Search Results (4,534)

Discrete energy-level dynamics provide a fundamental framework for understanding driven two-state systems. Here, we propose and experimentally demonstrate a classical microwave-photonic analog based on two active fiber loops. Reciprocal electro-optic sidebands coherently couple two independently sustained lasing modes. When the input RF power is increased from 11.7 to 18.7 dBm, the measured oscillation frequency increases from 0.55 to 1.00 MHz, consistent with the modulation-induced coupling predicted by the coupled-mode model. The experiment therefore demonstrates RF-power-controlled Rabi-like oscillation in an active dual-loop system. Because the optical fields and detected intensities are classical, the platform reproduces reduced two-state dynamics rather than quantum-state evolution. This proof-of-concept provides a basis for quantum-inspired microwave-photonic signal processing and future short-cavity implementations. Full article

Reproductive performance and follicular dynamics in captive female ball pythons (Python regius) were investigated to evaluate reproductive efficiency, assess the usefulness of ultrasonography, and examine the relationship between follicular size and ovulation timing. Reproductive parameters included follicular development, ovulation rate, ovulation-to-oviposition interval, egg quality, and hatching success. Monthly ultrasonographic examinations were performed from March to August using a 7.5 MHz linear probe, and the findings were compared with manual palpation. Overall, 58.3% of females ovulated and laid eggs. Ovulation occurred mainly between April and August, whereas egg laying took place from June to November. The median clutch size was six eggs, and incubation lasted approximately 58 days. Ultrasonography effectively monitored follicular development, showing progressive changes in echogenicity and significant increases in follicular diameter throughout the breeding season. A strong negative correlation was found between follicular size and days to ovulation (r = −0.88; p < 0.001). Follicles measuring ≥20 mm showed a median growth rate of 0.38 mm/day. Manual palpation showed lower diagnostic accuracy, with a 25% false-negative rate. This study provides baseline reproductive data that may improve captive breeding management, animal welfare, and future reproductive research, including the development of reproductive biotechnologies in this species. Full article

Background: To compare the clinical and ultrasonographic effects of pulsed therapeutic ultrasound (US) and pulsed shortwave diathermy (SWD) in patients with mild-to-moderate carpal tunnel syndrome (CTS). Methods: In this randomized controlled trial, 40 patients with electrophysiologically confirmed mild-to-moderate CTS were randomly allocated into two groups. Both groups received wrist splinting and tendon–nerve gliding exercises. The US group received 15 sessions of pulsed ultrasound therapy (3 MHz, 0.8 W/cm²), whereas the SWD group received 15 sessions of pulsed shortwave diathermy (80 Hz, 19.2 W). Outcomes were assessed at baseline, 1 month, and 3 months using ultrasonographic median nerve cross-sectional area (MNCSA) (primary outcome), Boston Carpal Tunnel Questionnaire (BCTQ), Visual Analog Scale (VAS) for pain, Douleur Neuropathique 4 (DN4), and handgrip strength. Results: Baseline demographic characteristics, including age (mean ± SD) and sex distribution, were comparable between groups (p > 0.05), although BCTQ Functional Status and Total scores differed significantly at baseline. Repeated-measures analyses demonstrated significant time effects for MNCSA and all secondary clinical outcomes, including BCTQ scores, VAS pain, DN4 scores, and grip strength (all p < 0.001; partial η² range: 0.51–0.75), indicating moderate-to-large effect sizes. Both the US and SWD groups showed sustained improvements at the 1- and 3-month follow-ups, with no significant differences between treatment modalities (all group × time interaction p > 0.05). Conclusions: In patients with mild-to-moderate CTS, both US and SWD administered alongside splinting and exercise were associated with significant clinical and ultrasonographic improvements over 3 months. No significant difference was observed between the two modalities. Both treatments may be considered adjunctive options within conservative management, although further controlled studies are needed to clarify modality-specific effects. Full article

