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61.
A Web-enabled survey was conducted to improve knowledge of home refrigeration practices of French consumers (n = 809), with an emphasis on hygiene, and this information was used to establish recommendations. The survey targeted a convenience sample of working people. Analysis of the survey responses revealed that efforts should be directed toward improvement of microbiological control measures. Only 37% of respondents made sure the temperature in their refrigerator was 4 degrees C or below. Only 37% of respondents reported that they systematically wrapped food. Sponges, known to be frequently highly contaminated, were used by 89% of the respondents to clean their refrigerator, which indicates the need to recommend disinfection of sponges before they are used for cleaning. Twenty-seven percent of respondents used sodium hypochlorite (bleach), but it was applied without previous cleaning (21% of the users) or in the commercial concentrated form (7% of the users). The permanent presence of water condensation on the shelves was noted by 2% of respondents, suggesting imperfect closure of the door, with a consequence of higher energy consumption and water available for microbial circulation and growth. Thus, an important recommendation is to check the door gaskets and to ensure the tight closure of the door. Seventy percent of the respondents declared that they never put warm or hot food in the refrigerator. However, many people, when orally questioned, acknowledged that they leave dishes at ambient temperature overnight before putting them in the refrigerator. It therefore is essential to recommend that perishable food not be left for more than 2 h at ambient temperature. 相似文献
62.
Eric Galin Eric Gurin Adrien Peytavie Guillaume Cordonnier Marie‐Paule Cani Bedrich Benes James Gain 《Computer Graphics Forum》2019,38(2):553-577
Terrains are a crucial component of three‐dimensional scenes and are present in many Computer Graphics applications. Terrain modeling methods focus on capturing landforms in all their intricate detail, including eroded valleys arising from the interplay of varied phenomena, dendritic mountain ranges, and complex river networks. Set against this visual complexity is the need for user control over terrain features, without which designers are unable to adequately express their artistic intent. This article provides an overview of current terrain modeling and authoring techniques, organized according to three categories: procedural modeling, physically‐based simulation of erosion and land formation processes, and example‐based methods driven by scanned terrain data. We compare and contrast these techniques according to several criteria, specifically: the variety of achievable landforms; realism from both a perceptual and geomorphological perspective; issues of scale in terms of terrain extent and sampling precision; the different interaction metaphors and attendant forms of user‐control, and computation and memory performance. We conclude with an in‐depth discussion of possible research directions and outstanding technical and scientific challenges. 相似文献
63.
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65.
We present a method to transfer the appearance of one or a few exemplar SVBRDFs to a target image representing similar materials. Our solution is extremely simple: we fine-tune a deep appearance-capture network on the provided exemplars, such that it learns to extract similar SVBRDF values from the target image. We introduce two novel material capture and design workflows that demonstrate the strength of this simple approach. Our first workflow allows to produce plausible SVBRDFs of large-scale objects from only a few pictures. Specifically, users only need take a single picture of a large surface and a few close-up flash pictures of some of its details. We use existing methods to extract SVBRDF parameters from the close-ups, and our method to transfer these parameters to the entire surface, enabling the lightweight capture of surfaces several meters wide such as murals, floors and furniture. In our second workflow, we provide a powerful way for users to create large SVBRDFs from internet pictures by transferring the appearance of existing, pre-designed SVBRDFs. By selecting different exemplars, users can control the materials assigned to the target image, greatly enhancing the creative possibilities offered by deep appearance capture. 相似文献
66.
Schneider E Keller M Brennauer A Hoefelschweiger BK Gross D Wolfbeis OS Bernhardt G Buschauer A 《Chembiochem : a European journal of chemical biology》2007,8(16):1981-1988
Cyanine-5-labelled neuropeptide Y (NPY) was demonstrated to be an ideal universal fluorescent ligand for the combined investigation of NPY Y(1), Y(2) and Y(5) receptors. With respect to improved stability, detection of receptor subtypes in cells and tissues, and prevention of receptor internalization, small nonpeptidic fluorescent antagonists should be superior. Here we present a set of four fluorescent nonpeptide NPY Y(1) receptor (Y(1)R) antagonists. The highest affinity was obtained by labelling an N(G)-(6-aminohexanoyl)argininamide derived from the Y(1)R antagonist BIBP 3226, with Py-1, a small pyrylium dye. The fluorescent pyridinium-type Y(1)R antagonist, compound 4 had K(i) values of 29 nM and 2.7 nM, which were determined by radioligand binding and flow cytometry under equilibrium conditions, respectively; 4 had a K(b) value of 0.6 nM (Ca(2+) assay). The large Stoke's shift (541 vs. 615 nm) in buffer (PBS, pH 7.4) in the presence of 1% BSA and the red emission (quantum yield 56%) are advantageous with respect to the signal-to-noise ratio. The new probe was successfully used in fluorescence-based binding experiments evaluated by flow cytometry and confocal microscopy; this demonstrates the potential of pyrylium dyes for the preparation of fluorescent ligands that are applicable for the study of G protein-coupled receptors on living cells. 相似文献
67.
