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排序方式: 共有870条查询结果,搜索用时 15 毫秒
861.
In this paper, we are interested in real-valued backward stochastic differential equations with jumps together with their applications to non-linear expectations. The notion of non-linear expectations has been studied only when the underlying filtration is given by a Brownian motion and in this work the filtration will be generated by both a Brownian motion and a Poisson random measure. We study at first backward stochastic differential equations driven by a Brownian motion and a Poisson random measure and then introduce the notions of f-expectations and of non-linear expectations in this set-up. 相似文献
862.
Manuela Zubitur Agurtzane Mugica Javier Areizaga Milagros Cortázar 《Colloid and polymer science》2010,288(7):809-818
Nanocomposites of poly(p-dioxanone) (PPDO) with unmodified and organically modified layered double hydroxide (LDH) have been
prepared by melt extrusion method. Dodecyl sulfate was used as organic modifier. The morphology of nanocomposites was analyzed
by X-ray diffraction and transmission electron microscopy and their thermal properties by differential scanning calorimetry
and thermogravimetric analysis. It has been found that the organic modifier decisively influences the nanocomposite morphology,
resulting in a higher level of exfoliation. In addition, the glass transition temperature of nanocomposites was slightly higher
than in case of unfilled PPDO. Moreover, the crystallization was delayed by LDH incorporation. The above behavior was ascribed
to interactions between carbonyl groups of polymer matrix and hydroxyl groups of LDH, as supported by Fourier transformed
infrared analysis. Interestingly, two different crystallization processes have been observed in the nanocomposite of PPDO
and organically modified LDH. Unmodified and organo-modified LDH, practically did not alter the final melting point of PPDO.
However, the thermal decomposition behavior was clearly influenced by the morphology exhibited by nanocomposites. 相似文献
863.
We prove that every subvariety of BL-algebras which is not finitely generated is not σ-canonical. We also prove π-canonicity for an infinite family of subvarieties of BL-algebras that are not finitely generated. To do so we study the behavior
of canonical extensions of ordered sums of posets. 相似文献
864.
Manuela Zonfrillo Federica Andreola Ewa K. Krasnowska Gianluca Sferrazza Pasquale Pierimarchi Annalucia Serafino 《Molecules (Basel, Switzerland)》2022,27(11)
Eucalyptus essential oil and its major constituent eucalyptol are extensively employed in the cosmetic, food, and pharmaceutical industries and their clinical use has recently expanded worldwide as an adjuvant in the treatment of infective and inflammatory diseases. We previously demonstrated that essential oil from Eucalyptus globulus (Labill.) (EO) stimulates in vitro the phagocytic activity of human monocyte-derived macrophages and counteracts the myelotoxicity induced by the chemotherapeutic 5-fluorouracil in immunocompetent rats. Here we characterize some mechanistic aspects underlying the immunostimulatory ability exerted by EO on macrophages. The internalization of fluorescent beads, fluorescent zymosan BioParticles, or apoptotic cancer cells was evaluated by confocal microscopy. Pro-inflammatory cytokine and chemokine release was determined by flow cytometry using the BD cytometric bead array. Receptor involvement in EO-stimulated phagocytosis was assessed using complement- or IgG-opsonized zymosan particles. The localization and expression of podosome components was analyzed by confocal microscopy and western blot. The main results demonstrated that: EO-induced activation of a macrophage is ascribable to its major component eucalyptol, as recently demonstrated for other cells of innate immunity; EO implements pathogen internalization and clearance by stimulating the complement receptor-mediated phagocytosis; EO stimulates podosome formation and increases the expression of podosome components. These results confirm that EO extract is a potent activator of innate cell-mediated immunity and thereby increase the scientific evidence supporting an additional property of this plant extract besides the known antiseptic and anti-inflammatory properties. 相似文献
865.
苹果品质检测的可见-近红外激光漫反射光谱图像法的方法研究 总被引:3,自引:0,他引:3
利用可见-近红外激光漫反射光谱图像法及化学计量学方法检测了苹果的可溶性固形物含量和硬度。为了消除苹果形状对品质检测的影响,分析了5个不同波长的激光(680,780,880,940和980 nm)照射在富士苹果果面形成的光斑图像,并通过一系列图像处理方法得出了的苹果形状修正算法。分别利用修正前后的光谱图像参数建立苹果可溶性固形物含量和硬度的偏最小二乘回归(PLSR)模型,模型预测值和真实值之间的相关系数从0.78和0.80分别提高到0.87和0.89。为了消除果面镜面反射对苹果内部品质检测的影响,文章提出了象素强度频率检测法,并比较了利用果面光斑图像中光强均值和不同强度对应的象素强度频率建立的苹果硬度和可溶性固形物含量的PLSR模型效果,得出象素强度频率的模型效果更好。苹果可溶性固形物含量和硬度PLSR模型中预测均方根误差(RMSEP)分别从1.28°Brix和8.23 N.cm-2降低到0.84°Brix和6.17 N.cm-2。 相似文献
866.
