Search Results (9,000)

This study introduces two compact wideband substrate-integrated waveguide (SIW) filters fabricated using thin-film technology. The wideband bandpass response is achieved by incorporating interdigital capacitor (IDC) structures into a half-mode SIW (HMSIW) transmission line. An equivalent LC circuit model is formulated to analyze the influence of IDC parameters on the generation of transmission zeros. For the first filter (BPF 1), a third-order IDC coupling configuration is employed, resulting in a 1 dB passband spanning 11 GHz to 18 GHz, a minimum insertion loss of 0.66 dB, three transmission zeros that enhance stopband performance, and a compact core dimension of $0.49{\lambda }_g\times 0.29{\lambda }_g$. For further miniaturization, a modified HMSIW transmission line incorporating a metal-insulator-metal (MIM) capacitor at the equivalent magnetic wall is proposed. This design effectively reduces the transverse dimension of the waveguide while maintaining the original cutoff frequency. Utilizing this configuration, the second bandpass filter (BPF 2) was designed and fabricated employing double-layer ceramic thin-film technology. The resulting filter exhibits a 1 dB passband spanning 10 GHz to 18 GHz, a compact footprint measuring $0.44{\lambda }_g\times 0.23{\lambda }_g$, a minimum insertion loss of 0.58 dB, and features three transmission zeros. The fabricated and measured results of both filters show good agreement with simulations. Compared with previously reported wideband SIW filters, the proposed designs demonstrate comprehensive advantages in fractional bandwidth, insertion loss, out-of-band suppression, and circuit size, providing effective filtering solutions for high-density integration of microwave and millimeter-wave RF systems. Full article

To systematically review the research progress, methodological frameworks, and application characteristics of energy management technologies for All-Electric Ships (AES), this review provides a comprehensive and critical survey of studies published over the past two decades, following the technical trajectory of multi-energy coupling–multi-objective optimization–engineering-oriented operation. Based on a structured analysis of representative literature, the review first elucidates the overall architecture and operational characteristics of AES energy systems from a system-level perspective, highlighting their core advantages as “mobile microgrids” in terms of multi-energy coordination and dispatch flexibility. On this basis, a structured classification framework for energy management strategies is established, and the theoretical foundations, applicable scenarios, and engineering feasibility of rule-based, optimization-based, uncertainty-aware, and intelligent/data-driven approaches are comparatively reviewed and discussed. Furthermore, focusing on key research themes—including multi-energy system optimization, ship–port–microgrid coordinated operation, battery safety and lifetime-oriented management, and real-time energy management strategies—the review synthesizes the main findings and engineering validation progress reported in recent studies. The analysis indicates that, with the integration of fuel cells, renewable energy sources, and Hybrid Energy Storage Systems (HESS), energy management for AES has evolved from a single power allocation problem into a system-level optimization challenge involving multiple time scales, multiple objectives, and diverse sources of uncertainty. Optimization-based and Model Predictive Control (MPC) methods have shown promising performance in many simulation and pilot-scale studies for improving energy efficiency and emission performance, while robust optimization and data-driven approaches offer useful support for enhancing operational resilience, prediction capability, and decision quality under complex and uncertain conditions. These advances collectively contribute to the environmental, economic, and operational sustainability of maritime transport by reducing greenhouse gas emissions, extending equipment lifetime, and enabling efficient integration of renewable energy sources. At the same time, the current literature still reveals important limitations related to model fidelity, data availability, validation maturity, and the gap between methodological sophistication and practical deployment. Overall, an increasingly structured but still evolving research framework has emerged in this field. Future research should further strengthen ship–port–microgrid coordinated energy management frameworks, develop system-level optimization methods that integrate safety constraints and uncertainty, and advance intelligent Energy Management Systems (EMS) oriented toward sustainable zero-carbon shipping objectives. Full article

