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Metaphotonic devices, which enable light manipulation at a subwavelength scale and enhance light–matter interactions, have been emerging as a critical pillar in biosensing. Researchers have been attracted to metaphotonic biosensors, as they solve the limitations of the existing bioanalytical techniques, including the sensitivity, selectivity, and detection limit. Here, we briefly introduce types of metasurfaces utilized in various metaphotonic biomolecular sensing domains such as refractometry, surface-enhanced fluorescence, vibrational spectroscopy, and chiral sensing. Further, we list the prevalent working mechanisms of those metaphotonic bio-detection schemes. Furthermore, we summarize the recent progress in chip integration for metaphotonic biosensing to enable innovative point-of-care devices in healthcare. Finally, we discuss the impediments in metaphotonic biosensing, such as its cost effectiveness and treatment for intricate biospecimens, and present a prospect for potential directions for materializing these device strategies, significantly influencing clinical diagnostics in health and safety. [ABSTRACT FROM AUTHOR]

The manuscript presents the tunable excitation characteristics of an optical Tamm state (OTS). The tunability is obtained by integrating a functional organic crystal DAST (4-N,N-dimethylamino-4′-N′-methyl-stilbazolium tosylate) material with conventional one-dimensional photonic crystal (1D-PhC) structure. The DAST layer is deliberately introduced at the top of the structure to excite a plasmonic-like mode called OTS. The device structure is thoroughly optimized to excite the OTS at a 632.8 nm operating wavelength. The OTS excitation is analyzed analytically by angular interrogation, wavelength interrogation methods, and electrical field distribution interrogation. The dispersion analysis exhibits a strong excitation of OTS at the top interface when a polychromatic light is incident at a 45.11° incidence angle. This demonstrates a post-fabrication 47 nm dynamic wavelength tuning of excited Tamm mode by applying a ± 5 V bias voltage. Additionally, the Tamm mode response is very stable, which requires only a 5.7° variation in incidence angle to excite the Tamm at a constant 632.8 nm operating wavelength for the corresponding bias voltage variation of ± 5 V. This shows its potential applications in tunable stable optical sensors, dynamic color filtering and displays, and short focal length tuning compact imagers. This novel integration of organic electro-optical material with 1D-PhC will enhance its applicability in future tunable optical devices. [ABSTRACT FROM AUTHOR]

In this paper, a Janus metastructure sensor (JMS) based on the photonic spin Hall effect (PSHE), which can detect multiple physical quantities, is proposed. The Janus property is derived from the fact that the asymmetric arrangement of different dielectrics breaks the structure parity. Hence, the metastructure is endowed with different detection performances for physical quantities on multiple scales, broadening the range and improving the accuracy of the detection. When electromagnetic waves (EWs) are incident from the forward scale of the JMS, the refractive index, thickness, and incidence angle can be detected by locking the angle corresponding to the PSHE displacement peak that is enhanced by the graphene. The relevant detection ranges are 2~2.4, 2~2.35 μm, and 27°~47°, with sensitivities (S) of 81.35°/RIU, 64.84°/μm, and 0.02238 THz/°, respectively. Under the condition that EWs incident into the JMS from the backward direction, the JMS can also detect the same physical quantities with different sensing properties, such as S of 99.3°/RIU, 70.07°/μm, and 0.02348 THz/° in corresponding detection ranges of 2~2.09, 1.85~2.02 μm, and 20°~40°. This novel multifunctional JMS is a supplement to the traditional single-function sensor and has a certain prospect in the field of multiscenario applications. [ABSTRACT FROM AUTHOR]

Molecular vibrations play a crucial role in physical chemistry and biochemistry, and Raman and infrared spectroscopy are the two most used techniques for vibrational spectroscopy. These techniques provide unique fingerprints of the molecules in a sample, which can be used to identify the chemical bonds, functional groups, and structures of the molecules. In this review article, recent research and development activities for molecular fingerprint detection using Raman and infrared spectroscopy are discussed, with a focus on identifying specific biomolecules and studying the chemical composition of biological samples for cancer diagnosis applications. The working principle and instrumentation of each technique are also discussed for a better understanding of the analytical versatility of vibrational spectroscopy. Raman spectroscopy is an invaluable tool for studying molecules and their interactions, and its use is likely to continue to grow in the future. Research has demonstrated that Raman spectroscopy is capable of accurately diagnosing various types of cancer, making it a valuable alternative to traditional diagnostic methods such as endoscopy. Infrared spectroscopy can provide complementary information to Raman spectroscopy and detect a wide range of biomolecules at low concentrations, even in complex biological samples. The article concludes with a comparison of the techniques and insights into future directions. [ABSTRACT FROM AUTHOR]

Realizing rapid and stable hydrogen sorption at low temperature is critical for magnesium-based hydrogen storage materials. Herein, liquid channels are built in magnesium hydride by introducing lithium borohydride ion conductors as an efficient route for improving its hydrogen sorption. For instance, the 5 wt% LiBH4-doped MgH2 can release about 7.1 wt.% H2 within 40 min at 300 °C but pure MgH2 only desorbs less than 0.7 wt.% H2, and more importantly it delivers faster desorption kinetics with more than 10 times enhancement to pure MgH2. The hydrogen absorption capacity of LiBH4-doped MgH2 can still be well kept at approximately 7.2 wt.% without obvious capacity degradation even after six absorption and desorption cycles. This approach is not only through building ion transfer channels as a hydrogen carrier for kinetic enhancement but also by inhibiting the agglomeration of MgH2 particles to obtain stable cyclic performance, which brings further insights to promoting the hydrogen ab-/desorption of other metal hydrides. [ABSTRACT FROM AUTHOR]

