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Functionalization of Silica Surface with UV-Active Molecules by Multivalent Organosilicon Spacer

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Open Journal of Inorganic Chemistry 2016年第3期6卷 163-174页

作者： Olga Iliashevsky elina Rubinov Yafa Yagen Moshe Gottlieb Chemical Engineering Department Ben Gurion University of the Negev Beersheva Israel

Immobilization of active molecules by attachment onto solid surfaces is a well-established practice in many processes and applications. Silica micro- and nano-particles are attractive candidates as support for active molecules as a result of a combination of desirable properties. The present study deals with grafting of a functional UV active molecule onto silica surfaces via hydrosilylation reactions using multivalent organosilicon spacers. Different types of organosilicon precursors based on dimethylsiloxysilanes containing multiple SiH groups were used as spacers between vinyl-modified silica surface and the benzotriazole UV-absorber (UVA). Firstly, the surface of silica was modified with vinyltrimetoxsisilane coupling agent. The UVA molecules were attached to the silica-vinyl by a two-step procedure involving hydrosilylation reaction. The successful grafting was confirmed by FTIR, TGA and UV-Vis characterization. More than fivefold increase in UVA loading was found for the MH30 multifunctional spacer, which contains approximately 75 SiH groups per molecule, when compared to a four-functional spacer. Furthermore a branched, bulky six-functional spacer is preferred over a linear spacer of the same functionality. UV activity of functionalized silica was studied by UV-Vis spectroscopy, indicating that the immobilization of UVA onto silica surface has not altered its UV absorbance properties.

关键词： Silica Functionalized Silica UV Absorbers Hydrosilylation Organosilicon

Probiotic Leuconostoc mesenteroides ssp. cremoris and Streptococcus thermophilus induce IL-12 and IFN-γ production

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World Journal of Gastroenterology 2008年第8期14卷 1192-1203页

作者： Riina A Kekkonen elina Kajasto Minja Miettinen Ville Veckman Riitta Korpela Ilkka Julkunen University of Helsinki Institute of Biomedicine Pharmacology PO Box 63 Helsinki 00014 Finland Valio Ltd Research Centre Meijeritie 4 00370 Helsinki Finland National Public Health Institute Department of Viral Diseases and Immunology Mannerheimintie 166 Helsinki 00300 Finland University of Helsinki Institute of Biomedicine Pharmacology PO Box 63 Helsinki 00014 Finland Foundation for Nutrition Research PO Box 30 Valio 00039 Finland Valio Ltd Research Centre Meijeritie 4 00370 Helsinki

AIM： To investigate the capacity of potentially probiotic strains from six bacterial genera to induce cytokine production alone or in combinations in order to identify potential enhancing or synergistic effects in order to select probiotic bacteria for in vivo purposes.METHODS： Cytokine production in human peripheral blood mononuclear cells （PBMC） in response to stimulation with eleven different potentially probiotic bacterial strains from Streptococcus, Lactobacillus, Bifidobacterium, Lactococcus, L euconostoc a n d Propionibacterium genera was analysed. Production and mRNA expression of TNF-α, IL-12, IFN-y and IL-10 were determined by ELISA and Northern blotting, respectively.RESULTS： All tested bacteria induced TNF-α production. The best inducers of Thl type cytokines IL-12 and IFN-y were Streptococcus and Leuconostoc strains. All BiHdobacterium and Propionibacterium strains induced higher IL-IO production than other studied bacteria. Stimulation of PBMC with any bacterial combinations did not result in enhanced cytokine production suggesting that different bacteria whether gram-positive or gram- negative compete with each other during host cell interactions.CONCLUSION： The probiotic S. thermophilus and Leuconostoc strains are more potent inducers of Thl type cytokines IL-12 and IFN-γ than the probiotic Lactobacillus strains. Bacterial combinations did not result in enhanced cytokine production.