International timber trade has accelerated the global spread of the invasive red-haired pine bark beetle H. ligniperda, posing persistent challenges to phytosanitary inspection and border biosecurity. Rapid isothermal amplification assays are increasingly deployed in frontline quarantine settings to support timely regulatory decisions. However, their performance under the heterogeneous biological backgrounds typical of traded timber remains insufficiently evaluated, particularly with respect to the practical implications of low-level false-positive signals. We re-evaluated a previously reported isothermal assay for H. ligniperda using conditions that simulate timber transport and routine customs workflows. Fifty non-target arthropod species (predominantly insects), selected from quarantine interception records, were included to represent taxa likely to co-occur in operational contexts. Material from Lema decempunctata consistently generated weak but reproducible amplification signals across replicates. Sanger sequencing excluded contamination, confirming low-level non-target amplification in complex biological matrices. Although the signals were faint, ambiguous results in quarantine settings may trigger shipment detention, confirmatory laboratory testing, or temporary trade restrictions, thereby increasing inspection workload, delaying clearance, and generating avoidable compliance costs. These findings indicate that trade-mediated species assemblages can compromise assay performance beyond expectations derived from conventional taxonomy-based specificity testing. To reduce interpretive uncertainty and associated regulatory burden, we propose a tiered diagnostic workflow combining rapid on-site isothermal screening with specificity-oriented SYBR Green qPCR confirmation. This strategy enhances diagnostic reliability while preserving operational efficiency in applied biosecurity surveillance. Full article

Long-term cold exposure reduces livestock welfare and productivity in Inner Mongolia. This study assessed cold stress effects on 60 two-month-old female Dorper × Mongolia lambs allocated to four sheltering conditions (n = 15): indoor pens with enclosed housing (IP), outdoor pens (OP), house with playground pens (OPP), and polytunnel pens (PP). Compared with IP, OP exhibited significantly lower temperature, humidity, CO₂ concentration, NH₃ concentration, and WCI, and significantly higher wind speed and solar radiant heat (p < 0.001). Humidity, CO₂ concentration, and NH₃ concentration in PP was lower than in IP, but higher than in OP (p < 0.001); temperature, wind speed, and WCI did not differ significantly between PP and IP. ADG was significantly lower in OP and OPP than in IP (p < 0.001), whereas PP did not differ from IP. F:G was higher in OP than in IP and PP (p = 0.040). Feeding duration had significant effects on ACTH, leptin, T₃, T₄, TP, urea, TG, NEFA, LDL, and HDL concentrations. Rearing environment significantly affected GLU, ALB, LDH, and TG. Feeding duration × sheltering conditions interaction significantly influenced ACTH, TP, ALB, urea, LDH, TG, LDL, and HDL. OP induced cold stress and dysfunction, while IP and PP produced milder responses. PP raised indoor temperatures substantially, and is thus optimal for winter lamb production. Full article

Forest fires pose a considerable threat to the security of ecosystems and human society, rendering accurate assessments of fire severity critical for ecological recovery and effective fire management. The differenced Normalized Burn Ratio (dNBR) has been employed to evaluate forest fire severity; however, it presents notable uncertainties owing to variations in data sources, temporal phases, and environmental factors. To address these challenges, this study analyzed 10 forest fires occurring between 2006 and 2023 in central Yunnan Province, China. First, a rapid sampling method utilizing very high-resolution imagery was developed to assess the performance of dNBR classification under varying conditions. Second, the study identified the optimal post-fire observation window and compared classification thresholds and accuracy between Landsat and Sentinel-2 imagery in assessing fire severity. Finally, the research explored the impacts of topographic correction and pre-fire vegetation differences on classification outcomes. The findings revealed the following: (1) Imagery captured in the spring of the fire year, characterized by minimal vegetation interference, demonstrated the highest classification stability and superior capability for identifying high-severity burns. (2) Landsat outperformed Sentinel-2 in regional accuracy (0.92 vs. 0.87), and direct threshold transfer between sensors resulted in a 39% underestimation of high-severity areas, underscoring the necessity for sensor-specific calibration. (3) Topographic correction provided limited practical benefits, merely yielding a marginal improvement in accuracy (+1.44%) with the SCS+C model in steep terrain, and was generally unnecessary. (4) The influence of pre-fire vegetation was discovered to be threshold-dependent: dNBR performed reliably in forests with pre-fire NDVI > 0.5, while adjusted approaches were solely recommended for sparse or heterogeneous vegetation. Overall, this study establishes a systematic framework for optimizing dNBR-based severity assessment, enhancing its accuracy and operational utility in forest fire management. Full article

