3G network traffic sources measurement and analysis

In this paper, we show statistical analyses of several types of traffic sources in a 3G network, namely voice, video and data sources. For each traffic source type, measurements were collected in order to, on the one hand, gain better understanding of the statistical characteristics of the sources and, on the other hand, enable forecasting traffic behaviour in the network. The latter can be used to estimate service times and quality of service parameters. The probability density function, mean, variance, mean square deviation, skewness and kurtosis of the interarrival times are estimated by Wolfram Mathematica and Crystal Ball statistical tools. Based on evaluation of packet interarrival times, we show how the gamma distribution can be used in network simulations and in evaluation of available capacity in opportunistic systems. As a result, from our analyses, shape and scale parameters of gamma distribution are generated. Data can be applied also in dynamic network configuration in order to avoid potential network congestions or overflows. Copyright © 2013 John Wiley & Sons, Ltd.

A feasibility study for the provision of electronic healthcare tools and services in areas of Greece, Cyprus and Italy

Background Through this paper, we present the initial steps for the creation of an integrated platform for the provision of a series of eHealth tools and services to both citizens and travelers in isolated areas of thesoutheast Mediterranean, and on board ships travelling across it. The platform was created through an INTERREG IIIB ARCHIMED project called INTERMED. Methods The support of primary healthcare, home care and the continuous education of physicians are the three major issues that the proposed platform is trying to facilitate. The proposed system is based on state-of-the-art telemedicine systems and is able to provide the following healthcare services: i) Telecollaboration and teleconsultation services between remotely located healthcare providers, ii) telemedicine services in emergencies, iii) home telecare services for "at risk" citizens such as the elderly and patients with chronic diseases, and iv) eLearning services for the continuous training through seminars of both healthcare personnel (physicians, nurses etc) and persons supporting "at risk" citizens. These systems support data transmission over simple phone lines, internet connections, integrated services digital network/digital subscriber lines, satellite links, mobile networks (GPRS/3G), and wireless local area networks. The data corresponds, among others, to voice, vital biosignals, still medical images, video, and data used by eLearning applications. The proposed platform comprises several systems, each supporting different services. These were integrated using a common data storage and exchange scheme in order to achieve system interoperability in terms of software, language and national characteristics. Results The platform has been installed and evaluated in different rural and urban sites in Greece, Cyprus and Italy. The evaluation was mainly related to technical issues and user satisfaction. The selected sites are, among others, rural health centers, ambulances, homes of "at-risk" citizens, and a ferry. Conclusions The results proved the functionality and utilization of the platform in various rural places in Greece, Cyprus and Italy. However, further actions are needed to enable the local healthcare systems and the different population groups to be familiarized with, and use in their everyday lives, mature technological solutions for the provision of healthcare services.

Scheduler-dependent inter-cell interference and its impact on LTE uplink performance at flow level

The Long Term Evolution (LTE) cellular technology is expected to extend the capacity and improve the performance of current 3G cellular networks. Among the key mechanisms in LTE responsible for traffic management is the packet scheduler, which handles the allocation of resources to active flows in both the frequency and time dimension. This paper investigates for various scheduling scheme how they affect the inter-cell interference characteristics and how the interference in turn affects the user’s performance. A special focus in the analysis is on the impact of flow-level dynamics resulting from the random user behaviour. For this we use a hybrid analytical/simulation approach which enables fast evaluation of flow-level performance measures. Most interestingly, our findings show that the scheduling policy significantly affects the inter-cell interference pattern but that the scheduler specific pattern has little impact on the flow-level performance.

LTE uplink scheduling - flow level analysis

Long Term Evolution (LTE) is a cellular technology foreseen to extend the capacity and improve the performance of current 3G cellular networks. A key mechanism in the LTE traffic handling is the packet scheduler, which is in charge of allocating resources to active flows in both the frequency and time dimension. In this paper we present a performance comparison of three distinct scheduling schemes for LTE uplink with main focus on the impact of flow-level dynamics resulting from the random user behaviour. We apply a combined analytical/simulation approach which enables fast evaluation of flow-level performance measures. The results show that by considering flow-level dynamics we are able to observe performance trends that would otherwise stay hidden if only packet-level analysis is performed.

