Search Results (709)

The Shahejie Formation in Nanpu Sag is a crucial region for deep-layer hydrocarbon exploration in the Bohai Bay Basin. To address the impact of faults on sublacustrine fan formation and spatial distribution within the study area, this study integrated well logging, laboratory analysis, and 3D seismic data to systematically analyze sedimentary characteristics of sandbodies from the first member of the Shahejie Formation (Es₁) sublacustrine fans, clarifying their planar and cross-sectional distributions. Further research indicates that Gaoliu Fault activity during Es₁ deposition played a significant role in fan development through two mechanisms: (1) vertical displacement between hanging wall and footwall reshaped local paleogeomorphology; (2) tectonic stresses generated by fault movement affected slope stability, triggering gravitational mass transport processes that remobilized fan delta sediments into the central depression zone as sublacustrine fans through slumping and collapse mechanisms. Core observations reveal soft-sediment deformation features, including slump structures, flame structures, and shale rip-up clasts. Seismic profiles show lens-shaped geometries with thick centers thinning laterally, exhibiting lateral pinch-out terminations. Inverse fault-step architectures formed by underlying faults control sandbody distribution patterns, restricting primary deposition locations for sublacustrine fan development. The study demonstrates that sublacustrine fans in the study area are formed by gravity flow processes. A new model was established, illustrating the combined control of the Gaoliu Fault and reverse stepover faults on fan development. These findings provide valuable insights for gravity flow exploration and reservoir prediction in the Nanpu Sag, offering important implications for hydrocarbon exploration in similar lacustrine rift basins. Full article

This paper proposes a novel suspended seismic structure system called Base-suspended Pendulum Isolation (BSPI) structure. The BSPI structure can isolate seismic action and reduce structural seismic response by hanging the structure with hanger rods set at the base. The viscous dampers are installed in the isolation layer to dissipate earthquake energy and control the displacement. Firstly, the configuration of suspension isolation layer and mechanical model of the BSPI structure are described. Then, an equivalent scaled BSPI structure physical model was tested on the shaking table. The test results demonstrate that the BSPI structure has a good isolation effect under earthquakes, and the viscous dampers had an obvious control effect on the structure’s displacement and acceleration response. Finally, numerical simulation of the tests was carried out. The accuracy of the numerical models are confirmed by the good agreement between the simulation and test results. The numerical models for the BSPI structure and conventional reinforced concrete (RC) frame structure are built and analyzed using the commercial software ABAQUS. Research results indicate that the lateral stiffness of the BSPI structure is reduced greatly by installing the suspension layer, and the acceleration response of BSPI structure is significantly reduced under rare earthquakes, which is only 1/2 of that of the RC frame. The inter-story displacement of the BSPI structure is less than 1/100, which meets the seismic fortification goal and is reduced to 50% of that of the BSPI structure without damper under rare earthquakes. Full article

The Southern Lhasa Terrane, as the southernmost tectonic unit of the Eurasian continent, has long been a focal area in global geoscientific research due to its complex evolutionary history. The Yeba Formation exposed in this terrane comprises an Early–Middle Jurassic volcanic–sedimentary sequence that records multiphase tectonic deformation. This study applies structural analysis to identify three distinct phases of tectonic deformation in the Yeba Formation of the Southern Lhasa Terrane. The D₁ deformation is characterized by brittle–ductile shearing, as evidenced by the development of E-W-trending regional shear foliation (S₁). S₁ planes dip northward at angles of 27–87°, accompanied by steeply plunging stretching lineations (85–105°). Both south- and north-directed shear-rotated porphyroclasts are observed in the hanging wall. ⁴⁰Ar-³⁹Ar dating results suggest that the D₁ deformation occurred at ~79 Ma and may represent an extrusion-related structure formed under a back-arc compressional regime induced by the low-angle subduction of the Neo-Tethys Ocean plate. The D₂ deformation is marked by the folding of the pre-existing shear foliation (S₁), generating an axial planar cleavage (S₂). S₂ planes dip north or south with angles of 40–70° and fold hinges plunge westward or NWW. Based on regional tectonic evolution, it is inferred that the deformation may have resulted from sustained north–south compressional stress during the Late Cretaceous (79–70 Ma), which caused the overall upward extrusion of the southern Gangdese back-arc basin, leading to upper crustal shortening and thickening and subsequently initiating folding. The D₃ deformation is dominated by E-W-striking ductile shear zones. The regional shear foliation (S₃) exhibits a preferred orientation of 347°∠75°. Outcrop-scale ductile deformation indicators reveal a top-to-the-NW shear sense. Combined with regional tectonic evolution, the third-phase (D3) deformation is interpreted as a combined product of the transition from compression to lateral extension within the Lhasa terrane, associated with the activation of the Gangdese Central Thrust (GCT) and the uplift of the Gangdese batholith since ~25 Ma. Full article

