A Simple Method for the Detection of Biofilms Using a Heatable Capacitive Sensor Structure (CSS): Description, Proof of Concept, and Some Technical Improvements

This article presents a novel method for the detection of biofilms based on a heatable, capacitive sensor structure (CSS). Biofilms are capable of strongly binding large amounts of water to their extracellular biopolymer matrix, which is detectable via its dielectric properties. A main challenge is to determine the difference between the inherent occurring presence of moisture in the ecosystem, which is necessary to form a biofilm and an actual formed biofilm. Therefore, the CSS is carefully heated to evaporate unbound surface moisture and determine whether there is a remaining residual alternation of the capacitance in comparison to the dry state. As a reproduceable substitute for complex, real biofilms, a hygroscopic, medical hydrogel-based on polysaccharides was used and applied by spray coating. Printed circuit boards (PCB) in different geometries and materials were used as CSS and compared in terms of their performance. A layer-thickness of 20 µm for the hydrogel coating to be sufficiently detected was defined as a realistic condition based on known values for real biofilms cited in literature. For this thickness a double-meander structure proves to be preferable over interdigitating and spiral geometries. It does offer a 30% lower, yet sufficient sensitivity, but shows advantages in manufacturing (one layer instead of two) and conductive heating capability. In the experiments, free water showed virtually no residual change, while the hydrogel-coated CSS still shows an approx. 300% higher value compared to a dry capacity. Yet, the overall small capacities of about 6–30 pF in dry state are difficult to measure and therefore sensitive to interferences and noise, which results in a high deviation. The principle of measurement can be evaluated as proofed by the carried out experiments, though offering room for improvement in the design of the study. The new method might be especially useful for pipes (e.g., hydrodynamically ineffective sensors installed in a pipe wall) if they at least are not permanently flooded with an aqueous medium, but can occasionally dry. If the internal surface is still only moist, it can be dried by initial heating.

Ghost lineages invalidate or reverse several results on gene flow

Introgression, endosymbiosis and gene transfer, i.e. Horizontal Gene Flow (HGF), are primordial sources of innovation in all domains of life. Our knowledge on HGF relies on detection methods that exploit some of its signatures left on extant genomes. One of them is the effect of HGF on branch lengths of constructed phylogenies. This signature has been formalized in statistical tests for HGF detection, and used for example to detect massive adaptive gene flows in malaria vectors or to order evolutionary events involved in eukaryogenesis. However these studies rely on the assumption that ghost lineages (all unsampled extant and extinct taxa) have little influence. We demonstrate here with simulations and data re-analysis, that when considering the more realistic condition that unsampled taxa are legion compared to sampled ones, the conclusion of these studies become unfounded or even reversed. This illustrates the necessity to recognize the existence of ghosts in evolutionary studies.

Seizure Prediction With HIVE-CODAs: The Hierarchical Vote Collective of Domain Adaptation Methods

Epileptic seizure prediction is one of the most used therapeutic adjuvant strategies for drug-resistant epilepsy. Conventional methods are usually trained and tested on the same patient due to the interindividual variability. However, the challenging problem of the domain shift between different subjects remains unsolved, resulting in low prevalence of clinical application. In this study, a generic model based on the domain adaptation (DA) technique is proposed to alleviate such problems. Ensemble learning is employed by developing a hierarchical vote collective of seven DA modules over multi-modality data, such that the predictive performance is improved by training multiple models. Moreover, to increase the feasibility of its implementation, this study mimics the data distribution of clinical sampling and tests the model under this simulated realistic condition. Based on the performance of seven subnetworks, the applicability of each DA algorithm for seizure prediction is evaluated, which is the first study that provides the assessment. Experimental results on both intracranial and scalp EEG databases demonstrate that this method can reduce the domain gap effectively compared with previous studies.

