Small Devices Research Articles

BN SO27 - Articulative Minimally Invasive Surgery and Placement of Anti-reflux Magnetic Surgical Appliance (LINX)

Abstract Background Gastro-oesophageal reflux disease (GORD) is a condition of prolonged retrograde flow of gastric contents into the oesophagus or structures beyond, causing symptoms such as heartburn and regurgitation.1 Laparoscopic Nissen Fundoplication (LNF) has been the surgical gold standard, however its side effects and technical challenges has limited its use to 1% of the GERD population.2 The use of a magnetic surgical appliance (LINX) has recently emerged as a promising treatment in overcoming the limitations of conventional LNF.3 Literature has shown patients aged less than 45 with satisfactory mean contraction amplitude (MAP) of 30mmHg and typical symptoms have favourable outcomes with LINX.3 Method This is a case of a 35-year-old patient presenting with typical reflux symptoms, with satisfactory MAP and high DeMeester score, patulous gastro-oesophageal junction and no hiatus hernia endoscopically. Steps for LINX placement are described in the video and we demonstrate the use of ArtiSential, an articulating laparoscopic instrument that provides better range of motion and angulation comparable to that of a robotic instrument. Results Using a magnetic surgical appliance (LINX) is superior to LNF through preservation of physiological belching and vomiting, reducing surgical time and duration of hospital stay while also scoring highly on quality of life and patient satisfaction.4 Conclusion We would recommend considering the placement of a LINX device in suitable patients as it provides good outcomes on par with LNF and to consider the use of an articulating instrument (ArtiSential) as it provides the surgeon better control and ease in placing a small device laparoscopically.

A Sub-Channel Spatial Homogeneity-Based Channel Estimation Method for Underwater Optical Densely Arrayed MIMO Systems

The limited surface area and structural constraints of small underwater communication devices necessitate a dense placement of transmitting and receiving array elements in optical multiple-input multiple-output (MIMO) systems. The compact layout leads to the formation of sub-channels that exhibit notable spatial correlation and a tendency toward homogeneity. Although sub-channel spatial homogeneity (SSH) may diminish the communication capacity of MIMO systems, it provides a significant advantage by reducing the pilot overhead. In this study, we exploit the inherent SSH and the natural time-domain sparsity of channel impulse response (CIR) in the underwater optical densely arrayed MIMO (UODA-MIMO) system to propose an innovative SSH-based channel estimation (SSH-CE) method. We model the underwater optical CIR at Gbaud rates and integrate it with SSH characteristics. This approach transforms the reconstruction targets of compressive sensing (CS) from conventional CIR samples to prior CIR model parameters and the fitting residuals of the homogeneous sub-channels, reducing the pilot overhead. The simulation results of photon tracing for UODA-MIMO sub-channels in turbid harbor water indicate a monotonic, exponential decay in CIR at Gbaud rates, with transmission delays exceeding 5 nanoseconds for distances over 8 m. Moreover, the correlation coefficients among sub-channels reach a minimum of 0.975, confirming the presence of SSH in UODA-MIMO systems. In comparison to existing CS methods that rely on known sparsity, sparsity adaptation, and the structural sparsity of MIMO channels, the SSH-CE method achieves a lower degree of sparsity in reconstruction targets and a reduced lower bound for pilot requirements under the SPARK criterion. Specifically, the SSH-CE method achieves a reduction in the pilot overhead for reconstructing Nt sub-channels of K-sparse to 2Nt irrespective of CIR residual compensation.

Source-detector trajectory optimization for FOV extension in dental CBCT imaging

In dental imaging, Cone Beam Computed Tomography (CBCT) is a widely used imaging modality for diagnosis and treatment planning. Small dental scanning units are the most popular due to their cost-effectiveness. However, these small systems have the limitation of a small field of view (FOV) as the source and detector move at a limited angle in a circular path. This often limits the FOV size. In this study, we addressed this issue by modifying the source-detector trajectory of the small dental device. The main goal of this study was to extend the FOV algorithmically by acquiring projection data with optimal projection angulation and isocenter location rather than upgrading any physical parts of the device. A novel algorithm to implement a Volume of Interest (VOI) guided trajectory is developed in this study based on the small dental imaging device's geometry. In addition, this algorithm is fused with a previously developed off-axis scanning method which uses an elliptical trajectory, to compensate for the existing constraints and to further extend the FOV. A comparison with standard circular trajectory is performed. The FOV of such a standard trajectory is a circle of 11 cm diameter in the axial plane. The proposed novel trajectory extends the FOV significantly and a maximum FOV of 19.5 cm is achieved with the Structural Similarity Index Measure (SSIM) score ranging between (≈98-99%) in different VOIs. The study results indicate that the proposed source-detector trajectory can extend dental imaging FOV and increase imaging performance, which ultimately results in more precise diagnosis and enhanced patient outcomes.

