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Abstract Pursuit of improved living quality has stimulated great demand for high-performance conformal healthcare devices in modern human society. However, manufacturing of efficient, comfortable and stretchable biomedical apparatus faces huge challenges using traditional materials. Liquid metals (LMs) show remarkable potential to solve this problem due to their extraordinary biocompatibility, stretchability, thermal and electrical conductivity. In recent years, tremendous explorations have attempted to make stretchable biomedical devices with LMs. Herein, we review the stretchable LM-based biomedical devices on the topics of disease treatment and human function augmenting. The representative and up-to-date neural interfaces, alloy cement, e-vessels, soft heaters, exoskeletons, and e-skins are summarized. The existing issues of LMs applied for biomedical devices are also discussed. This review can provide guidance for the follow-up research in LM-based biomedical devices.

A low-profile, dual-band tag antenna (39 mm $\times 39$ mm $\times 1.38$ mm), which is loaded with a circular patch at the central region for frequency tuning purposes, has been proposed for on-metal applications that operate in the Lower European (LEu) and the North American (NA) UHF-RFID passbands. The antenna itself consists of a square ring as well as a hexagonal ring, all of which can be fully made on a single-layer substrate, and they are concentrically stacked for generating a stable broadside radiation pattern on metal surface. The dimensions of the rings can be adjusted to achieve efficient wide-range frequency tuning capability, with conjugate impedance matching over the two operating frequencies. The proposed tag antenna is simple, and it does not require the use of other complex tuning mechanisms. Independent frequency tuning is possible over the two passbands. With 4W Effective Isotropic Radiated Power (EIRP), the maximum measured realized gain is −5.69 dBi at 868 MHz in the LEu UHF RFID band while −5.18 dBi at 921 MHz in the NA UHF RFID band. This configuration enables extended read ranges of 8 m and 9 m for the LEu and NA UHF RFID passbands, respectively. A detailed analysis was conducted to understand the resonance characteristics, and a Transmission Line (TL) model was constructed to facilitate the design of the tag antenna. It is important to highlight that the two tag resonant frequencies are stable and not much affected by the presence of the backing metallic object. Dual-band UHF RFID tags are useful for cross-national tracking and identification applications, where their systems may be operating in two different passbands without compatibility.

As a major contributor to global energy consumption and greenhouse gas emissions, the building sector is crucial in shaping energy and climate change policies. Understanding building energy consumption is essential for developing effective policies, and comprehensive datasets and analyses are increasingly important. This paper outlines a structured methodology for developing a sustainability assessment index for building energy efficiency retrofits throughout a building’s life cycle, covering the design, construction, use, and out-of-use phases. It highlights the interdependencies among these phases, with the design plan influencing energy efficiency and material selection, the construction plan ensuring these goals are met, and the plans for energy management, demolition, and resource recovery focusing on sustainable practices. The keys to energy-efficient retrofits are sustainable materials, energy-efficient equipment, and green technologies, which help reduce energy consumption, emissions, and operating costs. Oversight and regulation are necessary to maintain standards. This research combines a literature review, surveys, interviews, the Delphi method, and an analytic hierarchy process (AHP) to develop a comprehensive evaluation system, categorizing 20 factors across a building’s life cycle and assigning weights based on environmental, economic, and social dimensions. The system provides a scientific basis for assessing the sustainability of energy efficiency programs, validated through consistency testing.

Autoclaved aerated concrete (AAC) has gained widespread acceptance in construction as a lightweight solution for exterior and interior walls. However, traditional steel-reinforced autoclaved aerated concrete (SR-AAC) has limitations, including concerns over its ductility and difficulty in cutting during installation. The steel reinforcement also has high embodied carbon that does not align with the actions in the construction section to reach carbon neutrality shortly. This study investigated the material properties and mechanical performances of factory-produced fiber-reinforced autoclaved aerated concrete (FR-AAC) panels, aiming to examine their potential as an alternative solution. Full-scale FR-AAC panels with thicknesses of 100 mm, 150 mm, and 200 mm were manufactured and tested. Some panels were down-sampled to determine the dry density, water absorption, compressive strength, and flexural strength of the material, while the mechanical performances were evaluated through static and impact loading tests. The results showed that the average dry density and absorption of the FR-AAC material are 533 kg/m3 and 63%, respectively, with compressive strengths up to 3.79 MPa and flexural strengths reaching 0.97 MPa. All six panels tested under static uniformly distributed loading exceeded the self-weight limit by a factor of 1.5, satisfying standard requirements for load-bearing capacity. However, the brittle failure modes observed in some tests raise potential health and safety concerns. In contrast, the impact tests revealed that the panels have acceptable performances with the inclusion of fibers.

