Search

ABSTRACT This work presents a new miniaturized frequency selective surface (FSS) design to be employed as an electromagnetic (EM) shield in the 2.45 GHz (ISM band) range, with optically transparent glass substrate. A step‐by‐step procedure on the miniaturization technique and the corresponding frequency response is presented. The proposed FSS layout consists of an optimized square loop and a central reactive element consisting of meandered lines. The metal layout is embedded between borosilicate glass as substrate on top and bottom sides, achieving a final periodicity of 0.12λ. A miniaturization of 69.05% was achieved, and the equivalent circuit model was synthesized to understand the EM behavior of the proposed FSS design, and results were compared. The shielding effectiveness of 53.25 dB was achieved with polarization insensitivity for both TE and TM modes, and the angular stability was also studied. A prototype of the proposed work was fabricated, and the frequency characteristics were studied in the anechoic chamber setup. Ellipsometer setup was used to study the optical properties of prototype, and optical transparency of 81.8% was achieved. The measured and simulated results show close agreement and confirm the usability of the proposed FSS in glass‐based electromagnetic interference (EMI) shielding applications in ISM band. [ABSTRACT FROM AUTHOR]

A novel method is proposed to achieve a low-profile miniaturized dual-band dielectric resonator antenna (DRA) for wireless communication applications. The cylindrical dielectric resonator (DR) is fed by a microstrip loop on the top surface of the substrate and a mountain shaped ground on the bottom surface of the substrate. This structure not only effectively transfers energy to the DR but also plays a pivotal role in establishing a lower resonance frequency of 1.73 GHz, achieving this with a compact structure (0.21λ0 × 0.18λ0 × 0.02λ0, and λ0 is the free-space wavelength at 1.73 GHz). HEM11δ mode of the cylindrical DR is employed to cover the upper frequency band of 2.8 GHz. Ultimately, the effectiveness of our suggested approach and the antenna’s performance are confirmed through the measurement. [ABSTRACT FROM AUTHOR]

The availability of realistic in vitro models is crucial for tissue engineering, disease modeling, and drug screening assays. However, reproducing the complex shapes and intricate structures of naturally occurring tissues or organs in the presence of functional cells remains a challenge. For example, it is still not trivial to obtain cell‐laden tubular structures on a micrometer scale present in the nephrons of the human kidney. Here, a unique hydrogel‐based shrinking approach making use of host–guest interactions to decrease the diameters of the preformed hydrogel tubules seeded with cells is proposed as a tool to overcome the abovementioned challenge. The hydrogels are composed of covalently crosslinked methacrylated hyaluronic acid and methacrylated dextran modified with either cyclodextrin or adamantane groups that can form dynamic bonds. The hydrogels are initially formed in the presence of small‐molecule competitors that block any interpolymer host–guest interactions, and the shrinking process is triggered by the release of these competitor molecules. The high shrinking efficiency with a shrinking factor up to eight times in volume and robust cytocompatibility make the host‐guest‐based shrinking approach an appealing tool to obtain hydrogel tubular in vitro models with the desired dimensions on demand. [ABSTRACT FROM AUTHOR]

The droplet microarray (DMA) platform is a powerful tool for high‐throughput biological and chemical applications, enabling miniaturization and parallelization of experimental processes. Capable of holding hundreds of nanoliter droplets, it facilitates the screening and analysis of samples, such as cells, bacteria, embryos, and spheroids. Handling thousands of small volumes in parallel presents significant challenges. In this study, we utilize the open format of the DMA for controlled, parallel high‐throughput liquid manipulations using the sandwich technique. We demonstrate high‐throughput medium replacement at nanoliter‐scale, maintaining high cell viability on DMA for up to 7 days; for HeLa‐CLL2 cells (adherent) and SU‐DHL4 cells (suspension), and up to 14 days for HEK293 spheroids. Additionally, we achieve highly parallel aliquot uptake from nanoliter droplets, enabling non‐destructive cell viability assessments. Furthermore, the presented method enables the parallel transfer of cell spheroids between different DMAs, allowing transfer and pooling of spheroids in seconds without damage. These advances significantly enhance the capabilities of the DMA platform, enabling long‐term cell culture in nanoliter droplets and parallel sampling for high‐throughput cell or spheroid manipulation. This broadens the scope of DMA's potential applications in fields such as cell‐based high‐throughput screening, formation of complex 3D cell models for drug screening, and microtissue engineering. [ABSTRACT FROM AUTHOR]

The market size of biosurfactants (BSs) has been expanding at an extremely fast pace due to their broad application scope. Therefore, the re-construction of cell factories with modified genomic and metabolic profiles for desired industrial performance has been an intriguing aspect. Typical mutagenesis approaches generate huge mutant libraries, whereas a battery of specific, robust, and cost-effective high-throughput screening (HTS) methods is requisite to screen target strains for desired phenotypes. So far, only a few specialized HTS assays have been developed for BSs that were successfully applied to obtain anticipated mutants. The most important milestones to reach, however, continue to be: specificity, sensitivity, throughput, and the potential for automation. Here, we discuss important colorimetric and fluorometric HTS approaches for possible intervention on automated HTS platforms. Moreover, we explain current bottlenecks in developing specialized HTS platforms for screening high-yielding producers and discuss possible perspectives for addressing such challenges. [ABSTRACT FROM AUTHOR]

The analysis of the 4 element MIMO configuration of a dual band CSRR loaded crescent slotted circular patch antenna is presented in this paper. The primary radiator of the proposed antenna is the logo of the author's institute. The design of primary radiator follows a fixed geometry, which includes the crescent slot, star shaped slots and a spline split. The undefined structures in the logo are the main challenge to obtain the desired resonance frequency. The CSRR etched at the ground plane of the antenna helps to attain the desired resonance at 2.15 GHz and 2.4 GHz. The 4 element MIMO configuration is proposed to serve the high data rate applications. When four similar antenna elements are placed on the single substrate, the CSRR provides high isolation too. To design the compact MIMO, the distance between the antenna elements is kept as minimum. Hence the distance between the antenna elements is maintained asλ/4 to mitigate the effects of multipath propagation as well as to minimize the interferences between the antenna elements. The complete antenna is designed on the FR4 substrate (εr = 4.4). The simulations are carried out using Ansys HFSS 2023 R2. The prototype of the designed antenna is developed and tested. The measured return loss is well below the 10 dB and the gain is 6.28 dB at 2.4 GHz resonance. The MIMO analysis of the antenna shows high isolation between the elements (<-13 dB), low envelope correlation co-efficient (0.00008) and high directive gain (> 9.995). The obtained results ensured that the proposed antenna is well suited for Wi-Fi, bluetooth and Zigbee applications. [ABSTRACT FROM AUTHOR]

