Search Results (1,041)

Celastrol (CSL), a natural triterpenoid extracted from Tripterygium wilfordii, demonstrates a wide range of biological activities. In this study, we explored whether CSL alleviates kidney damage in spontaneously hypertensive rats (SHRs) through the modulation of the Nrf2/Ho-1 pathway, a crucial target in renal injury models. A total of 40 male SHRs, aged 6–8 weeks, were randomly allocated to four groups: the control group (CON, serving as the healthy control), the spontaneously hypertensive rat group (SHR), the SHR group treated with low-dose CSL (L-CSL + SHR, 0.5 mg/kg/d), and the SHR group treated with high-dose CSL (H-CSL + SHR, 1 mg/kg/d). All drugs were formulated using physiological saline as the solvent and administered via intraperitoneal injection. The control group received an equivalent volume of physiological saline via intraperitoneal injection, and all groups underwent continuous daily administration for 6 weeks. The results indicated that, in comparison with the control group, the serum levels of angiotensin, angiotensin-converting enzyme, and aldosterone in the SHR group were relatively high, and CSL treatment further downregulated these indices. Simultaneously, CSL downregulated pro-inflammatory factors (tumor necrosis factor-α and interleukin-1β) and upregulated interleukin-6. Regarding renal function-related indicators, CSL reduced malondialdehyde levels and enhanced the activities of antioxidant enzymes, such as superoxide dismutase, glutathione peroxidase, and catalase. Moreover, CSL inhibited the overexpression of Keap1. Significantly, the mRNA levels of Nrf2, Nqo1, and Ho-1 in the CSL-treated groups were notably higher than those in the SHR group. These findings suggest that CSL mitigates renal pathological damage in SHR by activating the Nrf2/Ho-1 pathway, offering a potential therapeutic approach for hypertension-induced renal injury. Full article

This paper proposes a continuous inertia estimation framework for transmission-level power systems with high renewable energy penetration, using a battery energy storage system (BESS) as a controllable small-signal power injection source. The proposed framework integrates BESS-based active power injection, a two-stage signal-smoothing scheme, and a rate-of-change-of-frequency (RoCoF)-based estimation mechanism to enable continuous inertia estimation without relying on major disturbance events. With noise-robust processing and moving-window analysis, the framework can reliably track inertia variations under noisy measurement conditions and diverse operating scenarios. The framework is validated on the IEEE 39-bus system under renewable energy source (RES) penetration levels of 0%, 10%, 20%, and 30%. The estimation error remains within ±3.5% across all scenarios, ranging from 1.26% at 0% RES penetration to 3.43% at 30% penetration. In addition, the estimated inertia closely follows the theoretical decrease from 3.20 s to 2.22 s as RES penetration increases. These results demonstrate the accuracy and robustness of the proposed framework for continuous inertia monitoring in low-inertia power systems with high-RES penetration. Full article

The widespread integration of wind energy conversion systems has fundamentally reshaped modern power grid architecture. However, the limited dynamic response of wind turbine (WT) converters during grid faults—particularly their inability to provide sufficient reactive current and maintain voltage stability under severe dips—necessitates a redefinition of the conventional low-voltage ride-through (LVRT) curve. This study addresses this challenge by proposing a Mutation-Adaptive Mean Variance Mapping Optimization (A-MVMO) algorithm for the control of grid-side converters (GSCs) in wind farms (WFs). To systematically assess post-fault voltage recovery, a Time-Segmented Analysis for Voltage Recovery (T-SAVR) approach is developed with a multi-objective function. The performance of the proposed A-MVMO is benchmarked against standard MVMO and conventional particle swarm optimization (PSO) under both moderate (0.7 pu) and severe (0.15 pu) voltage dips using the IEEE 39-bus system implemented in DIgSILENT/PowerFactory. The results demonstrate that A-MVMO achieves fast, oscillation-free voltage recovery with negligible overshoot (<1%) and lower current injection than PSO and MVMO, while satisfying all engineering constraints. Moreover, the co-optimization of Park-level and turbine-level controllers ensures seamless coordination, as evidenced by the close tracking between the farm-wide reactive power reference and the aggregated turbine response. The T-SAVR method proves essential for focusing optimization on controllable recovery dynamics, yielding a superior LVRT curve. Full article

