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Experimental Sex Inversion of.Chicken Embryos at Aromatase Inhibition, Estrogen Receptor Modulation, DNA Demethylation and Progesterone Treatment

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Natural Science 2016年第11期8卷 451-459页

作者： Antonina V. Trukhina Natalia A. Lukina aleksandr f. smirnov Department of.Genetics and Biotechnology St. Petersburg State University St. Petersburg Russia

The work was carried out by microinjections of.an aromatase inhibitor letrozole, an estrogen receptor modulator tamoxif.n in incubated eggs Gallus g. domesticus, the f.rst day of.incubation. It also used 5-azacytidine (5-AC) at the same time. Injection of.progesterone was carried out bef.re the onset of.meiosis prophase 1 on 16 h of.incubation. Morphologically and histologically and by PCR, sex of.the 17-day embryos was controlled. According to inf.rmation received microinjection of.letrozole caused almost a 100% inversion of.genetic males to f.males, which is manif.sted in the morphology of.the gonads. In other experiments, sex reversal is not revealed. The results are obtained in this study, and the data suggest that the presence of.gonadogenesis in f.male chickens makes earlier emergence of.aromatase in the beginning of.incubation, than that according to the classical scheme of.sex determination in birds. Presumably this kind of.synthesis is triggered by some W-chromosomal f.ctors. It f.iled to detect the phenomenon of.gender inversion—the transf.rmation of.males into f.males af.er exposure to demethylating agent 5-AC that casts doubt on the participation of.male hypermethylated (MHM)-RNA-segment in regulating the activity of.sex determining genes.

关键词： Gallus gallus Sex Determination Aromatase Gonad DMRT1

Hetero-integrated high-peak-optical-power laser source (940 nm) f.r time-of.f.ight sensors

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Chinese Optics Letters 2024年第7期22卷 81-85页

作者： Sergey Olegovich Slipchenko aleksandr aleksandrovich Podoskin Ilia Vasil'evich Shushkanov Marina Gennad'evna Rastegaeva Artem Eduardovich Rizaev Matvey Igorevich Kondratov Artem Evgen'evich Grishin Nikita aleksandrovich Pikhtin Timur Anatol'evich Bagaev Maxim Anatol'evich Ladugin aleksandr Anatol'evich Marmalyuk Vladimir aleksandrovich Simakov Iof.e Institut Russian Academy of SciencesSt.Petersburg 194021Russia Open Joint-Stock Company M.f.Stel’makh Polyus Research Institute Moscow 117342Russia RUDN University Moscow 117198Russia

The generation of.high-power laser pulses using a compact hetero-integrated assembly based on a semiconductor laser with a dual-element composite 2μm×100μm aperture and a compact heterothyristor switch is *** achieved peak optical power was 33 W with a pulse duration of.3 ns at a thyristor operating voltage of.55 *** leading edge of.the laser pulse turn-on was 50 ps to a power level of.24.7 W,and the turn-on delay between the elements of.the composite aperture was 160 ps.

关键词： hetero-integrated assembly semiconductor lasers thyristor switches LIDAR gain-switching mode laser heterostructure

Elucidating elusive quaternary selenide EuCeCuSe3:Synthesis,crystal structure,properties and theoretical studies

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Journal of.Rare Earths 2024年第1期42卷 163-171,I0006页

作者： Maxim V.Grigoriev Anna V.Ruseikina Maxim S.Molokeev Vladimir A.Chernyshev aleksandr S.aleksandrovsky Alexander S.Krylov Svetlana N.Krylova Nikolai P.Shestakov Dmitriy A.Velikanov Alexander A.Garmonov Alexey V.Matigorov Evgeny A.Ostapchuk Thomas Schleid Damir A.Saf.n Laboratory of.Theory and Optimization of.Chemical and Technological Processes University of TyumenVolodarskogo Str.6625003TyumenRussian Federation Kirensky Institute of.Physics Federal Research Center KSC SB RASAkademgorodok 50 Bld.38660036KrasnoyarskRussian Federation Department of.Physics Far Eastern State Transport UniversitySerysheva Str.47680021KrasnoyarskRussian Federation Institute of.Natural Sciences and Mathematics Ural Federal University Named After the First President of Russia B.N.YeltsinMira Str.19620002EkaterinburgRussian Federation Department of.Photonics and Laser Technology Siberian Federal UniversitySvobodnii Ave.79660079KrasnoyarskRussian Federation Institute of.Physics and Technology University of TyumenVolodarskogo Str.6625003 TyumenRussian Federation Institute f.r Inorganic Chemistry University of StuttgartPfaffenwaldring 55D-70569StuttgartGermany Scientif.c and Educational and Innovation Center f.r Chemical and Pharmaceutical Technologies Ural Federal University named after the First President of Russia B.N.YeltsinMira Str.19620002 EkaterinburgRussian Federation University of.Tyumen Volodarskogo Str.6625003TyumenRussian Federation

