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Experimental repetitive mild traumatic brain injury induces deficits in trabecular bone microarchitecture and strength in mice

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Bone Research 2017年第4期5卷 357-366页

作者： Chandrasekhar Kesavan nikita M Bajwa Heather Watt Subburaman Mohan Musculoskeletal Disease Center VA Loma Linda Healthcare SystemLama LindaCAUSA Department of Medicine Loma DndaCAUSA Department of Orthopedic Surgery Loma Linda UniversityLoma LindaCAUSA

To evaluate the long-term consequence of repetitive mild traumatic brain injury （mTBI） on bone, mTBI was induced in 10-week-old female C57BL/6J mice using a weight drop model, once per day for 4 consecutive days at different drop heights （0.5, 1 and 1.5 m） and the skeletal phenotype was evaluated at different time points after the impact. In vivo micro-CT （μ-CT） analysis of the tibial metaphysis at 2, 8 and 12 weeks after the impact revealed a 5%-32% reduction in trabecular bone mass. Histomorphometric analyses showed a reduced bone formation rate in the secondary spongiosa ofl.5 m impacted mice at 12 weeks post impact. Apparent modulus （bone strength）, was reduced by 30% （P 〈 0.05） at the proximal tibial metaphysis in the 1.5 m drop height group at 2 and 8 weeks post impact. Ex vivo μ-CT analysis of the fifth lumbar vertebra revealed a significant reduction in trabecular bone mass at 12 weeks of age in all three drop height groups. Serum levels of osteocalcin were decreased by 22%, 15%, and 19% in the 0.5, 1.0 and 1.5 m drop height groups, respectively, at 2 weeks post impact. Serum IGF-I levels were reduced by 18%-32% in mTBI mice compared to control mice at 2 weeks post impact. Serum osteocalcin and IGF-I levels correlated with trabecular BV/TV （r2 = 0.14 and 0.16, P 〈 0.05）. In conclusion, repetitive mTBI exerts significant negative effects on the trabecular bone microarchitecture and bone mechanical properties by influencing osteoblast function via reduced endocrine IGF-I actions.

关键词： IGF TBI Experimental repetitive mild traumatic brain injury induces deficits in trabecular bone microarchitecture and strength in mice

Structural and geochemical features of coal‑bearing sediments and sources of rare element impurities in coals of the Rakovka depression,Primorsky Krai,Russia

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International Journal of Coal Science & Technology 2022年第1期9卷 71-83页

作者： nikita Popov Igor Chekryzhov Irina Tarasenko Sergery Kasatkin Aleksei Kholodov Far East Geological Institute FEB RAS VladivostokRussian Federation

There are known brown coal deposits in Primorsky Krai(Russian Federation),where coals contain rare elements(Ge,U,REE,etc.)up to industrial *** of the known metalliferous coals is the Rakovka coal-bearing depression,located on the southern edge of the Khanka(Prikhankaiskaya)Lowland,with an area of about 70 ***-metal granites with a developed weathering crust are spread in its basement and *** structural conditions forming the depression were studied using measurements of orientations of structural elements(layering,contacts,veins,and dikes)with regard to kinematic conditions of *** coal and host rocks were sampled in sections in the cross strike of the coal *** and dikes cutting them were sampled by separate rock chip *** chemical composition and element content were determined for all *** was found that the adjacent rocks played a major role in the formation of the Rakovka rare-metal-coal *** rare-elements enrichment is not associated with active tectonics,faults,and hydrothermal sources,as was previously ***,it was caused by the hydrogenic and clastogenic removal of these metals from the weathering crust of granites of the depression's flanks and argillated basite dikes cutting the *** hydrogenic nature of the anomalous accumulation of U in sorbed form on organic matter of coals is confirmed by the predominant enrichment of low-ash *** earth elements entered coal seams both in mineral and dissolved forms.A model of REE and uranium input into the coal-bearing sediments of the Rakovka depression was proposed.

关键词： REE Rare metal-coal deposit Accumulation pattern Tectonics

Comparison of CoMoS4/CoMoO4,CoMoS4/CoWO4 and CoMoS4/Co3V2O8 as A New Type of Electrode Materials for Supercapacitors

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Comparison of CoMoS4/CoMoO4,CoMoS4/CoWO4 and CoMoS4/Co3V2O8 ...