Background/Objectives: It is challenging to develop efficient vaccines against intracellular pathogens such as viruses, and since viral infections are one of the main challenges for farmed salmon, a novel vaccine strategy is needed. mRNA vaccines are optimized and approved for humans, but for fish, the mRNA technology is new, and optimization is required to ensure efficient protein expression. We made an mRNA tailored to salmon and studied the effect of modified nucleosides and the length of the poly(A) tail on protein expression from in vitro-transcribed mRNA in CHSE-214 cells, using enhanced green fluorescent protein (EGFP) as a reporter. Methods: Different lengths of the poly(A) tail were tested, and various modified nucleotides were incorporated in the mRNA during in vitro transcription, including pseudouridine (Ψ), N1-methylpseudouridine (m1Ψ), N6-methyladenosine (m6A), 5-methyluridine (m5U), and 5-methylcytidine (m5C). Protein expression was observed in fluorescence microscopy and quantified using flow cytometry. Results: mRNA containing Ψ resulted in the strongest EGFP expression 1–3 days post-transfection (dpt), while EGFP expression from m5C mRNA was high throughout the experiment (<10 dpt). m5U-containing mRNA had low EGFP expression until 6 dpt, but reached the level of m5C mRNA at 10 dpt. The m5U mRNA, however, expressed EGFP at much higher intensity than all the other mRNAs at all time points. Poly(A) tails with lengths of 40, 100, and >100 were tested, and the one with >100 adenines showed the highest expression. The effects of phosphatase treatment and purification of the mRNA were also investigated. Furthermore, EGFP expression was observed in yolk-sac salmon larvae following micro-injection. Conclusions: Our study provides an important basis for the development of efficient mRNA-based vaccines in the future. Full article

Permeability is a critical parameter governing the gas flow behavior of the coalbed methane (CBM) reservoir during the exploration and exploitation of CBM, as well as the geological storage of CO₂ in the coalbeds. It is strongly associated with the multi-scale fractures developed in coal. Based on the distribution characteristics of micro-fractures, a multi-scale permeability model for coal reservoirs was established by introducing the permeability tensor, which comprehensively considers adsorption-induced coal swelling, pore pressure, effective stress, and micro-fractures. Further, the dynamic evolution law and mechanism of multi-scale permeability of coal reservoirs under different adsorption pressures were discussed. The results indicate that the increase in effective stress on the coal caused by adsorption-induced swelling essentially leads to a decrease in the equivalent multi-scale permeability of coal. Two key indicators, namely equilibrium pressure and rebound pressure, were defined to quantitatively characterize the evolution law of the equivalent multi-scale permeability during gas adsorption or desorption processes. The effective stress generated by the CO₂ adsorption-induced swelling effect in the low-rank coal is 1.47 times that in the middle-rank coal and 2.51 times that in the high-rank coal. Additionally, the effective stress generated by the CO₂ adsorption-induced swelling effect in the low-rank coal is 5.15 times that generated by N₂, while this level is 4.32 times higher than that in the middle-rank coal. Therefore, compared with the low- and middle-rank coal, the high-rank coal exhibits a smaller decrease in multi-scale permeability due to its weaker adsorption-induced swelling effect. During N₂ adsorption, the pore pressure effect dominates over the adsorption-induced swelling effect, resulting in a decrease in the effective stress on the coal with increasing gas pressure. Consequently, the equivalent multi-scale permeability of coal will increase much more significantly with an increase in injected N₂ pressure than with an increase in CO₂ pressure. By accounting for the differences between the effects of adsorption-induced swelling and pore compression on the equivalent multi-scale permeability of coal reservoir, the injectivity of CO₂ can be improved by mixing it with N₂. Full article

Accurate time synchronization is essential in distributed electrical signal monitoring, where phase coherence and event correlation depend on precise timing agreement between acquisition nodes. Conventional approaches often rely on a single synchronization source, typically internet-based Network Time Protocol (NTP) or GPS-disciplined clocks, which is impractical in isolated, offline, or cost-sensitive scenarios. This paper introduces an autonomous offline synchronization architecture for multi-node monitoring systems built on Raspberry Pi 5 (RPI5) platforms connected to a private Ethernet network. Instead of depending on one timing method, the system integrates several complementary mechanisms: battery-backed RTC persistence via the J5 interface, deterministic orchestration through systemd services, automated boot time recovery, chrony-managed NTP discipline, and Precision Time Protocol (PTP) hardware timestamping using PTP Hardware Clock (PHC). Synchronization performance is validated through continuous multi-day measurements of long-term stability, inter-node phase coherence, and short-term jitter. Controlled power-loss scenarios are also included to verify recovery behavior. The system maintains sub-microsecond alignment between nodes using only commodity hardware and no external time source. To further confirm inter-node timestamp alignment at the signal level, both hardware-based reference signal injection and software-based synchronized signal emulation are employed, providing ground-truth validation alongside scalable and reproducible evaluation. The results show that low-cost embedded hardware can support reliable, long-duration synchronization in fully offline installations. Full article

