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Background: Rapidly progressive dementias (RPDs) are dementias that progress subacutely over a time period of weeks to months. Primary Sjögren’s syndrome (pSS) is an autoimmune disease that can affect any organ system and may present with a wide range of clinical features that may mimic a plethora of medical conditions and, in rare cases, may manifest as RPD. We describe a unique case of pSS, in which rapidly progressive dementia (RPD) was the first disease manifestation, and the patient’s radiological and electroencephalogram findings were compatible with Creutzfeldt- Jakob disease (CJD). Case presentation: Here, we report a 58-year-old woman who presented with cognitive impairment rapidly deteriorating over the last 6 months prior to admission. Brain MRI and EEG were indicative of CJD. However, CSF 14-3-3 and tau/phospho tau ratio were within normal limits and therefore alternative diagnoses were considered. Blood tests were significant for positive antinuclear antibodies, anti-ENA, and anti-SSA and a lip biopsy was consistent with pSS. The patient was started on intravenous steroids followed by oral prednisone taper, which prevented further deterioration. Conclusions: This rare case expands the spectrum of neurological manifestations in pSS and highlights the importance of considering pSS in the differential diagnosis of RPDs in order to avoid misdiagnosis and provide appropriate treatment in a timely fashion.

Objective In 2008, the radiofrequency ablation (RFA) procedures registry of the Hellenic Society of Cardiology was created. This online database allowed electrophysiologists around the country to input data for all performed ablation procedures. The aim of this study is to provide a thorough report and interpretation of the data submitted to the registry between 2008 and 2018. Methods In 2008, a total of 27 centers/medical teams in 24 hospitals were licensed to perform RFA in Greece. By 2018, the number had risen to 31. Each center was tasked with inserting their own data into the registry, which included patient demographics (anonymized), type of procedure and technique, complications, and outcomes. Results A total of 18587 procedures in 17900 patients were recorded in the period of 2008-2018. By 2018, slightly more than 70% of procedures were performed in 7 high-volume centers (>100 cases/year). The most common procedure since 2014 was atrial fibrillation ablation, followed by atrioventricular nodal reentry tachycardia ablation. Complication rates were low, and success rates remained high, whereas the 6-month relapse rates declined steadily. Conclusion This online RFA registry has proved that ablation procedures in Greece have reached a very high standard, with results and complication rates comparable to European and American standards. Ablation procedures for atrial fibrillation are increasing constantly, with it being the most common intervention over the last 6-year period, although the absolute number of procedures still remains low, compared to other European countries.

Objective:Rapid right ventricular pacing during balloon aortic valvuloplasty is commonly used to achieve balloon stability in children and adults. There is no consensus for the use of the technique in neonates and infants. We sought to review our institutional experience with rapid right ventricular pacing-assisted balloon aortic valvuloplasty across all age groups and evaluate the safety and effectiveness of the technique in the sub-group of neonates and infants Methods:Retrospective study between February, 2011 and February, 2020.Results:A total of 37 patients (Group I: 21 neonates/infants Conclusions:Rapid right ventricular pacing can be expanded in neonates and infants to potentially decrease the incidence of aortic regurgitation and reintervention rates, hence avoiding high-risk surgical bail-out procedures for severe aortic regurgitation in the first year of life. Myocardial ischemia may predispose to ventricular dysrhythmias during rapid right ventricular pacing.

West Nile virus (WNV) is a mosquito-borne RNA flavivirus which caused several epidemics worldwide. The year 2018 was a WNV record year for Europe, including Greece, with earlier and longer transmission season with higher than the previous number of cases. It has been proposed that some simple biochemical markers may be helpful for the recognition of WNV neuroinvasive disease, its differential from other neurological infectious diseases and prognosis. We describe four cases that suffered from WNV meningitis and/or encephalitis hospitalized in 2018 in a tertiary hospital in Thessaloniki, Greece, and investigate the importance of simple biomarkers for the recognition of WNV etiology.

Operational wildland fire propagation models typically are uncoupled from the wind field or rely solely on estimations from an atmospheric model and/or meteorological observations. This leads to a frozen wind field with a high degree of uncertainty, and therefore to results drifting from the ground truth. On the other hand, a fully-coupled model is not viable for operational use due to the enormous computing effort required. This article proposes the use of real-time measurements from a drone swarm to enhance the results of a one-way coupled physics-based model (FireProM-F) to mimic the two-way coupling of fire and atmosphere. In the absence of actual measurements, synthetic data is used at the early stages of this research. The latter is generated using the WFDS levelset model with two-way fire-atmosphere coupling at various phases of the fire. Finally, the 'measured' wind field will be integrated into the target model to determine its effect on the outcomes.

