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In future mobile networks, the evolution of optical transport architectures enabling the flexible, scalable interconnection of Baseband Units (BBUs) and Radio Units (RUs) with heterogeneous interfaces is a significant issue. In this paper, we propose a multi‐technology hybrid transport architecture that comprises both analog and digital‐Radio over Fiber (RoF) mobile network segments relying on a dynamically reconfigurable optical switching node. As a step forward, the integration of the discussed network layout into an existing mobile infrastructure is demonstrated, enabling the support of real‐world services through both standard digital and Analog–Intermediate‐ Frequency over Fiber (A‐IFoF)‐based converged fiber–wireless paths. Emphasis has been placed on the implementation of a real‐time A‐IFoF transceiver that is employed through a single embedded fully programmable gateway array (FPGA)‐based platform that serves as an Ethernet to Intermediate Frequency (IF) bridge for the transmission of legacy traffic over the analog network segment. The experimental evaluation of the proposed concept was based on the dynamic optical routing of the legacy Common Public Radio Interface (CPRI), 1.5 GBaud analog‐intermediate frequency‐over-fiber (A‐IFoF)/mmWave and 10 Gbps binary optical waveforms, showing acceptable error vector magnitude (EVM) values for the complex radio waveforms and error‐free operation for binary optical streams, with Bit Error Rate (BER) values less than 10−9. Finally, the end‐to‐end proof‐of‐concept demonstration of the proposed solution was achieved through the delivery of 4K video streaming and Internet Protocol (IP) calls over a mobile core network. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.

The complete transformation of the ICT domain driven by 5G network principles and capabilities, will impact significantly the path towards digitalization of many vertical industries, with modern railway transportations being one of them. In this context, Future Railway Mobile Communication System (FRMCS) service requirements and system principles are very well mapped to 5G service and network concepts associated with network performance, technology neutrality at various levels as well as network planning and deployment options. However, the flexibility of 5G networks implies that concepts are pinned down to deployment paradigms so that afore assertions are proved. The 5G-PPP project 5G-VICTORI aims at delivering a complete 5G solution suitable for railway environments and FRMCS services, along with experimentation deployments for testing and evaluation in operational railway environments. This paper discusses the service Key Performance Indicators (KPIs) and technical requirements and provides an overview of the proposed experimental deployment in an operational railway environment in the area of Patras, Greece. © 2021, IFIP International Federation for Information Processing.

The purpose of this study was to investigate the effectiveness of a resorbable alloplastic in situ hardening bone grafting material for alveolar ridge preservation in a swine model. Seven Landrace pigs were used. In each animal, the maxillary left and right deciduous second molars were extracted, and extraction sites were either grafted with a resorbable alloplastic in situ hardening bone substitute, composed of beta-tricalcium phosphate (β-TCP) granules coated with poly(lactic-co-glycolic) acid (PLGA), or left unfilled to heal spontaneously. Animals were euthanized after 12 weeks, and the bone tissue was analyzed histologically and histomorphometrically. Linear changes of ridge width were also clinically measured and analyzed. Pronounced bone regeneration was found in both experimental and control sites, with no statistically significant differences. At the experimental sites, most of the alloplastic grafting material was resorbed and remnants of the graft particles were severely decreased in size. Moreover, experimental sites showed, in a statistically nonsignificant way, less mean horizontal dimensional reduction of the alveolar ridge (7.69%) compared to the control sites (8.86%). In conclusion, the β-TCP/PLGA biomaterial performed well as a biocompatible resorbable in situ hardening bone substitute when placed in intact extraction sockets in this animal model. © 2018 Bentham Science Publishers B.V.All Rights Reserved.

This article presents a converged 5G network infrastructure and an overarching architecture to jointly support operational network and end-user services, proposed by the EU 5G PPP project 5G-XHaul. The 5G-XHaul infrastructure adopts a common fronthaul/backhaul network solution, deploying a wealth of wireless technologies and a hybrid active/passive optical transport, supporting flexible fronthaul split options. This infrastructure is evaluated through a novel modeling. Numerical results indicate significant energy savings at the expense of increased end-user service delay. © 2017 IEEE.

