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In ultrawide bandgap (UWBG) nitride and oxide semiconductors, increased bandgap (Eg) correlates with greater ionicity and strong electron–phonon coupling. This limits mobility through phonon scattering, localizes carriers via polarons and self-trapping, broadens optical transitions via dynamic disorder, and modifies the breakdown field. Herein, we use polarized optical transmission spectroscopy from 77 to 633 K to investigate the Urbach energy (Eu) for many orientations of Fe- and Sn-doped β-Ga2O3 bulk crystals. We find Eu values ranging from 60 to 140 meV at 293 K and that static (structural defects plus zero-point phonons) disorder contributes more to Eu than dynamic (finite temperature phonon-induced) disorder. This is evidenced by lack of systematic Eu anisotropy, and Eu correlating more with x-ray diffraction rocking-curve broadening than with Sn-doping. The lowest measured Eu are ∼10× larger than for traditional semiconductors, pointing out that band tail effects need to be carefully considered in these materials for high field electronics. We demonstrate that, because optical transmission through thick samples is sensitive to sub-gap absorption, the commonly used Tauc extraction of a bandgap from transmission through Ga2O3 >1–3 μm thick is subject to errors. Combining our Eu(T) from Fe-doped samples with Eg(T) from ellipsometry, we extract a measure of an effective electron–phonon coupling that increases in weighted second order deformation potential with temperature and a larger value for E||b than E||c. The large electron–phonon coupling in β-Ga2O3 suggests that theories of electrical breakdown for traditional semiconductors need expansion to account not just for lower scattering time but also for impact ionization thresholds fluctuating in both time and space. [ABSTRACT FROM AUTHOR]

We investigate the propagation characteristics of two temporally separated soliton pulses with the same spectra, under the influence of stimulated Raman scattering, within a single-mode optical fiber. This analysis explores the behavior of the interacting solitons while propagating in different chalcogenide materials, exhibiting new features and promising prospects for soliton transmission in optical communication systems. Our study included all the interaction parameters constituting the nonlinear Schrödinger equation (NLSE). We have examined the relationship between the Kerr nonlinearity, interpulse and intrapulse Raman effects, and material-dependent collision length featuring a key aspect in logic design and phase control in mode-locking systems. We have also systematically shown the manifestation of the Raman response function from the Raman gain curve, which our mathematical model (the Lorentzian model) provides, that exhibits a near agreement with experimental data. Our findings reveal significant differences from the typical behavior of two-soliton interaction only due to Kerr nonlinearity. Furthermore, we have investigated the mechanism of the net energy transfer between the interacting solitons as an integral phenomenon involved in multiple soliton propagation. These results provide an insightful understanding of the associated nonlinear effects in high-power soliton transmission systems and are foreseen to possess the potential for designing advanced optical switches and mode-locked lasers. [ABSTRACT FROM AUTHOR]

With the in-depth study of open optical systems, the topological phases of non-Hermitian metasurfaces have attracted increasing attention due to their topological protection properties. Here, in this paper, a tunable non-Hermitian metasurface with bidirectional anisotropism is proposed. By incorporating the phase change material vanadium dioxide (VO2) into the metasurface, two topological exceptional points (EPs) appear in the system by adjusting the conductivity of VO2 and chiral responses appear at both EPs. This research shows that the conductivity significantly affects the reflection of the metasurface, and the zero-reflection points correspond to the EPs of the non-Hermitian system. Further results prove that circling around EPs leads to a 2π phase change, which is topologically protected and independent of the encirclement path. Therefore, this study employs an active control approach to realize two topological EPs. Through comprehensive investigations into the topological properties and chiral performance at EPs, we elucidate the mechanism for the chirality generation in non-Hermitian metasurfaces, which offers feasible solutions for the development of chiral topological devices and light transmission and modulation in future applications. [ABSTRACT FROM AUTHOR]

Due to the incoherent superposition of various color light transmission matrices (TMs) in space, it has always been a challenge to measure the multi-color light TMs directly or indirectly in the field of wavefront shaping. In this paper, a hybrid algorithm for indirectly measuring the TMs of multi-color light is proposed. The prominent feature of this algorithm is that the spatial and frequency domain information of the speckle patterns is simultaneously input into the multi-input fully connected neural network. Compared with previous spatial data-driven methods, our method can better learn the mapping relationships hidden behind the color samples, making the measurement of the TMs of multi-color light through the scattering media more accurate. Experimental results show that the enhancement factor of multi-point multi-color light focusing using the hybrid algorithm is improved by about 27% compared with the genetic algorithm, and the number of iterations is reduced by about 47%. The hybrid algorithm presents a new idea for multi-color light focusing, which is of great significance for wavefront shaping in complex optical fields. [ABSTRACT FROM AUTHOR]

Ge 2 Sb 2 Te 5 (GST), a phase change material, generally exhibits two-step crystallization (amorphous → fcc → hcp) to store and process data. The present study reports the crystallization behavior and bonding mechanism of Ga-doped GST thin films with thermal annealing. Ga doping results in the formation of Ga–Te bonds and shows no bonding with other host elements (Ge and Sb), which changes the bonding mechanism and leads to one-step crystallization (amorphous → fcc). The optical transmission contrast confirmed the thermal stabilization of the fcc phase with thermal annealing. These findings suggest that Ga doping into GST thin films has thermally stabilized the metastable fcc phase and suppressed the hcp phase, hence posing it as a potential candidate for phase change memory applications with fast processing speed and low power consumption. [ABSTRACT FROM AUTHOR]

Flexible materials with negative Poisson's ratio exhibit unique mechanical properties, which combined with other excellent optoelectronic properties will facilitate the nanoscale applications with complex functionalities. Based on first-principles calculations, we uncover a transparent two-dimensional pentagonal material, penta-CdO 2 , exhibiting dynamic, thermal, thermodynamic and mechanical stability. Penta-CdO 2 possesses excellent mechanical flexibility with larger negative Poisson's ratio of −0.47 than that of penta-graphene and good mechanical ductile property with a large ultimate strength. On the other hand, penta-CdO 2 is an indirect band gap semiconductor with a band gap of 3.28 eV concomitant with band-convergence characteristics, and its band edges fully span the redox potentials of water with excellent robustness across wide pH conditions and strain ranges. Furthermore, penta-CdO 2 exhibits good solar light absorption performances, nearly 100% transmission to visible light, high carrier mobility and anisotropy ratio, as well as favorable hydrogen evolution reaction free energy (Δ G H * = −0.64 eV), indicating its potential application as a photocatalyst for water splitting. The present theoretical prediction not only enriches the family of two-dimensional pentagon-based materials, but also uncovers its potential application prospects in flexible mechanics, optoelectronics, and photocatalytic water splitting. • Uncover a transparent 2D pentagonal material penta-CdO 2 by structure searching. • Excellent mechanical flexibility with larger NPR (−0.47) than that of penta-graphene. • Indirect band gap semiconductor concomitants with band-convergence characteristics. • Good solar light absorption, nearly 100% transmission, anisotropic carrier mobility. • Favorable hydrogen evolution reaction free energy (−0.64 eV) for water splitting. [ABSTRACT FROM AUTHOR]