The present study investigates the effect of different reaction times on the crystallinity, surface morphology and size of iron oxide nanoparticles. In this synthetic system, aqueous iron (III) nitrate (Fe (NO3)3·9H2O) nonahydrate, provided the iron source and triethylamine was the precipitant and alkaline agent. The as-synthesised iron oxide nanoparticles were characterised by X-ray diffraction (XRD), Rietveld analysis, Scanning Electron Microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). Prolonged reaction times indicated the change on nanoparticle shape from elongated nanorods to finally distorted nanocubes. Analysis on the crystallinity of the iron oxide nanoparticles suggest that the samples mainly consist of two phases, which are Goethite (α-FeOOH) and Hematite (α-Fe2O3) respectively.

Photoelectrochemical cells have been constructed with photoanodes based on mesoporous titania deposited on transparent electrodes and sensitized in the Visible by nanoparticulate CdS or CdS combined with CdSe. The cathode electrode was an air&ndash, breathing carbon cloth carrying nanoparticulate carbon. These cells functioned in the Photo Fuel Cell mode, i.e., without bias, simply by shining light on the photoanode. The cathode functionality was governed by a two-electron oxygen reduction, which led to formation of hydrogen peroxide. Thus, these devices were employed for photoelectrocatalytic hydrogen peroxide production. Two-compartment cells have been used, carrying different electrolytes in the photoanode and cathode compartments. Hydrogen peroxide production has been monitored by using various electrolytes in the cathode compartment. In the presence of NaHCO3, the Faradaic efficiency for hydrogen peroxide production exceeded 100% due to a catalytic effect induced by this electrolyte. Photocurrent has been generated by either a CdS/TiO2 or a CdSe/CdS/TiO2 combination, both functioning in the presence of sacrificial agents. Thus, in the first case ethanol was used as fuel, while in the second case a mixture of Na2S with Na2SO3 has been employed.

Photoelectrochemical production of hydrogen peroxide was studied by using a cell functioning with a WO3 photoanode and an air breathing cathode made of carbon cloth with a hydrophobic layer of carbon black. The photoanode functioned in the absence of any sacrificial agent by water splitting, but the produced photocurrent was doubled in the presence of glycerol or ethanol. Hydrogen peroxide production was monitored in all cases, mainly in the presence of glycerol. The presence or absence of the organic fuel affected only the obtained photocurrent. The Faradaic efficiency for hydrogen peroxide production was the same in all cases, mounting up to 74%. The duplication of the photocurrent in the presence of biomass derivatives such as glycerol or ethanol and the fact that WO3 absorbed light in a substantial range of the visible spectrum promotes the presently studied system as a sustainable source of hydrogen peroxide production.

Photoelectrocatalytic hydrogen production was studied by using a photoelectrochemical cell where the photoanode was made by depositing on FTO electrodes either a nanoparticulate WO3 film alone or a bilayer film made of nanoparticulate WO3 at the bottom covered with a nanoparticulate TiO2 film on the top. Both the electric current and the hydrogen produced by the photoelectrocatalysis cell substantially increased by adding the top titania layer. The presence of this layer did not affect the current-voltage characteristics of the cell (besides the increase of the current density). This was an indication that the flow of electrons in the combined semiconductor photoanode was through the WO3 layer. The increase of the current was mainly attributed to the passivation of the surface recombination sites on WO3 contributing to the limitation of charge recombination mechanisms. In addition, the top titania layer may have contributed to photon absorption by back scattering of light and thus by enhancement of light absorption by WO3. Relatively high charge densities were recorded, owing both to the improvement of the photoanode by the combined photocatalyst and to the presence of ethanol as the sacrificial agent (fuel), which affected the recorded current by &ldquo, current doubling&rdquo, phenomena. Hydrogen was produced under electric bias using a simple cathode electrode made of carbon paper carrying carbon black as the electrocatalyst. This electrode gave a Faradaic efficiency of 58% for hydrogen production.