Asynchronous-pouring construction (APC) technology employs a suspended hanging basket directly supported by corrugated steel webs (CSWs) with high shear strength, significantly enhancing construction efficiency. To further elucidate the characteristics of APC and promote its application in prestressed concrete (PC) composite box girder bridges with CSWs, this study analyzes the sustainable development of APC from two aspects, including environmental impact and economic performance. Finite element models of APC and traditional balanced cantilever construction (TBCC) were established for the case bridge with a main span of 105 m. The stress distribution and deflection of the main girder in the cantilever construction state are compared with field measurements, and the variations in stress and deflection in typical sections during construction are analyzed. Additionally, a simplified theoretical method is proposed for calculating stress and deflection in PC composite girder bridges during the cantilever construction stage using APC. Results demonstrate that APC demonstrates significant advantages in reducing economic costs and minimizing long-term environmental impacts. Furthermore, this method ensures acceptable stress and deflection throughout construction. The proposed simplified formula for CSW deflection in the maximum segment agrees well with both measured data and finite element results, providing a valuable reference for deflection calculation in APC applications. Full article

Three-dimensional (3D) spheroid models have revolutionized in vitro cancer research by offering more physiologically relevant alternatives to traditional two-dimensional (2D) cultures. A systematic search identifies English-language studies on patient-derived cancer spheroids for drug screening, using defined inclusion and exclusion criteria, with data extracted on cancer type, culture methods, spheroid characteristics, and therapeutic responses. This manuscript evaluates the methods for spheroid formation and the cellular sources used, highlighting the diverse applications and preferences in this field. The five most investigated cancer origins for spheroid seeding are breast, colon, lung, ovary, and brain cancers, reflecting their clinical importance and research focus. Among seeding methodologies, forced-floating and scaffold-based methods predominate, demonstrating reliability and versatility in spheroid generation. Other techniques, including microfluidics, bioprinting, hanging drop, and suspension culture also play significant roles, each with distinct advantages and limitations. This review underscores the increasing use of spheroid models and the need for standardization in methodologies to enhance the reproducibility and translational potential in cancer research. Full article

The integration of artificial intelligence (AI) and advanced deep learning techniques is reshaping intelligent financial forecasting and decision-support systems. This study presents a comprehensive comparative analysis of advanced deep learning models, including state-of-the-art transformer architectures and established non-transformer approaches, for long-term stock market index prediction. Utilizing historical data from major global indices (S&P 500, NASDAQ, and Hang Seng), we evaluate ten models across multiple forecasting horizons. A dual-metric evaluation framework is employed, combining traditional predictive accuracy metrics with critical financial performance indicators such as returns, volatility, maximum drawdown, and the Sharpe ratio. Statistical validation through the Mann–Whitney U test ensures robust differentiation in model performance. The results highlight that model effectiveness varies significantly with forecasting horizons and market conditions—where transformer-based models like PatchTST excel in short-term forecasts, while simpler architectures demonstrate greater stability over extended periods. This research offers actionable insights for the development of AI-driven intelligent financial forecasting systems, enhancing risk-aware investment strategies and supporting practical applications in FinTech and smart financial analytics. Full article