For cardiopathy patients with an implanted cardiac pacemaker, supplying power to the pacemaker is a challenging problem. In this study, we aim to design a transcutaneous optical energy transmission system that transmits optical energy from an optical-energy-generating circuit to a receiving circuit in a human body through the skin to charge the pacemaker's battery such that the battery supplies power to the pacemaker continuously. We use 0.5-mm-thick pigskin to imitate human skin tissue. The light source of the system is a halogen lamp and the receiver is a solar cell. The beam emitted by a the halogen lamp is transmitted to the solar cell through the skin generating a photovoltaic effect so as to charge the rechargeable button battery. As optical energy is received by a four-solar-cell module, we adopt a Zener voltage regulation circuit and a pure resistance circuit to charge the battery. Experimental data show that if a four-solar-cell module is used to charge a battery with the voltage regulation circuit, the battery after 62 h of charging stores enough power to operate the pacemaker for 20--35 days. On the other hand, charging the battery using the pure resistor circuit can reduce the charging time from 62 h to 14 h for the same number of operation days. If the number of solar cells in parallel is increased to 12, the charging time for the same number of operation days can be shortened from 14 h to 12 h with the pure resistance circuit. As a result, transcutaneous remote charging is achieved. Approaches to shorten the charging time and future works are proposed as well. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the phenomenon of optomechanically induced transparency (OMIT) in a cavity that has a moving end mirror and is subjected to an external force. Furthermore, we place an optical parametric amplifier (OPA) inside the cavity. We show that the transmission intensity of the probe field and the group delay is enhanced by the parametric gain and phase of the OPA. We also show that this enhancement is influenced by external forces. We believe that these findings could be valuable in the area of quantum information processing. [ABSTRACT FROM AUTHOR]

Imaging and characterizing the dynamics of cellular adhesion in blood samples is of fundamental importance in understanding biological function. In vitro microscopy methods are widely used for this task but typically require diluting the blood with a buffer to allow for transmission of light. However, whole blood provides crucial signaling cues that influence adhesion dynamics, which means that conventional approaches lack the full physiological complexity of living microvasculature. We can reliably image cell interactions in microfluidic channels during whole blood flow by motion blur microscopy (MBM) in vitro and automate image analysis using machine learning. MBM provides a low cost, easy to implement alternative to intravital microscopy, for rapid data generation where understanding cell interactions, adhesion, and motility is crucial. MBM is generalizable to studies of various diseases, including cancer, blood disorders, thrombosis, inflammatory and autoimmune diseases, as well as providing rich datasets for theoretical modeling of adhesion dynamics. Monitoring cellular adhesion in blood samples is of fundamental importance, but conventional approaches may not capture the full physiological complexity of microscale flow in living contexts. Here, the authors present motion blur microscopy and machine learning-based image analysis to study cell interactions in microfluidic channels during whole blood flow. [ABSTRACT FROM AUTHOR]

Next-generation energy-efficient photonic integrated systems, such as neuromorphic computational chips require efficient heterogeneous integration of ultracompact light sources and photodetectors through highly dense waveguide circuits. However, interconnecting these devices in emitter-receiver communication circuits remains a challenge and an obstacle towards upscaling heterogeneous photonic chips. Here we report on versatile air-cladded free-standing 3D polymer waveguides (OrmoCore, n≈1.5) spanning up to 900 µm in length without intermediate mechanical support structures, microprinted via two-photon polymerization. The presented waveguides are suitable for on-chip out-of-plane light coupling as well as non-connected 3D crossings, needed for high density optical circuits. The waveguides show optical transmission losses of 1.93 dB mm−1 at λ = 635 nm, and of 3.71 dB mm−1 at λ = 830 nm in the wavelength range of GaAs-based microLEDs spectral emission. On-chip imaging for high-precision alignment and TPP microfabrication are performed seamlessly by utilizing the same laser source for both steps, allowing accurate 3D printing on microstructured substrates. As proof of concept, we interconnect two GaAs-based microLEDs via an on-chip microprinted 3D waveguide. Such combined systems can serve as building blocks of future complex integrated heterogeneous photonic networks. [ABSTRACT FROM AUTHOR]

Fiber optic localized surface plasmon resonance (LSPR) sensors have become an effective tool in refractive index (RI) detection for biomedical applications because of their high sensitivity. However, using conventional optical fiber has caused limitations in implanting the sensor in the body. This research presents the design and construction of a new type of polymer-based LSPR sensors to address this issue. Also, finite element method (FEM) is used to design the sensor and test it theoretically. The proposed polymer optical fiber (POF) based on citrate is biocompatible, flexible, and degradable, with a rate of 22% and 27 over 12 days. The step RI structure utilizes two polymers for light transmission: poly (octamethylene maleate citrate) (POMC) as the core and poly (octamethylene citrate) (POC) as the cladding. The POF core and cladding diameters and lengths are 700 µm, 1400 µm, and 7 cm, respectively. The coupling efficiency of light to the POF was enhanced using a microsphere fiber optic tip. The obtained results show that the light coupling efficiency increased to 77.8%. Plasma surface treatment was used to immobilize gold nanoparticles (AuNPs) on the tip of the POF, as a LSPR-POF sensor. Adsorption kinetics was measured based on the pseudo-first-order model to determine the efficiency of immobilizing AuNPs, in which the adsorption rate constant (k) was obtained be 8.6 × 10–3 min−1. The RI sensitivity of the sensor in the range from 1.3332 to 1.3604 RIU was obtained as 7778%/RIU, and the sensitivity was enhanced ~ 5 times to the previous RI POF sensors. These results are in good agreement with theory and computer simulation. It promises a highly sensitive and label-free detection biosensor for point-of-care applications such as neurosciences. [ABSTRACT FROM AUTHOR]

Semitransparent organic photodetectors (ST‐OPDs) show immense promise for integration into optoelectronic devices, offering adjustable absorption and see‐through functionalities. However, achieving high‐performance ST‐OPDs remains challenging, necessitating a delicate balance of low dark current density, high external quantum efficiency, and optimal visible light transmission. Here, a strategy is presented using anode interfacial materials (AIMs) as the donor and narrow bandgap non‐fullerene acceptors (NFAs) to formulate the donor: acceptor light‐sensitive layer. Critical to the approach is the incorporation of 1,8‐diiodooctane during film processing, enabling the formation of morphology with an NFA molecular crystal network embedded within the donor polymer matrix. This optimized morphology substantially boosted device external quantum efficiency and reduced dark current under reverse bias, yielding a remarkable special detectivity of over 1013 Jones at 840 nm under a bias of −0.1 V. ST‐OPDs are achieved with detectivity surpassing 1012 Jones and notable average visible transmittance of over 50%. These findings highlight the potential of AIM:NFA combinations for high‐efficiency ST‐OPDs by finely controlling morphology through multiple length scales, opening doors for various applications in transparent electronics and beyond. [ABSTRACT FROM AUTHOR]

AbstractPurposeMethodsResultsConclusionNeodymium yttrium aluminum garnet (Nd:YAG) laser capsulotomy is considered gold standard in the treatment of posterior capsule opacification (PCO). In this laboratory study, we measured spectral transmission to evaluate the image contrast and analyze the impact of Nd:YAG associated defects in presbyopia-correcting intraocular lenses (IOLs).Two hydrophobic, acrylic IOLs as classic multifocal lenses with diffractive ring segments and different amount of near addition (A, B), one hydrophilic, trifocal IOL (C), one sector-shaped, plate haptic IOL (D) and one hydrophobic, enhanced depth of focus (EDOF) IOL (E) were studied. Measurements included surface topography characterization, United States Air Force resolution test chart (USAF) analysis, spectral transmittance measurements and through focus contrast measurement. Measurements were done with unaltered samples, damages (n = 7) were intentionally created in the central 3.5 mm zone using a photodisruption laser (2.0 mJ) and measurements were repeated.Significant differences were shown between unmodified samples and samples with YAG pits. The YAG-pits decreased the image contrast and spectral transmission and changed results of USAF test images. The imaging contrast decreased to 66%, 64%, 60%, 52% and 59% with the YAG shots in samples (A-E). The light transmission decreased to 88%, 87%, 92%, 79% and 91% (A-E) on average between 400 nm to 800 nm. In all IOLs a reduction of the relative intensity of transmitted light was observed.The image performance of all tested presbyopia-correcting IOLs is significantly influenced and disturbed by YAG-pits. The intensity of transmitted light is reduced in the wavelength between 450–800 nm. USAF test targets show worse results compared to unmodified samples and contrast is significantly deteriorated. No ranking/rating among tested IOLs should be made as many other factors play a role in real world scenario. High care should be taken when performing Nd:YAG capsulotomy on premium IOLs to avoid any damages. [ABSTRACT FROM AUTHOR]

