及应用

研究用于低密度脂蛋白 (L DL)吸附的聚丙烯酰胺微球载体的合成工艺、结构特性及吸附 L DL 的性能 ,为进一步研发 L DL 吸附剂载体提供实验依据。采用反相悬浮聚合法按一定的配方合成聚丙烯酰胺微球载体 ,通过扫描电镜、图像分析仪、X光小角散射等手段对其结构特性 (粒径、孔径等 )进行表征 ;同时在微球上固定丝氨酰 -天冬氨酰 -谷氨酸 (SDE)三肽配体制成 L DL 吸附剂 ,通过体外静态吸附对其吸附性能进行了初步研究。结果表明微球粒径为 14 2 .1μm,孔径为 119.8nm,符合作为 L DL 吸附载体的需要 ;在交联剂与单体总量一定的条件下 ,微球孔径随着交联剂用量的增加而减小 ;合成的聚丙烯酰胺微球对 L DL 的非特异性吸附很小 ,而在其上偶联配体制成吸附剂后 ,又表现出对 L DL 的特异性吸附。本实验合成的聚丙烯酰胺微球是一种有效的 L DL 吸附剂载体。     

Molecular characterization of the <Emphasis Type="Italic">env</Emphasis> gene from Brazilian field isolates of Bovine Leukemia Virus

Molecular characterization of Bovine leukemia virus (BLV) isolates from Brazil using the env gene sequences revealed a high conservation of this gene. In most cases the substitutions corresponded to silent transitions. In addition, cystein residues, potential glycosylation sites, neutralization domains and other critical residues involved with the envelope structural domains and viral infectivity were conserved. Most of the substitutions found in the aminoacid sequences of the gp51 protein were localized in the G and H epitopes. Using the SIFT software, it was predicted that they should not alter the protein functions. Phylogenetic analyses showed that partial or complete env gene sequences grouped in three or four phylogenetic clusters, respectively. The sequences from the Brazilian isolates had similar mutation rates as compared to samples from other countries, and belonged to at least two phylogenetic clusters.     

恒河猴骨髓间充质干细胞分离培养及其生长特性

采用密度梯度离心和贴壁筛选方法分离纯化了恒河猴骨髓间充质干细胞(mesenchymal stem cells from bone marrow of Rhesus monkey,RhBMSCs);通过表面抗原检测和核型分析对细胞进行了初步鉴定;通过生长曲线的绘制和细胞凋亡的检测探讨了细胞的生长特点。本实验获得的RhBMSCs形态以梭型为主,核型正常,CD29表达率为99.2%,CD34、CD45、HLA-DR表达率均低于3.2%,RhBMSCs表型符合间充质干细胞的特点,且纯度较高,细胞生长旺盛,但倍增时间有随传代数的增加而逐渐延长的趋势。本实验探讨了RhBMSCs的体外分离、扩增培养及鉴定的方法,并对其生长特点进行了初步观察,这不仅有助于进一步了解与之近似的人的骨髓间充质干细胞的相关特性,而且为以猕猴为对象的BMSC定向分化和组织修复等动物体内实验打下了基础。