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Nanocarriers to Enhance Solubility, Bioavailability, and Efficacy of Artemisinins

World Journal of Traditional chinese Medicine 2020年第1期6卷 26-38页

作者： Anna Rita Bilia Maria camilla Bergonzi Joelle cBoulos thomas Efferth Department of chemistry University of FlorenceFlorenceItaly Department of Pharmaceutical Biology Institute of Pharmacy and BiochemistryJohannes Gutenberg UniversityMainzGermany

The therapeutic potential of artemisinin (ART) and its derivatives (ARTs) is not limited to malaria but has been recently expanded to other infections with protozoans, trematodes, or viruses as well as to cancer. Due to their limited poor water and oil solubility, rapid degradation by the liver, and short half-life, they have a low bioavailability after oral administration. consequently, there is a pressing necessity to formulate new ART preparations to raise its bioavailability and efficacy. Nanosized drug delivery systems represent important tools in modern medicine with wide clinical applications, because of their potential modulation of pharmacokinetic and biodistribution. This review focuses on polymer-based systems, lipid-based systems, and inorganic nanoparticles loaded with ARTs. The overall goal of this field of research is to enhance their solubility and stability to improve bioavailability at much lower doses and to increase long-term safety. In addition, the opportunity to reach highly specific site-targeted delivery by these nanocarriers confers a high medicinal value. Remarkably, most of the reported nanoparticulate drug delivery systems are biologically inactive or marginally immunogenic, generating no antigenic or pyrogenic reactions but only partial intrinsic toxicity. As clinical studies in human patients are available so far, there is a pressing need to translate preclinical results on ART-based nanosystems into clinical settings.

关键词： Artemisinin Asteraceae derivatives inorganic nanocarriers lipid nanocarriers nanotechnology polymeric nanocarriers sesquiterpene lactones

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基于频谱细化算法的电泳光散射Zeta电位测量方法

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光学学报 2017年第2期37卷 284-290页

作者：刘伟张珊珊 John c thomas 陈文钢王雅静申晋山东理工大学电气与电子工程学院山东淄博255049 Group Scientific Pty Ltd. 南澳大利亚州葛兰许5022

电泳光散射法测量Zeta电位时,散射光频移只有几百赫兹,在全频段求取散射光功率谱会降低频率分辨率。为此,提出先用傅里叶变换在全频段对散射光信号进行频谱估计,获取需要细化分析的频谱范围,然后用线性调频变换频谱细化算法在窄带范围... 详细信息

电泳光散射法测量Zeta电位时,散射光频移只有几百赫兹,在全频段求取散射光功率谱会降低频率分辨率。为此,提出先用傅里叶变换在全频段对散射光信号进行频谱估计,获取需要细化分析的频谱范围,然后用线性调频变换频谱细化算法在窄带范围内进行高分辨率的频谱细化分析,从而获得准确的散射光频移。设计了基于激光多普勒技术的散射光频移测量装置,使用该方法分别测量了3种标准聚苯乙烯乳胶微球的Zeta电位。实验结果表明,线性调频变换频谱细化算法可以有效地提高Zeta电位的测量精度,测量重复性小于5%。

关键词：散射电泳光散射 Zeta电位光拍功率谱

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双峰分布颗粒体系的多角度动态光散射数据反演（英文）

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光子学报 2017年第2期46卷 121-132页

作者：徐敏申晋朱新军 thomas John c cLEMENTI Luis A VEGA Jorge R 山东理工大学电气与电子工程学院山东淄博255049 天津工业大学电气工程与自动化学院天津300387 Group Scientific Pty Ltd 23 Pine Lodge Crescent Institute of Technological Development for the chemical Industry(INTEc UNL-CONICET)

采用多角度动态光散射和加权正则化反演方法,对4组模拟的双峰分布颗粒体系(100/600nm,200/600nm,300/600nm和350/600nm)分别选取1、3、6和10个散射角进行测量.粒度反演结果表明,采用加权正则化方法反演双峰颗粒体系的多角度动态光散射... 详细信息

采用多角度动态光散射和加权正则化反演方法,对4组模拟的双峰分布颗粒体系(100/600nm,200/600nm,300/600nm和350/600nm)分别选取1、3、6和10个散射角进行测量.粒度反演结果表明,采用加权正则化方法反演双峰颗粒体系的多角度动态光散射测量数据,可获得峰值位置比小于2∶1且含有大粒径(>350nm)颗粒的双峰颗粒粒度分布.采用标准聚苯乙烯乳胶颗粒进行实测的结果验证了这一结论.得到含大粒径颗粒的双峰粒度分布反演结果的原因在于,多角度动态光散射能提供更多的大粒径颗粒的粒度信息,加权正则化反演方法能减少测量数据中的噪声,因而多角度动态光散射测量数据的加权反演能实现峰值位置比小于2∶1且含有大粒径颗粒的双峰颗粒体系的测量.

