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Germination of Chenopodium Album in Response to Microwave Plasma Treatment

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Plasma Science and Technology 2008年第4期10卷 506-511页

作者： Bo■ena er Vitězslav STRA■k Michal er■ Milan TICH■ Petr PATENkA Institute of Systems Biology and Ecology Academy of Sciences of the Czech RepublicNa Sádkách 7CZ-370 05eské BudějoviceCzech Republic University of South Bohemia in eské Budějovice Department of PhysicsJeronymova 10CZ-371 15 eské BudějoviceCzech Republic Charles University in Prague Faculty of Mathematics and PhysicsV Holeovikách 2CZ-180 00 Praha 8Czech Republic University of South Bohemia in eské Budějovice Department of PhysicsJeronymova 10 CZ-371 15 eské BudějoviceCzech Republic Technical University of LiberecDepartment of Material SciencesHáIkova 6CZ-461 17 Liberec iCzech Republic

The seeds of Lamb＇s Quarters （Chenopodium album agg.） were stimulated by low- pressure discharge. The tested seeds were exposed to plasma discharge for different time durations （from 6 minutes to 48 minutes）. Germination tests were performed under specified laboratory conditions during seven days in five identical and completely independent experiments. Significant differences between the control and plasma-treated seeds were observed. The treated seeds showed structural changes on the surface of the seat coat. They germinated faster and their sprout accretion on the first day of seed germination was longer. Germination rate for the untreated seeds was 15% while it increased approximately three times （max 55%） for seeds treated by plasma from 12 minutes to 48 minutes.

关键词： early growth germination Lamb's Quarters seed enhancement stimulation surfatron discharge

Spatiotemporal analysis of elastic and inelastic deformations in roof-rocks from seismological observations

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International Journal of Mining Science and Technology 2021年第2期31卷 241-251页

作者： Maciej JMendecki RafałPakosz Łukasz Wojtecki wacław MZuberek faculty of Environmental Sciences the University of Silesia in Katowice41-200 SosnowiecPoland Polish Mining Group 40-039 KatowicePoland Central Mining Institute 40-166 KatowicePoland

The spatiotemporal analysis of seismic zones characterised by the scattering and accumulation of strain energy in the roof-rocks of the excavated longwall panel where inelastic or elastic deformations occurred during hard coal seam mining is *** studied longwall panel was designed to utilize the effect of partial stress relaxation caused by the earlier extraction of the coal seams located above.A full seismic moment tensor and spectral source parameter analyses were used to obtain information about the degree of inelastic and elastic coseismic *** study also showed that these deformation changes correspond to variation in the Benioff strain release ***,analyses of deformation zones were compared with the relationship between radiated energy and the excavated volume of rocks per *** concept of balanced seismic energy release assumed the exponential increase of released seismic energy with the increase in the volume of excavated *** between the observed and predicted radiated energies indicated that strain energy in selected zones in the rock mass was either scattered if the prediction was overestimated,or accumulated if ***,the study showed that elastic deformation in one zone can lead to inelastic deformation in the same zone.

关键词： Mining seismicity Seismic source volume Apparent volume Hard coal mine Longwall mining Benioff strain

Sedimentary and environmental history of the Late Permian Bonikowo Reef(Zechstein Limestone, Wuchiapingian), western Poland

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Journal of Palaeogeography 2017年第3期6卷 183-205页

作者： Pawe? Raczyński Tadeusz Marek Peryt wac?aw Strobel Institute of Geological Sciences University of Wroc?aw Polish Geological Instituted-National Research Institute Institute of Agrophysics Polish Academy of Sciences