Phase Change Thermal Interface Materials with Interface Adaptability and Self-Healing Properties

Thermal stress resulting from excessive temperatures is a major cause of electronic device failure. In this work, with easy installation and good interface adaptability, Phase Change Thermal Interface Materials (PCTIMs) which possess high thermal conductivity were prepared. By incorporating phase change material stearic acid (SA) into the thermal interface material, the instantaneous heat absorption during the solid-liquid phase transition of SA effectively alleviates the problem of instantaneous high heat flux impacting electronic devices. Additionally, the solid-liquid transition reduces the modulus of TIMs, thereby minimizing the contact thermal resistance between the heat source and the heat sink during mechanical installation. To further enhance performance, the thermal interface material utilizes a dynamically cross-linked polyolefin elastomer (POE) with borate bonds, which effectively restricts the flow of SA even at its phase change point due to the three-dimensional cross-linked framework. By constructing a thermal conductive network using carbon fibers and aluminum nitride of different dimensions, the thermal conductivity of the thermal interface material reached 1.82 W∙m−1K−1 with a filler content of only 30 vol% . At 70°C, with a force of 50 N applied to a sample area of 400 mm², the contact thermal resistance was only 2.39×10−4K∙m2W−1. Furthermore, the PCTIMs exhibits excellent self-healing ability under thermal conditions, assuring the permanent encapsulation of small electronic devices.

Does preprocedural ultrasound prior to lumbar neuraxial anesthesia or analgesia increase first-pass success in adults with obesity? A systematic review.

Preprocedural ultrasound (PPU) reduces the risk of technical failure in non-obese patients and when technical difficulty is predicted. We conducted this review to determine if PPU improves first-pass needle insertion success for neuraxial anesthesia in patients with obesity. We conducted a systematic review without meta-analysis, due to the small number of included studies. The study protocol was registered (PROSPERO: CRD42022368271). We conducted searches in MEDLINE, Embase, PubMed, and Cochrane Library from January 1, 1980 to October 1, 2022 for peer-reviewed randomized controlled or observational studies comparing PPU versus landmark techniques in patients with body mass index >30 kg/m2. The quality of evidence was assessed using the revised Cochrane risk-of-bias tool for randomized trials and Grading of Recommendations Assessment, Development, and Evaluation approach. There were nine randomized controlled studies, comprising 866 patients having lumbo-sacral neuraxial techniques. Three studies utilized a small handheld ultrasound device called Accuro™ and six utilized non-handheld ultrasound devices. Certainty of evidence was low for improving the first-pass success rate. There was evidence (moderate certainty) that PPU decreased number of passes, increased first insertion attempt success, and reduced number of insertion attempts. There was no evidence that PPU affected identifying time, needling time, or overall procedural time. There was no evidence that PPU influenced procedural failure rate (very low certainty evidence) and insufficient evidence to suggest that artificial intelligence-supported handheld devices were superior to conventional ultrasound devices. In patients with obesity, there is evidence of very-low to moderate certainty that PPU improves markers of insertion success, with no indication of increased adverse effects. PPU should be used to reduce attempts. Further studies adhering to standardized outcome definitions are required for definitive recommendations. The study protocol was registered on the International Prospective Register of Systematic Reviews (PROSPERO: CRD42022368271).

Do-it-yourself flavored capsule cigarettes: Exploiting potential regulatory loopholes?