We report on the novel heterometallic quaternary selenide EuCeCuSe3,the f.brication of.which has been a challenge until this *** structure of.the reported selenide was elucidated f.om the powder X-ray dif.raction data,which revealed the f.rmation of.EuCeCuSe3with excellent yield(96.7%)accompanied with a minor f.action of.CeSe2(3.3%),and was best solved in orthorhombic space group Pnma with the BaLaCuS3structural ***,the crystal structure of.the title compound completes the row of.the heterometallic quaternary selenides EuRECuSe3(RE=La,Pr,Nd,Sm,Eu,Gd,Tb,Dy,Ho,Er,Tm,Yb,Lu,Y),of.which the cerium-based derivative exclusively belongs to the BaLaCuS3structural *** distortion of.the CuSe4polyhedron was compared f.r the whole series of.EuRECuSe3compounds using theτ4-descriptor f.r f.ur coordinated ions,which revealed the highest degree of.distortion f.r the Ce3+-containing selenide,f.llowed by the La3+-based ***,the crystallographic and geometrical parameters of.the reported selenide were discussed in comparison to the Ce3+-based sulf.des SrCeCuS3and *** initio calculations of.the crystal structure,a phonon spectrum and elastic constants f.r the crystal of.EuCeCuSe3were also *** types and wavenumbers of.f.ndame ntal modes were determined and the involvement of.ions participating in the phonon modes was *** experimental IR spectrum of.the reported selenide was interpreted and f.und to be in agreement with the calculated *** experimental direct band gap of.EuCeCuSe3was measured to be 1.36 eV that is consistent with the concept of.its origin due to interband transitions between orbitals emerging mainly f.om 4f.valence band)and 5d(conduction band)levels of.the Eu2+*** dependence of.the Young’s modulus on the direction demonstrates the anisotropy of.the elastic properties,while the Vickers hardness f.r EuCeCuSe3was calculated to be 5.2 ***,the title compound is paramagnetic above 4 K.

关键词： Quaternary selenide Synthesis Crystal structure Ab initio calculations Magnetic measurements Spectroscopy

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 platf.rm has become an attractive tool f.r 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 f.r three dif.erent 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-f.r *** survival was def.ned 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 af.er controlling f.r 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(Pf.r cancer and did not dif.er by the procedure type(P=0.26).Vascular invasion was noted in 42.6%of.LNs and did dif.er by the approach:42.1%f.r open,44.0%f.r laparoscopic and 47.2%f.r robotic PD(P=0.015).Median survival f.r 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

Multilayered organic semiconductors f.r high perf.rmance optoelectronic stimulation of.cells

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Nano Research 2023年第4期16卷 5809-5816页

作者： aleksandr Markov Alexander Gerasimenko Annie-Kermen Boromangnaeva Sof.a Shashova Elena Iusupovskaia Ulyana Kurilova Vita Nikitina Irina Suetina Marina Mezentseva Mikhail Savelyev Peter Timashev Dmitry Telyshev Xing-Jie Liang Institute f.r Bionic Technologies and Engineering I.M.Sechenov First Moscow State Medical UniversityMoscow 119991Russia Institute of.Biomedical Systems National Research University of Electronic TechnologyZelenogradMoscow 124498Russia Chemistry Department Lomonosov Moscow State UniversityLeninskie Gory1/3Moscow 119991Russia Ivanovsky Institute of.Virology N.F.Gamaleya National Center of Epidemiology and MicrobiologyMoscow 123098Russia World-Class Research Center“Digital Biodesign and Personalized Healthcare” I.M.Sechenov First Moscow State Medical UniversityMoscow 119991Russia Laboratory of.Clinical Smart Nanotechnologies I.M.Sechenov First Moscow State Medical UniversityMoscow 119991Russia Institute f.r Regenerative Medicine I.M.Sechenov First Moscow State Medical UniversityMoscow 119991Russia CAS Key Laboratory f.r Biomedical Ef.ects of.Nanomaterials and Nanosaf.ty CAS Center for Excellence in NanoscienceNational Center for Nanoscience and Technology of ChinaBeijing 100190China University of.Chinese Academy of.Sciences Beijing 100049China

