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Controlling Membrane Phase Separation of Polymersomes for Programmed Drug Release

Chinese Journal of Polymer Science 2022年第9期40卷 1006-1015页

作者： Shuai Chen Erik jan Cornel Jian-Zhong Du Department of Orthopedics Shanghai Tenth People’s HospitalSchool of MedicineTongji UniversityShanghai 200072China Department of Polymeric Materials School of Materials Science and EngineeringTongji UniversityShanghai 201804China

Programmed release of small molecular drugs from polymersomes is of great importance in drug delivery.A significant challenge is to adjust the membrane permeability in a well-controlled ***,we propose a strategy for controlling membrane phase separation by photo-cross-linking of the membrane-forming blocks with different molecular *** synthesized three amphiphilic block copolymers with different membrane-forming blocks,which are poly(ethylene oxide)_(43)-b-poly((ε-caprolactone)_(45)-stat-((α-(cinnamoyloxymethyl)-1,2,3-triazol)caprolactone)_(25))(PEO_(43)-b-P(CL_(45)-stat-CTCL_(25))),PEO_(43)-b-P(CL_(108)-stat-CTCL_(16)),and PEO_(43)-b-PCTCL_(4)-b-PCL_(79).These polymers were self-assembled into polymersomes using either a solvent-switch or powder rehydration method,and the obtained polymersomes were characterized by dynamic light scattering and transmission electron *** the phase separation patterns within the polymersome membranes were investigated by mesoscopic dynamics(MesoDyn)*** further confirm the change of the membrane permeability that resulted from the phase separation within the membrane,doxorubicin,as a small molecular drug,was loaded and released from the *** to the incompatibility between membrane-forming moieties(PCTCL and PCL),phase separation occurs and the release rate can be tuned by controlling the membrane phase pattern or by ***,besides the compacting effect by formation of chemical bonds in the membrane,the cross-linking process can act as a driving force to facilitate the rearrangement and re-orientation of the phase pattern,which also influences the drug release behavior by modulating the cross-membrane distribution of the amorphous PCTCL *** this way,the strategy of focusing on the membrane phase separation for the preparation of the polymersomes with finely tunable drug release rate can be envisioned and designed accordingly,which is of great signifi

关键词： Polymersome Drug delivery Phase separation Programmed drug release

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Language, Conceptualization and TAM Marking： A Cognitive-functional Perspective

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外国语 2009年第1期32卷 2-43页

作者： jan Nuyts University of Antwerp Belgium

At the level of empirical phenomena,this paper deals with the system of 'Tense Aspect Modality' marking or of 'qualificational categories' in *** is this system organized? What are the principles behind it? The major focus is on the modal *** the theoretical level,this paper addresses issues pertaining to the organization and functioning of the cognitive systems involved in language use,with special focus on the differences and correspondences between two major theoretical strands in present day linguistics,viz.'functional linguistics' and 'cognitive linguistics'.

关键词：语言概念化认知功能英语语法

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Mechanical circulatory support in cardiogenic shock and post-myocardial infarction mechanical complications

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Journal of Geriatric Cardiology 2022年第2期19卷 130-136页

作者： Daniel Rob jan Bělohlávek nd Department of Medicine-Department of Cardiovascular Medicine First Faculty of MedicineCharles University and General University HospitalPragueCzech Republic

Despite advanced therapies,the mortality of patients with myocardial infarction(MI)complicated by cardiogenic shock(CS)remains around 50%.Mechanical complications of MI are rare nowadays but associated with high mortality in patients who present with *** treatment strategies and mechanical circulatory support(MCS)devices have been increasingly used to improve the grim prognosis of refractory *** article discusses current evidence regarding the use of MCS in MI complicated by CS,ventricular septal rupture,free wall rupture and acute mitral *** selection should be tailored according to the cause and severity of *** MCS initiation and multidisciplinary team cooperation is mandatory for good *** associated bleeding remains a major complication and an obstacle to better *** prospective randomized trials will improve current knowledge regarding MCS indications,timing,and patient selection in the coming years.

