Climatically Accelerated Material Processes Determining the Long-Term Reliability of Light-Emitting Diodes.

LEDs (Light-Emitting Diodes) are widely applied not only in decorative illumination but also in everyday lighting in buildings, flats, public areas, and automotive fields. These application areas often mean harsh environments, for example, regarding the humidity content of the surrounding air: besides outdoor and automotive illumination, even the household use cases (kitchen, bathroom, cellar) may represent extreme temperature and humidity variations (often reaching relative humidity levels close to 100%) for these devices; thus, their reliability behaviour in such circumstances should be better understood. Thermally activated processes were studied in several previous publications, but less information is available regarding high-humidity environmental tests. Moisture and temperature ageing tests with appropriate environmental parameter settings were performed as accelerated lifetime tests to investigate not only the effect of temperature but also that of humidity on the ageing and reliability of LED packages containing RGB (red green blue) chips and phosphor-converted white (pcW) LEDs. The ageing was followed not only through monitoring optical/electrical/spectral parameters but also with material analysis. Moisture-material interaction models were proposed and set up. It was found that humidity-accelerated ageing processes are more severe than expected from previous assumptions. RGB and pcW LEDs showed strongly different behaviour.

Modelling of aerobic granular sludge reactors: the importance of hydrodynamic regimes, selective sludge removal and gradients.

Hydraulic selection is a key feature of aerobic granular sludge (AGS) systems but existing aerobic granular sludge (AGS) models neglect those mechanisms: gradients over reactor height (Hreactor), selective removal of slow settling sludge, etc. This study aimed at evaluating to what extent integration of those additional processes into AGS models is needed, i.e., at demonstrating that model predictions (biomass inventory, microbial activities and effluent quality) are affected by such additional model complexity. We therefore developed a new AGS model that includes key features of full-scale AGS systems: fill-draw operation, selective sludge removal, distinct settling models for flocs/granules. We then compared predictions of our model to those of a fully mixed AGS model. Our results demonstrate that hydraulic selection can be predicted with an assembly of four continuous stirred tank reactors in series together with a correction code for plug-flow. Concentration gradients over the reactor height during settling/plug-flow feeding strongly impact the predictions of aerobic granular sludge models in terms of microbial selection, microbial activities and ultimately effluent quality. Hydraulic selection is a key to predict selection of storing microorganisms (phosphorus-accumulating organisms (PAO) and glycogen-accumulating organisms (GAO)) and in turn effluent quality in terms of total phosphorus, and for predicting effluent solid concentration and dynamic during plug-flow feeding.

Device for Identifying the UV Emission Spectrum.

Nowadays, the disinfection of classrooms, shopping malls, and offices has become an important part of our lives. One of the most effective disinfection methods is ultraviolet (UV) radiation. To ensure the disinfection device has the required wavelength spectrum, we need to measure it with dedicated equipment. Thus, in this work, we present the development of a UV spectrum detector capable of identifying UV wavelength spectrums, with a wide range of probes and the ability to transmit data to a PC for later evaluation of the results. The device was developed with four UV sensors: one for UV-A, one for UV-B, one for UV-C, and one with a wide range of detection of UVA, with a built-in transimpedance amplifier. An Arduino Nano development board processes all the acquired data. We developed a custom light source containing seven UV LEDs with different central wavelengths to calibrate the device. For easy visualization of the results, custom PC software was developed in the Processing programming medium. For the two pieces of electronics-the UV detector and calibration device-3D-printed housings were created to be ergonomic for the end-user. From the price point of view, this device is affordable compared to what we can find on the market.

Design and Control of Perylene Supramolecular Polymers through Imide Substitutions.