Coal gangue (CG), a bulk solid waste produced during coal mining, is rich in active components such as silicon and aluminum oxides, making it a high-quality raw material for the production of cementitious materials. Its utilization represents a significant pathway for achieving high-value applications of CG and facilitating the low-carbon transformation of the cement industry. Owing to advantages such as low carbon emissions, environmental friendliness, cost-effectiveness, and tunable performance, CG-based cementitious materials have been extensively investigated by researchers worldwide. Studies have focused on various aspects, including cementitious backfill materials, CG solid waste-based cement, geopolymers, concrete, and composite materials derived from CG. This paper systematically reviews the regional distribution, mineral composition, chemical constituents, and reactivity characteristics of CG. It further summarizes recent advances in activation techniques, performance optimization, and engineering applications of CG-based cementitious materials. Current challenges, such as insufficient activation efficiency, ambiguous hydration mechanisms, and limitations in large-scale application, are critically analyzed. Finally, future research directions and development trends are outlined to provide a theoretical foundation for further investigation and industrial implementation of CG-based cementitious materials. Full article

Prescribed burning is important for reducing wildfire risk and regulating fuel loads, but its implementation in mountainous forests is strongly influenced by the coupled effects of the wind field and topography, making it difficult to control. This study focuses on Yunnan pine (Pinus yunnanensis) forests in southwestern China. A three-dimensional Fire Dynamics Simulator (FDS) combined with measured fuel characteristics was used to simulate 21 slope (0–35°) and wind speed (0–2 m s⁻¹) combinations to quantitatively analyze the fire spread, flame structure, and gaseous emission characteristics during downslope prescribed burning. The local fire spread rate (ROS), evaluated along three lateral lines (Y = 2.5, 5.0, and 7.5 m), exhibits a non-monotonic dependence on slope over the tested range, with a minimum near 30° and a modest rebound at 35°. A downslope wind of 1 m s⁻¹ promotes near-surface heating and accelerates spread, whereas a stronger wind of 2 m s⁻¹ lifts flames away from the fuel bed and suppresses combustion. Thermal field analysis reveals that peak temperature decreases with increasing slope and that a late-stage secondary heating episode occurs at 35°. CO₂ emissions are significantly positively correlated with fuel consumption, reaching a peak of 717.5 kg under a 35° slope and no-wind conditions. CO emissions, as an indicator of combustion efficiency, reach their highest value of 2.23 kg at a 35° slope and a wind speed of 1 m s⁻¹, indicating that their trend is not entirely consistent with the ROS and temperature and that there is a certain degree of decoupling. The interaction between slope and wind speed transforms fire behavior from a cooperative to a competitive mechanism, and the topography–wind field coupling provides differentiated control over the combustion intensity and completeness. This study provides a scientific basis for the safe implementation of mountain burning programs and for regional carbon emission assessments. Full article

Desert sand concrete (DSC) cube and beam (DSCB) specimens were prepared to investigate the influence of desert sand from Ningxia, China, on the flexural behavior of concrete beams. Specimens were produced with different desert sand replacement ratios (DSRRs), and the cubic compressive strength (CCS) of DSC cubes were measured. Digital image correlation (DIC) was applied during four-point bending tests to characterize full-field strain distributions and to track crack initiation and propagation. The results indicate that CCS peaked at a DSRR of 25%. This value represented a 6% increase relative to natural sand concrete (NSC). The ultimate flexural capacity of DSCBs reached its maximum at this DSRR. This corresponded to a 2.5% increase relative to a natural sand concrete beam (NSCB). The cracks in DSCBs developed more significantly. Failure mode of DSCBs transformed from ductile to brittle at a DSRR of 50%. The current Chinese code can provide a reference for the engineering design of DSCBs, and appropriate modifications considering the DSRR are recommended for different stress stages. These findings provide a theoretical basis and technical support for the practical application of DSC. Full article