Capsule cigarettes allow users to crush liquid-filled capsules to release flavors into cigarettes' filters. New devices are emerging across the globe that allow people who smoke to circumvent tobacco flavor restrictions via injectable capsules. This study examined TikTok videos marketing flavored capsule injector devices. TikTok videos (n = 832) posted worldwide between July 6, 2021, and December 28, 2023, that used hashtags #injectorflavor, #flavourclickball, #flavorball, and #injectorballcigarette were collected using a TikTok application programing interface. A codebook was developed using a systematic iterative approach, identifying six codes: flavor capsules, promotes flavors (i.e., fruit, mint or menthol flavors, non-alcoholic drinks, alcoholic drinks), demonstrates how to use or refill large injector devices, demonstrates how to use small convenient devices, includes music (any or English-language). Two independent coders annotated all videos. Overall, 88.3% (n=735) of the videos displayed flavor capsules and had been viewed more than 72 million times. Half (51.6%) of the videos demonstrated how to use large box-shaped devices to inject capsules into the filter of a cigarette, and 15.0% of the videos showed how to do this with smaller, more convenient devices. Flavors including fruit (35.5%), menthol/mint (27.8%), non-alcoholic drinks (21.9%), and alcoholic drinks (11.6%) were used to promote these capsules. Most videos (85.6%) were uploaded by sellers on "TikTok shop." TikTok accounts are promoting injectable capsule devices that circumvent flavored tobacco sales restrictions. Policy makers, tobacco control advocates, and public health practitioners should be aware of such marketing to inform regulation and develop prevention strategies. Our findings identified an emerging product that can encourage circumvention of flavor restriction policies. Regulators, policy makers, public health practitioners, researchers, and advocates should be aware of such products to inform regulation and develop prevention strategies. Given the potential for these products to reduce the intended effects of flavored tobacco sales restrictions, policy makers must be poised to address materials that consumers use to create their own flavored tobacco products, including flavor capsules designed to be inserted into cigarettes.

An Energy-Efficient Dynamic Feedback Image Signal Processor for Three-Dimensional Time-of-Flight Sensors.

With the recent prominence of artificial intelligence (AI) technology, various research outcomes and applications in the field of image recognition and processing utilizing AI have been continuously emerging. In particular, the domain of object recognition using 3D time-of-flight (ToF) sensors has been actively researched, often in conjunction with augmented reality (AR) and virtual reality (VR). However, for more precise analysis, high-quality images are required, necessitating significantly larger parameters and computations. These requirements can pose challenges, especially in developing AR and VR technologies for low-power portable devices. Therefore, we propose a dynamic feedback configuration image signal processor (ISP) for 3D ToF sensors. The ISP achieves both accuracy and energy efficiency through dynamic feedback. The proposed ISP employs dynamic area extraction to perform computations and post-processing only for pixels within the valid area used by the application in each frame. Additionally, it uses dynamic resolution to determine and apply the appropriate resolution for each frame. This approach enhances energy efficiency by avoiding the processing of all sensor data while maintaining or surpassing accuracy levels. Furthermore, These functionalities are designed for hardware-efficient implementation, improving processing speed and minimizing power consumption. The results show a maximum performance of 178 fps and a high energy efficiency of up to 123.15 fps/W. When connected to the hand pose estimation (HPE) accelerator, it demonstrates an average mean squared error (MSE) of 10.03 mm, surpassing the baseline ISP value of 20.25 mm. Therefore, the proposed ISP can be effectively utilized in low-power, small form-factor devices.

Pathobiological characterization of pulmonary hypertension associated with heart failure with preserved ejection fraction

