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Thoracic aortic aneurysm is one of the manifestations of Marfan syndrome (MFS) that is known to affect men more severely than women. However, the incidence of MFS is similar between men and women. The aim of this study is to show that during pathological aortic dilation, sex-dependent severity of thoracic aortopathy in a mouse model of MFS translates into sex-dependent alterations in cells and matrix of the ascending aorta, consequently affecting aortic biomechanics. Fibrillin-1 C1041G/+ (Het) mice were used as a mouse model of MFS. Ultrasound measurements from 3 to 12 mo showed increased aortic diameter in Het aorta, with larger percentage increase in diameter for males compared with females. Immunohistochemistry showed decreased contractile smooth muscle cells in Het aortic wall compared with healthy aorta, which was accompanied by decreased contractility measured by wire myography. Elastin autofluorescence, second-harmonic generation microscopy of collagen fibers, and passive biomechanical assessments using myography showed more severe damage to elastin fibers, increased medial fibrosis, and increased stiffness of the aortic wall in MFS males but not females. Male and female Het mice showed increased expression of Sca-1-positive adventitial progenitor cells versus controls at young ages. In agreement with clinical data, Het mice demonstrate sex-dependent severity of thoracic aortopathy. It was also shown that aging exacerbates the disease state especially for males. Our findings suggest that female mice are protected from progression of aortic dilation at early ages, leading to a lag in aneurysm growth. NEW & NOTEWORTHY Male Fbn1(C1041G/+) mice show more severe thoracic aortic changes compared with females, especially at 12 mo of age. Up to 6 mo of age, Sca-1(+) smooth muscle progenitor cells are more abundant in the adventitia of both male and female Fbn1 Het mice compared with wild types (WTs). Male and female Het mice show similar patterns of expression of Sca-1(+) cells at early ages.

Luminescent solar concentrators (LSCs) are considered promising photovoltaic (PV) devices to circumvent practical issues of applying conventional solar panels to the built environment. However, LSCs suffer from low power conversion efficiencies (PCEs) (typically &lt, 2% for devices of over 1 m2), despite numerous efforts having been made to develop novel luminescent materials and optical techniques. In this report, we proposed to utilize photothermal (PT) energy of the LSCs to further improve the PCE. We conducted a preliminary investigation on the PV and PT properties of an LSC with dimensions of 300 mm × 300 mm × 5 mm. The results showed that the PT power (27.05 W) was much higher than the PV power (2.12 W). Further analysis indicated that the PCE could reach 3.41% for a device of 1 m2.

Harvesting solar energy for catalytic conversion of CO2 into valuable chemical fuels/feedstocks is an attractive yet challenging strategy to realize a sustainable carbon-cycle utilization. Homogene...

In this report, we introduced subwavelength sanding treatment to boost the cost-effectiveness of luminescent solar concentrators (LSCs). It was proven the hypothesis that sanding the device surface to roughness (Rq = 22–105-nm) much smaller than the wavelength of sunlight (λ = 280–4000 nm) would improve the device performance due to much higher scattering gain than scattering loss. Experimental results showed that the sanded devices exhibited power conversion efficiency (ηLSC) and power concentration ratio (C) enhanced by at least 44% and could have the doping concentration of the luminophores significantly reduced by 87.5%. Measurement on the waveguide edge emission revealed that the performance enhancement was attributed to the utilization of the long-wavelength (λ > 800 nm) photons. Monte Carlo ray tracing simulation signified that the subwavelength sanding treatment was also applicable to large-area devices with geometric gain (G) up to 120 (9.29 m2) and devices made of other luminophores. Cost-effectiveness analysis indicated a huge reduction by 45% in the price per watt (PPW) for large-area commercial-sized (80 in. by 40 in.) LSCs. This study suggested that subwavelength sanding treatment was promising to bridge the gap between research and commercialization of the LSCs.

A fine tunable parity-time symmetric optoelectronic oscillator (PT-OEO) based on laser wavelength tuning is proposed and experimentally demonstrated. In the PT-OEO, an intensity modulator (IM) and a dispersion compensating fiber (DCF) are merged into the loop. Tuning the laser wavelength leads to a reconfigurable dispersion-induced power fading, serving as rough tunable oscillation mode selection. Meanwhile, to implement a fine-mode selection, parity-time symmetry breaking is introduced. Consequently, a fine tunable PT-OEO is achieved without using a high quality-factor (Q-factor) electrical filter. Experiment shows that the frequency of the generated signal can be tuned from 20.34 to 19.49 GHz with a step of 203 MHz, when the laser wavelength is manipulated from 1545 to 1565 nm. The phase noise is evaluated as −116.1 dBc/Hz @ 10-kHz offset frequency.

