Ubiquitous Internet in an integrated satellite-terrestrial environment: The SUITED solution

yesThe current Internet architecture appears to not be particularly suited to addressing the emerging needs of new classes of users who wish to gain access to multimedia services made available by ISPs, regardless of their location, while in motion and with a guaranteed level of quality. One of the main objectives of so-called nextgeneration systems is to overcome the limitations of today¿s available Internet by adopting an approach based on the integration of different mobile and fixed networks. The SUITED project moves in this direction since it aims at contributing to the design and deployment of the global mobile broadband system (GMBS), a unique satellite/terrestrial infrastructure ensuring nomadic users access to Internet services with a negotiated QoS. A description of the main features of the GMBS architecture, characterized by the integration of a multisegment access network with a federated ISP network is given in this article. The GMBS multimode terminal is schematically described, and an overview of the so-called QoS-aware mobility management scheme, devised for such a heterogeneous scenario,is provided

Performance Analysis of Satellite Payload Architectures for Mobile Services

YesThis paper is concerned with the effects on the network performance of moving parts of what is considered traditionally to belong to the ground segment to on board the satellite. Initially, an overview of geostationary satellite communication systems and payload technology is presented, followed by a description of the network architecture and protocols that are the basis of the simulation models. The results obtained from this testbed are presented before concluding with a discussion of the results obtained

Multi-model attribution of upper-ocean temperature changes using an isothermal approach

1

Fractionation of potent antioxidative components from langsat (Lansium domesticum) peel

Lansium domesticum (langsat) is a popular tropical fruit bearing trees across the Southeast Asia region. It is cultivated mainly for its fruit, while the peel of langsat as wastes of fruit consumption has been traditionally used as medicine. The aim of this study was to evaluate the total phenolic content (TPC) and antioxidant activity of different fractions of ethanolic extract of langsat peel. The extract was fractionated using open column chromatography and the antioxidant components were observed based on high-performance thin layer chromatography (HPTLC). TPC of the extract and extract fractions (FI˗FIII) was estimated using Folin-Ciocalteu reagent assay, while their antioxidant activity was evaluated using DPPH radical scavenging assay. Highest TPC was estimated in the ethanolic extract of langsat peel compared to its extract fractions. No significant difference was found for TPC among the extract fractions. The extract also had the highest DPPH radical scavenging activity, followed by FIII and FII, but no radical scavenging activity was observed in FI. The result obtained from HPTLC also showed that no band of antioxidative compounds was observed under UV or white light. Based on the antioxidative components found in the peel extract of langsat, the fruit peel is a potential source of antioxidants for development of nutraceutical. Fractionation of the extract is not an ideal technique for producing nutraceutical

Upregulation and function of GADD45γ in unilateral ureteral obstruction

We performed differential display analysis to determine transcriptional activity in the rat kidney, following unilateral ureteral obstruction and found a 12-fold increase in the expression of Growth Arrest and DNA Damage-45γ (GADD45γ), a stress-responsive molecule that interacts with cell-cycle proteins. GADD45γ was strongly expressed in as little as 6 h following ureteric obstruction in the renal tubules, and was also found in kidney tissue of patients with chronic glomerulonephritis. Adenovirus-mediated expression of GADD45γ in cultured renal tubular cells activated p38 along with a significant upregulation of C–C and C–X3–C chemokine ligands and fibrosis-related factors such as several matrix metalloproteinases, transforming growth factor-β1, decorin, and bone morphogenetic protein 2. Silencing of GADD45γ expression significantly blunted the upregulation of these inflammatory and fibrogenic mediators and monocyte infiltration in the ureteral obstructed rat kidney. Our study shows that GADD45γ is quickly upregulated in the kidney with an obstructed ureter, enhancing the production of factors regulating the pathogenesis of kidney disease

Pulmonary artery wave intensity analysis in pulmonary hypertension associated with heart failure and reduced left ventricular ejection fraction

Wave intensity analysis (WIA) uses simultaneous changes in pressure and flow velocity to determine wave energy, type, and timing of traveling waves in the circulation. In this study, we characterized wave propagation in the pulmonary artery in patients with pulmonary hypertension associated with left‐sided heart disease (PHLHD) and the effects of dobutamine. During right heart catheterization, pressure and velocity data were acquired using a dual‐tipped pressure and Doppler flow sensor wire (Combowire; Phillips Volcano), and processed offline using customized Matlab software (MathWorks). Patients with low cardiac output underwent dobutamine challenge. Twenty patients with PHLHD (all heart failure with reduced left ventricular ejection fraction) were studied. Right ventricular systole produced a forward compression wave (FCW), followed by a forward decompression wave (FDW) during diastole. Wave reflection manifesting as backward compression wave (BCW) following the FCW was observed in 14 patients. Compared to patients without BCW, patients with BCW had higher mean pulmonary artery pressure (28.7 ± 6.12 vs. 38.6 ± 6.5 mmHg, p = 0.005), and lower pulmonary arterial capacitance (PAC: 2.88 ± 1.75 vs. 1.73 ± 1.16, p = 0.002). Pulmonary vascular resistance was comparable. Mean pulmonary artery pressure of 34.5 mmHg (area under the curve [AUC]: 0.881) and PAC of 2.29 mL/mmHg (AUC: 0.833) predicted BCW. The magnitude of the FCW increased with dobutamine (n = 11) and correlated with pulmonary artery wedge pressure. Wave reflection in PHLHD is more likely at higher pulmonary artery pressures and lower PAC and the magnitude of reflected waves correlated with pulmonary artery wedge pressure. Dobutamine increased FCW but did not affect wave reflection

Correlation between the bath composition and nanoporosity of DC-electrodeposited Ni-Fe alloy

The outstanding mechanical strength of as-deposited DC-electrodeposited nanocrystalline (nc) Ni-Fe alloys has been the subject of numerous researches in view of their scientific and practical interest. However, recent studies have reported a dramatic drop in ductility upon annealing above 350°C, associated with a concomitant abnormal rapid grain growth. The inherent cause has been ascribed to the presence of a detrimental product or by product in the bath, which affects either the microstructure or causes defects in the concentration and/or distribution of the as-deposited films. The present work has been inspired by the observed abnormal behaviour of annealed electrodeposited nc Ni-Fe alloy, which has here been addressed by considering the relationship between the composition of the bath (iron-chloride, nickel-sulphate solution, saccharin and ascorbic acid) and deposition defects (e.g. grain boundary pores) in the case of an nc Ni-Fe (Fe 48 wt%) alloy. The current investigations have included X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) in both as-deposited and post-annealed conditions (300°C–400°C). XPS depth profiling with Ar ion sputtering showed a significant amount of C and O impurities entrapped in the foils during deposition. As such impurities are often overlooked in common analytical techniques, new scenarios may need to be rationalised to explain the observed drop in tensile ductility of the as-deposited Ni-Fe alloys

SatNEx: A Network of Excellence Providing Training in Satellite Communications

YesSatellite communications represents a specialised area of telecommunications. While the development of satellite technology is relatively slow in comparison to wireless networks evolution, due to the need for high reliability, the services that satellites are able to offer are evolving at much the same pace as their terrestrial counterparts. It is within this context that the satellite communications network of excellence (SatNEx) has evolved its initiative, the aim being to serve the engineering community with the latest technological trends, while also providing a solid grounding in the fundamentals for those new to the subject area.European Commission Framework Programme