Abstract Introduction Heart failure with preserved ejection fraction (HFpEF) is an age-related cardiometabolic disease associated with vascular inflammation in cardiac tissue, pulmonary congestion and right ventricular dysfunction. Patients with HFpEF often develop pulmonary hypertension (PH) and right ventricular (RV) hypertrophy. Pulmonary vascular remodeling contributes to combined post- and precapillary PH (CpcPH), which is associated with worse outcome in humans. A recently developed meta-inflammatory murine HFpEF model approximates the characteristics of human HFpEF. Herein, HFpEF is induced by metabolic (high-fat diet (HFD)) and hypertensive stress (inhibition of constitutive NO synthase by Nω-nitro-1-arginomethyl ester (L-NAME)) over a 12-week period of time. With a focus on PH, we have developed a 'three-hit' model based on this model with a supplementary 21- or 42-day hypoxia phase (HFpEF-CpcPH). Methods Adult C57BL/6N mice were fed HFD for 15 or 18 weeks and supplied with L-NAME (0,5g/L or 1g/L) via drinking water, including a final period of 21 or 42 days, respectively, of hypoxia (normobaric, 10 % oxygen) or normoxia. Transthoracic echocardiography was performed using a small animal ultrasound device (Vevo 3100, Visual Sonics) and measurement of right ventricular systolic pressure (RVSP) using a Millar® pressure catheter (Mil-SPR-1000) inserted into the right ventricle. Right ventricular hypertrophy was measured as the ratio of the wet weight of the right ventricle to the left ventricle including the septum (RV/LV+S). Results Administration of HFD and L-NAME had no significant effect on RVSP in either HFpEF-normoxia group (15 weeks (n=8) or 18 weeks (n=5)) compared to the control group (n=8, n=5). 21 days of hypoxia increased RV systolic pressure (RVSP) to 37.05±1.6 (PH, n=8) and 40.33±0.87 mmHg (HFpEF-CpcPH, n=8) respectively, while 42 days of hypoxia caused no further increase (35.1±3.5 mmHg (PH, n=5) and 35.24±3.47 mmgHg (HFpEF-CpcPH, n=4)), respectively. RV hypertrophy (RV/LV+S) was significantly increased after 21 days of hypoxia in HFpEF-CpcPH compared to HFpEF (n=8) (34.42±1.75 vs. 24.93±1.1). Again, 42 days of hypoxia did not lead to a further increase in RV hypertrophy (35.2±3.9 vs. 25.80±4.39) in HFpEF-CpcPH, even though there was a significant difference compared to the HFpEF group. As expected, the heart weight/body weight ratio was significantly increased in HFpEF-CpcPH compared to HFpEF at both time points. However, mice under the prolonged hypoxia phase showed a significantly greater decrease in body weight, which complicates the interpretation of the results. Conclusion In summary, we could show that in the meta-inflammatory HFpEF model no significant PH can be observed within the investigated periods of time. However, a 21 day hypoxia phase was sufficient to induce a HFpEF-CpcPH phenotype. This model provides an important basis to develop new therapeutic approaches.

Using Animation to Address Disparities in Kidney Transplantation

ABSTRACT This essay reviews an arts-based project based in Buffalo, New York, seeking to educate patients with kidney failure and their social network about the transplantation process. Through a multi-phase arts-based research project, informed by a community-based steering committee and key stakeholders, 33 educational animated videos were developed and tested for efficacy in samples of diverse patients at a regional transplant center. Animation was chosen for its potential to better explain health concepts more sensibly to patients and support knowledge dissemination to their social network, who may donate a kidney or support a recipient or donor. The videos are 2D, short in duration, and designed for easy viewing on small devices using characters, scenes, narration, and movement. Aesthetic choices reinforce learning: characters have confident posture, memorable features (e.g. hair style, clothing color) with minimal detail, and model diverse races, ethnicities, gender, and body types. Scenes feature light backgrounds, illuminate main images, and are as large as possible for small screens. Narration is slow, calm, and uses strategic pauses to introduce concepts. Movement is selective to reinforce the message (signaling). The animation was guided by self-efficacy theory and the cognitive theory of multimedia learning. Findings to date indicate promising results with respect to patient knowledge and the feasibility of using animation to address disparities in kidney transplantation. Figures illustrate the evolution of the project and provide examples of the art used to capture a given aspect of the transplantation process.

Hybrid Planar Copolymer Membranes with Dual Functionality against Bacteria Growth.

Antibacterial surfaces can be classified into two categories: passive surfaces, which repel bacteria by affecting surface wettability, and active surfaces, which have bactericidal properties that disrupt cell membranes upon contact. With the increasing demand for effective antibacterial solutions that combine these properties, advanced strategies are concentrating on developing surfaces with dual antimicrobial functionalities. Here, we present surfaces with nanotexture resulting from the phase separation of two different amphiphilic block copolymers displaying efficient dual functionality against bacteria growth. This approach combines the inherent antifouling properties of poly(ethylene oxide) as the hydrophilic domain of one copolymer with the antimicrobial effect of a peptide covalently attached to the hydrophilic domain of the second copolymer. The planar membranes are generated by self-assembly of the amphiphilic copolymer mixture deposited by Langmuir-Blodgett and Langmuir-Schaffer methods on a solid support, followed by covalent attachment of the antimicrobial peptides to one of the copolymers, specifically functionalized. Combining both copolymers, in terms of their properties and functionalities on the same surface, significantly limitsEscherichia colibiofilm formation and effectively eradicates bacteria during short-term incubation. While such multifunctional antimicrobial planar polymer membranes show promising potential in the design of fine coatings for small surgical or implantable devices, they are not limited to this application. Their use can be completely changed by attaching other active molecules or assemblies to induce specific multifunctionality for the targeted application.

