Search Results (14,181)

The requirement to improve energy efficiency is constantly driving the development of high-performance and eco-friendly friction modifiers (FMs). Herein, two innovative sulfur- and phosphorus-free melamine long-chain alcohol esters (Dodec-EG-CC and Dodec-CC) are reported as novel organic friction modifiers (OFMs). Over a wide temperature range of 100 °C to 200 °C, the synthesized melamine long-chain alcohol esters, which have exceptional thermal stability, dramatically lessen wear and friction of PAO4 base oil. Dodec-EG-CC particularly reduces friction by up to 50% and wear rate by approximately 92% within this temperature range. Detailed studies of the tribological properties at elevated temperatures demonstrate that the synergistic effect of the melamine structural unit coupled with ester groups significantly enhances adsorption properties of additives on metal surfaces, improving adsorption strength and lubricating film stability. The adsorption of additives on the metal surfaces is further confirmed by surface analysis and adsorption energy calculation, which serve as a key parameter for characterizing the binding strength between molecules and surfaces. These findings demonstrate the potential of the designed triazine-based derivatives, especially Dodec-EG-CC, as OFMs in effectively reducing friction losses in motor vehicle engines. This highlights their significant potential for industrial applications in improving energy efficiency and extending engine lifespan. These in-depth studies not only provide valuable insights for the molecular structure design of OFMs, but also advances the development of sustainable lubrication technologies. Full article

In the context of wheelchair racing, research primarily focuses on studying wheelchair ergonomics and determining kinematic, kinetic, and rolling resistance variables. One factor identified as influencing athletes’ performance is wheel skidding on the ground, a parameter complementary to rolling resistance. The objective of this study, therefore, is to identify, within a laboratory setting, the parameters that influence the risk of skidding in racing wheelchairs by measuring skidding torque. The ultimate goal is to enhance athletes’ performance by optimizing the interaction between the athlete and their wheelchair, and the wheelchair and the environment. In this perspective, four parameters were examined: the type of tubular, the camber angle, the tire pressure, and the load applied to the wheel using a skidometer. This tool characterizes a tire’s grip on a surface by measuring torques. The aim is to develop a system for classifying tire grip on dry athletics track at ambient temperature. The findings revealed that only the effects of load and tubular type had a significant impact on the torque values obtained. The tire that minimized the risk of skidding, among all tested combinations, is the Vittoria Pista Speed 23–28″. Furthermore, as the mass applied to the wheel increases, so do the resulting torques. This implies that a heavier athlete would require a greater force to be applied to the hand rim for the tire to skid. However, it was also demonstrated that the risk of skidding in a racing wheelchair is unlikely, as the torques obtained were over a range of 90 to 190 Nm. These values far exceed those typically exerted by para-athletes, which are a maximum of 60 Nm. The long-term goal would be to adjust the mode of torque application on the wheel using the skidometer for a more realistic field approach. Full article

Sorption isotherms enable postharvest technologists to estimate the degree and rate of drying of agricultural produce. They are also useful in the design and operation of desiccant systems that are used to condition air. However, the published data on sorption isotherms contain several inconsistencies. For example, under the conditions considered in this work, it is shown that the widely cited Chung–Pfost isotherm predicts moisture contents of canola that are less than zero as the relative humidity tends to zero. Furthermore, it is shown that a long-established form of empirical expression appears to grossly overestimate the differential heat of wetting, hence the integral heat of wetting of canola. In this work, algebraic expressions are derived that enable the relationship between the forms of isotherm equations on the speed of drying to be calculated. Prima facie, it is anticipated the heat of adsorption will augment the speed of temperature waves through beds of drying canola. However, it is found that this may not be the case. Anomalies in published isotherms for agricultural produce reinforce the need for accurate psychometric data to be measured over a wide range of temperatures and relative humidities. Full article