In this study, a novel narrowband perfect absorber (NPA) with dual band resonance frequencies is presented. The proposed NPA absorbs over 99% of the incident laser beam in both resonance modes and it indicates high quality factor (Q = 135.2) resonance which is the highest for a perfect absorber performing in the mid-infrared region. In this work, the charge and current distributions for the corresponding resonance modes are investigated. The absorbance spectrum of the electric and magnetic field distributions is also obtained for the corresponding resonance modes. Furthermore, the detecting performance of the NPA is analyzed by covering the proposed device with a cladding layer. The figure of merit (FOM) and refractive index sensitivity (RIS) of the structure are calculated. Due to its high quality factor, enhanced electric and magnetic field responses, near unity absorbance for both resonance modes and tunable detecting characteristics the proposed NPA can be used in spectroscopy applications. [ABSTRACT FROM AUTHOR]

The dielectric metasurface has become a powerful tool for compact optical components with various wavefront controlling functionalities accompanied by negligible losses at the corresponding working frequencies. In this work, we propose a tunable all-dielectric metasurface as an optical filter with high resolution covering different optical communication bands, where tunability is realized by a combination of changing the incident angle and modulating the refractive index of an optical phase changing material (OPCM). When the incident angle varies, our optical filter based on a two-dimensional bound state in continuums (BIC) metasurface can achieve sequential, extremely sharp resonances. In addition, the resonance peaks could be further shifted to a different frequency band by the refractive index change of OPCM via pulsed laser heating. The proposed scheme can offer optical filters with high spectral resolution and large tunable working wavelength range, which greatly benefits from the topological property of BIC and large modulation depth of OPCM. [ABSTRACT FROM AUTHOR]

Nanorings (NRs) with their intrinsic cavities have attracted interest as plasmonic nanoparticles for years, due to the uniform electric field enhancement inside the cavity, lower plasmon damping effects and comparatively high refractive index sensitivities. In the present work, we successfully fabricated a series of Au NR arrays on flexible polydimethylsiloxane substrates by taking advantage of state-of-the-art fabrication methods such as electron beam lithography and wet-etching transfer techniques. In-situ optical measurements on these flexible systems are enabled by implementing a homemade micro-stretcher inside an optical reflection spectroscopy setup. The corresponding dark-field spectra of thin-walled NR arrays exhibit a strong shift to longer wavelengths (i.e., ~ 2.85 nm per 1% strain) under polarization perpendicular to the traction, mainly resulting from the increasing shape deformation of the NRs under strain. Moreover, numerical simulations illustrate that the shifting plasmonic mode has a radially-symmetric charge distribution of the bonding mode and is rather sensitive to the tuning of the NRs' shape as confirmed by a subsequent in-situ scanning electron microscope characterization. These results explore the possibilities of shape-altering flexible plasmonics for nanoparticles with a cavity and indicate potential applications for plasmonic colors and biochemical sensing in future work. [ABSTRACT FROM AUTHOR]

Seebeck measurements of n-type amorphous germanium telluride thin films (100 nm) containing oxygen and implanted with Bismuth (Bi) have been studied under dark and monochromatic light conditions from 1800 to 400 nm. The Bi-doped film has a negative Seebeck coefficient indicating its n-type nature that results from the implantation compared to the p-type undoped films. Upon illumination with monochromatic light across the near-infrared and visible region the magnitude of the measured Seebeck voltage increases (becomes more negative). This increase in Seebeck coefficient displays distinctive behaviours in different spectral regions and is caused by the inclusion of Bi ions as foreign impurities. Furthermore, the Seebeck coefficients are used to determine the film electrical properties and enable, along with complementary characterisation including X-ray photoelectron spectroscopy, electronic band diagrams to be proposed for before and after Bi ion implantation. The photo-Seebeck technique is utilised for the first time to probe the trap states created due to the implantation, providing an understanding of the mechanisms behind non-equilibrium carrier-type reversal in an amorphous system, including the modification of electronic and optoelectronic properties such as the optical bandgap. [ABSTRACT FROM AUTHOR]

The generation of single photons in the mid-infrared spectral region is attracting the interest of scientific and technological research, motivated by the potential improvements that many important and emerging applications, such as quantum sensing, metrology and communication, could benefit from. This review reports the progress in short and mid-infrared single photon generation, focusing on probabilistic sources based on the two non-linear processes of spontaneous parametric downconversion (SPDC) and four wave mixing (FWM). On one hand, numerical simulations of mid-infrared SPDC are described as a powerful tool to assist and guide the experimental realization, along with the implementation and engineering of novel non-linear materials. On the other hand, the advantages offered by FWM in silicon waveguides in terms of integration, miniaturization and manufacturability are presented, providing an optimal technology for integrated quantum applications. [ABSTRACT FROM AUTHOR]

A MIMI (metal–insulator-metal–insulator) nanoparticle was conceived and synthesized. It consists of a core of gold nanoparticles of different shapes, covered by a silica shell in turn covered by a layer of gold and finally by another silica shell. This hybrid nano-matryoshka, completely dispersed in water, was characterized by UV–Vis and TEM spectroscopy, comparing the architecture and photophysical properties of each synthetic step. Through a numerical simulation, it was possible to study in depth the absorption and extinction cross sections, determining the role of the various layers. This is an example of architecture used in the construction of metamaterials, the first in the form of a water-dispersed nanoparticles. [ABSTRACT FROM AUTHOR]

