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Two New Species of Eretmophyllum(Ginkgoales)from the Jurassic of Eastern Siberia

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Acta Geologica Sinica(English Edition) 2023年第4期97卷 1014-1025页

作者： andrey frolov Irina MASHCHUK Institute of the Earth's Crust Siberian Branch of the Russian Academy of SciencesIrkutsk 664033Russia

Two new species of Eretmophyllum Thomas are described from the lower(Toarcian)and upper(Aalenian)Prisayan Formation of the Irkutsk Basin,Eastern Siberia,Russia based on distinct morphological and cuticular features of the leaves that distinguish them from other species of the *** polypapillosum *** characterized by the presence of 2-3 papillae on the lower and upper epidermis of ordinary ***,the leaf burials of *** *** that it preferred mesophilic forests developed on river terraces and/or low *** yershowskiensis *** represented exclusively by leaf cuticles extracted by coal maceration,and it probably inhabited the low banks of peat *** presence of the genus Eretmophyllum in the Early Jurassic of France and Eastern Siberia shows that it was already widespread in the territory of Eurasia,distributed from Western Europe to Eastern *** indicates the possible existence of Eretmophyllum species elsewhere in the Early Jurassic such as Central Asia and Northwest China.

关键词： paleobotany ginkgoalean taxonomy paleophytogeography paleoecology leaf cuticles Irkutsk Coal Basin

Monocotyledon-like Leaves from the Middle Jurassic of East Siberia(Russia)

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Acta Geologica Sinica(English Edition) 2022年第6期96卷 1884-1896页

作者： andrey frolov Ilya ENUSHCHENKO Institute of the Earth’s Crust Siberian Branch of the Russian Academy of SciencesIrkutsk 664033Russia Limnological Institute Siberian Branch of the Russian Academy of SciencesIrkutsk 664033Russia

Leaf fragments of Herbifolia antiqua *** et Enushchenko *** *** the Middle Jurassic(Aalenian)of the Irkutsk Coal Basin(Eastern Siberia,Russia)are *** following features are characteristic of *** *** ***.:the presence of leaf sheaths,linear smooth-edged leaves with parallel venation,anastomoses between the veins,anomocytic stomata,rhomb-shaped ordinary epidermal *** a combination of characters is widespread in modern monocotyledonous plants and is absent in fossil and modern cryptogam and *** to the lack of evidence of an enclosed ovule in *** *** ***.,we attribute it to a typological angiosperm,based on its unique leaf structure characteristic of *** leaf epidermal structure of Herbifolia *** most similar to those of modern Asparagales and Liliales.

关键词： monocotyledons leaf epidermis new taxa Jurassic angiosperm Irkutsk Coal Basin

Mixed Cerebrovascular and Alzheimer’s Type Pathology Mimicking Lewy Body Disease and Its Possible Contribution to Cognitive Impairment in Elderly Patients with Bipolar Disorder/Schizophrenia

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Open Journal of Pathology 2022年第3期12卷 88-99页

作者： andrey frolov Lokesh Coomar Miguel A. Guzman John R. Martin III Center for Anatomical Science and Education Department of Surgery Saint Louis University School of Medicine Saint Louis MO USA Departments of Pathology and Neurology Saint Louis University School of Medicine Saint Louis MO USA

The fast aging human population requires new approaches to reliable diagnosis and proper treatment of dementia in elderly patients with psychiatric disorders such as bipolar disorder (BD) and schizophrenia (SCZ). As compared to other psychiatric disorders, BD and SCZ are characterized by increased and similar risk for dementia as well as cerebrovascular (CVD) and Parkinson’s (PD) diseases independent of the patient’s age. There are reports in the literature suggesting BD and SCZ in older patients could cause dementia without contribution from the neurodegenerative diseases, including Alzheimer’s disease (AD), due to the absence of the known neuropathology associated with cognitive decline in such individuals. This view contradicts a plethora of data highlighting AD as a major cause of dementia in the elderly. This issue was addressed by examining postmortem cerebral pathology in an 83-year-old female diagnosed with BD, SCZ, and PD (D1) and comparing it to that of a second donor (D2), an age-matched male diagnosed with Lewy Body Dementia (LBD). Upon thorough histochemical and immunohistochemical examinations of both brains, the PD and LBD diagnoses in D1 and D2 were not confirmed. Instead, AD-related pathology was observed in both subjects with AD advancing to its clinical stage (mild to moderate) only in D1. Diffuse β-amyloid peptide 1-42 (Aβ1-42) staining, most likely reflecting a presence of the Aβ1-42 soluble form, was also detected in cerebellar neurons and cerebellar extracellular space in D1 and D2. Cerebrovascular pathology was pronounced and distinct in both brains and included amyloid angiopathy, hyaline atherosclerosis, microbleeds, and dilated Virchow Robin spaces in D1 as well as thick-walled blood vessels with microbleeds in D2. It was concluded that a mixed AD and cerebrovascular pathology could mimic Lewy Body Disease and potentially contribute to dementia development in elderly BD and SCZ patients.

