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Zingiber officinale extends Drosophila melanogaster life span in xenobiotic-induced oxidative stress conditions

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Frontiers in Biology 2018年第2期13卷 130-136页

作者： volodymyr Padalko Viktoriya Dzyuba Olena Kozlova Hanna Sheremet Olena Protsenko School of Medicine V.N. Karazin Kharkiv National University 4 Svobody Sq. Kharkiv 61022 Ukraine Department of Membrane Biophysics Research Institute of Biology V.N. Karazin Kharkiv National University 4 Svobody Sq. Kharkiv61022 Ukraine

BACKGROUND： The possibility of dietary ginger to enhance oxidative stress resistance and to extend life span was studied on Drosophila melanogaster. METHODS： Oxidative stress was induced by a reducing agent dithiothreitol. Experimental groups of male D. melanogaster were cultured on media containing： 1） no additive; 2） dithiothreitol, added into the nutritional mixture to the final concentration of 10 mM; 3） 25 mg of ginger powder g^-1 of the nutritional mixture; and 4） 10 mM ofdithiothreitol and 25 mg of ginger powder g l of the nutritional mixture. The number of alive fruit flies was inspected daily, and mean life span was determined for each experimental group. RESULTS： The addition of dithiothreitol to D. melanogaster nutritional mixture was established to result in an increase in concentration of two markers of oxidative stress conditions （thiobarbituric acid reactive substances as products of lipid peroxidation and carbonylated proteins as products of protein oxidation） in fly tissues. It was followed by significant reduction of mean life span and maximum life span of the last 10% of flies. Plant preparation, being added simultaneously with dithiothreitol, significantly diminished the negative effects of this xenobiotic. In conditions of additional stress load induced by hydrogen peroxide or high temperature, survival of insects treated with dithiothreitol on the background of ginger powder was the highest. CONCLUSIONS： Thus, the presented data give the evidence that ginger preparations can reduce oxidative stress outcomes and significantly increase the life expectancy of fruit flies in stress conditions.

关键词： ginger oxidative stress Drosophila melanogaster

Use of Twitter in disaster rescue: lessons learned from Hurricane Harvey

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International Journal of Digital Earth 2020年第12期13卷 1454-1466页

作者： volodymyr V.Mihunov Nina S.N.Lam Lei Zou Zheye Wang Kejin Wang Department of Environmental Sciences Louisiana State UniversityBaton RougeLAUSA Department of Geography Texas A&M UniversityCollege StationTXUSA

Despite the increasingly prominent role of social media in disaster events,studies analyzing its use in rescue operations remain *** Harvey hit Texas with unprecedented rainfall and flooding in 2017 and was marked by widespread use of social media for rescue *** conducted a survey of 195 Twitter users in Houston and surrounding communities who had requested for rescue during *** objective was to investigate our targeted group’s socioeconomic and flood exposure characteristics,report the effectiveness of Twitter,and highlight lessons learnt and suggestions made for its use in future rescue *** revealed that those requesting rescue on Twitter were better educated,employed(80%),and homeowners(81%).Majority of them were flooded(87%),but remained satisfied with current location and did not consider *** relatives and friends for rescue was most responsive and yielded higher assistance-provided rate than using *** respondents found Twitter helpful,but identified issues such as not knowing when volunteers received their requests or whether they would send *** suggested promoting Twitter accounts and hashtags that accept emergency *** study provides baseline information and actionable suggestions for first responders,community managers,and resilience practitioners to improve future rescue missions.

关键词： Twitter social media Hurricane Harvey flooding rescue online survey

Phenomena at three-phase electroslag remelting

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China Foundry 2021年第6期18卷 557-564页

作者： Zhong-li Liu Lev Medovar Ganna Stovpchenko volodymyr Petrenko Artem Sybir Yev.Volchenkov Yantai University Yantai 264005ShandongChina E.O.Paton Electric Welding Institute Kyiv 03180Ukraine National metallurgical academy of Ukraine Dnipro 49600Ukraine

The electroslag remelting(ESR)process is widely used to produce high-quality ingots and billets for high-alloyed steels and *** the single-phase and three-phase alternating current diagram with bifilar and monofilar connection are in use for heavy ingot *** numerical simulation of the three-phase bifilar circuit for the 120 t three-phase bifilar six-electrode ESR furnace at different variants of electric connection was presented and *** the bifilar diagram of power supply,the geometrical location of electrodes in a mould holds critical importance for performances:the close location of bifilar pair electrodes provides the highest heat productivity,but the equidistant location of electrodes gives a much more uniform heat *** monofilar mulit-electrode diagram of three-phase connection without phase shift shows the most uniform distribution of potential and heat generation as well as a favorable magnetic field that makes this kind the most promising for providing a high quality of heavy ingots.

