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Multi-modal strategies for optical information storage have received a lot of attention to meet the increasing security requirements. In this case, long persistent luminescence (LPL) phosphors with different dopant ions were obtained by introducing Dy3+ and Ho3+ ions into the BaSi 2 O 5 :Eu2+ phosphor to adjust the distribution and depth of the trap centers. The generation of the pure phase BaSi 2 O 5 was confirmed by X-ray diffraction (XRD) and XRD Rietveld refinement. The peak emission of BaSi 2 O 5 : Eu2+ phosphor is about 500 nm with 313 nm excitation. Both BaSi 2 O 5 : Eu2+, Dy3+, and BaSi 2 O 5 : Eu2+, Ho3+ phosphors exhibit emission characteristics of Eu2+ ions. The trap depths of the three phosphors are different by Gaussian fitting of thermoluminescence (TL) curves, and the depth of BaSi 2 O 5 : Eu2+, Dy3+ phosphor can reach 1.070 eV. Typically, the flexible luminescent film based on BaSi 2 O 5 : Eu2+ phosphor can be written optical pattern using 365 nm ultraviolet (UV) light, such as "DL" and "fireworks" patterns, and subsequently read out by thermal or infrared light stimulus. Further, a strategy for encryption and decryption of dynamic optical information in Morse code has been developed using BaSi 2 O 5 : Eu2+, BaSi 2 O 5 : Eu2+, Dy3+, and BaSi 2 O 5 : Eu2+, Ho3+ phosphors, indicating the prospective use in optical information security. [ABSTRACT FROM AUTHOR]

Surface electromyography (sEMG) signal is a kind of physiological signal reflecting muscle activity and muscle force. At present, the existing methods of recognizing human motion intention need more than two sensors to recognize more than two kinds of movements, the sensor pasting positions are special, and the hardware conditions for execution are high. In this work, a real-time motion intention recognition method based on Morse code is proposed and applied to the mechanical hand. The short-time and long-term muscle contraction signals collected by a single sEMG sensor were extracted and encoded with the Morse code method, and then the developed mapping method from Morse code to six hand movements were used to recognize hand movements. The average recognition accuracy of hand movements was 94.8704 ± 2.3556%, the average adjusting time was 34.89 s for all subjects, and the execution time of a single movement was 381 ms. The corresponding experiment video can be found in the attachment to show the experiment. The method proposed in this work is a method with one sensor to recognize six movements, low hardware conditions, high recognition accuracy, and insensitive to the difference of sensor pasting position. The main characteristics of this work are as follows. 1) The sEMG signals of short-time muscle contraction and long-time muscle contraction are encoded as Morse code to realize the recognition of six movements. 2) This work only uses Morse code and multiple judgments combined with marker bits to realize action recognition. It doesn't use the sophisticated machine learning and deep learning methods. Therefore, it is simple to calculate and does not need to collect a large amount of data in advance for training the model. 3) This work does not need to collect a large amount of data from subjects in advance to train the model, so there is no consistency requirement for human individuals and human posture. 4) This method makes equal scaling and threshold determination according to the amplitude of the integrated sEMG (IEMG) signal, so it is not necessary to ensure that the pasting position of the sEMG sensor in each measurement is consistent. [ABSTRACT FROM AUTHOR]

During the late 19th and early 20th centuries, weather observers used a cipher code to transmit weather observations via telegraph. The code, developed by Cleveland Abbe, contained nearly 3,000 words that corresponded to specific weather elements and conditions. The code evolved over time and was used by the national weather service, but its arbitrary selection of code words made it challenging to decipher. In 1887, a new code was introduced to simplify the process and reduce costs, using consonants and vowels to represent measurements. The word-based Weather Code was eventually replaced with a numeric code in 1939, but gained renewed attention when coded messages were discovered in a silk dress from the 1880s. [Extracted from the article]

Integrating tactile feedback through haptic interfaces enhances experiences in virtual and augmented reality. However, electrotactile systems, which stimulate mechanoreceptors directly, often yield inconsistent tactile results due to variations in pressure between the device and the finger. In this study, we present the integration of a transparent electrotactile screen with pressure-sensitive transistors, ensuring highly consistent quantitative haptic sensations. These transistors effectively calibrate tactile variations caused by touch pressure. Additionally, we explore remote-distance tactile stimulations achieved through the interference of electromagnetic waves. We validated tactile perception using somatosensory evoked potentials, monitoring the somatosensory cortex response. Our haptic screen can stimulate diverse electrotactile sensations and demonstrate various tactile patterns, including Morse code and Braille, when integrated with portable smart devices, delivering a more immersive experience. Furthermore, interference of electric fields allows haptic stimulation to facilitate diverse stimulus positioning at lower current densities, extending the reach beyond direct contact with electrodes of our screen. Electrotactile systems can have inconsistent tactile results due to variations in pressure between the device and finger. Here, the authors report a transparent electrotactile device with pressure-sensitive transistors, enabling consistent electrotactility while interference stimulation maximizes the performance. [ABSTRACT FROM AUTHOR]