Introduction: This paper proposes a novel all-dielectric design of lens antenna and its performance is optimized using genetic algorithm (GA). The optimization objective are 1-dB and steady gain that are directly optimized. The GA also optimizes the topological design of the lens. Methods: The method consists of two main components: the design of the objective function and the initial population selection. The first lens structure fed into the algorithm and the initial population match. The lens has a diameter of 150 mm and a thickness of 30 mm at its thickest point with working frequency of 6–18 GHz. The 3D printing technology is used for the antenna fabrication that reduces the implantation cost. Results: The experimental results show that the gain and peak aperture efficiency of the proposed antenna are 23.8 dBi and 51.9%, respectively, better than those of the existing designs. Discussion: It advantages are low-cost, easy to fabricate, simple design, high gain, narrow beams, low side lobes. It can be used in future ultra-wideband (UWB) applications. [ABSTRACT FROM AUTHOR]

A novel spoof surface plasmon polaritons (SSPP) structure is applied to the design of radio frequency (RF) power amplifiers (PAs) in this work. Both standard SSPP and the proposed SSPP structures are used as input and output matching networks of a multioctave PA design. An analysis and discussion of the electromagnetic characteristics of the proposed SSPP structures is presented. Further optimization of PA performance is achieved by utilizing the gradient algorithm of the Advanced Design System tool. According to the test results, the newly developed SSPP‐based PA achieves output power ranging from 40.5 to 42.6 dBm, while the power additional efficiency varies between 60% and 66.55%, with a total layout size of 59.8 mm × 14.6 mm in the frequency band of 0.8–3.2 GHz. In comparison with recent published work, the PA designed in this work expands the bandwidth while maintaining high output power and efficiency while being smaller in size. [ABSTRACT FROM AUTHOR]

On-chip spectrometers are increasingly becoming tools that might help in everyday life needs. The possibility offered by several available integration technologies and materials to be used to miniaturize spectrometers has led to a plethora of very different devices, that in principle can be compared according to their metrics. Having access to a reference database can help in selecting the best-performing on-chip spectrometers and being up to date in terms of standards and developments. In this paper, an overview of the most relevant publications available in the literature on miniaturized spectrometers is reported and a database is provided as an open-source project to which researchers can have access and participate in order to improve the share of knowledge in the interested scientific community. [ABSTRACT FROM AUTHOR]

ABSTRACT This paper starts with the proposal of an enhanced version of a planar rectangular slot antenna fed by the quasi‐TEM printed ridge gap waveguide (PRGW), attended with a numerical study of a miniaturization procedure showing the limitations of the conventional PRGW‐based antennas. Then innovative solution is introducing a new miniaturized pure TEM wide‐band slot antenna utilizing double PRGW (D‐PRGW) technology; the proposed approach is self‐packaged and shows high potential for enhancing antenna performance, particularly in terms of bandwidth, gain, and compactness. This technology is featured with low loss, high performance, and compact size; it consists of surrounding the ridge area with a double layer of electromagnetic band gap (EBG) lattice instead of one to eliminate the surface waves effectively and keep the signal completely confined inside the ridge area with strict minimum rows of EBG. Therefore, a broad impedance matching bandwidth (|S11| ≤ −10 dB) of 33.33% is obtained from 50 to 70 GHz, which covers the unlicensed NR parts (n262; amp; n263) of the V band. Furthermore, the antenna achieves a peak gain of approximately 16 at 65 GHz while the overall efficiency remains above 90% across the entire operating frequency band. The high performance along with the compact size of this novel design makes it a good candidate for 5G wireless communications applications centered around 60 GHz. [ABSTRACT FROM AUTHOR]

A novel filter design is proposed that employs harmonic rejection characteristics based on half‐mode substrate‐integrated waveguide resonance cavities and microstrip resonators. The objective is to expand the filter's blocking bandwidth and reduce the filter's size. The filter employs two half‐mode substrate‐integrated waveguide resonant cavities, which serve to effectively reduce the size of the filter. Moreover, the higher‐order modes TE201 and TE202 are unable to propagate within the resonant cavities. The suppression of the TE102 mode is achieved by setting the coupling window between the resonant cavities at the weakest field strength of this mode. Concurrently, two microstrip resonators are integrated into the coupling window, thereby enabling the realization of a fourth‐order filter response with only two resonant cavities. The filter was processed and measured, and the results were found to be in good agreement with the simulation. It is proved that the design method proposed in this paper is feasible. [ABSTRACT FROM AUTHOR]

A novel slow‐wave half‐mode substrate integrated waveguide (HMSIW) bandpass filter (BPF) is proposed based on spoof surface plasmon polaritons (SSPPs) with loading capacitive patches (LCPs). The bandpass characteristics are achieved by etching complementary SSPPs on the metal patches of the HMSIW. SSPPs exhibit a slow‐wave effect, which effectively reduces the overall size of the filter. At the same time, using proper LCPs between the HMSIW metal via and the complementary SSPPs structure, the effective dielectric constant of the HMSIW can be changed, reducing the low cutoff frequency and further facilitating the miniaturisation of size. A prototype of the proposed filter is designed, fabricated, and measured. The measured results show that the proposed filter has the in‐band insertion loss of 1 and 3 dB passband range of 6.4–9.8 GHz. [ABSTRACT FROM AUTHOR]

Uvsq-Sat NG is a French 6U CubeSat (10 × 20 × 30 cm) of the International Satellite Program in Research and Education (INSPIRE) designed primarily for observing greenhouse gases (GHG) such as CO2 and CH4, measuring the Earth's radiation budget (ERB), and monitoring solar spectral irradiance (SSI) at the top-of-atmosphere (TOA). It epitomizes an advancement in CubeSat technology, showcasing its enhanced capabilities for comprehensive Earth observation. Scheduled for launch in 2025, the satellite carries a compact and miniaturized near-infrared (NIR) spectrometer capable of performing observations in both nadir and solar directions within the wavelength range of 1100 to 2000 nm, with a spectral resolution of 7 nm and a 0.15° field of view. This study outlines the preflight calibration process of the Uvsq-Sat NG NIR spectrometer (UNIS), with a focus on the spectral response function and the absolute calibration of the instrument. The absolute scale of the UNIS spectrometer was accurately calibrated with a quartz-halogen lamp featuring a coiled-coil tungsten filament, certified by the National Institute of Standards and Technology (NIST) as a standard of spectral irradiance. Furthermore, this study details the ground-based measurements of direct SSI through atmospheric NIR windows conducted with the UNIS spectrometer. The measurements were obtained at the Pommier site (45.54°N, 0.83°W) in Charentes–Maritimes (France) on 9 May 2024. The objective of these measurements was to verify the absolute calibration of the UNIS spectrometer conducted in the laboratory and to provide an extraterrestrial solar spectrum using the Langley-plot technique. By extrapolating the data to AirMass Zero (AM0), we obtained high-precision results that show excellent agreement with SOLAR-HRS and TSIS-1 HSRS solar spectra. At 1.6 μm, the SSI was determined to be 238.59 ± 3.39 mW.m−2.nm−1 (k = 2). These results demonstrate the accuracy and reliability of the UNIS spectrometer for both SSI observations and GHG measurements, providing a solid foundation for future orbital data collection and analysis. [ABSTRACT FROM AUTHOR]