Background and Objectives: Venous thromboembolic disease (VTE), including deep vein thrombosis (DVT) and pulmonary embolism (PE), is a major cause of morbidity and mortality worldwide and imposes a substantial financial burden on health systems due to both the direct and indirect costs of acute management and long-term complications. This systematic review aimed to assess patient satisfaction with anticoagulation therapy for VTE and to highlight potential differences according to the type of anticoagulant. The review focused on factors influencing the patient experience, such as perceived efficacy, ease of use, adverse effects, and health-related quality of life. Materials and Methods: A systematic review, without quantitative meta-analysis, was conducted in accordance with PRISMA 2020 guidelines. Articles were identified through searches in major databases (PubMed, Scopus, Cochrane Library and others) using keywords including “patient satisfaction”, “anticoagulation”, “venous thromboembolic disease”, and “quality of life”. In total, 21 studies published between 2009 and 2025 met the inclusion criteria. The studies assessed patient satisfaction with different types of anticoagulation, including vitamin K antagonists (VKAs), direct oral anticoagulants (DOACs), and low-molecular-weight heparin (LMWH) injections. Results: Across the included studies, patients generally reported higher levels of treatment satisfaction with DOACs compared with VKAs, mainly due to the absence of routine laboratory monitoring and fewer dietary restrictions. However, satisfaction varied according to age, sex, and clinical status. In specific patient populations, such as those with cancer-associated thrombosis, factors including fewer drug–drug interactions and perceptions of safety with LMWH appeared to influence treatment choice and satisfaction. Adverse effects, particularly bleeding, were identified as major drivers of dissatisfaction. Several studies suggested that higher treatment satisfaction was associated with better adherence, while quality of life appeared to improve in patients treated with DOACs in comparison with VKAs. Conclusions: Patient satisfaction is a critical component of successful VTE management. Overall, DOACs appear to be associated with higher treatment satisfaction than traditional therapies such as VKAs, although further high-quality research is needed to individualise anticoagulation strategies. Systematic incorporation of patient-reported satisfaction into clinical decision-making and into international guidelines may improve adherence, enhance quality of life, and ultimately increase the effectiveness of anticoagulation therapy. Full article

Permeability evolution in hydrate-bearing porous media is a key factor controlling gas production efficiency during natural gas hydrate exploitation. In this study, laboratory experiments were conducted using sand-packed tubes filled with quartz sand and glass beads to systematically investigate the variation of liquid-phase permeability with hydrate saturation. The effects of pore structure, particle size, and initial gas injection pressure on hydrate formation and permeability reduction were analyzed. Furthermore, experimental results were compared with four commonly used permeability models, including the Kozeny model, the Dai model, the Masuda model, and the parallel capillary model. The results show that permeability decreases continuously with increasing hydrate saturation in both porous media, and the most rapid decline occurs at low saturation levels between 0 and 9%. Under the same conditions of 20–40 mesh and an initial pressure of 6.0 MPa, the pressure drop rate in the quartz-sand-packed tube reaches 1.062 kPa per minute, which is about 2.35 times higher than the 0.451 kPa per minute observed in the glass-bead-packed tube, indicating a faster hydrate formation rate and stronger permeability reduction in quartz sand. In addition, both increasing particle mesh size and raising the initial gas injection pressure significantly promote methane consumption and hydrate formation. Model comparison results demonstrate that permeability reduction is strongly dependent on pore structure. The Kozeny pore-filling model, the Dai model (M = 3), and the Masuda model (N = 8) show good agreement with the glass-bead data, whereas the Dai model (M = 8), the Masuda model (N = 15), and the pore-center form of the parallel capillary model better describe the quartz-sand system. In contrast, models based on particle-surface coating show poor agreement in both media. These findings indicate that permeability reduction is primarily controlled by pore-space occupation and flow-path restriction rather than uniform surface coverage. The results suggest that hydrate growth is more likely to occur in pore centers and critical pore-throat regions, although this conclusion is based on macroscopic model comparison and requires further validation by pore-scale observations. This study provides a quantitative basis for model selection and improves the understanding of permeability evolution in hydrate-bearing porous media. Full article