Conductive hydrogels are gaining significant attention as promising candidates for the fabrication materials for flexible electronics. Nevertheless, improving the tensile properties, hysteresis, durability, adhesion, and electrochemical properties of these hydrogels remains challenging. This work reports the development of a novel semi‐interpenetrating network poly(ionic liquid) hydrogel named PATV, via the in situ polymerization of acrylamide, N‐[Tris(hydroxymethyl)methyl] acrylamide, and 1‐vinyl‐3‐butylimidazolium tetrafluoroborate. The density functional theory calculations reveal that the poly(ionic liquid) in the hydrogel network acts as physical cross–linking points to construct hydrogen‐bond networks. Furthermore, the hydrogen‐bond networks dissipate energy efficiently and quickly, and thus stress concentration and hysteresis are avoided. The prepared hydrogel has a low hysteresis (9%), high tensile properties (900%), fast response (180 ms), high sensitivity (gauge factor = 10.4, pressure sensitivity = 0.14 kPa−1), and wide sensing range (tensile range: 1–600%, compression range: 0.1–20 kPa). A multifunctional sensor designed based on the designed hydrogel enables real‐time, rapid, and stable response‐ability for the detection of human movement, facial expression recognition, pronunciation, pulse, handwriting, and Morse code encryption. Furthermore, the assembled triboelectric nanogenerator displays an excellent energy harvesting capability, thus highlighting its potential application in self‐powered flexible wearable electronic devices. [ABSTRACT FROM AUTHOR]

Transparent photovoltaics (TPVs) are crucial for developing next‐generation see‐through electronics. However, TPV devices (TPVDs) require wide‐bandgap materials that are typically only responsive to short wavelength (ultraviolet, UV) lights rather than visible lights. Is it possible to improve the TPV performance by harvesting the longer wavelength lights without degradation of transparency? It may be satisfied with the function of intermediate energy states, which can utilize the lower photon energy (longer wavelength light) by a two‐step transition. To achieve this, co‐sputtered Ti‐doped ZnO (Ti:ZnO) film‐based high‐performance TPVDs have been developed. Density functional theory analysis revealed the formation of intermediate energy states due to the hybridization of O 2p and Ti 3d orbitals in the Ti:ZnO system. The Ti:ZnO‐based TPVDs show 65% average visible transparency with a power production value of 655 μW cm−2. These devices exhibit good photodetection behavior under UV to visible illuminations with high responsivity and detectivity values of 1.85 A W−1 and 2.5 × 1013 Jones, respectively. Finally, a high‐performance UV to visible broadband and wide‐field‐of‐view photocommunication system is designed based on the TPVDs to generate the fast Morse code signal. Therefore, Ti doping in ZnO provides a good way to improve the device's functionality for futuristic applications. [ABSTRACT FROM AUTHOR]

Triboelectric nanogenerators (TENGs) are promising candidates replacing conventional batteries in wearable devices, owing to their self‐powering properties. Although TENGs can convert mechanical energy into electrical energy, excessive mechanical stresses can degrade their performance. Moreover, conformal adhesion to skin is required to improve its performance in wearable devices. Here, a stretchable, adhesive, and self‐healing single‐electrode TENG with a multifunctional hydrogel‐elastomer double layer is developed. Carbon nanotubes (CNTs)‐doped hydrogel is used as the electrode. Subsequently, the electrode is covered with an Ecoflex elastomer that acted as a triboelectrification layer. The soft tissue‐like properties of the hydrogel allow conformal adhesion to nonplanar skin, whereas the dynamic polymer network of the hydrogel endows toughness and ability to self‐heal (within 5 min) against external damage. The TENG demonstrates an output voltage and current peak at 180 V and 0.8 µA. Moreover, it can generate a maximum power peak at 37.8 mW m−2, which is sufficient to power small electronics like stopwatches and light‐emitting diodes, with a power management circuit. The proposed TENG devices can function as telecommunication touch panels via Morse code. Thus, this study presents a promising approach for advancing the flexible power supplies and self‐powered sensors that can be applied to wearable devices. [ABSTRACT FROM AUTHOR]

Microstructures have been proved as crucial factors for the sensing performance of flexible pressure sensors. In this study, polypyrrole (PPy)/sunflower pollen (SFP) (P/SFP) was prepared via the in situ growth of PPy on the surface of degreased SFP with a sea urchin-like microstructure; then, these P/SFP microspheres were sprayed onto a flat silk cocoon (FSC) to prepare a sensing layer P/SFP-FSC. PPy-FSC (P-FSC) was prepared as an electrode layer through the in situ polymerization of PPy on the FSC surface. The sensing layer P/SFP-FSC was placed between two P-FSC electrode layers to assemble a P/SFP-FSC pressure sensor together with a fork finger electrode. With 6 mg/cm2 of optimized sprayed P/SFP microspheres, the prepared flexible pressure sensor has a sensitivity of up to 0.128 KPa−1 in the range of 0–13.18 KPa and up to 0.13 KPa−1 in the range of 13.18–30.65 KPa, a fast response/recovery time (90 ms/80 ms), and a minimum detection limit as low as 40 Pa. This fabricated flexible P/SFP-FSC sensor can monitor human motion and can also be used for the encrypted transmission of important information via Morse code. In conclusion, the developed flexible P/SFP-FSC pressure sensor based on microstructure modification in this study shows good application prospects in the field of human–computer interaction and wearable electronic devices. [ABSTRACT FROM AUTHOR]

Flexible strain sensors are essential components for wearable devices, human‐machine interaction systems, and intelligent soft robots. Current active strain sensors have high power consumption, while passive strain sensors exhibit limitations in detecting static or slowly‐varying stimulations. Here, inspired by the strain sensing behavior of Ruffini endings in natural skin, a new type of potentiometric, fully passive, and highly stretchable strain sensors are presented based on the mechanical regulation of ionically conductive percolating networks. Specifically, an artificial potential difference is first created with two electrochemical active electrodes, followed by encoding external strain stimulations into the potential difference variations using a new class of highly elastic and ionically conductive composites with configurable ionic percolating networks. Based on the proposed passive strain sensing mechanism, both static and slowly‐varying strain stimulations (up to 100%) can be monitored with ultralow power consumption (at nW level). Promising applications of the passive strain sensors in human motion monitoring, Morse code communication, and hand gesture recognition are demonstrated. This work opens up a new avenue to constructing novel strain sensing devices with high stretchability, ultralow power consumption, and desirable sensing performance. [ABSTRACT FROM AUTHOR]

