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Intestinal Kaposi's sarcoma may mimic gastrointestinal stromal tumor in HIV infection

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World journal of Gastroenterology 2007年第33期13卷 4514-4516页

作者： A Zoufaly s schmiedel AW Lohse j van Lunzen Department of Medicine 1 University Medical Center Hamburg-Eppendorf Hamburg Germany Infectious Diseases Unit University Medical Center Hamburg-Eppendorf Hamburg Germany

Diffuse intestinal Kaposi＇s sarcoma shares macroscopic and histopathologic features with gastrointestinal stromal tumors. Correct diagnosis may pose a clinical challenge. We describe the case of a young HIV-1-infected African lady without advanced immunodeficiency, who presented with a diffuse spindle cell tumor of the gut. Initial diagnosis was of a gastrointestinal stromal tumor, based on endoscopy and histopathology. further evaluation revealed evidence for human herpesvirus 8 （HHV8） and the diagnosis had to be changed to diffuse intestinal Kaposi＇s sarcoma. Antiretroviral triple therapy together with chemotherapy was commenced, and has led to the rapid remission of intestinal lesions. With a background of HIV infection, the presence of HHV8 as the causative agent of Kaposi＇s sarcoma should be determined, as distinct treatment is indicated.

关键词： Gastrointestinal stromal tumor Kaposi's sarcoma HIV infection Human herpesvirus 8 c-kit

Enhanced acetone sensing performance of nanostructured sm2O3 doped snO2 thick films

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journal of Rare Earths 2017年第8期35卷 813-823页

作者： f.I.shaikh L.P.Chikhale j.Y.Patil I.s.Mulla s.s.suryavanshi school of Physical sciences Solapur University Solapur 413255 (M.S.) lndia Council of scientific and Industrial Research Pashan Pune 411008 India

In the present work, we synthesized sm2O3 doped snO2 in order to prepare a selective acetone sensor with fast response, quick recovery and good repeatability. Pure as well as 2 mol.%, 4 mol.%, 6 mol.% and 8 mol.% sm2O3 doped snO2 nanostructured samples were synthesized by using a co-precipitation method. The characterization of the samples was done by thermogravimetric and differential thermo-gravimetric analysis（TG-DTA）, X-ray diffraction（XRD）, field emission gun-scanning electron microscopy（fEG-sEM）, energy dispersive analysis by X-rays（EDAX）, high resolution scanning electron microscopy（HR-TEM）, selected area X-ray diffraction（sAED）, Brunauer-Emmet-Teller（BET） and ultraviolet-visible-near infrared（UV-Vis-NIR） spectroscopy techniques. The gas response studies of liquid petroleum gas, ammonia, ethanol and acetone vapor were carried out. The results showed that sm doping systematically lowered operating temperature and enhanced the gas response and selectivity for acetone. The response and recovery time for 6 mol.% sm2O3 doped snO2 thick film at the operating temperature of 250 °C were 15 and 24 s, respectively.

关键词： tin oxide samarium oxide screen printing thick film acetone sensor rare earths

Comparing children＇s Homo sapiens and chimpanzees＇ Pan troglodytes quantity judgments of sequentially presented sets of items

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Current Zoology 2011年第4期57卷 419-420,421-428页

作者： Michael j. BERAN julie s. jOHNsON-PYNN Christopher READY Language Research Center Georgia State University Atlanta GA 30302 USA Department of Psychology Berry College Mount Berry GA 30149 USA

We presented a quantity judgment task that involved comparing two sequentially presented sets of items to preschoolers and chimpanzees using nearly identical procedures that excluded verbal instructions to children. Trial difficulty in this task reflected the ratio difference between sets of discrete items where larger ratios （e.g., 0.80 as from comparing 4 to 5） were more difficult than smaller ones （e.g., 0.50 as from comparing 4 to 8）. Children also completed verbal-based tasks probing the relationskip between counting proficiency and performance on the quantity judgment task of sequentially presented identical sized items. Both species＇ performance was best when ratios between comparison sets were small regardless of set size in all types of tasks. Generally, chimpanzees and older children performed better than younger children except at larger ratios. Children＇s counting proficiency was not related to success in choosing the larger of two quantities of identical-sized items. These results indicate that chimpanzees and children share an approximate number sense that is reflected through analog magnitude estimation when comparing quantities [Current Zoology 57 （4）： 419-428, 2011].

