This paper reports on the first hologram in transmission mode based on a c-Si metasurface in the visible range. The hologram shows high fidelity and high efficiency, with measured transmission and ...diffraction efficiencies of ~65% and ~40%, respectively. Although originally designed to achieve full phase control in the range 0-2π at 532 nm, these holograms have also performed well at 444.9 nm and 635 nm. The high tolerance to both fabrication and wavelength variations demonstrate that holograms based on c-Si metasurfaces are quite attractive for diffractive optics applications, and particularly for full-color holograms.
Growing environmental concerns and the demand for sustainable resource use have raised questions about the conventional use of lithium-ion batteries. In this context, solid-state sodium-based ...batteries are considered promising energy storage devices due to their excellent performance, cost-effectiveness, and eco-friendly composition. Despite their unquestionable storage capacity, this new battery type may possess additional functionalities that have not been thoroughly explored in the existing literature. In this study, the application of a novel battery developed by a research group at the University of Porto as a strain-sensing device under vibration loads is demonstrated. This battery is an all-solid-state sodium-ion-based ferroelectric battery, and it is expected to exhibit piezoelectric behaviour. With the goal of potential future applications in self-powered Structural Health Monitoring (SHM) systems, the experimental setup replicates conditions similar to those encountered in damage monitoring of composite structures. The solid-state battery is attached to an aluminium beam, which is clamped to an electrodynamic shaker. The beam-battery system is then subjected to constant-frequency excitation, and the battery’s electric potential output is analysed in both time and frequency domains. The filtering of the acquired signal from the battery significantly reduced both the interference and harmonic distortion. The experimental results for the base excitation of 25Hz showed a dominance of the unfiltered 60Hz interference of +14 dB in relation to the unfiltered vibrational signal, while in the filtered situation the amplitude of the vibrational signal was +33 dB above the interference. The same tendency is observed under different frequency excitations. The results indicate that the battery generates a potential difference at the same frequency as that imposed by the shaker. However, its low sensitivity and susceptibility to electromagnetic noise from the electric grid limits the maximum frequency it can effectively monitor. Based on the positive results obtained in the present study, the authors believe that such a device opens up new possibilities for various applications of solid-state batteries, combining their energy storage capabilities with smart sensing functionalities.
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•Dynamic tests on a novel battery.•Demonstration of the battery’s strain-sensing capabilities under vibration loads.•Potential applications to self-powered SHM systems.
Further characterization of genetic structural variations should strongly focus on small and endangered local breeds given their role in unraveling genes and structural variants underlying selective ...pressures and phenotype variation. A comprehensive genome‐wide assessment of copy number variations (CNVs) based on whole‐genome re‐sequencing data was performed on three Brazilian locally adapted cattle breeds (Caracu Caldeano, Crioulo Lageano, and Pantaneiro) using the ARS‐UCD1.2 genome assembly. Data from 36 individuals with an average coverage depth of 14.07× per individual was used. A total of 24 945 CNVs were identified distributed among the breeds (Caracu Caldeano = 7285, Crioulo Lageano = 7297, and Pantaneiro = 10 363). Deletion events were 1.75–2.07‐fold higher than duplications, and the total length of CNVs is composed mostly of a high number of segments between 10 and 30 kb. CNV regions (CNVRs) are not uniformly scattered throughout the genomes (n = 463), and 105 CNVRs were found overlapping among the studied breeds. Functional annotation of the CNVRs revealed variants with high consequence on protein sequence harboring relevant genes, in which we highlighted the BOLA‐DQB, BOLA‐DQA5, CD1A, β‐defensins, PRG3, and ULBP21 genes. Enrichment analysis based on the gene list retrieved from the CNVRs disclosed over‐represented terms (p < 0.01) strongly associated with immunity and cattle resilience to harsh environments. Additionally, QTL associated with body conformation and dairy‐related traits were also unveiled within the CNVRs. These results provide better understanding of the selective forces shaping the genome of such cattle breeds and identify traces of natural selection pressures by which these populations have been exposed to challenging environmental conditions.
The design of solid-state materials whose properties and functions can be manipulated in a controlled manner by the application of electron beam irradiation is important in modern materials chemistry ...and physics. In this paper, we present a progress in the development of scalable electron beam irradiation platform to obtain innovative materials for technological and industrial applications, since one of the problems to be solved in this research area is the scalability of these new nanomaterials induced by electron beam irradiation (EBI). In particular, we focus on carbon structures due to its excellent and exciting properties applied in the technological area in the last years, where we show for the first time a new strategy for carbon allotropic transformation through the portable EBI. This new platform is particularly effective, fast, versatile, clean and easy-to-use, facilitating the preparation of many types of nanomaterials that cannot be obtained by conventional chemical and physical methods. The EBI on flat graphite pellets resulted in a covering of it surface with rod-like particles composed of different allotropic forms of carbon. Furthermore, the developed system allowed the implantation of the Fe as a catalytic material through steel sputtering of the high voltage acceleration anode during the EBI process. It was observed by HRTEM analyses that the rod-like particles are preferentially composed of highly oriented graphite in its bottom, polycrystalline graphite in its middle and magnetite nanoparticles in its top.
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The
invariant subspace problem
(ISP) for Hilbert spaces asks if every bounded linear operator has a non-trivial closed invariant subspace. Due to the existence of universal operators (in the sense of ...Rota) the ISP can be solved by proving that every minimal invariant subspace of a universal operator is one dimensional. In this work, we obtain conditions for
T
φ
∗
|
M
to have a non-trivial subspace where
M
⊂
H
2
(
D
2
)
is an invariant subspace of the Toeplitz operator
T
φ
∗
on the Hardy space over the bidisk
H
2
(
D
2
)
induced by the symbol
φ
∈
H
∞
(
D
)
. We then use this fact to obtain sufficient conditions for the ISP to be true.
