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Catalytic sulphur trioxide splitting is the highest-temperature (650-950oC), endothermic step of several sulphur-based thermochemical cycles targeted to production of hydrogen or solid sulphur. Concentrated solar power tower plants are an attractive renewable energy source to provide the necessary heat. Furthermore, the development of solar receivers capable of delivering solid or gaseous heat transfer fluids at these temperature ranges enable the implementation of such endothermic reactions in allothermally-heated reactors/heat exchangers placed away from the solar receiver. In this context, a 2-kW laboratory-scale shelland-tube reactor/heat exchanger to perform thermal sulphuric acid decomposition and catalytic sulphur trioxide splitting was in-house designed, built and tested with electrically heated bauxite particles, in the perspective of eventually coupling such a reactor with a centrifugal particle solar receiver. Thermal test runs demonstrated the in-principle feasibility of the concept. The temperatures reached were sufficient to ensure complete sulphuric acid evaporation. However, the ones in the SO3 splitting zone were of the order of 750°C, high enough to demonstrate SO3 splitting but not reaching the levels required for close-toequilibrium conversion of the Fe2O3 catalyst system used (~ 850oC). An improved version of the reactor is under construction incorporating design modifications based on lessons learned from the test campaigns, in the perspective of scaling up the process.

An engineered system that exhibits a variety of interesting properties, such as collective dynamics that are not inherited in their building blocks, is the artificial spin ice (ASI) meta-materials. The building block of such a system is a dipolar nanomagnet with sub-micrometer dimensions. These nanomagnets are arranged in specific designs usually in square or kagome shape and are coupled together by their magnetic interactions. With external magnetic fields, it is possible to create magnetic moments or monopoles that cause a frustration to the system. Because of the local interactions, those moments travel through the topology. The observation of such structures is a very challenging procedure, because of the extremely fast flipping process of the spins. This is why the researchers use mesoscopic systems with materials such as colloids or spheres of nanomagnets which are placed inside of islands in periodic lattices that generate frustration by design. The interactions between those nanomagnets are based on Coulomb forces and are usually modeled by Brownian equations. In this paper, we propose a simple yet effective Cellular Automata (CA) model that can describe effectively the dynamics between nanomagnets in a square lattice structure. The manipulation of the initial positions of nanomagnets via an external magnetic field and the movement of magnetic moments from one site to another are capable to create Boolean logic. Using the CA model we propose the design of logic gates, computing structures such as half adders and rewritable memory elements.

Inspired by the behavior of natural systems, Cellular Automata (CA) tackle the demanding long-distance information transfer of conventional computers by the massive parallel computation performed by a set of locally-coupled dynamical nodes. Although CA are envisioned as powerful deterministic computers, their intrinsic capabilities are expanded after the memristor’s probabilistic switching is introduced into CA cells, resulting in new hybrid deterministic and probabilistic memristor-based CA (MemCA). In the proposed MemCA hardware realization, memristor devices are incorporated in both the cell and rule modules, composing the very first all-memristor CA hardware, designed with mixed CMOS/Memristor circuits. The proposed implementation accomplishes high operating speed and reduced area requirements, exploiting also memristor as an entropy source in every CA cell. MemCA’s functioning is showcased in deterministic and probabilistic operation, which can be externally modified by the selection of programming voltage amplitude, without changing the design. Also, the proposed MemCA system includes a reconfigurable rule module implementation that allows for spatial and temporal rule inhomogeneity.

