Search Results (700)

Rapid urbanization necessitates high-frequency monitoring of construction-ready bare land to timely detect and prevent illegal construction. However, the utility of optical imagery is often compromised in cloud-prone regions. While Synthetic Aperture Radar (SAR) offers all-weather capabilities, it struggles to distinguish construction-ready bare land from recently harvested agricultural land, leading to severe false alarms. To address the conflict between high-frequency monitoring and semantic identification, this study proposes the SAR-based Change Screening and Optical-Scene-Informed Identification (SCS-OI) framework. The first stage performs high-recall candidate screening based on SAR backscattering changes, while the second stage incorporates historical cloud-free optical imagery as semantic guidance, enabling refined identification without requiring synchronous optical data. Experiments in Guangzhou demonstrate that the framework achieves a False Alarm Rate of 13.31%, Recall of 90.63%, Precision of 74.81%, F1-score of 81.95%, and IoU of 69.43%. Compared with the SAR-only baseline (FR = 22.4%), the two-stage design reduces false alarms while maintaining high recall. Other deep learning baselines exhibit lower F1-scores (59–73%), highlighting the effectiveness of the overall framework. These results show that the proposed two-stage framework effectively integrates high-recall candidate screening and semantic-guided refinement, providing a robust solution for high-frequency monitoring of construction-ready bare land in cloud-prone regions of Guangzhou. Full article

In the context of the global transition from fossil fuels to renewable energy, offshore wind power has emerged as a critical resource and gained increasing attention, requiring accurate assessments of coastal wind energy potential. This study presents an integrated suitability evaluation framework for offshore wind energy around Hainan Island, utilizing multi-satellite remote-sensing observations. A fused wind product was generated by applying the optimal interpolation (OI) algorithm to scatterometer data and was subsequently used to construct a wind farm suitability index (WFSI). The results classify the coastal waters of Hainan Island into three suitability tiers, with the most favorable zones located along the west coast and near the Qiongzhou Strait, collocating with 62.5% of documented wind farm projects. Further analysis on a decadal-long comparative experiment reveals a clear linkage between local wind energy potential and the El Niño-Southern Oscillation (ENSO) cycle that causes wind resources and high-suitability areas to contract during El Niño and expand during La Niña. These findings provide a refined natural source baseline for Hainan Island, clarify regional responses to climate variability, and offer a transferable remote-sensing framework for coastal wind energy assessments in similar maritime regions. Full article

This study investigates the origin and Nb–Ta enrichment mechanisms of the Middle Triassic Nare Alkaline Rocks in Gerze, central Tibet, using petrological, geochemical, and geochronological data. U–Pb zircon dating constrains the trachyte formation to the Middle Triassic, identifying NaOI as the oldest known seamount fragment in the zone and providing a key age for the early Meso-Tethyan Ocean. Whole-rock geochemistry data show the basalts possess typical OIB signatures, derived from a depleted mantle source modified by a mantle plume. The trachyte originated via a multi-stage process: Middle Triassic basaltic magmas underplated to form a deep-seated magma chamber, underwent high-pressure fractional crystallization, and the resulting crystal mush was later reheated and partially melted by subsequent magmas to generate trachytic melt. This model is supported by Hf isotopes and mineral chemistry. The rocks formed in a mature, thick-lithosphere intra-oceanic plate setting. Niobium occurs primarily as ilmenorutile with high Nb₂O₅ content, but its low modal abundance and very fine grain size imply low beneficiation recovery and limited current economic potential. However, the NaOI formed in an intra-oceanic island setting and hosts an early-stage Nb–Ta metallogenic system linked to alkaline magma differentiation, highlighting their potential for rare-metal exploration. Full article

Defect detection in the hot rolling process is closely linked to the quality of the final product. Among these defects, slab camber during the intermediate rolling stage is one of the primary manifestations of asymmetry, which significantly impairs both the quality of the finished strip and the stability of subsequent rolling processes. Conventional image-based edge detection methods for slab camber are prone to detection deviations in complex industrial environments, mainly due to their weak noise robustness. To address the scientific challenge of low accuracy and poor robustness in feature extraction for hot-rolled intermediate slab camber detection, which is induced by environmental interference in complex industrial settings, we break through the technical bottlenecks of traditional edge detection methods and existing deep learning models in terms of channel–spatial feature collaborative optimization and anti-interference fusion of multi-scale features. We establish a dense perception network model integrated with a channel–spatial attention mechanism, realize robust feature recognition of slab edges under complex working conditions, and provide theoretical and technical support for the real-time quantitative detection of slab shape defects in the hot rolling process. The proposed model significantly improves detection accuracy and robustness through multi-scale feature enhancement and noise suppression, effectively meeting the requirements for real-time quantitative detection of slab camber in the roughing rolling stage. Field experiments verify that the method increases detection accuracy by 36.55% and achieves favorable performance on evaluation metrics, including ODS and OIS. Full article

