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101.
The classification of the papillomaviral sequence into types is satisfactory for many purposes, but the resulting catalog does not accurately depict the extent of diversification of this family of viruses. Phylogenetic and mutational analyses reveal that some viral forms are much more ancient than other forms. Episodic evolutionary events and zoonotic transmission may have contributed to the overall pattern. Convergent evolution appears to be the best explanation for the scattered occurrence across the family tree of viruses with high oncogenic risk. We look for the determinants of this risk among the less conserved residues of the viral E6 and E7 transforming proteins. 相似文献
102.
We measure with a gated intensified CCD camera the cross-polarized backscattered light from a linearly polarized laser beam penetrating a cloud made of spherical particles. In accordance with previously published results we observe a clear azimuthal pattern in the recorded images. We show that the pattern is symmetrical, that it originates from second-order scattering, and that higher-order scattering causes blurring that increases with optical depth. We also find that the contrast in the symmetrical features can be related to measurement of the optical depth. Moreover, when the blurring contributions are identified and subtracted, the resulting pattern provides a pure second-order scattering measurement that can be used for retrieval of droplet size. 相似文献
103.
Glidle A Yasukawa T Hadyoon CS Anicet N Matsue T Nomura M Cooper JM 《Analytical chemistry》2003,75(11):2559-2570
We describe a method, based on X-ray photoelectron spectroscopy (XPS) measurements, to assess the extent of protein adsorption or binding on a variety of different muTAS and biosensor interfaces. Underpinning this method is the labeling of protein molecules with either iodine- or bromine-containing motifs by using protocols previously developed for radiotracer studies. Using this method, we have examined the adsorption and binding properties of a variety of modified electrodeposited polymer interfaces as well as other materials used in muTAS device fabrication. Using polymer interfaces modified with poly(propylene glycol) (PPG) chains, our results indicate that a chain of at least approximately 30 monomer units is required to inhibit nonspecific adsorption from concentrated protein solutions. The XPS methodology was also used to probe specific binding of avidins and enzyme conjugates thereof to biotinylated and mixed biotin/PPG-modified polymer interfaces. In one example, using competitive binding, it was established that the mode of binding of a peroxidase-streptavidin conjugate to a biotinylated modified polymer interface was primarily via the streptavidin moiety (as opposed to nonspecific binding via the enzyme conjugate). XPS evaluation of nonspecific and specific peroxidase-streptavidin immobilization on various functionalized polymers has guided the design and fabrication of functionalized interdigitated electrodes in a biosensing muTAS device. Subsequent characterization of this device using scanning electrochemical microscopy (SECM) corroborated the adsorption and binding previously inferred from XPS measurements on macroscale electrodes. 相似文献
104.
Ravet N Abouimrane A Armand M 《Nature materials》2003,2(11):702; author reply 702-702; author reply 703
105.
Marion MORENA Bernard CANAUD Nathalie TERRIER Ludovic CANAUD Jean‐Paul CRISTOL 《Hemodialysis international. International Symposium on Home Hemodialysis》2007,11(Z1):S32-S38
Patients undergoing maintenance hemodialysis (HD) have a high prevalence of protein‐energy malnutrition and inflammation. As these 2 conditions often occur concomitantly in HD patients, they have been referred to together as the ‘malnutrition‐inflammation complex syndrome’ (MICS) or ‘malnutrition‐inflammation atherosclerosis’ (MIA) syndrome to emphasize its important association with atherosclerotic cardiovascular disease. Oxidative stress, which results from an imbalance between oxidants and antioxidant defense mechanisms, is well established in HD subjects and could contribute to the poor clinical outcome of these patients. The aim of the present review is to discuss in more detail the common consequences of MICS and oxidative stress and their possible relationships with the long‐term complications of HD patients, leading to the conclusion that a complex syndrome similar to the MICS or MIA is the oxidative stress‐inflammation association, which may be called the “oxidative stress complex syndrome.” 相似文献
106.
Nathalie Perrier Bruno Agard Pierre Baptiste Jean-Marc Frayret André Langevin Robert Pellerin Diane Riopel Martin Trépanier 《Computers & Operations Research》2013
Emergency response operations in electric distribution systems involve a host of decision-making problems at the reliability and contingency planning levels. Those operations include fault diagnosis, fault location, fault isolation, restoration, and repair. As the first of a two-part survey, this paper reviews optimization models and solution methodologies for reliability planning problems with fault considerations related to electric distribution operations. Contingency planning problems of emergency distribution response are discussed in the second part. The present paper surveys research on determining a distribution substation single-fault capacity, reallocating excess load, configuring distribution systems, partitioning a geographical area into service territories, and locating material stores and depots. 相似文献
107.