The use of luminescent solar concentrators (LSCs) is considered a promising option to impart energy harvesting capability to buildings with minimal alternation to the building structure. To fill the gap between fundamental research and practical application, this study investigated the performance (power conversion efficiency, ηLSC and power concentration ratio, C) of the LSCs of different sizes under different light conditions including simulated sunlight condition, outdoor sunny, overcast and raining conditions, and indoor condition employing four different types of light bulbs (i.e., incandescent, halogen, fluorescent and light-emitting diode). It was observed that the LSCs exhibited higher one-sun performance under outdoor sunny condition than under simulated sunlight. Under overcast and raining conditions, ηLSC decreased significantly with the increase of the device size. Under indoor incandescent and halogen light conditions, the LSCs exhibited low ηLSC due to the low percentage of the visible portion in the light spectrum. Surprisingly high ηLSC boosted by 50% compared to the outdoor sunny condition was obtained in the LSCs under fluorescent and LED light conditions. This research suggested very promising application of the LSCs in indoor light energy recycling, which has not been proposed before.

Judging the degree of humor in natural language texts is a very important issue in natural language processing. This paper takes edited news headlines as the research object and studies how to use a neural network to predict the degree of humor. Our main purpose is to explore the method of combining neural networks and traditional humor theory, to be specific, is to automatically evaluate the humor degree of news headlines, which includes original news headlines and modified news headlines. This paper designs a prediction model of humor degree based on RoBERTa, which contains three information extractors. And the classic models in deep learning, LSTM, and CNN and the recent popular models, Bert and RoBERTa, were selected as comparative models for experiments. The results prove that our proposed method can effectively improve the prediction effect of the neural network model.

The present study compares typical measurements of bubble dynamics obtained with a 4-point optical probe over the same range of superficial gas velocity in the same size gas–liquid contactor in two different systems. The classical bubble column (BC) arrangement employed air bubbled through water. The photo-bioreactor (PBR) used a growing algae in appropriate culture solution. Local gas holdup distribution across the vessel was monitored, as well as the local distribution of bubble velocity, bubble chord length, bubble frequency and interfacial area per unit volume for both systems. It was observed these parameters were significantly different in the photo-bioreactor. This information coupled with the tracer absorption studies with oxygen provided the needed information to evaluate the gas liquid volumetric mass transfer coefficients from an appropriate model for both systems. The development of such a model is described. It was concluded that the difference in hydrodynamics of the two systems was due to difference in physicochemical properties.

This demo presents NativeHelper, a bilingual Chinese-English sentence search engine that aims to provide assistance for non-English academic writers. As opposed to most existing bilingual sentence search engines that rely heavily on parallel corpora, our system is built on monolingual sentence corpus and bilingual dictionaries which are more readily available. The system is implemented based on a large-scale English sentence database and a simple yet practically efficient bilingual language model. A screen cast is available at https://www.youtube.com/watch?v=oNYOYPDeTyM.

Luminescent solar concentrators (LSCs) are light-guides doped with luminophores that can spectrally and spatially concentrate solar radiation. With the ability to harvest both direct and diffuse light, LSCs are considered attractive prospects for building-integrated photovoltaic applications. However, it is still challenging to develop organic luminophores based large-area LSCs that work well in various illumination conditions. Reabsorption, caused by small stokes shift of typical organic luminophores, often limits the performance of large-area LSCs. This study reports an indoor and outdoor performance of large-area (≥100 cm2) LSCs that employ a donor-acceptor luminophore with a large Stokes shift. The largest (400 cm2) LSC demonstrates an optical efficiency (ηopt) of 5.5% and 7.6% under outdoor (AM 1.5G) and indoor (white LED) illuminations, respectively. Furthermore, the aesthetic and visual comfort parameters such as chromaticity coordinates, color rendering index, and average visible transmission are obtained that suggest the suitability of our LSCs for a built environment.

In this paper, polymer-dispersed liquid crystal (PDLC) films which based on the acrylate and the thiol monomers were first prepared by ultraviolet-initiated polymerisation. The electro-optical properties and morphologies of the PDLC films were systematically investigated. The functionality of thiol monomers and their feed ratio showed great influence on the properties of the fabricated PDLC films because of the existence of competition between thiol–acrylate reaction and acrylate monomer polymerisation reaction. This made the polymer network and electro-optical properties of the PDLC films easily tunable by the introduction of the thiol monomers. When added four-functional thiol monomer PETMP with appropriate concentration into the PDLC system, lower driven voltage and higher contrast ratio were achieved.