关键词：动态光散射粒度分布加权约束正则化峰值位置比吉洪诺夫正则化

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Ageing behaviour of a polyethylene blend:influence of chemical defects and morphology on charge transport

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High Voltage 2020年第3期5卷 270-279页

作者： Somyot Tantipattarakul Alun S.Vaughan thomas Andritsch Tony Davies High Voltage Laboratory University of SouthamptonSouthamptonSO171BJUK Maintenance Division Electricity Generating Authority of ThailandNonthaburiThailand

Abstract:The properties of novel cable insulation systems will rely critically upon the morphology of the ***,a blend of high and low-density polyethylene(PE)was processed in order to generate three sets of samples with different *** influence of thermo-oxidative ageing at 120℃ was then *** resulting chemical changes included the introduction of unsaturation and oxygen-containing groups and were determined by antioxidant consumption and oxygen *** chemical defects were found to be concentrated in the fraction of each system that was molten at 120°c and,consequently,served to inhibit recrystallisation following *** resulting spatial distribution of charge trapping sites was therefore strongly dependent on *** electrical conductivity of each system varied non-monotonically with ageing:short times reduced the conductivity;a rapid increase in conductivity over five orders of magnitude occurred beyond a critical ageing *** the pronounced structural differences between the morphologically distinct sets of samples,all exhibited comparable conductivity values beyond this threshold,implying that while charge transport is strongly influenced by chemical factors,crystallinity is relatively *** experimental finding appears at odds with theoretical studies of the electronic states in crystalline and amorphous PE.

关键词： charge chemical conductivity

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Shear design of high strength concrete prestressed girders

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Frontiers of Structural and civil Engineering 2014年第4期8卷 373-387页

作者： Emad L. LABIB Hemant B. DHONDE thomas T. c. HSU Y. L. MO Oil Field Development Engineering LLc Houston TX 77079 USA Department of civil Engineering VIIT University of Pune Pune 411007 India Department of civil and Environmental Engineering University of Houston Houston TX 77004 USA

Normal strength prestressed concrete I-girders are commonly used as the primary superstructure components in highway bridges. However, shear design guidelines for high strength Pc girders are not available in the current structural codes. Recently, ten 7.62 m （25 feet） long girders made with high strength concrete were designed, cast, and tested at the University of Houston （UH） to study the ultimate shear strength and the shear concrete contribution （Vc） as a function of concrete strength （f＇c）. A simple semi-empirical set of equations was developed based on the test results to predict the ultimate shear strength of prestressed concrete I-girders. The UH-developed set of equations is a function of concrete strength （√f＇c）, web area （bwd）, shear span to effective depth ratio （a/d）, and percentage of transverse steel （Pt）. The proposed UH-Method was found to accurately predict the ultimate shear strength of Pc girders with concrete strength up to 117 MPa （17000 psi） ensuring satisfactory ductility. The UH-Method was found to be not as overly conservative as the AcI-318 （2011） code provisions, and also not to overestimate the ultimate shear strength of high strength Pc girders as the AASHTO LRFD （2010） code provisions. Moreover, the proposed UH-Method was found fairly accurate and not exceedingly conservative in predicting the concrete contribution to shear for concrete strength up to 117 MPa （17000 psi）.