The number and type of new supramolecular polymer (SMP) systems have increased rapidly in recent years. Some of the key challenges faced for these novel systems include gaining full control over the mode of self-assembly, the creation of novel architectures and exploring functionality. Here, we provide a critical overview of approaches related to perylene-based SMPs and discuss progress to exert control over these potentially important SMPs through chemical modification of the imide substituents. Imide substitutions affect self-assembly behaviour orthogonally to the intrinsic optoelectronic properties of the perylene core, making for a valuable approach to tune SMP properties. Several recent approaches are therefore highlighted, with a focus on controlling 1) morphology, 2) H- or J- aggregation, and 3) mechanism of growth and degree of aggregation using thermodynamic and kinetic control. Areas of potential future exploration and application of these functional SMPs are also explored.

Facebook Users' Interactions, Organic Reach, and Engagement in a Smoking Cessation Intervention: Content Analysis.

BACKGROUND: Facebook can be a suitable platform for public health interventions. Facebook users can express their reaction to the given social media content in many ways using interaction buttons. The analysis of these interactions can be advantageous in increasing reach and engagement of public health interventions. OBJECTIVE: This research aimed at understanding how Facebook users' interactions correlate with organic reach and engagement regarding the same smoking cessation support contents. METHODS: The study population consisted of Facebook users who were reached by a public smoking cessation support page without advertising. We included 1025 nonpaid Facebook posts (N=1025) which used smoking cessation strategies based on a motivational interviewing counseling style. The following data were collected from the "Post Details": the number of people who saw the given nonpaid content (organic reach) which consisted of fan and nonfan reach according to previous "page like" activity; each rate of "engagement indicators" (such as the symbols of "like," "love," "haha," "wow," "sad," "angry"; or other interactions: "shares," "comments," "clicks"); and the rate of negative Facebook interactions (eg, "post hides" or "unlike of page"). Overall, these data were analyzed with the Spearman correlation method. RESULTS: Surprisingly, we found a significant negative correlation between organic reach and the "like" reaction (rs=-0.418; P<.001). The strongest significant positive correlations of organic reach were observed with the "haha" reaction (rs=0.396; P<.001), comments (rs=0.368; P<.001), and the "love" reaction (rs=0.264; P<.001). Furthermore, nonfan reach correlated positively with "shares" (rs=0.388; P<.001) and clicks (rs=0.135; P<.001), while fan reach correlated positively with the "haha" reaction (rs=0.457; P<.001), comments (rs=0.393; P<.001), and the "love" reaction (rs=0.310; P<.001). Contrary to expectations, the "like" reaction was sharply separated by significant negative correlations from "wow" (rs=-0.077; P=.013), "sad" (rs=-0.120; P<.001), "angry" reactions (rs=-0.136; P<.001), and comments (rs=-0.130; P<.001). Additionally, a high rate of negative Facebook interactions was significantly associated with "wow" (rs=0.076; P=.016) and "sad" reactions (rs=0.091; P=.003). CONCLUSIONS: This study has shown that it is possible to hypothesize a disadvantage of the "like" reaction and advantages of other interactions (eg, the "haha" reaction or "comments") in content algorithmic ranking on Facebook. In addition, the correlational analysis revealed a need of a further categorization to fan-specific interactions (eg, "haha" or "love" reactions) and nonfan-specific interactions (eg, "shares" and "clicks"). Regarding the direction of the correlations, these findings suggest that some interactions (eg, negative Facebook interactions, "wow," "sad," and "angry" reactions) may decrease the engagement, while other interactions ("like," "love," "haha" reactions, "shares," and "clicks") may increase the engagement during Facebook-based smoking cessation interventions. This hypothesis-generating research offers an important insight into the relationship between organic reach, engagement, and Facebook users' interactions for public health professionals who design Facebook-based interventions.

Deregulation of whole-transcriptome gene expression in zebrafish (Danio rerio) after chronic exposure to low doses of imatinib mesylate in a complete life cycle study.