关键词： Bipolar Disorder Schizophrenia Alzheimer’s Disease Cerebrovascular Disease Neuropathology

A Rare Case of 83-Year-Old Transgender Female: Can Thyroid Hormone Deficiency Be Involved in Transgenderism and Gender Dysphoria?

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Advances in Sexual Medicine 2020年第2期10卷 23-40页

作者： andrey frolov Lauren Polcaro Craig Lawson Yun Tan John R. Martin III Center for Anatomical Science and Education Department of Surgery School of Medicine Saint Louis University Saint Louis Missouri USA

In the current report, we describe an 83-year-old biological male who self- identified as a female by legally changing his first and middle names to female ones and whose death certificate states his sex as a female. The medical history of this individual indicated complete penectomy without further specification. Postmortem physical examination revealed an absence of penis with a large scrotum, transposed urethral orifice, and small testes. The histological analysis of the testes identified abnormal epithelium in the seminiferous tubules that lacked germ and Sertoli cells as well as the interstitium without Leydig cells present. The exome sequencing of the individual’s DNA using the Next Generation Sequencing (NGS) Illumina platform revealed no genetic variants associated with either penile or urethral cancer that could have explained the complete penectomy, but pointed toward a potentially impaired production of T3 and T4 thyroid hormones which could account for the observed testicular malformation. Overall, the data obtained raise an important question as to whether the thyroid hormone axis could be an important part of the hormonal architecture supporting male sexual behavior.

关键词： Transgenderism Gender Dysphoria Next Generation Sequencing Thyroid Peroxidase Cilia

Modeling antiphase boundary energies of Ni_(3)Al-based alloys using automated density functional theory and machine learning

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npj Computational Materials 2022年第1期8卷 757-766页

作者： Enze Chen Artur Tamm Tao Wang Mario E.Epler Mark Asta Timofey frolov Department of Materials Science and Engineering University of CaliforniaBerkeleyCA94720USA Materials Sciences Division Lawrence Berkeley National LaboratoryBerkeleyCA94720USA Materials Science Division Lawrence Livermore National LaboratoryLivermoreCA94550USA Carpenter Technology Corporation PhiladelphiaPA19103USA

Antiphase boundaries(APBs)are planar defects that play a critical role in strengthening Ni-based superalloys,and their sensitivity to alloy composition offers a flexible tuning parameter for alloy ***,we report a computational workflow to enable the development of sufficient data to train machine-learning(ML)models to automate the study of the effect of composition on the(111)APB energy in Ni_(3)Al-based *** employ ML to leverage this wealth of data and identify several physical properties that are used to build predictive models for the APB energy that achieve a cross-validation error of 0.033 J m^(−2).We demonstrate the transferability of these models by predicting APB energies in commercial ***,our use of physically motivated features such as the ordering energy and stoichiometry-based features opens the way to using existing materials properties databases to guide superalloy design strategies to maximize the APB energy.

关键词： Ni_(3)Al alloy superalloy

Stimulated electromagnetic emissions spectrum observed during an X-mode heating experiment at the European Incoherent Scatter Scientific Association

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Earth and Planetary Physics 2019年第5期3卷 391-399页

作者： Xiang Wang Chen Zhou Tong Xu Farideh Honary Michael Rietveld Vladimir frolov Department of Space Physics School of Electronic InformationWuhan UniversityWuhan 430072China National Key Laboratory of Electromagnetic Environment China Research Institute of Radiowave PropagationQingdao 266107China Department of Physics Lancaster UniversityLancaster LA1 4YBUK EISCAT Scientific Association N-9027 RamfjordmoenNorway Institute for Physics and Technology UiT The Arctic University of NorwayN-9037TromsφNorway Radiophysical Research Institute Nizhny Novgorod 603600Russia Kazan Federal University Kazan 420008Russia

An extraordinary(X-mode)electromagnetic wave,injected into the ionosphere by the ground-based heating facility at Tromsφ,Norway,was utilized to modify the ionosphere on November 6,*** high-power high-frequency transmitter facility located at Tromsφ belongs to the European Incoherent Scatter Scientific *** the experiment,stimulated electromagnetic emission(SEE)spectra were observed.A narrow continuum occurred under cold-start conditions and showed an overshoot effect lasting several *** peaks occurred on both sides of the heating frequency only in the preconditioned ionosphere and also showed an overshoot *** SEE features are probably related to the ponderomotive process in the X-mode heating experiment and are helpful for understanding the physical mechanism that generated them during the X-mode heating *** features observed in the X-mode heating experiments are novel and require further investigation.