The ef.iciency of.devices f.r bioelectronic applications,including cell and tissue stimulation,is heavily dependent on the scale and the perf.rmance *** miniaturization of.stimulation electrodes,achieving a suf.iciently high current pulse to elicit action potentials becomes an *** we report on our approach of.vertically stacking organic p-n junctions to create highlyef.icient multilayered organic semiconductor(MOS)photostimulation device.A tandem arrangement substantially increases the photovoltage and charge density without sacrif.cing lateral area,while not exceeding 200-500 nm of.*** devices generate 4 times higher voltages and at least double the charge densities over single p-n junction devices,which allow using lower light intensities f.r *** devices show an outstanding stability in the electrolyte that is extremely important f.r f.rthcoming in vivo ***,we have validated MOS devices perf.rmance by photostimulating f.broblasts and neuroblasts,and f.und that using tandem devices leads to more ef.ective action potential *** a result,we obtained up to 4 times enhanced ef.ect in cell growth density using 3 p-n layered *** results corroborate the conclusion that MOS technology not only can achieve parity with state-of.the-art silicon devices,but also can exceed them in miniaturization and perf.rmance f.r biomedical applications.

关键词： bioelectronics organic semiconductors wireless stimulation f.broblasts neuroblastoma cells

On the role of.surf.ce carbonate species in determining the cycling perf.rmance of.all-solid-state batteries

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Materials f.tures 2022年第2期1卷 116-120页

作者： f.orian 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 f.ndings on the role of.residual lithium present on the surf.ce of.layered Ni-rich oxide cathode materials in liquid-and solid-electrolyte based batteries,with emphasis placed on the carbonate *** and f.ture research opportunities in the development of.carbonate-containing protective nanocoatings f.r inorganic solid-state battery applications are also discussed.

关键词： electrochemical energy storage layered oxide cathode materials protective coatings surf.ce contaminants interf.cial chemistry

尔丹盾爱尔康地台第四纪沉积物的热物理性质(英文)

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黑龙江大学工程学报 2014年第3期5卷 215-219页

作者： Rev I.Gavriliev Anatolii R.Kirillin aleksandr f.Zhirkov 俄罗斯科学院西伯利亚分院麦尔尼科夫冻土研究所

对于爱尔康地垒第四纪沉积物的地热性的有效值和物理参数而言，其事实上不仅是构成沉积物的活性层，而更有助于评价爱尔康煤矿冻土区的基础设施和工程。爱尔康地垒沉积物的厚度从几米到十几米，这以下的事实相符，在第四纪大地构造发展... 详细信息

对于爱尔康地垒第四纪沉积物的地热性的有效值和物理参数而言，其事实上不仅是构成沉积物的活性层，而更有助于评价爱尔康煤矿冻土区的基础设施和工程。爱尔康地垒沉积物的厚度从几米到十几米，这以下的事实相符，在第四纪大地构造发展阶段，爱尔康地垒遭受了弧形块的不同的振幅和强度的不断膨胀。根据从初始到第四纪沉积残留物选出渣油，洪积层，崩积和冲积层。他们是由花岗岩片麻岩组成的。在岩石材料较多的斜坡上的渣油和冲积层，其由砂和粉砂组成结合砾石和粗砾石。在超过10种类型的土壤元素工程地质剖面上，其热导率为0.50～2 W/（M· K），其热导率如下：堆积层为1.51 W/（M· K）、洪积层为1.32 W/（M· K）、冲积层为1.50 W /（M· K）。对于给出的爱尔康矿区工程地质段的主要元素物理和热物理参数的平均值和极限值而言，由所呈现的元素的组合构成。在德林达河段呈现爱尔康岩性剖面特征，在科纳-苏拉河头，沿着Uzky支流和1号营矿所设计的道路也呈现出这一特征。所有类型的矿床成因和位置的地形形式：分水岭，斜坡和山谷都包括在内。获得爱尔康地垒第四纪沉积的整个厚度的热物理性质和物理参数的有效值，是以表的形式汇总，该有效值有助于预测基础设施和周边炼油设施，并为热分析的爱尔康铀矿床的开发提供了依据。

关键词：地垒第四纪沉积物活性层工程地质记录导热系数比热容

Do non-dipole geomagnetic f.eld behaviors persistently exist in the subarctic Pacif.c Ocean over the past 140 ka?