Abstract This paper presents a 35.0 × 35.0 × 2.7 mm3 compact, low-profile, and lightweight wearable antenna for on-body wireless power transfer. The proposed antenna can be easily printed on a piece of flexible tattoo paper and transformed onto a PDMS substrate, making the entire antenna structure conform to the human body for achieving a better user experience. Here, a layer of frequency selective surface (FSS) is inserted in between the antenna and human tissue, which has successfully reduced the loading effects of the tissue, with 13.8 dB improvement on the antenna gain. Also, the operating frequency of the rectenna is not affected much by deformation. To maximize the RF-DC conversion efficiency, a matching loop, a matching stub, and two coupled lines are integrated with the antenna for tuning the rectenna so that a wide bandwidth (~ 24%) can be achieved without the use of any external matching networks. Measurement results show that the proposed rectenna can achieve a maximum conversion efficiency of 59.0% with an input power of 5.75 μW/cm2 and can even exceed 40% for a low input power of 1.0 μW/cm2 with a 20 kΩ resistive load, while many other reported rectennas can only achieve a high PCE at a high power density level, which is not always practical for a wearable antenna.

ABSTRACT The urgent need for new antibacterial drugs arises from the emergence of bacterial multidrug resistance due to antibiotic overuse. Antimicrobial peptides, crucial components of innate immunity in animals and plants, exhibit effectiveness against multidrug-resistant bacteria while minimizing the development of drug resistance. In this study, the antibacterial peptide BsR1, comprising 21 amino acids, was finalized by predicting the active site of an antifungal gene and sequence optimization. BsR1 displayed broad-spectrum antibacterial activities against diverse Gram-positive and Gram-negative bacteria, with a low minimum inhibitory concentration of 4.25–17 μM. Stability experiments demonstrated that BsR1 has high resistance to thermal, ultraviolet, and acid-base conditions, while revealing increased sensitivity to divalent ions Ca2+ and Mg2+. The mode of action of BsR1 involved cell membrane damage, leading to bacterial cell structure disruption and subsequent death. Secondary structure prediction indicated a linear helical conformation with a positive charge of +7.5, facilitating its interaction with the target cell membrane. BsR1 exhibited excellent biological safety, as it did not induce necrosis in tobacco leaves, and the low observed hemolytic effect on mammalian cells with a value of 3.26%. Additionally, BsR1 demonstrated the ability to enhance disease resistance in rice and effectively curbed the spread of rice bacterial blight. This research presents BsR1 as a novel approach and potential medication in the development of antibacterial drugs, offering a valuable tool in combating pathogenic microorganisms, particularly in plants. IMPORTANCE This study addresses the critical need for new antibacterial drugs in the face of bacterial multidrug resistance resulting from antibiotic overuse. It highlights the significance of antimicrobial peptides as essential components of innate immunity in animals and plants, which have been proven effective against multidrug-resistant bacteria and are difficult to develop resistance against. This study successfully synthesizes a broad-spectrum antibacterial peptide, BsR1, with strong inhibitory activities against various Gram-positive and Gram-negative bacteria. BsR1 demonstrates favorable stability and a mode of action that damages bacterial cell membranes, leading to cell death. It also exhibits biological safety and shows potential in enhancing disease resistance in rice. This research offers a novel approach and potential medication for antibacterial drug development, presenting a valuable tool in combating pathogenic microorganisms, particularly in plants.

There are many practical engineering problems in the hydraulic fracturing of crack reservoirs, such as the maintenance of wall rock, the efficiency of reservoir's permeability and the prevention of groundwater hazard. In this paper, the control mechanism of fracture pressure under multi-field and multi-phase coupling in horizontal wells and the fracturing evaluation of crack reservoirs were studied deeply to address these issues. Firstly, the transformation effect of the perforation concentration on the original stress field was analyzed. Secondly, the permeability of fracturing fluid in the primary fractures was considered. Finally, based on the strength principle of fracture mechanics, the calculation model of fracture pressure for horizontal wells in the reservoir was established. Furthermore, the influence of the spatial geometric parameters of the fracture field on the initiation pressure was analyzed, and the concept of the characteristic parameters of the fracture field was proposed. The results indicate that the coupling of fluid-solid multiphase in the fields of perforation stress, fracturing fluid permeation and original fracture leads to horizontal well hydraulic fracturing, and the characteristic parameter of fracture field plays a leading role in controlling the initiation pressure. Among them, the biggest controlling factor on initiation pressure is crack width. When the crack width of reservoir is within 200–700 μm, hydraulic fracturing has practical significance for improving reservoir permeability, which solves the problem about the quantification of initiation pressure and the fracturing evaluation in crack reservoirs. By calculating initiation pressure and contrasting to engineering example, it is found that the productivity of the sandstone reservoir is very ideal in the H8 section of the eastern Sulige gas field after hydraulic fracturing, and the theoretical value of fracture initiation pressure is in good agreement with the measured value, which verifies the correctness of the model. These can provide theoretical basis for fracturing construction of horizontal wells.