关键词： Numerical cognition Quantity judgments Children Chimpanzees Pan troglodytes

Contribution to the understanding of the performance differences between commercial current collectors in Li–s batteries

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journal of Energy Chemistry 2021年第11期30卷 295-306,I0007页

作者： A.Benitez f.Luna-Lama ACaballero E.Rodriguez-Castellon j.Morales Dpto.Química Inorgánica e Ingeniería Química Instituto Universitario de Nanoquímica(IUNAN)Universidad de Córdoba14071 CórdobaSpain Dpto.de Química Inorgánica Cristalografía y MineralogíaFacultad de CienciasUniversidad de Málaga29071 MálagaSpain

Lithium–sulfur batteries have been recognised as highly promising next-generation batteries, due to their low cost and high theoretical energy density. Despite numerous advances in this technology over the last decade, its commercialisation is still a challenge that has not yet been achieved. Many efforts have been made to improve the problems that these batteries present, mainly by investigating different cathode manufacturing strategies, testing novel Li anodes, new additives in the electrolytes, and modified separators or interlayers. However, the characteristics of the current collectors used in the preparation of the electrodes have been rarely addressed. Three commercial collectors are commonly used in basic research on Li–s batteries: Al foil, carbon coated Al foil (Al-C), and carbon paper (gas diffusion layer, GDL). In this work, a detailed study of the electrochemical response of these commercial collectors has been carried out. The tests were carried out on two s composites formed by carbons of a different natures, commercial carbon black and synthetic N-doped graphene. In addition, the s impregnation method was different, using either melt diffusion at 155 ℃ or ethylenediamine as s solvent, respectively. In both systems, the results were similar – the electrodes supported on GDL delivered higher specific capacities than those supported on Al and Al-C, with minimal differences between the two. Of the different collector properties examined to explain this behaviour, namely Al corrosion, electrical conductivities, surface-level composition, and surface texture, only the latter had a significant effect in the performance of GDL-based electrodes. sEM images revealed a rough and cracked surface formed by the agglomerated carbon particles that give rise to a complex pore system, predominantly consisting of macropores. All of these features are beneficial for a better anchoring of the active material on the collector surface, in addition to enhancing the wettabi

关键词： Current collector Carbon paper Aluminum foil Lithium–sulfur battery

Highly efficient passive Tesla valves for microfluidic applications

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Microsystems & Nanoengineering 2022年第5期8卷 125-136页

作者： sebastian Bohm Hai Binh Phi Ayaka Moriyama erich Runge steffen strehle jörg König Christian Cierpka Lars Dittrich Theoretical Physics I Technische Universität IlmenauWeimarer Straße 2598693 IlmenauGermany Research and Development 5microns GmbHMargarethenstraße 698693 IlmenauGermany Institute of Micro-and Nanotechnologies Gustav-Kirchhoff-Straße 798693 IlmenauGermany Microsystems Engineering Technische Universität IlmenauMax-Planck-Ring 1298693 IlmenauGermany Physics and Astronomy Carleton CollegeOne North CollegeNorthfield 55057 MinnesotaUSA Engineering Thermodynamics Technische Universität IlmenauAm Helmholtzring 198693 IlmenauGermany

A multistage optimization method is developed yielding Tesla valves that are efficient even at low flow rates,characteristic,e.g.,for almost all microfluidic systems,where passive valves have intrinsic advantages over active *** report on optimized structures that show a diodicity of up to 1.8 already at flow rates of 20μl s^(−1) corresponding to a Reynolds number of *** of the design is a topological optimization based on the finite element *** is set-up to yield easy-to-fabricate valve structures with a small footprint that can be directly used in microfluidic *** numerical two-dimensional optimization takes into account the finite height of the channel approximately by means of a so-called shallow-channel *** on the threedimensionally extruded optimized designs,various test structures were fabricated using standard,widely available microsystem manufacturing *** manufacturing process is described in detail since it can be used for the production of similar cost-effective microfluidic *** the experimentally fabricated chips,the efficiency of the different valve designs,i.e.,the diodicity defined as the ratio of the measured pressure drops in backward and forward flow directions,respectively,is measured and compared to theoretical predictions obtained from full 3D calculations of the Tesla *** agreement is *** addition to the direct measurement of the diodicities,the flow profiles in the fabricated test structures are determined using a two-dimensional microscopic particle image velocimetry(μPIV)***,a reasonable good agreement of the measured flow profiles with simulated predictions is observed.

关键词： backward Highly optimization

One kind motion of controllable constrained Birkhoffian system:the absence of constraints

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Acta Mechanica sinica 2020年第3期36卷 735-741页

作者： j.Chen f.X.Mei s.X.Liu Y.X.Guo school of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China school of Physics Liaoning UniversityShenyang 110000China

This paper is devoted to discuss the motion of controllable constrained Birkhoffian system along with its absence of *** first step is to establish the autonomous and non-autonomous differential equations of motion of the system,based on Pfaff-Birkhoff ***,the existence of constraint multipliers are exhaustively ***,the definition of one kind motion of the system,called free motion,is given,which is described and analyzed by the absence of constraints that are determined by constraint *** 2 illustrates that one system can realize its free motion by selecting proper control *** particular,theorem 2 provides that one system can naturally realize free motion when we consider the integral of the unconstrained Birkhoffian system as the constraints of constrained Birkhoffian ***,the results obtained are illustrated by several examples.

