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New perspectives on robotic pancreaticoduodenectomy:An analysis of the National Cancer Database

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World Journal of Gastrointestinal Surgery 2023年第1期15卷 60-71页

作者： aleksandr Kalabin Vishnu R Mani Robin L Kruse Chase Schlesselman Kai Yu Li Kevin F Staveley-O'Carroll Eric T Kimchi Department of Surgery University of MissouriColumbiaMO 65212United States Department of Surgery The Johns Hopkins HospitalBaltimoreMD 21287United States

BACKGROUND Pancreatic ductal adenocarcinoma is a common *** all advancements,the prognosis remains,poor with an overall 5-year survival of only 10.8%.Recently,a robotic platform has become an attractive tool for treating pancreatic cancer(PC).While recent studies indicated improved lymph node(LN)harvest during robotic pancreaticoduodenectomy(PD),data on long-term outcomes are *** To evaluate absolute LN harvest during *** outcomes included evaluating the association between LN harvest and short-and long-term oncological outcomes for three different surgical *** We conducted an analysis of the National Cancer Database,including patients diagnosed with PC who underwent open,laparoscopic,or robotic PD in ***-way analysis of variance was used to compare continuous variables,chi-square test-for *** survival was defined as the time between surgery and *** survival time was estimated with the Kaplan-Meier method,and groups were compared with the Wilcoxon test.A Cox proportional hazards model was used to assess the association of covariates with survival after controlling for patient characteristics and procedure *** 17169 patients were included,8859(52%)males;mean age 65;14509(85%)white.13816(80.5%)patients had an open PD,2677(15.6%)and 676(3.9%)-laparoscopic and robotic PD *** comorbidity index(Charlson-Deyo Score)*** average,18.84 LNs were *** LN harvest during open,laparoscopic and robotic PD was 18.59,19.65 and 20.70 respectively(P<0.001).On average 2.49 LNs were positive for cancer and did not differ by the procedure type(P=0.26).Vascular invasion was noted in 42.6%of LNs and did differ by the approach:42.1%for open,44.0%for laparoscopic and 47.2%for robotic PD(P=0.015).Median survival for open PD was 26.1 mo,laparoscopic-27.2 mo,robotic-29.1 mo(P=0.064).Survival was associated with higher LN harvest,while higher number of positive LNs was assoc

关键词： Pancreatic cancer Pancreaticoduodenectomy Robotic surgery National Cancer Database

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

Reconstruction of the Indigenous Sources of Gold of the Glu-Kharinsky Placer (Kolyma River Basin, Magadan Region, Russia)

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Natural Resources 2022年第12期13卷 225-241页

作者： Natalya Evgenievna Savva aleksandr aleksandrovich Biruykov Anton Nikolaevich Gluhov Shilo North-East Interdisciplinary Scientific Research Institute Far Eastern Branch of the Russian Academy of Sciences Magadan Russia

A comparative analysis of typomorphic features of gold placers and indigenous sources of gold was carried out for the Glukharinsky ore-placer node (the Nadezhda deposit and Glukharinskoye, Tyomnoye, and Tyi-Jurye ore occurrences). A correlation between fineness of placer native gold and composition of relic minerals preserved inside gold particles was obtained for the first time. This made it possible to establish mineral parageneses of native gold from potential indigenous sources. The study of placer gold fineness in combination with com-position of mineral inclusions allowed us to identify seven types of gold paragenesis: petzite-hessite with a fineness of 855‰, pyrite-polybasite-galena (a fineness of 670‰), bismuth telluride (900‰), cosalite-vikingite (790‰), galena (870‰), glaucodot (950‰), and hydrohematite (840‰). It was also shown that the placer contains the material from ore occurrences of different formation: gold-quartz-porphyry occurrences in granitoids (Au-Te-Bi type) and gold-silver occurrences. The method developed by us allows one to estimate the percentage of each ore source in placer formation.