Purpose. To determine the incidence of anterior chamber (AC) instability during phacoemulsification (phaco) combined with intraocular lens implantation and investigate its effect on intraocular tissues. Methods. Among the 248 enrolled eyes, 121 and 127 eyes were categorized into the irrigation and nonirrigation groups, respectively, depending on the use of a self-made anterior chamber maintainer (ACM) during phaco. AC stability was evaluated using operating microscopy and intraoperative optical coherence tomography (iOCT). Slit-lamp examination of AC flare and cells was performed 1 day postoperatively. Corrected distance visual acuity (CDVA), intraocular pressure (IOP), endothelial cell density (ECD), central corneal thickness (CCT), posterior vitreous detachment (PVD), and central foveal thickness (CFT) were evaluated preoperatively and at 1 week, 1 month, and 3 months postoperatively. Results. There was good consistency in AC stability evaluation between operating microscopy and iOCT. The incidence of AC instability was significantly different between groups after the phaco and irrigation/aspiration tips were withdrawn from the AC P0.05. At 1 month and 3 months postoperatively, PVD occurred in 8 (16.3%) and 14 (28.6%) eyes and in 22 (40.7%) and 37 (68.5%) eyes in the irrigation and nonirrigation groups, respectively (P = 0.006 and P

One of the most effective ways to improve building energy efficiency and consumption is to increase the thermal insulation of the building envelope and reduce the heat loss through walls. A new type of thermal insulation wall panel, consisting of a lightweight assembled exterior wall panel, was investigated in this research through experimental and numerical analyses. The feasibility of achieving the anticipated thermal performance through finite element modeling using ABAQUS® was verified. Good agreement between numerical simulation and experimental measurement was found, and the accuracy is 98.8%. To further reduce the heat transfer coefficient (U-value) of the panel to improve its thermal performance, parametric analyses were conducted utilizing the validated finite element model. The simulation shows that changing the insulation material is the best option, and the U-value reduction percentage reached 13.2%. Moreover, the combination of reducing the number of steel studs, decreasing the size of steel studs, implementing the opening of the light-gauge steel, and improving the insulation material led to a 23.7% reduction in the U-value at 0.695 W·m−2·K−1.

We report an extended surface technique that utilises micro-fin arrays to enhance the heat transfer performance in the microchannels at Reynolds number ranging from 400 to 1000. Three different types of microfins namely Case A (cylindrical micro-fin), Case B (offset cylindrical micro-fin) and Case C (diverge cylindrical micro-fin) are designed. A comparative study between the three cases and bare rectangular microchannel was conducted. The technique enhances the thermal dissipation rate while keeping the pressure drop at a satisfactory level through proper design configurations. Numerical study has been performed in order to elucidate the single phase heat transfer phenomena in the present study.

Amid the increasing demand for advanced gas sensing technologies, particularly for ammonia gas detection, this study presents an innovative solution for far-field sensing at room temperature. Widely used in various industrial applications, ammonia poses significant environmental and health risks, emphasizing the need for efficient monitoring. Although traditional gas sensing methods effective, they often constrained by high operating temperatures and complex electronic components, limiting their practicality. In response, transparent thin films have emerged as a promising alternative, offering real-time monitoring capabilities. However, existing transparent films often rely on external stimuli for activation, resulting in higher power consumption and degradation over time. This research investigates a transparent thin film composed of poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) incorporated with graphene nanoplatelets (GNPs) for far-field ammonia gas sensing. Synthesized through a low-temperature, full-solution approach, the film demonstrates an average transmittance of 76.18 % in visible spectrum. Notably, patterning this film into a single slot antenna exhibits a significant 60 MHz frequency shift at a far-field distance of 12 cm when exposed to 50 ppm of ammonia gas. This significant frequency shift underscores the potential of the developed transparent slot antenna for practical and unobtrusive far-field sensing, advancing transparent gas sensors applications in environmental monitoring and workplace safety.