Schobert R Bernhardt G Biersack B Bollwein S Fallahi M Grotemeier A Hammond GL 《ChemMedChem》2007,2(3):333-342
Esters of 6-aminomethylnicotinic acid with various steroidal alcohols were treated with K(2)PtCl(4) to give the N,N-chelated dichloroplatinum(II) complex conjugates 4. Their interaction with plasmid DNA was monitored by electrophoretic mobility measurements. Their affinities towards sex hormone binding globulin (SHBG) and towards the nuclear estrogen receptor ER(alpha) were assessed by competitive displacement radioassays. The inhibitory effect of 4 on breast tumour cells MCF-7 ER(+)/ER(-) and MDA-MB-231 was investigated in vitro. Conjugates with 3-O-linked estrogens 4 a,b or 17-O-linked androgens 4 g bound strongly to SHBG. The conjugate complex 4 b, featuring a 3-O-linked estradiol, also bound strongly and agonistically to the estrogen receptor. It also elicited distinct growth retardation of MCF-7 (ER(+)) cells, presumably by a mechanism different from that of cisplatin. 相似文献
68.
Zeolite A imidazolate frameworks 总被引:2,自引:0,他引:2
Faujasite (FAU) and zeolite A (LTA) are technologically important porous zeolites (aluminosilicates) because of their extensive use in petroleum cracking and water softening. Introducing organic units and transition metals into the backbone of these types of zeolite allows us to expand their pore structures, enhance their functionality and access new applications. The invention of metal-organic frameworks and zeolitic imidazolate frameworks (ZIFs) has provided materials based on simple zeolite structures where only one type of cage is present. However, so far, no metal-organic analogues based on FAU or LTA topologies exist owing to the difficulty imposed by the presence of two types of large cage (super- and beta-cages for FAU, alpha- and beta-cages for LTA). Here, we have identified a strategy to produce an LTA imidazolate framework in which both the link geometry and link-link interactions play a decisive structure-directing role. We describe the synthesis and crystal structures of three porous ZIFs that are expanded analogues of zeolite A; their cage walls are functionalized, and their metal ions can be changed without changing the underlying LTA topology. Hydrogen, methane, carbon dioxide and argon gas adsorption isotherms are reported and the selectivity of this material for carbon dioxide over methane is demonstrated. 相似文献
69.
In this paper we describe a method for analysing video sequences and for representing them as mosaics or panoramas. Previous work on video mosaicking essentially concentrated on static scenes. We generalize these approaches to the case of a rotating camera observing both static and moving objects where the static portions of the scene are not necessarily dominant, as it has been often hypothesized in the past. We start by describing a robust technique for accurately aligning a large number of video frames under unknown camera rotations and camera settings. The alignment technique combines a feature‐based method (initialization and refinement) with rough motion segmentation followed by a colour‐based direct method (final adjustment). This precise frame‐to‐frame alignment allows the dynamic building of a background representation as well as an efficient segmentation of each image such that moving regions of arbitrary shape and size are aligned with the static background. Thus a motion panorama visualizes both dynamic and static scene elements in a geometrically consistent way. Extensive experiments applied to archived videos of track‐and‐field events validate the approach. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
70.
Wen Cao Changqing Cao Liejin Guo Hui Jin Matthew Dargusch Debra Bernhardt Xiangdong Yao 《International Journal of Hydrogen Energy》2017,42(15):9448-9457
The potential of diosgenin solid waste (DSW) to be a proper feedstock for hydrogen production from supercritical water gasification was assessed through thermodynamic analysis and experimental study. The thermodynamic analysis of DSW gasification in SCW was performed by Aspen Plus software based on the principle of minimum Gibbs free energy. The effects of temperature (500–650 °C), flow ratio of feedstock slurry to preheated water on the gasification were studied. K2CO3 and black liquor were used to catalyze the gasification of DSW. The morphological structures of DSW and residue char were characterized by SEM. The results showed that DSW was almost completely gasified at 650 °C without catalyst and the carbon gasification efficiency reached up to 98.55%. K2CO3 could significantly promote the gasification reactivity of DSW at a lower temperature. H2 yield was remarkably improved by adding black liquor. The SEM analysis indicated that parts of the organic matters reacted to form gases and liquid products, and K2CO3 was found to migrate into the residue char during the reactions. 相似文献