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31.

Table of Contents

Forthcoming Contributions  相似文献   
32.
The frequency of erythrocyturia in children with diagnosed food allergy was evaluated. The analysed clinical and immunological allergic process indicators and one year's observation confirm the allergic background of erythrocyturia in 2.6% of the examined group. There are indications for an elimination diet and the application of anti-allergic treatment in the above cases.  相似文献   
33.
The aging of the population is giving rise to a large number of studies aimed at improving the quality of life, considering diet as a major contributing factor in this life stage. The objectives of the present study were to evaluate the nutritional status of a group of institutionalized elderly in Murcia, Spain, and to relate the diet to anthropometric and biochemical indices, paying special attention to total antioxidant status. The dietary evaluation showed excessive intakes of proteins and lipids, and deficiencies in those of carbohydrates, dietary fiber, zinc, iodine and vitamins A, E and D. The high proportion of overweight observed were not significantly correlated to the energy intakes. Although total plasma antioxidant status was low (0.62 mM eq Trolox and 0.98 mM eq Fe(II)) compared with reference values, estimated oxidative risk in this group of elderly was low according to plasma levels of vitamins C, A & E.  相似文献   
34.
We describe a novel method for propagating disparity values using directional masks and a voting scheme. The driving force of the propagation direction is image gradient, making the process anisotropic, whilst ambiguities between propagated values are resolved using a voting scheme. This kind of anisotropic densification process achieves significant density enhancement at a very low error cost: in some cases erroneous disparities are voted out, resulting not only in a denser but also a more accurate final disparity map. Due to the simplicity of the method it is suitable for embedded implementation and can also be included as part of a system-on-chip (SOC). Therefore, it can be of great interest to the sector of the machine vision community that deals with embedded and/or real-time applications.  相似文献   
35.
In cloud systems, a clear necessity emerges related to the use of efficient and scalable computing resources. For this, accurate predictions on the load of computing resources are a key. Thanks to these accurate predictions, reduced power consumption and enhanced revenue of the system can be achieved, since resources can be ready when users need them and shutdown when they are no longer needed. This work presents an architecture to manage web applications based on cloud computing, which combines both local and public cloud resources. This work also presents the algorithms needed to efficiently manage such architecture. Among them, a load forecasting algorithm has been developed based on Exponential Smoothing. An use case of the e-learning services of our University presenting the behaviour of our architecture has been evaluated through a series of simulations. Among the most remarkable results, power consumption is reduced by 32 % at the cost of 367.31 US$ a month compared with the current architecture.  相似文献   
36.
In a study conducted in Sweden and the United States, subjects judged their own driving skills in relation to other drivers. The results showed that a majority of subjects regarded themselves as more skillful than the average driver. This result was compared with that obtained from similar studies on the population of Polish amateur and professional drivers. The outcomes of this comparison confirmed the existence of an optimistic tendency to overestimate one's own driving skill. This tendency was observed in various groups of drivers differing in cultural background. Finally, the influence of this tendency upon risk estimates of traffic accidents and inefficiency of safety propaganda are discussed.  相似文献   
37.
Superpipelined high-performance optical-flow computation architecture   总被引:1,自引:0,他引:1  
Optical-flow computation is a well-known technique and there are important fields in which the application of this visual modality commands high interest. Nevertheless, most real-world applications require real-time processing, an issue which has only recently been addressed. Most real-time systems described to date use basic models which limit their applicability to generic tasks, especially when fast motion is presented or when subpixel motion resolution is required. Therefore, instead of implementing a complex optical-flow approach, we describe here a very high-frame-rate optical-flow processing system. Recent advances in image sensor technology make it possible nowadays to use high-frame-rate sensors to properly sample fast motion (i.e. as a low-motion scene), which makes a gradient-based approach one of the best options in terms of accuracy and consumption of resources for any real-time implementation. Taking advantage of the regular data flow of this kind of algorithm, our approach implements a novel superpipelined, fully parallelized architecture for optical-flow processing. The system is fully working and is organized into more than 70 pipeline stages, which achieve a data throughput of one pixel per clock cycle. This computing scheme is well suited to FPGA technology and VLSI implementation. The developed customized DSP architecture is capable of processing up to 170 frames per second at a resolution of 800 × 600 pixels. We discuss the advantages of high-frame-rate processing and justify the optical-flow model chosen for the implementation. We analyze this architecture, measure the system resource requirements using FPGA devices and finally evaluate the system’s performance and compare it with other approaches described in the literature.  相似文献   
38.
We present the development and evaluation of a realtime indoor localisation system for tracking people. Our aim was to track a person’s indoor position using dead-reckoning, while limiting position error without depending on extensive wireless network infrastructure. The Indoor People Tracker used wearable motion sensors, a floor-plan map and a limited wireless sensor network for proximity ranging. We evaluated how the position accuracy of the Indoor People Tracker was affected by floor-plan map features, wireless proximity range and motion information. The advantage of the Indoor People Tracker was found; it was able to achieve accurate position resolution with minimal error, while not depending on wireless proximity.  相似文献   
39.
The great advances made over the last few years in the identification of signalling molecules that pattern the limb bud along the three axes make the limb an excellent model system with which to study developmental mechanisms in vertebrates. The understanding of the signalling networks and their mutual interactions during limb development requires the characterisation of the corresponding downstream genes. In this study we report the expression pattern of Slug, a zinc-finger-containing gene of the snail family, during the development of the limb, and its regulation by distinct axial signalling systems. Slug expression is highly dynamic, and at different stages of limb development can be correlated with the zone of polarizing activity, the progress zone and the interdigital areas. We show that the maintenance of its expression is dependent on signals from the apical ectodermal ridge and independent of Sonic Hedgehog. We also report that, in the interdigit, apoptotic cells lie outside of the domains of Slug expression. The correlation of Slug expression with areas of undifferentiated mesenchyme at stages of tissue differentiation is consistent with its role in early development, in maintaining the mesenchymal phenotype and repressing differentiation processes. We suggest that Slug is involved in the epithelial-mesenchymal interactions that lead to the maintenance of the progress zone.  相似文献   
40.
One of the most harmful groups of coastal pollutants is the organotin compounds (OTCs) which have severe effects on both aquatic organisms and mammals including humans. The immunotoxic effects of OTCs were studied in the cultivated clam Tapes philippinarum by determining the immunosuppressant role on in vitro yeast phagocytosis at low doses (0.01, 0.05, 0.1 microM). The phagocytic index was significantly reduced in an irreversible non-lethal manner depending on concentration and lipophilic affinity. The order of inhibition was TBT > or = DBT > MBT for butyltins and TPTC > TPTA > or = TPTH for triphenyltins.  相似文献   
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