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Coronary revascularization in the elderly with stable angina

Journal of Geriatric Cardiology 2015年第5期12卷 555-568页

作者： Kirill Lenarovich Kozlov aleksandr Andreevich Bogachev Laboratory of Age-Related Clinical Pathology Department of Clinical Gerontology and Geriatrics St. Petersburg Institute of Bioregulation and Gerontology Northwestern Branch Russian Academy of Medical Sciences Saint-Petersburg Russia Department of Cardiovascular Medicine Kirov Military Medical Academy Saint-Petersburg Russia

A proportion of elderly with coronary artery disease is rapidly growing. They have more severe coronary artery disease, therefore, derive more benefit fi＇om revascularization and have a greater need for it. The elderly is a heterogeneous group, but compared to the younger cohort, the choice of the optimal revascularization method is much more complicated among them. In recent decades, results has improved dramatically both in surgery and percutaneous coronary intervention （PCI）, even in very old persons. Despite the lack of evidence in elderly, it is obvious, that coronary artery bypass surgery （CABG） has a more pronounced effect on long-term survival in price of more strokes, while PCI is certainly less invasive. Age itself is not a criterion for the selection of treatment strategy, but the elderly are often more interested in quality of life and personal independence instead of longevity. This article discusses the factors that influence the choice of the revascularization method in the elderly with stable angina and presents a complex algorithm for making an individual risk-benefit profile. As a consequence the features of CABG and PCI in elderly patients are exposed. Emphasis is centered on the frailty and non-medical factors, including psychosocial, as essential components in making the decision of what strategy to choose. Good communication with the patients and giving them unbiased information is encouraged.

关键词： Angina Cardiopulmonary bypass Coronary artery disease Stents The elderly

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Investigation of the parameters of spiral pattern in galaxies:the arm width

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Research in Astronomy and Astrophysics 2020年第8期20卷 177-180页

作者： aleksandr Mosenkov Sergey Savchenko Alexander Marchuk Department for Management of Science and Technology Development Ton Duc Thang UniversityHo Chi Minh CityVietnam Faculty of Applied Sciences Ton Duc Thang UniversityHo Chi Minh CityVietnam Saint Petersburg State University Department of AstrophysicsSt.Petersburg198504 Russia Special Astrophysical Observatory Russian Academy of SciencesNizhnii Arkhyz369167 Russia

In this work,we determine the parameters of spiral structure for a sample of face-on spiral *** practice,the solution to this problem is a hard task because of the diversity of observed characteristics associated with spiral structure,such as the number of arms,their shape,arm contrast,*** study spiral structure in galaxies based on an analysis of photometric cuts perpendicular to the arm *** method is based on an approximation of these slices with an analytical function and derivation of the parameters of spiral structure(arm width,asymmetry,pitch angle)using the fitted parameters from this *** algorithm has been applied to a sample of 155 galaxies selected from the Sloan Digital Sky Survey in different *** this paper,we only consider the results on arm width:most spirals exhibit an increase in their width with galactocentric *** 14 per cent of galaxies in our sample show an opposite trend or have an almost constant arm width at all radii.

关键词： methods:data analysis techniques:photometric galaxies:structure

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Malignant biliary obstruction:From palliation to treatment

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World Journal of Gastrointestinal Oncology 2016年第6期8卷 498-508页

作者： Brian R Boulay aleksandr Birg Division of Gastroenterology and Hepatology Department of MedicineUniversity of Illinois Hospital and Health Sciences System Department of Medicine University of Illinois Hospital and Health Sciences System

Malignant obstruction of the bile duct from cholan-giocarcinoma,pancreatic adenocarcinoma,or other tumors is a common problem which may cause debilitating symptoms and increase the risk of subsequent *** optimal treatment-including the decision whether to treat prior to resection-depends on the type of malignancy,as well as the stage of *** biliary drainage is generally discouraged due to the risk of infectious complications,though some situations may *** who require neoadjuvant therapy will require decompression for the prolonged period until attempted surgical *** pancreatic cancer patients,self-expanding metallic stents are superior to plastic stents for achieving lasting decompression without stent *** cholangiocarcinoma patients,treatment with percutaneous methods or nasobiliary drainage may be superior to endoscopic stent placement,with less risk of infectious complications or *** patients of either malignancy who have advanced disease with palliative goals only,the choice of stent for endoscopic decompression depends on estimated survival,with plastic stents favored for survival of < 4 *** endoscopic techniques may actually extend stent patency and patient survival for these patients by achieving local control of the obstructing *** photodynamic therapy and radiofrequency ablation may play a role in extending survival of patients with malignant biliary obstruction.