With the rapid development of wearable devices, tactile sensors have received extensive attention as supplements to vision and hearing. However, it remains challenging for a single tactile sensor to generate distinguishable electrical signals when receiving mechanical stimuli in different directions. Herein, a novel flexible electromagnetic tactile sensor (FETS) prepared by combining flexible double‐layer coils and a flexible tilted magnetic column array (TMCA) is presented. Flexible double‐layer high‐density coils are fabricated using the micro‐electromechanical system (MEMS) technology. The turns of the coil (1 × 1 cm) are 100, while both the line width and spacing of turns are 40 µm. TMCA is prepared using a template and magnetized along the axis direction. When a pulling force or pressure is applied to the TMCA, the magnetic flux decreases or increases correspondingly, allowing the FETS to accurately distinguish stimuli and produce different signals (−/+ or +/−). The FETS presents a sensitivity of up to 21.7 µV kPa−1 (0.05–10 kPa), a minimal magnetic field detection limit of 10 mT, a low‐pressure detection limit of 5 g, and good repeatability (5000 cycles). Additionally, the FETS is applied in robotic tactile testing, Morse code, and noncontact magnetic field recognition. It has potential applications in the Internet of Things (IoT) and information communication. [ABSTRACT FROM AUTHOR]

Morse code recognition plays a very important role in the application of human–machine interaction. In this paper, based on the carbon nanotube (CNT) and polyurethane sponge (PUS) composite material, a flexible tactile CNT/PUS sensor with great piezoresistive characteristic is developed for detecting Morse code precisely. Thirty-six types of Morse code, including 26 letters (A–Z) and 10 numbers (0–9), are applied to the sensor. Each Morse code was repeated 60 times, and 2160 (36 × 60) groups of voltage time-sequential signals were collected to construct the dataset. Then, smoothing and normalization methods are used to preprocess and optimize the raw data. Based on that, the long short-term memory (LSTM) model with excellent feature extraction and self-adaptive ability is constructed to precisely recognize different types of Morse code detected by the sensor. The recognition accuracies of the 10-number Morse code, the 26-letter Morse code, and the whole 36-type Morse code are 99.17%, 95.37%, and 93.98%, respectively. Meanwhile, the Gated Recurrent Unit (GRU), Support Vector Machine (SVM), Multi-Layer Perceptron (MLP), and Random Forest (RF) models are built to distinguish the 36-type Morse code (letters of A–Z and numbers of 0–9) based on the same dataset and achieve the accuracies of 91.37%, 88.88%, 87.04%, and 90.97%, respectively, which are all lower than the accuracy of 93.98% based on the LSTM model. All the experimental results show that the CNT/PUS sensor can detect the Morse code's tactile feature precisely, and the LSTM model has a very efficient property in recognizing Morse code detected by the CNT/PUS sensor. [ABSTRACT FROM AUTHOR]

The von Neumann bottleneck is a critical limitation in synaptic devices. Therefore, artificial synaptic devices resembling biological neuromorphic synapses have been developed to overcome the von Neumann bottleneck. However, synaptic devices require voltages, which results in considerable energy consumption. Here, photonic synaptic devices with the vertical structure of indium tin oxide (ITO)/SnO2/Al2O3/CsBi3I10/Au are fabricated, which can work in the self-powered mode owing to the photovoltaic effect endowed by a vertical multilayer structure. Several fundamental synaptic functions, such as excitatory postsynaptic current, paired-pulse facilitation, short-term plasticity (STP), long-term plasticity (LTP), pulse-frequency-dependent plasticity, transition of STP to LTP, and the learning experience are emulated. Moreover, Morse-coded external light information is decoded by self-powered photonic synaptic devices. The results indicate that self-powered photonic synaptic devices based on lead-free perovskites exhibit great potential for efficient neuromorphic computing and optical wireless communication. [ABSTRACT FROM AUTHOR]

Flexible sensors have been widely studied for use in motion monitoring, human‒machine interactions (HMIs), personalized medicine, and soft intelligent robots. However, their practical application is limited by their low output performance, narrow measuring range, and unidirectional force detection. Here, to achieve flexibility and high performance simultaneously, we developed a flexible wide-range multidimensional force sensor (FWMFS) similar to bones embedded in muscle structures. The adjustable magnetic field endows the FWMFS with multidimensional perception for detecting forces in different directions. The multilayer stacked coils significantly improved the output from the μV to the mV level while ensuring FWMFS miniaturization. The optimized FWMFS exhibited a high voltage sensitivity of 0.227 mV/N (0.5–8.4 N) and 0.047 mV/N (8.4–60 N) in response to normal forces ranging from 0.5 N to 60 N and could detect lateral forces ranging from 0.2–1.1 N and voltage sensitivities of 1.039 mV/N (0.2–0.5 N) and 0.194 mV/N (0.5–1.1 N). In terms of normal force measurements, the FWMFS can monitor finger pressure and sliding trajectories in response to finger taps, as well as measure plantar pressure for assessing human movement. The plantar pressure signals of five human movements collected by the FWMFS were analyzed using the k-nearest neighbors classification algorithm, which achieved a recognition accuracy of 92%. Additionally, an artificial intelligence biometric authentication system is being developed that classifies and recognizes user passwords. Based on the lateral force measurement ability of the FWMFS, the direction of ball movement can be distinguished, and communication systems such as Morse Code can be expanded. This research has significant potential in intelligent sensing and personalized spatial recognition. [ABSTRACT FROM AUTHOR]