Imatinib mesylate (IM) is an anticancer drug that belongs to tyrosine kinase inhibitors. We report the results of the first investigation of the chronic exposure of zebrafish (Danio rerio) to IM. The exposure to IM (0.01, 1 and 100 µg/L) was initiated in adult fish and continued through hatching and the offspring generation for seven months. In addition to standard toxicological endpoints, induction of genotoxic effects and whole-genome transcriptome of liver samples of offspring generation of zebrafish were analysed. Exposure to IM did not affect the survival and growth of zebrafish, did not cause any histopathological changes, but it induced a marginal increase in the chromosomal damage in blood cells. The whole-genome transcriptome analyses demonstrated dose-dependent increase in the number of differentially expressed genes with a significantly higher number of deregulated genes in female fish compared to male. Differentially expressed genes included genes involved in response to DNA damage, cell cycle control and regulation of circadian rhythm. Based on the low genotoxic activity and the pattern of the changes in DNA damage responsive genes we consider that at current environmental exposure levels, IM represents low risk for genotoxic effects in aquatic organisms. Exposure to IM also induced deregulation of the expression of genes associated with steroidogenesis and hormone metabolism and function, which indicates hormone-disrupting activity of IM that has not been studied so far. The study provide new information on the potential consequences of chronic exposure to the residues of tyrosine kinase inhibitors, which remain to be further explored.

Thermodynamical Extension of a Symplectic Numerical Scheme with Half Space and Time Shifts Demonstrated on Rheological Waves in Solids.

On the example of the Poynting-Thomson-Zener rheological model for solids, which exhibits both dissipation and wave propagation, with nonlinear dispersion relation, we introduce and investigate a finite difference numerical scheme. Our goal is to demonstrate its properties and to ease the computations in later applications for continuum thermodynamical problems. The key element is the positioning of the discretized quantities with shifts by half space and time steps with respect to each other. The arrangement is chosen according to the spacetime properties of the quantities and of the equations governing them. Numerical stability, dissipative error, and dispersive error are analyzed in detail. With the best settings found, the scheme is capable of making precise and fast predictions. Finally, the proposed scheme is compared to a commercial finite element software, COMSOL, which demonstrates essential differences even on the simplest-elastic-level of modeling.

Ballistic-Diffusive Model for Heat Transport in Superlattices and the Minimum Effective Heat Conductivity.

There has been much interest in semiconductor superlattices because of their low thermal conductivities. This makes them especially suitable for applications in a variety of devices for the thermoelectric generation of energy, heat control at the nanometric length scale, etc. Recent experiments have confirmed that the effective thermal conductivity of superlattices at room temperature have a minimum for very short periods (in the order of nanometers) as some kinetic calculations had anticipated previously. This work will show advances on a thermodynamic theory of heat transport in nanometric 1D multilayer systems by considering the separation of ballistic and diffusive heat fluxes, which are both described by Guyer-Krumhansl constitutive equations. The dispersion relations, as derived from the ballistic and diffusive heat transport equations, are used to derive an effective heat conductivity of the superlattice and to explain the minimum of the effective thermal conductivity.

Entropy and Non-Equilibrium Statistical Mechanics.

The present Special Issue, 'Entropy and Non-Equilibrium Statistical Mechanics', consists of seven original research papers [...].

Four Spacetime Dimensional Simulation of Rheological Waves in Solids and the Merits of Thermodynamics.

The recent results attained from a thermodynamically conceived numerical scheme applied on wave propagation in viscoelastic/rheological solids are generalized here, both in the sense that the scheme is extended to four spacetime dimensions and in the aspect of the virtues of a thermodynamical approach. Regarding the scheme, the arrangement of which quantity is represented where in discretized spacetime, including the question of appropriately realizing the boundary conditions, is nontrivial. In parallel, placing the problem in the thermodynamical framework proves to be beneficial in regards to monitoring and controlling numerical artefacts-instability, dissipation error, and dispersion error. This, in addition to the observed preciseness, speed, and resource-friendliness, makes the thermodynamically extended symplectic approach that is presented here advantageous above commercial finite element software solutions.

Correction to: National dose reference levels in computed tomography-guided interventional procedures-a proposal.

The original version of this article, published on 02 May 2020, unfortunately contained a mistake.