This review traces Turkey’s mobile communication evolution from car phones to the commercial 5G phase launched on 1 April 2026. It combines a generation-based engineering matrix with an auditable framework covering spectrum, antenna/radio integration, RAN and core architecture, transport, performance objectives, trade-offs, costs, and evidence limits. Its quantitative synthesis uses 1990s ETSI standards, KPI targets, antenna parameters, regulatory comparisons, link budget illustrations, BTK 2026-Q1 indicators, and a deliberately limited single-point handset observation. At equal distance, free-space path loss at 3.5 GHz is 13.98 dB higher than at 700 MHz; for an illustrative path loss exponent of 3.5, the cell radius and coverage area ratios are about 0.40 and 0.159. The 2025 authorization comprises 60 MHz of paired 700 MHz spectrum and 340 MHz of 3.5 GHz TDD spectrum. The international comparison is limited to regulatory spectrum positioning and a common date fixed-broadband fiber proxy, not user-experienced performance or deployment maturity. BTK data demonstrate market and infrastructure scale, but nationwide province- and operator-level radio, latency, synchronization, energy, outage, and SA/NSA data remain unavailable. The evidence supports a pragmatic coverage-first low-/mid-band launch whose practical performance depends on site density, active antennas, fiber backhaul, synchronization, energy resilience, and legacy band refarming. Full article

The very fast transient overvoltage (VFTO) generated by the operation of disconnectors in gas-insulated switchgears (GIS) features a wide frequency band and a steep rising edge, posing a severe threat to the safe and stable operation of power grids. Accurate measurement of VFTO is a core prerequisite for the insulation protection design of power equipment. Aimed at solving the problem that ultra-high frequency (UHF) sensors widely installed in existing GIS are limited by—the built-in inductance and inability to fully reconstruct the VFTO waveform—this paper proposes a broadband VFTO measurement method based on modified UHF sensors. The VFTO measuring system based on UHF sensors was constructed and tested by modifying the structure of UHF sensors and a broadband pulse source capable of outputting equivalent frequencies from 1 kHz to 10 MHz. The results showed that the measuring system exhibited excellent high-frequency (100 kHz~1 MHz) response performance but poor low-frequency (~1 kHz) response. By introducing a voltage-follower impedance transformation module based on a high-speed operational amplifier, the UHF measuring system could accurately reconstruct the VFTO waveform during the opening and closing of the 750 kV GIS disconnector. This non-contact measurement scheme provided a highly promising and reliable technical path for on-site VFTO detection for in-service equipment without altering the existing structure of GIS. Full article

While the recently developed tissue clearing protocols pathoDISCO and activeDISCO significantly accelerate the clearing of large tissue specimens through active chemical dehydration using 2,2-dimethoxypropane, the final step of refractive index (RI) matching with viscous organic solvents as dibenzyl ether (DBE) remains restricted by slow passive diffusion. To overcome this bottleneck, we applied 40 kHz ultrasound using a standard, cost-effective laboratory bath to significantly enhance the diffusion kinetics of the clearing medium into large specimens. Our investigation on multi-centimeter-sized porcine muscle and human earlobe samples demonstrates that 40 kHz acoustic oscillations generated by a standard ultrasound cleaning device not only accelerate the clearing process but also yield superior and stable long-term optical transparency. We also tested 1 MHz high-frequency ultrasound but it offered no kinetic advantages and tended to induce tissue micro-fractures, an artifact we have not observed at 40 kHz at comparable energy levels. We therefore propose that standard 40 kHz ultrasound baths, ubiquitous in laboratories for cleaning purposes, represent an ideal and accessible tool for optimizing solvent-based tissue clearing. Full article

Hyperthermia is an adjunct therapeutic approach that induces stress responses in biological tissues via controlled heat and can enhance cancer therapy. However, many RF-based systems are fixed and limited in experimental flexibility. Therefore, the development of portable RF hyperthermia platforms is essential for in vitro optimization and preclinical investigations. This study developed a mobile 13.56 MHz RF hyperthermia system and evaluated its thermal performance and preliminary in vitro biological effects. A mobile prototype including an RF generator, matching unit, electrode chamber, sample holder, and touchscreen interface was built. Human cancer cell lines (A549 and MDA-MB-231) and non-cancerous HUVEC cells were exposed to RF power levels of 40 W and 50 W for 10 min to assess the biological effects of thermal exposure. Apoptotic responses were analyzed by Annexin V-FITC/PI flow cytometry. The system generated temperatures ranging from 40 to 50 °C depending on the applied RF power and experimental conditions. RF exposure increased apoptotic populations in a cell-dependent manner. MDA-MB-231 cells showed significantly increased apoptotic populations compared with their corresponding untreated controls, whereas A549 cells exhibited a temperature-dependent shift toward increased necrosis at higher power levels. HUVEC responses indicated limited selectivity under the tested conditions. Overall, the developed platform demonstrated both technical feasibility and biological activity, providing a practical tool for controlled in vitro RF hyperthermia studies. The findings support further mechanistic investigations and future preclinical studies aimed at optimizing RF-assisted therapeutic strategies. Full article