Liquid hydrogen (LH₂) fuel system architectures for aviation remain at low Technology Readiness Levels (TRLs) due to limited experimental data and the challenges of modelling cryogenic hydrogen’s behavior. This paper presents a computationally efficient framework for sensitivity analysis that integrates cryogenic thermodynamics, tank geometry, external heat ingress, engine mass flow demands, and pressurization control strategies. A set of operational scenarios was modeled to demonstrate how tank pressure and temperature evolve under various control and geometric conditions, delivering five key insights: (1) Passive tank self-pressurization leads to continuous pressure rise and subcooled liquid. (2) LH₂ withdrawal alone may not fully stop pressurization with high heat ingress. (3) Gaseous hydrogen (GH₂) injection stabilizes pressure only up to moderate heat ingress during LH₂ extraction. (4) The addition of venting enables full pressure control. (5) Tank geometry and heat flux govern transient behavior. Spherical tanks show slower pressure and temperature rise than cylindrical ones, and both geometries maintain near-constant pressure at low heat flux. These insights offer practical guidance for designing reliable and thermally stable LH₂ storage systems for future aircraft applications, paving the way towards sustainable and zero-emission aviation. Full article

Although ultrasound image segmentation has advanced significantly with deep learning, existing methods still suffer from a lack of prior knowledge guidance, partly due to the low-contrast, speckle-noise-corrupted nature from clinical ultrasound sensors. This paper proposes a novel ultrasound segmentation framework (RPFeaNet) that extracts progressive prompts from a low-to-high level prompt generation mechanism. Furthermore, the high-level prompt-guided feature interaction module (HPGFIM) fuses progressive prompt via Mamba blocks and stage-wise condition injection. The dynamic selective-frequency decoder (DSFD) combines dynamically selecting a strategy with the fusion of high-frequency details to suppress noise and refine edge details. Extensive experiments on six datasets demonstrate that RPFeaNet achieves state-of-the-art performance compared to existing methods, validating its strong generalization and robustness across diverse clinical ultrasound scenarios. Full article

The increasing penetration of rooftop photovoltaic (RTPV) systems in low-voltage (LV) distribution networks introduces challenges such as voltage rises, reverse power flow, and reduced hosting capacity, thereby necessitating effective active power regulation (APR) in module-level micro-inverters. This paper proposes a dual-layer control framework for a 250 watt-peak (Wp) three-switch rooftop PV micro-inverter, integrating quantum-behaved particle swarm optimization with reinforcement learning (QPSO-RL) for accurate maximum power point tracking (MPPT) and a linear quadratic regulator (LQR) for reserve-aware APR. The QPSO-RL algorithm improves available-power estimation under varying irradiance, temperature, and partial-shading conditions, while the LQR-based controller ensures fast, well-damped, and grid-compliant power regulation. The proposed framework was developed and validated using MATLAB/Simulink 2024 for simulation studies and LabVIEW with NI myRIO 2022 for real-time hardware implementation. Both simulation and experimental results confirm that the proposed method achieves 99.5% MPPT accuracy, convergence within 20 ms, grid-injected current total harmonic distortion (THD) below 3%, and a near-unity power factor. In addition, the reserve-based regulation strategy improves feeder compliance and reduces converter stress, thereby supporting reliable rooftop PV integration. These results demonstrate that the proposed QPSO-RL + LQR framework offers a practical and intelligent solution for high-performance, grid-supportive rooftop PV micro-inverter applications. Full article

Background/Objectives: Round spermatid injection (ROSI) is considered an experimental “last resort” option for couples with severe male factor infertility when mature spermatozoa cannot be obtained. We aimed to identify which stage of the clinical chain most strongly constrains overall success in routine practice and to describe the observed safety signal. Methods: We conducted a retrospective single-center cohort study of 221 consecutive ROSI-evaluated cycles (2021–2024). Outcomes were analyzed using a chain-of-outcome framework with explicit denominators: cycle-level feasibility (≥1 injected oocyte), two pronuclei (2PN) formation per injected oocyte, blastocyst development per 2PN, transfer per blastocyst cycle, and clinical pregnancy per transfer and per initiated cycle. Exact (Clopper–Pearson) 95% confidence intervals (CIs) were reported. Results: ROSI feasibility was observed in 5 of 221 initiated cycles (2.3%; exact 95% CI 0.7–5.2). Among the five transfer procedures performed after successful progression through upstream stages, clinical pregnancy occurred in four (80.0%; exact 95% CI 28.4–99.5). At the initiated-cycle level, overall clinical pregnancy was 4 of 221 cycles (1.8%; exact 95% CI 0.5–4.6). Conclusions: The overall effectiveness of ROSI remained low at the initiated-cycle level because very few cycles reached procedural feasibility and early attrition remained substantial. Conditional downstream outcomes may appear favorable only among the rare cycles reaching fertilization and transfer, while safety inference remains highly imprecise due to small denominators. Because only five cycles reached feasibility, all downstream conditional estimates remained highly unstable and sensitive to single-case variation. Full article

