Multimedia watermarking techniques

Multimedia watermarking technology has evolved very quickly during the last few years. A digital watermark is information that is imperceptibly and robustly embedded in the host data such that it cannot be removed. A watermark typically contains information about the origin, status, or recipient of the host data. In this tutorial paper, the requirements and applications for watermarking are reviewed. Applications include copyright protection, data monitoring, and data tracking. The basic concepts of watermarking systems are outlined and illustrated with proposed watermarking methods for images, video, audio, text documents, and other media. Robustness and security aspects are discussed in detail. Finally, a few remarks are made about the state of the art and possible future developments in watermarking technology     

SUCNR1 Is Expressed in Human Placenta and Mediates Angiogenesis: Significance in Gestational Diabetes

Placental hypervascularization has been reported in pregnancy-related pathologies such as gestational diabetes mellitus (GDM). Nevertheless, the underlying causes behind this abnormality are not well understood. In this study, we addressed the expression of SUCNR1 (cognate succinate receptor) in human placental endothelial cells and hypothesized that the succinate–SUCNR1 axis might play a role in the placental hypervascularization reported in GDM. We measured significantly higher succinate levels in placental tissue lysates from women with GDM relative to matched controls. In parallel, SUCNR1 protein expression was upregulated in GDM tissue lysates as well as in isolated diabetic fetoplacental arterial endothelial cells (FpECAds). A positive correlation of SUCNR1 and vascular endothelial growth factor (VEGF) protein levels in tissue lysates indicated a potential link between the succinate–SUCNR1 axis and placental angiogenesis. In our in vitro experiments, succinate prompted hallmarks of angiogenesis in human umbilical vein endothelial cells (HUVECs) such as proliferation, migration and spheroid sprouting. These results were further validated in fetoplacental arterial endothelial cells (FpECAs), where succinate induced endothelial tube formation. VEGF gene expression was increased in response to succinate in both HUVECs and FpECAs. Yet, knockdown of SUCNR1 in HUVECs led to suppression of VEGF gene expression and abrogated the migratory ability and wound healing in response to succinate. In conclusion, our data underline SUCNR1 as a promising metabolic target in human placenta and as a potential driver of enhanced placental angiogenesis in GDM.     

Confocal microscopy reveals Myzitiras and Vthela morphotypes as new signatures of malignancy progression

G3S1 cells are a new line derived from EM‐G3 breast cancer cells by chronic nutritional stress and treatments with 12‐O‐tetradecanoylphorbol‐13‐acetate. These cells are capable of growing in standard medium. G3S1 cells exhibited elevated invasiveness in Matrigel invasion chambers as compared with parental EM‐G3 cells. Elevated invasiveness of G3S1 cells was accompanied by higher incidence of myzitiras morphotype (sucker‐like) and newly observed vthela morphotype (leech‐like) both inducible in Hanks' Balanced Salt Solution test. Time‐lapse phase contrast microscopy showed a capacity of G3S1 cells to form lobopodial protrusions already 20 min after seeding on gelatin. These protrusions could make contact with the dish and possibly produce the vthela shape. The possible relationship of mysitiras and vthela morphotypes to an increase in malignant potential marked by enhanced invasiveness was thus indicated. SCANNING 31: 102–106, 2009. © 2009 Wiley Periodicals, Inc.     

ZF公司面向中国的高性能变速器

文章介绍了ZF公司为轮式装载机特别研发的WG系列高性能变速器,其产品系列可覆盖9-30吨级的车辆.ZF高性能的动力换档变速器具有简单和坚固的零部件设计、采用精确调整轴承、整体式壳体结构和优越的电控系统等优点.     

Liquid chromatography-atmospheric pressure electron capture dissociation mass spectrometry for the structural analysis of peptides and proteins

Atmospheric pressure electron capture dissociation (AP-ECD) is an emerging technique with the potential to be a more accessible alternative to conventional ECD/electron transfer dissociation (ETD) methods because it can be implemented using a stand-alone ion source device suitable for use with any existing or future electrospray ionization mass spectrometer. With AP-ECD, no modification of the main instrument is required, so it may easily be retrofitted to instruments not originally equipped with ECD/ETD capabilities. Here, we present our first purpose-built AP-ECD source and demonstrate its use in conjunction with capillary LC for the analysis of substance P, a tryptic digest of bovine serum albumin, and a phosphopeptide mixture. Quality ECD spectra were obtained for all the samples at the low femtomole level, proving that LC-AP-ECD-MS is suitable for the structural analysis of peptides and protein digests, in this case using an unmodified quadrupole time-of-flight mass spectrometer built ca. 2002.     

Low-Frequency Instabilities in the Operation of Metallic Multi-Microchannel Evaporators

Visualization by high-speed videography and infrared surface thermography was used to compare the spatial and temporal maldistribution of flow, manifesting itself in pulsation and hot spot formation, respectively, in water evaporators consisting of either a single metallic foil with an array of mechanically micromachined microchannels or of several such foils assembled into an electrically powered micro heat exchanger. In the single layer devices examined by high-speed videography, pulsation in the frequency range below 20 Hz was found to be dominated by the generation of large bubbles in the inlet plenum. A redesign of the inlet with microchannels instead of a large plenum eliminated the pulsation at sub-audio frequencies, at the expense of a significantly increased pressure drop across the device. Infrared thermography of an electrically powered micro heat exchanger operated as an evaporator showed the formation of metastable hot spots as the result of maldistribution among different microchannel array layers. The formation of these hot spots could be eliminated by operating the device under heater cartridge temperature control conditions instead of constant power conditions.     