[Glomerulonephritis and vasculitis as causes of arterial hypertension]

The various types of glomerulonephritis, including many forms of vasculitis, are responsible for about 15% of cases of end-stage renal disease (ESRD). Arterial hypertension represents a frequent finding in patients suffering from glomerulonephritis or vasculitis and hypertension also serves as an indicator for these severe types of diseases. In addition, there are symptoms and signs like hematuria, proteinuria and renal failure. Especially, rapidly progressive glomerulonephritis (RPGN) constitutes a medical emergency and must not be missed by treating physicians. This disease can either occur limited to the kidneys or in the context of a systemic inflammatory disorder, like a vasculitis. If left untreated, RPGN can lead to a necrotizing destruction of glomeruli causing irreversible kidney damage within several months or even weeks. With respect to the immunologically caused vasculitis, there are - depending upon the severity and type of organ involved - many clinical warning signs to be recognized, such as arterial hypertension, hemoptysis, arthalgias, muscle pain, palpable purpura, hematuria, proteinuria and renal failure. In addition, constitutional signs, such as fever and loss of body weight may occur concurrently. Investigations of glomerulonephritis or vasculitis must contain a careful and complete examination of family history and medications used by the respective patient. Thereafter, a thorough clinical examination must follow, including skin, joints and measurement of arterial blood pressure. In addition, a spectrum of laboratory analyses is required in blood, such as full blood screen, erythrocyte sedimentation rate, CRP, creatinine, urea and glucose, and in urine, including urinalysis looking for hematuria, red cell casts and proteinuria. Importantly, proteinuria needs to be quantified by the utilization of a random urine sample. Proteinuria > 3g/d is diagnostic for a glomerular damage. These basic tests are usually followed by more specialized analyses, such as a screening for infections, including search for HIV, hepatitis B or C and various bacteria, and for systemic inflammatory diseases, including tests for antibodies, such as ANA, anti-dsDNA, ANCA, anti-GBM and anti-CCP. In cases of membranous nephropathy, antibodies against phospholipase-A2-receptor need to be looked for. Depending upon the given clinical circumstances and the type of disease, a reasonable tumor screening must be performed, especially in cases of membranous and minimal-change nephropathy. Finally, radiological examinations will complete the initial work-up. In most cases, at least an ultrasound of the kidney is mandatory. Thereafter, in most cases a renal biopsy is required to establish a firm diagnosis to define all treatment options and their chance of success. The elimination of a specific cause for a given glomerulonephritis or vasculitis, such as an infection, a malignancy or a drug-related side-effect, remains the key principle in the management of these diseases. ACE-inhibitors, angiotensin receptor-blockers, aldosteron antagonists and renin-inhibitors remain the mainstay in the therapy of arterial hypertension with proteinuria. Only in cases of persistently high proteinuria, ACE-inhibitors and angiotensin receptor blockers can be prescribed in combination. Certain types of glomerulonephritis and essentially all forms of vasculitis require some form of more specific anti-inflammatory therapy. Respective immunosuppressive drug regimens contain traditionally medications, such as glucocorticoids (e. g. prednisone), cyclosporine A, mycophenolate mofetil, cyclophosphamide, and azathioprine. With respect to more severe forms of glomerulonephritis and vasculitis, the antibody rituximab represents a new and less toxic alternative to cyclophosphamide. Finally, in certain special cases, like Goodpasture's syndrome or severe ANCA-positive vasculitis, a plasma exchange will be useful and even required.

Mechanism for active membrane fusion triggering by morbillivirus attachment protein.

The paramyxovirus entry machinery consists of two glycoproteins that tightly cooperate to achieve membrane fusion for cell entry: the tetrameric attachment protein (HN, H, or G, depending on the paramyxovirus genus) and the trimeric fusion protein (F). Here, we explore whether receptor-induced conformational changes within morbillivirus H proteins promote membrane fusion by a mechanism requiring the active destabilization of prefusion F or by the dissociation of prefusion F from intracellularly preformed glycoprotein complexes. To properly probe F conformations, we identified anti-F monoclonal antibodies (MAbs) that recognize conformation-dependent epitopes. Through heat treatment as a surrogate for H-mediated F triggering, we demonstrate with these MAbs that the morbillivirus F trimer contains a sufficiently high inherent activation energy barrier to maintain the metastable prefusion state even in the absence of H. This notion was further validated by exploring the conformational states of destabilized F mutants and stabilized soluble F variants combined with the use of a membrane fusion inhibitor (3g). Taken together, our findings reveal that the morbillivirus H protein must lower the activation energy barrier of metastable prefusion F for fusion triggering.

