4,768 research outputs found
Practical Evaluation of a Network Mobility Solution
IFIP International Workshop on Networked Applications, Colmenarejo, Madrid/Spain, 6â8 July, 2005As the demand of ubiquitous Internet access and the current trend of all-IP communications keep growing, the necessity of a protocol that provides mobility management increases. The IETF has specified protocols to provide mobility support to individual nodes and networks. The Network Mobility (NEMO) Basic Support protocol is designed for providing mobility at IP level to complete networks, allowing a Mobile Network to change its point of attachment to the Internet, while maintaining ongoing sessions of the nodes of the network. All the mobility management is done by the mobile router whilst the nodes of the network are not even aware of the mobility.
The main aim of this article is evaluating the performance of the NEMO Basic Support protocol by using our implementation. We also discuss the design of an implementation of the NEMO Basic Support protocol.Publicad
Analysis of the effect of mobile terminal speed on WLAN/3G vertical handovers
Proceedings of IEEE Global Telecommunications Conference, GLOBECOM '06, San Francisco, California, 27 november - 1 december, 2006.WLAN hot-spots are becoming widely spread. This, combined with the availability of new multi-mode terminals integrating heterogeneous technologies, opens new business opportunities for mobile operators. Scenarios in which 3G coverage is complemented by WLAN deployments are becoming available. Thus, true all-IP based networks are ready to offer a new variety
of services across heterogeneous access. However, to achieve this, some aspects still need to be analyzed. In particular, the effect of the terminal speed on the detection and selection process of the preferred access network is not yet well understood. In
fact, efficiency of vertical handovers depends on the appropriate configuration of mobile devices. In this paper we present a
simulation study of handover performance between 3G and WLAN access networks showing the impact of mobile usersâ speed. The mobile devices are based on the IEEE 802.21 cross
layer architecture and use WLAN signal level thresholds as handover criteria. A novel algorithm to dynamically adjust terminalsâ configuration is presented.Publicad
Clinical Application of Physical Therapy in Neurorehabilitation
The knowledge from basic neuroscience studies on mechanisms of motor recovery and the development of theoretical models of learning and recovery has favoured the development and implementation of neurophysiologically sounded rehabilitative interventions [...]
Fuel Cell as Range Extender in Battery Electric Vehicles for Supply Chain Fleets
The aim of this chapter is to present an outlook about implementation of a range extender system based on fuel cells for battery electric vehicles. Such a system is highly feasible to be implemented in electric vehicles, in particular those used by beverage industry in city centres. The tourism is another industry that uses electric vehicles, for instance in resorts, hotels, airports, zoos, etc. As well, public transportation is another sector involved with this vehicular technology. These sectors are all the time looking for high efficiency and low costs; however, they also need to extend the range of the vehicles to fulfill some logistics requirements in a route. This chapter presents a numerical example for illustrating an implementation of fuel cell range extender system. Advantages, disadvantages, and business opportunities in fuel cell technology are presented
Design and Experimental Evaluation of a Route Optimisation Solution for NEMO
An important requirement for Internet protocol (IP)
networks to achieve the aim of ubiquitous connectivity is network
mobility (NEMO). With NEMO support we can provide Internet
access from mobile platforms, such as public transportation vehicles,
to normal nodes that do not need to implement any special
mobility protocol. The NEMO basic support protocol has been
proposed in the IETF as a first solution to this problem, but this
solution has severe performance limitations. This paper presents
MIRON: Mobile IPv6 route optimization for NEMO, an approach
to the problem of NEMO support that overcomes the limitations
of the basic solution by combining two different modes of operation:
a Proxy-MR and an address delegation with built-in routing
mechanisms. This paper describes the design and rationale of the
solution, with an experimental validation and performance evaluation
based on an implementation.Publicad
Poly-l/dl-lactic acid films functionalized with collagen IV as carrier substrata for corneal epithelial stem cells
Limbal epithelial stem cells (LESCs) are responsible for the renewal of corneal epithelium. Cultivated limbal epithelial transplantation is the current treatment of choice for restoring the loss or dysfunction of LESCs. To perform this procedure, a substratum is necessary for in vitro culturing of limbal epithelial cells and their subsequent transplantation onto the ocular surface. In this work, we evaluated poly-L/DL-lactic acid 70:30 (PLA) films functionalized with type IV collagen (col IV) as potential in vitro carrier substrata for LESCs. We first demonstrated that PLA-col IV films were biocompatible and suitable for the proliferation of human corneal epithelial cells. Subsequently, limbal epithelial cell suspensions, isolated from human limbal rings, were cultivated using culture medium that did not contain animal components. The cells adhered significantly faster to PLA-col IV films than to tissue culture plastic (TCP). The mRNA expression levels for the LESC specific markers, K15, P63α and ABCG2 were similar or greater (significantly in the case of K15) in limbal epithelial cells cultured on PLA-col IV films than limbal epithelial cells cultured on TCP. The percentage of cells expressing the corneal (K3, K12) and the LESC (P63α, ABCG2) specific markers was similar for both substrata. These results suggest that the PLA-col IV films promoted LESC attachment and helped to maintain their undifferentiated stem cell phenotype. Consequently, these substrata offer an alternative for the transplantation of limbal cells onto the ocular surface.This work was supported by the Carlos III National Institute of Health, Spain (CIBER-BBN and Spanish Network on Cell Therapy, (TerCel RD12/0019/0036), MINECO/FEDER, EU), and the Castilla y León Regional Government, Spain (Regional Center for Regenerative Medicine and Cell Therapy, SAN673/VA/28/08 and SAN126/VA11/09)
Therapeutic Effect of Human Adipose Tissue-Derived Mesenchymal Stem Cells in Experimental Corneal Failure Due to Limbal Stem Cell Niche Damage
ProducciĂłn CientĂficaLimbal stem cells are responsible for the continuous renewal of the corneal epithelium. The destruction or dysfunction of these stem cells or their niche induces limbal stem cell deficiency (LSCD) leading to visual loss, chronic pain, and inflammation of the ocular surface. To restore the ocular surface in cases of bilateral LSCD, an extraocular source of stem cells is needed to avoid dependence on allogeneic limbal stem cells that are difficult to obtain, isolate, and culture. The aim of this work was to test the tolerance and the efficacy of human adipose tissue-derived mesenchymal stem cells (hAT-MSCs) to regenerate the ocular surface in two experimental models of LSCD that closely resemble the different severity grades of the human pathology. hAT-MSCs transplanted to the ocular surface of the partial and total LSCD models developed in rabbits were well tolerated, migrated to inflamed tissues, reduced inflammation, and restrained the evolution of corneal neovascularization and corneal opacity. The expression profile of the corneal epithelial cell markers CK3 and E-cadherin, and the limbal epithelial cell markers CK15 and p63 was lost in the LSCD models, but was partially recovered after hAT-MSC transplantation. For the first time, we demonstrated that hAT-MSCs improves corneal and limbal epithelial phenotypes in animal LSCD models. These results support the potential use of hAT-MSCs as a novel treatment of ocular surface failure due to LSCD. hAT-MSCs represent an available, non-immunogenic source of stem cells that may provide therapeutic benefits in addition to reduce health care expenses.This work was supported by Instituto de Salud Carlos III, CIBERâBBN, Spain (CB06/01/003 MINECO/FEDER, EU); Regional Center for Regenerative Medicine and Cell Therapy, Castilla y LeĂłn, Spain; Ministry of Science and Innovation, Spain (SAF2010â14900); Ministry of Economy and Competitiveness and European Regional Development Fund, Spain (SAF2015â63594âR MINECO/FEDER, EU
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