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61.
A 37‐year‐old hemodialysis patient appeared with unusual somnolence during 2 successive hemodialysis sessions. Blood gas analysis revealed hypercapnic respiratory failure and spirometry restrictive lung disease. After exclusion of other causes of restrictive lung disease with chest CT‐scan and cerebrum MRI, electrophysiological study revealed myopathy. Because besides lordosis and limb‐girdle gait the patient was ambulant the possibility of late‐onset Pompe's disease was set and confirmed with evaluation of α‐glucosidase activity and genetic analysis. Enzyme replacement therapy (ERT) with aglucosidase alfa was started. Due to inaccessibility of veins in the arm without the arteriovenous fistula, during the last 1 year, the patient received the ERT through the venous line of the hemodialysis circuit. Three years later the patient remains ambulant without the need of any assistant device and preserved his pulmonary function. This is the first described case of late‐onset Pompe's disease in a hemodialysis patient treated with ERT.  相似文献   
62.
Exact Knowledge Hiding through Database Extension   总被引:1,自引:0,他引:1  
In this paper, we propose a novel, exact border-based approach that provides an optimal solution for the hiding of sensitive frequent itemsets by (i) minimally extending the original database by a synthetically generated database part - the database extension, (ii) formulating the creation of the database extension as a constraint satisfaction problem, (iii) mapping the constraint satisfaction problem to an equivalent binary integer programming problem, (iv) exploiting underutilized synthetic transactions to proportionally increase the support of non-sensitive itemsets, (v) minimally relaxing the constraint satisfaction problem to provide an approximate solution close to the optimal one when an ideal solution does not exist, and (vi) by using a partitioning in the universe of the items to increase the efficiency of the proposed hiding algorithm. Extending the original database for sensitive itemset hiding is proved to provide optimal solutions to an extended set of hiding problems compared to previous approaches and to provide solutions of higher quality. Moreover, the application of binary integer programming enables the simultaneous hiding of the sensitive itemsets and thus allows for the identification of globally optimal solutions.  相似文献   
63.
Most of the text categorization algorithms in the literature represent documents as collections of words. An alternative which has not been sufficiently explored is the use of word meanings, also known as senses. In this paper, using several algorithms, we compare the categorization accuracy of classifiers based on words to that of classifiers based on senses. The document collection on which this comparison takes place is a subset of the annotated Brown Corpus semantic concordance. A series of experiments indicates that the use of senses does not result in any significant categorization improvement.  相似文献   
64.
The uniaxial compressive strength(UCS)of intact rock is one of the most important parameters required and determined for rock mechanics studies in engineering projects.The limitations and difficulty of conducting tests on rocks,specifically on thinly bedded,highly fractured,highly porous and weak rocks,as well as the fact that these tests are destructive,expensive and time-consuming,lead to development of soft computing-based techniques.Application of artificial neural networks(ANNs)for predicting UCS has become an attractive alternative for geotechnical engineering scientists.In this study,an ANN was designed with the aim of indirectly predicting UCS through the serpentinization percentage,and physical,dynamic and mechanical characteristics of serpentinites.For this purpose,data obtained in earlier experimental work from central Greece were used.The ANN-based results were compared with the experimental ones and those obtained from previous analysis.The proposed ANN-based formula was found to be very efficient in predicting UCS values and the samples could be classified with simple physical,dynamic and mechanical tests,thus the expensive,difficult,time-consuming and destructive mechanical tests could be avoided.  相似文献   
65.
A stand-alone power system that consists of a photovoltaic array and wind generators for the exploitation of renewable energy sources (RES), and that is capable of storing excessive energy in the form of hydrogen via water electrolysis for subsequent use in a polymer electrolyte membrane (PEM) fuel cell is currently being installed at Neo Olvio of Xanthi in Greece. The performance of two power management strategies (PMSs) that utilize a hysteresis band in the operation of the integrated system over a typical 4-month period is assessed. The state-of-charge (SOC) level of the accumulator is the main parameter that governs the operation of the electrolyzer and the fuel cell. The introduction of a hysteresis band in the boundary limits of the SOC of the accumulator provides larger flexibility in the operation of the electrolyzer, the fuel cell, and the accumulator. In this way, the units can be protected from heavy and unnecessary utilization or irregular operation (reduction of frequent start-ups and shut-downs). The simulated results for the implemented PMSs revealed important information about the reliability of the load satisfaction, the total operation time that each subsystem undergoes, as well as about the hydrogen inventory in the integrated system. The study also identified the effect of variation of hysteresis band size on the system performance as an important feature for the development of an integrated control strategy.  相似文献   
66.
67.
