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91.
As a result of the growing demand for accurate and reliable personal authentication, biometric recognition, a substitute for or complement to existing authentication technologies, has attracted considerable attention. It has recently been reported that, along with its variants, BioHashing, a new technique that combines biometric features and a tokenized (pseudo-) random number (TRN), has achieved perfect accuracy, having zero equal error rates (EER) for faces, fingerprints and palmprints. There are, however, anomalies in this approach. These are identified in this paper, in which we systematically analyze the details of the approach and conclude that the claim of having achieved a zero EER is based upon an impractical hidden assumption. We simulate the claimants’ experiments and find that it is not possible to achieve their reported performance without the hidden assumption and that, indeed, the results are worse than when using the biometric alone.  相似文献   
92.
93.
The corrosion behaviour of tin in stagnant mono-, di- and trichloroacetic acids solutions in the pH range 1–6 and at concentrations 4.0 to 5 × 10?4 M was investigated. The results indicate behaviour that is generally the same but there is some dependence on the acid concentration and the pH value. In 4.0 to 10?2 M solutions, the corrosion rate (W) increased with increasing acid concentration and decreasing pH value from 1 to 4 as follows: log W=a+b log C, where b=0.70, 0.42 and 0.35 for tri-, di- and mono-chloroacetic acids respectively. At high concentrations 4.0 to 10?2 M and in the pH range 1–6, the steady state corrosion potential shifted in the negative direction with increase of acid concentration accompanied by an increase in the corrosion rate, indicating that the corrosion process becomes anodically controlled by the complexing of Sn2+ ions with organic acid anions and that the order of aggressiveness is mono-<di-<trichloroacetic acids. In dilute solutions (10?2 to 5.10?4 M) in the pH range 1–6 the steady state potential shifted in the noble direction with increase of acid concentration (accompanied by a remarkable decrease in the corrosion rate). Corrosion inhibition in dilute solutions was attributed to film formation on the surface of tin which may result from the hydrolysis of tin species.  相似文献   
94.
Recent studies have implicated herpesvirus 8 and Epstein-Barr virus in the development of cutaneous malignancies in immunosuppressed patients. In order to examine the strength of this association, we examined 37 malignant, pre-malignant and benign cutaneous epithelial neoplasms removed from immunosuppressed organ recipients for the presence of human herpesvirus 8 and Epstein-Barr viral genome sequences using polymerase chain reaction (PCR) and in situ hybridization. We examined 2 actinic keratoses, 1 benign keratosis, 11 invasive squamous cell carcinomas, 17 squamous cell carcinomas in situ and 6 basal cell carcinomas. We also examined 4 basal cell carcinomas, 1 invasive squamous cell carcinoma and 3 squamous cell carcinomas in immunocompetent hosts. In contrast to findings reported by other investigators, we were unable to detect viral genome sequences in any of the biopsies examined. Our findings suggest that human herpesvirus 8 and Epstein-Barr virus likely do not play an etiologic role in cutaneous epithelial oncogenesis in immunocompromised patients.  相似文献   
95.
A technique for selecting a low-order system to approximate a high-order model has been suggested by Davison [2]. A critical component in this technique is the criterion used to select the most appropriate order and modes for the low-order approximation. Criteria have been discussed and analyzed by Mahapatra [5], [6], Rao, Lamba, and Rao [7], and Elrazaz and Sinha [3]. In this note we overcome deficiencies in the criteria that have been proposed and we introduce a new criterion which is rigorously justified. The criterion we suggest is also applicable when eigenvalues of the system are nonreal.  相似文献   
96.
97.
Fatty acids and essential oils from hydroponically cultivated Salvia officinalis leaves were analyzed by GC and GC–MS. Four different levels of NaCl (25, 50, 75 and 100 mM) were applied. The first results showed that salt treatment reduced significantly the plant growth by 61% and the total fatty acids (TFA) content by 32% at 100 mM NaCl. Alpha-linolenic, gadoleic, palmitic and oleic acids were the major fatty acids. Moreover, the polyunsaturated fatty acids decreased, while the monounsaturated ones increased with respect to increasing salinity. Regarding the essential oil composition, the main compounds were α-and β-thujone, 1,8-cineole, camphor, α-humulene, viridiflorol and manool at all salt treatments. The yield had a maximum increase at 75 mM NaCl. Hence, sage can be considered as moderately salt sensitive.  相似文献   
98.
The general objective of this work is to analyze energy input in a vacuum process with the incorporation of microwave heating. Thus, necessary criteria for designing an efficient freeze-drying operation are considered through the analysis of strategies based on the combination of different intensities of raxiiant and microwave heating.The other aim of this research topic is to study the kinetics of drying in relation to mass transfer parameters.Five freeze-drying strategies using both heating systems were used. Consequently, energy input could be related to diffusivity coefficients, temperature and pressure profiles during dehydration of the product and analyzed in comparison to a conventional freeze-drying process.  相似文献   
99.
100.
Laminopathies are a clinically heterogeneous group of disorders caused by mutations in the LMNA gene, which encodes the nuclear envelope proteins lamins A and C. The most frequent diseases associated with LMNA mutations are characterized by skeletal and cardiac involvement, and include autosomal dominant Emery–Dreifuss muscular dystrophy (EDMD), limb-girdle muscular dystrophy type 1B, and LMNA-related congenital muscular dystrophy (LMNA-CMD). Although the exact pathophysiological mechanisms responsible for LMNA-CMD are not yet understood, severe contracture and muscle atrophy suggest that mutations may impair skeletal muscle growth. Using human muscle stem cells (MuSCs) carrying LMNA-CMD mutations, we observe impaired myogenic fusion with disorganized cadherin/β catenin adhesion complexes. We show that skeletal muscle from Lmna-CMD mice is unable to hypertrophy in response to functional overload, due to defective fusion of activated MuSCs, defective protein synthesis and defective remodeling of the neuromuscular junction. Moreover, stretched myotubes and overloaded muscle fibers with LMNA-CMD mutations display aberrant mechanical regulation of the yes-associated protein (YAP). We also observe defects in MuSC activation and YAP signaling in muscle biopsies from LMNA-CMD patients. These phenotypes are not recapitulated in closely related but less severe EDMD models. In conclusion, combining studies in vitro, in vivo, and patient samples, we find that LMNA-CMD mutations interfere with mechanosignaling pathways in skeletal muscle, implicating A-type lamins in the regulation of skeletal muscle growth.  相似文献   
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