As a high-performance lightweight structural material with superior strength, Ti55531 titanium alloy has been widely adopted in critical load-bearing components such as landing gears and airframe frames in the aerospace sector to achieve significant weight reduction. However, when the tensile strength of Ti55531 exceeds 1250 MPa, the fracture toughness typically falls below 50 MPa·m^1/2. In this study, we addressed this challenge by precisely controlling the cooling rate during β annealing heat treatment. Through careful regulation of the cooling rate from the high-temperature β phase region to the aging temperature region, the Widmanstätten structure was successfully introduced into the Ti55531 titanium alloy. The experimental results demonstrate that this microstructure achieves a high tensile strength of 1252 MPa at a cooling rate of 2.5 °C/min, while simultaneously improving the elongation and fracture toughness to 9% and 84 MPa·m^1/2, respectively. Microstructural analysis reveals that the basket-weave structure plays a crucial role in maintaining high strength. Meanwhile, the Widmanstätten structure effectively increases the energy required for crack extension by resisting crack propagation and altering the crack propagation path, thus significantly enhancing fracture toughness. These findings offer a promising pathway for overcoming the traditional trade-off between strength and toughness in high-performance titanium alloys. Full article

Background: Arrhythmogenic cardiomyopathy (ACM) is an inherited disorder characterized by fibrofatty replacement of cardiomyocytes. The inflammatory episodes of ACM, known as the “hot phase”, can mimic acute myocarditis. It was seldom observed in a DES-associated ACM as a “hot-phase” presentation. Case Presentation: The proband, a 13-year-old female, initially presented with a series of clinical manifestations of fulminant myocarditis. Although recommendation-guided anti-immunotherapy had been provided, this patient still developed into an aggressive cardiomyopathy with biventricular dilation and severe systolic heart failure. Additionally, cardiac magnetic resonance demonstrated circumferential late gadolinium enhancement in left ventricular myocardium with diffuse fibrosis. Whole-exon sequencing identified a de novo missense variant, as c.335T>A (p.L112Q) of the DES gene, resulting in protein dysfunction. And a diagnosis of ACM due to a DES variant had been identified. Finally, this patient received heart transplantation, and biventricular fibrofatty infiltration was confirmed by pathological analysis. Conclusions: This case presented a de novo genetic variant that can induce severe and aggressive heart failure. This finding emphasizes the importance of comprehensive genetic analysis in patients suspected of having fulminant myocarditis, which would greatly benefit the precise clinical management and outcomes. Full article

Apple (Malus domestica Borkh.) is the most widely cultivated deciduous fruit tree with the largest industrial scale and the highest economic value in China. Fruit surface glossiness and plant stress tolerance are two core traits that determine the economic benefits and sustainable development of the apple industry. The plant epidermal cuticle is not only the core material basis for determining fruit glossiness but also the first barrier for plants to resist abiotic and biotic stresses. Glycosylphosphatidylinositol-anchored lipid transfer proteins (LTPGs) are the core functional factors mediating trans-cell wall lipid transport in plants. At present, the functions and action mechanisms of LTPG family members that simultaneously regulate fruit appearance quality and stress tolerance in apple remain largely unclear. In this study, we took the MdLTPG17 gene as the research object, clarified its biological function of stress resistance under drought stress, and dissected the molecular mechanism by which it mediates fruit glossiness formation via regulating fruit cuticle thickening. The results of this study provide important genetic resources and a theoretical basis for molecular breeding of stress resistance and targeted improvement of fruit appearance quality in apple. Full article

Brain-Derived Neurotrophic Factor (BDNF), a key member of the neurotrophin family, is critically involved in neuronal survival, synaptic plasticity, learning, and memory. While its roles in mammals have been extensively documented, the molecular regulatory mechanisms governing BDNF expression and its causal contributions to complex cognitive behaviors remain poorly understood in non-mammalian vertebrates—particularly for the domestic pigeon (Columba livia domestica), a species distinguished by its remarkable spatial navigation and homing capabilities. This review synthesizes the current evidence on BDNF in the pigeon central nervous system across five thematic domains: molecular structure and isoform diversity, transcriptional and epigenetic regulatory networks, involvement in neural development, associations with cognitive and navigational behaviors, and potential translational applications. A particular emphasis is placed on the region-specific and activity-dependent expression patterns of BDNF in brain structures such as the hippocampal formation (HF), optic tectum, and striatum, and their functional relevance to visual processing, homing behavior, and stress adaptation. To date, most findings remain correlational; therefore, establishing a mechanistic understanding necessitates the integration of advanced methodologies—including single-cell omics, CRISPR-based gene editing, and high-resolution behavioral phenotyping—to causally link BDNF dynamics, neural circuit modulation, and spatial cognition. This synthesis aims to bridge gaps in comparative neurobiology, inform molecular approaches to avian cognitive enhancement, and support evidence-based strategies for racing pigeon breeding and welfare assessment. Full article