Hydrogen and hydrogen peroxide have been photoelectrocatalytically produced by electrocatalytic reduction using simple carbon electrodes made by depositing a mesoporous carbon film on carbon cloth. Visible-light-absorbing photoanodes have been constructed by depositing mesoporous CdS/TiO2 or WO3 films on transparent fluorine-doped tin oxide (FTO) electrodes. Both produced substantial photocurrents of up to 50 mA in the case of CdS/TiO2 and 25 mA in the case of WO3 photoanodes, and resulting in the production of substantial quantities of H2 gas or aqueous H2O2. Maximum hydrogen production rate was 7.8 &micro, mol/min, and maximum hydrogen peroxide production rate was equivalent, i.e., 7.5 &micro, mol/min. The same reactor was employed for the production of both solar fuels, with the difference being that hydrogen was produced under anaerobic and hydrogen peroxide under aerated conditions. The present data promote the photoelectrochemical production of solar fuels by using simple inexpensive materials for the synthesis of catalysts and the construction of electrodes.

The aim of this study was to examine the effect of the secondary biological treatment plant effluent administration on the kidneys, urinary bladder, and testis of Wistar rats in relation to lead (Pb) and cadmium (Cd) accumulation, since such an effluent is used for irrigation of edible plants. Male Wistar rats, randomly assigned into 5 groups, were treated with domestic sewage effluent (DSE) for 24 months. Cadmium and lead concentrations in the DSE, rats' tissues, and urine were estimated by means of atomic spectroscopy. Lead was rapidly accumulated in high amounts in rats' kidney and to a lesser extent in the testis whereas Cd concentration was raised in all tissues examined. Deposition of Cd and Pd in the kidney of the rats resulted in profound damage over time. The results showed that long-term administration to DSE as drinking water exposes living organisms to urogenital stress related to heavy metal concentration and pH of the effluent.

Photoelectrochemical production of hydrogen peroxide has been studied by using a two-compartment photoelectrochemical cell operating in the Photo(catalytic) Fuel Cell mode, i.e. it run without any external bias, simply by shining light and generating current. The photoanode was made of CdS quantum dots deposited on nanocrystalline titania, which was first formed on a transparent fluorine doped tin oxide electrode. The photoanode operated in an alkaline environment with added ethanol as model fuel. An air-breathing cathode was made by depositing carbon black on carbon cloth, without any additives of particular functionalities. Best results were obtained by using a neutral electrolyte (Na2SO4) in the cathode compartment. Hydrogen peroxide was produced during cell operation in a cumulative manner adding up to 1400 mg/l (41 mM) in three hours of operation. The rate of hydrogen peroxide production during this period of time remained practically constant and was 5.7 μmole/min, which corresponds to an average Faradaic efficiency of 74%. These data characterize a system with satisfactory performance that may be used for solar fuel production.

Authorization bugs, when present in online social networks, are usually caused by missing or incorrect authorization checks and can allow attackers to bypass the online social network's protections. Unfortunately, there is no practical way to fully guarantee that an authorization bug will never be introduced—even with good engineering practices—as a web application and its data model become more complex. Unlike other web application vulnerabilities such as XSS and CSRF, there is no practical general solution to prevent missing or incorrect authorization checks. In this paper we propose Invariant Detector (IVD), a defense-in-depth system that automatically learns authorization rules from normal data manipulation patterns and distills them into likely invariants. These invariants, usually learned during the testing or pre-release stages of new features, are then used to block any requests that may attempt to exploit bugs in the social network's authorization logic. IVD acts as an additional layer of defense, working behind the scenes, complementary to privacy frameworks and testing. We have designed and implemented IVD to handle the unique challenges posed by modern online social networks. IVD is currently running at Facebook, where it infers and evaluates daily more than 200,000 invariants from a sample of roughly 500 million client requests, and checks the resulting invariants every second against millions of writes made to a graph database containing trillions of entities. Thus far IVD has detected several high impact authorization bugs and has successfully blocked attempts to exploit them before code fixes were deployed.

Security concerns are widely seen as an obstacle to the adoption of cloud computing solutions. Information Flow Control (IFC) is a well understood Mandatory Access Control methodology. The earliest IFC models targeted security in a centralised environment, but decentralised forms of IFC have been designed and implemented, often within academic research projects. As a result, there is potential for decentralised IFC to achieve better cloud security than is available today. In this paper we describe the properties of cloud computing—Platform-as-a-Service clouds in particular—and review a range of IFC models and implementations to identify opportunities for using IFC within a cloud computing context. Since IFC security is linked to the data that it protects, both tenants and providers of cloud services can agree on security policy, in a manner that does not require them to understand and rely on the particulars of the cloud software stack in order to effect enforcement.