108.
Yves Richard Nadège Martiny Mathieu Rouault Nathalie Philippon Yann Tracol Thierry Castel 《International journal of remote sensing》2013,34(21):6763-6782
In semi-arid African regions (annual rainfall between 200 and 600 mm), variability of vegetative activity is mainly due to the rainfall of the current rainy season. In most of South Africa, the rainy season occurs from October to March. On average, vegetative activity lags rainfall by 1 to 2 months. The interannual variability in early summer (December to September) normalized difference vegetation index (NDVI) depends primarily on precipitation at the beginning (October to November) of the rainy season. However, once this primary control is removed, the residual interannual variability in NDVI highlights a double memory effect: a 1-year effect, referred to as Mem1, and a 7- to 10-month effect, referred to as Mem2. This article aims at better describing the influence of soil and vegetation characteristics on these two memory effects. The data sets used in this study are as follows: (1) a 19-year NDVI time series from National Oceanic and Atmospheric Administration (NOAA) satellites, (2) rainfall records from a network of 1160 rain-gauge stations compiled by the Water Research Commission (WRC), (3) vegetation types from Global Land Cover (GLC) 2000 and (4) soil characteristics from the soil and terrain database for Southern Africa (SOTERSAF). Results indicate that among 20–30% of NDVI variance that is not explained by the concurrent rainfall, one-third is explained by the two memory effects. Mem1 is found to have maximum effect in the northwest of our study domain, near the Botswana boundary, in the South Kalahari. Associated conditions are open grasslands growing on Arenosols. Mem1 is less important in the southeast, particularly in open grassland with shrubs growing on Cambisols. Thus, Mem1 mainly depends on soil texture. Mem2 is more widespread and its influence is the greatest in the centre, the south and the east of our domain. It is related to rainfall from January to April, which controls, beyond the intervening dry season, the interannual variations of NDVI (December to September) at the beginning of the next rainy season. Through these new findings, this article emphasizes again the high potential of remote-sensing techniques to monitor and understand the dynamics of semi-arid environments. 相似文献
109.
E. Hernández‐Hernández M. G. Neira‐Velázquez J. Mendez‐Nonell L. F. Ramos‐deValle 《应用聚合物科学杂志》2009,112(6):3510-3518
Carbon nanofibers (CNFs) were coated with an ultrathin layer of poly(acrylic acid) (PAA) via plasma polymerization. The effect of the plasma reactor parameters on the extent of the CNF modification was studied. SEM micrographs showed that surface roughness increased with the plasma treatment. The thickness of the ultrathin PAA layer deposited on the CNF was determined by STEM to be ca. 8 nm. Untreated and treated CNF were melt‐mixed with polyamide 6 (PA6) in a Brabender mixing chamber to obtain PA6/CNF nanocomposites. The effect of the plasma treatment on the dispersion and compatibility was examined and found to improve markedly. Fractured tensile specimens showed that the CNF seemed to be completely embedded in the polymer matrix, indicating high compatibility between the PA6 and the PAA‐coated CNF. Tensile stress and tensile modulus of PA6 nanocomposites with treated CNF were found to increase by 30 and 48%, respectively, when compared with those with untreated CNF. However, the increase in tensile stress and modulus with respect to pure PA6 was 52 and 88%, respectively. Finally, XRD showed that the CNF induce the formation of the α (alpha)‐crystalline phase in PA6. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
110.
M. J. Cantero F. A. Grünbaum L. Moral L. Velázquez 《Quantum Information Processing》2012,11(5):1149-1192
We review the main aspects of a recent approach to quantum walks, the CGMV method. This method proceeds by reducing the unitary evolution to canonical form, given by the so-called CMV matrices, which act as a link to the theory of orthogonal polynomials on the unit circle. This connection allows one to obtain results for quantum walks which are hard to tackle with other methods. Behind the above connections lies the discovery of a new quantum dynamical interpretation for well known mathematical tools in complex analysis. Among the standard examples which will illustrate the CGMV method are the famous Hadamard and Grover models, but we will go further showing that CGMV can deal even with non-translation invariant quantum walks. CGMV is not only a useful technique to study quantum walks, but also a method to construct quantum walks à la carte. Following this idea, a few more examples illustrate the versatility of the method. In particular, a quantum walk based on a construction of a measure on the unit circle due to F. Riesz will point out possible non-standard behaviours in quantum walks. 相似文献