In recent years, hydrogel-based wearable flexible electronic devices have attracted much attention. However, hydrogel-based sensors are affected by structural fatigue, material aging, and water absorption and swelling, making stability and accuracy a major challenge. In this study, we present a DN-SPEZ dual-network hydrogel prepared using polyvinyl alcohol (PVA), sodium alginate (SA), ethylene glycol (EG), and ZnSO4 and propose a self-calibration compensation strategy. The strategy utilizes a metal salt solution to adjust the carrier concentration of the hydrogel to mitigate the resistance drift phenomenon to improve the stability and accuracy of hydrogel sensors in amphibious scenarios, such as land and water. The ExpGrow model was used to characterize the trend of the ∆R/R0 dynamic response curves of the hydrogels in the stress tests, and the average deviation of the fitted curves ϵ ¯ was calculated to quantify the stability differences of different groups. The results showed that the stability of the uncompensated group was much lower than that of the compensated group utilizing LiCl, NaCl, KCl, MgCl2, and AlCl3 solutions ( ϵ ¯ in the uncompensated group in air was 276.158, 1.888, 2.971, 30.586, and 13.561 times higher than that of the compensated group in LiCl, NaCl, KCl, MgCl2, and AlCl3, respectively; ϵ ¯ in the uncompensated group in seawater was 10.287 times, 1.008 times, 1.161 times, 4.986 times, 1.281 times, respectively, higher than that of the compensated group in LiCl, NaCl, KCl, MgCl2 and AlCl3). In addition, for the ranking of the compensation effect of different compensation solutions, the concentration of the compensation solution and the ionic radius and charge of the cation were found to be important factors in determining the compensation effect. Detection of events in amphibious environments such as swallowing, robotic arm grasping, Morse code, and finger–wrist bending was also performed in this study. This work provides a viable method for stability and accuracy enhancement of dual-network hydrogel sensors with strain and pressure sensing capabilities and offers solutions for sensor applications in both airborne and underwater amphibious environments. [ABSTRACT FROM AUTHOR]

Introduction: Tinea capitis (TC) is a common fungal infection of the scalp, especially in children. Trichoscopy is a noninvasive technique that allows rapid and magnified in vivo observation of the hair with the visualization of morphologic features that are often imperceptible to the naked eye. Aim: This study aimed to evaluate the usefulness of trichoscopy in clinical diagnosis and to study various clinico‑morphological patterns of TC. Materials and Methods: This cross-sectional, observational study included 140 clinically diagnosed cases of TC seen during a period of 1 year (April 2021 to March 2022). All patients were evaluated using a dermoscope (DermLite DL4 Multispectral 3 Gen, San Juan Capistrano, CA, USA,10×). Results: The prevalence rate of TC in this study was 2.69 per thousand population. The most common clinical variant was gray patch followed by kerion and black dot, and the most common etiological agent was Trichophyton tonsurans. The characteristic trichoscopic features were as follows: comma hairs (80%), followed by corkscrew hairs (68.6%), bent hairs (54.2%), zigzag hairs (35.7%), and morse code‑like hairs (15%). Other findings included scaling (89.2%), followed by black dot (67.1%), broken hairs (42.8%), and crusting and pustules (32.1% each). Comma and corkscrew‑shaped hairs were most common in the black dot type, whereas zigzag, bent hairs, and morse code hairs were common in the gray patch type of TC. There was a significant association between trichoscopic findings and type of TC. Conclusion: Trichoscopy can be considered a novel tool for rapid diagnosis and selection of the appropriate therapy and in the monitoring of treatment efficacy in TC. [ABSTRACT FROM AUTHOR]

The practical application of flexible pressure sensors, including electronic skins, wearable devices, human–machine interaction, etc., has attracted widespread attention. However, the linear response range of pressure sensors remains an issue. Ecoflex, as a silicone rubber, is a common material for flexible pressure sensors. Herein, we have innovatively designed and fabricated a pressure sensor with a gradient micro-cone architecture generated by CO2 laser ablation of MWCNT/Ecoflex dielectric layer film. In cooperation with the gradient micro-cone architecture and a dielectric layer of MWCNT/Ecoflex with a variable high dielectric constant under pressure, the pressure sensor exhibits linearity (R2 = 0.990) within the pressure range of 0–60 kPa, boasting a sensitivity of 0.75 kPa−1. Secondly, the sensor exhibits a rapid response time of 95 ms, a recovery time of 129 ms, hysteresis of 6.6%, and stability over 500 cycles. Moreover, the sensor effectively exhibited comprehensive detection of physiological signals, airflow detection, and Morse code communication, thereby demonstrating the potential for various applications. [ABSTRACT FROM AUTHOR]

Understanding encoded language, such as written words, requires multiple cognitive processes that act in a parallel and interactive fashion. These processes and their interactions, however, are not fully understood. Various conceptual and methodical approaches including computational modeling and neuroimaging have been applied to better understand the neural underpinnings of these complex processes in the human brain. In this study, we tested different predictions of cortical interactions that derived from computational models for reading using dynamic causal modeling. Morse code was used as a model for non-lexical decoding followed by a lexical-decision during a functional magnetic resonance examination. Our results suggest that individual letters are first converted into phonemes within the left supramarginal gyrus, followed by a phoneme assembly to reconstruct word phonology, involving the left inferior frontal cortex. To allow the identification and comprehension of known words, the inferior frontal cortex then interacts with the semantic system via the left angular gyrus. As such, the left angular gyrus is likely to host phonological and semantic representations and serves as a bidirectional interface between the networks involved in language perception and word comprehension. [ABSTRACT FROM AUTHOR]