This paper presents a low-noise analog front-end (AFE) integrated circuit (IC) circuit for capacitive micro-electromechanical system (MEMS) accelerometers that can be used for optical image stabilization (OIS) in various optical imaging systems. The AFE circuit design features a fully differential chopper stabilization technique that efficiently minimizes low-frequency 1/f noise and parasitic coupling. The AFE circuit chip is fabricated in a 0.18 $\mathsf{\mu }$m complementary metal-oxide-semiconductor (CMOS) technology and co-packaged with an x-axis capacitive MEMS accelerometer based on a silicon-on-glass (SOG) process. The SOG accelerometer has a footprint of 1000 $\mathsf{\mu }\mathrm{m}$ $\times$ 950 $\mathsf{\mu }\mathrm{m}$. The packaged system demonstrates a sensitivity of 342 mV/g and a nonlinearity of 1.1% between −1 g and +1 g, a dynamic range of 88 dB, and an equivalent noise floor of 14 $\mathsf{\mu }\mathrm{g}/\sqrt{\mathrm{H}\mathrm{z}}$. Full article

Background: Orthostatic intolerance (OI) is an important factor affecting daily functional capacity in patients with long COVID. Traditionally, most OI symptoms have been attributed to exaggerated sympathetic nervous system activation associated with postural orthostatic tachycardia syndrome (POTS). Disequilibrium, also referred to as postural instability, may contribute to the development of OI in patients with long COVID. Methods: This study evaluated 32 patients with long COVID using neurological examinations and the active 10-min standing test. Disequilibrium was assessed using the Romberg and tandem gait tests. OI was defined as the inability to complete the active 10-min standing test. Results: Seven patients (22%) were diagnosed with OI. None of them had POTS, whereas six (86%) demonstrated disequilibrium, as detected by the Romberg and/or tandem gait test. POTS was observed in eight patients (25%), none of whom had OI. Disequilibrium was observed in nine patients (28%), six of whom (67%) had OI. Multiple regression analysis revealed that disequilibrium was positively associated with OI (r = 0.64, p < 0.001), whereas POTS was inversely associated (r = −0.38, p < 0.05). After 6 weeks of oral minocycline treatment in six patients and 2 weeks of repetitive transcranial magnetic stimulation therapy following minocycline in the other one patient, symptom amelioration was reported in six patients with OI. OI concomitant with disequilibrium recovered in five of the six patients treated and tested, although one patient who experienced symptom recovery failed to undergo the repeated standing test. Conclusions: Disequilibrium, rather than POTS, was the primary determinant of OI in patients with long COVID. Full article

As a key branch of online-to-offline (O2O) retail, the online-to-home (O2H) model enables goods acquisition through instant delivery, fundamentally reorienting urban retail spatial configuration from “accessibility” to “efficiency”. Using Jincheng, the main urban area of Tianjin as a case study, this research formulated a Goods Acquisition Efficiency (GAE) index to quantify the time-based efficiency gain of O2H over the conventional OIS (offline in-store) mode. An integrated XGBoost-SHAP approach was utilized to examine the spatial variations in efficiency gains and their associated factors. The results reveal that: (1) Efficiency gains follow a concentric pattern, increasing from the core to the periphery (Inner: 0.18; Middle: 0.20; Outer: 0.26), suggesting that O2H provides more pronounced benefits in peripheral areas where retail provision remains limited; (2) The dominant factors vary across zones: environmental attributes in the Inner Urban Zone, transportation and economic factors in the Outer Urban Zone; (3) O2H and OIS exhibit a complementary rather than substitutive relationship—physical stores in inner-city areas can maintain their current configuration, while peripheral zones may benefit from enhanced O2H fulfillment or conversion to micro-fulfillment centers. The GAE index and zonal comparison framework offer methodological references for differentiated optimization of urban retail networks. Full article

