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121.
Silvia Casarotto Anna M Bianchi Sergio Cerutti Giuseppe A Chiarenza 《IEEE engineering in medicine and biology magazine》2005,24(1):68-77
The aim of this article is to compute reliable templates of event-related potentials (ERPs) for homogeneous groups of subjects and to automatically quantify the morphological characteristics of the ERPs. We developed a method based on dynamic time warping (DTW). The method was applied to ERPs recorded from normal and dyslexic children during two reading tasks. We found that characteristic latency and amplitude changes of ERP components are due to task and pathology. Our results support the idea that dyslexia involves different and complex cerebral functions aside from the language system. This mathematical approach provides reproducible analysis criteria that are crucial for the reliability of ERP analysis. 相似文献
122.
Borgonovo F. Zorzi M. Fratta L. Trecordi V. Bianchi G. 《Selected Areas in Communications, IEEE Journal on》1996,14(4):609-622
This paper presents a new architecture for the third-generation mobile systems, capture-division packetized access (CDPA), that overcomes most of the limitations of present cellular systems. It addresses the three main issues of radio access, namely the channel reuse, the multiple access, and the handover problems, in complete adherence to packet-switching principles. The CDPA channel reuse mechanism is a completely new alternative with respect to time-division, frequency-division, or code-division multiple-access (TDMA, FDMA, and CDMA, respectively), which achieve communication parallelism by subdividing the bandwidth a priori among cells. In CDPA, a single frequency channel is used and parallel transmissions are achieved through the “capture” capability of receivers. The hybrid reservation-polling multiple access mechanism used in CDPA is able to integrate any kind of traffic and guarantees almost immediate retransmission of packets that are not captured, thus assuring their correct reception. Finally, the packet-switching approach allows connectionless communications with any base station (BS), and eliminates the need for extra radio traffic in managing handovers. This turns out to be very effective in local area systems where the required high bandwidth is obtained by using a pico-cell structure. We present the CDPA architecture, discuss some implementation issues, and evaluate its performance under a variety of system parameters and operating conditions, using analytical and simulation methods 相似文献
123.
In this article we refer to the market of vehicular networks, where groups of customers located in the same public vehicle (e.g., a train or bus) connect to a terrestrial network through a wireless/satellite backbone link. Elastic buffering is a proxy management technique devised to decouple the multimedia information retrieval rate on the network backbone from the playout streaming rate at the user terminal. It has been shown in the past that the application of elastic buffering mechanisms in terrestrial networks brings significant advantages in terms of network effectiveness. We show that elastic buffering is an extremely effective means to reduce, or even eliminate, streaming service outage due to intermittent backbone connectivity, such as that occurring when a vehicle moves through tunnels. Moreover, we show that elastic buffering is not only a technique suitable for multimedia information retrieval services, but can be effectively applied to delayed real-time services. 相似文献
124.
M Zhang T Caragine H Wang PS Cohen G Botchkina K Soda M Bianchi P Ulrich A Cerami B Sherry KJ Tracey 《Canadian Metallurgical Quarterly》1997,185(10):1759-1768
125.
G Bianchi V Terrinoni G Carbone W Anselmi N Bellini M Rengo 《Canadian Metallurgical Quarterly》1997,18(6-7):378-381
The Authors point out how AEFs represent a serious complication of aortic vascular surgery. Special attention is given to the diagnostic and therapeutic approach, also supported by a wide review of the literature. 相似文献
126.
C Bianchi P Brambilla D Cella F Ragogna C Tettamanti M Del Puppo MG Kienle G Chiumello G Ruotolo 《Canadian Metallurgical Quarterly》1997,131(6):928-931
We evaluated endogenous cholesterol synthesis and plasma lipid profile longitudinally from birth to 1 year old in infants who were exclusively breast-fed (n = 19) or formula-fed (n = 19) for the first 4 months of life. At 1 and 4 months of age, breast-fed infants had higher plasma total and low-density lipoprotein cholesterol and apolipoprotein B levels than formula-fed infants, whereas plasma mevalonate and lanosterol levels were not different between the two study groups. 相似文献
127.