National dose reference levels in computed tomography-guided interventional procedures-a proposal.

OBJECTIVES: To establish national reference levels (RLs) in interventional procedures under CT guidance as required by the 2013/59/Euratom European Directive. METHODS: Seventeen categories of interventional procedures in thoracic, abdominopelvic, and osteoarticular specialties (percutaneous infiltration, vertebroplasty, biopsy, drainage, tumor destruction) were analyzed. Total dose length product (DLP), number of helical acquisitions (NH), and total DLP for helical, sequential, or fluoroscopic acquisitions were recorded for 10 to 20 patients per procedure at each center. RLs were calculated as the 3rd quartiles of the distributions and target values for optimization process (TVOs) as the median. RLs and TVOs were compared with previously published studies. RESULTS: Results on 5001 procedures from 49 centers confirmed the great variability in patient dose for the same category of procedures. RLs were proposed for the DLPs and NHs in the seventeen categories. RLs in terms of DLP and NH were 375 mGy.cm and 2 NH for spinal or peri-spinal infiltration, 1630 mGy.cm and 3 NH for vertebroplasty, 845 mGy.cm and 4 NH for biopsy, 1950 mGy.cm and 8 NH for destruction of tumors, and 1090 mGy.cm and 5 NH for drainage. DLP and NH increased with the complexity of procedures. CONCLUSIONS: This study was the first nationwide multicentric survey to propose RLs for interventional procedures under CT guidance. Heterogeneity of practice in centers were found with different levels of patient doses for the same procedure. The proposed RLs will allow imaging departments to benchmark their practice with others and optimize their protocols. KEY POINTS: • National reference levels are proposed for 17 categories of interventional procedures under CT guidance. • Reference levels are useful for benchmarking practices and optimizing protocols. • Reference levels are proposed for dose length product and the number of helical acquisitions.

Acute Cerebral Stroke with Multiple Infarctions and COVID-19, France, 2020.

We describe 2 cases in coronavirus disease patients in France involving presumed thrombotic stroke that occurred during ongoing anticoagulation treatment for atrial fibrillation stroke prophylaxis; 1 patient had positive antiphospholipid antibodies. These cases highlight the severe and unique consequences of coronavirus disease-associated stroke.

[Tobacco reduction on Facebook among 14-35-year-olds]. / A dohányzás visszaszorítása a Facebook segítségével a 14­35 éves korosztály körében.

INTRODUCTION: The possibility of successful smoking cessation is increased by early initiation. Therefore, promoting smoking cessation at early age (especially among 14-35-year-olds) has a key role in reducing tobacco use prevalence. Facebook is one of the most popular websites among adolescents and young adults which can be used for age-specific smoking cessation support. AIM: Our research seeks to reveal the effects of a Facebook page on smoking habits, smoking cessation knowledge and attitudes among 14-35-year-olds. METHOD: An online survey was conducted among the 3278 followers of the author's Facebook page. The questionnaire was completed by 332 people among 14-35-year-olds. We analysed demographic data, smoking habits, the usage frequency and duration of the Facebook page as well as changes in smoking habits, smoking cessation knowledge and attitudes. RESULTS: The average age was 22.57 ± 5.08 years. The examined population consisted of 65% currently smokers, 12% former smokers and 23% non-smokers. Significantly more people reported a positive change in their smoking habits and smoking cessation attitudes among smokers who used the Facebook page more frequently and with longer duration (p<0.05). The habit and attitude changes were significantly higher among smokers who plan to quit smoking (p<0.01). Nevertheless, we also observed attitude changes between 12-25% among smokers who did not plan to quit. Among non-smokers, the positive attitude changes were significantly higher in the low-educated population who live in villages (p<0.01). CONCLUSION: This Facebook page had a positive effect on smoking habits, smoking cessation knowledge and attitudes among 14-35-year-olds. The contents of the Facebook page could be used to prevent smoking and support smoking cessation among 14-35-year-olds. Orv Hetil. 2019; 160(6): 220-227.