Purpose: Suicide is a leading cause of death among children and adolescents worldwide. This study examined the prevalence and characteristics of suicides among children and adolescents (aged ≤ 19 years) over a 13-year period in the broader area of Athens, Greece. Key aspects analyzed included victim demographics, circumstances surrounding the incidents, and methods employed. Methods: A retrospective analysis was conducted on autopsy cases performed at the Department of Forensic Medicine and Toxicology, National and Kapodistrian University of Athens, from 1 January 2011, to 31 December 2023. Results: Out of 5819 autopsies conducted between 2011 and 2023, 371 were classified as suicides. Among these, 12 cases (representing 3.2% of suicides) involved children and adolescents aged ≤ 19 years and met the study’s inclusion criteria for detailed forensic analysis. The average age of the victims was 17.7 ± 2.1 years (range: 14–19), with males representing 58.3% of cases. Hanging was the most common method of suicide (9 cases, 75.0%), followed by firearm use, falls from height, and hydrogen sulfide inhalation (one case each). Death occurred in the home in 10 cases (83.3%), with 6 specifically taking place in the bedroom. Scars indicative of prior self-harming behavior were present in two cases (16.7%), while suicide notes were found in three cases (25.0%). Toxicological analysis revealed alcohol and cannabis use in one case, cannabis alone in one case, and alcohol alone in two cases. Four victims (33.3%) had a documented psychiatric diagnosis, with two of them under antidepressant treatment at the time of death. Conclusions: This study highlights the forensic value of autopsy-based investigations in unveiling hidden patterns of adolescent suicidality and informs targeted prevention strategies. Integrating medico-legal findings into public health responses may enhance early identification and intervention in vulnerable youth populations. Full article

Background and Objectives: Suicidality in adults with Attention-Deficit/Hyperactivity Disorder (ADHD) is an emerging clinical concern, yet its mechanisms and risk factors are not fully understood. Specifically, little is known about the characteristics of suicide attempts (SAs), including the use of violent/nonviolent methods. This study aimed to investigate the prevalence and methods of SA in adults with ADHD and to identify associated sociodemographic and clinical factors. Materials and Methods: The sample included 211 adult outpatients with ADHD. Patients were grouped based on the presence/absence of a lifetime SA. Among attempters, those who used a violent method (e.g., hanging, shooting, or jumping from a height) were compared with those who used a nonviolent method (e.g., poisoning). Statistical analyses included χ² tests, Kruskal–Wallis tests, and logistic regression. Results: In total, 9.9% (n = 21; 95% CI: 4.5–10.4) of participants reported a lifetime SA, with 23.8% (n = 5; 95% CI: 4.8–41.9) using violent methods. SA was significantly associated with comorbid personality disorders (p = 0.006, OR: 6.613, 95% CI: 0.537–5.812) and a higher number of hospitalizations (p = 0.008, OR: 1.980, 95% CI: 0.296–2.675). Nonviolent methods were linked to low self-esteem (p = 0.008). No significant associations with ADHD features or other psychiatric comorbidities emerged. Conclusions: Adults with ADHD are at risk for SA, showing patterns similar to other psychiatric populations. Unlike suicidal ideation, which has been directly linked to ADHD in previous studies, the transition to an SA appeared to be associated with comorbid personality disorders. Full article

This investigation examines the corrosion behavior and mechanisms of 304 stainless steel shielded metal arc welding (SMAW) and gas metal arc welding (GMAW) joints in the simulated reservoir environment through electrochemical testing, stress-free hanging specimens and U-bend specimen immersion experiments, and microstructural characterization. The electrochemical results demonstrate that both welded joints exhibit a superior corrosion resistance in this environment, with a sensitivity of intergranular corrosion (IGC) below 1% and a corrosion rate below 0.005 mm/a. Increasing chloride concentrations elevate the passivation current densities for both the base metal and welded joints. The immersion testing revealed that after 90 days of exposure across the investigated chloride concentrations (50–300 mg/L), all welded specimens maintained surface integrity with no visible corrosion. Furthermore, U-bend specimens demonstrated no evidence of stress corrosion cracking, confirming a low stress corrosion susceptibility. Full article