Measuring the spectral response (SR) of large-area ( > 100 c m 2 ) luminescent solar concentrators (LSCs) has proven difficult because common laboratory photovoltaic (PV) instruments that offer monochromatic incidence measure devices with limited sizes (typically < 50 c m 2 ). This report addresses this issue through a method called regional measurements. In this method, large-area LSCs are configured to small surface and edge regions, which are sequentially illuminated and measured, respectively. The measured SRs of large-area LSCs are consistent with those from the conventional method and the Monte Carlo ray-tracing simulation. This method is also applied to analyze scattering effects in the LSCs, showing the relationships of the scattering-induced power gain and power loss to the surface root-mean-squared roughness ( R q ) of the devices. The results explain why the PV performance of the LSCs can be improved through proper surface scattering treatment.

In this study, we propose to improve the photostability of large-area (up to 19.35 cm2) printed organic photovoltaics (OPVs) through luminescent solar concentrators (LSCs), which convert high-energy short-wavelength (λ 600 nm) photons. We investigate the impacts of the luminophore concentration and waveguide surface roughness on the power conversion efficiency (PCE) of the OPV-LSCs with sizes from 1 inch (2.54 cm) to 12 inches (30.48 cm), corresponding to front surface areas from 6.4516 cm2 to 929.0304 cm2. For the 6-inch (232.26-cm2) OPV-LSCs, the results show that a high waveguide surface roughness (Rq = 63 nm) leads to devices with a high device PCE (ηLSC = 0.93%) and wide external quantum efficiency (EQE) from 400 nm to 800 nm. Detailed edge emission analysis on the luminescent waveguides indicates an edge emission with a large fraction (>95%) of long-wavelength photons comprised of a large fraction (>25%) of near-infrared (NIR) (λ > 700 nm) light. This leads to the photostability (defined as the hours when the PCE drops by 10%) of the OPV-LSCs significantly improved to 320 h under continuous 1 sun illumination (the photostability of the OPVs is only 25 h). The approach of OPV-LSCs paves the way to practically improve the photostability of large-area printed OPVs.

Polymer-dispersed liquid crystal (PDLC) films were prepared by the ultraviolet-light-induced polymerization of photopolymerizable monomers in nematic liquid crystal/chiral dopant/thiol-acrylate reaction monomer composites. The effects of the chiral dopant and crosslinking agents on the electro-optical properties of the PDLC films were systematically investigate. While added the chiral dopant S811 into the PDLC films, the initial off-state transmittance of the films was decreased. It was found that the weight ratio among acrylate monomers, thiol monomer PETMP and the polymercaptan Capcure 3-800 showed great influence on the properties of the fabricated PDLC films because of the existence of competition between thiol-acrylate reaction and acrylate monomer polymerization reaction. While adding polymercaptans curing agent Capcure 3-800 with appropriate concentration into the PDLC system, lower driven voltage and higher contrast ratio were achieved. This made the polymer network and electro-optical properties of the PDLC films easily tunable by the introduction of the thiol monomers.

An optical fiber reflectance probe is developed for fast, in situ detection of phase transitions between heterogeneous and homogeneous states in multiphase systems. Experiments with two binary syst...

In this study, a polymer dispersed cholesteric liquid crystal (PDChLC) film obtained via a one-step fabrication technique based on photopolymerization of a thiol-acrylate reaction system was prepared and characterized for the first time. The effects of the chiral dopant, the influence of thiol monomer functionality and content on the morphology and subsequent performance of the PDChLC films were systematically investigated. It was demonstrated that the addition of a small amount of chiral dopant slightly increased the driving voltage, but decreased the off-state transmittance significantly. Furthermore, scanning electron micrographs (SEM) shown that the liquid crystal (LC) droplet size decreased at first and then increased with the increasing amount of thiol monomer functionality, while increasing the thiol content increased the LC droplet size. Correspondingly, the electro-optical switching behavior was directly dependent on LC droplet size. By tuning the raw material composition, PDChLC film with optimized electro-optical performance was prepared.

We report a thin-film optical diode written into thin films of a liquid-crystalline polymer (LCP), which is based on the photoinduced LC-to-isotropic phase transition of LCPs. The interference pattern between a collimated and a focused UV laser beam is imprinted as chirped volume-phase gratings in photoresponsive LCP films and no further processing steps like development or liftoff are required for the fabrication. The resultant thin-film device not only possesses the fundamental functions of an optical lens for laser beam focusing, but also shows diode effects with the focusing/defocusing function dependent on the direction of light incidence and orientation of the device. Furthermore, this photonic thin-film lens exhibits a spatially tunable spectroscopic response, revealing a unique physics of secondary excitations of resonance modes of the single-layer LCP waveguide grating structures. This reveals the mechanisms for the focusing/defocusing of laser beams by chirped grating structures. Erasability and reconstructibility of the photoresponsive LCPs guarantee rewritability of the thin-film diode lens.