Phase-change materials, demonstrating a rapid switching between two distinct states with a sharp contrast in electrical, optical or magnetic properties, are vital for modern photonic and electronic devices. To date, this effect is observed in chalcogenide compounds based on Se, Te or both, and most recently in stoichiometric Sb2S3 composition. Yet, to achieve best integrability into modern photonics and electronics, the mixed S/Se/Te phase change medium is needed, which would allow a wide tuning range for such important physical properties as vitreous phase stability, radiation and photo-sensitivity, optical gap, electrical and thermal conductivity, non-linear optical effects, as well as the possibility of structural modification at nanoscale. In this work, a thermally-induced high-to-low resistivity switching below 200 °C is demonstrated in Sb-rich equichalcogenides (containing S, Se and Te in equal proportions). The nanoscale mechanism is associated with interchange between tetrahedral and octahedral coordination of Ge and Sb atoms, substitution of Te in the nearest Ge environment by S or Se, and Sb–Ge/Sb bonds formation upon further annealing. The material can be integrated into chalcogenide-based multifunctional platforms, neuromorphic computational systems, photonic devices and sensors. [ABSTRACT FROM AUTHOR]

Plasmonic effects that enhance electric fields and amplify optical signals are crucial for improving the resolution of optical imaging systems. In this paper, a metal-based plasmonic nanostructure (MPN) is designed to increase the resolution of an optical imaging system by amplifying a specific signal while producing a plasmonic effect via a dipole nanoantenna (DN) and grating nanostructure (GN), which couple the electric field to be focused at the center of the unit cell. We confirmed that the MPN enhances electric fields 15 times more than the DN and GN, enabling the acquisition of finely resolved optical signals. The experiments confirmed that compared with the initial laser intensity, the MPN, which was fabricated by nanoimprint lithography, enhanced the optical signal of the laser by 2.24 times. Moreover, when the MPN was applied in two optical imaging systems, an indistinguishable signal that was similar to noise in original was distinguished by amplifying the optical signal as 106 times in functional near-infrared spectroscopy(fNIRS), and a specific wavelength was enhanced in fluorescence image. Thus, the incorporation of this nanostructure increased the utility of the collected data and could enhance optical signals in optics, bioimaging, and biology applications. [ABSTRACT FROM AUTHOR]

Visual cryptography is a potentially important technique for optical information security. However, the limitations of carrier materials and the high precision requirements of the reconstruction process limit the application scope of visual cryptography. Herein, we propose a novel visual cryptography technique based on ghost imaging. The spatial information on one visual key image is encoded into time-varying factors in ghost imaging and loaded onto Hadamard illumination patterns. The secret image can be recovered when the illumination patterns are projected onto another visual key image. This method utilizes light-intensity superposition to overlap visual key image pixels. Simulation and experimental results substantiate the feasibility and security of the proposed technique. This method incorporates the unique advantages of ghost imaging and visual cryptography and is not limited by carrier materials and precision. Hence, it has high scalability and broad application scenarios in ghost imaging broadcasting systems and information authentication, among others. [ABSTRACT FROM AUTHOR]

Four-corner fusion (4CF) is a known treatment option for degenerative wrist conditions. Different techniques may be used and there is no general consensus on best implant. As such, it was the purpose of the current systematic review to compare fusion rates and outcomes depending on the fixation technique. The systematic review was registered in the international prospective register of systematic reviews (PROSPERO): CRD42020164301. It followed the PRISMA guidelines. Original articles were screened using the following databases: Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE and Web of Science Core Collection. Studies reporting on outcome for 4CF surgery were included. Studies with a minimum Level IV of evidence were considered eligible. Quality assessment was performed using the Methodological Index for Non-Randomized Studies (MINORS) criteria. A total of 29 studies met the inclusion criteria, for a total of 1103 wrists. The mean age was 41.8 years (range 19–83). Mean follow-up overall was 43.5 months (range 24–146 months). Reported fusion weighted rates were >90% and did not differ significantly between techniques. Reoperations due to different reasons occurred in 135 (12%) of all 1103. There was significant data heterogeneity regarding fusion rates (I2 = 70%). Inconsistency and heterogeneity in data reporting did not allow meta-analysis with direct data pooling and comparison of subgroups. Satisfactory fusion rates (over 90%) can be achieved independent of the fixation technique used in 4-corner arthrodesis. Due to the high data heterogeneity and reporting inconsistency across studies, no statements regarding PROMs, ROM or grip strength can be made. Systematic Review of Level IV Studies. [ABSTRACT FROM AUTHOR]

Vibrational spectroscopic techniques, namely Fourier transform infrared (FTIR) and Raman spectroscopy, are based on the study of molecular vibrations, and they are complementary techniques to each other. This review provides an overview of the vibrational spectroscopic techniques applied in microbiology during the past decade. In addition, future applications of the elaborated spectroscopic techniques will be highlighted. The results of this review show that both FTIR and Raman spectroscopy are promising alternatives to conventional diagnostic approaches because they provide label-free and noninvasive bacterial detection, identification, and antibiotic susceptibility testing in a single step. Cost-effective, accurate, and rapid tests are needed in order to improve diagnostics and patient care, to decrease the use of unnecessary antimicrobial agents, to prevent resistant microbials, and to decrease the overall burden of outbreaks. Prior to that, however, the presented approaches need to be validated in a clinical workflow against the conventional diagnostic approaches. [ABSTRACT FROM AUTHOR]