作者： SAZONOV nikita 兰州理工大学

学位级别：硕士

由于对环境污染的担心和化石能源的消耗,发展可替代的、并且具备高能量密度和功率密度的能量存储/转换装置具有特殊的意义。在众多电源设备中,超级电容器,也称为电化学电容器(ECs),因为其许多可取的属性,吸引了研究者极大的兴趣。即便如... 详细信息

由于对环境污染的担心和化石能源的消耗,发展可替代的、并且具备高能量密度和功率密度的能量存储/转换装置具有特殊的意义。在众多电源设备中,超级电容器,也称为电化学电容器(ECs),因为其许多可取的属性,吸引了研究者极大的兴趣。即便如此,超级电容器想要作为实际应用的能源装置,仍然需要具备高的能量密度和功率密度.就超级电容器的发展现状及动态而言,金属氧化物电极材料具有较大的发展前景和潜力。但在目前的报道中,对CoMoO,CoWO,CoVO及CoMoS/材料的超级电容性能的研究仍然很少,而且制备方法比较复杂。其次单一的双金属氧化物性能比较单一,各有优缺点。据此,本文设计了以CoMoS为基体,构筑了CoMoS/CoMoO,CoMoS4/CoWO4 and CoMoS/CoVO的复合材料.一、设计制备CoMoS/CoMoO复合材料。采用一步化学法,调控MoO/MoS材料中CoMoS与CoMoO的相对含量,制备出一系列不同形貌的CoMoS/CoMoO电极材料。采用XRD、SEM、TEM-Mapping等测试手段探究MoO/MoS材料的结构形貌特征,分析探CoMoS4/CoMoO4复合电极与纯CoMoS和CoMoO三种电极材料的电化学性能差异.制备的CoMoS/CoMoO纳米复合材料的比电容约为399 F g其倍率性能为80.5%,拥有较好的循环稳定性。二、在研究CoMoS/CoMoO电极材料的基础上,进一步制备并探究CoMoS/CoWO电极材料。采用XRD、SEM、TEM等手段对CoMoS/CoWO进行结构和形貌的表征,同时测试其电化学性能,从电负性发面探讨研究CoMoS/CoWO,CoMoS及CoWO的电化学性能及规律。制备的CoMoS/CoWO纳米复合材料的比电容约为528 F g其倍率性能为78.8%,拥有较好的循环稳定性。三、在研究CoMoS/CoMoO及CoMoS/CoWO等钴钼基电极材料的基础上,进一步探究CoMoS/CoVO电极材料的电化学性能,制备了CoMoS/CoVO,CoVO及CoMoS电极材料,采用XRD、SEM、TEM等手段对三种材料进行结构和形貌的表征,同时测试对比这三种材料的其电化学性能,探讨研复合前后CoMoS/CoVO,CoVO及CoMoS的的电化学性能及规律。制备的CoMoS/CoVO纳米复合材料的比电容约为584 F g其倍率性能为84.1%,拥有较好的循环稳定性。

关键词：超级电容器纳米复合材料 CoMoS4/Co3V2O8 CoMoS4/CoMoO4 CoMoS4/CoWO4

Metabolomic fingerprinting of porcine lung tissue during pre-clinical prolonged ex vivo lung perfusion using in vivo SPME coupled with LC-HRMS

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Journal of Pharmaceutical Analysis 2022年第4期12卷 590-600页

作者： nikita Looby Anna Roszkowska Aadil Ali Barbara Bojko Marcelo Cypel Janusz Pawliszyn Department of Chemistry University of WaterlooWaterlooN2L 3G1Canada Department of Pharmaceutical Chemistry Medical University of Gdansk80-416GdanskPoland Division of Thoracic Surgery University Health NetworkTorontoM5G 2C4Canada Department of Pharmacodynamics and Molecular Pharmacology Faculty of PharmacyCollegium Medicum in BydgoszczNicolaus Copernicus University in Torun85-089BydgoszczPoland

Normothermic ex vivo lung perfusion(NEVLP)has emerged as a modernized organ preservation technique that allows for detailed assessment of donor lung function prior to *** main goal of this study was to identify potential biomarkers of lung function and/or injury during a prolonged(19 h)NEVLP procedure using in vivo solid-phase microextraction(SPME)technology followed by liquid chromatography-high resolution mass spectrometry(LC-HRMS).The use of minimally invasive in vivo SPME fibers for repeated sampling of biological tissue permits the monitoring and evaluation of biochemical changes and alterations in the metabolomic profile of the *** in vivo SPME fibers were directly introduced into the lung and were also used to extract metabolites(on-site SPME)from fresh perfusate samples collected alongside lung samplings.A subsequent goal of the study was to assess the feasibility of SPME as an in vivo method in metabolomics studies,in comparison to the traditional inlab metabolomics *** upregulated biochemical pathways involved in pro-and antiinflammatory responses,as well as lipid metabolism,were observed during extended lung perfusion,especially between the 11th and 12th hours of the procedure,in both lung and perfusate ***,several unstable and/or short-lived metabolites,such as neuroprostanes,have been extracted from lung tissue in vivo using SPME ***-site monitoring of the metabolomic profiles of both lung tissues through in vivo SPME and perfusate samples on site throughout the prolonged NEVLP procedure can be effectively performed using in vivo SPME technology.