Attribute to their robustness against loss and external noise, nonreciprocal photonic devices hold great promise for applications in quantum information processing. Recent advancements have demonstrated that nonreciprocal optical transmission in linear systems can be achieved through the strategic introduction of loss. However, a crucial question remains unanswered: can loss be harnessed as a resource for generating nonreciprocal quantum correlations? Here, we take a counterintuitive stance by engineering loss to generate a vital form of nonreciprocal quantum correlations, termed nonreciprocal photon blockade. We examine a dissipative three-cavity system comprising two nonlinear cavities and a linear cavity. The interplay of loss and nonlinearity leads to a robust nonreciprocal single- and two-photon blockade, facilitated by destructive quantum interference. Furthermore, we demonstrate the tunability of this nonreciprocal photon blockade by manipulating the relative phase between the two nonlinear cavities. Remarkably, this allows for the reversal of the direction of nonreciprocity. Our study not only sheds a light on the concept of loss-engineered quantum nonreciprocity but also opens up a pathway for the design of quantum nonreciprocal photonic devices. [ABSTRACT FROM AUTHOR]

Photonic elements have greater information‐carrying capabilities compared to electronic components, making the development of high‐speed, chip‐integrated optical communication devices crucial for addressing interconnect bottlenecks in high‐speed computing systems. Significant progress has been made in studying light sources and their transmission. Despite these advancements, achieving a satisfactory integration of photonic circuits with both light source and optical waveguide functions has remained a challenge. Here, a silver nanowire (AgNW) waveguide‐integrated light source is demonstrated driven by alternating current (AC) voltage. AgNW functions as both the electrode and waveguide to simplify the device structure, and the 2D transition metal dichalcogenides (TMDs) monolayer acts as the gain media in device. The electroluminescence (EL) can be tunably modulated via adjusting the frequency and voltage of the AC in this device, and it is also successfully coupled into the waveguide with its transmission distance up to 25 µm. The experiments of electroluminescence and waveguide transmission of different materials and their interlayer excitons have made a preliminary exploration of multiple wavelength transmission. It provides a new research platform forward in the development of chip‐integrated optical communication devices, thereby hopefully addressing the interconnect bottleneck and unlocking the potential for enhanced performance and efficiency in high‐speed computing systems. [ABSTRACT FROM AUTHOR]

Long‐wave infrared photodetectors play an indispensable role in a variety of fields such as science, technology, engineering, and medicine. However, to date, most conventional long‐wave infrared photodetectors need to be operated under low temperature to meet the performance requirements. This can lead to a series of problems such as large device volume and high operating cost. Therefore, it is urgent to explore novel long‐wave photosensitive materials. In recent years, the development of nanotechnology has opened a new door for long‐wave infrared photodetection. Herein, pulsed‐laser deposition is successfully applied to the preparation of Ge‐doped BiTe (GBT) thin films. Importantly, the corresponding GBT photodetector exhibits excellent long‐wave infrared photosensitivity. Specifically, upon 10.5 µm illumination, the responsivity, external quantum efficiency, and detectivity reach 1.41 mA W−1, 0.017%, and 1.96 × 106 Jones, respectively. Moreover, a fast response rate with the rise/decay time down to 42.5/41.1 µs is realized. On this basis, the GBT photodetector is used as the receiving unit for optical signals to achieve proof‐of‐concept long‐wave optical information transmission application. On the whole, this study provides a new material platform for long‐wave optoelectronic sensing. [ABSTRACT FROM AUTHOR]

The traditional base station in C-RAN is divided into three parts: a pool of centralized baseband units (BBUs), a fronthaul network that links the BBUs and remote radio units (RRUs), and RRUs. This paper proposes a novel cooperative algorithm for resource optimization in a time-wavelength division multiplexed (TWDM) passive optical network (PON) incorporating a cloud radio access network (C-RAN). First, a joint collaborative strategy is deployed to optimize cooperative caching and transmission in the wireless and optical domains. Then, the quality of experience (QoE) is improved by bandwidth configuration and caching. Simulation results show that the average throughput of the proposed QoE-aware video cooperative caching and transmission mechanism (QACCTM) algorithm is approximately 30% higher than that of other algorithms. Compared with the relative average residual clutter power (RARCP) and quality-aware wireless edge caching (QAWEC) algorithms, the proposed QACCTM algorithm reduces the access delay by approximately 27.1% and 15.9%, respectively. [ABSTRACT FROM AUTHOR]

The defensive role performed by exogenously supplied ascorbic acid in the cyanobacterium Nostoc muscorum Meg1 against damages produced by UV-C radiation exposure was assessed in this study. Exposure to UV-C (24 mJ/cm2) significantly enhanced reactive oxygen species (ROS) (50%) along with peroxidation of lipids (21%) and protein oxidation (22%) in the organism. But, addition of 0.5 mM ascorbic acid prior to UV-C exposure showed reduction in ROS production (1.7%) and damages to lipids and proteins (1.5 and 2%, respectively). Light and transmission electron microscopic studies revealed that ascorbic acid not only protected filament breakage but also restricted severe ultrastructural changes and cellular damages in the organism. Although the growth of the organism was repressed up to 9% under UV-C treatment within 15 days, a pre-treatment with ascorbic acid led to growth enhancement by 42% in the same period. Various growth parameters such as photo-absorbing pigments (phycoerythrin, phycocyanin, allophycocyanin, chlorophyll a, and carotenoids), water splitting complex (WSC), D1 protein, RuBisCO, glutamine synthetase and nitrogenase activities in the UV-C treated organism were seen to be relatively intact in the presence of ascorbic acid. Thus, a detailed analysis undertaken in the present study was able to demonstrate that ascorbic acid not only act as first responder against harmful UV-C radiation by down-regulating ROS production, it also accelerated the growth performance in the organism in the post UV-C incubation period as an immediate response to an adverse experience presented in the form of UV-C radiation exposure. [ABSTRACT FROM AUTHOR]

Filter elements based on metamaterial structure are one of the essential schemes for researching the miniaturization of spectral detection systems. The aim of this study is to meet the application requirements of different long-wave infrared signal frequency filtering and improve the detection efficiency of micro-filters. In this paper, a periodic micro-nano-cross-linked hole structure is designed, based on the surface plasmonic polariton resonance effect to realize the extraordinary optical transmission performance of 8 ~ 12 μm long-wave infrared. Based on the surface plasmonic polariton excitation mechanism of periodic micro-nano-structures, the tunable performance of the transmission spectra at five central wavelengths of 8, 9, 10, 11, and 12 μm was achieved by changing the simulation period and the overall period of the model, and the optimal peak transmittance was 88.31% with a half-wave width of 1.31 ± 0.01 μm. The present study summarizes the tuning mode and rule of the micro-nano-cross-linked structure to realize the blue/redshift under the performance of the extraordinary optical transmission, which provides an important reference for the miniaturized structure design of infrared spectral detectors and tunable filtering research and is conducive to the application of broadband filtering spectral chips. [ABSTRACT FROM AUTHOR]