Optical sensing technologies for hydrogen monitoring are of increasing importance in connection with the development and expanded use of hydrogen and for transition to the hydrogen economy. The past decades have witnessed a rapid development of optical sensors for hydrogen monitoring due to their excellent features of being immune to electromagnetic interference, highly sensitive, and widely applicable to a broad range of applications including gas sensing at the sub-ppm range. However, the selection of hydrogen selective metal and metal alloy plays an important role. Considering the major advancements in the field of optical sensing technologies, this review aims to provide an overview of the recent progress in hydrogen monitoring. Additionally, this review highlights the sensing principles, advantages, limitations, and future development. [ABSTRACT FROM AUTHOR]

Plasmonic hydrogen gas sensors have become widely used in recent years due to their low cost, reliability, safety, and measurement accuracy. In this paper, we designed, optimized, and fabricated a palladium (Pd)-coated nano-grating-based plasmonic hydrogen gas sensor; and investigated using the finite-difference time-domain method and experimental spectral reflectance measurements, the calibrated effects of hydrogen gas exposure on the mechano-optical properties of the Pd sensing layer. The nanostructures were fabricated using DC sputter deposition onto a one-dimensional nano-grating optimized with a thin-film gold buffer to extend the optical response dynamic range and performance stability; the color change sensitivity of the Pd surface layer was demonstrated for hydrogen gas concentrations as low as 0.5 vol.%, up to 4 vol.%, based on the resonance wavelength shift within the visible band corresponding to the reversible phase transformation. Visual color change detection of even the smallest hydrogen concentrations indicated the high sensitivity of the gas sensor. Our technique has potential for application to high-accuracy portable plasmonic sensors compatible with biochemical sensing with smartphones. [ABSTRACT FROM AUTHOR]

We report on solving of two intriguing issues concerning the inscription of surface relief gratings within azopolymer thin films under irradiation with SS, PP and RL interference patterns. For this, we utilize the orientation approach and viscoplastic modeling in combination with experimental results, where the change in surface topography is acquired in situ during irradiation with modulated light. First, the initial orientation state of polymer backbones is proved to be responsible for the contradictory experimental reports on the efficiency of the SS interference pattern. Different orientation states can influence not only the phase of SS grating but also its height, which is experimentally confirmed by using special pretreatments. Second, the faster growth of gratings inscribed by the RL interference pattern is shown to be promoted by a weak photosoftening effect. Overall, the modeled results are in good agreement with the order of relative growth efficiency: RL–PP–SS. [ABSTRACT FROM AUTHOR]

Traumatic neuromas are infrequent in clinical settings but are prevalent following trauma or surgery. A traumatic neuroma is not a true malignancy, rather, it is a hyperplastic, reparative nerve reaction after injury and typically manifests as a nodular mass. The most common clinical manifestations include painful hypersensitivity and the presence of a trigger point that causes neuralgic pain, which could seriously decrease the living standards of patients. While various studies are conducted aiming to improve current diagnosis and management strategies via the induction of emerging imaging tools and surgical or conservative treatment. However, researchers and clinicians have yet to reach a consensus regarding traumatic neuromas. In this review, we aim to start with the possible underlying mechanisms of traumatic neuromas, elaborate on the diagnosis, treatment, and prevention schemes, and discuss the current experiment models and advances in research for the future management of traumatic neuromas. [ABSTRACT FROM AUTHOR]

Background: Ulnar-sided wrist pain is associated with the development of multiple wrist pathologies. But the anatomical etiologies have not been fully understood. Purpose: To determine the association of three anatomical factors with ulnar-sided wrist pain, including ulnar variance (UV), distal ulnar volar angle (DUVA), and pisiform-ulnar distance (PUD). Material and Methods: A total of 64 patients who had ulnar-sided wrist pain associated with training injuries were retrospectively studied. A control group included 64 healthy athletes from the same unit. The UV, DUVA, and PUD of each individual was measured on radiographs. Results: The average UV and DUVA of those in the ulnar-sided pain group were 0.84 mm and 174.65°, respectively; the control group values were 0.39 mm and 175.11°. The differences between the two groups had no statistical significance (P > 0.05). The average PUD of the ulnar-sided wrist pain group was shorter than that of the control group (2.37 cm vs. 2.65 cm); the difference had statistical significance (P < 0.05). PUD had a negative correlation with ulnar-sided pain; it was an anatomical protective factor (odds ratio = 0.01; P < 0.00; 95% confidence interval=0.00–0.05). Both UV and DUVA had no significant correlations with ulnar-sided wrist pain (P > 0.05). Conclusion: PUD has a significant correlation with ulnar-sided wrist pain. It is the anatomical protective factor. Both the UV and DUVA have no statistical association with ulnar-sided wrist pain, but we cannot ignore their potential pathogenic effects on wrists, and further studies are needed to confirm the results. [ABSTRACT FROM AUTHOR]