关键词： electroslag remelting three-phase circuit bifilar monofilar simulation heavy ingot

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壳聚糖改性及改性壳聚糖应用研究进展

济南大学学报（自然科学版） 2023年第1期37卷 84-93页

作者：汤薇董静赵金荣 volodymyr BESSARABOV 蒋晓杰杨效登齐鲁工业大学(山东省科学院)化学与化工学院山东济南250353 火箭军士官学校山东潍坊262500 基辅国立工艺设计大学基辅01011乌克兰绍兴职业技术学院建筑与设计艺术学院浙江绍兴312000

针对壳聚糖产量多、可再生和性能优良的性质,但因只溶于酸性溶液而应用范围受限的不足,综述壳聚糖的改性方法和亲水改性壳聚糖、疏水改性壳聚糖的应用,包括酰基化改性、羧基化改性、季铵化改性、羟基化改性和烷基化改性;根据改性壳聚糖... 详细信息

针对壳聚糖产量多、可再生和性能优良的性质,但因只溶于酸性溶液而应用范围受限的不足,综述壳聚糖的改性方法和亲水改性壳聚糖、疏水改性壳聚糖的应用,包括酰基化改性、羧基化改性、季铵化改性、羟基化改性和烷基化改性;根据改性壳聚糖的特点和性质,介绍亲水改性壳聚糖和疏水改性壳聚糖在食品添加和包装、药品包装、活性成分包载与释放、皮革涂饰和工业废水处理领域的应用研究和成果,指出壳聚糖作为一种重要的生物多糖,未来的研究重点是开拓壳聚糖基材料在医疗器械、药物包载与靶向传递、绿色包装材料的应用范围,积极配合国家碳达峰、碳中和战略。

关键词：壳聚糖改性性质应用

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Kidding after Transfer of in Vitro Produced Saanen Goat Embryos into Local Ukrainian Breed Recipients in Different Seasons

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Open Journal of Ecology 2023年第8期13卷 549-559页

作者： Anastasiia Bogdaniuk volodymyr Garkavii Oleg Berestovoyy Vasyl Tsvyk Narhiz Yusifli Oleh Sigunov Olga Kramareva Maryna Petrushko LLC “Institute of Contemporary Veterinary Technologies” Cherevky Ukraine Department for Cryobiology of the Reproductive System Institute for Problems of Cryobiology and Cryomedicine of National Academy of Science of Ukraine Kharkiv Ukraine Farm “Tatyana 2011” Cherevky Ukraine

In recent years, the demand for goat products has been growing due to the fact that goat milk has a number of advantages over cow milk, for example, it is low in lactose, and is considered less allergenic and easier to digest. To increase production during both breeding and non-breeding seasons and reduce the price of dairy products, it is necessary to effectively use reproductive management and assisted reproductive technologies. In vitro embryo production makes it possible to obtain a large number of eggs from goats, which for some reason are unable to conceive, but have genetic value. Afterward in vitro produced embryos can be transferred into recipient goats of other less genetically valuable breeds, such as the Ukrainian local breed. Therefore, the aim of the present study was to investigate the effectiveness of transfers of in vitro produced embryos of Saanen goats into surrogate sires of the Ukrainian local breed in different seasons. All manipulations with animals were carried out following ethical standards (Strasbourg, 1986). Six Saanen goats were selected as the oocyte donors. After the hormonal stimulation oocytes were retrieved by laparoscopic ovum pick-up. In vitro produced embryos were transferred laparotomically into 24 recipients of Ukrainian local breed. Fifty days after embryo transfers, pregnancies were determined by ultrasound diagnostics. Although the embryo development rate in the breeding season was 20% higher than in the non-breeding season, there was no difference in pregnancy and kidding rates between seasons. In conclusion, the transfer of in vitro produced Saanen goat embryos to recipients of the Ukrainian local breed gives the opportunity to achieve pregnancy and kidding regardless of the breeding season, which will enable a faster and more efficient increase in the livestock of highly productive goats in Ukraine in the post-war period.

关键词： Goats in Vitro Produced Embryos Saanen Breed Goat Reproduction Embryo Transfer Kidding Rate Breeding Season

基于前体聚合状态对碳材料进行分类以发展结构-性质关系(英文)

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催化学报 2014年第6期35卷 778-782页

作者： Oleksiy V.Khavryuchenko volodymyr D.Khavryuchenko Chemistry Department Taras Shevchenko National University of KyivVolodymyrska str.64 Kyiv 01601 Ukraine CompChem Group Revutskogo str.13 Kyiv 02091 Ukraine

Modern carbon science lacks an efficient structure-related classification of materials. We present an approach based on dividing carbon materials by the aggregate state of the precursor. The common features in the structure of carbon particles that allow putting them into a group are discussed, with particular attention to the potential energy stored in the carbon structure from different rates of relaxation during the synthesis and prearrangement of structural motifs due to the effect of the precursor structure.