In this paper, we present a multi-sensor platform for predictive maintenance featuring hybrid long-range (LoRa) and 5G connectivity. This hybrid approach combines LoRa’s low-power transmission for energy efficiency with 5G’s real-time data capabilities. The hardware platform integrates multiple sensors to monitor machine health parameters, with data analyzed on the device using pre-trained AI models to assess the machine’s condition. Inferences are transmitted via LoRa to the operator for maintenance scheduling, while a cloud application tracks and stores sensor data. Periodic sensor data bursts are sent via 5G to update the AI model, which is then delivered back to the platform through over-the-air (OTA) updates. We provide a comprehensive overview of the hardware architecture, along with an in-depth analysis of the data generated by the sensors, and its processing methodology. However, the data analysis and the software for ventilation control and its predictive capabilities are not the focus of this paper and are not presented. Full article

Background: Groin pain is a complex and multifactorial condition commonly observed in athletes, often impairing performance and quality of life. While conservative treatments are the first-line approach, the variability in intervention protocols and inconsistent evidence necessitate a comprehensive synthesis of current knowledge. Methods: This narrative review analyzed the available literature on conservative management of groin pain in athletes. A systematic search was conducted across the MEDLINE, Cochrane CENTRAL, Scopus, PEDro, and Web of Science databases. Studies focusing on pain reduction, functional recovery, return-to-sport outcomes, and prevention strategies were included. Findings were synthesized to evaluate the efficacy of conservative interventions and identify gaps in the evidence. Results: Conservative treatments, particularly active rehabilitation and multimodal therapy, demonstrated significant efficacy in reducing pain (50–80%) and improving function, as measured by tools such as the HAGOS score. Return-to-sport rates ranged from 70% to 90%, depending on intervention type and adherence. Screening tools, including the adductor squeeze test, were effective in predicting and preventing groin injuries. However, variability in methodologies, small sample sizes, and a lack of long-term follow-up limited the generalizability of the findings. Conclusions: Conservative management remains a cornerstone for treating groin pain in athletes, offering effective outcomes for pain reduction, functional recovery, and injury prevention. However, standardized protocols and high-quality research are needed to enhance clinical guidance and optimize patient outcomes. Full article

Objective: This study aimed to evaluate the outcomes and predictive factors of I-125 radioactive plaque therapy for recurrent and refractory retinoblastoma (Rb) cases that failed primary systemic chemotherapy and focal therapies. Methods: A retrospective study of 20 eyes with intraocular Rb treated with I-125 radioactive plaque therapy (Apex dose 45 Gy) from 2013 to 2023 was conducted. Data on tumor characteristics, treatments, and outcomes were collected over a follow-up period of at least one year. Results: There were 11 (55%) males and 8 (40%) patients who had bilateral disease. All 20 treated eyes (100%) showed initial tumor regression, while long-term tumor control and eye salvage were achieved in 14 eyes (70%). Six eyes (30%) experienced uncontrollable tumor recurrence after a mean of 6 months (range: 3–12 months) after plaque therapy. Recurrence included main tumor activity in six eyes and additional resistant vitreous seeds in two of them. Poor predictive factors for eye salvage included Group D at diagnosis (p = 0.044), active vitreous seeds at the time of plaque therapy ((p = 0.045), tumor thickness >5.0 mm (p = 0.045), and tumor base dimension >12 mm (p = 0.023). Post-plaque complications included cataracts in seven eyes (35%), tumor hemorrhage in six eyes (30%), retinal detachment in four eyes (20%), radiation retinopathy in three eyes (15%), and neovascular glaucoma in one eye (5%). Five (83%) of those with tumor hemorrhage had plaque surgery performed within less than 6 months of the last cycle of systemic chemotherapy. At a mean follow-up of 36 months (range: 12–96 months), five eyes (25%) were enucleated, and high-risk pathological features were identified in three eyes, including post-laminar optic nerve infiltration (one eye) and massive choroidal invasion (two eyes). All patients were alive and free of metastasis except one patient (5%) whose parents refused enucleation and came back with extra-scleral extension and bone marrow metastasis and eventually passed away. Conclusions: I-125 radioactive plaque therapy is a valuable salvage treatment for recurrent and refractory retinoblastoma, achieving tumor control and eye salvage in 70% of cases with an acceptable safety profile. However, the observed recurrence rate (30%) at an apex dose of 45 Gy suggests a need for dose optimization and individualized treatment strategies. Identifying high-risk features, such as Group D disease, active vitreous seeds, and larger tumors, is crucial for patient selection and outcome prediction. Future research should explore alternative dosing strategies, combination therapies, and improved predictive models to enhance long-term tumor control while minimizing complications. Full article