关键词： Normothermic ex vivo lung perfusion Solid phase microextraction Lung metabolomics

Tumor cell death visualization of renal cell carcinoma under the combined effect of the Gratiola officinalis extract and cyclophosphamide using fluorescent staining methods

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Journal of Innovative Optical Health Sciences 2021年第5期4卷 46-52页

作者： Artyom Mylnikov nikita Navolokin Dmitry Mudrak Natalya Polukonova Alla Bucharskaya Galina Maslyakova Saratov State Medical University named after V.I.Razumovsky 112 Bolshaya Kazachia Street Saratov 410012Russia National Research Saratov State University 83 Astrakhanskaya Street Saratov 410012Russia National Research Tomsk State University 36 Lenin Avenue Tomsk 634050Russia

Objective of the study:We used fluorescence imaging methods of apoptosis and necrosis in human renal carcinoma A498 tumor cells in vitro to reveal the indicated forms of cell death under the combined effect of flavonoid-containing extract of Gratiola officinalis and cytostatic(cyclo-phosphamide).Materials and methods:The dyes were propidium iodide and acridine orange,which were used in the"alive and dead"*** test helped us to identify the total number of dead cells in the forms of necrosis and apoptosis and the number of cells in which apoptosis had started,it was characterized by the appearance of apoptotic bodies or nucleus ***:We found the most pronounced cytotoxic activity at the ratio of extract of Gratiola officinalis and cyclophosphamide concentrations of 1∶*** number of living cells decreased when exposed to the ratio of extract and cytostatic concentrations of 2∶*** the ratio of concentration of the extract relative to the cytostatic increased to 3∶1,the cytostatic activity of the extract began to appear,the total number of tumor cells *** number of cells with nucleus pyknosis and the number of cells with apoptosis signs significantly increased at a 3∶1 ratio of extract and cytostatic concentrations,which confirms the presence of pro-apoptotic activity of the studied *** trend indicates the dependence of a certain form of cell death(apoptosis,necrosis)on the ratio of extract and cytostatic doses,and it also demon-strates the cytostatic and cytotoxic effects of this ***:Fluorescence methods of investigation in the"alive and dead"test allowed us to visualize the forms of cell death of human kidney carcinoma A498 by combined exposure to the fiavonoid-containing extract of Gratiola officinalis and cytostatic(cyclophosphamide)24 h after *** found that the combination with a concentration ratio of the extract and cyclophosphamide of 3:1 has the greatest effectiveness due to stimulation of t

关键词： A498 cell line Gratiola officinalis extract antitumor activity cytostatic activity flavonoids fluorescent methods kidney cancer

Highly efficient transient stimulated Raman scattering on secondary vibrational mode of BaWO_(4) crystal due to its constructive interference with self-phase modulation

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Chinese Optics Letters 2023年第3期21卷 113-117页

作者： Igor Kinyaevskiy Valeri Kovalev Pavel Danilov nikita Smirnov Sergey Kudryashov Andrey Koribut Andrey Ionin P.N.Lebedev Physical Institute of the Russian Academy of Sciences Moscow 119991Russia

An exceptionally high stimulated Raman scattering[SRS]conversion efficiency to the first Stokes component associated with the secondary[low-frequency and low intensity]vibrational mode v2[~330 cm^[-1]]was observed in a BaWO4 crystal in a highly transient regime of *** effect takes place in the range of pump pulse energy from~0.1 to~0.5μJ with maximum energy conversion efficiency up to 35%at 0.2μ*** nature of the observed effects is explained by interference of SRS and self-phase modulation,where the latter is related to a noninstantaneous orientational Kerr nonlinearity in the BaWO4 crystal.