Auditory sensitivity and frequency resolution depend on the optimal transfer of sound‐induced vibrations from the basilar membrane (BM) to the inner hair cells (IHCs), the principal auditory receptors. There remains a paucity of information on how this is accomplished along the frequency range in the human cochlea. Most of the current knowledge is derived either from animal experiments or human tissue processed after death, offering limited structural preservation and optical resolution. In our study, we analyzed the cytoarchitecture of the human cochlear partition at different frequency locations using high‐resolution microscopy of uniquely preserved normal human tissue. The results may have clinical implications and increase our understanding of how frequency‐dependent acoustic vibrations are carried to human IHCs. A 1‐micron‐thick plastic‐embedded section (mid‐modiolar) from a normal human cochlea uniquely preserved at lateral skull base surgery was analyzed using light and transmission electron microscopy (LM, TEM). Frequency locations were estimated using synchrotron radiation phase‐contrast imaging (SR‐PCI). Archival human tissue prepared for scanning electron microscopy (SEM) and super‐resolution structured illumination microscopy (SR‐SIM) were also used and compared in this study. Microscopy demonstrated great variations in the dimension and architecture of the human cochlear partition along the frequency range. Pillar cell geometry was closely regulated and depended on the reticular lamina slope and tympanic lip angle. A type II collagen‐expressing lamina extended medially from the tympanic lip under the inner sulcus, here named "accessory basilar membrane." It was linked to the tympanic lip and inner pillar foot, and it may contribute to the overall compliance of the cochlear partition. Based on the findings, we speculate on the remarkable microanatomic inflections and geometric relationships which relay different sound‐induced vibrations to the IHCs, including their relevance for the evolution of human speech reception and electric stimulation with auditory implants. The inner pillar transcellular microtubule/actin system's role of directly converting vibration energy to the IHC cuticular plate and ciliary bundle is highlighted. [ABSTRACT FROM AUTHOR]

To investigate a near-infrared-to-blue luminescence upconversion curing method for polymerizing resin cements under zirconia discs. Lava zirconia discs of different thicknesses (0.5–2.0 mm) were manufactured. First, the transmittances of the NIR and two blue lights (BLs) (LED and halogen lights) through these discs were measured. Second, NaYF 4 :Yb3+/Tm3+ upconversion phosphor (UP) powder was milled into 0.5-μm particle sizes. A light-curable resin cement VariolinkII base was chosen as the control (UP0), and an experimental cement (UP5) was prepared by adding 5 % UPs. These two cements were examined using multiphoton excitation microscopy for particle distribution. UP5 and UP0 were polymerized with or without zirconia shielding then subjected to a microhardness test. A multifold analysis was performed to examine the effects of zirconia thickness, curing protocols (pure BL or combined BL and NIR curing), and cement type. The transmittance of NIR was superior to that of BL through zirconia discs of all thicknesses. UP particles were homogeneously distributed in UP5 and emitted blue luminescence under 980-nm NIR excitation. UP5 showed higher microhardness values than UP0 under any curing protocol or zirconia shielding condition. The combination of 20-s BL and 40-s NIR curing yielded the highest microhardness in uncovered UP5. However, combining 40-s BL and 20-s NIR curing surpassed the other groups when the zirconia discs were thicker than 0.5 mm. NIR exhibits higher transmission through zirconia than BL. UP particles work as strengthen fillers and photosensitizers in cements. NIR upconversion curing could be a new strategy for polymerizing resin cements under thick zirconia restorations. • An NIR activated upconversion reaction was used to induce blue light (BL) emission. • The transmittance of NIR through zirconia discs is higher than conventional BL. • Phosphor particles work as photosensitizers and strengthen fillers in cements. • Combining BL and NIR effectively enhanced polymerization of cements under zirconia. [ABSTRACT FROM AUTHOR]

Rotational speed measurement is important for many applications. Here, a noncontact rotational speed test method based on the detection of the periodically perturbed near-field microwave of an open-ended waveguide is proposed. Both simulations and experiments were conducted to verify the near-field microwave rotational speed sensor. The constructed rotation speed sensing system was composed of a standard open-ended WR-42 waveguide (in our measurements, a waveguide-to-coaxial adapter was used to represent an open-ended waveguide) working at ~18 GHz, a radio frequency (RF) circulator, a signal generator, a, RF detector and an oscilloscope. A rotating fan to be measured was placed close to the waveguide's mouth and, thus, the waveguide's reflection coefficient was periodically modulated by the rotating fan blades. Then, the RF detector converted this varying reflection coefficient into a direct current (DC) voltage, namely, a periodical waveform. Finally, the rotational speed of the fan could be extracted from this waveform. Measurements using both the proposed near-field microwave method and conventional optical transmission/reflection methods were conducted for verification. The effect of the rotating fan's location relative to the waveguide's mouth was also studied. The results show the following: 1. The proposed method works well with a rotational speed of up to ~5000 RPM (rounds per minute), and an accuracy of 1.7% can be achieved. 2. Metallic or non-metallic fan blades are all suitable for this method. Compared with the existing radar method, the proposed method may be advantageous for rotation detection in a constrained space. [ABSTRACT FROM AUTHOR]

In this paper a novel optical vector network analyzer (OVNA) utilizing a distributed feedback semiconductor optical amplifier (DFB-SOA) is introduced. The proposed OVNA is implemented by converting the transmission response of the optical device under test (ODUT) into the electrical domain. The main principle of the OVNA is predicated on the optical carrier restoration facilitated by the wavelength-selective amplification attribute of the DFB-SOA. The implemented OVNA effectively determined the transmission spectrum of an optical filter possessing a passband of 9-GHz bandwidth, achieving a commendable resolution of 25 MHz in the measurement process. The dynamic range of the OVNA can be broadened by adjust the driven current under the DFB-SOA. Additionally, the detection range of our system can be expanded through the utilization of broadband optoelectronic devices. Furthermore, the OVNA possesses considerable potential for integration onto a single chip. [ABSTRACT FROM AUTHOR]

High‐power optical transmission (HPOT) technology has emerged as a promising alternative among far‐field wireless power transmission approaches, enabling the transfer of kilowatts of power over kilometer‐scale distances. Its exceptional adaptability allows operation in challenging scenarios where traditional electrical wiring is impractical or unfeasible, thereby opening up a vast array of potential applications previously considered utopian. An important pending assignment in enhancing the performance of laser‐based HPOT systems is achieving efficient photovoltaic conversion of high power densities (≥10 W cm−2). In this sense, there is a pressing need for the advancement of optical photovoltaic converters (OPCs) capable of enduring intense monochromatic irradiances. This work presents the design optimization, manufacturing, and characterization processes of a gallium indium phosphide (GaInP)‐based OPC under varying 637 nm laser power at room temperature. In addition, methods to evaluate the impact of temperature on performance are provided. The findings reveal a maximum efficiency of 53.5% at 10 W cm−2, surpassing literature results for GaInP converters by over 9%abs at those light intensities. Remarkably, this device withstands unmatched irradiances within GaInP OPCs up to 60 W cm−2, maintaining 42.3% efficiency. This study aims to push forward the development of wide‐bandgap power converters with recordbreaking efficiencies paving the way for new applications. [ABSTRACT FROM AUTHOR]