The spleen is the most commonly injured organ in blunt abdominal trauma. There remains much controversy in the diagnosis and management of the injured spleen, with a recent trend toward nonoperative management. A 5-year period was reviewed at a rural, Level I trauma center to address issues of operative versus nonoperative management. During this time period, there were 136 patients identified as having trauma to the spleen. Most (95%) were the result of blunt trauma, and a majority of these were from motor vehicle accidents. Computed tomography was the most frequent method of diagnosis. Approximately half of the patients underwent immediate operative intervention. Of those initially observed, 10 patients (16%) eventually were operated on. Most of the cases were due to underestimation of the severity of the splenic injury, and most received blood transfusion. This experience suggests that observation for splenic trauma is appropriate in many cases, as long as the surgeon is certain the spleen is not actively bleeding and the patient will not require blood transfusion. 相似文献
128.
129.
U Grohmann ML Belladonna R Bianchi C Orabona E Ayroldi MC Fioretti P Puccetti 《Canadian Metallurgical Quarterly》1998,9(3):315-323
The aim of this in vitro study was to investigate whether the phenomenon of advanced bone formation in grooves (Bone 18, 115, 1995) is restricted to calcified biological materials. Osteoblasts were released from neonatal rat calvaria by enzyme digestion and cultured in EMEM and 10% FCS. At confluence, they were seeded on to dentine, bone, plastic, titanium, or silicon, which had been grooved using a water-cooled, diamond-edged, slow-speed or high-speed circular saw or reciprocating wire saw, or a rotating dental burr. Cultures were continued for 14-21 days, with a few extended for up to 7 weeks. Osteoblasts were also cultured on grooved dentine and plastic with or without added Stanozolol for 18 days, and bone formation assayed by measuring the total length of bone formed in the grooves in each specimen. Bone formation always occurred first within the grooves and was appositional. It formed on both calcified biological and nonbiological substrates, but developed consistently earlier on the biological substrates, and conformed to both the main grooves and the secondary finer grooving within them. Surface features at scales ranging from the millimeter to nanometer therefore influence the development of bone in vitro and possibly in vivo. The described site-induced bone formation system is valuable as an in vitro assay for biomaterial and pharmaceutical research. 相似文献
130.
E Alleva F Cirulli M Bianchi GP Bondiolotti F Chiarotti L De Acetis AE Panerai 《Canadian Metallurgical Quarterly》1998,10(12):3664-3672
Interleukin-6 (IL-6) is a cytokine released by activated immune cells which has been shown to affect brain function. In this experiment aggressive and affiliative behaviour exhibited during agonistic encounters by transgenic male mice either not expressing (IL-6 -/-) or overexpressing (NSE-hIL-6) IL-6 in the central nervous system was investigated. All subjects were isolated for 24 days before the aggressive encounter and were 52 days old at the time of testing. Subjects were placed for 5 consecutive days in a neutral cage for 15 min with an opponent of the Balb/c strain that had been previously isolated for the same amount of time. The first and the last test sessions were videotaped to evaluate the first approach and the establishment of the social role, respectively. A number of behavioural categories were later scored. When compared with wild-type controls, IL-6 -/- mice showed a higher degree of aggressive behaviour as indicated by a higher frequency of Offensive Upright Posture, an effect more pronounced on the fifth encounter. On the contrary, NSE-hIL-6 subjects showed a tendency to be more involved in affiliative-type social interactions, displaying a higher frequency and duration of behaviours such as Anogenital, Nose or Body Sniff. IL-6 -/- mice showed a clear tendency to exhibit less affiliative interactions compared with their controls while dopamine levels were found to be modified in a number of brain regions in these mice. Overall, these data suggest that IL-6 affects both aggressive and affiliative-type interactions, although the behaviour of the NSE-hIL-6 subjects was less affected than that of the IL-6 -/- group. The effects of the genetic background of the animal in screening the outcome of gene manipulations on behaviour are also discussed. 相似文献