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Rapid advancements in space geodetic technology have generated an abundance of geodetic-quality datasets from various techniques Α combination of multi-technique datasets can provide a novel insight on tropospheric error mitigation and atmospheric studies. This study explores the use of augmenting GNSS and DORIS datasets for estimating tropospheric delay. DORIS is widely utilized for various geodetic applications such as precise orbit determination of satellites and space missions, geodetic reference frame definition, modeling of the earth's gravity field, sea level and ocean circulation studies. While current DORIS analysis tools provide advanced features and robust data processing capabilities, they are not open source and are difficult to obtain.The study describes the design of an open-source, in-house DORIS processing software as well as an innovative approach to tropospheric path delay estimation in which datasets from GNSS and DORIS are combined and processed to produce final sets of ZPD and coordinates estimates. The software utilizes the DORIS RINEX v3.0 data file format, which enables the full exploitation of the system's modernized features, including multi-channel pseudorange and carrier-phase observations. In accordance with IDS and IERS recommendations and standards, the software is designed to produce high-quality results. Special care is taken to handle system-specific noise characteristics and observation weighting. Upon completion, the software will constitute a free and open-source solution for the DORIS community, offering a valuable resource for the advancement of geodetic research., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

This work presents an analysis of dynamic displacements observed on GNSS stations in the Aegean region, induced by the two earthquakes with magnitude 7.8 and 7.5, in Southern Turkey on 06/02/2023. For this reason, GNSS data of 1Hz observation rate from continuously operating stations located across the Aegean Sea and the mainland of Greece was processed using Precise Point Positioning method. Position time-series were analyzed to estimate the amplitude of the displacement, the direction in which the maximum displacement is observed and the time of occurrence. Furthermore, emphasis is given on comparing the characteristics of the displacements observed between the two events and examine a possible correlation with the corresponding faults’ geometry for each separate event. An additional evaluation of the kinematic behavior of permanent GNSS stations located in proximity of the Hellenic subduction zone with the African plate, the latter sharing a tectonic boundary with both the Arabian and Anatolian plates was conducted. The results of this work discuss the effects that strong earthquakes can have at distances over 1000 km and along active tectonic boundaries, implying the larger-scale impact of such geohazards., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

Dionysos Satellite Observatory (DSO) of the National Technical University of Athens (NTUA) undertook the monitoring of the Corinth Gulf region through GPS/GNSS stations and the development of a multidisciplinary platform. The DSO automatic GNSS data processing platform has been significantly upgraded the last year to estimate a number of parameters per day. The most critical is the coordinates of each station, estimated every day, in the IGb14 reference frame. Data from 36 permanent GNSS stations, installed in the wide area of Corinth Gulf, were analyzed. Position time series were processed for all stations where the available data had a time period greater than 2.5 year for the estimation of the velocity field. Time series analysis follows an iterative process, where at each step one and/or more new parameters are tested based on their statistical significance. Linear trend, seasonal signal and power spectral density ware estimated. A dense velocity field was produced, with respect to IGb2014 for stations with data availability greater than 2.5 years. A velocity field also with respect to a stable Europe was calculated. Different kinematic models were considered to approximate the behavior of the solid crust in the region are presented. The StrainTool software is used with minor modifications, to estimate strain rates, dilatation and the other parameters of the strain tensor on a grid with different grid steps. Finally, the results are available on the web portal that has been developed as part of the DSO website., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

The aim of the present study is the development and evaluation of the physicochemical properties of chimeric hydrogenated soya phosphatidylcholine (HSPC) and egg phosphatidylcholine (EggPC) liposomes with incorporated triblock copolymer Poloxamer P407 (P407). The physicochemical assay was held in water HPLC-grade and Foetal Bovine Serum (FBS), in order to determine whether these systems can be used as drug or antigen delivery nanosystems. Dynamic and electrophoretic light scattering (DLS/ELS) techniques were used for the measurement of the hydrodynamic diameter, the polydispersity index, and the ζ-potential of the prepared nanosystems. The incorporation of the P407 resulted in a size reduction of all systems. A decrease in the hydrodynamic diameter and polydispersity index were also found as a result of increasing the storage temperature from 4 °C to 25 °C, attributed to P407. The experiments that were carried out in FBS, showed that the addition of P407 improved systems stealth properties. Concluding, we propose P407 as a promising alternative to PEG in the development of lipid nanoparticles with optimized bio- and shelf-stability. © 2021 Informa UK Limited, trading as Taylor & Francis Group.