关键词： Pancreatic neoplasms Cholangiocarcinoma Extrahepatic cholestasis Stents Catheter ablation

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丛式井平台设计及井丛分组优化

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石油勘探与开发 2019年第3期46卷 588-593页

作者： ABRAMOV aleksandr School of Engineering Edith Cowan University

改进并测试了包含30多个钻井工程参数的技术-经济模型,通过新开发的计算机程序列出平台上的井丛分组方式并计算其技术经济效益。针对含24口初始产油量不同的井的平台,研究分析了7种钻井方案,得出了3种折现率和5种产油量递减率条件下净现... 详细信息

改进并测试了包含30多个钻井工程参数的技术-经济模型,通过新开发的计算机程序列出平台上的井丛分组方式并计算其技术经济效益。针对含24口初始产油量不同的井的平台,研究分析了7种钻井方案,得出了3种折现率和5种产油量递减率条件下净现值(NPV)最优的分组方式。研究表明,针对井丛井数不等的井平台,可能只需对现有设计进行轻微调整(改变几个井丛的布局)就能得到最大净现值;相对净现值增幅与净现值的绝对值成反比;相比常规项目中具有相等井数的井丛,采用井丛井数不等的分组方式可以使NPV增幅达到1%,页岩地层开发项目NPV增幅可达2%或更多,边际油田项目增幅高达45%。

关键词：平台钻井丛式井平台井分组批量钻井井丛

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Generalized equation for calculating rock cutting efficiency by pulsed water jets

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第4期11卷 867-873页

作者： Andrey Polyakov aleksandr Zhabin Eugene Averin Aleksey Polyakov Department of Geotechnologies and Underground Construction Tula State UniversityTula300012Russia OOO Skuratovsky Experimental Plant Tula300911Russia OOO Industrial Safety Examination Tula300600Russia

One of the promising methods for rock cutting technology is the use of high-speed water *** order to improve the cutting capacity of water jets without increasing the hydraulic power of equipment,pulsed water jets are basically used to increase the rock cutting ***,there are no mature recommendations for selection of rational parameters,and the relationship between indicators of rock cutting efficiency and parameters of pulsed water jet is still not *** this context,we aimed at developing a generalized equation for calculating rock cutting efficiency,in which all the major parameters in consideration of rock cutting process are ***,a calibration of the rational parameters of rock cutting by pulsed water jets was *** results are likely helpful for increasing productivity and reducing energy consumption.

关键词： Pulsed water jets Rock cutting Water jet technology Generalized equation Depth of cut

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RED WoLF hybrid energy storage system: Algorithm case study and green competition between storage heaters and heat pump

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Energy and AI 2023年第4期14卷 383-397页

作者： Alexander Alexandrovich Shukhobodskiy aleksandr Zaitcev Giuseppe Colantuono School of Built Environment Engineering and ComputingLeeds Beckett UniversityLeedsLS13HEUK Watt Wolf Limited 188-192 CommonsideBatleyEnglandWF176EBUK

Green house gases reduction is critical in current climate emergency and was declared as major target by United *** manuscript proposes the progressive adaptive recursive multi threshold control strategy for hybrid energy storage system that combines thermal storage reservoirs,heat pumps,storage heaters,photovoltaic array and a *** newest control strategy is tested in numerical experiment against primal dual simplex optimisation method as benchmark and previous iterations of RED WoLF threshold *** proposed algorithm allows improvement in reduction of CO_(2) emissions by 9%comparatively to RED WoLF double threshold approach and by 26%comparatively to RED WoLF single threshold ***,the proposed technique is at least 100 times faster than linear optimisation,making the algorithm applicable to edge *** proposed method is later tested in numerical experiment on two measured datasets from Luxembourg school and office,equipped with batteries and ground source heat *** system allows the reduction of CO_(2) emission and improvement of self-consumption,size reduction of the photovoltaic array installed at the facilities by at least by half as well as substituting battery storage by thermal storage,reducing the initial investment to the ***,despite 3.6 times difference in efficiency between heat pumps and storage heaters,the system equipped with latter have potential to achieve similar performance in carbon reduction,suggesting that energy storage have more prominent carbon reduction effect,than the power consumption,making cheaper systems with storage heaters a possible alternative to heat pumps.