关键词： shear design high strength concrete prestressed girders full-scale tests

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Effects of fluctuating thermal regimes on cold survival and life history traits of the spotted wing Drosophila(Drosophila suzukii)

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Insect Science 2020年第2期27卷 317-335页

作者： thomas Enriquez David Ruel Maryvonne charrier Herve colinet cNRS ECOBIO-UMR 6553Universite de RennesRennesFrance Department of Entomology The Robert H.Smith Faculty of AgricultureFood and EnvironmentThe Hebrew University of JerusalemPO 12Rchovot 76100Isael

Drosophila suzukii is an invasive pest causing severe damages to a large panel of cultivated *** facili tate its biocontrol with stratcgies such as sterile or incompatible insect techniques,*** must be mass-produced and then stored and transported under low *** cold exposure induces chill injuries that can be mitigated if the cold period is interrupted with short warming intervals,referred to as fluctuating thermal regimes(FTR).In this study,we tested how to optimally use FTR to extend the shelf life of *** under cold *** FTR parameters were asessed:temperature(15,20,25℃),duration(0.5,1,2,3 h),and frequency(every 12,24,36,48 h)of warming intervals,in two wild-type lines and in two developmental stages(pupac and adults).Generally,FTR improved cold storage tolerance with respect to constant low temperatures(cLT).cold mortality was lower when recovery temperature was 20℃ or higher,when duration was 2 h per day or longer,and when warming interruptions occurred frequently(every 12 or 24 h).Applying an optimized FTR protocol to adults greatly reduced cold mortality over long-term storage(up to 130 d).consequences of FTR on fitness-related traits were also *** adults,poststorage survival was unaffected by FTR,as was the case for female fecundity and male mating *** the other hand,when cold storage occurred at pupal stage,postorage survival and male mating capacity were altered under cLT,but not under *** storage of pupae,female fecundity was lower under FTR compared to cLT,suggesting an energy trade-off between repair of chill damages and c22 *** study provides detailed information on the application and optimization of an FTR-based protocol for cold storage of *** that could be useful for the biocontrol of this pest.

关键词： cold storage fluctuating thermal regines lfe-history traits recovery sotted wing drosophila

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Trabecular Plate Loss and Deteriorating Elastic Modulus of Femoral Trabecular Bone in Intertrochanteric Hip Fractures

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Bone Research 2013年第4期1卷 346-354页

作者： Ji Wang Bin Zhou Ian Parkinson c.David L.thomas John G.clement Nick Fazzalari X.Edward Guo Bone Bioengineering Laboratory Department of Biomedical EngineeringColumbia UniversityNew YorkNew York 10027USA Bone and Joint Research Lab SA Pathology and Discipline of Anatomy and PathologyUniversity of AdelaideAdelaideAustralia Section of Oral Anatomy and Surgery The Melbourne Dental SchoolUniversity of MelbourneVictoria 3010Australia

Osteoporotic hip fracture is associated with significant trabecular bone loss, which is typically characterized as low bone density by dual-energy X-ray absorptiometry （DXA） and altered microstructure by micro-computed tomography （pcT）. Emerging morphological analysis techniques, e.g. individual trabecula segmentation （ITS）, can provide additional insights into changes in plate-like and rod-like trabeculae, two major micro- structural types serving different roles in determining bone strength. Using ITS, we evaluated trabecular microstructure of intertrochanteric bone cores obtained from 23 patients undergoing hip replacement surgery for intertrochanteric fracture and 22 cadaveric controls. Micro-finite element （~FE） analyses were performed to further understand how the abnormalities seen by ITS might translate into effects on bone strength. ITS analyses revealed that, near fracture site, plate-like trabeculae were seriously depleted in fracture patients, but trabecular rod volume was maintained. Besides, decreased plate area and rod length were observed in fracture patients. Fracture patients also showed decreased elastic moduli and shear moduli of trabecular bone. These results provided evidence that in intertrochanteric hip fracture, preferential loss of plate-like trabeculae led to more rod-like microstructure and deteriorated mechanical competence adjacent to the fracture site, which increased our understanding of the biomechanical pathogenesis of hip fracture in osteoporosis.

关键词： hip fracture intertrochanteric microstructure individual trabecula segmentation finite element

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Fabrication of Polymeric Visual Decoys for the Male Emerald Ash Borer （Agrilus planipennis）

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Journal of Bionic Engineering 2013年第2期10卷 129-138页

作者： Drew P. Pulsifer Akhlesh Lakhtakia Mahesh S. Narkhede Michael J. Domingue Beverly G. Post Jayant Kumar Raul J. Martln-Palma thomas c. Baker Department of Engineering Science & Mechanics Pennsylvania State University University Park Pennsylvania 16802 USA center for Advanced Materials and Department of Plastics Engineering University of Massachusetts Lowell Lowell MA 01854 USA Department of Entomology Pennsylvania State University University Park PA 16802 USA center for Advanced Materials and Department of Physics & Applied Physics University of Massachusetts Lowell Lowell MA 01854 USA Department of Materials Science & Engineering Pennsylvania State University University Park Pennsylvania 16802 USA