This study examines the out-of-sample predictability of expected skewness of oil price returns, which serves as a metric for global future risks, as we show statistically through the association with crises of different nature, for stock returns of 10 (8 advanced plus two emerging) countries using long-range monthly data of over a century for each country. Using a distributed lag predictive econometric model, which controls for endogeneity, persistence, and conditional heteroscedasticity, we provide evidence of the strong statistical significance of the predictive impact of the third moment of oil price returns for equity returns for all the countries across various forecast horizons and the length of out-of-sample periods. These findings also hold for the shorter sample periods of 3 other emerging markets: Brazil, China, and Russia. Our findings have important implications for academics, investors, and policymakers. Full article

Power systems hold huge potential for emission reduction, which has made the modeling and pathway simulations of their decarbonizing development a subject of widespread interest. However, current studies have not yet provided a useful modeling method that can deliver analytical probabilistic information about future system behaviors by considering various uncertainty factors. Therefore, this paper proposes a stochastic process-based approach that can provide analytical solutions for the uncertainty ranges, as well as their changing momentum, accumulation, and probabilistic distributions. Quantitative probabilities of certain incidents in power systems can be deduced accordingly, without massive Monte Carlo simulations. A case study on China’s long-term coal-fired power phaseout was conducted to demonstrate the practical use of the proposed approach. By modeling the coal-fired power system at the unit level based on stochastic processes, phaseout pathways are probabilistically simulated with consideration of national power security. Simulations span from 2025 to 2060, presenting results and accumulated uncertainties for annual power amounts, full-process emissions, and carbon efficiencies. Through this modeling and simulation, the probabilities of China’s coal-fired power system achieving carbon peaking by 2030 and carbon neutrality by 2060 are 91.15% and 42.13%, respectively. It is expected that there will remain 442 GW of capacity with 0.18 Gt of carbon emissions in 2060. Full article

The sulfide Pb–Zn deposits in the Aksai Chin region of Xinjiang have long been subject to debate regarding their genetic classification due to the unclear origin of the ore-forming components. This study focuses on the Sachakou Pb–Zn deposit, the most representative deposit in the region, and integrates field investigations, petrographic observations, in situ LA-ICP-MS trace element analysis, and in situ S–Pb isotope analysis. The deposit is hosted within the siliceous rock and silicified limestone of the Lower Jurassic Bagongbulansha Formation, with ore bodies controlled by structural and stratigraphic factors. Three mineralization stages have been identified in the Sachakou deposit: a red–brown sphalerite mineralization stage (S1), a light-brown sphalerite stage (S2), and a galena mineralization stage (S3). The trace elements in sphalerite indicate that the mineralization process is unrelated to magmatic activity. The mineralization temperature, determined using a GGIMFis geothermometer, ranges from 294 °C to 121 °C. The δ³⁴S_V-CDT values of sulfides range from −4.93‰ to 1.24‰, suggesting that the Jurassic gypsum layer served as the sulfur source. The lead isotope ratios of ²⁰⁶Pb/²⁰⁴Pb range from 18.308 to 18.395, of ²⁰⁷Pb/²⁰⁴Pb—from 15.669 to 15.731, and of ²⁰⁸Pb/²⁰⁴Pb—from 38.595 to 38.776, indicating that the ore-forming metals were predominantly sourced from the upper crust. Based on geological and geochemical characteristics, the Sachakou Pb–Zn deposit is classified as a sedimentary-hosted epizonogenic hydrothermal deposit. Full article