Background Studies have indicated that there is a positive and indirect relationship between physical activity (PA) and quality of life (QoL). The current study examined this relationship through a social cognitive model with consideration to the intermediary effects of exercise self-efficacy, and physical (PCS, physical component summary) and psychological (MCS, mental component summary) health. Additionally, this model was widened to include concepts from the ecological theory, and any causal associations among neighborhood environment, PA, and QoL. Methods Six hundred and eighty-four physically active adults (39.16 ± 13.52 years, mean ± SD), living in Athens, Greece, completed a series of questionnaires measuring PA, QoL, exercise self-efficacy, PCS, MCS, neighborhood environment, and family and friend support for PA. The examined models were analyzed using structural equation modeling. Results The social cognitive and ecological models proved to be of appropriate fit. Within the social cognitive model, PA positively affected QoL through the mediating effects of exercise self-efficacy, PCS, and MCS. With regards to the ecological model, neighborhood environment positively influenced QoL through the intermediary effects of family support for PA, exercise self-efficacy, PA, PCS, and MCS. Conclusion Results indicated that the most important mediators in the examined models were exercise self-efficacy and health. Further, findings demonstrated the role of neighborhood environment in enhancing PA and QoL. Future studies should be carried out applying longitudinal data for a better understanding of these associations over time. © 2017

This study examined the validity and reliability of Greek versions of two scales assessing family and friend support for exercise behaviour. Exploratory factor analyses (EFAs) and confirmatory factor analyses (CFAs) were performed in a sample of 360 students. Additionally, CFAs were applied in a second sample of 726 physically active adults. Finally, associations were examined among scales and physical activity, exercise self-efficacy, and socio-demographic variables. Results indicated (a) a two-factor model for the Family Support for Exercise Behaviour Scale, (b) a one-factor solution for the Friend Support for Exercise Behaviour Scale, (c) satisfactory reliability coefficients, and (d) associations among the scales and physical activity, self-efficacy and socio-demographic variables. Conclusively, the social support scales were valid and reliable. © Perceptual & Motor Skills 2014.

Background: in the Greek population, the association between obesity and Health-Related Quality of Life (HRQoL) has not been examined so far. Thus, the purpose of the present study is to explore obesity-related predictors of HRQoL in a sample of Greek healthy adults. Methods: a cross-sectional design was used. The sample consisted of three hundred twenty seven healthy men (N=105) and women (N=222), between the ages of 30 and 50 years (mean age=39.57 ± 6.68) who lived in Athens. Body mass index (BMI), waist to hip ratio (WHR), and body fat (BF) were assessed. HRQoL was evaluated using the short-form 36 (SF-36) health survey, which consists of eight subscales and two health factors (physical and psychological health). Socio-demographic variables and health-related behaviours were assessed by questionnaires. Separate hierarchical regression analyses were conducted to examine the associations between BMI, WHR, BF and SF-36 health survey subscales and factors. Results: socio-demographic and health-related variables were moderately associated with the HRQoL subscales and factors. Furthermore, after controlling the socio-demographic variables and health-related behaviours, (a) BMI negatively predicted the physical functioning, physical role, bodily pain, and social functioning subscales, as well as the physical health factor and (b) WHR and BF negatively predicted the physical functioning subscale. However, the obesity indexes did not predict other psychological health subscales. ConclusionS: the results indicated negative associations of BMI, WHR, BF with physical functioning and health in a sample of Greek healthy adults. Such data relating total and abdominal obesity to HRQoL, as assessed by BMI, WHR, and BF, have not been reported until now in the literature. One limitation of this study was that the sample size was relatively small and the results could not be generalized to the entire Greek population.