This document is a correction notice for an article titled "Carbon nanotube modified cellulose nonwovens: superhydrophobic, breathable, and sensitive for drowning alarm and motion monitoring." The authors of the original article discovered an error in their data processing, which resulted in a deviation in the results. They have updated the sensitivity section in Figures 4 and 6, as well as the relative resistance values in Figures 5, 8, and 9. The authors apologize for any inconvenience or confusion caused by this error. The corrected version of the figures is provided in this correction. [Extracted from the article]

Background: Tinea incognito presents with atypical, widespread, and recurrent lesions. Dermoscopy can aid its rapid diagnosis. Aim and Objectives: This study aimed at assessing dermoscopic features and response to treatment in patients with tinea incognito. Materials and Methods: An evaluation of 62 patients with tinea of glabrous skin (Group A (cases)—31 steroid modified and Group B (controls)—31 treatment naïve) was done. Clinical, dermoscopic, and mycological evaluations were done for both groups at baseline, 2, and 4 weeks of terbinafine therapy. Clinical severity (Clinical Assessment Severity Score (CASS) and Visual Analogue Scale (VAS)) and frequency of various dermoscopic changes were compared at 0 and 4 weeks between cases and controls, using unpaired Student's t-test, Mann–Whitney U-test, and Wilcoxon signed-rank test. Results: Baseline dermoscopic features for both groups were significantly different with respect to frequency of broken hair, bent hair, micropustules and Morse code hair. Earliest feature to resolve with treatment was micropustules at 2 weeks. Significant reduction in frequency of morphologically altered hair was evident at 4 weeks. Telangiectasia, dotted vessels, I-hair, and broken hair persisted for a longer period of time. Terbinafine for 4 weeks was an effective treatment, producing complete cure in 73% of cases and 93% of controls. Persistent dermoscopic changes at 2 weeks were found to be associated with treatment failure at 4 weeks, highlighting the role of dermoscopy in identifying patients requiring prolonged treatment. Conclusions: Dermoscopy can be used as a diagnostic and monitoring tool for tinea of glabrous skin. [ABSTRACT FROM AUTHOR]

The flexoelectric phenomenon, which occurs when materials undergo mechanical deformation and cause strain gradients and a related spontaneous electric polarization field, can result in wide variety of energy‐ and cost‐saving mechano‐opto‐electronics, such as night vision, communication, and security. However, accurate sensing of weak intensities under self‐powered conditions with stable photocurrent and rapid temporal response remains essential despite the challenges related to having suitable band alignment and high junction quality. Taking use of the flexoelectric phenomena, it is shown that a centrosymmetric VO2‐based heterojunction exhibits a self‐powered (i.e., 0 V), infrared (λ = 940 nm) photoresponse. Specifically, the device shows giant current modulation (103%), good responsivity of >2.4 mA W−1, reasonable specific detectivity of ≈1010 Jones, and a fast response speed of 0.5 ms, even at the nanoscale modulation. Through manipulation of the applied inhomogeneous force, the sensitivity of the infrared response is enhanced (> 640%). Ultrafast night optical communication like Morse code distress (SOS) signal sensing and high‐performing obstacle sensors with potential impact alarms are created as proof‐of‐concept applications. These findings validate the potential of emerging mechanoelectrical coupling for a wide variety of novel applications, including mechanoptical switches, photovoltaics, sensors, and autonomous vehicles, which require tunable optoelectronic performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hydrophobic eutectogel is facilely produced through the polymerization of hydrophobic monomers in a hydrophobic DES. • The hydrophobic eutectogel shows outstanding water resistance (water contact angle over 110°) and extraordinary durability (over 1000 testing cycles) underwater. • Hydrophobic eutectogel can be utilized as strain and pressure sensors underwater. • Hydrophobic eutectogel sensors can transmit information through Morse code, performing as a underwater communicator. Eutectogels derived from deep eutectic solvents (DESs) exhibit great potential for the fabrication of flexible sensors. However, the hygroscopicity of eutectogels hinders their applications in underwater sensing. In this work, a hydrophobic eutectogel with exceptional long-term underwater stability is produced through one-step polymerization of lauryl methacrylate and glycidyl methacrylate in a hydrophobic DES. The hydrophobic gel network and hydrophobic DES fulfill the eutectogel with outstanding water resistance (water contact angle > 110°) and excellent mechanical properties in an aqueous environment, thus leading to extraordinary durability (over 1000 testing cycles). Additionally, based on this eutectogel, underwater strain and pressure sensors with high sensitivity, rapid responsiveness, and superior durability were fabricated for accurate real-time monitoring of human activity. Furthermore, it has been demonstrated that the eutectogel sensor can transmit information through Morse code, performing as a wearable underwater communicator. This research provides an exemplary way for a demonstration method of hydrophobic eutectogel for durable underwater applications. [ABSTRACT FROM AUTHOR]