The use of electrical impedance spectroscopy in point-of-care systems or for online monitoring has been hampered by the high cost of typical benchtop impedance analyzers. In this article, we ...introduce a portable, low-cost impedance analyzer, referred to as "Simple-Z," which contains a signal processing unit that allows for a precise generation and reading of the excitation and response signals. Simple-Z is based on the integrated circuit AD5933 in conjunction with peripheral circuits for a fine output amplitude regulation, flexible response amplification, sampling rate control, automatic calibration, and external communication. Software solutions were implemented, including the strategical register overflow to allow decreasing frequency sweeps, the control of the number of acquisition cycles to reduce the spectral leakage of the discrete Fourier transform (DFT), and the iterative approximation for defining proper response amplification and calibration resistances. The software also included a graphical user interface (GUI) with entries, buttons, and graphs that allow for an intuitive usage of the device. Results generated with Simple-Z in equivalent circuits mimicking sensing systems and in aqueous solution of different Na2SO4 concentrations were essentially identical to those obtained with a commercial benchtop impedance analyzer. Since the cost of the circuitry and components to fabricate an instrument is near U.S. <inline-formula> <tex-math notation="LaTeX">{\}100 </tex-math></inline-formula> and because Simple-Z was designed to allow for easy upscale to mass production, one may expect it to be deployed in point-of-care diagnosis systems. Furthermore, it can also be used in teaching laboratories for training students in electrical impedance spectroscopy.
Background Outcomes of catheter ablation of atrial fibrillation (AF) are variable and the predictors of success require further elucidation since the identification of correctable risk factors could ...help to optimize therapy. We aimed to assess the impact of body mass index (BMI) in the overall safety and efficacy of catheter ablation of AF, with emphasis on the use of cryoballoon ablation and novel oral anticoagulants. Methods and Results There were 2497 consecutive patients undergoing catheter ablation of AF in 7 European high volume centers were stratified according to BMI (normal weight <25 kg/m
, pre-obese 25-30 kg/m
, obesity 30-35 kg/m
, and morbid obesity ≥35 kg/m
) and comparisons of procedural outcomes evaluated. Pre-obese and obese patients presented more comorbidities (hypertension, diabetes mellitus, and sleep apnea), and had higher rates of non-paroxysmal AF ablation procedures. The rate of atrial 12-month arrhythmia relapse increased alongside with BMI (35.2%, 35.7%, 43.6%, and 48.0%
<0.001). During a median follow-up of 18.8 months (interquartile range 11-28), after adjusting for all baseline differences, BMI was an independent predictor of relapse (hazard ratio=1.01 per kg/m
; 95% CI 1.01-1.02;
=0.002), adding incremental predictive value to obstructive sleep apnea. BMI was not a predictor for any of the reported complications. Using novel oral anticoagulants and cryoballoon ablation was safe and efficacy was comparable with vitamin-K antagonists and radiofrequency ablation. Conclusions Obese patients present with a more adverse comorbidity profile, more advanced forms of AF, and have lower chances of being free from AF relapse after ablation. Use of novel oral anticoagulants and cryoballoon ablation may be an option in this patient group.
This paper presents a solution for energy microgeneration through energy harvesting by taking advantage of temperature differences that are converted into electrical energy using the Seebeck effect. ...A thermoelectric microconverter for energy scavenging systems that can supply low-power electronics was fabricated using thin films of bismuth and antimony tellurides. Thin films of n-type bismuth (Bi 2 Te 3 ) and p-type antimony (Sb 2 Te 3 ) tellurides were obtained by thermal coevaporation with thermoelectric figures of merit (ZT) at room temperature of 0.84 and 0.5 and power factors (PF × 10 -3 W · K -1 ·m-2) of 4.87 and 2.81, respectively. The films were patterned by photolithography and wet-etching techniques. The goal for this thermoelectric microconverter is to supply individual electroencephalogram (EEG) modules composed by an electrode, processing electronics, and an antenna, where the power consumption ranges from hundredths of microwatts to a few milliwatts. Moreover, these wireless EEG modules allow patients to maintain their mobility while simultaneously having their electrical brain activity monitored.
Objectives/Hypothesis
The objectives of this study were to evaluate laryngeal inflammation and mucosal integrity in a murine model of reflux disease and to assess the protective effects of topical ...agents including alginate, hyaluronic acid, and cashew gum.
Study Design
Animal study.
Methods
A surgical murine model of reflux disease was evaluated at 3 or 7 days postsurgery, and laryngeal samples were collected to measure inflammation (wet weight and myeloperoxidase MPO) and mucosal integrity (transepithelial resistance TER and mucosal permeability to fluorescein). Additional groups of animals were administered one of several topical agents (alginate, hyaluronic acid, or cashew gum) daily, and laryngeal inflammation and mucosal integrity were evaluated at 3 days postsurgery.
Results
At 3 days, and not 7 days postsurgery, we observed increased laryngeal wet weight and MPO, decreased laryngeal TER, and increased laryngeal mucosa permeability. Alginate partially decreased laryngeal inflammation (wet weight and not MPO) and dramatically improved laryngeal mucosal integrity. Conversely, hyaluronic acid eliminated the inflammation; however, it had no effect on laryngeal mucosal integrity impairment. Cashew gum eliminated laryngeal inflammation as well as the impairment in laryngeal mucosal integrity.
Conclusions
This study shows that a surgical model of reflux disease induced laryngeal inflammation and impairment in laryngeal barrier function. These observed alterations were partially attenuated by alginate and hyaluronic acid and completely reversed by cashew gum.
Level of Evidence
NA Laryngoscope, 2020
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