The Bonikowo Reef occurs in the central part of the Zechstein Limestone Basin in western Poland and was growing on the topmost edges of tilted blocks and/or on the top of uplifted horsts of the BrandenburgeWolsztynePogorzela High. Its size is ca. 1.6 km^2. The Bonikowo Reef shows the thickest reef section（90.5 m） recorded in the High. The Zechstein Limestone unit is represented mostly by limestones, often thoroughly recrystallized, although the macrotextures and biota of the boundstone are identifiable in most cases. The drillcore section is a mixture of boundstones（microbial and bryozoan）, wackestones, packstones and grainstones, which often co-occur. The δ^13 C and δ^18 O values for both calcite（avg. 3.8 ± 0.8‰ and-3.4 ± 1.7‰, respectively） and dolomite（avg. 3.5 ± 0.7‰ and-5.2 ± 1.3‰, respectively） are transitional between the values previously reported for condensed sequences of the basinal facies and larger reef complexes. The biofacies of the Bonikowo Reef are very similar to those recognized in other reefs of the BrandenburgeWolsztynePogorzela High, which owe their origin to the destruction of bryozoan boundstones. The biota composition is typical and characteristic of other Zechstein Limestone reefs. However, the Bonikowo Reef demonstrates the importance of microbialites, laminar and nodose encrustations, in the growth and cohesion of the Zechstein Limestone reefs. Such encrustations abound within the Zechstein Limestone although, in many cases, the real nature of the encrustations is difficult to ascertain. These laminated encrustations show great similarity to Archaeolithoporella that is one of the most important Permian reefbuilding organisms. The encrustations considered to represent Archaeolithoporella were also previously recorded in the Zechstein Limestone of western Poland and in its stratigraphic equivalent, the Middle Magnesian Limestone of Northeast England. The lower part of the sequence shows great biofacies variability that reflects common envir

关键词： Bonikowo Reef Zechstein Limestone Wuchiapingian Biofacies Carbon and oxygen isotopes

Regression analysis of squeezing-induced hybrid nanofluid flow in Darcy-forchheimer porous medium

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 193-208页

作者： k.MUHAMMAD M.SARfRAZ Department of Humanities and Sciences School of Electrical Engineering and Computer Science National University of Sciences and Technology Department of Mathematics Quaid-i-Azam University

This article presents a mathematical model addressing a scenario involving a hybrid nanofluid flow between two infinite parallel plates. One plate remains stationary, while the other moves downward at a squeezing velocity. The space between these plates contains a Darcy-forchheimer porous medium. A mixture of water-based fluid with gold(Au) and silicon dioxide(Si O2) nanoparticles is formulated. In contrast to the conventional fourier's heat flux equation, this study employs the Cattaneo-Christov heat flux equation. A uniform magnetic field is applied perpendicular to the flow direction, invoking magnetohydrodynamic(MHD) effects. further, the model accounts for Joule heating, which is the heat generated when an electric current passes through the fluid. The problem is solved via NDSolve in MATHEMATICA. Numerical and statistical analyses are conducted to provide insights into the behavior of the nanomaterials between the parallel plates with respect to the flow, energy transport, and skin *** findings of this study have potential applications in enhancing cooling systems and optimizing thermal management strategies. It is observed that the squeezing motion generates additional pressure gradients within the fluid, which enhances the flow rate but reduces the frictional drag. Consequently, the fluid is pushed more vigorously between the plates, increasing the flow velocity. As the fluid experiences higher flow rates due to the increased squeezing effect, it spends less time in the region between the plates. The thermal relaxation, however, abruptly changes the temperature, leading to a decrease in the temperature fluctuations.

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一种基于柱面镜聚焦系统的高灵敏度全谱光谱仪

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光谱学与光谱分析 2025年第1期45卷 222-230页

作者：陈吉文陈作儿赵迎北方工业大学电气与控制工程学院北京100144

很多元素的最灵敏谱线主要分布在紫外波段。一些常被作为检测对象的重要元素,例如C、P和S,其谱线甚至位于200 nm以下的真空紫外波段。然而真空紫外波段内的辐射极易受空气吸收而无法在空气中传输。因此为了适用于紫外波段各谱线的检测,... 详细信息