In this work, a novel Ba(CoTi)M-spinel magnetic composite with excellent microwave dielectric-magnetic properties has been developed through a hybrid ceramic process. It can be found that the spinel magnetic nanocrystals are uniformly dispersed at the Ba(CoTi)M grain boundary, while the formation of this particular micro-concrete structure has a good effect on ceramic densification and the reduction of magnetic-dielectric loss. The composite exhibits stable electromagnetic parameters in the S and C bands, as evidenced by a permittivity of about 8, a permeability value exceeding 2, and a relatively low magnitude of tanδ ε and tanδ µ on the order of 10−2. A magnetodielectric resonant antenna operating at 6.2 GHz with a −10 dB impedance bandwidth of 27.4%, and a low profile of 0.14λ 0 was designed, fabricated, and measured based on the hybrid ferrite. The hybrid ceramic scheme plays a crucial role in designing low-loss magnetic media, possessing significant application value in high-performance microwave antennas. • Ba(CoTi)M-spinel composite is prepared by a hybrid ceramic processing technique. • The dielectric-magnetic properties are effectively improved in S and C band. • The ferrite enables the miniaturization and wideband capabilities of MDRA. [ABSTRACT FROM AUTHOR]

The genus Brachycephalus includes miniaturized toadlets with two distinct morphotypes: brightly colored species with a bufoniform phenotype and smaller, cryptic species with a leptodactyliform phenotype. The diversity of leptodactyliform species is still underappreciated, and we generally lack fundamental information about their biology. Recent sampling efforts, including DNA analyses and recordings of advertisement calls, have improved our understanding of this group. In the present study, we describe a new species of Brachycephalus, one of the smallest vertebrates known. This new species is distinguished from its congeners by a combination of morphological, bioacoustic, and genetic data. Despite being among the smallest frogs globally (the second smallest amphibian species), it exhibits skeletal traits typical of larger frogs, such as the presence of cranial bones that are lost or fused in other miniature frogs, including other Brachycephalus. Our description underscores how new discoveries within the megadiverse fauna of the Atlantic Forest—a rich biodiversity hotspot—can provide insights into phenotypic variation, including vertebrate body size. By describing this new species, we also aim to revisit the hypothesis that the type series of B. hermogenesi includes two species, potentially including individuals of the species described here. [ABSTRACT FROM AUTHOR]

This article presents a multiband bandpass filter structure with an in-line topology based on substrate-integrated waveguide (SIW) technology. A multi-layer configuration is employed to achieve circuit miniaturization. By constructing the coupling matrix, the coupling relationships among all resonators are quantitatively characterized, enabling the extraction of the theoretical frequency response and guiding circuit modeling and optimization. We designed and fabricated a third-order tri-band SIW filter and a third-order quad-band SIW filter, achieving a return loss of nearly 20 dB across all passbands. The close agreement between simulated and measured results validates the proposed design model. Additionally, the high in-band isolation of over 40 dB is demonstrated between all adjacent bands, highlighting the potential applicability of this technology in multiband scenarios. [ABSTRACT FROM AUTHOR]

Featured Application: The proposed antenna is potentially suitable for Wi-MAX (3.5 GHz) and sub-6 GHz n77 (3300–3800 MHz), n78 (3300–4200 MHz), and n79 (4400–4990 MHz), in addition to C-band applications. This study introduces a novel antenna based on the binary operation of a modified circular patch in conjunction with the Koch fractal. The antenna is intended for applications in the sub-6 GHz band, partial C-band, and X-band. The low-cost antenna is fabricated on a 1.6-mm-thick FR-4 substrate. A frequency-selective surface (FSS) is used to overcome the decreased values of the gain and bandwidth due to the fractal operations. The introduced split ring resonator (SRR) and the antenna substrate dimension reduction reduce the bandwidth and antenna gain. The air gap between the FSS and the antenna not only enhances the antenna gain but also controls the frequency tuning at the design frequency. The antenna size is miniaturized to 36.67%. A monopole antenna ground loaded with an SRR results in improved closest tuning (3.44 GHz) near the design frequency. The antenna achieves a peak gain of 9.37 dBi in this band. The FSS-based antenna results in a 4.65 dBi improvement in the gain value with the FSS. The measured and simulated plots exhibit an excellent match with each other in all three frequency bands at 2.96–4.72 GHz. These bands cover Wi-MAX (3.5 GHz), sub-6 GHz n77 (3300–3800 MHz), n78 (3300–4200 MHz), and approximately n79 (4400–4990 MHz), in addition to C-band applications. [ABSTRACT FROM AUTHOR]

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

The liquid–liquid immiscible flow and mass transfer were investigated in a novel Taylor–Couette microreactor (TCMR). Due to the rotation shear and microscale effects, each phase flowed in the form of helical strips/bands, instead of dispersion droplets as in conventional equipment. Based on the movement and inclination of the bands, the helical vortex (HV), mixed helical vortex (MHV) and stationary helical vortex (SHV) were distinguished. The characteristics of the regimes were strongly influenced by rotation speed and flow rate, but the specific surface area only slightly varied. The flow regimes also influenced the two phase mass transfer. It was shown that the mass transfer coefficient kLa monotonically increased with the rotation speed in the HV regime, while it slightly decreased when the flow shifted into the MHV/SHV regime. According to the parametric studies, empirical correlations were developed for the flow regime transition and mass transfer prediction. [ABSTRACT FROM AUTHOR]

The miniaturization of antennas is crucial as it improves the integration of wireless communication system. In order to achieve miniaturization of antennas, a performance-constrained multi-objective optimization method (PCMOM) considering the size and return loss is proposed. In the PCMOM method, an optimization strategy based on a multi-port network model is introduced, enabling the formation of antennas with various structures. Furthermore, we integrate the constraint of return loss performance into the non-dominated sorting genetic algorithm II (NSGA-II), eliminating solutions that do not meet performance requirements. Three pixel antennas are designed using the PCMOM method and two of them are fabricated. Experimental results demonstrate that the proposed PCMOM method can effectively address the complex trade-off issues in antenna miniaturization design. [ABSTRACT FROM AUTHOR]