Structural colors resulting from nanostructured metallic surfaces hold a series of advantages compared to conventional chemical pigments and dyes, such as enhanced durability, tunability, scalability, and low consumption, making them particularly promising for preparing color-tunable devices. However, once these structures are fabricated, they are almost all passive devices with static nanostructures and fixed optical properties, limiting their potential applications. Here, by using a specially designed array of ordered SiO2 nanoholes as a deposition template in conjunction with the traditional reversible metal electrodeposition device (RMED), we propose a tunable reflective surface where the color of the surface can be changed as a function of the thickness of the deposited Ag nanoparticles (AgNPs). Simplified manufacturability and a large range of color tunability are achieved over previous reports by utilizing the SiO2 nanohole template, which allows the direct deposition of AgNPs while forming an array structure of Ag nanocylinders. Besides, a further thematic analysis of the physical mechanism in the proposed structure is conducted. The results show that the structural colors induced by the longitudinal localized surface plasmon resonance (LSPR) mode can be dynamically tuned from brown to purple via increasing the deposition thickness. Additionally, in combination with SiO2 nanohole templates of varying parameters, a full gamut of colors spanning the entire visible spectrum is achieved, revealing the feasibility of utilizing the properties of the LSPR mode for satisfying various color requirements. We believe that this LSPR-based multicolor RMED design will contribute to the development of full color information displays and light-modulating devices. [ABSTRACT FROM AUTHOR]

Display and power supply have been two essential and independent cornerstones of modern electronics. Here, we report a lithium-plasmon-based low-powered dynamic color display with intrinsic dual functionality (plasmonic display and energy recycling unit) which is a result of the electric-field-driven transformation of nanostructured lithium metals. Dynamic color displays are enabled by plasmonic transformation through electrodeposition (electrostripping) of lithium metals during the charging (discharging) process, while the consumed energy for coloring can be retrieved in the inverse process respectively. Energy recycling of lithium metals brings energy consumption down to 0.390 mW cm−2 (0.105 mW cm−2) for the active (static) coloration state of a proof-of-concept display/battery device, which approaches nearly-zero-energy-consumption in the near-100%-energy-efficiency limit of commercial lithium batteries. Combining the subwavelength feature of plasmonics with effective energy recycling, the lithium-plasmon-based dynamic display offers a promising route towards next-generation integrated photonic devices, with the intriguing advantages of low energy consumption, a small footprint and high resolution. [ABSTRACT FROM AUTHOR]

One of the fastest-expanding study areas in optics over the past decade has been metasurfaces (MSs). These subwavelength meta-atom-based ultrathin arrays have been developed for a broad range of functions, including lenses, polarization control, holography, coloring, spectroscopy, sensors, and many more. They allow exact control of the many properties of electromagnetic waves. The performance of MSs has dramatically improved because of recent developments in nanofabrication methods, and this concept has developed to the point that it may be used in commercial applications. In this review, a vital topic of sensing has been considered and an up-to-date study has been carried out. Three different kinds of MS absorber sensor formations, all-dielectric, all-metallic, and hybrid configurations, are presented for biochemical sensing applications. We believe that this review paper will provide current knowledge on state-of-the-art sensing devices based on MSs. [ABSTRACT FROM AUTHOR]

Chitosan (CTS) has been used as a nerve guidance conduit (NGC) material for bridging peripheral nerve defects due to its biocompatible, biodegradable, and non-toxic properties. However, the nerve regeneration effect of chitosan alone is restricted due to its inadequate biological activity. Herein, a composite, bioactive chitosan based nerve conduit, consisting of outer warp-knitted tube scaffold made from medical-grade chitosan fiber, and inner porous cross linked carboxymethyl chitosan (C-CM-CTS) sponge with radial texture was developed. The inner wall of the scaffold was coated with C-CM-CTS solution. CM-CTS provided favorable bioactivities in the composite chitosan-based nerve conduit. An in vitro study of CM-CTS revealed its satisfying biocompatibility with fibroblast and its inhibition of oxidative damage to Schwann cells. As the internal filler of the NGC, the lyophilized sponge of C-CM-CTS showed a longitudinal guidance effect for nerve reconstruction. After 10 mm defect in rat sciatic nerve was bridged with the composite bioactive chitosan-based nerve conduit, the nerve conduit was able to effectively promote axonal regeneration and played a positive role in inducing nerve regeneration and functional recovery. In addition to the functional advantages, which are equal to those of an autograft; the technology for the preparation of this conduit can be put into mass production. [ABSTRACT FROM AUTHOR]

Background: Extracellular Vesicles (EVs) are sub-micrometer lipid-bound particles released by most cell types. They are considered a promising source of cancer biomarkers for liquid biopsy and personalized medicine due to their specific molecular cargo, which provides biochemical information on the state of parent cells. Despite this potential, EVs translation process in the diagnostic practice is still at its birth, and the development of novel medical devices for their detection and characterization is highly required. Results: In this study, we demonstrate mid-infrared plasmonic nanoantenna arrays designed to detect, in the liquid and dry phase, the specific vibrational absorption signal of EVs simultaneously with the unspecific refractive index sensing signal. For this purpose, EVs are immobilized on the gold nanoantenna surface by immunocapture, allowing us to select specific EV sub-populations and get rid of contaminants. A wet sample-handling technique relying on hydrophobicity contrast enables effortless reflectance measurements with a Fourier-transform infrared (FTIR) spectro-microscope in the wavelength range between 10 and 3 µm. In a proof-of-principle experiment carried out on EVs released from human colorectal adenocarcinoma (CRC) cells, the protein absorption bands (amide-I and amide-II between 5.9 and 6.4 µm) increase sharply within minutes when the EV solution is introduced in the fluidic chamber, indicating sensitivity to the EV proteins. A refractive index sensing curve is simultaneously provided by our sensor in the form of the redshift of a sharp spectral edge at wavelengths around 5 µm, where no vibrational absorption of organic molecules takes place: this permits to extract of the dynamics of EV capture by antibodies from the overall molecular layer deposition dynamics, which is typically measured by commercial surface plasmon resonance sensors. Additionally, the described metasurface is exploited to compare the spectral response of EVs derived from cancer cells with increasing invasiveness and metastatic potential, suggesting that the average secondary structure content in EVs can be correlated with cell malignancy. Conclusions: Thanks to the high protein sensitivity and the possibility to work with small sample volumes—two key features for ultrasensitive detection of extracellular vesicles- our lab-on-chip can positively impact the development of novel laboratory medicine methods for the molecular characterization of EVs. [ABSTRACT FROM AUTHOR]