The reaction of the pyridylalcohol Ph₂C(OH)CH₂-2-py-6-Me (IH) with Me₃Al in refluxing toluene led to the isolation of the dimer [AlMe₂(μ-OC(Me)Ph₂)]₂ (1), whilst at ambient temperature the complex [(I)AlMe₂]·MeCN (2·MeCN) was isolated. Complex 1 is also readily available via the interaction of diphenylethanol and Me₃Al. Similar treatment of iPr₂C(OH)CH₂-2-py-6-Me (IIH) at ambient temperature afforded [(II)AlMe₂] (3). Treatment of IH and IIH with [VO(OiPr)₃] led to oxo-bridged complexes of the type [(VO)(μ₂-O)(I/II)]₂ (I (4·0.67MeCN), II (5)). The molecular structures of 1–5 are reported. These complexes have been employed as catalysts for the ring-opening polymerization (ROP) of the cyclic esters ε-caprolactone (ε-CL) and δ-valerolactone (δ-VL). For aluminium, complex 1/BnOH produced medium- to high-molecular-weight (M_n) PCL at 20 to 110 °C in solution, though some bi-/multi-modal behaviour was observed; for melts the M_n values were toward the lower end. For complexes 2 and 3, far lower M_n values for PCL were observed at 20 °C in solution and as melts, whilst in solution at 110 °C higher M_n values were achieved, though with less control. In general, M_n values for the PCL obtained using the vanadium complexes were low (≤8560 Da for 4, ≤2920 Da for 5). In the case of PVL, 1/BnOH in solution exhibited higher M_n values at lower temperatures with good control, and when employed as a melt, the M_n was toward the higher end (30,830 Da) observed. For 2/BnOH, much lower M_n values (≤2740 Da) were recorded both in solution and as a melt, whilst for 3, high M_n values were only observed in the absence of BnOH. Low M_n values (≤2920 Da) were also observed for the vanadium complexes 4 and 5. Kinetic results (both ε-CL and δ-VL) revealed that the vanadium complexes, particularly 4, outperformed the aluminium complexes. MALDI-ToF spectra revealed the formation of linear PCL polymers with BnO/H end groups for the aluminium/BnOH complexes in solution, and cyclic polymers when employed as melts. For vanadium, cyclic PCL polymers were the major family present. In the case of PVL, linear (BnO/H end groups) and cyclic polymers were observed when employing the Al/BnOH systems, whilst cyclic polymers were observed for vanadium. Copolymerization of ε-CL and δ-VL using 4/BnOH at 110 °C over 24 h led to incomplete conversion and formation of a random-type copolymer. Full article

This study explores the dynamics of Open Innovation (OI) in manufacturing firms, with particular attention to collaboration with public research institutions. The research is performed in the Piedmont region, Northern Italy, which represents one of Italy’s leading innovation regions, with a strong manufacturing heritage and an active strategy to foster industrial transition through innovation clusters and partnerships. The research analyzes survey responses from 82 managers and decision-makers in manufacturing firms belonging to the local manufacturing ecosystem. The questionnaire investigated how company size, organizational structure for research and development (R&D), perceived importance of collaboration, innovation drivers and barriers, and trust in research institutions affect four types of innovation: product, process, marketing, and organizational. Results indicate that collaboration with other private companies is significantly associated with product innovation, while collaboration with public research institutions is associated to both product and process innovation. The level of R&D structuring in the management of innovative projects and trust in the expertise of public research organizations are also positively associated with product innovation. In addition, key drivers—such as the availability of dedicated financial resources, staff creativity, and openness to external partnerships—are significantly related to process innovation. The findings suggest that regional policymakers and industry stakeholders should promote targeted measures to strengthen OI adoption, particularly by improving the perceived competence and transparency of public research organizations. Full article

Background/Objectives: Although anti-Müllerian hormone (AMH) is a strong biomarker of ovarian reserve and oocyte pools, it is unknown whether high AMH levels can be a reliable predictor of oocyte quality, ovulation, and embryo quality. We aimed to determine whether there is any AMH threshold value that can be used to predict treatment success in women with clomiphene citrate (CC) resistance or failure in polycystic ovary syndrome (PCOS). Methods: This retrospective cohort study included 93 infertile women with PCOS who had been previously diagnosed with CC failure or CC resistance between May 2017 and June 2018. Prior to treatment, AMH concentration was measured in all women. The participants were divided into 2 groups according to their conception after ovulation induction (OI) and intrauterine insemination (IUI). At the end of a one-year period, the medical files were assessed retrospectively. Those with and without pregnancy were compared in terms of treatment protocols, infertility periods, laboratory parameters and AMH levels. Results: Clinical and biochemical characteristics of 36 pregnant women were compared with those of 57 non-pregnant women. The results showed that the pregnant group had significantly shorter infertility periods and longer ovarian stimulations than the non-pregnant group (p < 0.05). Serum AMH levels > 4.5 ng/mL can predict OI and IUI outcome in this specific patient population, with a sensitivity of 56% and a specificity of 69%. Multivariate logistic regression analysis showed that only AMH was identified as an independent predictor of pregnancy [OR = 1.151 (95% CI: 1.034–1.280), p = 0.010]. Conclusions: Serum AMH may serve as an adjunct predictor of OI and IUI outcomes in infertile women with PCOS who failed to conceive after ≥3 cycles of CC. However, its predictive value appears to be context-dependent and should be interpreted cautiously in clinical practice. Given the distinct clinical characteristics of this patient population, individualized treatment strategies and consideration of earlier alternative therapeutic approaches may be warranted to optimize reproductive outcomes. Full article