Estrogen sensitive liver transgenic zebrafish (Danio rerio) line (Tg(vtg1:mCherry)) suitable for the direct detection of estrogenicity in environmental samples.

Environmental estrogens are a serious concern worldwide due to their ubiquity and adverse ecotoxicological and health effects. Chemical structure of these substances is highly diverse, therefore estrogenicity cannot be predicted on the basis of molecular structure. Furthermore, estimation of estrogenicity of environmental samples based on chemical analytics of suspects is difficult given the complex interaction of chemicals and the impact on estrogenicity. The full estrogenic impact of an environmental sample can thus only be revealed by a series of sensitive in vitro and in vivo ecotoxicological tests. Herein we describe a vitellogenin reporter transgenic zebrafish line (Tg(vtg1:mCherry)) that enables the detection of estrogenicity in the environmentally relevant, low concentration ranges in embryonic tests that are in accordance with 3Rs and relevant animal welfare regulations. The transgene construct used for the development of Tg(vtg1:mCherry) carried a long (3.4 kbp) natural vitellogenin-1 promoter sequence with a high number of ERE sites. A test protocol was developed based on our finding that the endogenous vitellogenin and the reporter show similar spatial expression pattern and both endogenous and vitellogenin reporter is only produced in the left hepatic lobe of 5 dpf zebrafish embryos. Seven generations of Tg(vtg1:mCherry) have been established, and the estrogen responsiveness was tested with different estrogenic substances and wastewater samples. Embryos were exposed from 3 to 5 days post fertilization (dpf). Fluorescence in embryos could be detected upon treatment with 17-ß-estradiol from a concentration of 100 ng/L, 17-α-ethynilestradiol from 1 ng/L, zearalenone from 100 ng/L and bisphenol-A from 1 mg/L. In the adult stage transgene activity appeared to be more sensitive to estrogen treatment, with detectable transgene activity from 5 ng/L 17-ß-estradiol concentration. The transgenic line Tg(vtg1:mCherry) was also suitable for the direct measurement of estrogenicity in wastewater samples without sample extraction. The detection of estrogenic activity using the reporter line was confirmed by the bioluminescent yeast estrogen screen.

On the Rarefied Gas Experiments.

There are limits of validity of classical constitutive laws such as Fourier and Navier-Stokes equations. Phenomena beyond those limits have been experimentally found many decades ago. However, it is still not clear what theory would be appropriate to model different non-classical phenomena under different conditions considering either the low-temperature or composite material structure. In this paper, a modeling problem of rarefied gases is addressed. The discussion covers the mass density dependence of material parameters, the scaling properties of different theories and aspects of how to model an experiment. In the following, two frameworks and their properties are presented. One of them is the kinetic theory based Rational Extended Thermodynamics; the other one is the non-equilibrium thermodynamics with internal variables and current multipliers. In order to compare these theories, an experiment on sound speed in rarefied gases at high frequencies, performed by Rhodes, is analyzed in detail. It is shown that the density dependence of material parameters could have a severe impact on modeling capabilities and influences the scaling properties.

Emergence of Non-Fourier Hierarchies.

The non-Fourier heat conduction phenomenon on room temperature is analyzed from various aspects. The first one shows its experimental side, in what form it occurs, and how we treated it. It is demonstrated that the Guyer-Krumhansl equation can be the next appropriate extension of Fourier's law for room-temperature phenomena in modeling of heterogeneous materials. The second approach provides an interpretation of generalized heat conduction equations using a simple thermo-mechanical background. Here, Fourier heat conduction is coupled to elasticity via thermal expansion, resulting in a particular generalized heat equation for the temperature field. Both aforementioned approaches show the size dependency of non-Fourier heat conduction. Finally, a third approach is presented, called pseudo-temperature modeling. It is shown that non-Fourier temperature history can be produced by mixing different solutions of Fourier's law. That kind of explanation indicates the interpretation of underlying heat conduction mechanics behind non-Fourier phenomena.