A skilled control of postural stability is fundamental in many of the actions performed by volleyball athletes. The effectiveness in serving, forearm passing or setting the ball is affected by the athlete’s ability to control their dynamic balance. When referring to team sports, earlier studies have shown that balance and proprioception training have the potential to induce performance enhancement in selected components of physical fitness and some technical skills but only few of them focus on the field of volleyball. Therefore, the purpose of this study is to investigate the effect of a balance and proprioception training program on dynamic balance and volleyball skills of female volleyball players aged 13-15 years. The sample is consisted by 18 participants who were divided into an experimental group (EG, N=10) and a control group (CG, N=8). In addition to volleyball training, the EG followed an 8-week proprioception and balance training program (3 times/week). Dynamic balance test results were obtained, and participants were rated for the movement outcome (performance score: PS) and movement form (Technique score: TS) of their motor tasks in volleyball skills. Two-factor ANOVA with repeated measurements on the second factor was used to examine the effects of groups and measurements and their interactions. The dynamic balance of the EG showed a significant improvement (p = 0.009). There was an increase in PS for serve (p = 0.022) and TS in forearm-passing (p = 0.001) for the EG, but not for the setting skill (p > 0.05). The study reveals that a targeted proprioception and balance training program can improve the dynamic balance of youth female volleyball players and contribute to the improvement of the movement form of the forearm passing and the movement outcome of the serve skill. © JPES.

While classic vaccines have proved greatly efficacious in eliminating serious infectious diseases, innovative vaccine platforms open a new pathway to overcome dangerous pandemics via the development of safe and effective formulations. Such platforms play a key role either as antigen delivery systems or as immune-stimulators that induce both innate and adaptive immune responses. Liposomes or lipid nanoparticles, virus-like particles, nanoemulsions, polymeric or inorganic nanoparticles, as well as viral vectors, all belong to the nanoscale and are the main categories of innovative vaccines that are currently on the market or in clinical and preclinical phases. In this paper, we review the above formulations used in vaccinology and we discuss their connection with the development of safe and effective prophylactic vaccines against SARS-CoV-2. © 2021 Elsevier B.V.

The island of Chalki, located W of Rhodos, belongs to the East Aegean Islands and is situated at the E part of the South Aegean Island Arc. The flora of Chalki consists of 519 vascular plant taxa, 29 of which are under statutory protection, 22 are Greek endemics and 109 are reported here for the first time. We show that Chalki has the second highest percentage of Greek endemics in the phytogeographical region of the East Aegean Islands. The known distribution of Limonium ocymifolium, L. sitiacum and Phoenix theophrasti is expanded, being reported for the first time for the phytogeographical region of the East Aegean Islands. Finally, we assess for the first time the conservation status of Allium chalkii, a single-island endemic, by biomonitoring its populations. © 2016 The Authors.

Purpose: To evaluate the prevalence of bacteremia after mask ventilation, laryngoscopy, and endotracheal intubation before induction of general anesthesia and to discover any correlation between traumatic manipulations and bacteremia. The specific bacteria responsible, knowledge of which may guide the prophylactic use of antibiotics, also were investigated. Methods: Fifty patients were enrolled. Three 10-mL blood samples were collected from a peripheral vein 10 min before induction of anesthesia, 10 min after mask ventilation, and 10 min after intubation. All samples were placed in aerobic and anaerobic bottles for culture and bacterial identification. Results: Cultures received 10 min after intubation were positive in 12% of patients. The following strains were isolated: Escherichia coli in two cases, Staphylococcus aureus in three cases, and Peptostreptococcus anaerobius in one case. A strong positive correlation was found between difficult intubation and bacteremia. No correlation between bacteremia and easy intubation or between bacteremia and face mask ventilation was identified. Conclusion: Traumatic manipulations during difficult laryngoscopy and endotracheal intubation could cause bacteremia. This finding may justify and guide prophylactic use of antibiotics. © 2008 Mary Ann Liebert, Inc.