Climate change is a growing threat to agriculture globally, with most substantial impacts expected in tropical smallholder systems such as cocoa farms in West Africa. Cocoa agroforestry is widely believed to enhance resilience to climatic extremes due to protection and a favourable microclimate under the shade trees. Morphological traits of many locally used shade tree species and their specific contribution to microclimate for climate-resilient cocoa production remain unclear. Therefore, aboveground morphology and sub canopy microclimate of eight common shade tree species were investigated in cocoa agroforestry systems in the Ahafo region, Ghana. Additionally, the growth of cocoa trees in three different distance zones to the shade tree stem was measured. The eight different shade tree species exhibited considerable variation in their impact on microclimate and cocoa growth. M. indica and M. excelsa allowed lowest light transmission, with the highest microclimatic buffering effect, i.e., reducing vapour pressure deficit and daily fluctuations of temperature and relative humidity. Cocoa trees around M. lucida and F. capensis were the highest in growth, characterized by height and stem diameter. However, a universally superior shade tree species could not be identified implying the need for shade tree diversity allowing various microclimatic conditions within an agroforestry system to spread risk of climate extremes. Cocoa tree growth was more affected by distance to the shade tree than by shade tree species, resulting in enhanced growth with distance to the stem. These findings provide a better understanding of species-related differences on cocoa growing conditions and climate change adaptation strategies. [ABSTRACT FROM AUTHOR]

The spectral signatures of optical absorbers, when combined with those of infrared molecules, play a critical role in constraining the cloud properties of exoplanet atmospheres. We aim to use optical transmission spectroscopy to confirm the tentative color signature previously observed by multiband photometry in the atmosphere of hot Jupiter HAT-P-55b. We observed a transit of the HAT-P-55b with the OSIRIS spectrograph on the Gran Telescopio Canarias (GTC). We created two sets of spectroscopic light curves, using the conventional band-integrated method and the newly proposed pixel-based method, to derive the transmission spectrum. We performed Bayesian spectral retrieval analyses on the transmission spectrum to interpret the observed atmospheric properties. The transmission spectra derived from the two methods are consistent, both spectrally resolving the tentative color signature observed by MuSCAT2. The retrievals on the combined OSIRIS and MuSCAT2 transmission spectrum yield a detection of Na at 5.5σ and a tentative detection of MgH at 3.4σ. The current optical-only wavelength coverage cannot constrain the absolute abundances of the atmospheric species. Space-based observations covering the molecular infrared bands or ground-based high-resolution spectroscopy are needed to further constrain the atmospheric properties of HAT-P-55b. [ABSTRACT FROM AUTHOR]

In the context of hydroelectric plants, this article emphasizes the imperative of robust monitoring strategies. The utilization of fiber-optic sensors (FOSs) emerges as a promising approach due to their efficient optical transmission, minimal signal attenuation, and resistance to electromagnetic interference. These optical sensors have demonstrated success in diverse structures, including bridges and nuclear plants, especially in challenging environments. This article culminates with the depiction of the development of an array of sensors featuring Fiber Bragg Gratings (FBGs). This array is designed to measure deformation and temperature in protective grids surrounding the turbines at the Santo Antônio Hydroelectric Plant. Implemented in a real-world scenario, the device identifies deformation peaks, indicative of water flow obstructions, thereby contributing significantly to the safety and operational efficiency of the plant. [ABSTRACT FROM AUTHOR]

The ability to manipulate the absorption, scattering, or reflectivity of light using synthetic materials has inspired innovations in nano‐ and micro‐materials for applications ranging from geoengineering to display optics. Asymmetric materials, like Janus particles, offer one solution to meet the needs of such technologies, as composition and geometry can be optimized to maximize directional optical properties in response to magnetic and/or electric fields, light, or electrostatic charge. In this work, a gram‐scale synthesis is applied to generate Janus matchstick particles comprising a gold head with a silica rod. Conditions are explored and optimized to elicit rotation of these matchstick particles under an alternating current (AC) electric field with varying field strength and frequency to maximize particle alignment. While only modest changes in transmission (≈8%) are observed over the visible spectral region with a bare silica rod, the application of an absorbing element increased transmission changes up to ≈23% demonstrating their utility as color‐changing materials. Experimental results are supported by theory and computation and highlight an important first step in activating directional optical effects in these materials which can be optimized for future adaptive technologies. [ABSTRACT FROM AUTHOR]

A nondiffracting propagation of an optical beam through a four-level double-V-type quantum system near a plasmonic nanostructure is investigated. We study the linear absorption and dispersion properties of the quantum system as it interacts with two laser fields. We discuss the effect of the control beam with a Laguerre-Gaussian (LG) profile on the focusing of the probe beam in the presence of a plasmonic nanostructure. An appropriately selected control beam excites one transition of the atomic system and generates a spatially varying refraction index modulation for a weak probe beam that couples to the other transition. We demonstrate that placing a plasmonic nanostructure at a nanometer distance from the atomic system and using a control field with the spatial structure leads to the diffraction-less propagation of the probe beam through the atomic system. Also, it is shown that the optical properties and probe beam focusing can be controlled by adjusting the distance of the plasmonic nanostructure from the atomic system. The proposed all-optical waveguide with high contrast and transmission can be used to implement applications such as image transfer through the medium and image processing. [ABSTRACT FROM AUTHOR]

The human body is susceptible to the adverse effects of exposure to ultraviolet (UV) radiation and high-energy shortwave blue light, which can increase the risk of skin cancer and eye damage. Consequently, light barrier materials have been developed to reduce the radiation hazards of UV and high-energy shortwave blue light. In this study, a novel photobarrier hydrogel was successfully prepared by free radical polymerization using hydroxyethyl methacrylate (HEMA), N-vinylpyrrolidone (NVP) and para-aminoazobenzene (PAAB) as comonomers in aqueous medium. The prepared hydrogels have a surface porous structure and remarkable thermal stability, with decomposition occurring at temperatures above 200 °C. The results of the ultraviolet visible transmission spectrum and light barrier effect experiments show the excellent light barrier rate of the material, with the hydrogel HNP-3 exhibiting a light barrier rate of over 71%. Cytotoxicity assay is performed to identify the favorable biocompatibility of the hydrogel, which can be attributed to the polymerization of PAAB onto polymeric chains. This process effectively inhibits the diffusion of PAAB into cells, thereby preventing adverse effects on cellular function. Based on these findings, it can be concluded that the hydrogel film materials in this study hold great potential for application in a range of applications that require protection of biological tissues such as the eyes and skin from UV or blue light. [ABSTRACT FROM AUTHOR]

With the demand for the development of lipid–polymer conjugates (LPCs) for biomedical applications, the development of novel, rapid, and efficient methods for the synthesis of LPCs is of great significance. In this study, a novel Y‐type photoinitiator (Lipid‐PI) containing a diacylglycerol group was first synthesized, and then the polymerization of conjugated vinyl monomers such as oligoethylene glycol methyl ether methacrylate (OEGMA) and N,N‐dimethylacrylamide could be rapidly initiated by the Lipid‐PI initiator under Mn2(CO)10 and visible light radiation at room temperature to efficiently prepare LPCs. The 1H‐NMR results revealed that the diacylglycerol moiety resided at the terminal position of the LPCs molecular chain. Through dynamic light scattering and transmission electron microscopy techniques, it was found that the Lipid‐POF (POF is defined as poly(OEGMA‐co‐FluMA)) prepared from OEGMA monomers can self‐assemble into spherical micelles with a particle size of approximately 80 nm in pure water. Furthermore, the in vitro bioassay results illustrate that the prepared Lipid‐POF not only can successfully modify the L929 cell surface but also has good biocompatibility. Overall, this study not only provides a fast and efficient method for synthesizing LPCs but also has broad application potential in the biomedical field. [ABSTRACT FROM AUTHOR]