关键词： artificial ionosphere modification stimulated electromagnetic emissions extraordinary electromagnetic wave European Incoherent Scatter Scientific Association(EISCAT)

The first joint experimental results between SURA and CSES

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Earth and Planetary Physics 2018年第6期2卷 527-537页

作者： XueMin Zhang Vladimir frolov ShuFan Zhao Chen Zhou YaLu Wang Alexander Ryabov DuLin Zhai Institute of Earthquake Forecasting China Earthquake Administration Beijing 100036 China Radiophysical Research Institute Nizhny Novgorod 603950 Russia Department of Space Physics School of Electronic Information Wuhan University Wuhan 430072 China Kazan Federal University Kazan 420008 Russia

In June 2018, for the first time, the SURA heating facility in Russia, together with the in-orbit China Seismo-Electromagnetic Satellite(CSES), carried out a series of experiments in emitting high frequency(HF) O-mode radio waves to disturb the ionosphere. This paper reports data from those experiments, collected onboard CSES, including electric field, in-situ plasma parameters, and energetic particle flux. Five cases are analyzed, two cases in local daytime and three in local nighttime. We find that the pumping wave frequencies f_0 in local daytime were close to the critical frequency of the F_2 layer f_oF_2, but no pumping waves were detected by the electric field detector(EFD) on CSES even when the emitted power reached 90 MW, and no obvious plasma disturbances were observed from CSES in those two daytime cases. But on June 16, there existed a spread F phenomena when f_0 was lower than f_oF_2 at that local daytime *** the three cases in local nighttime, the pumping waves were clearly distinguished in the HF-band electric field at the emitted frequency with the emitted power only 30 MW; the power spectrum density of the electric field was larger by an order of magnitude than the normal background, with the propagating radius exceeding 200 km. Due to the small f_oF_2 over SURA in June at that local nighttime period, f_0 in these three cases were significantly higher than f_oF_2, all belonging to under-dense heating conditions. As for the plasma parameters, only an increase of about 100 K in ion temperature was observed on June 12; in the other two cases(with one orbit without plasma data on June 17), no obvious plasma disturbances were found. This first joint SURA-CSES experiment illustrates that the present orbit of CSES can cross quite close to the SURA facility, which can insure an effective heating time from SURA so that CSES can observe the perturbations at the topside ionosphere excited by SURA in the near region. The detection of plasma disturbance

关键词： CSES satellite SURA ionospheric perturbations electric field HF pumping wave

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涡轮叶片近气膜孔区域颗粒沉积预测

涡轮叶片近气膜孔区域颗粒沉积预测

作者： frolov Iurii 哈尔滨工业大学

学位级别：硕士

燃气轮机被广泛应用于航空、航天、舰船以及发电等动力装置,直接关系到国家国防和国民经济建设。效率是燃气轮机装置最重要的指标之一,而提高涡轮前温度是提高热效率的重要途径,但提高涡轮前温度会极大提高涡轮叶片抗高温性能的要求。... 详细信息