Super Low Profile 5G mmWave Highly Isolated MIMO Antenna with 360∘ Pattern Diversity for Smart City IoT and Vehicular Communication

This study introduces a planar folded super low profile 5G mmWave monopole antenna for small IoT devices with superior efficiency and gain. Low-loss Rogers RT-5880 substrate material has been utilized to achieve higher efficiency, gain, and diversity performance in a relatively compact size. The unit element planar monopole antenna has been designed within 6.15×5.13×0.8mm3 with a partial ground. Four unit element antenna was orthogonally arranged on alternating sides of the substrate plane with narrow inter-component spacing in the multiple input multiple output (MIMO) system. The integration of the double negative (DNG) metamaterial array on the antenna led to a cumulative improvement in the overall performance of the antenna, which includes gain, efficiency, and isolation. The minimum isolation of the antenna increased by 11 dB with substrate-loaded metamaterial. The proposed MIMO antenna model with substrate-loaded metamaterial demonstrates 8 GHz instantaneous bandwidth (33.1 GHz - 41.1 GHz), 0.001 envelope correlation coefficient (ECC), diversity gain (DG) greater than 9.99 dB, channel capacity loss (CCL) less than 0.2bits/s/Hz, and a total active reflection coefficient (TARC) of 25 dB, which suggests that the diversity characteristics of the MIMO antenna system is impressive. Moreover, a densely packed 12-element antenna model has been introduced in this study with 360∘ pattern diversity, capable of receiving signals from any direction. Three 4-element MIMO systems have been arranged in an architecture to develop the 12-element MIMO system, and the size of the 12-element MIMO architecture is 15×15×15mm3. Despite having this compact size and dense packing, the 12-element MIMO antenna model shows similar diversity performance as the 4-element antenna model. Analog equivalent circuit models or resistor-inductor-capacitor (RLC) equivalent systems for the antenna models were created. A concept of a 128-element massive MIMO antenna has been presented to support the end devices, creating an application scenario of an IoT-interconnected smart city.

Development on Mechatronics Based RFID Attendance System with Artificial Intelligence

An RFID attendance system is a system that uses radio frequency identification (RFID) technology to track and record attendance. RFID tags are small electronic devices that store a unique identifier. When an RFID tag is brought near an RFID reader, the reader can read the identifier and send it to a computer. The computer can then use the identifier to look up the corresponding person's attendance record. An RFID attendance system is an automated system that uses RFID (Radio Frequency Identification) technology to track and record employee attendance. It consists of two main components: RFID tags and RFID readers. RFID tags are small electronic devices that store a unique identifier. They are typically attached to employee badges or cards. RFID readers are devices that can read the unique identifiers stored on RFID tags. They are typically installed at entry points to buildings or rooms. When an employee enters a building or room, they must present their RFID badge or card to an RFID reader. The reader will read the unique identifier stored on the tag and send it to a computer. The computer will then use the identifier to look up the employee's attendance record. If the employee is not already clocked in, they will be clocked in. If the employee is already clocked in, they will be clocked out.

Ultra-broadband all-optical nonlinear activation function enabled by MoTe2/optical waveguide integrated devices

All-optical nonlinear activation functions (NAFs) are crucial for enabling rapid optical neural networks (ONNs). As linear matrix computation advances in integrated ONNs, on-chip all-optical NAFs face challenges such as limited integration, high latency, substantial power consumption, and a high activation threshold. In this work, we develop an integrated nonlinear optical activator based on the butt-coupling integration of two-dimensional (2D) MoTe2 and optical waveguides (OWGs). The activator exhibits an ultra-broadband response from visible to near-infrared wavelength, a low activation threshold of 0.94 μW, a small device size (~50 µm2), an ultra-fast response rate (2.08 THz), and high-density integration. The excellent nonlinear effects and broadband response of 2D materials have been utilized to create all-optical NAFs. These activators were applied to simulate MNIST handwritten digit recognition, achieving an accuracy of 97.6%. The results underscore the potential application of this approach in ONNs. Moreover, the classification of more intricate CIFAR-10 images demonstrated a generalizable accuracy of 94.6%. The present nonlinear activator promises a general platform for three-dimensional (3D) ultra-broadband ONNs with dense integration and low activation thresholds by integrating a variety of strong nonlinear optical (NLO) materials (e.g., 2D materials) and OWGs in glass.