关键词： Constrained Birkhoffian system Kinematic control Absence of constraint free motion

CONTINUOUs sTIffNEss MODE NANOINDENTATION REsPONsE Of POLY(METHYL METHACRYLATE) sURfACEs

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Chinese journal of Polymer science 2013年第8期31卷 1096-1107页

作者： T. Iqbal B.j. Briscoe s. Yasin P.f. Luckham Chemical Engineering Department University of Engineering & Technology Chemical Engineering Department Imperial College

Indentation is a comparatively simple and virtually nondestructive method of determining mechanical properties of material surfaces by means of an indenter inducing a localized deformation. The paper present experimental results of the load-displacement curves, the hardness and the elastic modulus data, and associated analysis for poly（methyl methacrylate）（PMMA） surfaces as a function of contact displacement. The experimental results include continuous stiffness indentations performed using constant loading rate and constant displacement rate experiments. The continuous stiffness indentation involves continuous calculation of a material stiffness, and hence hardness and elastic modulus of surfaces, during discrete loading-unloading cycles, as in a conventional indentation routine, and in a comparatively smaller time constant, The dependence of the compliance curves, the hardness, the elastic modulus and the plasticity index upon the imposed penetration depth, the applied normal load and the deformation rate are described. Tip area and load frame calibrations for the continuous stiffness indentation are also reported. The paper includes practical considerations encountered during indentation of polymers specifically at low penetration depths. The experimental results show a peculiarly harder response of PMMA surfaces at the submicron （near to surface） layers.

关键词： Nanoindentation PMMA Hardness Modulus Continuous stiffness.

Long-Term Effect of Organic and Mineral fertilization on soil Physical Properties Under Greenhouse and Outdoor Management Practices

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Pedosphere 2011年第4期21卷 443-453页

作者： j.f.HERENCIA P.A.GARCíA-GALAVís C.MAQUEDA Instituto de Investigación y formación Agraria y Pesquera "Las Torres-Tomejil" sevilla (IfAPA) Carretera Sevilla-Cazalla de la Sierrra km 12.241200 Alcalá del RíoSeville (Spain) Instituto de Recursos Naturales y Agrobiología (CsIC) Apdo.1052.41080-Sevilla (Spain)

To evaluate the use of organic amendments as an alternative to conventional fertilization,a 10-year experiment on a loam soil was conducted under a crop rotation system in both greenhouse and outdoor plots applied with chemical fertilizers (NPK) and vegetal compost (organic fertilizer) in the Guadalquivir River Valley,*** effect of these two different fertilization regimes on the soil physical properties was *** organic carbon (OC),soil bulk density (BD),soil water retention (WR),available water content (AWC),aggregate stability (As),and soil physical quality (Dexter's index,s) were *** use of organic fertilizer increased OC and resulted in a significant increase in As and a decrease in BD compared to the mineral fertilizer application in both greenhouse and outdoor *** outdoor plots showed the lowest BD values whereas the greenhouse plots showed the highest As *** the last years of the 10-year experiment the s parameter was significantly higher in organic fertilizer plots,especially for greenhouse *** the end of the study period,there were no significant differences in WR at field capacity (fC) between treatments in both systems;the AWC was also similar in the greenhouse plots but higher in the mineral outdoor *** mineral fertilizer treatments,a small improvement in the physical properties was also observed due to the utilization of less aggressive tillage compared with the previous intensive cropping *** soil properties were correlated with soil *** sustainable management techniques such as the use of organic amendments and low or no tillage improved soil physical properties,despite the differences in management that logically significantly affected the results.

关键词： aggregate stability bulk density organic matter vegetal compost water retention

MEDIUM-RANGE ORDER CLUsTERs IN fe-2.0%C ALLOY MELT

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Acta Metallurgica sinica(English Letters) 2003年第6期16卷 513-518页

作者： X.B.Qin s.j.Cheng X.f.Bian KeyLaboratoryofLiquidstructureandHeredityofMaterials MinistryofEducationShandongUniversityJi‘nan250061China MechanicalEngineeringDepartment ShandongUniversityofTechnologyZibo255000China

The structure of fe-2.0%C alloy melt was investigated at 1580, 1560, 1540 and 1450℃ by using an X-ray diffractometer respectively. The results showed that with decreasing temperature, the average atoms of cluster, the coordination numbers, the correlation radius and the atom density increased, whereas the pre-peak of the structure factors curve remained almost at the same position. The appearance of the pre-peak indicated that the liquid structure and the solid structure of the fe-2.0%C alloy were correlated.

关键词： liquid structure X-ray diffraction micro-inhomogeneous model,pre-peak structure factor