The escalating need for enhanced cryptographic security necessitates the development of advanced materials designed for the secure storage and transmission of information. Drawing inspiration from the unique color‐altering and polarizing capabilities of beetles, this work develops a transparent, thermochromic, and circularly polarized cholesteric phase cellulose composite (CPCC). This is achieved by integrating self‐assembled hydroxypropyl cellulose with cholesteric liquid crystal (CLC) structure in tandem with a crosslinked poly(N‐isopropyl acrylamide) (PNIPAM) network. The crosslinking density impacts the response degree of thermochromism, which can be regulated by modifying the UV exposure time during PNIPAM production. The CLC structure in CPCC uniquely results in reflected right circularly polarized light. When coupled with waveplates, this mechanism inverts the rotation direction of the reflected light, creating orthogonal structural colors of different brightness levels under left and right circularly polarized light. The excellent transparency of CPCC facilitates seamless integration with the environment, offering optimal camouflage. Sophisticated techniques, such as color coding and Morse coding, can further be incorporated within the CPCC to increase encryption security and the complexity of decryption. Collectively, the CPCC's transparency, thermochromism, and chirality present significant potential in the design and development of materials for high‐security information encryption, contributing valuable insights to the field. [ABSTRACT FROM AUTHOR]

Amyotrophic lateral sclerosis is a disease that affects nerve cells in the brain. It is indicated by the loss of muscle control which leads to difficulty speaking. Morse code is a communication tool that uses dots and dashes to represent letters. Morse code is an effective communication method for people diagnosed with ALS Since they lose the ability to speak or type with their fingers as the disease progresses. This paper proposes a system for converting Morse Code to text using Arduino Nano and an eye-blink sensor. The proposed system will monitor the eye and the duration of a closed eye ( blink) determines the DOT and DASH. Eventually, the dots and dashes are translated into text and displayed on a 16X2 LCD. [ABSTRACT FROM AUTHOR]

Conductive hydrogels are compelling materials for the development of soft electronics; however, their essential attributes such as high sensitivity, excellent stretchability, and environmental stability have rarely been achieved simultaneously in one hydrogel. Herein, a Kirigami‐inspired strategy is proposed to improve organohydrogel sensitivity without sacrificing their mechanical stretchability and environmental stability. The organohydrogels with multiple interpenetrating networks are synthesized by introducing sodium alginate nanofibrils and conductive MXene nanoflakes into polymer double networks infiltrated with glycerol–water mixtures, featuring remarkable stretchability (>5000%), good sensitivity, and water retention (>30 days). The Kirigami structures are further applied to enhance strain sensitivity, achieving a gauge factor of 29.1, which is ≈5.5 times that of an unstructured organohydrogel. Using the Kirigami‐inspired sensors, a durable glove is developed for grabbing underwater objects through operating a robotic arm, demonstrating a subaqueous interactive human–machine interfacing.Meanwhile, by integrating the wearable sensor with a machine learning algorithm, a wearable Morse code intelligent recognition system is demonstrated, enabling real‐time conversion of Morse code signs into speech with superior recognition accuracy (>99%) and fast response time (≈17 ms). This work offers a new route to synthesize highly sensitive, stretchable, and extremely tolerant organohydrogels, providing a promising platform for next‐generation soft electronics. [ABSTRACT FROM AUTHOR]

In the rapidly evolving digital landscape, secure communication is crucial, and polarization‐sensitive photodetectors offer a promising approach to enhance security and efficiency. However, conventional devices face limitations in encoding capacity due to material‐specific anisotropic properties and geometric factors. In this study, the critical role of the flexoelectric effect in detecting polarized light in silicon and its effective utilization in secure communication systems are demonstrated. The device shows self‐biased photoresponse, which is modulated by up to 320% with the application of force by a sharp probe, a phenomenon attributed to the flexoelectric effect. The polarization sensing behavior is confirmed through comprehensive scanning photocurrent mapping, which is further supported by rigorous finite element simulations. As a potential application, the device is implemented to sense Morse code and effectively modulate it using the flexoelectric effect and light polarization angle, offering more sophisticated encryption methods for secure communication. This research provides valuable insights for advancing secure communication technologies and overcoming the inherent challenges associated with silicon‐based photodetectors. [ABSTRACT FROM AUTHOR]

Wearable and flexible capacitive pressure sensors have recently attracted significant attention in the fields of healthcare monitoring and intelligent human‐machine interaction. While considerable progress is made in achieving high‐pressure resolution over a wide linearity range, practical implementation still faces significant challenges due to complex manufacturing processes, as well as limited accuracy and stability for information transmission. To address these issues, inspiration is drawn from human skin and develop a new hybrid dielectric comprising a low‐permittivity (low‐k) micro‐cilia array and a high‐permittivity (high‐k) foam. Without assistance from an elaborate fabrication methodology, the template‐free method provides a cost‐effective and convenient way to realize the functional dielectric for flexible capacitive sensors. The hybrid dielectric exhibits a pressure‐induced series‐parallel conversion mechanism, enabling effective manipulation of the linear effective dielectric constant and controlled initial/resultant capacitance. Through systematic optimization, the sensor demonstrates a high sensitivity of 0.236 kPa−1 within an ultrabroad linearity range of up to 1100 kPa. Thanks to the unique characteristics of the hybrid dielectric, this device showcases potential applications in various domains including human joint motion analysis, healthcare monitoring, accurate message transmission, and convenient Morse code communication utilizing non‐overlapping capacitance signals. [ABSTRACT FROM AUTHOR]