关键词： stimulated Raman scattering secondary vibrational mode self-phase modulation ultrashort laser pulses transient phenomena

Comprehensive DDoS Attack Classification Using Machine LearningAlgorithms

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Computers, Materials & Continua 2022年第10期73卷 577-594页

作者： Olga Ussatova Aidana Zhumabekova Yenlik Begimbayeva Eric T.Matson nikita Ussatov Al-Farabi Kazakh National University Almaty050040Kazakhstan Institute of Information and Computational Technologies Almaty050010Kazakhstan Satbayev University Almaty050013Kazakhstan Purdue University West Lafayette47907INUSA Turan University Almaty050013Kazakhstan

The fast development of Internet technologies ignited the growthof techniques for information security that protect data, networks, systems,and applications from various threats. There are many types of threats. Thededicated denial of service attack (DDoS) is one of the most serious andwidespread attacks on Internet resources. This attack is intended to paralyzethe victim’s system and cause the service to fail. This work is devoted tothe classification of DDoS attacks in the special network environment calledSoftware-Defined Networking (SDN) using machine learning algorithms. Theanalyzed dataset included instances of two classes: benign and *** the dataset contained twenty-two features, the feature selection techniques were required for dimensionality reduction. In these experiments, theInformation gain, the Chi-square, and the F-test were applied to decreasethe number of features to ten. The classes were also not completely balanced, so undersampling, oversampling, and synthetic minority oversampling(SMOTE) techniques were used to balance classes equally. The previousresearch works observed the classification of DDoS attacks applying variousfeature selection techniques and one or more machine learning ***, they did not pay much attention to classifying the combinations offeature selection and balancing methods with different machine learningalgorithms. This work is devoted to the classification of datasets with eightmachine learning algorithms: naïve Bayes, logistic regression, support vectormachine, k-nearest neighbors, decision tree, random forest, XGBoost, andCatBoost. In the experimental results, the Information gain and F-test featureselection methods achieved better performance with all eight ML algorithmsthan with the Chi-square technique. Furthermore, the accuracy values of theoversampled and SMOTE datasets were higher than that of the undersampledand imbalanced datasets. Among machine learning algorithms, the accuracyof support vector

关键词： Internet security networks systems DDoS software-defined networking feature selection class balancing machine learning XGBoost CatBoost

Energetic Abilities of Solid Composite Propellants Based on 3,4,5-Trinitropyrazole and Ammonium Dinitramide

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火炸药学报 2016年第3期39卷 17-20页

作者： LEMPERT David B. CHUKANOV nikita SHU Yuan-jie Institute of Problems of Chemical Physics Russian Academy of SciencesMoscow 142432Russia Xi′an Modern Chemistry Research Institute Xi′an 710065China

The investigation aims at the expansion of the basis of formulations of solid composite propellants by introducing new compositions with lower sensitivity to mechanic impact and improved thermal *** formulations based on trinitropyrazole(TNP)contains a binder(a hydrocarbon or active one),aluminum and inorganic oxidizer *** results show that a binary formulation TNP+active binder(18%-19%)(volume fraction)with no metal is well designed which would achieve high specific impulse(at Pc∶Pa=40∶1)of 248s,high density of 1.80g/cm3 and combustion temperature Tcabout 3 *** terms of energy,metal-free compositions with TNP lose a bit to those with HMX,only if HMX fraction in formulation is higher than 45%-50%.

关键词： solid composite propellants specific impulse 3,4,5-trinitropyrazole TNP binder ammonium dinitramide ADN

Review of biosensing with whispering-gallery mode lasers

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Light(Science & Applications) 2021年第3期10卷 352-370页

作者： nikita Toropov Gema Cabello Mariana P.Serrano Rithvik R.Gutha Matias Rafti Frank Vollmer Departm ent of Physics and Astronomy Living Systems InstituteUniversity of ExeterExeter EX44QDUK Departamento de Qulmica Instituto de Investigaciones Fisicoqufmicas Teoricas y AplicadasUniversidad Nacional de La PlataLa Plata 1900Argentina

Lasers are the pillars of modern optics and *** based on whispering-gallery modes(WGMs)are miniature in size and have excellent lasing characteristics suitable for *** lasers have been used for labelfree detection of single virus particles,detection of molecular electrostatic changes at biointerfaces,and barcode-type live-cell tagging and *** most recent advances in biosensing with WGM microlasers are described in this *** cover the basic concepts of WGM resonators,the integration of gain media into various active WGM sensors and devices,and the cutting-edge advances in photonic devices for micro-and nanoprobing of biological samples that can be integrated with WGM lasers.

关键词： lasers Lasers mode