关键词： Hybrid energy storage Photovoltaic Artificial intelligence Green house gases Energy management

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Variable retention forestry in European boreal forests in Russia

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Ecological Processes 2019年第1期8卷 424-434页

作者： Ekaterina Shorohova Sergey Sinkevich aleksandr Kryshen Ilkka Vanha-Majamaa Forest Research Institute of the Karelian Research Centre of the Russian Academy of Sciences Pushkinskaya str.11Petrozavodsk 185910Russia Saint-Petersburg State Forest Technical University Institutsky str.5Saint Petersburg 194021Russia Natural Resources Institute Finland(Luke)Latokartanonkaari 9FI-00790 HelsinkiFinland

We explored whether,and to what extent,variable retention(VR)forestry has been applied in European boreal forests in northwestern *** survey revealed VR since *** 1910 and the 1960s,the statistics showing how much was retained are largely ***,for example,in the 1950s,on a large scale in the Republic of Karelia,up to 200-ha-sized harvesting areas,18–33%,were retention patches with a mean growing stock of 30–40m3 ha−*** the fellings defined as“incomplete clear fellings,”which were the most common final felling type at that time,11–40%of the growing stock was *** the 1960s and the early 1990s,with more efficient harvesting and skidding techniques,conventional clear fellings with a much lower amount of retention were *** about the regeneration of harvested areas gradually led to smaller(maximum 50 ha)harvesting areas and the increase of silvicultural *** now,to ensure natural regeneration,patches of understory and 20–25 seed trees(i.e.,ca.15–25m3)per ha have been left permanently in harvesting ***-scale retention for protecting ecosystem functions and biodiversity was legislated in 1978 by preserving key biotopes up to 1000 ha in *** 2001,promoted by forest certification,the key biotopes,such as paludified forest patches,buffers around water bodies,and habitats of red-listed species,have also been retained in harvesting areas,together with a dispersed retention of different *** estimates of the amount of key biotopes are largely ***,estimates of 1–13%in harvesting areas and 23%in whole managed landscapes have been *** applied during the last century has emulated natural disturbances and created diverse uneven-aged forest structures with high amounts of diverse coarse woody *** conclude that an analysis of past and current retention practices is essential for estimating the global role of Russian *** decisions on the general direction

关键词： Biological legacies Nature conservation Biodiversity Clear felling Key biotopes Coarse woody debris,Silviculture Dispersed and aggregated retention

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Energy efficiencies and CO_(2)emissions associated with lowtemperature separation technologies for the processing of formation fluid from the Achimov deposits

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Petroleum Research 2023年第3期8卷 413-423页

作者： Alexandra Saitova Sergey Strokin Falk Ahnert aleksandr Chepurnov Peter the Great St Petersburg Polytechnic University Politechnicheskaya str.29Saint Petersburg195251Russian Federation Wintershall Dea AG Friedrich-Ebert-Straße 160Kassel34119Germany Wintershall Dea Russia GmbH Reshetnikova str.14ASaint Petersburg196105Russian Federation

Three different technologies for the low-temperature separation(LTS)of gas condensate from the Achimov deposits in the Russian Urengoyskoe gas and condensate field were assessed using exergy *** options examined included turbo-expansion and *** exergy values were calculated for material streams and exergy losses and efficiencies were estimated for dedicated equipment used in the *** lowest exergy loss of 4221.2 kW was obtained using turboexpansion and electricity *** carbon release associated with each scenario was calculated while considering different production rates,technological parameters and natural decreases in wellhead *** integral carbon footprint after 40 years of LTS operation was estimated for all cases.A classical ejector-based LTS scheme was shown to produce 1200 t of CO_(2)emissions over 40 years of *** same scheme combined with a turboexpander and electricity generator produced 59%less CO_(2)in the same *** expansion-cogeneration LTS scheme was found to be the most effective and ecologically friendly among the various options based on this analysis.

