Effect of cell residence time variance on the performance of an advanced paging algorithm

The use of advanced sequential paging algorithms has been suggested as a means to reduce the signaling cost in future mobile cellular networks. In a proposed algorithm (Koukoutsidis and Theologou, 2003), the system can use the additional information of the last interaction cell combined with a mobility model to predict the short-term location probabilities at the time of an incoming call arrival. The short-term location probabilities reduce the uncertainty in mobile user position and thus greatly improve the search. In this paper, an analytical model is derived that allows for a general distribution of cell residence times. By considering a Gamma distribution, we study the effect of the variance of cell residence times and derive useful results on the performance of the algorithm.Comment: 8 pages, 3 figure

Prediction of Soil Moisture from Remote Sensing Data

AbstractThis study evaluates the capability of soil water content predicted from remote sensing to indicate the soil/canopy water content at short time and space scale, through comparisons with daily soil moisture data determined in situ, using dielectric devices. Daily aqua moderate resolution imaging spectroradiometer (MODIS) normalized difference vegetation index (NDVI) and the diurnal (daytime and night time) land surface temperature difference (DLST) are employed to retrieving daily volumetric soil moisture content (θ) at Sparta experimental station, during the period June-August, of the years 2010, 2011, 2012 and 2014. Using the concept of apparent thermal inertia (ATI) in the remotely sensed topsoil moisture saturation index, daily θ is obtained from DLST and the volumetric saturated and residual soil moisture content and is compared with the experimental values of volumetric soil moisture content (SM) measured at various depths (10, 20, 30, 40, 60, 80 and 100cm). Simple relationships are also calibrated between SM and ATI or DLST or NDVI during the years 2010, 2011 and 2014 and are tested for predicting θ, during the year 2012. Especially the three first models predict θ satisfactorily as compared with the measured SM and hence they can offer a considerable guidance in irrigated agriculture and other related fields

Short Term Impacts of Harvesting 0perations on Soil Chemical Properties in a Mediterranean Oak Ecosystem

Soil physical and chemical properties can be seriously affected by forest operations. There is a knowledge gap on this topic for oak ecosystems, which can play a significant role in the context of multiple-use forestry. The main objective of this study was to analyse forest floor and topsoil changes (0–10 cm) two years after the application of small-scale thinning (50% reduction of basal area) and clear-cut operations using mules to carry harvested material in a Northern Greece oak (Quercus frainetto Ten)ecosystem. The total amount of forest floor (O1+O2 horizons) was reduced by 37.8% in the thinned and 30.8% in the clear-cut plots compared to control plots. These large reductions are mainly due to reduction in the O2 horizon in the treated plots. Decomposition was reduced in the treated plots, possibly due to the new drier conditions. Treatments increased the soil pH but not to a significant extent. No evidence of erosion was found in the experimental plots due to the protective function of the forest floor and the use of designated mule trails. The areal extent of soil compaction was limited to only 3% of the total area mainly due to the careful planning and implementation of animal skidding. Small differences in C (%) and Ν (%) were found among control, thinned and clear-cut plots. The limiting growth factors in Mediterranean oak ecosystems are soil depth and the seasonal change of soil moisture, especially during the summer dry period. More research on the definition of the optimum thinning degree and extraction systems in similar ecosystems will be important to satisfy the need to improve soil characteristics

Interrelated modulation of endothelial function in Behcet's disease by clinical activity and corticosteroid treatment