Green Wireless-Energy Efficiency in Wireless Networks

Wireless networks have become more and more popular because of ease of installation, ease of access, and support of smart terminals and gadgets on the move. In the overall life cycle of providing green wireless technology, from production to operation and, finally, removal, this chapter focuses on the operation phase and summarizes insights in energy consumption of major technologies. The chapter also focuses on the edge of the network, comprising network access points (APs) and mobile user devices. It discusses particularities of most important wireless networking technologies: wireless access networks including 3G/LTE and wireless mesh networks (WMNs); wireless sensor networks (WSNs); and ad-hoc and opportunistic networks. Concerning energy efficiency, the chapter discusses challenges in access, wireless sensor, and ad-hoc and opportunistic networks.

Renal function can be impaired in children with primary hyperoxaluria type 3

BACKGROUND Primary hyperoxaluria type 3 (PH3) is characterized by mutations in the 4-hydroxy-2-oxoglutarate aldolase (HOGA1) gene. PH3 patients are believed to present with a less severe phenotype than those with PH1 and PH2, but the clinical characteristics of PH3 patients have yet to be defined in sufficient detail. The aim of this study was to report our experience with PH3. METHODS Genetic analysis of HOGA1 was performed in patients with a high clinical suspicion of PH after the presence of mutations in the alanine-glyoxylate aminotransferase gene had been ruled out. Clinical, biochemical and genetic data of the seven patients identified with HOGA1 mutations were subsequently retrospectively reviewed. RESULTS Among the seven patients identified with HOGA1 mutations the median onset of clinical symptoms was 1.8 (range 0.4-9.8) years. Five patients initially presented with urolithiasis, and two other patients presented with urinary tract infection. All patients experienced persistent hyperoxaluria. Seven mutations were found in HOGA1, including two previously unreported ones, c.834 + 1G > T and c.3G > A. At last follow-up, two patients had impaired renal function based on estimated glomerular filtration rates (GFRs) of 77 and 83 mL/min per 1.73 m(2), respectively. CONCLUSIONS We found that the GFR was significantly impaired in two of our seven patients with PH3 diagnosed during childhood. This finding is in contrast to the early-impaired renal function in PH1 and PH2 and appears to refute to preliminary reassuring data on renal function in PH3.

The sutureless aortic valve at 1 year: A large multicenter cohort study

OBJECTIVE Sutureless aortic valve replacement (AVR) offers an alternative to standard AVR in aortic stenosis. This prospective, single-arm study aimed to demonstrate safety and effectiveness of a bovine pericardial sutureless aortic valve at 1 year. METHODS From February 2010 to September 2013, 658 patients (mean age 78.3 ± 5.6 years; 40.0% octogenarian; 64.4% female; mean Society of Thoracic Surgeons score 7.2 ± 7.4) underwent sutureless AVR in 25 European centers. Concomitant cardiac procedures were performed in 29.5% and minimally invasive cardiac surgery in 33.3%. RESULTS One-year site-reported event rates were 8.1% for all-cause mortality, 4.5% for cardiac mortality, 3.0% for stroke, 1.9% for valve-related reoperation, 1.4% for endocarditis, and 0.6% for major paravalvular leak. No valve thrombosis, migration, or structural valve deterioration occurred. New York Heart Association class improved at least 1 level in 77.5% and remained stable (70.4% New York Heart Association class I or II at 1 year). Mean effective orifice area was 1.5 ± 0.4 cm(2); pressure gradient was 9.2 ± 5.0 mm Hg. Left ventricular mass decreased from 138.5 g/m(2) before surgery to 115.3 g/m(2) at 1 year (P < .001). Echocardiographic core laboratory findings confirmed that paravalvular leak was rare and remained stable during follow-up. CONCLUSIONS The Perceval sutureless valve resulted in low 1-year event rates in intermediate-risk patients undergoing AVR. New York Heart Association class improved in more than three-quarters of patients and remained stable. These data support the safety and efficacy to 1 year of the Perceval sutureless valve in this intermediate-risk population.