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61.
Palmoplantar keratodermas (PPKs) are characterized by thickness of stratum corneum and epidermal hyperkeratosis localized in palms and soles. PPKs can be epidermolytic (EPPK) or non epidermolytic (NEPPK). Specific mutations of keratin 16 (K16) and keratin 1 (K1) have been associated to EPPK, and NEPPK. Cases of mosaicism in PPKs due to somatic keratin mutations have also been described in scientific literature. We evaluated a patient presenting hyperkeratosis localized monolaterally in the right palmar area, characterized by linear yellowish hyperkeratotic lesions following the Blaschko lines. No other relatives of the patient showed any dermatological disease. Light and confocal histological analysis confirmed the presence of epidermolityic hyperkeratosis. Genetic analysis performed demonstrates the heterozygous deletion NM_006121.4:r.274_472del for a total of 198 nucleotides, in KRT1 cDNA obtained by a palmar lesional skin biopsy, corresponding to the protein mutation NP_006112.3:p.Gly71_Gly137del. DNA extracted from peripheral blood lymphocytes did not display the presence of the mutation. These results suggest a somatic mutation causing an alteration in K1 N-terminal variable domain (V1). The deleted sequence involves the ISIS subdomain, containing a lysine residue already described as fundamental for epidermal transglutaminases in the crosslinking of IF cytoskeleton. Moreover, a computational analysis of the wild-type and V1-mutated K1/K10 keratin dimers, suggests an unusual interaction between these keratin filaments. The mutation taster in silico analysis also returned a high probability for a deleterious mutation. These data demonstrate once again the importance of the head domain (V1) of K1 in the formation of a functional keratinocyte cytoskeleton. Moreover, this is a further demonstration of the presence of somatic mutations arising in later stages of the embryogenesis, generating a mosaic phenotype.  相似文献   
62.
In this transaction brief we consider the design of dual basis inversion circuits for GF(2m). Two architectures are presented-one bit-serial and one bit-parallel-both of which are based on Fermat's theorem. Finite field inverters based on Fermat's theorem have previously been presented which operate over the normal basis and the polynomial basis. However there are two advantages to be gained by forcing inversion circuits to operate over the dual basis. First, these inversion circuits can be utilized in circuits using hardware efficient dual basis multipliers without any extra basis converters. And second, the inversion circuits themselves can take advantage of dual basis multipliers, thus reducing their own hardware levels. As both these approaches require squaring in a finite field to take place, a theorem is presented which allows circuits to be easily designed to carry out squaring over the dual basis  相似文献   
63.
In this work, the sorption isotherms of xanthan powder obtained under static and dynamic conditions and their fitting with mathematical models were discussed. The transitions within xanthan-water systems have been investigated using a standard material characterization technique - Differential Scanning Calorimetry (DSC) - and two novel techniques - Dynamic Mechanical Thermal Analysis (DMTA) material pocket and Phase Transition Analysis (PTA). It was found that within water-xanthan systems, the onset temperature for the melting of freezable water obtained from DSC method was in agreement with freezable water melting peaks obtained via DMTA material pocket at levels of hydration when the freezable water was present. Also, low-temperature transitions, related to polysaccharide-water interactions, were observed by both techniques within xanthan systems which contained no freezable water. However, the use of the PTA technique was limited to xanthan systems with low water content.  相似文献   
64.
Subcutaneous (sc) administration of capsaicin (50 mg/kg) at Postnatal Days 2 and 5 exerted long-term effects on isolation-induced aggressive behavior of adult mice of the CD-1 strain. Isolated capsaicin-treated mice (scored during a 10-min session) showed the highest frequency and the longest duration of total attacks, attacks, rattling, and offensive upright posture when compared with nonisolated capsaicin-treated Ss and both isolated and nonisolated vehicle control animals. Hypothalamic substance P (SP) was assessed by radioimmunoassay. Capsaicin treatment significantly lowered hypothalamic SP content in both isolated and nonisolated mice. Moreover, individual scores of isolated capsaicin-treated Ss showed a significant correlation between SP depletion and expression of offensive upright posture. Isolation per se was revealed to play an important role in depleting SP from the hypothalamus. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
65.
66.