This paper demonstrates a modular architecture of a non-contact actuation micropump setup. Rapid hot embossing prototyping was employed in micropump fabrication by using printed circuit board (PCB) as a mold material in polymer casting. Actuator-membrane gap separation was studied, with experimental investigation of three separation distances: 2.0 mm, 2.5 mm and 3.5 mm. To enhance the micropump performance, interaction surface area between plunger and membrane was modeled via finite element analysis (FEA). The micropump was evaluated against two frequency ranges, which comprised a low driving frequency range (0–5 Hz, with 0.5 Hz step increments) and a nominal frequency range (0–80 Hz, with 10 Hz per step increments). The low range frequency features a linear relationship of flow rate with the operating frequency function, while two magnitude peaks were captured in the flow rate and back pressure characteristic in the nominal frequency range. Repeatability and reliability tests conducted suggest the pump performed at a maximum flow rate of 5.78 mL/min at 65 Hz and a backpressure of 1.35 kPa at 60 Hz.

Cooperative quantum cutting mechanism in a spectral converter of Tm3+/Yb3+-codoped tellurite glass is investigated by setting up and solving the theoretical model of rate equations and power propagation equations in MATLAB. Based on the optimal rare-earth (RE) ion concentration and the thickness of the spectral converter, a 155% total power conversion efficiency and a 171% total quantum conversion efficiency have been obtained. For a single-crystalline silicon solar cell, a 20.09% energy conversion efficiency under the optimized solar irradiation compared with a 17.94% energy conversion efficiency under the normalized solar irradiation has been obtained using PC1D, and the simulated relative energy conversion efficiency for the single-crystalline silicon solar cell approaches up to 1.12. These results show that the use of a spectral converter yields better single-crystalline silicon solar-cell performance compared with the normalized solar irradiation. Our results and techniques also provide a framework for investigating and optimizing the Tm3+/Yb3+ couple and other RE-doped spectral converters, potentially enabling a single-crystalline silicon solar cell with an efficiency enhancement.

In this paper, a framework for investigating and optimizing Ce3+ -Tb3+/Yb3+ tripled-doped solar spectral downconverting layer is provided. We investigate broadband solar spectral downconversion in near-infrared (NIR) quantum cutting system of Ce3+-Tb3+/Yb3+ triple-doped YBO3 employed by modeling and solving rate and power propagation equations of Ce3+-Tb3+/Yb3+ . For the optimized Ce3+, Tb3+, and Yb3+ concentrations and the thickness of doping layer, total power conversion efficiency of 176% and quantum conversion efficiency of 187% have been theoretically obtained. The total amount of NIR photon output may be increased to meet the purpose of potentially enabling a Si solar cell with a performance improvement. The paper will be also helpful to further investigate and design much more efficient rare-earth-multidoped system of broadband solar spectral conversion for further improving performances of Si solar cells.

A novel application of near-infrared quantum splitting (NIR QS) that splits one ultraviolet-visible photon into NIR multiphotons can be developed for solar energy conversion. In this paper, we theoretically investigate the underlying mechanism of NIR QS in Ho3+ single- and Ho3+-Yb3+ dual-doped β-NaYF4 by modeling and solving rate and power propagation equation system. The highest quantum efficiency is estimated to be 257% among studied systems. The total amount of output NIR photons may be increased to meet the purpose of potentially enabling a Si-cell with a photoelectric conversion efficiency enhancement. This paper could benefit for further exploring a promising NIR QS system in the exciting field of photonic devices and materials.

In this paper, we investigated the sign-of-coupling dependence of the von Neumann Entanglement Entropy (EE) between system and environment in the ground state of networks of N coupled quantum oscillators. We find that whether the EE increases or decreases with the amplitude of coupling strengths between particles depends on the repulsive or attractive nature of the couplings, and it also depends on whether the coupling is between system-environment or particles both in the environment. In particular, the EE decreases with the amplitude of an attractive coupling between particles both in the environment. We also find that the EE varies nonmonotonically with number of particles directly interacting with the system with attractive couplings; besides, the position-momentum uncertainty of the particle in the system and the EE vary contrarily when the particle-number is small. [ABSTRACT FROM AUTHOR]