The IP Multimedia Subsystem (IMS) is defined by the 3rd Generation Partnership Project (3GPP) as a new core network domain. IMS provides a service control platform that allows creation of new multimedia and multi-session applications utilizing wireless and wireline transport capabilities. In this paper we will cover the concepts and standards defining IMS and review the network architecture from a mobile perspective. We will see how IMS interacts with the Packet Switched Domain (e.g. Wireless LAN, GPRS, and UMTS networks), the Internet, and application services. Then we will examine the key IMS capabilities and show how they can be combined to create new mobile IP services. Finally, we present a software architecture, which is enabled by IMS and allows development of unique applications (with multimedia/multi-session functionality, single/multi-user, service to user). The software architecture is illustrated by an example of a prototype application. This work was done when the author was with Siemens Communications Inc., Boca Raton, FL  相似文献   
68.
Ligustrum japonicum and Olea europaea leaf extracts prepared via domestic techniques were studied for antioxidant and aldose reductase inhibitory activity (ARI) in relation to individual phenol/flavonoid composition (HPLC‐various detection means) and content. On the same extract weight basis L. japonicum leaf extracts, poorer in total polar phenol (TPP) content and in most cases in flavonoids, were less efficient than olive leaf extracts in radical scavenging and in retarding lipid oxidation. On the same TPP content basis, the former were of comparable efficiency in radical scavenging but exhibited lower activity than the latter in bulk oils or liposomes. L. japonicum extracts were characterized by the presence of verbascoside and apigenin derivatives, whereas O. europaea extracts by that of oleuropein. Superiority of L. japonicum infusion versus O. europaea infusion was evidenced using the ARI activity assay either on the same extract weight or on TPP content basis. The former was also superior in comparison to oleuropein, tyrosol, and hydroxytyrosol activity. These findings suggest the presence of other active compounds besides the so far identified phenolics and enhance our view on the importance of Oleaceae plants as sources of bioactive compounds beyond O. europaea. Practical applications : Oleaceae plants are a unique source for the secoiridoid oleuropein or verbascoside that confer well documented biological properties. On continuation of our effort to valorize plants of this family as sources for functional constituents we examined, in parallel, leaf extracts of the less investigated species Ligustrum japonicum versus those of Olea europaea L. The data presented for the extracts obtained via domestic preparations techniques (infusions, decoctions, tinctures) are expected to attract the interest of those involved in herbal teas and dietary supplements sector.  相似文献   
69.
The efficient implementation of solar systems in buildings depends on the storage of energy yielded, as it can both increase the solar system's autonomy and make it a feasible solution for zero energy buildings, and make storage vessels more compact, reducing precious space requirements. This is of particular important in places with reduced time of sunshine, where solar systems are less effective, because of the deviation between solar radiation and the demand. The traditional storage options use water, which is practical, safe and low‐cost, especially when the storage requirements are small. However, when larger storage is needed, limits concerning the use of water exist, mainly due to the need for larger installation space and the increased thermal losses. The use of phase change materials (PCM) for thermal energy storage seems an upcoming technology. The main idea is the substitution of water with PCM, which feature larger specific energy storage capacity compared to other conventional materials. In the context of the specific paper, a combined solar thermal system used for the preparation of domestic hot water (DHW) and space heating (Solar Combi System) with two different types of storage is studied, for two Greek cities. The aim is to find out which is the most efficient way of storing energy with respect to the autonomy of the system, for a solar combi system. This is being achieved by determining the comparative autonomy of PCM and water storage system for various climates. It was proven that using PCM is advantageous, as it can extend the autonomy duration of the solar system for 2 to 8 hours, depending on the season and the climatic conditions. However, it was also seen that in solar combi systems used throughout the whole year, PCM are inefficient during summer period.  相似文献   
70.
Powdered β-glucan extracted from brewer's yeast (Yestimun, Leiber GmbH, Bramsche, Germany) was incorporated into skimmed-milk yogurt at varying concentrations (0.2–0.8% wt/wt) to investigate its potential application as a thickener. The effect of β-glucan fortification on the nutritional profile, microstructure, physicochemical properties, and texture of freshly prepared yogurts was investigated. Sensory evaluation was also conducted and was correlated with instrumental analysis. The addition of Yestimun significantly reduced the fermentation time of the yogurt mix from 4 h to 3 h. Scanning electron microscopy revealed that β-glucan particles formed small spherical clusters within the yogurt matrix. The majority of the physicochemical properties (syneresis, viscosity, color, and titratable acidity) remained unaffected by the incorporation of Yestimun in the recipe. Textural properties showed a gradual increment with increasing β-glucan concentration. Hardness, total work done, adhesive force, and adhesiveness increased by 19.27, 23.3, 21.53, and 20.76%, respectively, when using the highest amount of Yestimun powder. Sensory analysis (n = 40) indicated that fortifying yogurt with Yestimun at 0.8% (wt/wt) concentration may affect overall acceptance ratings, which was attributed to adverse flavor and aftertaste effects. However, the overall liking score of the yogurt (5.0/9.0) shows potential for commercialization of the product.  相似文献   
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