A compact 24 GHz FMCW radar board was evaluated for low-speed bicycle and small-vehicle sensing under strict memory and latency constraints. The hardware uses only 30 MHz modulation bandwidth, giving a nominal range resolution of about 5.0 m and a Doppler-bin spacing of about 2.57 m/s. Its small, incompletely calibrated antenna path also prevents any claim of high-angular-resolution imaging-radar performance. Within this constrained platform, the measured sequences reveal four coupled failure modes: static reflectors remain prominent in the range–Doppler map, useful low-Doppler responses are easily lost near the processed spectral boundary, weak plots do not always initiate a track, and short echo gaps can break otherwise continuous trajectories. To address these limitations, we combine frame-differential range–Doppler enhancement, quadrant-aware boundary-adaptive CA-CFAR, physically gated seed-growing initiation, and finite-frame retained Kalman tracking with SNR-weighted updates. In addition to natural bicycle and small-vehicle measurements, a labeled synthetic 64 by 32 range–Doppler benchmark is used to report Precision, Recall, F1-score, ROC/AUC, detection probability, and false alarms per frame for multiple CFAR variants. Public-radar tracking metrics are also reported on RadarScenes, a public RADIATE foggy sample, and nuScenes mini radar-only sequences with a bounded-approximation JPDA baseline. These public-radar results evaluate tracker-lifecycle and data-association behavior under public target-center observations; they are not presented as full validation of the board-specific RD-to-track pipeline. The evidence supports a bounded embedded-processing claim for this low-resolution board, not general applicability to high-resolution imaging radar systems. Full article

The maritime desert boundary layer over Bahrain often supports anomalous tropospheric propagation. This includes super-refraction and surface-based ducting. These conditions increase the risk of transboundary VHF interference across the Arabian Gulf. This study presents a descriptor-based, empirically anchored propagation-sensitivity framework for assessing these propagation risks under data-limited conditions. It provides a practical alternative in regions where long-term real-world propagation measurements are difficult to obtain. Representative regional refractivity profiles are synthesized from localized thermodynamic variables. Long-term observations from Cyprus are used as an empirical benchmark for severe anomalous propagation. The simulation framework combines ITU-R P.452 anomalous-propagation screening, two-dimensional ray tracing, and wide-angle split-step Fourier parabolic-equation (PE) modeling. Validation against 95.5 MHz field-strength measurements from Limassol, Cyprus, collected during anomalous-propagation interference from Middle East transmitters, shows that matched atmospheric profiles can produce path enhancements of up to 11 dB above free-space predictions. The analysis of critical Gulf links identifies severe low-altitude trapping conditions that exceed classical waveguide thresholds. The Doha–Manama and Abu Dhabi–Manama paths show the highest interference potential. The 98.4 MHz channel emerges as the main same-channel coordination concern. The proposed framework provides a physically grounded and meteorologically bounded method for spectrum coordination and interference assessment in coastal desert environments. Full article

This study investigates the acoustic response of ZnO-based SAW devices fabricated on ZnO/Si and ZnO/SiO₂/Si substrates through a combined finite element analysis and experimental approach. Two-dimensional FEA was used to analyze scattering parameters, three-dimensional FEA was used to determine eigenfrequencies and mode shapes, and ZnO thin films were deposited by RF magnetron sputtering with interdigital transducers defined by UV lithography. The ZnO/SiO₂/Si device exhibited Rayleigh and Sezawa-type mode resonances at 145 MHz (4350 m/s) and 234 MHz (7020 m/s), respectively, in close agreement with simulation, while the ZnO/Si device resonated at 166 MHz with a phase velocity of 4980 m/s. Incorporation of the Au sensing layer improved signal transmission by approximately 2 dB, consistent with modeling predictions. For biosensing evaluation, the device was functionalized with a thiolated ssDNA probe targeting the EGFR L858R point mutation, a clinically relevant lung cancer biomarker. Probe immobilization and target hybridization were confirmed by contact angle measurements and resonance frequency shifts, with the sensor demonstrating a linear detection range of 0.1 to 0.6 µM and LOD of 0.09 µM. These findings establish an integrated framework of acoustic modeling, microfabrication, and biofunctionalization for ZnO-based SAW biosensors toward label-free nucleic acid detection. Full article