In this paper error detection is applied to four finite field bit-serial multipliers. It is shown that by using parity prediction, on-line error detection can be incorporated into these multipliers with very low hardware overheads. These hardware overheads are generally independent of m and comprise only a handful of gates, so for large values of m these overheads are particularly low. The fault coverage of the presented structures has been investigated by simulation experiment and shown to range between 90% and 94.3%.  相似文献   
67.
Organic fluorescent molecules are infiltrated in the channels of zeolite L nanocrystals, thus creating organic–inorganic fluorescent nanoparticles. Combined with dielectric matrices, these fluorescent nanopigments open the way to the realization of novel optical devices. In this paper, the optical measurement of the quantum yield of fluorescent zeolites by means of a precise and reliable diffuse reflectance technique is presented. Several possible factors that may affect the fluorescence quantum yield are also investigated.  相似文献   
68.
Renewable and low carbon fuel standards being developed at federal and state levels require an estimation of the life cycle carbon intensity (LCCI) of candidate fuels that can substitute for gasoline, such as second generation bioethanol. Estimating the LCCI of such fuels with a high degree of confidence requires the use of probabilistic methods to account for known sources of uncertainty. We construct life cycle models for the bioconversion of agricultural residue (corn stover) and energy crops (switchgrass) and explicitly examine uncertainty using Monte Carlo simulation. Using statistical methods to identify significant model variables from public data sets and Aspen Plus chemical process models,we estimate stochastic life cycle greenhouse gas (GHG) emissions for the two feedstocks combined with two promising fuel conversion technologies. The approach can be generalized to other biofuel systems. Our results show potentially high and uncertain GHG emissions for switchgrass-ethanol due to uncertain CO? flux from land use change and N?O flux from N fertilizer. However, corn stover-ethanol,with its low-in-magnitude, tight-in-spread LCCI distribution, shows considerable promise for reducing life cycle GHG emissions relative to gasoline and corn-ethanol. Coproducts are important for reducing the LCCI of all ethanol fuels we examine.  相似文献   
69.
Sheared velocity profiles pervade all wind‐turbine applications, thus making it important to understand their effect on the wake. In this study, a single wind turbine is modeled using the actuator‐line method in the incompressible Navier–Stokes equations. The tip vortices are perturbed harmonically, and the growth rate of the response is evaluated under uniform inflow and a linear velocity profile. Whereas previous investigations of this kind were conducted in the rotating frame of reference, this study evaluates the excitation response in the fixed frame of reference, thus necessitating a frequency transformation. It is shown that increasing the shear decreases the spatial growth rate in the upper half of the wake while increasing it in the lower half. When scaled with the local tip vortex parameters, the growth rate along the entire azimuth collapses to a single value for the investigated wavenumbers. We conclude that even though the tip‐vortex breakdown is asymmetric in sheared flow, the scaled growth rates follow the behavior of axisymmetric helical vortices. An excitation amplitude reduction by an order of magnitude extends the linear growth region of the wake by one radius for uniform inflow. In the sheared setup, the linear growth region is extended further in the top half than in the bottom half because of the progressive distortion of the helical tip vortices. An existing model to determine the stable wake length was shown to be in close agreement with the observed numerical results when adjusted for shear.  相似文献   
70.
The aim of this work was the analysis of the experimental results of a transparent alumina (BMA15) ceramic which was fabricated by Spark Plasma Sintering (SPS) from nanopowder (BMA15, Baikowski Chimie, France), at different temperatures (1200°C, 1250°C, 1300°C). With the application of a maximum uniaxial pressure of 73 MPa during all the fabrication-cycle (more than 3 hours). We sought an optimal sintering temperature combining better optical and mechanical properties of our pellets. The sintered alumina (BMA15) has a crystalline and dense microstructure. The samples sintered at 1200°C exhibit the best optical properties, in particular: good real inline transmission (RIT) and an optical gap greater than those of the samples sintered at 1250°C and 1300°C. Due to their low density, the Young modulus of alumina sintered at 1200 °C, deduced by ultrasound, has a low value which is about 385 GPa. Similarly, its small grain size gives it a better Vickers hardness ~ 21 GPa. Therefore, the value of the coefficient of friction μ stabilizes around the mean value of 0.21.  相似文献   
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