燃气轮机被广泛应用于航空、航天、舰船以及发电等动力装置,直接关系到国家国防和国民经济建设。效率是燃气轮机装置最重要的指标之一,而提高涡轮前温度是提高热效率的重要途径,但提高涡轮前温度会极大提高涡轮叶片抗高温性能的要求。因此当前提燃气涡轮性能的主要关注点在于一方面需要逐步提高叶片材料本身的性能,另一方面可以通过气膜冷却、内部扰流装置等多种冷却结构组合对叶片进行冷却,能较大提高叶片耐受温度。根据大量文献调研和实际应用案例分析可知,除了高温造成叶片较大热负荷,由于进气杂物以及燃烧产生颗粒物在叶片表面的沉积也是造成涡轮叶片烧蚀的重要因素。颗粒物直接打到壁面会造成局部高温,此外颗粒物沉积还会造成气膜冷却孔堵塞使得局部气膜冷却失效。因此深入研究颗粒物沉积的预测方法以及沉积规律,探讨叶片冷却孔附近颗粒与冷气的相互影响关系,并再现沉积形貌研究其对局部流动换热的影响对于减少叶片烧蚀延长燃气涡轮寿命具有重要意义。本文首先对相关文献进行了综述与分析。鉴于颗粒沉积及预测的复杂性,通过数值方法来进行详细研究还比较困难,目前大多数是实验工作。部分数值工作提出一些简单的数学关系模型对实验结果进行分析或回归,以期望能获得定性的或者一定程度上定量的结果,但是真正通过数值模拟方法进行颗粒沉积预测研究非常少。本文基于FLUENT软件包中粒子的运动和计算模型,通过数值方法对冷却孔附近特定位置和大小颗粒的沉积进行了数值模拟,得到了定性的数值结果,并与实验进行了对比,可信度比较高。本文针对涡轮叶片表面研究了现有的颗粒沉积和反弹模型,这些模型考虑的参数包括材料属性、颗粒速度以及入射角度等参数,但是大部分模型具有一定缺陷,比如没有明确的实验验证,或者没有材料属性和颗粒运动参数,因此模型的获取、整理以及提炼具有相当大的难度。本文讨论了基于实验的一个模型,这个模型只有一个参数为颗粒入射角,这个模型给出了直接关系颗粒在壁面沉积或者反弹的恢复系数。如果恢复系数为1,颗粒在壁面上反弹,该反弹过程满足弹性反弹规律,如果恢复系数为0,则颗粒将粘附沉积在壁面上。本文在此基础上,进一步研究了另一个模型,该模型包含能够影响沉积和反弹预测的大量参数,但没有实验验证。经过系统研究和整合,本文提出了一种新的基于上述两个模型的新模型,该模型反映了多参数对沉积和反弹预测的影响,同时部分经过实验验证,具有一定可靠性。将模型用于GE E3叶片表面颗粒沉积的预测,叶片材料选用RENE41,叶片考虑气膜冷却,并利用自主开发的程序进行了冷却孔构建和网格的自动化生成,数值计算结果表明,颗粒的加入对于流动参数具有明显影响。在计算中针对不同颗粒入射角采用了一个特定的恢复系数CoRm比,通过对比分析发现加入颗粒之后,在叶片尾缘处流体温度和速度都有所增加。基于不同的恢复系数比进行流场及颗粒沉积数值模拟,结果表明恢复系数对流场结果的影响不大。通过结果详细分析了颗粒的运动轨迹,并提出模型的简化必要性。基于前文数值模拟获得的颗粒沉积率分布进行了沉积形貌的构建。根据所得颗粒沉积率的分布数据,通过等比例关系,并以冷却孔径为基础设计了壁面沉积的几何结构。通过对数值模拟结果进行分析,对比了流体流动现象,以及壁面冷却效果,结果表明,颗粒沉积表面的冷却效率比不沉积表面的冷却效率高,也就是说除了在热传递方面的负面影响,颗粒沉积反而可能更有利于冷却气的组织从而获得更高的气膜冷却效果。从流动上来看,主流气体在冷却孔前因为沉积几何体而向上移动,从而将冷却气流压到设计表面。

关键词：涡轮叶片颗粒沉积恢复系数沉积位置

On the Way to Maturity—The CLEO Ⅲ Data Acquisition and Control System

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International Conference on Computing in High Energy and Nuclear Physics 2001年第1期 589-592页

作者： H.Schwarthoff V.frolov 等 CornellUniversity USA UiversityofMinnesota USA

For more than one year the CLEOⅢ experiment at the Cornell electron positron storage ring CESR has accumulated Physics data using a 4 layer silicon vertex detector and a novel ring image Cherenkov detector,along with a conventional Driftchamber ,*** and muon *** the time of CHEP 2001 the experiment has accumulated 10 fb^-1 of data,The readout and monitoring systems control,ca.400000 electronic *** *** quality and component monitoring,run control are only some of the Slow Control tasks that have to be performed. Deploying industry standards such as CORBA(inter-platform communication)Java (remote access via Web browser)and Objectivity(event and constants databse) as building blocks of the computer network has been of central *** oriented design has enabled the seamless integration of the many individual *** our presentation we will describe experiences with this distributed control system and give a report of the measures taken to obtain a high system availability.

关键词： CLEOⅢ实验计算机控制系统数据获取