Background: The heterogeneous nature of cancer with varying degrees of fat, necrosis, fibrosis, and varying degrees of tissue repair severely impacts the success of acquiring adequate tissue samples during percutaneous image-guided biopsy. Although ultrasound or CT fluoroscopy are used to identify tumor location and thus to guide biopsy needle insertion, these technologies do not provide the necessary resolution to determine tissue composition and enable the selection of the most appropriate location for biopsy specimen extraction. As a result, biopsy must be repeated, leading to significant cost to the health care system. Methods: In this study, we introduce a combined optical imaging/artificial intelligence (OI/AI) methodology for the real-time assessment of tissue morphology at the tip of the biopsy needle, prior to the collection of a biopsy specimen. Addressing a significant clinical challenge, this approach aims to reduce the proportion of biopsy cores—currently as high as 40%—that yield low diagnostic value due to elevated adipose or low tumor content. Our methodology employs micron-scale optical coherence tomography (OCT) imaging to obtain detailed structural tissue information using a minimally invasive needle probe. The OCT images are automatically analyzed using a convolutional neural network (CNN)-driven AI software developed by our team. A U-net style architecture was used to segment regions of tumor from the OCT scans. U-Net is a specialized convolutional neural network (CNN) architecture designed for fast, precise image segmentation, which involves classifying each pixel in an image to outline objects. This streamlined approach shows promise to provide clinicians with real-time results, supporting more accurate and informed decisions regarding biopsy site selection. To evaluate this technology, we conducted a clinical study using a custom-made OCT imager and recorded OCT images from patients diagnosed with liver cancers. Expert OCT interpreters supplied annotated reference images that were used to train a custom AI algorithm. Results: OCT imaging with ~10 mm axial and 20 mm lateral resolution enabled the collection of high-quality images of the tissue. The AI analysis was performed offline. UNet achieved an AUC of ~0.877 on the validation dataset, indicating promising performance for the relatively small data set used to train the model. The AI model matched human interpretations approximately 90% of the time, highlighting its promise for making biopsy procedures both more accurate and more efficient. Conclusions: A novel OCT instrument and AI software were evaluated for assessing tissue composition at the tip of biopsy needle. The OCT instrument produced micron-scale resolution images of the tissue, enabling AI analysis and accurate real-time discrimination of tissue type. This preliminary study demonstrated the clinical potential of this technology for improving biopsy success. Full article

High-resolution short-wave infrared (SWIR) imaging requires photodetectors (PDs) with simultaneously low dark current and high responsivity. To achieve this goal, we demonstrate low-defect bulk germanium-on-insulator (bulk-GeOI) PDs designed for enhanced 1550 nm absorption and suppressed dark current via a resonant cavity and low-defect material platform. Devices were fabricated by direct bonding low-defect bulk Ge and thinning it to ~1300 nm, with an intrinsic layer thickness of only 800 nm. This design avoids epitaxial defects to lower intrinsic dark current while forming a resonant cavity for enhanced responsivity at 1550 nm. Precise doping and Al₂O₃/Si₃N₄ bilayer sidewall passivation were employed. From a design perspective, using low-defect bulk Ge minimizes the defects from epitaxial growth and reduces intrinsic dark current, while thinning the Ge layer enhances the resonant cavity effect to improve 1550 nm responsivity. Experimentally, despite the thin absorbing layer, our devices achieved nA-level dark currents (e.g., 18 nA at −1 V for 10 μm devices) alongside high responsivities. Detailed analysis indicates that this dark current is predominantly attributed to surface and sidewall defects from mesa etching, with minimal contribution from low-defect bulk material defects, validating the effectiveness of the bulk-Ge approach in suppressing intrinsic bulk leakage. Optically, the devices achieved high responsivities of 0.85 A/W (1310 nm) and 0.72 A/W (1550 nm), corresponding to external quantum efficiencies of 80.6% and 57.7%, respectively. This work establishes the bulk-GeOI platform as a promising path toward high-performance SWIR PDs, successfully decoupling high responsivity from bulk leakage and paving the way for future gains through refined surface and interface engineering. Full article