关键词： Probiotics Streptococcus Lactobacillus Bifidobacterium lactococcus leuconostoc Propionibacterium Immune response Cytokines Mononuclear cells

Optimisation of extrusion cooking conditions and characterization of rice (Oryza sativa)—Sweet potato (Ipomoea batatas) and rice-yam (Dioscorea alata) based RTE products

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Agricultural Sciences 2013年第9期4卷 12-22页

作者： elina Brahma Hazarika Anjan Borah Charu Lata Mahanta Department of Food Engineering and Technology School of Engineering Tezpur University Assam India

Extrusion cooking has been extensively used toproduce variety of foods like ready to eatbreakfast cereals, baby foods, snack foods, etc. Taking rice flour as the base ingredient, two locally available tuberous root vegetables, greater yam(Dioscoreaalata) and sweet potato (Ipomoeabatatas) were used in this study for the development of ready-to-eat breakfast products in asingle screw extruder. During extrusion cooking, the screw speeds ranged from 132 to 468 rpm and the barrel temperatures ranged from 103°C to 137°C. The extrudates were then analyzed for various physical and physicochemical properties. Optimization was done following ResponseSurface Methodology (RSM) using CentralComposite Design. Using screw speed, barrel temperature and feed composition as the three independent variables, the three responses taken were bulk density, expansion index and breaking strength. The optimized conditions wereused for developing 3 new products one of which alsocontained tomato pulp powder. The productswere analyzed for their physical, proximate, sensoryand antioxidant properties. There was significantcolour change in all the three samples as indicated by total colour change (ΔE). Texture analysis of the extrudate samples showed hardness values ranging from 28.68 N to 47.57 N. Amylose content was found to be 15.3% in rice-sweet potato extrudate, 14.7% in rice-yam extrudate and 18.2% in rice-sweet potato-tomato extrudate. The antioxidant profile of the extrudates studiedthrough DPPH (2,2-diphenyl-picryhydrazyl)scavenging activity and FRAP (ferric reducing antioxidant property) showed that the antioxidant capacity in all the 3 extrudates was very low. Rice flour incorporated with sweet potato wasjudged the best on sensory evaluation. Thestudy has shown that both sweet potato and greater yam tubers can be commercially exploited for the development of ready-to-eat (RTE) products.

关键词： Extrusion RSM RTE Physicochemical Properties

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阿根廷本土汉语初级学生介词习得研究

阿根廷本土汉语初级学生介词习得研究

作者： REYES MARIA elina（玛利亚）吉林大学

学位级别：硕士

近年来,中国的国际影响力日益增强,与世界多个国家建立了密切的经济与民间往来。交往的过程势必需要大量同时精通两国语言的相关人才,很多国家都掀起了汉语学习浪潮。这股热潮也吹到了遥远的阿根廷,近年来阿根廷本土汉语学习人数众多且... 详细信息

近年来,中国的国际影响力日益增强,与世界多个国家建立了密切的经济与民间往来。交往的过程势必需要大量同时精通两国语言的相关人才,很多国家都掀起了汉语学习浪潮。这股热潮也吹到了遥远的阿根廷,近年来阿根廷本土汉语学习人数众多且热情高涨,阿根廷本土汉语教学水平也有了相当程度的提高。任何一种第二语言的学习都会遇到这样或那样的问题,本土语言学习者因为缺乏第二语言的使用环境,会比在中国学习汉语的学习者遇到更多的困难。笔者通过研究发现,阿根廷许多初级学习者在汉语学习过程中,会出现许多偏误,尤其是汉语的介词学习。在实际交流过程中,汉语介词的使用频率非常高,它是很多句式的重要组成部分。然而,一直以来对西班牙语学生的初级介词习得问题的研究并不多,对阿根廷本土学生的介词习得研究更是空白。为了解决这一学科信息匮乏的问题,笔者对阿根廷主要汉语教学机构的阿根廷初级学生汉语介词习得进行了研究。通过对阿根廷初级汉语学生的问卷调查,重点分析了他们关于汉语介词“在、跟、对、向”的习得情况,从问卷结果和学生平时专向练习中,分析了产生偏误的原因,提出了提高阿根廷教育质量的教学策略。本文分为五章。在第一章中,笔者阐述了本文的研究目的及价值。笔者还详细介绍了之前其他学者对拉丁美洲学生介词习得问题的研究情况以及对阿根廷汉语教学机构的研究。第二章阐述了介词“在、跟、对、向”在西班牙语中的相应表达对比。第三章阐述了阿根廷汉语教育的现状。此外,还解释了调查问卷的设计目的、设计方案、调查对象和调查结果。第四章分析了阿根廷大学生在介词使用中出现的偏误(顺序偏误、冗余和遗漏),提出了造成这些偏误的原因:母语(西班牙语)负迁移、所学语言(汉语)局限性、教材及教学不足。第五章提出了帮助学生克服偏误的教学策略。希望本文能对其他学者的研究工作有所补充,有助于阿根廷等拉美国家汉语教育的发展。