Corticosteroids are commonly used in empirical treatment of Behçet's disease (BD), a systemic inflammatory condition associated with reversible endothelial dysfunction. In the present study we aimed to dissect the effects of clinical disease activity and chronic or short-term corticosteroid treatment on endothelial function in patients with BD. In a case-control, cross-sectional study, we assessed endothelial function by endothelium dependent flow mediated dilatation (FMD) at the brachial artery of 87 patients, who either were or were not receiving chronic corticosteroid treatment, and exhibiting variable clinical disease activity. Healthy individuals matched for age and sex served as controls. Endothelial function was also assessed in a prospective study of 11 patients before and after 7 days of treatment with prednisolone given at disease relapse (20 mg/day). In the cross-sectional component of the study, FMD was lower in patients than in control individuals (mean ± standard error: 4.1 ± 0.4% versus 5.7 ± 0.2%, P = 0.003), whereas there was a significant interaction between the effects of corticosteroids and disease activity on endothelial function (P = 0.014, two-factor analysis of variance). Among patients with inactive BD, those who were not treated with corticosteroids (n = 33) had FMD comparable to that in healthy control individuals, whereas those treated with corticosteroids (n = 15) had impaired endothelial function (P = 0.023 versus the respective control subgroup). In contrast, among patients with active BD, those who were not treated with corticosteroids (n = 20) had lower FMD than control individuals (P = 0.007), but in those who were receiving corticosteroids (n = 19) the FMD values were comparable to those in control individuals. Moreover, FMD was significantly improved after 7 days of prednisolone administration (3.7 ± 0.9% versus 7.6 ± 1.4%, P = 0.027). Taken together, these results imply that although corticosteroid treatment may impair endothelial function per se during the remission phase of the inflammatory process, it restores endothelial dysfunction during active BD by counteracting the harmful effects of relapsing inflammation

Serum Levels of Surfactant Proteins in Patients with Combined Pulmonary Fibrosis and Emphysema (CPFE)

Introduction Emphysema and idiopathic pulmonary fibrosis (IPF) present either per se or coexist in combined pulmonary fibrosis and emphysema (CPFE). Serum surfactant proteins (SPs) A, B, C and D levels may reflect lung damage. We evaluated serum SP levels in healthy controls, emphysema, IPF, and CPFE patients and their associations to disease severity and survival. Methods 122 consecutive patients (31 emphysema, 62 IPF, and 29 CPFE) and 25 healthy controls underwent PFTs, ABG-measurements, 6MWT and chest HRCT. Serum levels of SPs were measured. Patients were followed-up for 1-year. Results SP-A and SP-D levels differed between groups (p = 0.006 and p= 26 ng/mL) presented a weak association with reduced survival (p = 0.05). Conclusion In conclusion, serum SP-A and SP-D levels were higher where fibrosis exists or coexists and related to disease severity, suggesting that serum SPs relate to alveolar damage in fibrotic lungs and may reflect either local overproduction or overleakage. The weak association between high levels of SP-B and survival needs further validation in clinical trials

Towards precision medicine in severe asthma:Treatment algorithms based on treatable traits

Asthma is a common disease, and although its clinical manifestations may be similar among patients, recent research discoveries have shown that it consists of several distinct clinical clusters or phenotypes, each with different underlying molecular pathways yielding different treatment responses. Based on these observations, an alternative approach - known as ‘precision medicine’ - has been proposed for the management of patients with severe asthma. Precision medicine advocates identification of treatable traits, linking them to therapeutic approaches targeting genetic, immunological, environmental, and/or lifestyle factors in individual patients. The main “goal” of this personalised approach is to enable choosing a treatment which will be more likely to produce a beneficial response in the individual patient rather than a ‘one size fits all’ approach. The aim of the present review is to discuss different ways of phenotyping asthma and to provide a rationale for treatment algorithms based on principles of precision medicine

Prediction of soil moisture from remote sensing data

This study evaluates the capability of soil water content predicted from remote sensing to indicate the soil/canopy water content at short time and space scale, through comparisons with daily soil moisture data determined in situ, using dielectric devices. Daily aqua moderate resolution imaging spectroradiometer (MODIS) normalized difference vegetation index (NDVI) and the diurnal (daytime and night time) land surface temperature difference (DLST) are employed to retrieving daily volumetric soil moisture content (theta) at Sparta experimental station, during the period June-August, of the years 2010, 2011, 2012 and 2014. Using the concept of apparent thermal inertia (ATI) in the remotely sensed topsoil moisture saturation index, daily theta is obtained from DLST and the volumetric saturated and residual soil moisture content and is compared with the experimental values of volumetric soil moisture content (SM) measured at various depths (10, 20, 30, 40, 60, 80 and 100 cm). Simple relationships are also calibrated between SM and ATI or DLST or NDVI during the years 2010, 2011 and 2014 and are tested for predicting theta, during the year 2012. Especially the three first models predict theta satisfactorily as compared with the measured SM and hence they can offer a considerable guidance in irrigated agriculture and other related fields. (C) 2016 The Authors. Published by Elsevier Ltd