Improving the performance of computer networks using seamless Wi-Fi can be achieved by implementing a number of strategies and technologies. Strategies include, first of all, the optimal location of routers and access points, the use of a multi-band network or routers supporting different bands. Routers with support for beamforming technology, which directs the Wi-Fi signal directly to connected devices, allow you to improve the signal quality and data transfer speed. Increasing the performance of Wi-Fi computer networks is also provided by the use of network monitoring and management software, which allows you to monitor its performance and respond to possible problems in the network infrastructure. This is an important task, because it determines the quality and convenience of access to network resources. First of all, it allows you to achieve a high data transfer rate, which is especially important in conditions of high traffic necessary for demanding applications. Seamless Wi-Fi technologies also promote increased mobility and flexibility of users, allowing them to connect to the network in any place with a good signal without having to use wired connections. Network management becomes more efficient with automatic switching between access points and increased fault tolerance in the face of changing traffic usage scales. Quantitative results: Implementation of the Wi-Fi roaming mechanism using the IEEE 802.11 specification; Wi-Fi performance measurements obtained for various IEEE 802.11n HT20 and IEEE 802.11a client ratios; the original test environment included 50 laptops and netbooks from various manufacturers, equipped with various operating systems and wireless network adapters; seamless Wi-Fi technologies based on IEEE 802.11k, IEEE 802.11v, and IEEE 802.11r improve communication continuity during device mobility and support real-time AI-based decision making; Wi-Fi based on local communication standards (WLAN-Wireless Local Area Network). It allows data transmission speeds from 1 Mb∙s⁻¹ to 6.75 Gb∙s⁻¹. Indoors, the Wi-Fi range is 20 m, and outdoors 100 m; WiMax (Worldwide Interoperability for Microwave Access) is a built-in set of wireless broadband standards that provide a constant data rate of 1 Gb∙s⁻¹ and 100 Mb∙s⁻¹ in a cellular network; LR-WPANs (Low-Rate Wireless Personal Area Networks) are standards that are the basis for higher communication protocols, ZigBee. They offer data rates ranging from 40 kb to 250 kb∙s⁻¹. In devices with limited resources, these standards operate at 2.4 GHz at higher transmission speeds and 868/915 MHz at lower. The novelty in the article is the implementation of the Wi-Fi roaming mechanism, presentation of Wi-Fi scenarios, discussion of module generations, indication of integrated agriculture in terms of modern digitalization technologies, and characteristics of smart farming. Full article

This paper presents a hardware–software co-design framework for real-time super-resolution (SR) of low-quality video on resource-constrained edge platforms. At its core is a compact residual network obtained by once-for-all (OFA) neural architecture search over the Residual Channel Attention Network (RCAN) design space, trained conventionally and then optimized with quantization-aware training (QAT) for deployment on an integer-only deep-learning processing unit (DPU). Loop tiling and data-flow scheduling are applied within a custom high-level synthesis (HLS) pre-processing pipeline that feeds the DPU, and a per-directive ablation isolates the contribution of each optimization to post-route resource usage and timing. Deployed on a Kria KV260 board with a $128\times 128$ network input, the INT8 network sustains $96.37$ FPS at the ×2 scale at a measured board power of $5.38$ W, corresponding to $6.32$ Mpixel/s of reconstructed output at $1.17$ Mpixel/J, within 63.2% of the device LUT budget and with timing closed at 275 MHz. Relative to the FP32 model, INT8 quantization costs $0.274$ dB of peak signal-to-noise ratio (PSNR) on Set5, $0.172$ dB on Set14, $0.116$ dB on B100, and $0.146$ dB on Urban100, a loss dominated (81–90%) by activation rather than weight quantization. On a held-out UAV subset drawn from VisDrone2019, which is the operating domain the system targets, the network reconstructs at $25.94$ dB and $0.748$ SSIM. These results show that a twenty-three-layer residual SR network can be deployed within a 5.38 W envelope on a low-cost integer-only edge FPGA, making the approach suitable for autonomous systems, robotics, and airborne surveillance. Full article