Through Random Telegraph Noise (RTN) analysis, valuable information can be provided about the role of defect traps in fine tuning and reading of the state of a nanoelectronic device. However, time domain analysis techniques exhibit their limitations in case where unstable RTN signals occur. These instabilities are a common issue in Multi-Level Cells (MLC) of resistive memories (ReRAM), when the tunning protocol fails to find a perfectly stable resistance state, which in turn brings fluctuations to the RTN signal especially in long time measurements and cause severe errors in the estimation of the distribution of time constants of the observed telegraphic events, i.e., capture/emission of carriers from traps. In this work, we analyze the case of the unstable filaments in silicon nitride-based ReRAM devices and propose an adaptive filter implementing a moving-average detrending method in order to flatten unstable RTN signals and increase sufficiently the accuracy of the conducted measurements. The τe and τc emission/capture time constants of the traps, respectively, are then calculated and a cross-validation through frequency domain analysis (Lorentzian fitting) was performed proving that the proposed method is accurate.

The influence of light on human physiology, including its non-image forming effects, has been recognized for several decades. A significant breakthrough in understanding these non-visual effects came with the discovery of a new type of photoreceptor: intrinsically photosensitive retinal ganglion cells. The circadian effects of light include the regulation of melatonin secretion, circadian entrainment, and an increase in body temperature. The scope of this paper is to present a benchmark for the evaluation of artificial lighting systems considering visual, circadian aspects and their energy efficiency. In other words, this paper demonstrates a holistic evaluation methodology for optimal luminaire selection by benchmarking the visual aspects but also the melanopic effects and its energy consumption.

Οptimizing colour balance preference and energy efficiency simultaneously is often difficult. Despite advancements in technology enhancing energy efficiency, harmonizing colour preference with energy conservation remains complex. This study investigates the interaction among colour preference, energy efficiency, evaluation frameworks to improve understanding and design practices. Using a methodical approach, research employs multi-criteria decision analysis (MCDA) to optimize colour preference and energy efficiency in lighting design. A computational tool based on genetic algorithms is used to generate nine distinct spectral power distributions (SPDs) with similar Correlated Colour Temperatures (CCT) and average fidelity but varying in gamut shape and size. The Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS), an MCDA method, is then applied to assess colour evaluation systems. TOPSIS compares alternatives based on pre-specified criteria, aiding in the selection of lighting luminaires that balance colour preferences and energy consumption. The study’s findings provide recommendations and expand the discourse on lighting design practices. Future research may explore alternative decision analysis methodologies to refine evaluation frameworks. Harmonizing colour preference with energy efficiency is vital for environmental sustainability and user satisfaction. Strategic methodologies like MCDA and computational tools support the balance of aesthetic preferences and environmental consciousness, promoting sustainable lighting solutions.

We report on the ring-opening polymerization of ɛ-caprolactone incorporated with a magnetic susceptible catalyst, FeCl3, via the use of microwave magnetic heating (HH) which primarily heats the bulk with a magnetic field (H-field) from an electromagnetic field (EMF). Such a process was compared to more commonly used heating methods, such as conventional heating (CH), i.e., oil bath, and microwave electric heating (EH), which is also referred to as microwave heating that primarily heats the bulk with an electric field (E-field). We identified that the catalyst is susceptible to both the E-field and H-field heating, and promoted the heating of the bulk. Which, we noticed such promotion was a lot more significant in the HH heating experiment. Further investigating the impact of such observed effects in the ROP of ɛ-caprolactone, we found that the HH experiments showed a more significant improvement in both the product Mwt and yield as the input power increased. However, when the catalyst concentration was reduced from 400:1 to 1600:1 (Monomer:Catalyst molar ratio), the observed differentiation in the Mwt and yield between the EH and the HH heating methods diminished, which we hypothesized to be due to the limited species available that were susceptible to microwave magnetic heating. But comparable product results between the HH and EH heating methods suggest that the HH heating method along with a magnetic susceptible catalyst could be an alternative solution to overcome the penetration depth problem associated with the EH heating methods. The cytotoxicity of the produced polymer was investigated to identify its potential application as biomaterials.