Information Technology Management is combination of Data Exchange, Algorithm Development, and implementation of various technologies in order to solve the problems related to Information System security. The applications of data science are used by almost all Information Systems in various domains like educational institutions, finance, healthcare, business to handle large volumes of data. The practical applications range from predicting stock movement to predicting cancer. It is used in image processing to identity recognition, audio processing for speech to text prediction. Since authentication and security of the Information System are still not completely secure and is a matter of concern, we are able to implement a real time eyetracing along with the facial feature recognition using Morse Code based secured authentication system to enhance the Security aspects of the Information Systems. Most of the traditional Information Systems have a single layer of security authentication and cannot be relied upon. In our findings, we do not find the existing systems to be completely secure and hence we focus on implementing multiple layers of unique security authentications using eyeball movements to form a distinct Morse Code and the facial feature recognition. [ABSTRACT FROM AUTHOR]

Understanding encoded languages, such as written script or Morse code, requires nonlexical and lexical processing components that act in a parallel and interactive fashion. Decoding written script—as for example in reading—is typically very fast, making the investigation of the lexical and nonlexical components and their underlying neural mechanisms challenging. In the current study, we aimed to accomplish this problem by using Morse code as a model for language decoding. The decoding of Morse code is slower and thus allows a better and more fine‐grained investigation of the lexical and nonlexical components of language decoding. In the current study, we investigated the impact of various components of nonlexical decoding of Morse code using magnetoencephalography. For this purpose, we reconstructed the time–frequency responses below 40 Hz in brain regions significantly involved in Morse code decoding and word comprehension that were identified in a previous study. Event‐related reduction in beta‐ and alpha‐band power were found in left inferior frontal cortex and angular gyrus, respectively, while event‐related theta‐band power increase was found at frontal midline. These induced oscillations reflect working‐memory encoding, long‐term memory retrieval as well as demanding cognitive control, respectively. In sum, by using Morse code and MEG, we were able to identify a cortical network underlying language decoding in a time‐ and frequency‐resolved manner. [ABSTRACT FROM AUTHOR]

With the increasing complexity of the shortwave communication environment, the efficiency and accuracy of the manual detection of Morse code no longer meet actual needs. Therefore, this paper proposes a Morse code detection algorithm called YFDM. For the time–frequency image of the received signal, a combination module of deformable convolution and C3 is used to enhance the backbone network's attention to the abstract semantics and location information of Morse code. GSConv and VOV-GSCSP modules are used to build a lightweight neck network. Finally, the confidence propagation cluster (CP-Cluster) algorithm is used to filter the detection frame. In an ablation experiment, the parameters and giga floating-point operations per second (GFLOPs) of YFDM were 5.961 M and 9.74 G, respectively, 15.11% and 38.9% less than those of YOLOv5. Moreover, when WIoUv1 was used as the loss function of the bounding box, the AP0.5:0.95 and frames per second (FPS) values of the algorithm reached the highest values, 0.68 and 72.4. The experimental results indicate that the algorithm can effectively reduce the weight of the model while ensuring the detection accuracy and inference speed. [ABSTRACT FROM AUTHOR]

Tactile sensing is required for electronic skin and intelligent robots to function properly. However, the dielectric layer's poor structural compressibility in conventional pressure sensors results in a limited pressure sensing range and low sensitivity. To solve this issue, a flexible pressure sensor with a crocodile‐inspired fillable gradient structure is provided. The fillable gradient structure and grooves in the pressure sensor accommodate the deformed microstructure that permits the enhancement of the media layer compressibility via COMSOL finite element simulation and optimization. The pressure sensor exhibits a high sensitivity of up to 0.97 k Pa−1 (0–4 kPa), a wide pressure detection range (7 Pa–380 kPa), and outstanding repeatability. The sensor can detect Morse code, robotic grabbing, and human motion monitoring. As a result, flexible sensors with a bionic fillable gradient structure pave the way for wearable devices and offer a novel method for achieving highly precise tactile perception. [ABSTRACT FROM AUTHOR]

Structurally tunable electronic skin (e‐skin) is beneficial for advancing wearable electronics, prosthetics, and human‐machine interaction (HMI). However, the regulation of e‐skin by traditional nanostructure technology is complex and expensive, moreover, the nanostructure's poor deformability leads to small detection range and low sensitivity. Herein, inspired by the structure of skin‐hair and insect burr, a polypyrrole‐silk/glycerol plasticized silk fibroin (P‐silk/RG) e‐skin fabricated by a simple 3D biomimetic structural strategy is reported. Benefitting from the editability (length, position) of this structure, P‐silk/RG has a signal selectivity, long‐cilia P‐silk/RG demonstrates high sensitivity (respond to weak signal‐airflow), while the short‐cilia P‐silk/RG exhibits wide pressure detection range (0.5–200 g) and high cycle stability (8000 compressions). Therefore, different forms of P‐silk/RG are used in different scenarios (long‐cilia for monitoring breathing and coughing for motion detection and disease diagnosis, short‐cilia for pressure‐sensitive Morse code). Besides, P‐silk/RG exhibits good waterproof, editable conductive points and easy device integration, providing the basis for underwater information transmission, multibit coded command output, and early warning for emergency sports accidents and sedentary. Surprisingly, combining this structure with textile weaving can be mass‐produced. Obviously, this 3D biomimetic structure strategy endows e‐skin with editability and improved scene adaptability to provide a favorable way for mass production. [ABSTRACT FROM AUTHOR]