关键词：结构特性碳材料聚合状态分类前体结构相关耳鼻喉科聚集态

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Management of residual penile curvature after penile prosthesis placement

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Asian Journal of Andrology 2021年第2期23卷 129-134页

作者： Denis V Krakhotkin David J Ralph Gideon A Blecher volodymyr A Chernylovskyi Francesco Greco Evgeny E Bakurov Ruslan A Bugaev Central District Hospital Outpatient DepartmentKamenolomniRostov Region 346480Russia University College London St Peter’s Andrology Centre and University College London Hospitals London W1G 6BJUnited Kingdom Monash University Department of SurgeryMelbourne 3168Australia The Alfred Hospital Department of UrologyMelbourne 3004Australia Department of Urology 1 City Clinical Hospital No.4Dnipro 49102Ukraine Department of Urology Humanitas GavazzeniBergamo 24125Italy Department of Surgery No.1 Rostov Regional Hospital ROKB 1Rostov-on-Don 344015Russia

Residual penile curvature is a common situation following the implantation of a penile prosthesis in patients with Peyronie’s ***,there is a variety of options for the correction of residual curvature,including penile modeling,plication techniques,as well as tunical incision/excision with or without grafting.A literature search of PubMed and Medline databases was conducted from 1964 until 2020,using search terms for all articles in the English *** this article,we provide a review of the techniques and the outcomes,according to the published literature.

关键词： grafting modeling penile curvature penile implant penile prosthesis Peyronie’s disease tunical plication

Genes of tumor necrosis factors and their receptors and the primary open angle glaucoma in the population of Central Russia

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International Journal of Ophthalmology(English edition) 2017年第10期10卷 1490-1494页

作者： Evgeniya Tikunova Veronika Ovtcharova Evgeny Reshetnikov volodymyr Dvornyk Alexey Polonikov Olga Bushueva Mikhail Churnosov Department of Medical Biological Disciplines Belgorod State University School of Biological Sciences University of Hong Kong Department of Biology Medical Genetics and EcologyKursk State Medical University

AIM：To examine the association of genetic polymorphisms（-308）G/A TNFα,（＋250）A/G Ltα,（＋36）A/G TNFR1,（＋1663）A/G TNFR2 with the development of primary open angle glaucoma（POAG）among people in Central ***：The study sample included 443 individuals,of which 252 patients with POAG and 191 individuals in the control *** of（-308）G/A TNFα,（＋250）A/G Ltα,（＋36）A/G TNFR1,（＋1663）A/G TNFR2 was performed using polymerase chain *** distribution of alleles and genotypes of the studied DNA markers in the groups was examined by 2×2 contingency tables andχ2with the Yates’s correction for continuity and odds ratios（OR）with95%confidence intervals（CI）.RESULTS：Allele（-308）G TNFα（Р=0.01,OR=1.78,95%CI1.12-2.85）was identified as a risk factor for ***（-308）AA TNFαare at a lowest risk for development of the disease（Р=0.01,OR=0.0005）.The following combination of genetic variants of cytokines were associated with a reduced risk of POAG：（＋1663）A TNFR2 and（＋250）G Ltα（OR=0.34）CONCLUSION：Genetic polymorphisms（-308）G/A TNFα,（＋250）A/G Ltα,（＋1663）A/G TNFR2 associated with the development of POAG in the population of Central Russia.

关键词： primary open angle glaucoma tumor necrosisfactor tumor necrosis factor receptor gene polymorphism

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自旋催化剂——量子触发化学反应（英文）

催化学报 2015年第10期36卷 1656-1661页

作者： Oleksiy V.Khavryuchenko volodymyr D.Khavryuchenko 苏党生计算化学集团乌克兰基辅UA-02091 中国科学院金属研究所沈阳材料科学国家(联合)实验室辽宁沈阳110016 马克斯普朗克协会弗里茨·哈伯研究所无机化学系德国柏林Faradayweg 4-6 D-14195

当初始态和过渡态之间存在能量差时,通常会考虑用催化的方法来增加反应速率,即经由能量更低过渡态的反应路径,或增加反应物初始态能量,如改变溶剂或在特殊表面吸附分子.然而,对于某些类型的反应,如H2和O2反应生成水,NO的氧化等,仅仅采... 详细信息

