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171.
We report here the sequence of a 9.3 kb DNA segment of chromosome XI of Saccharomyces cerevisiae, located between the MAK11 locus and the centromere. This sequence contains four long open reading frames (ORFs), YKL160, YKL162, YKL164, YKL165 and part of another ORF, YKL166, covering altogether 90% of the entire sequence. One of these ORFs, YKL164, corresponds to CCE1. Translation products of two other ORFs, YKL160 and YKL165, exhibit homology with previously known S. cerevisiae proteins: the ribosomal protein L10, and the MYO2 gene product, respectively.  相似文献   
172.
Real Time Fitting of Hand-Sketched Pressure Brushstrokes   总被引:1,自引:0,他引:1  
A method is described for fitting the outline of hand-sketched pressure brushstrokes with Bézier curves. It combines the brush-trajectory model, in which a stroke is generated by dragging a brush along a given trajectory, with a fast curve fitting algorithm. The method has been implemented for a vector-based drawing program in which the user draws with a cordless pressure-sensitive stylus on a digitizing tablet. From the trajectory followed by the stylus, its associated pressure data, and a specified brush, a stroke of variable width is computed and displayed in real time. First, the digitized trajectory is fitted, thus removing noise. Then, from polygonal approximations of the fitted trajectory and the brush outline, a polygonal approximation of the stroke outline is computed. Working with polygonal approximations reduces computations to simple geometric operations and greatly simplifies the treatment of dynamic, pressure-controlled brushes. Last, the polygonal approximation of the stroke outline is fitted. The result is a closed piecewise Bézier curve approximating the brushstroke outline to within an arbitrary error tolerance. Several examples of hand-sketched drawings realized with this method are presented.  相似文献   
173.
A semi-conducting phosphovanadate glass was tested as a possible material for positive electrode in solid state batteries.O.c. voltage with alkali metal (3.6 V/Li and 3.4 V/Na) is higher than for crystallized vanadium oxides and chemical intercalation of sodium or lithium is obtained using halogenated salts dissolved in organic solvents.  相似文献   
174.
A histological and ultrastructural study was conducted to characterize changes in beef muscle structure after heating. Pieces of rectus abdominis muscle were heated at 100 °C over varying time frames from 15 min to 60 min and at 270 °C for 1 min; samples were then prepared for optical and transmission electron microscopy. After 15 min of heating, at 100 °C, a lateral shrinkage in fibre of 48% and an increase in gaps between the myofibrillar masses of 27% was noted. No more significant evolution was observed as heating duration escalated. The ultrastructure showed strong myofibril to sarcolemma detachments in which granular aggregates, coming in part from myofibrillar proteins, are stored. Neighbouring muscle fibres showed strong heterogeneity in morphological behaviour after thermal treatment, suggesting that differences in composition and structure of the cytoskeleton proteins in the different fibres can cause denaturation/shrinkage of the proteins at different times along the timescale of microstructural changes during heating. Short heating at high temperatures expanded the gaps between myofibrillar mass, but the overall changes in the ultrastructure were similar to those obtained when heating at 100 °C.  相似文献   
175.
Although cultivation of Arabica coffee trees at high elevation is known to favourably affect the final quality of the beverage, quantitative data describing the influence of climatic conditions on the chemical composition of the seed are still lacking. Similarly, post-harvest treatments of the beans are known to affect the generation of flavour, but the chemical transformations that occur during wet processing are poorly understood. To better characterise the effects of the environment, wet processing and their possible interactions, we quantified the changes in the main chemical components of the coffee seed (lipids, chlorogenic acids, sugars and caffeine) caused by wet processing, and analysed how these changes were affected by the variations induced by the environment before harvest. Using 16 experimental plots in Reunion Island displaying broad climatic variations, we showed that chlorogenic acids and fatty acids in the seed were controlled by the mean air temperature during seed development. By contrast, total lipid, total soluble sugar, total polysaccharide and total chlorogenic acid contents were not influenced by climate. Glucose content was positively affected by altitude, while sorbitol content after wet processing depended directly on the glucose content in fresh seeds.  相似文献   
176.
New and improved : The incorporation of a 6‐chlorotryptophan (6‐Cl‐Trp) into a β‐peptide (M)‐314 helix leads to a high‐affinity hDM2 inhibitor, as demonstrated by fluorescence fluctuation analysis at single molecule resolution. When conjugated to penetratin, the newly derived hDM2 binder specifically inhibits tumour cell growth in vitro.

  相似文献   

177.
We report on the gelation capability of polystyrene/poly(2-vinyl pyridine) amphiphilic heteroarm polyelectrolyte stars in acidic salt-free aqueous media. The star polymers associate through hydrophobic interactions, by retraction of the stretched arms under no interdigitation conditions, in the dilute regime forming colloidal soft nanoparticles comprising about 6 stars, At concentrations significantly higher than the hydrodynamic overlap concentration (c > 40c), the crowding of the colloidal nanoparticles drives a jamming transition, leading to a colloidal gel. The intermediate overlap regime (c < c < 40c) is characterized by a significant compaction of the polyelectrolyte entities prior interdigitation and jamming.  相似文献   
178.
Subtype‐selective ligands are of great interest to the scientific community, as they provide a tool for investigating the function of one receptor or transporter subtype when functioning in its native environment. Several 4‐substituted (S)‐glutamate (Glu) analogues were synthesized, and altogether this approach has provided important insight into the structure–activity relationships (SAR) for ionotropic and metabotropic glutamate receptors (iGluRs and mGluRs), as well as the excitatory amino acid transporters (EAATs). In this work, three 4,4‐disubstituted Glu analogues 1 – 3 , which are hybrid structures of important 4‐substituted Glu analogues 4 – 8 , were investigated at iGluRs and EAATs. Collectively, their pharmacological profiles add new and valuable information to the SAR for the iGluRs and EAAT1–3.  相似文献   
179.
Emir Hammami  Thierry Villemur 《电信纪事》2006,61(11-12):1369-1402
Application deployment in sessions composed of several users is now a hot topic. These users communicate together with heterogeneous terminals. Deployed applications on these nodes must fit to the execution environment and must be interoperable with applications already installed on the others nodes of the session. In this paper, we propose an architecture, which provides a user with missing applications according to the session requirements while respecting compatibility and interoperability constraints. This decentralized and distributed architecture is based on a context-aware deployment algorithm running on each node. After discovering applications scattered on a peer-to-peer network, the algorithm generates deployment configurations needed for any deployment node. Then, the algorithm performs the necessary downloads and instantiations. We present our context-aware deployment platform composed of generic modules. These modules includeApis to build deployment services according to this architecture.  相似文献   
180.
Although the current production of oxide nanoparticles may be modest, the wide range of proposed applications and forecasted growth in production has raised questions about the potential impact of these nanoparticles on the environment and human health. Iron oxide nanoparticles have been proposed for an increasing number of biomedical applications although in vitro toxicity depending on the particles coating has been evidenced. The aim of this study was to examine the potential in vitro cyto- and genotoxicity on human dermal fibroblasts of DMSA-coated maghemite nanoparticles (NmDMSA) as a function of well-defined physicochemical states. Well-stabilized NmDMSA produced weak cytotoxic and no genotoxic effects. This is attributed in part to the DMSA coating, which serves as a barrier for a direct contact between nano-oxide and fibroblasts, inhibiting a potential toxic effect.  相似文献   
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