Background Dialysis modalities and their various treatment schedules result from complex compromises ('trade-offs') between medical, financial, technological, ergonomic, and ecological factors. This study targets summarizing the mutual influence of these trade-offs on (trans)portable, wearable, or even (partially) implantable haemodialysis (HD) systems, identify what systems are in development, and how they might improve quality of life (QoL) for patients with kidney failure. Methods HD as defined by international standard IEC 60601–2-16 was applied on a PUBMED database query regarding (trans)portable, wearable, and (partly) implantable HD systems. Out of 159 search results, 24 were included and scanned for specific HD devices and/or HD systems in development. Additional information about weight, size, and development status was collected by the internet and/or contacting manufacturers. International airplane hand baggage criteria formed the boundary between transportable and portable. Technology readiness levels (TRLs) were assigned by combining TRL scales from the European Union and NATO medical staff. Results The query revealed 13 devices/projects: seven transportable (six TRL9, one TRL5); two portable (one TRL6–7, one TRL4); two wearable (one TRL6, one frozen); and two partly implantable (one TRL4–5, one TRL2–3). Discussion Three main categories of technical approaches were distinguished: single-pass, dialysate regenerating, and implantable HD filter with extracorporeal dialysate regeneration (in climbing order of mobility). Conclusions Kidneys facilitate mobility by excreting strongly concentrated waste solutes with minimal water loss. Mimicking this kidney function can increase HD system mobility. Dialysate-regenerating HD systems are enablers for portability/wearability and, combined with durable implantable HD filters (once available), they may enable HD without needles or intravascular catheters. However, lack of funding severely hampers progress. [ABSTRACT FROM AUTHOR]

In the course of Digenea evolution the transitions to a passive strategy of infection of the first intermediate host occurred multiple times. In these cases, miracidia – ciliated larvae – relinquished their role as active seekers for a suitable snail host and began relying on the chance of being accidently ingested by it. The structural changes resulting from these transitions are diverse, but the majority of them are reductive. In this study we present our ultrastructural survey on the opisthorchioid Cryptocotyle lingua miracidium. The transition to passivity led to extensive reduction in almost all somatic elements of the larva: only four epithelial plates cover its body; just a single nervous cell, a single protonephridium and a single longitudinally-oriented muscle cell have been found in this miracidium. Several undifferentiated cells comprise the germinal material of the larva. The greatest part of its body is occupied by three glandular elements. The position of these glands is consistent within Opisthorchioidea and strikingly corresponds to that of some of the optically studied miracidia of Plagiorchioidea. This similarity is suspicious, because the C. lingua larva appeared to differ vastly from other ultrastructurally described passive miracidia. Here we create a basis for the future comparison of the miracidia of Opisthorchioidea and Plagiorchioidea, expecting the ultrastructural data on the latter to be published someday. [ABSTRACT FROM AUTHOR]

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

In the context of 5G networks, this paper investigates microstrip array antennas and mobile terminal MIMO array antennas. It introduces two innovative designs and, based on these, develops and fabricates a mobile terminal antenna. The first of these designs, a 4 × 4 microstrip array antenna operating in the LTE band 42 (3.4–3.6 GHz), is researched and fabricated and an innovative approach, combining embedded and coaxial feeding methods, is proposed and employed. Measurement results indicate a bandwidth of 373 MHz (3.321–3.694 GHz), achieving a relative bandwidth of 10.7%. The antenna exhibits a high gain of 12.7 dBi, with an undistorted radiation pattern, demonstrating excellent directional characteristics. The second of these designs, a "loop-slot" MIMO antenna designed for 5G mobile devices with metal frames, is investigated. By opening slots in the metal frame and integrating them into the antenna's feeding structure, the decoupling principle is analyzed from the perspective of characteristic mode theory. This design shares resonant modes between the loop and slot antennas, allowing for the overlapping placement of the two antenna units. Experimental results confirm an isolation level exceeding 21 dB, with significantly reduced dimensions. Finally, an eight-unit MIMO antenna is designed and fabricated for 5G mobile devices with metal frames. Continuous optimization of the "loop-slot" module layout and unit spacing leads to a compact and miniaturized antenna structure. Measurement results show an isolation level exceeding 17 dB, radiation efficiency ranging from 65.8% to 73.7%, and an envelope correlation coefficient (ECC) below 0.03. Finally, an analysis of specific absorption rate (SAR) demonstrates excellent MIMO performance in terms of human body radiation exposure. [ABSTRACT FROM AUTHOR]

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

Abstract A novel slow‐wave half‐mode substrate integrated waveguide (HMSIW) bandpass filter (BPF) is proposed based on spoof surface plasmon polaritons (SSPPs) with loading capacitive patches (LCPs). The bandpass characteristics are achieved by etching complementary SSPPs on the metal patches of the HMSIW. SSPPs exhibit a slow‐wave effect, which effectively reduces the overall size of the filter. At the same time, using proper LCPs between the HMSIW metal via and the complementary SSPPs structure, the effective dielectric constant of the HMSIW can be changed, reducing the low cutoff frequency and further facilitating the miniaturisation of size. A prototype of the proposed filter is designed, fabricated, and measured. The measured results show that the proposed filter has the in‐band insertion loss of 1 and 3 dB passband range of 6.4–9.8 GHz.

Abstract The miniaturization of antennas is crucial as it improves the integration of wireless communication system. In order to achieve miniaturization of antennas, a performance-constrained multi-objective optimization method (PCMOM) considering the size and return loss is proposed. In the PCMOM method, an optimization strategy based on a multi-port network model is introduced, enabling the formation of antennas with various structures. Furthermore, we integrate the constraint of return loss performance into the non-dominated sorting genetic algorithm II (NSGA-II), eliminating solutions that do not meet performance requirements. Three pixel antennas are designed using the PCMOM method and two of them are fabricated. Experimental results demonstrate that the proposed PCMOM method can effectively address the complex trade-off issues in antenna miniaturization design.