很多元素的最灵敏谱线主要分布在紫外波段。一些常被作为检测对象的重要元素,例如C、P和S,其谱线甚至位于200 nm以下的真空紫外波段。然而真空紫外波段内的辐射极易受空气吸收而无法在空气中传输。因此为了适用于紫外波段各谱线的检测,常使用光程短、系统精简的罗兰圆光学系统作为光谱仪的色散系统,并且在进行检测分析时,还需对设备腔体内部建立相对真空的环境进行实验,进而减小实验环境对真空紫外波段内各谱线强度的削弱作用。然而即使在该条件下,P和S这两种元素在真空紫外波段的谱线灵敏度仍然较弱。为此为了实现真空紫外波段范围内的高灵敏度,本研究在距离像面前30 mm处位置设计了一个柱面镜聚焦系统。其采用了材料为Caf_(2)、中心厚度为5 mm以及弧矢面曲率半径为22.06 mm的柱面镜作为核心部件。并利用仿真软件Zemax对设计的光学系统进行仿真与优化,以及从非序列模式下的辐射照度仿真结果可知,柱面镜聚焦系统在几乎不影响分辨率的情况下对各波长成像灵敏度有较大的提升。最后以中低合金钢为检测样品,使用电火花激发光源对样品中各元素在紫外波段内的各谱线进行激发,进而验证光谱仪的各项性能:通过一次拟合、参比拟合以及二次拟合,建立每个元素谱峰强度和实际含量之间的数学模型,并算得各元素的拟合优度R^(2)均在0.99以上;柱面镜聚焦系统显著提高了设备在真空紫外波段的灵敏度,响应提高了1倍以上。实验结果表明,柱面镜聚焦系统的设计方法对于提升罗兰圆色散系统的灵敏度具有一定的参考价值。

关键词：紫外光谱罗兰圆光学系统柱面镜灵敏度拟合优度

On differences between deterministic and statistical models of the interphase region

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Acta Mechanica Sinica 2022年第8期38卷 73-88页

作者： Tomasz wacławczyk faculty of Power and Aeronautical Engineering Warsaw Univesity of TechnologyWarsaw00-665Poland

This paper reviews differences between the deterministic(sharp and diffuse)and statistical models of the interphase region between the *** the literature this region is usually referred to as the(macroscopic)***,the mesoscopic interface that is defined at the molecular level and agitated by the thermal fluctuations is found with nonzero *** this reason,in this work,the interphase region is called the mesoscopic intermittency/transition *** this purpose,the first part of the present work gives the rationale for introduction of the mesoscopic intermittency region statistical *** is argued that classical(deterministic)sharp and diffuse models do not explain the experimental and numerical results presented in the ***,it is elucidated that a statistical model of the mesoscopic intermittency region(SMIR)combines existing sharp and diffuse models into a single coherent framework and explains published experimental and numerical *** the second part of the present paper,the SMIR is used for the first time to predict equilibrium and nonequilibrium two-phase flow in the numerical *** this goal,a two-dimensional rising gas bubble is studied;obtained numerical results are used as a basis to discuss differences between the deterministic and statistical models showing the statistical description has a potential to account for the physical phenomena not previously considered in the computer simulations.

关键词： Multiphase flow Phase field and level-set methods Area density model Statistical interface model Nonequilibrium phenomena in two-phase flow

siRNA therapeutics:a clinical reality

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Science China(Life Sciences) 2020年第4期63卷 485-500页

作者： Phei er Saw er-Wei Song Guangdong Provincial key Laboratory of Malignant Tumor Epigenetics and Gene Regulation Sun Yat-Sen Memorial HospitalSun Yat-Sen UniversityGuangzhou 510120China Breast Tumor Center Sun Yat-Sen Memorial HospitalSun Yat-Sen UniversityGuangzhou 510120China Zhongshan School of Medicine Breast SurgeryGuangzhou 510080China

Since the revolutionary discovery of RNA interference(RNAi),a remarkable progress has been achieved in understanding and harnessing gene silencing mechanism;especially in small interfering RNA(siRNA)*** its tremendous potential benefits,major challenges in most siRNA therapeutics remains unchanged-safe,efficient and target oriented delivery of *** years after the discovery of RNAi,siRNA therapeutics finally charts its way into *** we journey through the decades,we reminisce the history of siRNA discovery and its application in a myriad of disease ***,we highlight the breakthroughs in si RNA therapeutics,with special feature on the first fDA approved RNAi therapeutics Onpattro(Patisiran)and the consideration of effective siRNA delivery system focusing on current siRNA nanocarrier in clinical ***,we present some challenges and multiple barriers that are yet to be fully overcome in siRNA therapeutics.