AIM: To investigate the therapeutic efficacy of curcumin (Cur)-loaded engineered cell membrane mimetic nanoparticles (PD1-Cur@PLGA NPs) in treating breast cancer in mice, and to explore their tumor immunomodulatory effects. METHODS: Engineered mouse breast cancer 4T1-PD1 cell line expressing programmed death 1 (PD1) was established, and PD1 expression level was analyzed by flow cytometry. The 4T1-PD1 cell membranes were extracted and coated on the surface of Cur-loaded poly(lactic-co-glycolic) acid (PLGA) nanoparticles (Cur@PLGA NPs) using ice bath sonication to obtain PD1-Cur@PLGA NPs. The Cur loaded in various NPs was detected using UV-visible spectrophotometry. Particle size and morphology were analyzed by using dynamic light scattering and transmission electron microscopy. The 4T1 cells were divided into negative control (PLGA NPs and PD1-NVs), experimental (PD1-Cur@PLGA NPs), parallel control (Cur@PLGA NPs, and positive control (Cur) groups. In each group, cell viability was assessed by CCK-8 assay, and cell apoptosis was determined through flow cytometry. To perform treatment experiments in vivo, 4T1 cell-bearing tumor mice were randomly divided into PBS, PD1-NVs, and PD1-Cur@PLGA NPs groups. At the end of treatments, tissues of major organs were stained to detect pathological changes, as well as indicators of tumor proliferation (Ki67), apoptosis (TUNEL), and infiltration and activity of T cells (CD4+ and CD8+) in tumor tissues. RESULTS: The PD1 expression in 4T1-PD1 cell lines reached 78%. PD1-Cur@PLGA NPs exhibited a core-shell structure with particle sizes ranging from 100 to 200 nm. PD1-Cur@PLGA NPs enhanced the biocompatibility compared to free Cur and exhibited a strong apoptosis-inducing effect on 4T1 cells. Compared with control group, PD1-Cur@PLGA NPs significantly inhibited 4T1 breast tumor growth in vivo (P<0. 01), without apparent toxic side effects. Treatment with PD1-Cur@PLGA NPs reduced Ki67 expression, increased cell apoptosis, and enhanced infiltration and activity of CD4+ and CD8+ T cells in tumor tissues. CONCLUSION: PD1-Cur@PLGA NPs enhanced Cur biocompatibility and exhibited cytotoxicity against mouse breast cancer cells. This nanoformulation demonstrated promising therapeutic efficacy and safety in vivo, exerting potential antitumor immune regulatory effects. [ABSTRACT FROM AUTHOR]

In this letter, we demonstrate the successful development of graphene Schottky barrier diodes (Gr SBDs), which act as an efficient semi-transparent contact to n-GaN. We show that Gr SBDs can be used for deep trap investigations in n-GaN by capacitance-based spectroscopic techniques. To demonstrate its functionality, Gr Schottky barrier diodes on an n-GaN sample grown by the metal organic vapor phase technique were fabricated and then used in the measurements of steady-state photo-capacitance (SSPC) and deep level optical spectroscopy (DLOS). It is shown that the SSPC and DLOS spectra obtained for Gr SBDs are in excellent agreement with Ni-based semi-transparent contacts to n-GaN used in this study for comparison. Deep trap levels located at Ec-3.3 eV, Ec-2.6 eV, and Ec-1.84 eV for Ni SBD and Ec-3.3 eV and Ec-2.6 eV for Gr SBD were found, respectively. The presence of a trap level with Ec-1.84 eV observed only in the Ni SBD samples suggests that this trap originates from different sample treatments prior to Schottky contact deposition. Additionally, the optical capture cross-section data (σ0) derived from DLOS were fitted using the Lucovsky model under the assumption of no lattice relaxation for all deep traps observed in this study. Discrepancies in trap concentration derived from SSPC measurements among different diodes for a trap with EC-3.3 eV were attributed to reduced light transmission through the Gr contact in the UV spectral range and the presence of some macroscopic defects related to Gr transfer to the n-GaN film. [ABSTRACT FROM AUTHOR]

In order to meet the high uniformity calibration requirements for scientific-grade, large-size space detectors used in the CHES Extrasolar Planet Exploration Mission, this paper presents the design of a wide dynamic range, high uniformity spectral irradiance source (WHUIS). Utilizing a cascade integrating sphere design, and optimizing the overlapping area radiant flux adjustment structure and illumination light path, we achieve a wide dynamic range and high uniformity irradiance output. We established an irradiance transmission model based on the new assumption and analyzed the influence of factors such as illumination distance, stray light, and non-uniform radiance on the uniformity of irradiance output. The model is then validated by building experimental equipment. The findings show that in a circular area of 40 mm, the irradiance uniformity of our light source system exceeds 99.9%, and constant color temperature is adjustable within six orders of magnitude, consistent with the uniformity level predicted by the model. [ABSTRACT FROM AUTHOR]

Oligothiophenes with specific photophysical properties and molecular organization are of great interest, since this class of materials are used in organic electronics and bioelectronics, as well as biosensing. Herein, 8 different pentameric oligothiophenes, denoted proteophenes, with different amino acid substitution patterns at distinct positions along the thiophene backbone were investigated. Spectroscopic and microscopic studies of the ligands revealed the formation of optically active self‐assembled materials under acidic or basic conditions. The distinct photophysical characteristics, including induced circular dichroism, as well as the supramolecular structures of the assemblies deduced from light scattering and transmission electron microscopy, were highly influenced by the positioning of distinct amino acid moieties along the thiophene backbone. Proteophenes functionalized with only glutamate residues or these functionalities in combination with hydrophobic valine moieties formed fibrillar structures with excellent chiroptical properties under acidic conditions. In addition, the amino acid functionality at the β‐position of distinct thiophene moieties influenced the induced circular dichroism pattern observed from the proteophenes. Overall, the obtained results demonstrate how changes in the position of various amino acid functionalities, as well as the chemical nature of the amino acid side chain functionality greatly affect the optical properties as well as the architecture of the self‐assembled materials. [ABSTRACT FROM AUTHOR]

Optical satellite networks (OSNs) play an important role in space applications since it has some merits such as high data rate and low power. Increasing space applications generate a large amount of data on satellite so that satellites have difficulty in downloading these data to ground station timely under the limited contact window. Thus, we investigate the problem of collaborative data downloading in this paper. The problem lies on how to energy-efficiently offload data by optical inter-satellite links (ISLs) to balance data load and downlink capacity of each satellite so as to improve the performance of data downloading in OSN. Firstly, we develop the Cost Time-evolving Graph (CTEG) to describe optical transmission cost and the time-varying topology of OSN. Secondly, the problem of collaborative data downloading is formulated as Multi-objective Mixed-integer Linear Programming (MOMILP) which is proven to be NP-hard. For reducing computational complexity, we divide the scheduling time into multiple stages and propose the Multi-stage Collaborative Scheduling Algorithm (MCSA) which operates on a slot-by-slot basis. Simulations are conducted in the joint platform and results demonstrate that, compared with CoDld and No-ISLs, the MCSA provides a relatively high data throughput meanwhile drastically reducing energy consumption generated by data offloading. [ABSTRACT FROM AUTHOR]

Electron beam techniques have been used to analyze the impact of substrate choice and growth parameters on the compositional and optical properties of tin gallium oxide [(SnxGa1−x)2O3] thin films grown by plasma‐assisted molecular beam epitaxy. Sn incorporation and film quality are found to be highly dependent on growth temperature and substrate material (silicon, sapphire, and bulk Ga2O3) with alloy concentrations varying up to an x value of 0.11. Room temperature cathodoluminescence spectra show the Sn alloying suppressing UV (3.3–3.0 eV), enhancing blue (2.8–2.4 eV), and generating green (2.4–2.0 eV) emission, indicative of the introduction of a high density of gallium vacancies (VGa) and subsequent VGa–Sn complexes. This behavior was further analyzed by mapping composition and luminescence across a cross section. Compared to Ga2O3, the spectral bands show a clear redshift due to bandgap reduction, confirmed by optical transmission measurements. The results show promise that the bandgap of gallium oxide can successfully be reduced through Sn alloying and used for bandgap engineering within UV optoelectronic devices. [ABSTRACT FROM AUTHOR]