Implantable medical devices (IMDs) are revolutionizing healthcare by enabling continuous monitoring, targeted treatment, and improved quality of life for patients with chronic conditions. Among the critical components of IMDs are implantable antennas, which facilitate reliable wireless communication for various biomedical applications, including real-time health monitoring and therapeutic interventions. The design and development of these devices present significant challenges, such as stringent miniaturization requirements, specific absorption rate (SAR) regulations, biocompatibility concerns, and the need for low power consumption to extend device longevity. This paper provides a comprehensive review of implantable medical device technologies, with a particular emphasis on implantable antennas. It highlights recent breakthroughs and novel contributions that address these complex challenges, offering a detailed analysis of advancements in antenna structures, radiation properties, and performance optimization. Key innovations in enhancing miniaturization, radiation efficiency, bandwidth, and gain are thoroughly discussed, along with the integration of advanced materials and fabrication techniques to achieve high performance while ensuring patient safety. Moreover, this paper underscores the critical importance of regulatory compliance, patient safety, and biocompatibility in the development of IMDs. Meeting these stringent standards is essential to ensure that IMDs operate safely and effectively within the human body over extended periods. By providing an in-depth review of state-of-the-art solutions and identifying emerging trends, this paper serves as an invaluable resource for researchers, engineers, and medical practitioners involved in the design and deployment of implantable medical devices. It aims to foster further innovation in the field, ultimately contributing to the creation of more sophisticated, reliable, and effective implantable medical technologies that enhance patient care and treatment outcomes.

Purpose: There is currently a strong trend in developing RF coils that are high‐density, lightweight, and highly flexible. In addition to the resonator structure of the RF coil itself, the balun or cable trap circuit serves as another essential element in the functionality and sensitivity of RF coils. This study explores the development and application of reproducible highly miniaturized baluns in RF coil design. Methods: We introduce a novel approach to producing Bazooka baluns with printed coaxial capacitors, enabling the achievement of significant capacitance per unit length. Rigorous electromagnetic simulations and thorough hardware fabrication validate the efficacy of the proposed design across various magnetic field strengths, including 1.5 T, 3 T, and 7 T MRI systems. Results: Bench testing reveals that the proposed balun can achieve an acceptable common‐mode rejection ratio even when it is highly miniaturized. The use of printed capacitors allows for a notable reduction in balun length and ensures high reproducibility. Findings demonstrate that the proposed balun exhibits no RF field distortion even when placed close to the sample, making it suitable for flexible coils, wearable coils, and high‐density coils, particularly in high‐field MRI. Conclusion: The reproducibility inherent in the manufacturing process of printed coaxial capacitors allows for simple fabrication and ensures consistency in production. These advancements pave the way for the development of flexible coils, wearable coils, and high‐density coils. [ABSTRACT FROM AUTHOR]

Wire electro-chemical discharge machining (WECDM) process is a variant of electro-chemical discharge machining process and is a novel method to machine electrically non-conductive materials. In the present research investigation, an in-house developed WECDM setup with mist flow was used to generate micro channels on borosilicate glass. The electrolyte was provided in the form of mist, formed with the combination of electrolyte and compressed air. The mist flow system was used to control the machining process that improved the stability of the spark, and flushing in the machining zone resulted in a smooth surface of machined channels. Electrolyte concentration, duty factor, wire feed rate, and mist flow rate were chosen as input process parameters, and their effect on output quality characteristics such as material removal rate and width of cut was evaluated. the performance of were during. The addition of the mist flow technique in the process resulted in an improvement in surface finish, heat affected zone (HAZ) and discharge characteristics. ANOVA analyses were carried out to obtain the significant process parameters that affected the output characteristics. Scanning electron micrograph images were captured in order to analyze the surface morphology of the machined channel and revealed thermal cracks, HAZ, irregular surface and recast layer in the samples machined with low mist flow rate as compared to samples machined using high Mist flow rates. [ABSTRACT FROM AUTHOR]

Abstract This review presents an in-depth examination of implantable antennas for various biomedical purposes. The development of implantable antennas, including their designs, materials, and operating principles, are introduced at the beginning of the discussion. An overview of the many kinds of implantable antennas utilized in implantable medical devices (IMDs) are presented in this study. The article then discusses the important factors to consider when developing implantable antennas for biomedical purposes, including implant placement, frequency range, and power needs. This investigation additionally examines the challenges and limitations encountered with implantable antennas, including the limited space available within the human body, the requirement for biocompatible materials, the impact of surrounding tissue on antenna performance, tissue attenuation, and signal interference. This review also emphasizes the most recent advances in implanted antenna technology, such as wireless power transmission, multiband operation, and miniaturization. Furthermore, it offers illustrations of several biomedical uses for implantable antennas, including pacemaker, capsule endoscopy, intracranial pressure monitoring, retinal prostheses, and bone implants. This paper concludes with a discussion of the future of implantable antennas and their possible use in bioelectronic medicine and novel medical implants. Overall, this survey offers a thorough analysis of implantable antennas in biomedical applications, emphasizing their importance in the development of implantable medical technology.

Satellite communication has reached a turning point in transmitting data quickly and receiving signals clearly in faraway places. This paper presents a metamaterial-based antenna for distant and military applications that overcomes restrictions and performs unmatched. This project explores metamaterials to create a unique antenna. Expect to be astounded by its power to bend electromagnetic waves, miniaturize, and change our relationship with the universe. The feeding mechanism of this antenna is a modified co-planar waveguide. At 5.6 GHz, the proposed antenna unit cell measures 0.076λ0×0.2λ0, making it small thanks to its MTM characteristic. CP radiation is made when two orthogonally polarized modes are stimulated at the same time and two composite right- and left-handed transmission line unit cells are placed orthogonally. Reduced size, increased bandwidth, and improved Learn how this discovery opens new doors for high-resolution photography, broadband internet, and space exploration. One nanostructure that makes up a metamaterial is the Split Ring Resonator (SRR). SRR dimensions must be smaller than the resonance wavelength, making them crucial for near-infrared and optical responses. This effort examined nanoscale SRR characteristics in the infrared and visible ranges. SRRs composed of aluminum (Al) and gold (Au) were produced on silicon and silica substrates using electron beam lithography (EBL). The proposed structure consists of a microstrip-line-supplied SRR, a parasitic patch that is perpendicular to the ground plane, and two via holes connected by two split rings that feed the patch indirectly. Choosing the right material parameter for all such antennas depends on the planned structure. Fabrication and testing of the antenna matched simulations. Dimensions: 23.7 mm × 16.2 mm × 1.6 mm; substrate dielectric constant: 4.4. Experimental data are detailed and compared to analytical calculations. Simulation results show that metamaterials have negative permittivity and permeability in a certain frequency range, which can be predicted by an analytical method. Simulations indicated eight BRS, WiMAX, radar, and mobile phone resonance frequencies. Radiation is dipole-like in the omnidirectional in the H-plane and E-plane. 10 dB return loss and 3 dB axial ratio bandwidths are 38.6.7% and 8.1%, respectively.