Vibroacoustic characterization of small woven fabrics

This study is aimed to analyze the vibroacoustic behaviour of woven fabrics utilized in small acoustic devices for ingress protection. We first concentrate on predicting and describing the vibration behaviour of the woven fabric structure through flip around, since lumped modelling comes first. A vibration experiment is also conducted to measure the motion of the woven fabric structure under external excitation to validate the modelling. The numerical model is then employed to simulate the vibroacoustic behaviour of the woven fabric via transmission loss calculation; the simulation is then compared with transmission loss measurement based on the four-microphone method. This research demonstrates that despite some limitations, both the numerical and lumped models show a good degree of accuracy in predicting the vibration of the woven structure; the numerical model also performs well in vibroacoustic modelling.

The MnAl-alloy nanoparticles incorporated PVDF-based piezoelectric nanogenerator as a self-powered real-time pedometer sensor

This study introduces a flexible, sensitive, and cost-effective hybrid piezoelectric nanogenerator (PENG) by integrating MnAl-alloy nanoparticles into a poly (vinylidene fluoride) (PVDF) nanocomposite film. The MnAl-alloy nanoparticles serve as a nucleating agent for promoting the formation of the electroactive β-phase. It is observed that the electroactive β-phase, dielectric permittivity, saturation polarization, and output performance of the device improve with the incorporation of the MnAl-alloy nanoparticles up to 7.5 wt. % in the PVDF matrix. Hence, in this work, we report a MnAl-alloy-based optimized piezoelectric nanogenerator device using a free-standing nanofiber mat (7.5 wt. % MnAl-alloy) prepared by the electrospinning technique. The as-fabricated piezoelectric nanogenerator effectively channels charges generated by mechanical stress to the electrodes, resulting in an impressive output voltage of approximately 16 V and an output current of around 7.1 μA, yielding a power of 47 μW across 4.5 MΩ resistor. Furthermore, energy harvesting from human movements such as jogging, knee bending, and walking is demonstrated for practical application. A piezo potential of approximately 8 V generated during walking showcases the development of a self-powered pedometer. Furthermore, tapping the PENG charges a capacitor of 0.1 μF up to approximately 1 V, demonstrating the potential application for the power up of small portable electronic devices.

A novel plasma source concept for negative ion generation in neutral beam injectors for fusion applications

Abstract A low-temperature plasma can very well be confined by a simple magnetic dipole, such as in the Van Allen belts of Earth’s magnetoshpere. This configuration can be reproduced in laboratory as a small experimental device, designed in such a way that the magnetic field lines remain within a vacuum-tight container and are virtually not intercepted by the container wall. In this paper we propose to use a dipole field for the realization of an efficient negative Ion source. To this purpose, we analyze the plasma confinement capabilities of such plasma source, in order to assess the equilibrium pressure and estimate the particle trajectories and drifts.

Multi-energy harvesting: Integrating contact-mode and slide-mode triboelectric nanogenerators, and solar technologies for efficient power generation in small electronic

Harvesting energy from the environment is getting more attention daily to drive small electronics. This paper presents a hybrid energy harvesting module that uses contact-mode triboelectric nanogenerator, slide-mode nanogenerator, and solar energy to generate electrical power. The fabricated module has three parts, i.e., the base part operating in triboelectric contact mode, the rotary part employing lateral sliding triboelectricity, and solar cells for harnessing sunlight. The 3D designed module parts have been fabricated using 3D printer and laser cutting machine. Subsequently, the parts were assembled by applying triboelectric (Aluminum and Kapton) material onto them. The triboelectric contact mode generated 0.57 µW of electric power achieving power density achieved 57 µWm−2 at the contact area of 100 cm2. Electric power delivered by triboelectrification of the rotary part was 117 µW, whereas the power density was recorded as 232.6 µWm−2 at the contact area 503.36 cm2, and power delivered by solar cells was 66.64 mW. The designed module successfully delivered power to small electronic devices such as electronic thermometers, digital calculators, digital clocks, and 25 green-coloured LEDs. The implications of these findings suggest that such a hybrid module can significantly extend the operational life and independence of small-scale electronics, making it a promising solution for remote sensing, wearable technology, and IoT devices.