Archaeology and evolutionary anthropology are disciplines that have made important contributions to our understanding of the evolution of cities across time and space. In this paper we apply recent research in construction methods to explore a key aspect of the ecology of ancient cities, namely who built the houses and public monuments of the past and how the processes of construction were organised. Civic houses are often thought to have been built by householders; but we show that this is an unlikely explanation, using one well-documented city in north Greece, Olynthos. House construction gives us a unique insight into the ways that cities of the past were created. We present OIKoS (Olynthos Integrated Kostings System), a method that applies archaeological energetics analysis, offering a fully parametric and city-scale reconstruction of an ancient settlement using Rhinoceros 3D and Grasshopper. OIKoS enables rapid generation and evaluation of construction scenarios at city-scale. OIKoS has the potential to extend beyond classical archaeology, offering a scalable model relevant to heritage science, architectural history, and digital urban studies. Our research enables us to show that many more people were involved in the construction of the houses of a major civic centre than have been estimated as the total number of householders. House engineering offers a new way of understanding the emergence of ancient cities. Comparative evidence from a range of contemporary sites in the eastern and western Mediterranean provides further nuances for understanding the different activities that contributed to city building. Full article

Haloacetonitriles (HANs), toxic disinfection by-products, are unregulated in China, with no standardized analytical methods. This study established a simultaneous quantitative method for six typical HANs in drinking water using an optimized purge-and-trap gas chromatography–mass spectrometry (P&T-GC/MS) system. Key parameters, including sorbent trap selection, purge time, and moisture control settings, were systematically optimized. The OI No. 7 trap and a 13 min purge time were selected to maximize sensitivity while minimizing moisture interference. Under optimal conditions, all target analytes showed good linearity (R² > 0.999). The method detection limits (LODs) ranged from 0.007 to 0.202 μg/L, and the limits of quantitation (LOQs) ranged from 0.2 to 2.0 μg/L. Average spiked recoveries in tap water were 89.5–111.0%, with relative standard deviations (RSDs) below 5% (n = 7). A core optimization was omitting pH adjustment and ascorbic acid quenching to avoid non-target degradation of brominated HANs and ensure accurate in situ concentration determination. Application to 16 Kunshan tap water samples showed total HAN concentrations of 0.59–3.03 μg/L (average: 1.62 μg/L), dominated by bromochloroacetonitrile (BCAN) and dibromoacetonitrile (DBAN). Process analysis indicated significant synergistic HAN removal by sand filtration and activated carbon, while chloramination significantly increased brominated HANs via enhanced bromination. This efficient, sensitive P&T-GC/MS method is suitable for trace HAN monitoring and provides technical support for HAN control in water treatment. Full article

The Triple-angle Ionospheric PhotoMeter (Tri-IPM), an airglow and aurora monitoring payload onboard the Fengyun-3E (FY-3E) satellite, is designed for high-sensitivity observations of far-ultraviolet airglow during twilight from the ionosphere–thermosphere system. This compact, nadir-viewing instrument features three probes (A, B, and C) oriented at 0°, −30°, and 30° relative to the nadir direction, enabling multiangle detection of OI 135.6 nm and N₂ Lyman–Birge–Hopfield (LBH) band (147.5–162.5 nm) emissions. With a spatial resolution of ~30 km × 14 km and a responsivity exceeding 2 counts/s/R, the Tri-IPM achieves high-precision measurements while maintaining a red-leak suppression ratio of ~10⁹ to minimize spectral contamination. This paper presents the design principles, ground calibration, and preliminary on-orbit performance of the Tri-IPM. On-orbit tests demonstrate excellent agreement between the observed airglow radiances, their spatial distributions, and the solar zenith angle dependencies of the theoretical models. Furthermore, the results exhibit strong consistency with observations from the Global-scale Observations of the Limb and Disk (GOLD) mission, validating the instrument’s reliability. By providing high-sensitivity, high-resolution global observations of far-ultraviolet (FUV) twilight airglow, the Tri-IPM advances research on ionospheric–thermospheric dynamics and enhances space weather monitoring capabilities. Its integrated on-orbit calibration ensures long-term data accuracy, making it a valuable tool for both scientific studies and operational space environment surveillance. Full article