Background: The use of kidneys from elderly deceased donors has substantially increased organ supply, although it is associated with worse graft function and survival rates. The risk of kidneys from elderly donors as well as expanded criteria donors (ECDs) on kidney transplant outcome was investigated. Patients and methods: Seventy-five kidney transplants from ECDs over a 5-year period were reviewed retrospectively. Old age and increased donor risk variables were analyzed separately in relation to graft function and survival. Results: Sixty-four of 75 (85.3%) recipients had functioning grafts 5 years posttransplant. The overall actuarial graft survivals from 1 to 5 years were 87.5%, 68.1%, 57.3%, 55.4%, and 47.3%, respectively. Early graft function gave 47 (62.7%) kidneys remarkable actuarial survivals of 100.0%, 88.3%, 75.8%, 75.8%, and 68.4% at 1 to 5 years posttransplant, and 28 (37.3%) kidneys had delayed graft function with substantially decreased actuarial survival rates, ranging from 66.7% to 23.2%. Kidneys from elderly donors had considerable actuarial graft survival rates of 100.0%, 83.3%, 76.9%, 76.9%, and 67.0% from 1 to 5 years, respectively; these were the best graft survival rates compared with kidneys from the other donor categories. The other donor risk variables when associated with advanced age of any had an adverse effect on recipient graft function and survival, but no single risk variable alone, or a combination of any two, showed any statistically significant variability. Conclusion: Elderly kidney donors provided a substantial organ pool expansion without affecting patient and graft survival in many patients. ECDs can be utilized safely if adequate measures are taken. © 2011 Elsevier Inc.

Background The objective of this study was to examine whether there was an association between acute rejection (AR) and nitric oxide (NO) levels and also to evaluate the clinical impact of NO measurement as a noninvasive marker for early detection of AR. Methods Fifty consecutive patients aged 17-62 years old received a living-related kidney graft. Serum levels of total nitrite and nitrate (NOx) were measured 30 min after graft reperfusion (NOx 1) and on days 1 (NOx 2), 5 (NOx 3), and 10 (NOx 4) post-transplantation (Tx). If clinically indicated, graft biopsy was performed. Results Acute humoral rejection was diagnosed by biopsy on 3rd post-Tx day in one patient. His serum NOx 2 levels were remarkably higher (380%) compared with his NOx 1 measurement. At the same time, NOx 1-2 measurements in uncomplicated group showed lower levels (-12%). Additionally, during the first month post-Tx, 5 cases of acute cellular rejection (ACR) were diagnosed. The mean percent change of NOx 3-4 levels in ACR group was 180.7 versus 16.1 in uncomplicated patients (P

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Urological complications after renal transplantation increase morbidity, delay graft function, and occasionally lead to graft and/or patient loss. The aim of this study was to analyze the causes of and therapeutic approaches to urological complications in renal transplantation as they related to patient outcomes. A series of 1525 consecutive renal transplantations were performed over a 24-year period. Renal grafts were obtained in 814 cases from living-related and in 711 from cadaveric donors. A Lich-Gregoire ureterovesical reimplantation technique with minimal bladder wall dissection was employed in all cases. Ureteral stents were routinely used in cadaveric transplants and exceptionally among living-related grafts. Urological complications were classified according to the mechanism and site of urinary tract involvement: graft ureteropelvic junction obstruction/stenosis (A), ureteral obstruction/stenosis (B), ureterovesical anastomosis obstruction/stenosis (C), urinary leakage (D), and other (E). Overall, we encountered 96 urological complications (6.3%). Group C complications occurred in 29 cases (30.2%), followed by 27 cases (28.1%) for group B patients, 25 cases (26.0%) for group D, 12 cases (12.5%) for group A, and 3 cases (3.1%) for group E patients. Surgical intervention was required in 49 (51.0%) of all urological complications. The others (n = 47, 49.0%) were treated either conservatively or by minimally invasive procedures. A rapid diagnosis of urological complications, assisted by early posttransplant DTPA scans, routine ultrasonography, and especially prompt treatment, resulted in compensation of renal graft dysfunction in the vast majority (n = 90, 93.8%) of cases. Surgical techniques of graft retrieval and reimplantation are of utmost importance to minimize the incidence of urological complications. © 2008 Elsevier Inc. All rights reserved.