关键词： Oil and gas field Gas condensate Carbon emission Carbon footprint Complex gas treatment unit

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Impact and Friction Sensitivity of Energetic Materials：Methodical Evaluation of Technological Safety Features

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火炸药学报 2015年第3期38卷 1-8页

作者： aleksandr Smirnov Oleg Voronko Boris Korsunsky Tatyana Pivina Bakhirev State Scientific Research Institute of Mechanical Engineering DzerzhinskNizhny Novgorod Region 606002Russia Institute of Problems of Chemical Physics Russian Academy of SciencesChernogolovkaMoscow Region142432Russia Zelinsky Institute of 0rganic Chemistry Russian Academy of SciencesMoscow119991Russia

Key methods developed and used in the USSR and in the Russian Federation to determine the impact and friction sensitivity of energetic materials and explosives have been *** methodologies and instruments that underlie the assessment of their production and handling safety have been *** of a large number of compounds have revealed relationships between their sensitivity parameters and structure of individual compounds and *** range of change of physical and chemical characteristics for the compounds we examined covers the entire region of their *** methodology and equations have been formulated to estimate the impact and friction sensitivity parameters of energetic materials and to evaluate the technological safety in *** developed methodology is characterized by high-accuracy calculations and prediction of sensitivity parameters.

关键词： energetic materials experimental testing friction sensitivity impact sensitivity regressive analysis safety in use methodical evaluation

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Optimal Design of Horizontal Stabilizer for a High-range Wide Body Airplane

Optimal Design of Horizontal Stabilizer for a High-range Wid...

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作者： Elkin aleksandr 上海交通大学

学位级别：硕士

在复合材料的优化设计中,世界各国的航天设计局都面临着一个重大的问题。大多数适用于金属结构的传统设计方法不适用于复合材料结构优化。因此,本文旨在发展新的适用于复合材料飞机结构的优化设计方法,并通过飞机水平尾翼这一飞机主结... 详细信息

在复合材料的优化设计中,世界各国的航天设计局都面临着一个重大的问题。大多数适用于金属结构的传统设计方法不适用于复合材料结构优化。因此,本文旨在发展新的适用于复合材料飞机结构的优化设计方法,并通过飞机水平尾翼这一飞机主结构来展示这个方法。本文研究的主要问题是在进行设计时应考虑哪些特征,并确保复合材料结构不会超重,以及应采取何种方法进行优化设计。即,优化设计被定义为结构的有效状态,飞机结构重量最小且满足所有强度要求和其他条件。本文通过文献调研,将经典层合板理论、梁理论和有限元方法,用于复合材料水平尾翼的优化设计。采用经典层合板理论和梁理论,可快速确定水平尾翼上剪切流的大小,并计算出所需的复合材料的铺层数量。为应用这些理论方法,本文采用MATLAB编写了相应的计算程序和优化算法以优化复合材料水平尾翼的厚度。此外,本文利用有限元软件ABAQUS建立复合材料水平尾翼的有限元模型,开发了相应的优化计算程序,获得了优化后机翼的厚度。综合应力及相关参数的分析表明,基于经典板理论和梁理论的复合材料构件的设计方法是可行的。水平尾翼在静态载荷作用下的有限元模型显示了与整个结构大致相同的应力。这意味着结构件已达到最佳状态。研究表明,本文提出的设计方法在水平尾翼等飞机部件的设计中具有一定的应用价值。基于经典复合材料板和梁理论法和有限元法各有利弊。第一种方法更计算效率高,对初步设计非常有用,但它过于简化,不能像有限元模型一样给出详细的应力分布。有限元计算精度好,但建立一个有限元模型和实现优化分析非常耗时,它用于详细设计阶段更适合。

关键词：飞机设计结构优化复合材料水平尾翼经典复合材料理论有限元法

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