With the use of external cloud services such as Google Docs or Evernote in an enterprise setting, the loss of control over sensitive data becomes a major concern for organisations. It is typical for regular users to violate data disclosure policies accidentally, e.g. when sharing text between documents in browser tabs. Our goal is to help such users comply with data disclosure policies: we want to alert them about potentially unauthorised data disclosure from trusted to untrusted cloud services. This is particularly challenging when users can modify data in arbitrary ways, they employ multiple cloud services, and cloud services cannot be changed. To track the propagation of text data robustly across cloud services, we introduce imprecise data flow tracking, which identifies data flows implicitly by detecting and quantifying the similarity between text fragments. To reason about violations of data disclosure policies, we describe a new text disclosure model that, based on similarity, associates text fragments in web browsers with security tags and identifies unauthorised data flows to untrusted services. We demonstrate the applicability of imprecise data tracking through BrowserFlow, a browser-based middleware that alerts users when they expose potentially sensitive text to an untrusted cloud service. Our experiments show that BrowserFlow can robustly track data flows and manage security tags for documents with no noticeable performance impact.

The azo dye Basic Blue 41 was subjected to photocatalytic and photoelectrocatalytic degradation using nanopararticulate titania films deposited on either glass slides or Fluorine doped Tin Oxide (FTO) transparent electrodes. The degradation was carried out by irradiating titania films with weak ultraviolet (UVA) radiation. The degradation was faster when using FTO as a titania support even without bias and was further accelerated under forward electric bias. This result was explained by enhanced electron-hole separation even in the case of the unbiased titania/FTO combination. This system for organic material photocatalytic degradation was also successfully applied to the degradation of the anti-inflammatory drug piroxicam, which demonstrated a well distinguished degradation behavior in going from a plain glass support to unbiased and biased FTO. The degradation pathway of piroxicam has been additionally studied using liquid chromatography-accurate mass spectrometry analysis.

Plasma atrial natriuretic peptide (ANP) and zinc levels, as well as heart tissue zinc concentrations were determined, in male Wistar rats after the exposure of 114 rats at low temperature (4 degrees C) and 95 rats at high temperature (35-36 degrees C) for 28 d. Plasma ANP was estimated by radioimmunoassay and Zn2+ concentrations by atomic absorption spectrometry. Values were compared to a control group exposed at 20-22 degrees C (76 rats). Plasma ANP and Zn2+ levels, as well as heart tissue Zn2+ concentrations of control rats did not show statistically significant variations during the study, whereas rats exposed to cold and hot ambients showed significant variations of the parameters. A significant increase of plasma ANP and plasma zinc and heart tissue Zn2+ concentrations developed during cold exposure, whereas a gradual decrease of plasma ANP and Zn2+ levels was revealed during hot adaptation. Results also indicate that plasma ANP and zinc levels are proportionally related, whereas there is an inverse relationship between plasma ANP levels and heart Zn2+ concentrations, in both cold and hot exposed rats. In conclusion, our results show that ANP in relation to zinc probably play an important role in cold and hot acclimatization of rats. Biol Trace Elem Res

A major obstacle for the adoption of cloud services in enterprises is the potential loss of control over sensitive data. Companies often have to safeguard a subset of their data because it is crucial to their business or they are required to do so by law. In contrast, cloud service providers handle enterprise data without providing guarantees and may put confidentiality at risk. In order to maintain control over their sensitive data, companies typically block all access to a wide range of cloud services at the network level. Such restrictions significantly reduce employee productivity while offering limited practical protection in the presence of malicious employees.In this paper, we suggest a practical mechanism to ensure that an enterprise maintains control of its sensitive data while employees are allowed to use cloud services. We observe that most cloud services use HTTP as a transport protocol. Since HTTP offers well-defined methods to transfer files, inspecting HTTP messages allows the propagation of data between the enterprise and cloud services to be monitored independently of the implementation of specific cloud services. Our system, CloudFilter, intercepts file transfers to cloud services, performs logging and enforces data propagation policies. CloudFilter controls where files propagate after they have been uploaded to the cloud and ensures that only authorised users may gain access. We show that CloudFilter can be applied to control data propagation to Dropbox and GSS, describing the realistic data propagation policies that it can enforce.

Part 9: Industry; International audience; Web applications in many domains such as healthcare and finance must process sensitive data, while complying with legal policies regarding the release of different classes of data to different parties. Currently, software bugs may lead to irreversible disclosure of confidential data in multi-tier web applications. An open challenge is how developers can guarantee these web applications only ever release sensitive data to authorised users without costly, recurring security audits.Our solution is to provide a trusted middleware that acts as a “safety net” to event-based enterprise web applications by preventing harmful data disclosure before it happens. We describe the design and implementation of SafeWeb, a Ruby-based middleware that associates data with security labels and transparently tracks their propagation at different granularities across a multi-tier web architecture with storage and complex event processing. For efficiency, maintainability and ease-of-use, SafeWeb exploits the dynamic features of the Ruby programming language to achieve label propagation and data flow enforcement. We evaluate SafeWeb by reporting our experience of implementing a web-based cancer treatment application and deploying it as part of the UK National Health Service (NHS).