Polymeric materials exhibiting room temperature phosphorescence (RTP) show a promising application potential. However, the conventional ways of preparing such materials are mainly focused on doping, which may suffer from phase separation, poor compatibility, and lack of effective methods to promote intersystem crossing and suppress the nonradiative deactivation rates. Herein, we present an intrinsically polymeric RTP system producing long-lived phosphorescence, high quantum yields and multiple colors by stepwise structural confinement to tame triplet excitons. In this strategy, the performance of the materials is improved in two aspects simultaneously: the phosphorescence lifetime of one polymer (9VA-B) increased more than 4 orders of magnitude, and the maximum phosphorescence quantum yield reached 16.04% in halogen-free polymers. Moreover, crack detection is realized by penetrating steam through the materials exposed to humid surroundings as a special quenching effect, and the information storage is carried out by employing the Morse code and the variations in lifetimes. This study provides a different strategy for constructing intrinsically polymeric RTP materials toward targeted applications. Materials with room temperature phosphorescence have potential in a range of applications, but preparing the systems can still be challenging. Here, the authors report an intrinsically polymeric room temperature phosphorescent material, applied in crack detection. [ABSTRACT FROM AUTHOR]

Owing to their degradability, environmental friendliness, and low cost, natural polymers have been widely utilized in the fabrication of triboelectric nanogenerators (TENGs). Chitosan is a natural polymer containing long chains of n-acetylamino glucose. However, the low dielectric constant of pure chitosan films affects their electrical properties. Therefore, in this study, to improve their electrical output performance, the dielectric constant of the films was increased by the incorporation of conductive nanoparticles. Highly transparent Ag/Chitosan films were successfully constructed, and the output performance was improved by varying the concentration of Ag nanoparticles (100–200 nm). At a concentration of 6 wt %, the open-circuit voltage, short-circuit current, and transferred charge reached 74 V, 4.6 μA, and 23.8 nC, respectively, with a maximum output power of 83 μW. Besides, the fabricated friction-based nanogenerator (AC-TENG) lit 20 blue light-emitting diodes (LEDs) and successfully drove a commercial calculator, which verified its practical application potential. Finally, the AC-TENG was used to transmit Morse code, successfully sending the signals "HELP" and "SOS", which might open opportunities in the field of communication application. [ABSTRACT FROM AUTHOR]

(1) Background: Patients with severe physical impairments (spinal cord injury, cerebral palsy, amyotrophic lateral sclerosis) often have limited mobility due to physical limitations, and may even be bedridden all day long, losing the ability to take care of themselves. In more severe cases, the ability to speak may even be lost, making even basic communication very difficult. (2) Methods: This research will design a set of image-assistive communication equipment based on artificial intelligence to solve communication problems of daily needs. Using artificial intelligence for facial positioning, and facial-motion-recognition-generated Morse code, and then translating it into readable characters or commands, it allows users to control computer software by themselves and communicate through wireless networks or a Bluetooth protocol to control environment peripherals. (3) Results: In this study, 23 human-typed data sets were subjected to recognition using fuzzy algorithms. The average recognition rates for expert-generated data and data input by individuals with disabilities were 99.83% and 98.6%, respectively. (4) Conclusions: Through this system, users can express their thoughts and needs through their facial movements, thereby improving their quality of life and having an independent living space. Moreover, the system can be used without touching external switches, greatly improving convenience and safety. [ABSTRACT FROM AUTHOR]

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Flexible tactile sensors have received widespread attention in many potential applications such as intelligence robots, the Internet of Things, and various wearable devices. However, most structure‐enhanced devices are in single‐patterns with limited improvement of sensitivity and working range. Herein, a double‐layered capacitive tactile sensor (DLCTS) with hierarchical microcone arrays, which consists of carbon nanotubes (CNTs) and polydimethylsiloxane (PDMS) is reported. Relying on its intrinsic hierarchical framework and optimized CNTs/PDMS ratios, the DLCTS exhibits an ultrabroad working range of 0–1400 kPa and a high sensitivity of 0.082 kPa−1. Moreover, this sensor shows favorable sensing performance with excellent durability (over 5500 cycles) and a fast response time (≈40 ms). Diverse powerful applications are demonstrated, including active monitoring of human elbow/knee flexion, respiratory state, walking mode, and convenient Morse code communication. It is envisioned that this sensor should be widely used in potential scenarios such as intelligent wearable devices and medical monitoring. [ABSTRACT FROM AUTHOR]

Morse code recognition plays a very important role in the application of human–machine interaction. In this paper, based on the carbon nanotube (CNT) and polyurethane sponge (PUS) composite material, a flexible tactile CNT/PUS sensor with great piezoresistive characteristic is developed for detecting Morse code precisely. Thirty-six types of Morse code, including 26 letters (A–Z) and 10 numbers (0–9), are applied to the sensor. Each Morse code was repeated 60 times, and 2160 (36 × 60) groups of voltage time-sequential signals were collected to construct the dataset. Then, smoothing and normalization methods are used to preprocess and optimize the raw data. Based on that, the long short-term memory (LSTM) model with excellent feature extraction and self-adaptive ability is constructed to precisely recognize different types of Morse code detected by the sensor. The recognition accuracies of the 10-number Morse code, the 26-letter Morse code, and the whole 36-type Morse code are 99.17%, 95.37%, and 93.98%, respectively. Meanwhile, the Gated Recurrent Unit (GRU), Support Vector Machine (SVM), Multi-Layer Perceptron (MLP), and Random Forest (RF) models are built to distinguish the 36-type Morse code (letters of A–Z and numbers of 0–9) based on the same dataset and achieve the accuracies of 91.37%, 88.88%, 87.04%, and 90.97%, respectively, which are all lower than the accuracy of 93.98% based on the LSTM model. All the experimental results show that the CNT/PUS sensor can detect the Morse code’s tactile feature precisely, and the LSTM model has a very efficient property in recognizing Morse code detected by the CNT/PUS sensor.