Abstract Background There is a growing demand for fast and reliable plant biomolecular analyses. DNA extraction is the major bottleneck in plant nucleic acid-based applications especially due to the complexity of tissues in different plant species. Conventional methods for plant cell lysis and DNA extraction typically require extensive sample preparation processes and large quantities of sample and chemicals, elevated temperatures, and multiple sample transfer steps which pose challenges for high throughput applications. Results In a prior investigation, an ionic liquid (IL)-based modified vortex-assisted matrix solid phase dispersion approach was developed using the model plant, Arabidopsis thaliana (L.) Heynh. Building upon this foundational study, the present study established a simple, rapid and efficient protocol for DNA extraction from milligram fragments of plant tissue representing a diverse range of taxa from the plant Tree of Life including 13 dicots and 4 monocots. Notably, the approach was successful in extracting DNA from a century old herbarium sample. The isolated DNA was of sufficient quality and quantity for sensitive molecular analyses such as qPCR. Two plant DNA barcoding markers, the plastid rbcL and nuclear ribosomal internal transcribed spacer (nrITS) regions were selected for DNA amplification and Sanger sequencing was conducted on PCR products of a representative dicot and monocot species. Successful qPCR amplification of the extracted DNA up to 3 weeks demonstrated that the DNA extracted using this approach remains stable at room temperature for an extended time period prior to downstream analysis. Conclusions The method presented here is a rapid and simple approach enabling cell lysis and DNA extraction from 1.5 mg of plant tissue across a broad range of plant taxa. Additional purification prior to DNA amplification is not required due to the compatibility of the extraction solvents with qPCR. The method has tremendous potential for applications in plant biology that require DNA, including barcoding methods for agriculture, conservation, ecology, evolution, and forensics.

Abstract Representatives of Schizomida, known as short-tailed whip scorpions, are an understudied group within Megoperculata. They are found subterraneanly in tropical and sub-tropical regions. They lack eyes, have superior mobility, and possess a flagellum which is relevant to their mating, but in general little is known about their general biology. Fossil representatives of Schizomida from a variety of time periods are available for study. Using 23 fossil specimens (14 of which are described here for the first time) and 86 extant individuals from the literature, changes in both body size and flagella shape in Schizomida were compared over time. Measurements of prosoma length and leg length were used as a proxy for body size, and a comparative size analysis was carried out. Individuals from the Cretaceous period were found to be significantly smaller than extant individuals, contrary to our expectations. For flagellum shape, images were used to create reconstructions, which were then analysed using an elliptic Fourier analysis followed by a principal component analysis. The morphological diversity of the male flagellum shape was found to have decreased between the Cretaceous and modern fauna. We discuss potential explanations for our findings, although a greater understanding of the general biology of Schizomida is required to properly interpret our results.

This review presents an in-depth examination of implantable antennas for various biomedical purposes. The development of implantable antennas, including their designs, materials, and operating principles, are introduced at the beginning of the discussion. An overview of the many kinds of implantable antennas utilized in implantable medical devices (IMDs) are presented in this study. The article then discusses the important factors to consider when developing implantable antennas for biomedical purposes, including implant placement, frequency range, and power needs. This investigation additionally examines the challenges and limitations encountered with implantable antennas, including the limited space available within the human body, the requirement for biocompatible materials, the impact of surrounding tissue on antenna performance, tissue attenuation, and signal interference. This review also emphasizes the most recent advances in implanted antenna technology, such as wireless power transmission, multiband operation, and miniaturization. Furthermore, it offers illustrations of several biomedical uses for implantable antennas, including pacemaker, capsule endoscopy, intracranial pressure monitoring, retinal prostheses, and bone implants. This paper concludes with a discussion of the future of implantable antennas and their possible use in bioelectronic medicine and novel medical implants. Overall, this survey offers a thorough analysis of implantable antennas in biomedical applications, emphasizing their importance in the development of implantable medical technology. [ABSTRACT FROM AUTHOR]

To address the current demands for antenna miniaturization, ultra-bandwidth, and circular polarization in advanced medical devices, a novel ISM band implantable antenna for blood glucose monitoring has been developed. This antenna achieves miniaturization by incorporating slots in the radiation patch and adding symmetric short-circuit probes, resulting in a compact size of only 0.054λ0 × 0.054λ0 × 0.005λ0 (λ0 is the wavelength in free space in respect of the lowest working frequency). By combining two resonance points and utilizing a differential feed structure, the antenna achieves ultra-broadband and circular polarization. Simulations indicate a |S11| bandwidth of 1.1 GHz (1.65–2.75 GHz) and an effective axial ratio (based on 3 dB axis ratio) bandwidth of 590 MHz (1.89–2.48 GHz), able to cover both the ISM frequency band (2.45 GHz) and the mid-field frequency band (1.9 GHz). The antenna exhibits CP gains of −20.04 dBi at a frequency of 2.45 GHz, while it shows gains of −24.64 dBi at 1.9 GHz. Furthermore, a superstrate layer on the antenna's radiating surface enhances its biocompatibility and minimizes its impact on the human body. Simulation and experimental results indicate that the antenna can establish a stable wireless communication link for implantable continuous blood glucose monitoring systems. [ABSTRACT FROM AUTHOR]

This study investigates the efficacy of handheld Near-Infrared Spectroscopy (NIRS) devices for in-field estimation of forage quality using undried samples. The objective is to assess the precision and accuracy of multiple handheld NIRS instruments—NeoSpectra, TrinamiX, and AgroCares—when evaluating key forage quality metrics such as Crude Protein (CP), Neutral Detergent Fiber (aNDF), Acid Detergent Fiber (ADF), Acid Detergent Lignin (ADL), in vitro Total Digestibility (IVTD)and Neutral Detergent Fiber Digestibility (NDFD). Samples were collected from silage bunkers across 111 farms in New York State and scanned using different methods (static, moving, and turntable). The results demonstrate that dynamic scanning patterns (moving and turntable) enhance the predictive accuracy of the models compared to static scans. Fiber constituents (ADF, aNDF) and Crude Protein (CP) show higher robustness and minimal impact from water interference, maintaining similar R 2 values as dried samples. Conversely, IVTD, NDFD, and ADL are adversely affected by water content, resulting in lower R 2 values. This study underscores the importance of understanding the water effects on undried forage, as water's high absorption bands at 1400 and 1900 nm introduce significant spectral interference. Further investigation into the PLSR loading factors is necessary to mitigate these effects. The findings suggest that, while handheld NIRS devices hold promise for rapid, on-site forage quality assessment, careful consideration of scanning methodology is crucial for accurate prediction models. This research contributes valuable insights for optimizing the use of portable NIRS technology in forage analysis, enhancing feed utilization efficiency, and supporting sustainable dairy farming practices. [ABSTRACT FROM AUTHOR]