Mitragyna speciosa (kratom) is a traditional medicinal plant rich in bioactive alkaloids and phenolics, known for their antioxidant and anti-aging properties. This study aimed to develop nanoparticle-based topical gels from ethanolic extracts of four kratom varieties, including Kan Daeng (KD), Hang Kang (HK), Tai Bai-yao (KY), and Kan Keaw (KG). Kratom NPs were prepared using a solvent displacement method. The resulting nanoparticles (NPs) exhibited sizes of 201.9–256.2 nm, polydispersity indices (PDI) below 0.3, and a zeta potential between −22.6 and −29.6 mV. The phytochemical analysis revealed that KG and KY extracts contained the highest total phenolic content (TPC) and total flavonoid content (TFC), which were mostly retained after NP formulation. The HPLC analysis confirmed HK as the richest source of mitragynine (9.97 ± 0.10% w/w), while NP formulations displayed slightly reduced levels. Antioxidant activities assessed by DPPH, ABTS, and FRAP assays revealed enhanced radical scavenging in nanoparticle formulations, with IC₅₀ values ranging from 151.23 to 199.87 µg/mL (DPPH) and 207.37 to 272.83 µg/mL (ABTS). All formulations exhibited a significant inhibition of collagenase (80.56 ± 1.60 to 97.23 ± 0.29%), elastase (45.46 ± 6.53 to 52.19 ± 1.20%), and hyaluronidase (83.23 ± 2.34 to 91.67 ± 3.56%), with nanoparticle forms showing superior enzyme inhibition. Notably, nanoparticle formulations exhibited superior inhibitory effects compared to crude extracts. HaCaT cytotoxicity tests confirmed high biocompatibility (IC₅₀ > 700 µg/mL), especially for KD and KG NPs. The NP-loaded gels demonstrated acceptable physicochemical stability after heating/cooling cycle testing, with pH (7.27 to 7.88), viscosity (10.719 to 12.602 Pa·s), and favorable visual and textural properties. In summary, KG and KY cultivars emerged as the most promising cosmeceutical candidates due to their superior phytochemical content, antioxidant capacity, enzyme-inhibitory activities, and formulation performance. These findings support the potential use of KG NP and KY NP-loaded gels as multifunctional cosmeceutical agents for antioxidant protection, anti-aging, and skin rejuvenation. Full article

This paper examines the firm-level carbon intensity of 83 constituent stocks in the Hang Seng Index, constructs two distinct indexes from the 20 firms with the highest and lowest carbon intensities, and analyzes the connectedness of their annualized daily volatilities with four key external factors over the past 15 years. Our findings reveal that low-carbon stocks—often represented by high-tech and financial firms—tend to exhibit higher volatility, reflecting their more dynamic business environments and greater sensitivity to changes in revenue and profitability. In contrast, high-carbon companies, such as those in the utilities and energy sectors, display more stable demand patterns and are generally less exposed to abrupt market shocks. We also find that oil price shocks result in greater volatility spillovers for low-carbon stocks. Among external influences, the U.S. stock market and Treasury yield exert the most significant spillover effects, while crude oil prices and the U.S. dollar–Chinese yuan exchange rate act as net volatility recipients. Full article

The hanging of hard roofs in coal seams poses a significant threat to the safe mining of coal. Hydraulic fracturing is an important method to achieve the pre-weakening of coal seam roofs. Clarifying the scope of hydraulic fracturing in coal seam roofs and its influencing factors is a prerequisite for ensuring the effectiveness of the pre-weakening process. In this paper, we developed a fluid–structure coupling numerical simulation model for hydraulic fracturing based on the element damage theory, and have systematically examined the effects of both engineering parameters and geological factors on the hydraulic fracture propagation behavior of the segmented fracturing of coal seam roofs. Results indicate that increasing the injection rate can significantly enhance fracture propagation length. A larger stress difference directs fractures along the maximum principal stress direction and effectively extends their length. Additionally, increasing the spacing between fracture stages reduces stress interference between clusters, leading to a transition from asymmetric to uniform fracture propagation. To validate the numerical simulation results, we conducted a field test on the hydraulic fracturing of the coal seam roof, and monitored the affected area by using transient electromagnetic and microseismic monitoring techniques. Monitoring results indicated that the effective impact range of field hydraulic fracturing was consistent with the numerical simulation results. Through the systematic monitoring of support resistance and coal body stress, the supporting resistance in the fractured zone decreased by 25.10%, and the coal seam stress in the fractured zone exhibited a 1 MPa reduction. Observations demonstrate the significant effectiveness of hydraulic fracturing in regional control of the coal seam roof. This study combines numerical simulation with engineering practice to investigate hydraulic fracturing performance under varying operational conditions, with the findings providing robust technical support for safe and efficient mining production. Full article