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Science Bulletin 2020年第18期65卷 1505-1507,M0003页

作者： Yi Zhong Yanguang Liu Xiaoqiang Yang Jian Zhang Jiabo Liu aleksandr Bosin Sergey A.Gorbarenko Xuef. Shi Ting Chen Yu-Min Chou Wei Liu Haosen Wang Congcong Gai Jianxing Liu Alexander NDerkachev Xiaoke Qiang Qingsong Liu Centre f.r Marine Magnetism Department of Ocean Science and EngineeringSouthern University of Science and TechnologyShenzhen 518055China Key Laboratory of.Marine Sedimentology and Metallogeny First Institute of OceanographyMinistry of Natural ResoursesQingdao 266061China Laboratory f.r Marine Geology Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266061China Department of.Earth Science Sun Yat-sen UniversityGuangzhou 510275China Key Laboratory of.Computational Geodynamics University of Chinese Academy of SciencesBeijing 100049China V.I.Il'ichev Pacif.c Oceanological Institute Far East Branch of Russian Academy of ScienceVladivostok 690041Russia State Key Laboratory of.Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Research School of.Earth Sciences Australian National UniversityCanberra ACT 2601Australia State Key Laboratory of.Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi'an 710061China

Paleomagnetic records f.om globally distributed locations are essential f.r f.lly understanding geomagnetic f.eld variations,particularly non-dipole f.eld f.uctuations[1].Paleomagnetic studies on historical time scales have demonstrated the existence of.persistent geomagnetic f.ux patches,such as the Canadian(North America)and Siberian(East Asia)f.ux lobes,which may result f.om an organizing structure imposed on the geomagnetic f.eld by lower mantle heterogeneity[2].Holocene paleomagnetic secular variations,reconstructed f.om the Alaskan margin of.the Subarctic Pacif.c Ocean(SPO)[3]and revealed by dynamo modeling[4],f.rther suggest that time-varying f.ux expulsions on the core-mantle boundary recurrently occur in high-latitude locations(***).

关键词： geomagnetic mantle Holocene

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小型无人飞行器控制系统设计

小型无人飞行器控制系统设计

作者：亚历山大·乌恰耶夫（UCHAEV aleksandr）哈尔滨工业大学

学位级别：硕士

随着现代技术在空气动力学,复合材料,惯性导航系统的发展,以及先进的电子技术,机器人技术和计算机技术领域取得的成就,无人驾驶飞机系统有望提高到的一个新的水平。虽然无人机已经扩展到民用和商业,并且在各个领域都以崭露头角,但是不... 详细信息