关键词： Ore-Placer Node Native Gold Mineral Associations Placer Indigenous Sources

长英质熔体中钛铁矿扮演的角色作用：来自活塞圆筒实验的探索

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长英质熔体中钛铁矿扮演的角色作用：来自活塞圆筒实验的探索

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

第十届全国成矿理论与找矿方法学术讨论会

作者：李家掀 Stepanov aleksandr 蒋少涌中国地质大学资源学院中国地质大学资源学院Key State Laboratory

钛铁矿一般出现在超基基性岩体中,云英岩化的伟晶岩矿床中也较为常见,而在花岗岩体系中常以副矿物的形式出现。Ishihara(1977)依据钛铁矿的存在将花岗岩分为两类:磁铁矿型花岗岩与钛铁矿型花岗岩,钛铁矿类型的花岗岩一般具有更低的氧逸...

钛铁矿一般出现在超基基性岩体中,云英岩化的伟晶岩矿床中也较为常见,而在花岗岩体系中常以副矿物的形式出现。Ishihara(1977)依据钛铁矿的存在将花岗岩分为两类:磁铁矿型花岗岩与钛铁矿型花岗岩,钛铁矿类型的花岗岩一般具有更低的氧逸度。此外,钛铁矿型花岗岩伴随着钨锡矿矿床的出现,

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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

On the role of surface carbonate species in determining the cycling performance of all-solid-state batteries

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Materials Futures 2022年第2期1卷 116-120页

作者： Florian Strauss Seyedhosein Payandeh aleksandr Kondrakov Torsten Brezesinski Battery and Electrochemistry Laboratory(BELLA) Institute of NanotechnologyKarlsruhe Institute of Technology(KIT)Hermann-von-Helmholtz-Platz 176344 Eggenstein-LeopoldshafenGermany BASF SE Carl-Bosch-Str.3867056 LudwigshafenGermany

This short perspective summarizes recent findings on the role of residual lithium present on the surface of layered Ni-rich oxide cathode materials in liquid-and solid-electrolyte based batteries,with emphasis placed on the carbonate *** and future research opportunities in the development of carbonate-containing protective nanocoatings for inorganic solid-state battery applications are also discussed.

关键词： electrochemical energy storage layered oxide cathode materials protective coatings surface contaminants interfacial chemistry

Frequency-Domain Wideband Acoustic Noise Cancellation System

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Journal of Applied Mathematics and Physics 2023年第8期11卷 2523-2532页

作者： Vera Andreevna Karaseva Aleksey Vital’evich Lvov aleksandr Alekseevich Rodionov Federal Research Center A.V. Gaponov-Grekhov Institute of Applied Physics of The Russian Academy of Sciences (IAP RAS) Nizhny Novgorod Russia

When building an adaptive noise cancellation system for wideband acoustic signals, one can meet some difficulties in practical implementation of such a system. The major problem is related to the necessity of using real-time signal generation and processing. In this paper the active noise control system which utilizes adaptation in frequency domain is considered. It is shown that the proposed algorithms simplify practical implementation of a noise cancellation system. The results of computer simulations and prototype experiments show the effectiveness of the proposed methods. .

关键词： Active Noise Cancellation System Adaptive Noise Cancellation

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冻土水分迁移机理研究:评述与展望

冰川冻土 2023年第2期45卷 588-598页

作者：温智邓友生冯文杰 aleksandr ZHIRKOV 张莲海高樯中国科学院西北生态环境资源研究院冻土工程国家重点实验室甘肃兰州730000 Melnikov Permafrost Institute Siberian BranchRussian Academy of SciencesYakutsk 117997Russia

土冻结过程中的水分迁移、积聚是冻害形成的关键环节,至今仍是冻土物理学研究的前沿和重要课题。二十世纪七八十年代冻土水分迁移研究黄金时代以后,长期未有经典理论和科学认知的重大突破,冻土水分迁移中涉及的许多机理性问题和关键瓶... 详细信息