关键词：介词阿根廷学生教育偏误分析语言习得

Oxidative Stress and Post-Ischemic Inflammatory Response in Ischemic Stroke Complicated with Diabetes Mellitus Type 2

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Journal of Biosciences and Medicines 2015年第3期3卷 94-98页

作者： Gohar Tsakanova elina Arakelova Armine Soghoyan Violetta Ayvazyan Institute of Molecular Biology NAS RA Armenia “Surb Grigor Lusavorich” Medical Center CJSC Armenia

Oxidative stress and post-ischemic inflammatory response are the key pathogenic mechanisms of the neuronal injury caused by ischemic stroke (IS). On the other hand, Diabetes is a major risk factor for the development of stroke, increasing the susceptibility to atherosclerosis and the prevalence of atherogenic risk factors, including hypertension, obesity, and abnormal blood lipids. The aim of current study was to analyze the functional activity of oxidant-antioxidant system and post-ischemic inflammatory response in IS patients complicated and noncomplicated with diabetes mellitus type 2 (DM2). ELISA, photochemiluminescent and spectrophotometric methods were used to analyze the serum samples of IS patients complicated and noncomplicated with DM2, DM2 patients, as well as healthy subjects. The results obtained suggest that IS complicated with diabetes is characterized by higher intensity of the lipid peroxidation process as compared to IS noncomplicated with diabetes that, probably, is one of the determining factors responsible for more severe clinical course of IS patients complicated with DM2 compared to those noncomplicated with DM2. It is also shown that mechanisms of the compensatory response to oxidative stress on the level of antioxidants in IS patients complicated with diabetes differ from those detected in IS noncomplicated with diabetes. A significant increase of the levels of the five analyzed cytokines in both groups of IS patients were detected. Based on the results obtained we suggest that metabolic, molecular, and cellular level alterations are typical for long-term DM2 impair compensatory mechanisms protecting the body from oxidative stress, and that in IS complicated with DM2 the systemic inflammatory reactions and oxidative stress are more intense than in case of IS noncomplicated with DM2.

关键词： Oxidative Stress Postischemic Inflammatory Response Cytokines Ischemic Stroke Diabetes Mellitus

Cervico-Facial Soft Tissue Emphysema with Pneumo-Mediastinum Following Endoscopic Sinus Surgery: A Dilemma of Related or Unrelated Complication

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International Journal of Otolaryngology and Head & Neck Surgery 2013年第3期2卷 86-89页

作者： Produl Hazarika Seema elina Punnoose Ananth Pai Rajeev Chaturvedi Department of ENT NMC Specialty Hospital Abu Dhabi UAE Department of General Surgery NMC Specialty Hospital Abu Dhabi UAE Department of Radiology NMC Specialty Hospital Abu Dhabi UAE

We present a rare and unusual complication of cervico-facial soft tissue emphysema with pneumo-mediastinum which occurred in a 30-year-old female Jordanian patient in our hospital in October 2010 in Abu Dhabi following FESS. CT scan evaluation of aero-digestive tract in the immediate post-operative period was done to ascertain the cause pertaining to any surgical trauma or anaesthesia related complications. Such a case previously unreported has been included in this study. A simple close monitoring after establishing the cause is usually sufficient in management of such related or unrelated complications during FESS which in our case was likely to be anaesthesia related. Published data of such a complication assists in building up a good and effective medical audit based on ethical practice. This paper stresses the importance of immediate CT scan of aero-digestive tract in evaluating the cause.