David Welch Norman J. Kleiman Peter C. Arden Christine L. Kuryla Manuela Buonanno Brian Ponnaiya Xuefeng Wu David J. Brenner 《Photochemistry and photobiology》2023,99(1):168-175
Far-UVC radiation, typically defined as 200–235 nm, has similar or greater anti-microbial efficacy compared with conventional 254-nm germicidal radiation. In addition, biophysical considerations of the interaction of far-UVC with tissue, as well as multiple short-term safety studies in animal models and humans, suggest that far-UVC exposure may be safe for skin and eye tissue. Nevertheless, the potential for skin cancer after chronic long-term exposure to far-UVC has not been studied. Here, we assessed far-UVC induced carcinogenic skin changes and other pathological dermal abnormalities in 96 SKH-1 hairless mice of both sexes that were exposed to average daily dorsal skin doses of 400, 130 or 55 mJ cm−2 of 222 nm far-UVC radiation for 66 weeks, 5 days per week, 8 h per day, as well as similarly-treated unexposed controls. No evidence for increased skin cancer, abnormal skin growths or incidental skin pathology findings was observed in the far-UVC-exposed mice. In addition, there were no significant changes in morbidity or mortality. The findings from this study support the long-term safety of long-term chronic exposure to far-UVC radiation, and therefore its potential suitability as a practical anti-microbial approach to reduce airborne viral and bacterial loads in occupied indoor settings. 相似文献
867.
Sebastiano Mantovani Angela Pintus Dr. Alessandro Kovtun Dr. Giulio Bertuzzi Dr. Manuela Melucci Prof. Marco Bandini 《European journal of organic chemistry》2023,26(37):e202300641
A new metal-free synthetic approach to functionalized indenes is documented. The use of commercially available graphene oxide (GO) allowed the direct access to indenyl cores (yield up to 80 %) via intramolecular Friedel-Crafts-type allylic alkylations with readily available Morita-Baylis-Hillman alcohols. Combined experimental and spectroscopic investigations contributed to shed light on the reaction mechanism dealing with a nanostructured carbon material-based C−C bond forming reaction. 相似文献
868.
Hermann Neitz Dr. Irene Bessi Valentin Kachler Manuela Michel Prof. Dr. Claudia Höbartner 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2023,135(1):e202214456
Arene-fluoroarene interactions offer outstanding possibilities for engineering of supramolecular systems, including nucleic acids. Here, we implement the tolane-perfluorotolane interaction as base pair replacement in DNA. Tolane (THH) and perfluorotolane (TFF) moieties were connected to acyclic backbone units, comprising glycol nucleic acid (GNA) or butyl nucleic acid (BuNA) building blocks, that were incorporated via phosphoramidite chemistry at opposite positions in a DNA duplex. Thermodynamic analyses by UV thermal melting revealed a compelling stabilization by THH/TFF heteropairs only when connected to the BuNA backbone, but not with the shorter GNA linker. Detailed NMR studies confirmed the preference of the BuNA backbone for enhanced polar π-stacking. This work defines how orthogonal supramolecular interactions can be tailored by small constitutional changes in the DNA backbone, and it inspires future studies of arene-fluoroarene-programmed assembly of DNA. 相似文献
869.
Non-isomorphic coupled cell networks with the same number of cells and with equivalent dynamics are said to be ODE-equivalent. Moreover, they are all related by a linear algebra condition involving their graph adjacency matrices. A network in an ODE-class is said to be minimal if it has a minimum number of edges among all the networks of the class. In this short paper we review the characterization of the minimal networks of an ODE-equivalence class and we present an example for the case of non-homogeneous networks. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
870.
Lisa Krapf Manuela Dezi Werner Reichstein Jürgen Köhler Silke Oellerich 《Colloids and surfaces. B, Biointerfaces》2011,82(1):25-32
We present a detailed AFM study on multilayered dry lipid films prepared from aqueous vesicle suspensions. Different preparation techniques were applied in order to optimize the preparation of homogeneous lipid films of various film thicknesses. Suspensions of preformed DOPC/DPPC vesicles were adsorbed onto indium tin oxide-coated glass coverslips, a substrate also commonly employed for the formation of giant liposomes. We found that the homogeneity of the lipid films could substantially be improved when applying a spin-coating step during the film preparation. These films were much more homogeneous than those prepared by conventional drop-casting and in addition the film thickness could be controlled. When using a combination of vesicle adsorption and spin-coating the quality and thickness of the films depended crucially on the lipid concentration of the vesicle suspension, the adsorption temperature and the adsorption time. For lipid films prepared by direct spin-coating the lipid concentration and the applied spin-coating sequence were critical parameters for the quality and thickness of the deposited lipid films. 相似文献