土冻结过程中的水分迁移、积聚是冻害形成的关键环节,至今仍是冻土物理学研究的前沿和重要课题。二十世纪七八十年代冻土水分迁移研究黄金时代以后,长期未有经典理论和科学认知的重大突破,冻土水分迁移中涉及的许多机理性问题和关键瓶颈难题至今仍不能准确回答,尚存在很多争议和认识上的不足,现有研究成果在实际工程中的应用并不令人完全满意。因其性质的易变性、微观性和突变性,冻结相变区(冻结缘)仍是冻土水热输运研究中的一个“黑箱”。研究评述了冻土水分迁移驱动力与迁移过程相关研究的发展历程、主要研究进展与现状;分析了孔隙水压力、土水势驱动冻土水分迁移的物理原理和基本规律,综述了孔隙水压力、土水势的理论表征与试验测试等方面的最新进展、认知现状与主要科学问题;分析了三种流行的冻土水分迁移理论,即毛细水迁移理论、薄膜水迁移理论和水汽迁移理论;总结了制约冻土水分迁移科学认知突破的关键瓶颈难题,展望了未来研究的重点和方向。认为未来的研究应加强仪器设备的改进、研发与新技术引入,重点关注冻土水分迁移驱动力的物理本质和精准监测,强化冻土水分迁移的微观过程及机制认识,需从非平衡态热力学的视角关注热质输运与冰-水相变过程,注重工程化冻土多物理场模型的开发与自主开源计算平台的构建。本文旨在系统梳理冻土水分迁移机理的研究历史与现状,总结概述冻土水分迁移研究在新思想、新理论、新方法和新技术等方面的最新研究动态,凝练指出亟待解决的前沿科学问题和未来研究的重点,促进冻土热质输运基础理论的发展与完善,更好地服务于寒区工程冻融灾害和环境问题的解决。

关键词：冻土水分迁移毛细水薄膜水克拉伯龙方程

提高KF-AlF_(3)-Al_(2)O_(3)熔体中Cu-Al基阳极的耐腐蚀性

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Transactions of Nonferrous Metals Society of China 2022年第1期32卷 354-363页

作者： Sai Krishna PADAMATA Andrey YASINSKIY aleksandr SHABANOV Timofey BERMESHEV 杨酉坚王兆文曹导 Peter POLYAKOV Laboratory of Physics and Chemistry of Metallurgical Processes and Materials Siberian Federal UniversityKrasnoyarskRussia Laboratory of Molecular Spectroscopy Krasnoyarsk Science Center SB RASKrasnoyarskRussia 东北大学冶金学院沈阳110819

采用恒电流和动电位极化技术研究经预氧化的和未经预氧化的Cu-Al基阳极(Cu-10Al和Cu-9.8Al-2Mn)在KF-AlF_(3)-Al_(2)O_(3)熔体中的阳极行为。将合金在700℃下进行短时间(8 h)氧化,然后在800℃下施以0.4 A/cm^(2)的电流密度进行1 h恒电... 详细信息

采用恒电流和动电位极化技术研究经预氧化的和未经预氧化的Cu-Al基阳极(Cu-10Al和Cu-9.8Al-2Mn)在KF-AlF_(3)-Al_(2)O_(3)熔体中的阳极行为。将合金在700℃下进行短时间(8 h)氧化,然后在800℃下施以0.4 A/cm^(2)的电流密度进行1 h恒电流极化。测定扫描速率为0.01 V/s的动电位曲线。对在阳极表面冻结的熔体样品进行XRD分析,并在实验后对阳极进行SEM分析,以研究合金表面形成的氧化皮的物相。所有阳极材料的稳态电位都在2.30~2.50 V(vs Al/AlF_(3))范围内。根据动电位极化获得的数据计算阳极的腐蚀速率。结果表明,经预氧化的阳极比未经预氧化的阳极具有更低的腐蚀速率。

关键词：惰性阳极钾冰晶石 Cu-Al合金腐蚀铝电解析氧电极