We design, fabricate, optically and mechanically characterize wearable ultrathin coatings on various substrates, including sapphire, glass and silicon wafer. Extremely hard ceramic materials titanium nitride (TiN), aluminium nitride (AlN), and titanium aluminium nitride (TiAlN) are employed as reflective, isolated and absorptive coating layer, respectively. Two types of coatings have been demonstrated. First, we deposit TiAlN after TiN on various substrates (TiAlN-TiN, total thicknesses <100 nm), achieving vivid and viewing-angle independent surface colors. The colors can be tuned by varying the thickness of TiAlN layer. The wear resistance of the colorful ultrathin optical coatings is verified by scratch tests. The Mohs hardness of commonly used surface coloring made of Si-/Ge-metals on substrates is <2.5, as soft as fingernail. However, the Mohs hardness of our TiAlN-TiN on substrates is evaulated to be 7-9, harder than quartz. Second, Fano-resonant optical coating (FROC), which can transmit and reflect the same color as a beam split filter is also obtained by successively coating TiAlN-TiN-AlN-TiN (four-layer film with a total thickness of 130 nm) on transparent substrates. The FROC coating is as hard as glass. Such wearable and color-tunable thin-film structural colors and filters may be attractive for many practical applications such as sunglasses. [ABSTRACT FROM AUTHOR]

Although metasurfaces have received enormous attention and are widely applied in various fields, the realization of multiple functions using a single metasurface is still rarely reported to date. In this work, we propose a novel dual-functional metasurface that can be applied as a mid-infrared narrowband thermal light source in optical gas sensing and a long-wave infrared broadband absorber in photodetection. By actively tailoring the structure and constituent materials of the metasurface, the device yields an absorptivity of over 90% from 8 µm to 14 µm, while it exhibits an emissivity of 97.4% at the center wavelength of 3.56 μm with a full width at half-maximum of 0.41 µm. Notably, the metasurface is insensitive to the incident angle under both TM- and TE-polarized light. The proposed dual-functional metasurface possesses many advantages, including a simple structure, thin thickness, angle and polarization insensitivity, and compatibility with optical devices, which are expected to simplify the existing imaging systems and improve the performance of photodetection equipment. [ABSTRACT FROM AUTHOR]

Highlights: A loss-engineered multi-hotspot strategy is proposed by integrating all major optimization methods to improve the sensitivity and signal intensity of plasmonic nanoantennas for mid-infrared (MIR) absorption-based molecule sensing. The physi-chemisorption mechanism of hybrid metal–organic framework (MOF)-polymers is demonstrated to break through the limit of detection for MIR gas sensing. MOFs and nanoantennas are successfully integrated to achieve high-performance gas detection, including low detection limit, high sensitivity (0.18%/ppm), excellent reversibility (variation within 2%), high selectivity, and nm-level optical interaction length.Metal–organic frameworks (MOFs) have been extensively used for gas sorption, storage and separation owing to ultrahigh porosity, exceptional thermal stability, and wide structural diversity. However, when it comes to ultra-low concentration gas detection, technical bottlenecks of MOFs appear due to the poor adsorption capacity at ppm-/ppb-level concentration and the limited sensitivity for signal transduction. Here, we present hybrid MOF-polymer physi-chemisorption mechanisms integrated with infrared (IR) nanoantennas for highly selective and ultrasensitive CO2 detection. To improve the adsorption capacity for trace amounts of gas molecules, MOFs are decorated with amino groups to introduce the chemisorption while maintaining the structural integrity for physisorption. Additionally, leveraging all major optimization methods, a multi-hotspot strategy is proposed to improve the sensitivity of nanoantennas by enhancing the near field and engineering the radiative and absorptive loss. As a benefit, we demonstrate the competitive advantages of our strategy against the state-of-the-art miniaturized IR CO2 sensors, including low detection limit, high sensitivity (0.18%/ppm), excellent reversibility (variation within 2%), and high selectivity (against C2H5OH, CH3OH, N2). This work provides valuable insights into the integration of advanced porous materials and nanophotonic devices, which can be further adopted in ultra-low concentration gas monitoring in industry and environmental applications. [ABSTRACT FROM AUTHOR]