Influences of Zero Mass Flux and Active Conditions on the Predictions of Double Dispersion and Double Diffusive Boundary Layer in Darcy/Non Darcy Nanofluid Flow

Free convective of nanofluid inside dispersive porous medium adjacent to a vertical plate under the effects of the zero mass nanoparticles flux condition and the thermal and solutal dispersions is studied. Buongiorno's model revised is used considering Darcy and non Darcy laminar flows, and isothermal or convective flux outer the wall. Dimensionless governing equations formulated using velocity, temperature, concentration and nanoparticle volume fraction have been solved by finite difference method that implements the 3-stage Lobatto collocation formula. The numerical data obtained with semi or full dispersions cases are compared to predictions made using the non dispersive porous medium. Taking into account the dispersions, the influence of the zero mass nanoparticles flux condition is examined to test the validity of the control active nanoparticle assumption. It is found mainly that the thermal transfers can reach more than 100% in connection with the case where of a semi-dispersion of the porous medium is applied. Realistic condition, i.e. zero mass flux should be addressed for the heat transfer rate rather than the mass transfer rate, discovered markedly different to the active condition. This signifies the importance of considering the zero nanoparticles mass flux and dispersions in the performance characterization of nanofluid flow in porous media.

The Effect of Fantasy Context on Moral Action and Judgment

Research suggests individuals import real-world facts into fictional worlds based on the type of fact and fictional context. We examined the importation of real-world morality across fictional contexts. Undergraduate (Study 1) and MTurk (Study 2) participants were randomly assigned to read either a realistic or matching fantastical interactive narrative. At seven junctions, participants were presented with a choice between behaving morally and behaving immorally to advance their goals. In Study 3, an MTurk sample judged the actions of a character who behaved immorally. For Study 1, a gender by condition interaction was found, with males electing more immoral actions in the fantasy condition. For Study 2, no such effect was found. Nonetheless, in Study 3, participants judged immoral actions in the realistic condition as more immoral compared to the fantasy context. Across all studies, transportation predicted choosing fewer immoral actions and judging immoral actions more harshly.

The Plausibility Paradox for Resized Users in Virtual Environments

This paper identifies and confirms a perceptual phenomenon: when users interact with simulated objects in a virtual environment where the users’ scale deviates greatly from normal, there is a mismatch between the object physics they consider realistic and the object physics that would be correct at that scale. We report the findings of two studies investigating the relationship between perceived realism and a physically accurate approximation of reality in a virtual reality experience in which the user has been scaled by a factor of ten. Study 1 investigated perception of physics when scaled-down by a factor of ten, whereas Study 2 focused on enlargement by a similar amount. Studies were carried out as within-subjects experiments in which a total of 84 subjects performed simple interaction tasks with objects under two different physics simulation conditions. In the true physics condition, the objects, when dropped and thrown, behaved accurately according to the physics that would be correct at that either reduced or enlarged scale in the real world. In the movie physics condition, the objects behaved in a similar manner as they would if no scaling of the user had occurred. We found that a significant majority of the users considered the movie physics condition to be the more realistic one. However, at enlarged scale, many users considered true physics to match their expectations even if they ultimately believed movie physics to be the realistic condition. We argue that our findings have implications for many virtual reality and telepresence applications involving operation with simulated or physical objects in abnormal and especially small scales.

The Impact of Climate Change on Hydro-meteorological Droughts Using Copula Functions

Climate change has made many alterations to the Earth's climate, including hydro-climatic extreme events. For investigating the effect of climate change on hydro-meteorological droughts in the Kamal-Saleh dam basin in Markazi province, Iran, a new and comprehensive index was developed for accurate estimation of drought in a more realistic condition, for future climate conditions. This aggregate drought index (ADI) represents the main characteristics of meteorological and hydrological drought. Temperature and precipitation projections for future climates were simulated by five CMIP5 models and downscaled over the study area for the periods of 2050s (2040-2069) and 2080s (2070-2099) relative to the baseline period (1976-2005). By fitting five univariate distribution functions on drought severity and duration, proper marginal distributions were selected. The joint distribution of drought severity and duration was chosen from five types of copula functions. The results revealed that severe droughts are expected to occur frequently in a shorter period in the future.

Numerical simulation and experimental study of blade pitch effect on Darrieus straight-bladed wind turbine with high solidity