The nonlinear Schrödinger equation is one of the most important physical model in optical fiber theory for comprehension of the fluctuations of optical bullet development. In this study, the exact bullet solutions for the (3+1)-dimensional Schrödinger equation which demonstrate the bullet behaviours in optical fibers can be accumulated through the Sardar sub-equation method and the unified method. The applied strategies may retrieve several kinds of optical bullet solutions within one frameworks as well as is quite simple and reliable. Mathematica are utilised for describing the dynamics of different wave structures as 3D, 2D, and contour visualisations for a given set of parameters. As a result, we are able to develop a variety of travelling wave structures namely the periodic, singular and V shaped soliton wave solutions. The stability analysis for the derived results is analysed efficiently while the modulation instability for the governing model has also been studied to demonstrate the reliability of the research. The approaches implemented here works perfectly and can be extended to deal with many advanced models in contemporary areas of science and engineering. The solutions attain by using these techniques are robust, unique and straight forward and has applications in different fields of physics, engineering and mathematical science. Specially physical applications of these obtain results are in the transmission of data in optical fibers. We also add the graphics for the better understanding of the attain solutions behaviour. [ABSTRACT FROM AUTHOR]

In this article, the modified extended Fan sub-equation approach as an analytical tool to investigate the optical soliton solutions of the paraxial wave dynamical model with Kerr media. Indistinguishable and non-diffractive spatially scattered waves transmitting in the optical Kerr medium are explained by optical solitary waves. The solitons, single and mixed non-degenerate Jacobi elliptic function type solutions of the time-dependent dimensionless paraxial wave equation are assembled using the modified extended Fan sub-equation approach. The aforementioned approach offers new, comprehensive solutions that are relatively easy to implement, in contrast to earlier continuous strategies. This technique uses a traveling wave transformation to convert a non-linear partial differential equation into an ODE. The developed wave solutions have substantial significance in the fields of science and engineering. Visual illustrations of various soliton layouts can be achieved by supplying suitable values for the parameters via this technique. The computer software Mathematica 13.2 is used to illustrate several modulus, real, and imaginary solutions visually in the form of contour, 2D, and 3D visualizations that help understand the concrete importance of the paraxial wave dynamical model. The results are fascinating and can potentially be helpful in investigating the stochastic aspects of many nonlinear physical theories that arise in optical studies and a number of other scientific fields. [ABSTRACT FROM AUTHOR]

In recent years, the scientific community has spent significant effort exploring radiation-shielding glass materials. The present work was conducted by synthesizing a glass series of 20La2O–10BaO –15Na2O–(55−x)SiO2–xBi2O3, x: 0, 5, 15, and 25 wt%. After producing the samples, in-depth studies were performed on the physical, optical, thermal, and radiation attenuation properties of the fabricated glass series. A radical color change from nearly neutral to dark-brown color occurred as Bi2O3 entered the glass network. The density values equaled 2.8324, 2.9511, 3.0992, and 3.3657 g cm−3 for LBSS1 to LBSS4 samples, respectively. According to XRD patterns, neither sharp nor moderate peaks developed; a hump-like formation between 20 and 35 degrees was visible in all glass samples. FTIR measurement revealed transmission as a function of varying wavenumber from 4000 to 400 cm−1 for the prepared glass specimens, and different bond types were noted. The UV–Vis technique removes it displayed that increasing Bi2O3 content blocked light transmission throughout the glass medium. The radiation-shielding parameters of linear attenuation coefficient (LAC), mass attenuation coefficient, transmission factor, and half value layer were calculated with experimental and MC simulation methods for all glass samples at six different energies between 356 and 1332 keV. The results were compared with the Phy-X database, and good agreement was obtained. The highest LACs were obtained at the lowest energy (356 keV) with values of 0.3108, 0.3455, 0.4471, and 0.5486 cm−1 for LBSS1, LBSS2, LBSS3, and LBSS4 glasses, respectively. The photon attenuation ability of the LBSS glasses increased by increasing the Bi2O3 ratio, especially at low energies. Therefore, the authors can conclude that future applications, such as observation window in CT rooms, may efficiently exploit LBBS4 glass system. [ABSTRACT FROM AUTHOR]

Thermochromic smart windows have emerged as a focal point in energy research. In this study, a novel approach is introduced for developing thermoresponsive materials for smart windows, utilizing microscopic agglomeration of molecules to regulate incident light. The groundbreaking material, β‐CD‐Val‐IBAm4, is constructed by grafting four isobutylated valines onto natural β‐cyclodextrins. This material exhibits a unique “hand‐in‐hand” effect, resulting from the interaction of isobutylated valine side chains, which leads to molecular aggregation and reduced light transmission at elevated temperatures. The hydration–dehydration process is related to molecular aggregation rather than crosslinking, ensuring the structural integrity and uniformity of the smart windows. Molecular dynamics simulations and 2D NOESY confirm the thermal response mechanism of β‐CD‐Val‐IBAm4. When dissolve in a glycerol‐water binary solvent system, the material forms a thermochromic liquid with outstanding optical performance (ΔTsol of 1 mm liquid can reach 69.8%) and long‐term stability. This innovative approach opens new avenues for the advancement of next‐generation smart window technologies. [ABSTRACT FROM AUTHOR]

Development of restorative materials capable of mimicking optical and mechanical performance of natural teeth is a quest in aesthetic density. Yttria-Stabilized Zirconia (YSZ) ceramics represent one of the most popular choices for dental restorations, owing to their biocompatibility, white colour, and the possibility to use CAD-CAM technologies. In particular, YSZ doped with 3 mol. % yttria (3YSZ) is popular because it presents high strength. Nonetheless, the limited light transmission of commercially available high strength 3YSZ does not meet the requirements of highly aesthetic cases. On the other side, YSZ presenting a larger portion of yttria are more translucent but exhibit modest strength. Here, we report on fabrication of dense zirconia nanostructures in bulk form via conventional pressure-less sintering at temperatures down to 1100–1200 °C, achieving highly translucent and strong 3YSZ with significant opalescent behaviour. Both Hall−Petch and inverse Hall-Petch relationship were observed in 3YSZ samples with average grain size in the range of 250 nm and 55 nm, demonstrating the importance of grain size control to enhance both optical and mechanical properties of zirconia ceramics, simultaneously. Maximum biaxial strength of 1980 ± 260 MPa, in-line light transmission of 38% in the visible spectrum and opalescence approaching that of enamel were obtained at optimum grain size of 80 ± 5 nm. The notable optical properties are linked to the miniaturization of the residual pores and refinement of grain size towards the nanoscale while the superior mechanical strength is justified by the activation of different energy dissipation processes at nano and macroscale. [Display omitted] [ABSTRACT FROM AUTHOR]

The Schrödinger–Hirota equation is one of the most important models of contemporary physics which is popular throughout the broad fields of fluid movement as well as in the study of thick-water crests, liquid science, refractive optical components and so on. In this paper, we utilize the Hirota bilinear technique and the unified technique to attain various soliton solutions of the governing model analytically. These approaches are robust, powerful and unique also have many applications in different fields of mathematical physics. The solutions attained from these techniques are highly valuable and useful in various fields of sciences specially in the transmissions of optical fibers, also they give different behaviors including V-shaped and periodic soliton solution behavior. Further, the approaches applied here are not applied in this model previously. Therefore, ours is a new work, which summarizes its novelty. The 3D, 2D and contour plots are included to grasp the understanding of solutions' behavior. These findings are valuable in electronic communications such as elliptical circuits and in investigation of solitude controlling. [ABSTRACT FROM AUTHOR]