The cascaded H-bridge static synchronous compensator (STATCOM) has been widely employed in medium- and high-voltage reactive power compensation applications due to its high modularity, fast response speed, and direct grid connection capability. However, the DC-link voltage exhibits an inherent double-frequency ripple, which poses a serious challenge to power quality. Therefore, numerous Active Power Decoupling (APD) techniques have been proposed. However, existing schemes still exhibit certain limitations: independent APD topologies are associated with higher costs, whereas single bridge-arm multiplexed APD topologies are confronted with issues such as elevated DC-side voltage and increased current stress on the multiplexed arm. Consequently, comprehensive optimization is difficult to achieve in terms of the number of power devices, decoupling accuracy, level of capacitor multiplexing, and device stress. To address the above issues, this paper proposes a DC split capacitor (DC-SC)-based dual bridge-arm multiplexed cascaded H-bridge STATCOM with active power decoupling capability, along with its corresponding control method. By constructing a fundamental-frequency common-mode voltage on the decoupling capacitor, this method effectively suppresses the double-frequency ripple in the DC-side voltage and reduces the current stress on the switching devices. The simulation and experimental results have verified the correctness and effectiveness of the proposed topological structure and control method. Full article

We present the simulation-guided design and experimental demonstration of high-speed 940 nm vertical-cavity surface-emitting lasers (VCSELs). Utilizing established device optimization principles, a simulation study was conducted focusing on the number of oxide layers and the aperture size, which predicted a maximum modulation bandwidth of over 35 GHz. To validate the simulation, a device with a 4-μm double-oxide aperture was fabricated and characterized. Additionally, a Zn-diffusion process was incorporated during fabrication to reduce p-DBR resistance and suppress higher-order transverse modes. The fabricated device achieved an experimental modulation bandwidth of 34 GHz and demonstrated successful 100 Gbit/s PAM-4 data transmission. The close agreement between the simulated and measured performance highlights the successful practical integration of these techniques for developing high-speed optical interconnects. Full article

Sub-15 nm line structures are key building blocks for advanced device prototyping, nanoscale electrodes, and lithography templates such as etch/deposition masks. Although ultrahigh-voltage (≥100 kV) electron-beam lithography (EBL) can more readily achieve extremely small critical dimensions, its tool and infrastructure requirements limit widespread adoption in many laboratories. In contrast, 30 kV field-emission SEM platforms are far more accessible; however, resolution-limit patterning at 30 kV is more sensitive to beam current, exposure dose, and development conditions, motivating the establishment of a reproducible process flow and a well-defined process window. Here, we investigate the resolution limit of isolated lines using a Zeiss Gemini 460 system operated at 30 kV and an in-house pattern generator with 950 k PMMA C2 resist. To demonstrate device-level applicability, we develop a stable lift-off process, and all critical dimensions are evaluated on metal lines after e-beam evaporation and lift-off. By screening beam current and scanning dose to build the dose-to-size relationship, we show that reducing beam current significantly improves the achievable minimum line width. Under 35 pA, using CD ≤ 15 nm as the criterion for sub-15 nm window extraction, the usable dose range is [700, 804.3] µC/cm², corresponding to a dose latitude of ~14.9%. The best performance is obtained at 700 µC/cm², yielding a transferred metal line width of 13.85 nm after lift-off. This work provides a practical resolution-limit process flow and a quantitative process window for performing sub-15 nm patterning on accessible 30 kV platforms, supported by product-level lift-off validation. Full article