The viscoelastic behavior of asphalt mixtures is a crucial consideration in the analysis of pavement mechanical responses and structural design. This study aims to elucidate the molecular structure and component evolution trends of polyphosphoric acid (PPA)/styrene butadiene styrene block copolymer (SBS)/styrene butadiene rubber copolymer (SBR) composite modified asphalt (CMA) under rolling thin film oven test (RTFOT) and pressure aging (PAV) conditions, as well as to analyze the viscoelastic evolution of CMA mixtures. First, accelerated aging was conducted in the laboratory through RTFOT, along with PAV tests for 20 h and 40 h. Next, the microscopic characteristics of the binder at different aging stages were explored using Fourier-transform infrared spectroscopy (FTIR) and gel permeation chromatography (GPC) tests. Additionally, fundamental rheological properties and temperature sweep tests were performed to reveal the viscoelastic evolution characteristics of CMA. Ultimately, the viscoelastic properties of CMA mixtures under dynamic loading at different aging stages were clarified. The results indicate that the incorporation of SBS and SBR increased the levels of carbonyl and sulfoxide factors while decreasing the level of long-chain factors, which slowed down the rate of change of large molecule content and reduced the rate of change of LMS by more than 6%, with the rate of change of overall molecular weight distribution narrowing to below 50%. The simultaneous incorporation of SBS and SBR into CMA mixtures enhanced the dynamic modulus in the 25 Hz and −10 °C range by 24.3% (AC-13), 15.4% (AC-16), and reduced the $\phi$ by 55.8% (AC-13), 40% (AC-16). This research provides a reference for the application of CMA mixtures in the repair of pavement pothole damage. Full article

Background: Femoroacetabular Impingement Syndrome (FAIS) is a musculoskeletal disorder characterized by hip pain, reduced range of motion (ROM), and functional impairment, particularly in young and physically active individuals. While surgery is generally not performed in individuals under 18 due to skeletal immaturity, it remains a standard treatment option for adults presenting with persistent symptoms and functional limitations. However, the overall effectiveness of physiotherapy-based interventions remains unclear. This review aimed to evaluate the effectiveness of conservative rehabilitation strategies for FAIS, assessing their impact on pain management, functional improvement, and quality-of-life outcomes, rather than directly comparing them to surgical interventions. Methods: This scoping review was conducted following the Joanna Briggs Institute (JBI) framework and PRISMA-ScR guidelines. A systematic literature search was performed in PubMed, Cochrane CENTRAL, Scopus, PEDro, and Web of Science. Studies were included if they examined conservative rehabilitation for FAIS, assessing outcomes such as pain reduction, functional improvement, range of motion (ROM), muscle strength, and quality of life. Data were extracted and synthesized narratively. Results: Both conservative rehabilitation and surgical intervention resulted in significant improvements in pain, function, and quality of life. Exercise-based physiotherapy, particularly programs incorporating core stability, progressive strengthening, and neuromuscular training, demonstrated positive outcomes. Surgery provided faster pain relief, ROM improvements, and earlier functional gains, particularly in activities requiring hip flexion. Given the variability in outcome measures, including pain, function, and quality of life, the interpretation of results must consider differences in treatment protocols across studies. Conclusions: Conservative rehabilitation should be considered a first-line treatment for Femoroacetabular Impingement Syndrome (FAIS), as it provides significant improvements in pain relief, function, and quality of life while mitigating the risks associated with surgery. Exercise-based physiotherapy, particularly programs incorporating core stabilization, progressive strengthening, and neuromuscular training, has demonstrated positive clinical outcomes. Although surgery may offer faster symptom relief and greater short-term functional gains, long-term differences between surgical and conservative management appear minimal in selected patient populations. Structured physiotherapy interventions should be prioritized before surgical consideration, except in cases where symptoms persist despite adequate rehabilitation. Future research should aim to establish standardized rehabilitation protocols, define optimal intervention parameters, and identify patient subgroups most likely to benefit from conservative management. Additionally, longitudinal studies with larger sample sizes are needed to clarify the long-term effects of non-surgical treatments on joint health and functional outcomes. Full article