Colour preference and energy efficiency have long been considered significant characteristics that cannot be maximized simultaneously. Numerous investigations on colour preference and evaluation have been carried out. Sources with larger gamut generally enhance object chroma, which has been found to be preferred by previous studies, however, excessively large gamut may lower preference due to oversaturation. This paper describes a psychophysical experiment for the comparison of the colour preference evaluation among sources of different hue-specific chroma changes and how preference affects energy efficiency. A retail lighting application was created in two side-by-side presentations. A two-metric colour rendering system, consisting of average fidelity and gamut metrics, cannot fully describe colour quality and underscore the importance of a colour rendering graphic. Different spectras with the same correlated colour temperature, average fidelity and average gamut were implemented using an optimized spectral power distributions calculation in order to have systematic variation in gamut shape. Participants of different ages made preference assessments of chromatic objects in a forced-choice protocol, where they evaluated the pairs in a sequential mode. Specific colours strongly influenced participants’ assessments, indicating that gamut shape, additionally to gamut area, is an important component of predicting colour preference and energy efficiency.

A number of pyrrolo[2,3-c]pyridines, pyrrolo[3,2-d]pyrimidines and pyrazolo[4,3-d]pyrimidines were designed and synthesized as antiproliferative agents. The target compounds possessed selected substituents in analogous positions on the central scaffold that allowed the extraction of interesting SARs. The cytotoxic activity of the new derivatives was evaluated against prostatic (PC-3) and colon (HCT116) cell lines, and the most potent analogues showed IC50 values in the nM to low µM range, while they were found to be non-toxic against normal human fibroblasts (WI-38). Flow cytometric analysis of DNA content revealed that the most promising derivative 14b caused a statistically significant accumulation of PC-3 cells at G2/M phase and induced apoptosis in PC-3 cells.

Non-uniform temperature distribution within solid food is a major problem associated with microwave heating, which limits industrial applications. Therefore, an experimentally validated 3D model was proposed to study the effect of microwave applicator geometry on the electromagnetic field distribution and heating pattern of shrimp under different processing conditions. Simulation results were compared with physical experiments, in which a cooked peeled shrimp sample was heated using two different laboratory-scale microwave applicators (rectangular and cylindrical cavities). For the rectangular applicator, the temperature distribution within the shrimp, when examined in cross-section, was more homogeneous compared to that of the cylindrical applicator. The results showed the influence of the complex shape of the food on the temperature distribution during microwave heating, as well as of process parameters (input power and geometry cavity). Moreover, this modelling method could provide a better understanding of the microwave heating process and assist manufacturing companies to evaluate a suitable microwave applicator according to their specific purpose.

IntroductionZika virus (ZIKV) infection during pregnancy is a known cause of microcephaly and other congenital and developmental anomalies. In the absence of a ZIKV vaccine or prophylactics, principal investigators (PIs) and international leaders in ZIKV research have formed the ZIKV Individual Participant Data (IPD) Consortium to identify, collect and synthesise IPD from longitudinal studies of pregnant women that measure ZIKV infection during pregnancy and fetal, infant or child outcomes.Methods and analysisWe will identify eligible studies through the ZIKV IPD Consortium membership and a systematic review and invite study PIs to participate in the IPD meta-analysis (IPD-MA). We will use the combined dataset to estimate the relative and absolute risk of congenital Zika syndrome (CZS), including microcephaly and late symptomatic congenital infections; identify and explore sources of heterogeneity in those estimates and develop and validate a risk prediction model to identify the pregnancies at the highest risk of CZS or adverse developmental outcomes. The variable accuracy of diagnostic assays and differences in exposure and outcome definitions means that included studies will have a higher level of systematic variability, a component of measurement error, than an IPD-MA of studies of an established pathogen. We will use expert testimony, existing internal and external diagnostic accuracy validation studies and laboratory external quality assessments to inform the distribution of measurement error in our models. We will apply both Bayesian and frequentist methods to directly account for these and other sources of uncertainty.Ethics and disseminationThe IPD-MA was deemed exempt from ethical review. We will convene a group of patient advocates to evaluate the ethical implications and utility of the risk stratification tool. Findings from these analyses will be shared via national and international conferences and through publication in open access, peer-reviewed journals.Trial registration numberPROSPERO International prospective register of systematic reviews (CRD42017068915).