This work introduces a trimming technique based on eTrim technology to minimize both the input-referred offset voltage and its temperature drift in the operational amplifiers. The proposed low-voltage op-amp utilizes the body effect to maintain a constant bandwidth across the rail-to-rail input common-mode range under low supply voltages. During input common-mode transitions, the current in the folded cascode stage remains stable, ensuring a robust output stage. Furthermore, a specialized gain-boosting structure enhances the low-frequency gain while preventing occasional latch-up during low-voltage power-up. A pin-multiplexing scheme is employed for trimming data input, thereby eliminating the need for dedicated trimming pins and mitigating post-package parameter variations. At room temperature, a constant-current injection mechanism reduces the DC offset to microvolt levels. At high temperature, temperature-compensated current injection cancels the first-order drift component. Implemented in a low-voltage operational amplifier, post-layout simulation results demonstrate that with a 100-pF capacitive load, the amplifier achieves a gain–bandwidth product exceeding 10 MHz, a low-frequency gain greater than 140 dB, and an input-referred noise of 2.54 µVp-p for the P-channel input and 3.95 µVp-p for the N-channel input. The trimming process reduces the residual offset to the microvolt range and effectively suppresses offset drift, ensuring accurate offset compensation across the specified temperature range. Full article

Liquefied petroleum gas (LPG) is a widely available alternative fuel, easily stored in liquid form, capable of displacing diesel fuel in compression-ignition engines. Bio-LPG extends this pathway because it is a renewable drop-in form of LPG; its distinguishing advantage is not a different in-cylinder combustion chemistry, but a lower life-cycle greenhouse-gas intensity that depends on feedstock and production route. This review, therefore, combines a systematic synthesis of CI-engine LPG combustion evidence with a Bio-LPG transition perspective. A PRISMA-guided search of major databases (2000–2025) yielded 47 studies with matched diesel baseline. Evidence was categorized by LPG utilization pathway, distinguishing between fumigation, gaseous port injection, and in-cylinder LPG direct injection (gaseous or liquid), alongside engine class, pilot fuel fraction, and key operating parameters (injection timing/quantity, intake conditioning, exhaust gas recirculation (EGR), and boost). Data were normalized as percentage deviations relative to diesel and synthesized across standardized load bins (25/50/75/100%). Among studies reporting nitrogen oxides (NO_x), 20 of 37 showed net reductions, while results in 12 studies were load-dependent; particulate matter (PM), smoke, and soot indicators decreased in 17 of 27 cases. While intake-path strategies generally reduced NO_x and smoke, they often increased CO and HC emissions at low loads. The limited emerging liquid-phase direct-injection evidence shows the closest diesel-like efficiency response, although the evidence base remains limited. Overall, the engine-level findings identify the most promising LPG/Bio-LPG deployment pathways, while the specific additional climate benefit of Bio-LPG lies in its lower well-to-wheel greenhouse-gas intensity. Full article

The rapid evolution of botnet attacks poses a critical challenge facing cybersecurity, necessitating the development of intrusion detection models that are both highly accurate and computationally efficient. This paper proposes a heterogeneous radial basis function neural network structure that employs non-uniform RBF kernels to enhance discriminative capability between normal and botnet activities, leveraging flow-level packet length distribution features derived from the CTU-13 dataset, which encompasses 30 distinct botnet types, to ensure comprehensive detection across several botnet behaviors. The model was accurately evaluated across several dimensions, including training stability, robustness to noise, and overall detection accuracy and generalization performance. Experimental results demonstrate that the proposed model achieves a superior accuracy of 97.86%, with an AUC of 0.9968 and a notably low false-positive rate of 0.02. The model effectively mitigates class-imbalance bias, with an average detection rate of 94.62% even for minority botnet classes. Furthermore, inference-time evaluation showed a latency of approximately 1.0118 microseconds, confirming that the model is well-suited for high-speed networks. In addition, robustness analysis under controlled noise injection revealed a smooth degradation in performance, with accuracy remaining at 96%, highlighting the structural resilience of the proposed model and making it a robust solution for detecting modern botnet attacks. Full article