关键词： Endoscopic Sinus Surgery Cervico-Facial Emphysema Pneumo-Mediastinum Ethical Practice Medical Audit Extended Indication of Endoscopic Sinus Surgery CT Scan

(2-Hydroxyethyl)ammonium Lactates—Highly Biodegradable and Essentially Non-Toxic Ionic Liquids

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Green and Sustainable Chemistry 2011年第3期1卷 103-110页

作者： Sanita Pavlovica Andris Zicmanis elina Gzibovska Maris Klavins Peteris Mekss 不详

(2-Hydroxyethyl)ammonium lactates have been prepared by reactions of the corresponding (2-hydroxyethyl) amines with lactic acid and characterized by their 1H NMR, IR, and mass spectra. They have been quantita- tively analyzed by HPLC, and their water contents have been determined by the Karl-Fischer method. The title salts are low-melting solids or viscous liquids, and they belong to the class of polar, hydrophilic ionic liquids. The toxicity and chemical and biological degradation of the synthesized ionic liquids have been evaluated by methods described in European Standards. The measurements showed these ionic liquids to be highly biodegradable and only slightly toxic substances. Condensation reactions of benzaldehyde with ethyl cyanoacetate and with acetophenone have been performed in these materials as solvents. The possibility of simultaneously applying these ionic liquids as both solvents and catalysts for the mentioned reactions has been demonstrated, as well as repeated use of the same ionic liquid for a number of condensation reactions without any purification.

关键词： Ionic Liquids Biodegradation Toxicity Polarity Condensation Reactions

Lymphoepithelioma-Like Carcinoma of Parapharyngeal Space—A Case Report with Review of Literature

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International Journal of Otolaryngology and Head & Neck Surgery 2015年第2期4卷 163-168页

作者： Produl Hazarika Seema elina Punnoose John Victor Sreekala Nirmali Dutta Department of ENT NMC Specialty Hospital Abu Dhabi UAE Department of Pathology NMC Specialty Hospital Abu Dhabi UAE Department of Radiology NMC Specialty Hospital Abu Dhabi UAE

Extra-nasopharyngeal lymphoepithelioma-like carcinomas (LELC) are uncommon epithelial tumors. A few isolated case reports and series are available in literature involving the larynx, pharynx, salivary gland, lung etc., but involvement in the parapharyngeal space has not yet been reported. We aim to highlight one such case that has a clinical and radiological characteristic of a benign lesion whilst the histopathology reveals an infiltrating neoplasm. The typical clinical aggressiveness of a classical LELC of extra-nasopharyngeal lesion as described in literature is not present in our case. Also seen is an uncommon finding of abnormal branching of left external carotid artery. There is no standard treatment protocol for such a tumor;however, wide excision of this tumor in the parapharyngeal space via trans-cervical, trans-mandibular, trans-palatal approach has shown good and satisfactory tumor control of the primary site so far.

关键词： Lymphoepithelioma-Like Carcinoma (LELC) Parapharyngeal Space Trans-Cervical Trans-Mandibular Cells in Cords Lymphoplasmacytoid

The Use of Macroarray as a Simple Tool to Follow the Metabolic Profile of Lactobacillus plantarum during Fermentation

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Advances in Microbiology 2014年第14期4卷 996-1016页

作者： Minna Kahala Virpi Ahola elina Makimattila Lars Paulin Vesa Joutsjoki Biotechnology and Food Research MTT Agrifood Research FinlandJokioinenFinland Department of Biosciences University of HelsinkiHelsinkiFinland Institute of Biotechnology University of HelsinkiHelsinkiFinland

This study focused on defining the differences in L. plantarum gene expression levels in different media and in different growth phases using an easy and cost-efficient monitoring of gene expression. A macroarray based on a group of selected L. plantarum genes, 178 genes belonging to 18 main groups, printed onto a nitrocellulose filter was designed in this work. Using the macrofilters designed, the expression of a selected set of L. plantarum genes was assayed in synthetic MRS medium and in extracted carrot juice. To compare the potential differences of starter gene expression in hygienic and contaminated cultivation media, the L. plantarum strain was cultivated in both sterile and contaminated (yeast and Escherichia coli) MRS and carrot juice. The number of genes found to be regulated as a function of growth was clearly higher in MRS-based growth medium than in carrot juice, In carrot juice, expression of the gene encoding malolactic enzyme (MLE), which makes L. plantarum an advantageous microbe in e.g. wine making, was found to be upregulated in logarithmic phase of growth. The current study demonstrated that macroarrays printed on nitrocellulose filters with simple robotic systems can be analyzed by standard laboratory equipment and methods usually available in molecular laboratories. Using this technology, rapid and cost-efficient analysis of genome function of L. plantarum can be carried out e.g. in developing regions, where lactic acid fermentation of food and feed matrices is a common practice.

关键词： Macroarray Gene Expression L. plantarum