关键词： mortality infarction rupture

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Ability for Self-Pelletization of Iron Ores and Magnetite Concentrates

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Journal of Iron and Steel Research International 2011年第6期18卷 1-7页

作者： Francik Przemysaw jan Mróz Czestochowa University of Technology Czestochowa 42-200Poland

A procedure for evaluating the susceptibility of raw materials for the process of sintering of iron ore mixes is presented. The procedure relies on the evaluation of the amount and quality of the finest grain fraction. The method is based on determination of particular grain fractions. For the grain less than 0.15 mm, the determination of the a- mount is performed using an IPS （Infrared Particles Sizer） grain size analyzer and for the grain larger than 0.15 ram, the fraction is determined using the （wet and dry） screening methods. This allows for quantity assessment of the quality of material in terms of its susceptibility to self-pelletizing by calculating Total Ability for SelPPelletizing （TASP） index fT. The presented method, in combination with the grain size and chemical analyses, can serve for evaluation of suitability of raw material and mixes for the sintering process. Furthermore, the TASP index for 10 types of iron ores and concentrates was determined. The usability of the TASP index was verified by determination of its impact on yield of sintering process both in laboratory and in industry scale.

关键词： iron ore concentrate grain composition pelletization process sintering process productivity

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IGC 2004——Urbino International Workshop to discuss some new concepts in global tectonics

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Episodes 2005年第1期28卷 55-57页

作者： jan Passava GEOCHIM Courses Czech Geological Survey

In the context of the 32^nd International Geological Congress, the University of Urbino which is about to celebrate its 500^th anniversary hosted the post-Congress Workshop PWO-09 from 29^th to 31^st August 2004 dedicated to “New Concepts in Global Tectonics：Emphasis on Some Fundamental Questions in Geology”, convened and organized by Forese Carlo Wezel.

关键词： 2004年世界地质学大会地质构造学术成果成岩作用

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Electrodynamics of Abrikosov vortices： the field theoretical formulation

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Frontiers of physics 2011年第4期6卷 357-369页

作者： Aron J. Beekman jan Zaanen Instituut-Lorentz for Theoretical Physics Universiteit Leiden P. O. Box 9506 2300 RA Leiden The Netherlands

Electrodynamic phenomena related to vortices in superconductors have been studied since their prediction by Abrikosov, and seem to hold no fundamental mysteries. However, most of the effects are treated separately, with no guiding principles. We demonstrate that the relativistic vortex worldsheet in spacetime is the object that naturally conveys all electric and magnetic information, for which we obtain simple and concise equations. Breaking Lorentz invariance leads to down-to-earth Abrikosov vortices, and special limits of these equations include for instance dynamic Meissner screening and the AC Josephson relation. On a deeper level, we explore the electrodynamics of two-form sources in the absence of electric monopoles, in which the electromagnetic field strength itself acquires the characteristics of a gauge field. This novel framework leaves room for unexpected surprises .

关键词： Abrikosov vortex, electromagnetism, Maxwell equations, differential geometry multivalued fields

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Bright trions in direct-bandgap silicon nanocrystals revealed by low-temperature single-nanocrystal spectroscopy

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Light(Science & Applications) 2015年第1期4卷 179-186页

作者： Katerina Kusova Ivan Pelant jan Valenta Institute of Physics of the ASCR v.v.i.Cukrovarnicka 1016200 Prague 6Czech Republic Faculty of Mathematics and Physics Charles UniversityKe Karlovu 512116 Prague 2Czech Republic

Strain-engineered silicon nanocrystals(SiNCs)have recently been shown to possess direct ***,we report the observation of a rich structure in the single-nanocrystal photoluminescence spectra of strain-engineered direct-bandgap SiNCs in the temperature range of 9–300 *** relationship between individual types of spectra is discussed,and the numerical modeling of spectral diffusion of the experimentally acquired spectra reveals a common origin for most *** intrinsic spectral shape is shown to be a structure that contains three peaks,approximately 150 meV apart,each of which possesses a Si phonon *** spectral lines,reaching ≤ meV at 20 K,are *** observed temperature dependence of the spectral structure can be assigned to the radiative recombination of positively charged trions,in contrast to several previous reports linking a very similar shape to phonons in the surface capping *** result serves as strong additional support for the direct-bandgap nature of the investigated SiNCs.