随着现代技术在空气动力学,复合材料,惯性导航系统的发展,以及先进的电子技术,机器人技术和计算机技术领域取得的成就,无人驾驶飞机系统有望提高到的一个新的水平。虽然无人机已经扩展到民用和商业,并且在各个领域都以崭露头角,但是不管在技术上还是在实用性上都存在一些不足。小型无人机已经在如下领域取得可喜可贺的成就:环境实时监测,空中侦察,专用通信网络,道路交通实时控制,国土远程监控,搜寻搜救等。微型无人机(MAV)的种类取决于固定机翼的尺寸,通常分为两种:第一种无人机(UAV)的机翼长1.5?3米,汽油发动机,需要专用的跑道;另一种无人机机翼长不超过1.5米,通常使用电动马达,不需要跑道。尽管无人机在机翼的尺寸上存在着差异,但是控制方法是通用的,控制对象也是类似的-MAV。在本文中,我们讨论的范畴仅限于固定翼无人驾驶飞机。研究工作主要分为五个部分:(1)这部分主要叙述了无人机操作系统存在的历史问题,分析了研究的目的和相应对的研究意义,提出的论文的整体结构,并讨论了仿真的设计方法。在章节的结尾,分析了系统的组成,系统的控制(自动驾驶的初步评价),并简要讨论了风向对飞机飞行的影响。(2)在第2章中,首先确定飞行器的坐标系和变换矩阵,以及为了接下来求解方程的基准点,在这样的模型中,选定欧拉角。然后,定义基本状态变量,基于牛顿定律的基础上推导运动学(位置和速度之间的关系)和动力学方程(力和力矩之间的关系,以及位移量),在Simulink创建模型。接下来考虑作用在飞行器上动力学方程,以及边界层分离(f.ow separation ef.ect)效应,模型的结果是12个非线性耦合的一阶微分方程组。这样相应的模型已在Matlab和Simulink建立并分析。由于在飞机的飞行中,气流的扰动起着重要的作用。因此通过矢量三角形理论以及冯·卡门理论建立的湍流模型和基于德赖登理论的随机扰动的传递函数,并且从MIL-f.8785确定湍流模型参数。相应的模型在Matlab和Simulink研究。考虑到六个自由度的飞行器的模型是一组12个方程组成的方程非线性耦合系统,控制器的参数设计起来极为困难。因此,上述飞行器建立的模型(在纵向动力学和横向动力学)需要在平衡位置线性化。这样得到的平衡位置线性化的飞行器(trim f.ight)模型正是我们需要并研究的。接着,在平衡位置线性化的动力学模型基础上考虑侧滑运动的传递函数(滚动角,轨道角,侧滑角),和纵向运动(俯仰角,高度,空速)。通过奈奎斯特轨迹分析在开环和闭环系统下传递函数的鲁棒性。所有的传递函数的分析表明系统是稳定的或中性的因此,建立的飞行器模型(按照它的微分稳定性)是一种稳定的结构。本章最后在matlab和simulink环境设计的飞行模拟器,对航模的位置,以及飞机的基本参数的值进行实时跟踪。随后,飞行模拟器既可以扩展到研究系统(自动驾驶和系统的初步评估),也可以对系统进行高层次的分析。(3)由于无人机自动驾驶是所有飞行阶段完整的控制系统,其中,典型地自动驾驶系统被分成两个部分,底层系统-用于控制飞行器如高度,空速,航向角;上层的控制系统-来确定飞行路线和遵循的飞行路线。在第三章中,基于闭环反馈的控制系统底层控制系统设计。控制系统设计的想法是现在内环计算简单的闭环系统,然后计算外环即整体的(可能计算所有的比较复杂)控制系统。自动驾驶仪的设计适用于无人机上mav使用的传感器和计算设备。每个控制回路(除横滚和俯仰控制回路以外)设计为pi控制器。对于横滚和俯仰控制回路分别采用pid控制器和pd控制器。对于俯仰角选择pd控制器,是因为积分会对控制回路相应速度产生负面影响的。至于自动驾驶仪的计算被用来解耦动力系统传递函数(decoupledtf.。控制系统被设计为横向和纵向运动。除了考虑控制系统结构的问题,还要考虑系统饱和问题以及对控制性能的影响。为了解决控制器饱和的问题,从信号积分器减去能使信号保持在饱和控制中的变量。此外,引入偏离控制面的最大偏移量。设定每个控制环所需动态响应,并在确定控制器增益的基础上获得典型传递函数。但由于这些公式包括选择用于设计所需要的增益参数,它提出了一种基于根的质量方法。这种方法不仅可以选择所需的动态收益,又保证了控制系统的稳定性。因为有些环路会对外部环路造成影响,所以在选择系统增益,需要考虑不同频率参数之间的干扰。同样地,对于调节飞行器速度和飞行高度,为了实现无人机的纵向运动(通过调节发动机和俯仰角),使用有限状态自动机获得最优的调节高度。无人机控制的研究最初需要测试每个回路的性质和性能。章节的结尾对不同的飞行任务进行了测试(没有气体扰动的影响)。为了测试自动驾驶在大气扰动的影响下,在一个控制机动的形式提供测试信号。这个信号是测试飞机的所有状态,并给出自动驾驶仪给的完整的评估。控制机动研究工作

关键词：小型无人飞行器 EKf LPf 底层飞行控制系统连续闭环方法