关键词： siRNA therapeutic disease treatment systemic siRNA delivery clinical application

Microstructure,Properties and Wear Behaviors of (Ni_3Al)_p Reinforced Cu Matrix Composites

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Journal of Materials Science & Technology 2011年第10期27卷 937-943页

作者： Ibrahim elikyrek Nese .krpe Tugba ler Remzi Grler Metallurgical and Materials Engineering Department Faculty of Engineering and ArchitectureEski sehir Osmangazi University Institute of Metallurgy Eski sehir Osmangazi University

Pure copper and its composites reinforced with Ni3Al particles were produced by powder metallurgy （PM）. Ni3Al powders were produced by mechanical ball milling from vacuum arc melted compounds. The Ni3Al powders were characterized by X-ray diffraction （XRD）. The microscopy examinations revealed that the Ni3Al particles were distributed uniformly in the matrix. The effects of the particle fraction on the density, electrical conductivity, strength and dry sliding wear resistance of composite were investigated. It was found that the density and electrical conductivity of the composites decrease while the compression yield strength and wear resistance of composites increase with an increase in the particle fraction. The dry sliding wear tests were performed with pin-on-disk geometry. After sliding wear tests, the worn surfaces were examined by scanning electron microscopy （SEM） equipped with an energy dispersive X-ray spectrometer （EDS）. Results have shown that the wear mechanism is oxidative and adhesive.

关键词： Metal matrix composites Powder metallurgy Wear Intermetallics

Effects of P301L-TAU on post-translational modifications of microtubules in human iPSC-derived cortical neurons and TAU transgenic mice

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Neural Regeneration Research 2025年第8期20卷 2348-2360页

作者： Mohamed Aghyad Al kabbani Christoph köhler Hans Zempel Institute of Human Genetics Faculty of Medicine and University Hospital CologneUniversity of CologneCologneGermany Center for Molecular Medicine Cologne(CMMC) University of CologneCologneGermany Center Anatomy Department ⅡMedical FacultyUniversity of CologneCologneGermany

TAU is a microtubule-associated protein that promotes microtubule assembly and stability in the *** is missorted and aggregated in an array of diseases known as *** are essential for neuronal function and regulated via a complex set of post-translational modifications,changes of which affect microtubule stability and dynamics,microtubule interaction with other proteins and cellular structures,and mediate recruitment of microtubule-severing *** impairment of microtubule dynamics causes neuronal dysfunction,we hypothesize cognitive impairment in human disease to be impacted by impairment of microtubule *** therefore aimed to study the effects of a disease-causing mutation of TAU(P301L)on the levels and localization of microtubule post-translational modifications indicative of microtubule stability and dynamics,to assess whether P301L-TAU causes stability-changing modifications to *** investigate TAU localization,phosphorylation,and effects on tubulin post-translational modifications,we expressed wild-type or P301L-TAU in human MAPT-kO induced pluripotent stem cell-derived neurons(i Neurons)and studied TAU in neurons in the hippocampus of mice transgenic for human P301L-TAU(p R5 mice).Human neurons expressing the longest TAU isoform(2N4R)with the P301L mutation showed increased TAU phosphorylation at the AT8,but not the p-Ser-262 epitope,and increased polyglutamylation and acetylation of microtubules compared with endogenous TAU-expressing neurons.P301L-TAU showed pronounced somatodendritic presence,but also successful axonal enrichment and a similar axodendritic distribution comparable to exogenously expressed 2N4R-wildtype-TAU.P301L-TAU-expressing hippocampal neurons in transgenic mice showed prominent missorting and tauopathy-typical AT8-phosphorylation of TAU and increased polyglutamylation,but reduced acetylation,of microtubules compared with non-transgenic *** sum,P301L-TAU results in changes in micr

关键词： human induced pluripotent stem cell microtubules P301L pR5 mice TAU tauopathy tubulin code