关键词： direct bandgap low-temperature single-nanocrystal spectroscopy silicon nanocrystals trions

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Debris Flows Risk Analysis and Direct Loss Estimation:the Case Study of Valtellina di Tirano,Italy

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Journal of Mountain Science 2014年第2期11卷 288-307页

作者： jan BLAHUT Thomas GLADE Simone STERLACCHINI Department of Engineering Geology Institute of Rock Structure and Mechanics Academy of Sciences of the Czech Republic Geomorphic Systems and Risk Research Group Department of Geography and Regional Research University of Vienna Institute for the Dynamic of Environmental Processes National Research CouncilCNR-IDPA

andslide risk analysis is one of the primary studies providing essential instructions to the subsequent risk management process. The quantification of tangible and intangible potential losses is a critical step because it provides essential data upon which judgments can be made and policy can be formulated. This study aims at quantifying direct economic losses from debris flows at a medium scale in the study area in Italian Central Alps. Available hazard maps were the main inputs of this study. These maps were overlaid with information concerning elements at risk and their economic value. Then, a combination of both market and construction values was used to obtain estimates of future economic losses. As a result, two direct economic risk maps were prepared together with risk curves, useful to summarize expected monetary damage against the respective hazard probability. Afterwards, a qualitative risk map derived using a risk matrix officially provided by the set of laws issued by the regional government, was prepared. The results delimit areas of high economic as well as strategic importance which might be affected by debris flows in the future. Aside from limitations and inaccuracies inherently included in risk analysis process, identification of high risk areas allows local authorities to focus their attention on the “hot-spots”, where important consequences may arise and local （large） scale analysis needs to be performed with more precise cost-effectiveness ratio. The risk maps can be also used by the local authorities to increase population’s adaptive capacity in the disaster prevention process.

关键词： Debris flows Risk analysis Economic losses Central Alps Italy

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Dynamic Actin Controls Polarity Induction de novo in Protoplasts

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Journal of Integrative Plant Biology 2013年第2期55卷 142-159页

作者： Beatrix Zaban jan Maisch Peter Nick Botanical Institute Molecular Cell Biology Karlsruhe Institute of Technology

Cell polarity and axes are central for plant morphogenesis. To study how polarity and axes are induced de novo, we investigated protoplasts of tobacco Nicotiana tabacum cv. BY-2 expressing fluorescently- tagged cytoskeletal markers. We standardized the system to such a degree that we were able to generate quantitative data on the temporal patterns of regeneration stages. The synthesis of a new cell wall marks the transition to the first stage of regeneration, and proceeds after a long preparatory phase within a few minutes. During this preparatory phase, the nucleus migrates actively, and cytoplasmic strands remodel vigorously. We probed this system for the effect of anti-cytoskeletal compounds, inducible bundling of actin, RGD-peptides, and temperature. Suppression of actin dynamics at an early stage leads to aberrant tripolar cells, whereas suppression of microtubule dynamics produces aberrant sausage- like cells with asymmetric cell walls. We integrated these data into a model, where the microtubular cytoskeleton conveys positional information between the nucleus and the membrane controlling the release or activation of components required for cell wall synthesis. Cell wall formation is followed by the induction of a new cell pole requiring dynamic actin filaments, and the new cell axis is manifested as elongation growth perpendicular to the orientation of the aligned cortical microtubules.

关键词： Actin axis formation microtubules polarity induction tobacco BY-2 protoplasts.

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Break of symmetry in regenerating tobacco protoplasts is independent of nuclear positioning

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Journal of Integrative Plant Biology 2016年第9期58卷 799-812页

作者： Linda Brochhausen jan Maisch Peter Nick Molecular Cell Biology Botanical Institute Karlsruhe Institute of Technology Katserstr. 2 D-76133 Karlsruhe Germany

Nuclear migration and positioning are crucial for the morphogenesis of plant cells. We addressed the potential role of nuclear positioning for polarity induction using an experimental system based on regenerating protoplasts, where the induction of a cell axis de novo can be followed by quantification of specific regeneration stages. Using overexpression of fluorescently tagged extranuclear （perinu- clear actin basket, kinesins with a calponin homology domain （KCH）） as well as intranuclear （histone H2B） factors of nuclear positioning and time-lapse series of the early stages of regeneration, we found that nuclear position is no prerequi- site for polarity formation. However, polarity formation and nuclear migration were both modulated in the transgenic lines, indicating that both phenomena depend on factors affecting cytoskeletal tensegrity and chromatin structure. We integrated these findings into a model where retrograde signals are required for polarity induction. These signals travel via the cytoskeleton from the nucleus toward targets at the plasma membrane.

关键词： Axis formation cytoskeleton nuclear migration polarity induction tobacco BY-2 protoplast

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