当初始态和过渡态之间存在能量差时,通常会考虑用催化的方法来增加反应速率,即经由能量更低过渡态的反应路径,或增加反应物初始态能量,如改变溶剂或在特殊表面吸附分子.然而,对于某些类型的反应,如H2和O2反应生成水,NO的氧化等,仅仅采用这些方法还不够,因为反应物和产物具有不同的自旋态,而自旋守恒定律一般会禁止该过程的发生.即使克服了能垒,该体系也不能转化成稳定的产物,且不改变其电子自旋多重态.但在特殊的非热力学条件下,该类反应仍可发生.这通常指自旋不守恒的过程.改变体系电子自旋最直接的方法是与原子核自旋有作用的电子自旋翻转.它可由自旋-轨道耦合来实现,因此,其实现的几率取决于元素的原子数.从3d金属开始,发生这种情况的可能性甚至更大.这是由于与d轨道耦合的效率更高所致,所以采用自旋交叉就能方便地解释自旋禁止反应发生的原因.然而,轻原子发生自旋翻转的可能性很低,因此,当面对无金属化学时,我们应该考虑自旋禁止反应发生的第二个方法—自旋催化.通过帮助克服自旋禁止的物质以促进化学反应,或通过顺磁催化剂诱导自旋解耦以降低活化能垒,这类现象就可定义为自旋催化.简而言之,为了得到想要的和热力学更有利的自旋态,一个反应粒子可以与自旋催化剂交换磁矩;该自旋催化剂需有拟自旋-简并基态或低激发态.因此,体系整个的自旋仍守恒,但可发生反应.值得强调的是,自旋"催化剂"指的是分子状态和固体状态,通常后者应用于工业中则方便得多.自旋催化是作为自旋化学的范例来研究的,或在外磁场中化学诱导动态核极化和反应,主要是指采用EPR光谱研究以液相为主的过程.本文简略介绍了自旋催化的理论.实际上,自旋催化与常规催化之间并不相互抵触—相同的材料既可作为自旋催化剂,也可用作常规催化剂,都起着降低反应能垒和提供自旋交换的自由基中心的作用.另外,许多现代材料包含着常规催化剂和自旋催化剂的特性.有些发生在多核磁性金属中心上的过程可能本身就包含着常规催化(活化底物)、自旋交叉(与d金属相互作用)和自旋催化(金属-氧簇合物中低能的铁磁-反铁磁转化)效应.气相自旋催化在实际应用中产生的主要问题是在稀释的体系中三粒子碰撞几率低,常规催化在这方面则有很多优势.我们首先列出固体成为自旋催化剂的条件:(1)活性中心中至少2个自旋态的能量差要小于反应温度下热运动的能量,这样无需额外的能量活化催化剂;(2)较大的比表面积以提供更多的自旋中心用于相互作用;(3)最好能够自旋导电,在此情况下反应无需三粒子碰撞即可发生.这是因为自由基可通过催化剂的电子系统交换自旋,使得自旋-自旋相互作用的几率迅速增加,从而有利于自旋催化反应的进行.另外,如果固体或载体具有自旋导电性,则无需外加电场或磁场,即有可能遥控催化中心的电荷和自旋态,从而避免使用外电场或磁场.实际上,许多反应过程本身就包含着自旋催化,它还可使反应过程的许多不足变成优势,如对于不需要的链式自由基反应;通过引入自旋捕获剂使得自旋禁止反应成为有用的自旋催化;磁性粒子的浓度以及外加磁场和电场均可导致自旋催化/禁止反应.由于均相自旋催化的研究较早,在此不再赘述.本文详细介绍了多相体系中的自旋催化的应用,如燃烧、温和氧化、环化、开环、非极性小分子的活化和不稳定自由基的耦合等.可能用作自旋催化剂的材料有:含有不同顺磁性的金属离子的磁性氧化物或多核磁性簇合物;嫁接在一些载体上的多核络合物或过渡金属(低温催化);带有非整数氧化价态的导电金属;各种具有半金属性和导电性的碳材料.研究自旋催化反应的一个突出问题就是这些过程大部分是自由基式的,趋于非线性区域,因而很难预测,也没有一个便利的工具用以描述,甚至预测自旋催化反应,但也许这些研究的特点就是不可预测性.自旋催化除了可调变反应的进行,我们还可从中获得一个独特的调节手段:通过外加磁场或电场触发基元过程,在非热力学上控制反应的进行.该手段在控制化学反应方面具有明显优势,因为现在大都是通过调节温度、压力和流量等参数来实现对化学反应的控制,且滞后严重.同时,通过添加外加磁场可立刻改变反应速率.另外,通过降温可精细控制基元反应,从而开辟了一种抑制副反应的方法,因而也使得反应的随机性降低.

关键词：催化自旋化学化学键均裂氧化过程自由基耦合

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