Recycling lithium-ion batteries: A review of current status and future directions

Lithium-ion batteries (LIBs) have become a widely adopted energy source for various electrical devices, ranging from small devices to large machines, such as cell phones, and electric vehicles (EVs). The increasing number of EVs, and other electrical devices has led to the enormous amount of discarded spent LIBs into the landfill. The amount of LIB waste generated in 2019 alone from EVs was 500,000 tons. This amount is expected to reach 8,000,000 tons by 2040. Globally, only 5 % of discarded spent LIBs is presently being recycled. The need to recycle LIBs stems from the desire to conserve raw materials, and save cost. Also, LIBs comprise heavy metals (Ni, Li, Co, Cu, Mn, Fe, and Al), and hazardous chemicals, which cause serious environmental hazards and threaten human lives; thus, pointing out the need to recycle LIBs. This work reviewed different recycling techniques and, the latest technological advancements in pretreatment methods, hydrometallurgy, pyrometallurgy, and direct recycling methods. Also, future perspectives and prospects are provided herein.

A Direct Current Self-Sustained Moisture-Electric Generator with 1D/2D Hierarchical Nanostructure for Continuous Operation of Off-Grid Electronics.

Ubiquitous moisture is a colossal reservoir of clean energy, and the emergence of moisture-electric generators (MEGs) is expected to provide direct power support for off-grid electronic devices anytime and anywhere. However, most MEGs rely on auxiliary energy storage devices and rectifier circuits to drive small electronic devices, which hinder scalability and widespread deployment, and the development of direct current (DC) MEGs with high power output that can directly drive off-grid electronic devices is highly promising but challenging. Herein, a self-sustained moisture-electric generator (SMEG) with a hierarchical nanostructure based on one-dimensional (1D) negatively charged nanofibers and two-dimensional (2D) conductive nanosheets was demonstrated to generate continuous DC electricity from atmospheric humidity. Sulfation of bacterial cellulose nanofibers lowers the surface potential and increases the surface charge energy, and reduced graphene oxide (rGO) provides a conduction pathway for electrons. The hierarchical nanostructures constructed by the combination of 1D nanofibers and 2D nanosheets endow the SMEG with self-sustained moisture gradients and structural anisotropy, which force the generation of a pseudocurrent. This combination also constructs microcapacitors that further enhance the moisture-electric power output. The SMEG can generate a continuous voltage in excess of 0.54 V for over 2160 h, with a power density of about 822 μW cm-3, demonstrating excellent operational durability. This research provides a feasible solution for the development of sustainable, versatile, and efficient power supplies for off-grid self-powered devices.

Applications of vibrational phenomena to evaluate the effect of hydrogen solution on the elasticity and fatigue properties of industrial metal plates

Understanding resonance phenomena in materials is crucial in many fields, from controlling noise in small mobile devices to designing seismic-safe large structures or in energy harvesting. Resonance depends on material elasticity and its shape, influenced by temperature. While controlling elastic properties can control vibrations, seeking practical alternatives is essential. This research focuses on introducing hydrogen into industrial metal materials as a method to control resonance conditions, which is particularly relevant in the context of the upcoming hydrogen society. Controlled amounts of hydrogen were introduced to industrial metal plates (Ti, W) using electrochemical methods to investigate changes in their resonance characteristics. The results indicate that the introduction of hydrogen into Ti resulted in a maximum 20% reduction in Young's modulus, while W exhibited a 10% decrease. Additionally, the recovery of their modulus by hydrogen desorption was confirmed. This confirms that the control of hydrogen allows the manipulation of the modulus of elasticity at constant temperature, controlling the resonance without changing the dimensions. Furthermore, similar evaluations were performed on high hardness steel. The results showed fatigue failure due to vibration, increased Young's modulus with the introduction of hydrogen, and an observed trend toward decreased life to failure.