Introduction: The emergence of electromagnetic wave pollution as a new form of pollution in human society is attributed to the advancements in communication technology and the electronic information business. In addition to harming priceless electronic equipment, these electromagnetic radiation and interference issues brought on by electrical and electronic devices have a major negative influence on human productivity and wellbeing. The secret to getting rid of electromagnetic radiation interference (EMI) and improving performance is electromagnetic shielding technology. Metamaterial absorber is a type of metamaterial that absorb EMI radiation. The benefits of metamaterial absorbers include their lightweight, simple construction, and excellent absorptivity. Methods: This paper proposes a novel metamaterial absorber for EMI radiation absorption. It consists of dielectric layers, metamaterial shielding layer and transmission line. The reflection of radiation is reduced by miniaturization of metamaterials. Results and Discussion: Simulation results show that the proposed design has better performance as compared to existing methods. The operating frequency range is from 23.1 to 28.3 GHz. The values of S21 with and without shielding are -5 dB and -0.05 dB, and the shielding effectiveness is 10.10 dB and a maximum of 12.63 dB. [ABSTRACT FROM AUTHOR]

A new decoupling element technology is used to create a tiny circular patch mutiple input multiple output (MIMO) antenna measuring 20 × 25 × 1.6 mm3. A simple split‐ring resonator (SRR) metamaterial design with adjustable inner ring inductance and capacitance allows MIMO antennas to operate across several frequency bands. Tunable‐split ring resonators (T‐SRRs) are small and improve antenna element isolation. The proposed MIMO system provides isolation larger than 20 dB from 5.93 to 12.63 GHz. It is useful for radar applications since it includes the C‐band upper link (5.925–6.425 GHz) and the X‐band (8–12 GHz). With good tuning and network structure decoupling, antennas can operate in dual bands with isolation levels below −15 dB. Over 85% radiation efficiency and 72% miniaturization were achieved in the proposed MIMO antenna. The antenna has good radiation and diversity performance, including an envelope correlation coefficient < 0.1 and a diversity gain of 9.98 dB. These qualities make it suitable for advanced technology. [ABSTRACT FROM AUTHOR]

A Dualband Pass Frequency Selective Structure (DPSFSS) with miniaturized elements is proposed in this article. The miniaturized elements induce high inductance and capacitance values. The meandered line concept is used which extensively increases inductance of the dipole element. Very large capacitance is obtained between two meandered elements which have wide common area perpendicular to electric field for wave propagating in Z-direction. Two pass band poles and two zeros are obtained by perpendicular arrangement of meandered patterns on two sides of the substrate. Orthogonal arrangement of patterns ensure polarization symmetry (polarization insensitive) for Transverse Electric (TE) and Transverse Magnetic (TM) modes of exciting wave. Two pass band pole frequencies are positioned at 1.84 GHz and 4.53 GHz with low Insertion Losses (IL) of 0.67 dB and 1 dB, respectively. The lower and higher frequency bands have factional bandwidths of 41 % and 46 %, respectively. The transmission nulls occupy 2.8 GHz and 6.58 GHz frequencies. The structure is miniaturized to 0.032λ0 × 0.032λ0 dimensions with respect to lowest resonance residing at 1.83 GHz. The low IL at both pass bands is realized despite of using a lossy FR-4 material that can be improved to less than 0.5 dB at both the bands using less lossy materials such as F4BME or RO4003C. The proposed DPSFSS design is elaborated using Equivalent Circuit Model (ECM) and Surface Current Distribution (SCD). Measurements are performed on fabricated DPSFSS prototype and it is observed that the measured results coincide well with the simulated response. Angle stability of the DPSFSS is excellent and no unwanted resonances are observed at oblique angles upto 80° for dual polarizations of wave. [ABSTRACT FROM AUTHOR]

In this work, the design and implementation of a high-gain Hexagon Loop Antenna (HLA) for 5G and WLAN application is presented. Initially, a hexagon patch was designed to resonate at 3.5 GHz. A loopbased radiator was tailored to obtain miniaturization without affecting the overall performance of the proposed antenna. A CPW feed was utilized to maintain the wide bandwidth with improved return loss. FR-4 material was used as a dielectric to retain the low cost of the antenna. The return loss was kept well below -10 dB, from 3.2 GHz to 6.4 GHz. The gain of the proposed Microstrip Hexagon Loop Antenna (MHLA) is 5.3 dBi at 3.5 GHz and 8.2 dBi at 5.8 GHz, respectively. To improve the gain and directivity of the proposed antenna, a square-shaped AMC unit cell was considered, and finally, a [4×4] ground plane AMC was integrated with the antenna. The radiation pattern of the antenna is stable and low crosspolarization is maintained for the desired band. A simulation of the proposed antenna was carried out in the ANSYS HFSS tool and the experimental results were measured inside an anechoic chamber. The experimental and simulated results of the proposed antenna are in good agreement. Its simple and lowprofile structure, lower cost, and high gain ensure that the proposed high gain antenna is well suited for sub-6 GHz band and wireless application. [ABSTRACT FROM AUTHOR]

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

Simple Summary: Applications of nanoparticles as well as their use have increased over the past decades without sufficient research on their environmental impact. Focusing on Daphnia magna, a widely adopted aquatic organism employed to evaluate the adverse effects of pollutants, we investigated several aspects of the experimental design used in D. magna toxicity testing which could impact the observed effect of exposure to nanoparticles. Furthermore, we evaluated the feasibility of a miniaturized version of D. magna toxicity test as a potential candidate for nanoparticle toxicity assays. Results showed that the exposure vessel and its characteristics can affect the impact of nanoparticles and, therefore, skew the observed effects. Additionally, the miniaturized exposure showed that for physiology markers such as toxicity and feeding rate it can be a good alternative to the traditional setups, as it vastly reduces the amount of media and number of nanoparticles required as well as generated waste. The rapid progress of the modern world has resulted in new materials and products created at an accelerating pace. As such, nanoparticles have widespread applications and often find their way into the aquatic ecosystem. In the case of freshwater ecosystems, one of the commonly used bioindicators species used for pollution assessment is Daphnid magna. The Organization for Economic Co-operation and Development (OECD), and other organizations such as the European Chemicals Agency (ECHA) and Environmental Protection Agency (EPA), have set guidelines for acute toxicity testing in daphnids that are severely lacking in terms of information on the characteristics of the exposure vessel when studying the adverse effects of nanoparticles (NPs). Understanding the toxicity mechanisms of nanomaterials is imperative given the scarcity of information on their adverse effects. Furthermore, miniaturization of nanotoxicity assays can reduce the number of daphnids used, as well as the cost and nanomaterial waste, and provide results even at the individual animal level with enhanced reproducibility of testing. In this study, the impact of the exposure vessel on the observed physiological changes of daphnids was investigated for a silver nano ink. Exposures in eleven commercially available vessels; nine made of plastic and two made of glass were compared for 24 h. The effect of surface to volume ratio of the exposure vessel and the animal number or "crowding" during exposure was investigated in the context of miniaturizing biomarker assays as alternatives to traditional experimental setups in Daphnid magna. Toxicity curves showed differences depending on the vessel used, while a novel feeding rate assay and the activity of key enzymes were assessed as physiology endpoints. [ABSTRACT FROM AUTHOR]