Glasses in the TeO2–Ga2O3–M2O (M═Li, Na, or K) systems were synthesized by a melt‐quenching technique. The glass forming areas were delimited for each system. Systematic analyses were performed on two series of samples—the first one with a constant TeO2/Ga2O3 ratio of 85/15, that is, [(TeO2)0.85(Ga2O3)0.15]100−x[M2O]x with 0 ≤ x ≤ 25 (with a step of 5 mol%), the second one with a constant alkaline oxide concentration of 10 mol%, that is, [TeO2]90‐y[Ga2O3]y[M2O]10 with 5 ≤ y ≤ 15 (with step of 2.5 mol%). The values of the glass transition temperature, density, and optical transmission parameters (the positions of short‐ and long‐wavelength absorption edge and the maximum transmittance value) were determined. The changes in these parameters were studied for varying glass compositions. In addition, the values of refractive index were measured at various wavelengths across the whole transparency region reaching from the visible up to the mid‐infrared range. [ABSTRACT FROM AUTHOR]

Background: Despite combined anticoagulation therapy consisting of a vitamin K antagonist and an antiplatelet agent, thromboembolic complications often occur in patients with a left ventricular assist device (LVAD). In addition, bleeding events are also common. Resistance to antiplatelet drugs is a well‐known phenomenon; however, the utilization of laboratory chemistry testing for the presence of such resistance, and then switching therapy, is controversial. Methods: We tested 132 patients with LVAD (HeartWare n = 57, HeartMate II n = 22, HeartMate 3 n = 53) on acetylsalicylic acid (ASA) therapy for resistance and followed them for a maximum of 7 years regarding pump thrombosis. Light transmission aggregometry (LTA) and impedance aggregometry (IPA) were performed for testing platelet function. Results: We could show that patients with ASA resistance displayed an increased risk of pump thrombosis, regardless of the test used (LTA: OR = 6.20, CI [1.86–20.64], p = 0.003; IPA: OR = 12.14, CI [3.00–49.07], p < 0.001). In patients with a HeartMate 3, we could not detect any pump thrombosis associated with aspirin resistance. Furthermore, there was no significant difference in bleeding events between patients with ASA resistance and ASA responders. Conclusion: Laboratory testing of ASA resistance seems to be a good tool to detect an increased risk of pump thrombosis, at least for patients with a HeartWare or HeartMate II. The extent to which these thromboses can be prevented with a change of medication has to be investigated in further studies. No pump thrombosis was detected in patients with a HeartMate 3, and the question should be asked as to what constellation of underlying and concomitant diseases must be present to justify ASA therapy for these patients. [ABSTRACT FROM AUTHOR]

In this paper, we propose a low-complexity fiber nonlinearity impairments compensation scheme based on nonlinear step size and modified adaptive digital back propagation. To verify the feasibility of the proposed algorithm, we construct a simulation system of single channel 12.5 GBaud polarization division multiplexing 16-ary quadrature amplitude modulation (PDM-16QAM) optical transmission system. Comprehensive numerical simulation results demonstrate that the proposed scheme can not only search for the fiber nonlinear coefficient adaptively, but also has the characteristics of high performance and low complexity. [ABSTRACT FROM AUTHOR]

In this paper, we study a dual hop hybrid radio frequency-visible light communication (RF-VLC) system with wireless energy harvesting technique. In the proposed model the RF channel and the VLC channel are modelled by generalized-K distribution and lambertian emission model, respectively. A decode and forward relay is used as an intermediate node where power splitting relaying (PSR) protocol is employed to harvest energy from the received RF information signal. The source transmits the information signal towards the relay via RF channel. The relay then decodes the received signal and convert it into corresponding light signal. Simultaneously the energy harvesting circuit at relay harvests the energy from the received RF signal. The relay utilizes the harvested energy to aid the transmission of the light signal towards the user situated inside the building's room at the destination. Further, the statistics of the instantaneous SNR of the hybrid RF-VLC system at the destination are derived by employing the PSR protocol to obtain an accurate closed form analytical expression for the system's end-to-end ergodic capacity and achievable throughput in terms of Meijer's G function. Further, with the help of numerical simulations, we analysed the end-to-end ergodic throughput performance of the hybrid system under the influence of varying channel parameters such as signal to noise ratio, power splitting factor, shadowing parameters, distance between source & relay and source transmitted power. [ABSTRACT FROM AUTHOR]

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With the rapid development and commercial interest in the organ-on-a-chip (OoC) field, there is a need for materials addressing key experimental demands and enabling both prototyping and large-scale production. Here, we utilized the gas-permeable, thermoplastic material polymethylpentene (PMP). Three methods were tested to prototype transparent PMP films suitable for transmission light microscopy: hot-press molding, extrusion, and polishing of a commercial, hazy extruded film. The transparent films (thickness 20, 125, 133, 356, and 653 µm) were assembled as the cell-adhering layer in sealed culture chamber devices, to assess resulting oxygen concentration after 4 days of A549 cell culture (cancerous lung epithelial cells). Oxygen concentrations stabilized between 15.6% and 11.6%, where the thicker the film, the lower the oxygen concentration. Cell adherence, proliferation, and viability were comparable to glass for all PMP films (coated with poly-L-lysine), and transparency was adequate for transmission light microscopy of adherent cells. Hot-press molding was concluded as the preferred film prototyping method, due to excellent and reproducible film transparency, the possibility to easily vary film thickness, and the equipment being commonly available. The molecular orientation in the PMP films was characterized by IR dichroism. As expected, the extruded films showed clear orientation, but a novel result was that hot-press molding may also induce some orientation. It has been reported that orientation affects the permeability, but with the films in this study, we conclude that the orientation is not a critical factor. With the obtained results, we find it likely that OoC models with relevant in vivo oxygen concentrations may be facilitated by PMP. Combined with established large-scale production methods for thermoplastics, we foresee a useful role for PMP within the OoC field. [ABSTRACT FROM AUTHOR]

Featured Application: Featured Application: The results presented inform a parametric wavelength at which photobiomodulation therapy of spinal cord injury could be most viable for clinical testing. This study compared the transcutaneous target level irradiances from the thoracic to lumbar segments of the interior spinal canal in three cadaver dogs, measured for light at four wavelengths (808 nm, 915 nm, 975 nm, and 1064 nm), common in photobiomodulation therapy (PBMT). Intra-spinal irradiances at nine sites spanning approximately 8 cm in length were measured using a flexible intra-spinal probe under surface application of continuous-wave (CW) light with powers ranging from 0.5 W to 2 W. Surface illumination was applied using an acupuncture treatment head in three modes: non-contact with skin removed, non-contact with skin intact, and contact with skin intact. During surface application, the treatment head was positioned over the spinal canal near the 13th vertebrae (T13, surface site 1), and approximately 4 cm (surface site 5) and 8 cm (surface site 9) caudal to T13. At each position of the treatment head, the light was multiplexed among the four wavelengths at the same power setting. In all three modes of surface application, the target level irradiance at the 1064 nm wavelength was significantly greater than that at the other three wavelengths (p ≤ 0.0017). At a surface irradiance of ~157 mW/cm2, corresponding to 0.5 W light applied with the treatment head directly in contact with the skin, the intra-spinal irradiance at 1064 nm reached 0.137 ± 0.095 mW/cm2. Obtaining a dosage of PBMT-associative wavelengths of this magnitude at the level of the spinal canal may guide focused research into the transcutaneous applicability of PBMT for spinal cord injuries. [ABSTRACT FROM AUTHOR]