Genetic polymorphisms in β1-, β2- and β3-adrenergic receptors (β-ARs) have been associated with chronic non-communicable disorders, such as cardiovascular diseases, asthma, chronic obstructive pulmonary disease (COPD) and obesity, as well as β-agonists and antagonists response and toxicity. The purpose of this study was to determine the frequency distribution of ADRB1 genetic variants Ser49Gly and Arg389Gly, ADRB2 variants Gly16Arg and Gln27Glu, ADRB3 variant Trp64Arg in a Southeastern European Caucasian (SEC) population sample and to establish a comparison with existing data from other human populations. A sample of 431 men and 590 women volunteered to participate in this genotyping analysis after anonymization and de-identification. Real Time PCR (Melting Curve Analysis) followed DNA extraction from buccal swabs and statistical analysis of the results was performed. The allele frequencies in the SEC population were Ser49 (90.3%), Arg389 (69.49%), Gly16 (61.61%), Gln27 (65.72%), and Trp64 (94.52%), while a Hardy-Weinberg Equilibrium (HWE) was detected in the population studied. Comparisons for the Ser49Gly, Gln27Glu, and Trp64Arg allele distributions demonstrated significant differences between SEC and the European group. European subgroups comparisons showed that allele distributions were similar for four of the five SNPs between SEC and Southwestern European Caucasians (SWC), while they were quite distinct from the Northwestern European Caucasians (NWC). These data underline the importance of interethnic variability of β-ARs genetic polymorphisms.

Macromolecules that possess three-dimensional, branched molecular structures are of great interest because they exhibit significantly differentiated application performance compared to conventional linear (straight chain) polymers. This paper reports the synthesis of 3- and 4-arm star branched polymers via ring opening polymerisation (ROP) utilising multi-functional hydroxyl initiators and Sn(Oct)2 as precatalyst. The structures produced include mono-functional hydrophobic and multi-functional amphiphilic core corona stars. The characteristics of the synthetic process were shown to be principally dependent upon the physical/dielectric properties of the initiators used. ROP’s using initiators that were more available to become directly involved with the Sn(Oct)2 in the “in-situ” formation of the true catalytic species were observed to require shorter reaction times. Use of microwave heating (MWH) in homopolymer star synthesis reduced reaction times compared to conventional heating (CH) equivalents, this was attributed to an increased rate of “in-situ” catalyst formation. However, in amphiphilic core corona star formation, the MWH polymerisations exhibited slower propagation rates than CH equivalents. This was attributed to macro-structuring within the reaction medium, which reduced the potential for reaction. It was concluded that CH experiments were less affected by this macro-structuring because it was disrupted by the thermal currents/gradients caused by the conductive/convective heating mechanisms. These gradients are much reduced/absent with MWH because it selectively heats specific species simultaneously throughout the entire volume of the reaction medium. These partitioning problems were overcome by introducing additional quantities of the species that had been determined to selectively heat.

Summary: Mollaret's meningitis is a rare form of benign recurrent aseptic meningitis first described in 1944. We report a case of Mollaret's meningitis due to Herpes Simplex Virus type 2 (HSV2), diagnosed with Polymerase Chain Reaction (PCR) implementation in the Cerebrospinal fluid (CSF) of the patient and treated successfully with acyclovir. To our knowledge, this is the first case of Mollaret's meningitis reported in Greece. We reviewed the literature since PCR has become widely available. Herpes Simplex Virus type 2 has been the most commonly identified causative agent of Mollaret's meningitis. Keywords: Recurrent meningitis, Recurrent benign lymphocytic meningitis, Mollaret's meningitis, Herpes Simplex Virus, Herpetic meningitis