Metamaterials have proven their ability to possess extraordinary physical properties distinct from naturally available materials, leading to exciting sensing functionalities and applications. However, metamaterial‐based sensing applications suffer from severe performance limitations due to noise interference and design constraints. Here, we propose a dual‐phase strategy that leverages loss‐induced different Fano‐resonant phases to access both destructive and constructive signals of molecular vibration. When the two reverse signals are innovatively combined, the noise in the detection system is effectively suppressed, thereby breaking through the noise‐related limitations. Additionally, by utilizing loss optimization of the plasmon‐molecule coupling system, our dual‐phase strategy enhances the efficiency of infrared energy transfer into the molecule without any additional fabrication complex, thereby overcoming the trade‐off dilemma between performance and fabrication cost. Thanks to the pioneering breakthroughs in the limitations, our dual‐phase strategy possesses an overwhelming competitive advantage in ultrasensitive vibrational spectroscopy over traditional metamaterial technology, including strong signal strength (×4), high sensitivity (×4.2), effective noise suppression (30%), low detection limit (13 ppm), and excellent selectivity among CO2, NH3, and CH4 mixtures. This work not only opens the door to various emerging ultrasensitive detection applications, including ultrasensitive in‐breath diagnostics and high‐information analysis of molecular information in dynamic reactions, but also gains new insights into the plasmon‐molecule interactions in advanced metamaterials. [ABSTRACT FROM AUTHOR]

Objectives: This scoping review explores the risk and management of traumatic injuries to the inferior alveolar and lingual nerves during mandibular dental procedures. Emphasizing the significance of diagnostic tools, the review amalgamates existing knowledge to offer a comprehensive overview., Materials and Methods: A literature search across PubMed, Embase, and Cochrane Library informed the analysis., Results: Traumatic injuries often lead to hypo-/anesthesia and neuropathic pain, impacting individuals psychologically and socially. Diagnosis involves thorough anamnesis, clinical-neurological evaluations, and radiographic imaging. Severity varies, allowing for conservative or surgical interventions. Immediate action is recommended for reversible causes, while surgical therapies like decompression, readaptation, or reconstruction yield favorable outcomes. Conservative management, utilizing topical anesthesia, capsaicin, and systemic medications (tricyclic antidepressants, antipsychotics, and serotonin-norepinephrine-reuptake-inhibitors), proves effective for neuropathic pain., Conclusions: Traumatic nerve injuries, though common in dental surgery, often go unrecorded. Despite lacking a definitive diagnostic gold standard, a meticulous examination of the injury and subsequent impairments is crucial., Clinical Relevance: Tailoring treatment to each case's characteristics is essential, recognizing the absence of a universal solution. This approach aims to optimize outcomes, restore functionality, and improve the quality of life for affected individuals., (© 2024. The Author(s).)

Superoxide dismutases (SODs) belong to the group of metalloenzymes that remove superoxide anion radicals and they have been identified in three domains of life: Bacteria, Archaea and Eucarya. SODs in Synechocystis sp. PCC 6803, Gloeobacter violaceus CCALA 979, and Geitlerinema sp. ZHR1A were investigated. We hypothesized that iron (FeSOD) and/or manganese (MnSOD) dominate as active forms in these cyanobacteria. Activity staining and three different spectroscopic methods of SOD activity bands excised from the gels were used to identify a suitable metal in the separated samples. FeSODs or enzymes belonging to the Fe-MnSOD superfamily were detected. The spectroscopic analyses showed that only Fe is present in the SOD activity bands. We found FeSOD in Synechocystis sp. PCC 6803 while two forms in G. violaceus and Geitlerinema sp. ZHR1A: FeSOD1 and FeSOD2 were present. However, no active Cu/ZnSODs were identified in G. violaceus and Geitlerinema sp. ZHR1A. We have shown that selected spectroscopic techniques can be complementary to the commonly used method of staining for SOD activity in a gel. Furthermore, the occurrence of active SODs in the cyanobacteria studied is also discussed in the context of SOD evolution in oxyphotrophs. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Tissue Engineering Research / Zhongguo Zuzhi Gongcheng Yanjiu is the property of Chinese Journal of Tissue Engineering Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The past few decades have seen rapid advances in surface-enhanced Raman scattering (SERS) techniques which have enabled increasingly efficient detection of infinitesimal molecular traces down to the single molecule. This occurrence paved the way for promising applications, among which the use of SERS in highly efficient label-free optical sensors, thus attaining a large interest, especially in the biomedical field. SERS sensors are realized following different strategies, usually involving the control of size and shape of nanoantennas and the design of nanostructures arrays to precisely set the Localized Surface Plasmon resonances (LSP) and the hot spots positions. However, this may entail the use of lithographic techniques with high fabrication costs. Other approaches are based on disordered arrays of plasmonic nanostructures, much cheaper and easier to fabricate, although the control of the hot spots position and performances is lost. Here we review the more recent SERS strategies approached in order to obtain the desired detection of analytes and specific biomolecular species, ranging from the realization of particularly efficient SERS substrates suitable for hydrated molecules to the creation of hot spots in a liquid environment enabling highly sensitive spectroscopic sensors in the natural habitat of the biomolecules. [ABSTRACT FROM AUTHOR]