Linking security policy into event-based systems allows formal reasoning about information security. In the applications we address, highly confidential data must be shared both dynamically and for historical analysis. Principals with rights to access the data may be widely distributed, existing in a federation of independent administrative domains. Domain managers are responsible for the data held within domains and transmitted from them; security policy must be specified and enforced in order to meet these obligations. We motivate the event-driven paradigm and take healthcare as a running example, because the confidentiality of healthcare data must be guaranteed over many years. We first consider how to enforce authorisation policy at the client level through parametrised role-based access control (RBAC), taking context into account. We then discuss the additional requirements for secure information flow through the infrastructure components that contribute to communication within and between distributed domains. Finally, we show how this approach supports reasoning about event security in large-scale distributed systems.

Complex middleware frameworks are made out of interacting components which may include bugs. These frameworks are often extended to provide additional features by third-party extensions that may not be completely trusted and, as a result, compromise the security of the whole platform. Aiming to minimize these problems, we propose a demonstration of PrivateFlow, a publish/subscribe prototype supported by Decentralized Information Flow Control (DIFC). DIFC is a taint-tracking mechanism that can prevent components from leaking information. We will showcase a simple deployment of PrivateFlow that incorporates third-party untrusted components. In our demonstration, one of these components will try to leak sensitive information about the system's operation and it will fail once DIFC is activated.

This paper deals with the problem of selecting service instances to execute workflow processes by not only taking into consideration Quality of Service (QoS) constraints, posed by the end-users, but also the business relationships between different service providers. These business / strategic relationships, the providers have, may affect the parameters of the service instances regarding the offered QoS level, and therefore the relationships need to be modeled and expressed with specific metrics. In this paper we present an innovative algorithm that maps workflow processes to service instances by taking into account the aforementioned metrics during the selection process. We also demonstrate the operation of the implemented algorithm and evaluate its effectiveness using a scenario, based on a 3D image rendering application.

Although initially designed to cover the needs of computationally-intensive applications, Grid technology of nowadays aims at providing an infrastructure that can also serve the needs of the business domain. Taking into consideration that the available service providers may have business / strategic relationships, this paper focuses on describing an approach for modeling these relationships. Furthermore and since these relationships may affect the parameters regarding the offered Quality of Service (QoS) level, we present a metric for characterizing a service providers "friendliness". The latter can be used to promote the most positively influential providers and put aside those with a negative influence during a QoS-based selection process in Grid workflow management systems.

Lead and cadmium concentrations were measured in eggs of collonially nesting waterbirds with different position in the food chains of Greek wetlands of international importance. Differences were found between species in the levels of both lead and cadmium in the Evros and Axios Deltas attributable to their different diets. Nevertheless, the concentration in eggs was unrelated to the position of each species studied in its food chain. There was no significant difference in lead levels among four wetlands sampled for the cormorant and in Cd levels among three wetlands sampled for the Mediterranean gull, probably implying species-specific accumulation patterns. A higher lead pollution of the Axios Delta area was only reflected in the eggs of the Mediterranean gull. The very low concentrations of both metals found in the eggs may either suggest low environmental inputs or lack of sensitivity in using eggs as lead and cadmium biomonitors, thus a more sensitive bioindicator still remains to be found. Science of the Total Environment

Summarization: Co-combustion of two municipal waste materials (food waste and bio-solids) with an agricultural residue was carried out in a fluid bed unit, for investigating the thermal exploitation of these wastes for energy production. The reactivity of the fuels was studied by thermogravimetric analysis, while temperature profiles, gaseous emissions and combustion efficiency were determined under different operating conditions of the fluid bed reactor. By blending municipal solid waste or sewage sludge with olive stone burnout was improved, nevertheless even at high percentages of these wastes in the mixture combustion efficiency was very good, ranging between 98.5 and 99.5%. A reduction in excess air from 50 to 30%, or an increase in fuel feeding, resulted in higher SO2 and NOx emissions. SO2 levels from olive stone/municipal solid waste blends were negligible, while those of NOx exceeded emission guidelines. To meet legislation without any extra measures, generally the share of municipal solid waste in the mixture should be up to 10%, reactor loading for all mixtures below 0.72 kg/h and excess air over 40%. Presented on: Journal of the Energy Institute