Through a bioreplication approach, we have fabricated artificial visual decoys for the invasive species Agrilus planipen- nis--commonly known as the Emerald Ash Borer （EAB）. The mating behavior of this species involves an overflying EAB male pouncing on an EAB female at rest on an ash leaflet before copulating. The male spots the female on the leaflet by visually detecting the iridescent green color of the female＇s elytra. As rearing EAB and then deploying dead females as decoys for trapping is both arduous and inconvenient, we decided to fabricate artificial decoys. We used a dead female to make a negative die of nickel and a positive die of epoxy. Decoys were then made by first depositing a quarter-wave-stack Bragg reflector on a polymer sheet and then stamping it with a pair of matched negative and positive dies to take the shape of the upper surface of an EAB female. As nearly 100 artificial decoys were fabricated from just one EAB female, this bioreplication process is industrially scalable. Preliminary results from a field trapping test are indicative of success.

关键词： bioreplication conformal-evaporated-film-by-rotation method electroforming negative die positive die stampingcopyright ~ 2013 Jilin University. Published by Science Press and Elsevier Limited. All rights reserved.

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How will climate change affect the potential distribution of Eurasian tree sparrows Passer montanus in North America？

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current Zoology 2011年第5期57卷 648-654页

作者： Jim GRAHAM catherine JARNEVIcH Nick YOUNG Greg NEWMAN thomas STOHLGREN Natural Resource Ecology Laboratory Colorado State University Fort Collins CO 80523-1499 USA Fort collins Science center U.S. Geological Survey 2150 Centre Ave. Building C Fort Collins CO 80526 USA

Habitat suitability models have been used to predict the present and future potential distribution of a variety of spe- cies. Eurasian tree sparrows Passer montanus, native to Eurasia, have established populations in other parts of the world. In North America, their current distribution is limited to a relatively small region around its original introduction to St. Louis, Missouri. We combined data from the Global Biodiversity Information Facility with current and future climate data to create habitat suitability models using Maxent for this species. Under projected climate change scenarios, our models show that the distribution and range of the Eurasian tree sparrow could increase as far as the Pacific Northwest and Newfoundland. This is potentially important in-formation for prioritizing the management and control of this non-native species [current Zoology 57 （5）： 648--654, 2011].

关键词： Eurasian tree sparrows Passer montanus Maxent climate change Distribution model

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Syntaxin-1蛋白的多重功能(英文)

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生物物理学报 2011年第10期27卷 821-827页

作者：孙坚原 thomas c Südhof 中国科学院生物物理研究所斯坦佛大学分子细胞生理学系和神经科学研究所

Syntaxin-1是特异性地分布在神经细胞突触前质膜上的蛋白。它早期被作为分子量为35 kD的synaptotagmin-1结合蛋白,但很快就被认识到是细胞质膜融合的关键蛋白。Syntaxin-1通过与SNAP25和Synaptobrevin/VAMP蛋白聚合,进而形成被认为是神... 详细信息

Syntaxin-1是特异性地分布在神经细胞突触前质膜上的蛋白。它早期被作为分子量为35 kD的synaptotagmin-1结合蛋白,但很快就被认识到是细胞质膜融合的关键蛋白。Syntaxin-1通过与SNAP25和Synaptobrevin/VAMP蛋白聚合,进而形成被认为是神经突触囊泡融合必要因子的SNARE核心复合体。作为一个多结构域的蛋白,syntaxin-1与多个突触蛋白相互作用,其作用远超出了仅作为SNARE核心复合体中一个蛋白质成员的作用。本文着重介绍了有关syntaxin-1与其它SNARE组份蛋白、munc18蛋白和钙离子通道的相互作用及其功能的最新研究进展。全面揭示syntaxin-1作为SNARE核心复合体成员的功能以及超越这一功能的作用,还有待于对其结构以及与其它突触蛋白相互作用特性的进一步深刻理解。

关键词： Syntaxin 1蛋白 Munc18-1蛋白钙离子通道囊泡融合囊泡促成熟 complexin蛋白 synaptotagmin蛋白

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