Increasing the solidity in vertical axis wind turbines (VAWT) leads to the decreased coefficient of performance (COP) despite the improved start-up performance. To overcome this problem, the pitch regulation system is proposed in this paper for increasing the solidity. In most of the previous investigations, the effect of pitch angle was tested on low-solidity VAWT at uniform flow conditions and low turbulence intensity in wind tunnel test sections, which are different from the real conditions. In this investigation, the influence of pitch angle on the aerodynamic performance of a small Darrieus-type straight-bladed high-solidity VAWT equipped with a pitch regulation system is investigated numerically and experimentally under realistic condition. The proposed numerical procedure is validated through experimental test results. The COP is measured and calculated at different tip speed ratios and two pitch angles of 0 and 5°. The results reveal 25% enhancement in maximum COP with the increase of pitch angle up to 5°. Moreover, according to the numerical results, higher accuracy can be obtained at lower tip speed ratios for both pitch angles. Then, the numerical method is employed to calculate the power (performance) and torque coefficients as a function of Azimuth position as well as the flow field in rotor affected zone and lateral distance. It is found that increasing the pitch angle at a constant tip speed ratio is followed by accelerated vorticity generation, occurrence of maximum COP at lower tip speed ratio and smoother velocity profile in lateral distances of the rotor.

Dynamic modeling of the heat transfer process in rotary kilns with indirect oil heating: Parametric analysis of gypsum calcination case

This work proposes a mathematical modeling and numerical simulation of a gypsum rotary kiln with indirect oil heating in a three-dimensional transient regime. The mathematical model was based on Fourier's Law as a constitutive relationship and the principle of energy conservation, applied to a control volume in cylindrical coordinates. Furthermore, a bed homogenization model was used to represent the most realistic condition of the physical phenomenon since some rotary kilns have internal fins that aim at homogenizing the gypsum temperature during calcination. This work intends to fill the gap found in heat transfer processes on rotary kilns in transient regime considering three dimensions positions, to have an accurate projection of the temperature profile of the kiln and also, given by the numerical model, the possibility of a tool that can be used to the optimization of the control system of rotary kilns considering the actual demand of the material in production, leading to the best energy performance of the equipment's activation source, as well as reaching the temperatures and processing time of the product. The numerical simulation results revealed reasonable agreement with the experimentally determined calcination process in rotary kilns. Furthermore, a parametric analysis of the influence of the mixture on the temperature fields and the calcination time was carried out to verify the energetic balance of the rotary kiln.

Theoretical insights of codoping to modulate electronic structure of $$\hbox {TiO}_2$$ and $$\hbox {SrTiO}_3$$ for enhanced photocatalytic efficiency

$$\hbox {TiO}_2$$ TiO 2 and $$\hbox {SrTiO}_3$$ SrTiO 3 are well known materials in the field of photocatalysis due to their exceptional electronic structure, high chemical stability, non-toxicity and low cost. However, owing to the wide band gap, these can be utilized only in the UV region. Thus, it’s necessary to expand their optical response in visible region by reducing their band gap through doping with metals, nonmetals or the combination of different elements, while retaining intact the photocatalytic efficiency. We report here, the codoping of a metal and a nonmetal in anatase $$\hbox {TiO}_2$$ TiO 2 and $$\hbox {SrTiO}_3$$ SrTiO 3 for efficient photocatalytic water splitting using hybrid density functional theory and ab initio atomistic thermodynamics. The latter ensures to capture the environmental effect to understand thermodynamic stability of the charged defects at a realistic condition. We have observed that the charged defects are stable in addition to neutral defects in anatase $$\hbox {TiO}_2$$ TiO 2 and the codopants act as donor as well as acceptor depending on the nature of doping (p-type or n-type). However, the most stable codopants in $$\hbox {SrTiO}_3$$ SrTiO 3 mostly act as donor. Our results reveal that despite the response in visible light region, the codoping in $$\hbox {TiO}_2$$ TiO 2 and $$\hbox {SrTiO}_3$$ SrTiO 3 cannot always enhance the photocatalytic activity due to either the formation of recombination centers or the large shift in the conduction band minimum or valence band maximum. Amongst various metal-nonmetal combinations, $$\hbox {Mn}_\text {Ti}\hbox {S}_\text {O}$$ Mn Ti S O (i.e. Mn is substituted at Ti site and S is substituted at O site), $$\hbox {S}_\text {O}$$ S O in anatase $$\hbox {TiO}_2$$ TiO 2 and $$\hbox {Mn}_\text {Ti}\hbox {S}_\text {O}$$ Mn Ti S O , $$\hbox {Mn}_\text {Sr}\hbox {N}_\text {O}$$ Mn Sr N O in $$\hbox {SrTiO}_3$$ SrTiO 3 are the most potent candidates to enhance the photocatalytic efficiency of anatase $$\hbox {TiO}_2$$ TiO 2 and $$\hbox {SrTiO}_3$$ SrTiO 3 under visible light irradiation.