Enhanced or engineered geothermal systems (EGSs), or non-hydrothermal resources, are highly notable among sustainable energy resources because of their abundance and cleanness. The EGS concept has received worldwide attention and undergone intensive studies in the last decade in the US and around the world. In comparison, hydrothermal reservoir resources, the ‘low-hanging fruit’ of geothermal energy, are very limited in amount or availability, while EGSs are extensive and have great potential to supply the entire world with the needed energy almost permanently. The EGS, in essence, is an engineered subsurface heat mining concept, where water or another suitable heat exchange fluid is injected into hot formations to extract heat from the hot dry rock (HDR). Specifically, the EGS relies on the principle that injected water, or another working fluid, penetrates deep into reservoirs through fractures or high-permeability channels to absorb large quantities of thermal energy by contact with the host hot rock. Finally, the heated fluid is produced through production wells for electricity generation or other usages. Heat mining from fractured EGS reservoirs is subject to complex interactions within the reservoir rock, involving high-temperature heat exchange, multi-phase flow, rock deformation, and chemical reactions under thermal-hydrological-mechanical (THM) processes or thermal-hydrological-mechanical-chemical (THMC) interactions. In this paper, we will present a THM model and reservoir simulator and its application for simulation of hydrothermal geothermal systems and EGS reservoirs as well as a methodology of coupling thermal, hydrological, and mechanical processes. A numerical approach, based on discretizing the thermo-poro-elastic Navier equation using an integral finite difference method, is discussed. This method provides a rigorous, accurate, and efficient fully coupled methodology for the three (THM) strongly interacted processes. Several programs based on this methodology are demonstrated in the simulation cases of geothermal reservoirs, including fracture aperture enhancement, thermal stress impact, and tracer transport in a field-scale reservoir. Results are displayed to show geomechanics’ impact on fluid and heat flow in geothermal reservoirs. Full article

The dynamic and uncertain nature of financial markets presents significant challenges in accurately predicting portfolio returns due to inherent volatility and instability. This study investigates the potential of logistic regression to enhance the accuracy and robustness of return classification models, addressing challenges in dynamic portfolio optimization. We propose a price-aware logistic regression (PALR) framework to classify dynamic portfolio returns. This approach integrates price movements as key features alongside traditional portfolio optimization techniques, enabling the identification and analysis of patterns and relationships within historical financial data. Unlike conventional methods, PALR dynamically adapts to market trends by incorporating historical price data and derived indicators, leading to more accurate classification of portfolio returns. Historical market data from the Dow Jones Industrial Average (DJIA) and Hang Seng Index (HSI) were used to train and test the model. The proposed scheme achieves an accuracy of 99.88%, a mean squared error (MSE) of 0.0006, and an AUC of 99.94% on the DJIA dataset. When evaluated on the HSI dataset, it attains a classification accuracy of 99.89%, an AUC of 99.89%, and an MSE of 0.011. The results demonstrate that PALR significantly improves classification accuracy and AUC while reducing MSE compared to conventional techniques. The proposed PALR model serves as a valuable tool for return classification and optimization, enabling investors, assets, and portfolio managers to make more informed and effective decisions. Full article

Studies of positional (=locomotor and postural) behavior are central to understanding how animals interact with the challenges imposed by their environment and are crucial for conservation management. The present study investigates, for the first time, the positional behavior and substrate use of the endangered southern pygmy slow loris Xanthonycticebus pygmaeus. Despite their very specialized morphology and ecology, the positional behavior of lorises is understudied. Behavioral data were collected using 30-s scan instant sampling on seven captive animals housed in a large, enriched enclosure of the Poznań Nowe Zoo (Poland) during February–June 2013. Pygmy slow lorises were almost exclusively arboreal and most activities occurred on multiple substrates (82.93%). Small (57.91%) and large (28.28%) substrates were extensively used. Horizontal (42.11%) and oblique (38.47%) substrates dominated. Clamber (39.39%), quadrupedalism (33.77%), and vertical climb (17.62%) were the main locomotor modes. Standing was the dominant posture (47.23%), followed by hanging (27.32%) and clinging (11.31%). Our results concur with the limited observations available on other lorisines; pygmy slow lorises employed a diverse and flexible positional repertoire as an adaptation to the exploitation of the continuous forest layers with intertwined small substrates of various inclinations. Consequently, protecting and managing these habitats, supported by ex situ reintroduction programs, can effectively contribute to the conservation of the species’ populations. Full article