Main memory carries data outside the processor’s trust boundary, so commodity systems-on-chip (SoCs) increasingly encrypt it; yet, in-line memory encryption engine itself becomes a differential power analysis (DPA) target whose key, if recovered, unlocks all of dynamic random-access memory (DRAM). We present PACE, a page-adaptive, cache-anchored memory encryption engine for RISC-V that makes nth-order DPA resistance practical and keeps cryptographic latency off the cache eviction critical path. PACE inserts a TileLink adapter between the last-level cache and the memory port and applies, per physical page, one of four policies (plaintext/confidentiality/confidentiality+integrity/+masking-order-d) selected from RISC-V page table bits through a memory-mapped control plane. Confidentiality uses counter mode whose per-line keystream is precomputed during cache residency; integrity is tree-free at the embedded operating point via on-chip counters and tags, with a live split counter block-MAC Bonsai Merkle tree for scale-out. DPA resistance is layered: ISAP-style fresh re-keying caps the data complexity per key at $q\approx 1$, and domain-oriented masking (DOM, d + 1 shares) protects the sole key processing block to order d. We implement PACE in Chisel on a Rocket SoC (Chipyard) and evaluate it with open-source tooling. A deterministic TileLink-level harness proves ciphertext-in-memory and detects tamper/replay/splice, and the live Tier-B engine (DRAM counters and per-line message authentication codes (MACs) plus an on-chip-rooted block-MAC tree) is validated from end to end on full Rocket and BOOM SoCs and on the FPGA; the masked Ascon-p S-box is proven order-d secure (d = 1, 2) under a glitch- and transition-aware model by three independent formal tools (COCO, PROLEAD, and SILVER, the last also deciding the full composability lattice and confirming exact glitch-robust order-2 probing security), with COCO extending the exact verdict to the highest synthesized order d = 3 (secure at probing orders 1–3); a simulated trace correlation power analysis (CPA) recovers the full key from an unprotected core and is defeated by masking, with a mutual information analysis confirming the $N\propto {\sigma }^{2(d+1)}$ trace amplification law. We further realize PACE on field-programmable gate array (FPGA) silicon: the engine plus an on-chip ring oscillator power sensor is placed, routed, timing-closed at 100 MHz, and programmed on a Xilinx XC7Z020, and we drive a fixed-vs-random Test Vector Leakage Assessment (TVLA) campaign read back entirely over a JTAG (Joint Test Action Group). A multi-core configuration and a Linux control-plane driver are likewise validated. Across synthetic access patterns and named application kernels (AES, SHA-256, matrix multiplication, pointer chasing) on both in-order Rocket and out-of-order BOOM, application-level overhead is within measurement noise of plaintext for cache resident workloads (masking, in particular, is cycle-identical to plain confidentiality), and we characterize the cost of each policy, masking order, and re-keying interval, demonstrating side-channel-hardened memory encryption on open RISC-V hardware. Full article

The use of ultra-high magnetic fields, such as 11.74 T in magnetic resonance imaging (MRI), offers great potential for achieving superior image quality and enabling advanced imaging applications. The development of new field-strength systems requires an investigation into the performance of radiofrequency transmitters and receivers. Loop coils are a popular choice for MRI scanners up to 7 T, with better performance exhibited at 3 T, whereas volume coils such as birdcage coils are preferred for 1.5 T scanners. On this basis, the field strength of 11.74 T raises the question of which resonator design will provide superior performance. Dipole antennas have been proposed for many applications involving different field strengths and target organs. One of the limitations of dipole antennas is the relationship between the resonance and the length. At 11.74 T, the dipole frequency of operation is 500 MHz, which provides a dipole antenna length of approximately 28 cm, which is acceptable for an MRI scanner. This study analyzed the transmission and reception performances of dipole arrays with different radii in terms of field intensity, uniformity, SAR, effectiveness, g-factor, and field optimization. Full article

Despite the aim of meeting the demand for long-term online monitoring of structural cracks in fields such as infrastructure, rail transit, aerospace and others, traditional detection methods fail to realize passive wireless, flexible conformal and non-contact measurement. This paper proposes a flexible wireless passive crack sensor based on resonant rings. Taking polyimide (PI) as the substrate, the sensor integrates a sensitive interdigital resonant ring structure. Variations in crack width disturb the electromagnetic field, which further leads to a resonant frequency shift to realize crack width detection. The sensing mechanism is elaborated based on microwave resonance and equivalent circuit theories. Structural optimization and crack width sensitivity analysis are carried out via electromagnetic simulation. Samples are fabricated by flexible printing technology, and a test platform is established. Experiments reveal that the sensor achieves excellent linearity within the crack width range of 0~2.5 mm, with the resonant frequency decreasing monotonically as crack width increases, and a sensitivity of 67.02 MHz/mm. It can operate stably under varying distances, installation angles and bending conditions, demonstrating outstanding flexible conformability. Featuring no power supply requirement, a chip-free design, a simple structure and strong anti-interference capability, the sensor is suitable for long-term crack monitoring of metal structures. Compared with existing studies, the proposed sensor exhibits prominent advantages in flexible adaptability, wireless passive performance and engineering practicability and can provide a novel wireless passive solution for structural health monitoring. Full article