Research into, and the usage of, Low-Power Wide-Area Networks (LPWANs) has increased significantly to support the ever-expanding requirements set by IoT applications. Specifically, the usage of Long-Range Wide-Area Networks (LoRaWANs) has increased, due to the LPWAN’s robust physical layer, Long-Range (LoRa), modulation scheme, which enables scalable, low-power consumption, long-range communication to IoT devices. The LoRaWAN Medium Access Control (MAC) protocol is currently limited to only support single-hop communication. This limits the coverage of a single gateway and increases the power consumption of devices which are located at the edge of a gateway’s coverage range. There is currently no standardised and commercialised multi-hop LoRa-based network, and the field is experiencing ongoing research. In this work, we propose a complementary network to LoRaWAN, which integrates mesh networking. An ns-3 simulation model has been developed, and the proposed LoRaMesh network is simulated for a varying number of scenarios. This research focuses on the design decisions needed to design a LoRa-based mesh network which maintains the low-power consumption advantages that LoRaWAN offers while ensuring that data packets are routed successfully to the gateway. The results highlighted a significant increase in the packet delivery ratio in nodes located far from a centralised gateway in a dense network. Nodes located further than 5.8 km from a gateway’s packet delivery ratio were increased from an average of 40.2% to 73.78%. The findings in this article validate the concept of a mesh-type LPWAN network based on the LoRa physical layer and highlight the potential for future optimisation. Full article

Glacier meltwater influences streamflow and various activities in the western US. The Wind River Range (WRR) in Wyoming, which contains the largest glacial mass in the Rocky Mountains of the conterminous US, has been retreating since the Little Ice Age. This study examines long-term changes in WRR glaciers (>0.2 km²) over 1968–2019 and investigates their relationship with climatic and topographic factors. Using USGS topographic maps, satellite imagery, DEM datasets, and GPS surveys, we analyzed glacier area and surface elevation changes. Our results show a 19.2 ± 0.9% glacier area reduction from 1972 to 2019, with a 10.6 ± 0.3% decline from 2000–2019. Glacier thinning was most pronounced between 2000 and 2019 at −0.58 ± 0.11 m y⁻¹, with lower-elevation glaciers thinning faster. Small, south-facing glaciers retreated more rapidly, while slope effects were mixed. Increasing spring temperatures and a shift toward more spring precipitation falling as rain has likely exacerbated glacier loss since 2000. Such accelerated melting has significant implications for water availability and ecosystem health if warming continues, affecting agricultural, industrial, and recreational water use. Understanding these trends is key for future water resource management and ecosystem sustainability in the region. Full article

Given a question–image input, a visual commonsense reasoning (VCR) model predicts an answer with a corresponding rationale, which requires inference abilities based on real-world knowledge. The VCR task, which calls for exploiting multi-source information as well as learning different levels of understanding and extensive commonsense knowledge, is a cognition-level scene understanding challenge. The VCR task has aroused researchers’ interests due to its wide range of applications, including visual question answering, automated vehicle systems, and clinical decision support. Previous approaches to solving the VCR task have generally relied on pre-training or exploiting memory with long-term dependency relationship-encoded models. However, these approaches suffer from a lack of generalizability and a loss of information in long sequences. In this work, we propose a parallel attention-based cognitive VCR network, termed PAVCR, which fuses visual–textual information efficiently and encodes semantic information in parallel to enable the model to capture rich information for cognition-level inference. Extensive experiments show that the proposed model yields significant improvements over existing methods on the benchmark VCR dataset. Moreover, the proposed model provides an intuitive interpretation of visual commonsense reasoning. Full article

The high-magnetic anomaly belt in the northern slope of the South China Sea has long been associated with a Mesozoic volcanic arc. However, its crustal architecture remains unclear, limiting the understanding of its geological implications. We assembled high-resolution reduced-to-the-pole aeromagnetic anomaly data around the northern South China Sea and then applied the 3-D magnetic inversion method based on mixed L_p norm regularization, with the constraint of multiple deep seismic reflection profiling data, to obtain high-resolution 3-D crustal susceptibility model. Our model confirms that the high-magnetic anomaly belt is caused by deep-seated magnetic bodies, which, supported by borehole and seismic data, are identified as a Mesozoic volcanic arc. We found that the Mesozoic volcanic arc described by high susceptibility bodies extends northeastward from the Dongsha Rise to Taiwan Island and primarily distributes within the depth range of 20~28 km. Our findings provide important constraints for understanding the pre-Cenozoic tectonic evolution of the northern South China Sea. Full article