Biofilm carrier migration model describes reactor performance.

The accuracy of a biofilm reactor model depends on the extent to which physical system conditions (particularly bulk-liquid hydrodynamics and their influence on biofilm dynamics) deviate from the ideal conditions upon which the model is based. It follows that an improved capacity to model a biofilm reactor does not necessarily rely on an improved biofilm model, but does rely on an improved mathematical description of the biofilm reactor and its components. Existing biofilm reactor models typically include a one-dimensional biofilm model, a process (biokinetic and stoichiometric) model, and a continuous flow stirred tank reactor (CFSTR) mass balance that [when organizing CFSTRs in series] creates a pseudo two-dimensional (2-D) model of bulk-liquid hydrodynamics approaching plug flow. In such a biofilm reactor model, the user-defined biofilm area is specified for each CFSTR; thereby, Xcarrier does not exit the boundaries of the CFSTR to which they are assigned or exchange boundaries with other CFSTRs in the series. The error introduced by this pseudo 2-D biofilm reactor modeling approach may adversely affect model results and limit model-user capacity to accurately calibrate a model. This paper presents a new sub-model that describes the migration of Xcarrier and associated biofilms, and evaluates the impact that Xcarrier migration and axial dispersion has on simulated system performance. Relevance of the new biofilm reactor model to engineering situations is discussed by applying it to known biofilm reactor types and operational conditions.

l-Alpha Glycerylphosphorylcholine as a Potential Radioprotective Agent in Zebrafish Embryo Model.

This work establishes the zebrafish embryo model for ionizing radiation (IR) modifier research and also evaluates the protective effect of l-alpha glycerylphosphorylcholine (GPC). Embryos were exposed to a single-fraction whole-body gamma irradiation (5, 10, 15, and 20 Gy) at different postfertilization time points and were serially assessed for viability and macro- and micromorphologic abnormalities. After toxicity evaluation, 194 µM of GPC was added for certain groups with 3-h incubation before the radiation. Nuclear factor kappa B (NF-κB) and interleukin-1ß (IL-1ß) expression changes were measured using quantitative real-time polymerase chain reaction. A higher sensitivity could be observed at earlier stages of the embryogenesis. The lethal dose (LD50) for 6 hours postfertilization (hpf) embryos was 15 Gy and for 24 hpf was 20 Gy on day 7, respectively. GPC administration resulted in a significant improvement in both the distortion rate and survival of the 24 hpf embryos. Qualitative evaluation of the histological changes confirmed the protective effect of GPC. IL-1ß and NF-κB overexpression due to 10 Gy irradiation was also reduced by GPC. GPC exhibited promising radioprotective effects in our zebrafish embryo model, decreasing the irradiation-induced morphological damage and lethality with significant reduction of IR-caused pro-inflammatory activation.

Hormonal activity, cytotoxicity and developmental toxicity of UV filters.

Ultraviolet (UV) filters are commonly used compounds in personal care products and polymer based materials, as they can absorb solar energy in the UVA and UVB spectrum. However, they are able to bind to hormone receptors and have several and different types of hormonal activities determined by in vitro assays. One of the aims of this work was to measure the hormonal and cytotoxic activities of four frequently used UV filters using bioluminescence based yeast test organisms. Using Saccharomyces cerevisiae BLYES and BLYAS strains allowed the rapid and reliable detection of agonist and antagonist hormonal activities, whereas BLYR strain served to measure cytotoxicity. Results confirmed that all tested UV filters show multiple hormonal activities. Cytotoxicity is detected only in the case of benzophenone-3. Research data on the toxic effects of benzophenone-3, especially on aquatic organisms are scarce, so further investigations were carried out regarding its cytotoxic and teratogenic effects on bacteria and zebrafish (Danio rerio) embryos, respectively. Results revealed the cytotoxicity of benzophenone-3 not only to yeasts but to bacteria, as well as its ability to influence zebrafish embryo hatching and development.