A particular kind of substrate-integrated waveguide (SIW) resonator is studied inspired by loading new quadrangular-star-slot metasurfaces (QSSMs). It is demonstrated that the QSSMs can effectively make the resonator electrically smaller. Good agreement has been observed between the numerical and experimental results for a specific QSSMs-loaded SIW resonator. It is revealed that the practical SIW resonator has a patch size of 0.585λg × 0.585λg, which is smaller than the conventional 0.707λg × 0.707λg. The QSSMs-loaded SIW resonators are simple to fabricate using the current print circuit board technology at a low cost. [ABSTRACT FROM AUTHOR]

Butler Matrix networks are well established as beamforming networks for phased antenna arrays. The challenge we address in this work is to cover the entire (advanced 5G or 6G) FR3 band (7–24 GHz) with a single network, while retaining low losses and minimal size. The employed multilayer topology is also well established; however, the matching between the utilized hybrid couplers and the phase shifters constitutes a major challenge for such a wideband operation. This is achieved herein by employing meander lines with appropriate curvature and introducing two distinct design methods for the Butler Matrix. The first method focuses on designing individual components separately, followed by their integration into the overall Butler Matrix structure. This approach is demonstrated through the design, prototyping, measurements, and validation of an 8 × 8 Butler Matrix beamformer, which operates across the 6–16 GHz band (FR3 Low). The second method introduces a wideband-matching technique which simplifies the implementation process by designing the Butler Matrix as a single, unified structure. This technique is applied to both 4 × 4 and 8 × 8 Butler Matrices, which are implemented and simulated for the low FR3 band. Both design methods result in wideband operation and compact size and meet the desired performance criteria. [ABSTRACT FROM AUTHOR]

Representatives of Schizomida, known as short-tailed whip scorpions, are an understudied group within Megoperculata. They are found subterraneanly in tropical and sub-tropical regions. They lack eyes, have superior mobility, and possess a flagellum which is relevant to their mating, but in general little is known about their general biology. Fossil representatives of Schizomida from a variety of time periods are available for study. Using 23 fossil specimens (14 of which are described here for the first time) and 86 extant individuals from the literature, changes in both body size and flagella shape in Schizomida were compared over time. Measurements of prosoma length and leg length were used as a proxy for body size, and a comparative size analysis was carried out. Individuals from the Cretaceous period were found to be significantly smaller than extant individuals, contrary to our expectations. For flagellum shape, images were used to create reconstructions, which were then analysed using an elliptic Fourier analysis followed by a principal component analysis. The morphological diversity of the male flagellum shape was found to have decreased between the Cretaceous and modern fauna. We discuss potential explanations for our findings, although a greater understanding of the general biology of Schizomida is required to properly interpret our results. [ABSTRACT FROM AUTHOR]

To realize fast and accurate measurement of grain moisture with low cost, the miniaturized channel state information (CSI) acquisition equipment was used for grain moisture detection. Two feature selection algorithms of random forest and principal component analysis were adopted to extract the feature subcarriers of the CSI amplitude index, and the ten kinds of grain moisture were classified based on the selected feature subcarriers. Considering that the application in the mobility scene was limited by power consumption and arithmetic power, the breadth learning system with simple structure, fast operation speed and low arithmetic power requirement was selected for processing CSI data and was compared with the traditional convolutional neural network (CNN) in terms of accuracy and training time. The enhancement nodes of the broad learning system (BLS) were dynamically increased. The experimental results show that the principal component analysis (PCA) algorithm maximally eliminates the redundant information in the CSI data. Compared with the CNN, the BLS can achieve faster speed and better accuracy. Therefore, the PCA-BLS combination achieves the best classification results. Increasing the number of enhancement nodes can increase the training time, but the recognition accuracy is improved to some extent. [ABSTRACT FROM AUTHOR]

Miniaturized in vitro bone models, or 'mini-bones', are an emerging research tool for studying bone pathophysiology and regenerative mechanisms, and for designing new therapies. Owing to their small size, mini-bones reduce the amount of cells, materials, and resources required to fabricate and use the models. Cell spheroids/aggregates, and cell-containing microgels, microfibrous extracellular matrices (ECMs), microscaffolds, and bone organs-on-chips (OOCs) are leading examples of mini-bones. Micro- and biofabrication technologies, such as photolithography, two-photon polymerization (2PP) laser lithography, bioprinting, chemical micropatterning, and replica molding can create complex micro- and submillimeter architectures to be used as bone-mimetic microenvironments. By combining improved biomimicry and high-throughput research, mini bones may result in more reliable and faster in vitro analyses, which could decrease the gap between in vitro and in vivo outcomes. In bone tissue engineering (TE) and regeneration, miniaturized, (sub)millimeter-sized bone models have become a popular trend since they bring about physiological biomimicry, precise orchestration of concurrent stimuli, and compatibility with high-throughput setups and high-content imaging. They also allow efficient use of cells, reagents, materials, and energy. In this review, we describe the state of the art of miniaturized in vitro bone models, or 'mini-bones', describing these models based on their characteristics of (multi)cellularity and engineered extracellular matrix (ECM), and elaborating on miniaturization approaches and fabrication techniques. We analyze the performance of 'mini-bone' models according to their applications for studying basic bone biology or as regeneration models, disease models, and screening platforms, and provide an outlook on future trends, challenges, and opportunities. [ABSTRACT FROM AUTHOR]

A very compact three‐pole bandpass filter with wide upper stopband is proposed and implemented by gallium arsenide integrated passive device technology. By organizing inductor and capacitor in parallel with an LC series network, a dual‐frequency bandstop structure is constructed in the first step to achieve transmission zeros (TZs). Then, the lowpass capacitor network and highpass inductor network are wisely cascaded with the bandstop structure, thus to the realization of three‐pole bandpass filter with a wide upper stopband. Based on the even‐/odd‐mode analysis, theoretical equations for the in‐band resonances and out‐of‐band TZs are given. Then, one filter prototype centered at 4.4 GHz with 3‐dB fractional bandwidth of 45.5% is designed, fabricated, and measured. Both simulated and measured results indicate that the proposed filter exhibits a wide stopband rejection of 25 dB from 6.4 to 22.8 GHz as well as a very compact size about 0.026λg × 0.031λg. [ABSTRACT FROM AUTHOR]