Objective: To explore the clinical effects of wrist arthroscopy combined with oblique ulnar shortening osteotomy in the treatment of ulnar impaction syndrome. Methods: This was a retrospective study of 60 patients with ulnar impaction syndrome who were admitted to our department from January 2016 to December 2019. According to different surgical methods, they were divided into an observation group and a control group, with 30 cases in each group. The control group was treated with oblique ulnar shortening osteotomy, and the observation group used wrist arthroscopy based on the control group. The two groups of patients were compared in terms of wrist function before and 12 months after surgery. We compared the Disabilities of the Arm, Shoulder, and Hand Score (DASH Score), Patient‐Rated Wrist Evaluation Score (PRWE Score), Visual Analog Score (VAS), and ulnar variation between the two groups at 12 months after surgery. The excellent and good rates by Mayo wrist score were compared between the two groups at the last follow‐up. Results: All patients were followed up for 12–36 months, with an average of 14.5 months. Bone union was achieved at the oblique osteotomy of the ulna, with an average healing time of 13.6 weeks. The observation group was examined by wrist arthroscopy, and the triangular fibrocartilage complex (TFCC) Palmer classification was confirmed in three cases of type IIA, seven cases of type IIB, 14 cases of type IIC, and six cases of type IID. Compared with before surgery, the grip strength, flexion‐extension, ulnar radial deflection, and forearm rotation of the two groups of patients were significantly improved at 12 months after surgery. The DASH score, PRWE score, and VAS score of the observation group were better than those of the control group, and the difference in ulnar shortening length was not statistically significant between the two groups. The excellent and good rates of the observation group (93.3%) were better than those of the control group (87.5%) at the last follow‐up, and the difference was statistically significant. Conclusion: Compared with oblique ulnar shortening osteotomy alone, combined wrist arthroscopy can better reduce the pain of patients with ulnar impaction syndrome, restore wrist function, and improve the excellent and good rates. Therefore, it is clinically worthy of promotion. [ABSTRACT FROM AUTHOR]

The application of hydrogels in nanophotonics has been restricted due to their low fabrication feasibility and refractive index. Nevertheless, their elasticity and strength are attractive properties for use in flexible, wearable-devices, and their swelling characteristics in response to the relative humidity highlight their potential for use in tunable nanophotonics. We investigate the use of nanostructured polyvinyl alcohol (PVA) using a one-step nanoimprinting technique for tunable and erasable optical security metasurfaces with multiplexed structural coloration and metaholography. The resolution of the PVA nanoimprinting reaches sub-100 nm, with aspect ratios approaching 10. In response to changes in the relative humidity, the PVA nanostructures swell by up to ~35.5%, providing precise wavefront manipulation of visible light. Here, we demonstrate various highly-secure multiplexed optical encryption metasurfaces to display, hide, or destroy encrypted information based on the relative humidity both irreversibly and reversibly. PVA is a hydrogel that has attractive swelling properties for use in tunable photonic applications. Here, the authors exploit PVA with nanoimprint lithography to realize multiplexed optical encryption metasurfaces to display, hide, and destroy encrypted information. [ABSTRACT FROM AUTHOR]

The scattering of electromagnetic waves by a resonator is determined by the excitation of the eigenmodes of the system. In the case of open resonators made of absorbing materials, the system is non-Hermitian, and the eigenmodes are quasinormal modes. Among the whole set of quasinormal modes, static modes (modes with a zero eigenfrequency) occupy a specific place. We study the role of static modes in quasinormal modes expansions calculated with a numerical solver implemented with the finite-element method. We show that, in the case of a dielectric permittivity described by a Lorentz model, static modes markedly contribute to the electromagnetic field reconstruction but are incorrectly calculated with a solver designed to compute modes with non-zero eigenfrequencies. We propose to solve this issue by adding to the solver a separate, specific computation of the static modes. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Central South University is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A kind of gold-coated glass nano-cone-tips (GGNCTs) is developed as an arrayed optical antenna for highly receiving and converging incident lightwaves. A local light field enhancement factor (LFEF) of ~ 2 × 104 and maximum light absorption of ~ 98% can be achieved. The near-field lightwave measurements at the wavelength of 633 nm show that the surface net charges over a single GGNCT make a typical dipole oscillation and the energy transmits along the wave vector orientation, thus leading to a strong local light field enhancement. An effective detection method by near-field coupling an arrayed GGNCT and complementary metal–oxide–semiconductor (CMOS) sensor for highly efficient imaging detection is proposed. The lightwave detection at several wavelengths, including typical 473 nm, 532 nm, 671 nm, and 980 nm, shows a notable characteristic that a better capability of the net charge distribution adjusting and localized aggregating can be obtained at the absorption peak of the GGNCT developed and a stronger signal detection achieved. The research lays a foundation for further developing a light detector with an ideal optoelectronic sensitivity and broad spectral suitability, which is based on integrating GGNCTs as an arrayed optical antenna with common sensors. [ABSTRACT FROM AUTHOR]

Metasurfaces can enable the confinement of electromagnetic fields on huge surfaces and zones, and they can thus be applied to biochemical sensing by using surface-enhanced Raman scattering (SERS) and surface-enhanced infrared absorption (SEIRA). Indeed, these metasurfaces have been examined for SERS and SEIRA sensing thanks to the presence of a wide density of hotspots and confined optical modes within their structures. Moreover, some metasurfaces allow an accurate enhancement of the excitation and emission processes for the SERS effect by supporting resonances at frequencies of these processes. Finally, the metasurfaces allow the enhancement of the absorption capacity of the solar light and the generation of a great number of catalytic active sites in order to more quickly produce the surface reactions. Here, we outline the latest advances in metasurfaces for SERS and SEIRA sensors as well as photocatalysis. [ABSTRACT FROM AUTHOR]