Gas-phase electrophoretic molecular mobility analysis of size and stoichiometry of complexes of a common cold virus with antibody and soluble receptor molecules

Attachment of a nonaggregating monoclonal antibody and of a soluble recombinant receptor molecule to the icosahedral nonenveloped human rhinovirus serotype 2 was studied with a nanoelectrospray ionization gas-phase electrophoretic molecular mobility analyzer (nESI-GEMMA). The virus mass, as determined via nESI-GEMMA, was within instrument accuracy (+/-6%) close to the theoretical value (8 x 10(6) Da) calculated from the sum of all constituents of one virus particle (60 copies of each of the four viral capsid proteins, the RNA genome, and one copy of the RNA-linked protein VpG). The formation of virus-antibody complexes of different stoichiometries (up to a mass 12.5 x 10(6) Da corresponding to 30 attached antibodies) and virus-receptor complexes (up to a mass 8.8 x 10(6) Da corresponding to 12 attached receptor molecules) was monitored. Via the volume derived from the electrophoretic mobility diameter (EMD), the stoichiometry of the HRV complexes was calculated. The accuracy of the EMD was within +/-0.5 nm, which corresponds to an accuracy of +/-4 antibodies and +/-5 receptor molecules in the respective complexes. For the first time, we here demonstrate the use of nESI-GEMMA for the analysis of the size and stoichiometry of biomolecules in high-order complexes in real time under normal pressure conditions.     

Polarization of skylight in the O(2)A band: effects of aerosol properties

Motivated by several observations of the degree of linear polarization of skylight in the oxygen A (O(2)A) band that do not yet have a quantitative explanation, we analyze the influence of aerosol altitude, microphysics, and optical thickness on the degree of linear polarization of the zenith skylight in the spectral region of the O(2)A band, between 755 to 775 nm. It is shown that the degree of linear polarization inside the O(2)A band is particularly sensitive to aerosol altitude. The sensitivity is strongest for aerosols within the troposphere and depends also on their microphysical properties and optical thickness. The polarization of the O(2)A band can be larger than the polarization of the continuum, which typically occurs for strongly polarizing aerosols in an elevated layer, or smaller, which typically occurs for depolarizing aerosols or cirrus clouds in an elevated layer. We show that in the case of a single aerosol layer in the atmosphere a determination of the aerosol layer altitude may be obtained. Furthermore, we show limitations of the aerosol layer altitude determination in case of multiple aerosol layers. To perform these simulations we developed a fast method for multiple scattering radiative transfer calculations in gaseous absorption bands including polarization. The method is a combination of doubling-adding and k-binning methods. We present an error estimation of this method by comparing with accurate line-by-line radiative transfer simulations. For the Motivated by several observations of the degree of linear polarization of skylight in the oxygen A (O(2)A) band that do not yet have a quantitative explanation, we analyze the influence of aerosol altitude, microphysics, and optical thickness on the degree of linear polarization of the zenith skylight in the spectral region of the O(2)A band, between 755 to 775 nm. It is shown that the degree of linear polarization inside the O(2)A band is particularly sensitive to aerosol altitude. The sensitivity is strongest for aerosols within the troposphere and depends also on their microphysical properties and optical thickness. The polarization of the O(2)A band can be larger than the polarization of the continuum, which typically occurs for strongly polarizing aerosols in an elevated layer, or smaller, which typically occurs for depolarizing aerosols or cirrus clouds in an elevated layer. We show that in the case of a single aerosol layer in the atmosphere a determination of the aerosol layer altitude may be obtained. Furthermore, we show limitations of the aerosol layer altitude determination in case of multiple aerosol layers. To perform these simulations we developed a fast method for multiple scattering radiative transfer calculations in gaseous absorption bands including polarization. The method is a combination of doubling-adding and k-binning methods. We present an error estimation of this method by comparing with accurate line-by-line radiative transfer simulations. For the O(2)A band, the errors in the degree of linear polarization are less than 0.11% for transmitted light, and less than 0.31% for reflected light. band, the errors in the degree of linear polarization are less than 0.11% for transmitted light, and less than 0.31% for reflected light.     

一种基于厚膜工艺的高集成度FAIMS迁移管的研制

基于厚膜工艺,研制了一种集成有进样接口、气路接口、温控元件和离子源固定装置等外围功能模块的高集成度FAIMS迁移管,阐述了其结构特征和制作方法。为验证其性能,搭建了相应的FAIMS外围检测平台,以丙酮和甲苯为样品进行实验,得到了它们的FAIMS谱图,并与基于MEMS工艺的非集成FAIMS迁移管所测得的丙酮和甲苯的谱图比较,证明了高集成度迁移管在功耗、漏电流、气密性、灵敏度、分辨率和稳定性等方面的优异性能,说明高集成度迁移管适合作为小型化FAIMS独立检测系统的核心器件。     

ALD functionalized nanoporous gold: thermal stability, mechanical properties, and catalytic activity

Nanoporous metals have many technologically promising applications, but their tendency to coarsen limits their long-term stability and excludes high temperature applications. Here, we demonstrate that atomic layer deposition (ALD) can be used to stabilize and functionalize nanoporous metals. Specifically, we studied the effect of nanometer-thick alumina and titania ALD films on thermal stability, mechanical properties, and catalytic activity of nanoporous gold (np-Au). Our results demonstrate that even only 1 nm thick oxide films can stabilize the nanoscale morphology of np-Au up to 1,000°C, while simultaneously making the material stronger and stiffer. The catalytic activity of np-Au can be drastically increased by TiO(2) ALD coatings. Our results open the door to high-temperature sensor, actuator, and catalysis applications and functionalized electrodes for energy storage and harvesting applications.