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AbstractThe core component of the ground source heat pump (GSHP) system is the buried pipe heat exchanger. It is critically important to analyze its thermal exchange efficiency for safe and consistent functionality. Taking the double U-shaped buried pipe group as the study subject, this research constructed a three-dimensional model using computational fluid dynamics (CFD). The influence of the spacing and drilling depth on the heat transfer performance was analyzed. Further investigation was conducted on how 15 years of uninterrupted operation of the buried pipes affects the temperature field of the surrounding soil. The spacings between buried pipes were set to 4 m, 4.5 m, 5 m, 5.5 m, and 6 m, with drilling depths fixed at 150 m and 200 m. The research findings indicated that an optimal spacing of 5 m and a depth of 150 m were identified. Following a continuous 15-year period of operation, the mean temperature of the soil reached 15.5 °C. This represents a modest increase of just 0.45 °C when compared to the initial soil temperature, demonstrating effective soil temperature recovery and the absence of heat or cold accumulation. This study provides references for the design and construction of double U-shaped buried pipes in the GSHP system. [ABSTRACT FROM AUTHOR]

In order to understand the distribution of streaming potentials in cartilage pores, this paper established finite element model to analyze. The results showed that the streaming potential in cartilage micro-pores increased along the axis. The electric potential in 5 μm straight micro-pore was about 50 μV, and the electric potential of curved bifurcation model was about 30 μV. The pressure and Zeta potential had a linear growth relationship with the streaming potential. The streaming potential decreased with the increase of ion concentration until ion concentration was saturated. These results could provide a theoretical basis for cartilage research. [ABSTRACT FROM AUTHOR]

[Display omitted] • A multi-energy complementary heating system (MECHS) suitable for cold rural areas was built. • The MECHS was assessed using the entropy-TOPSIS model, with economic factor contributing more than 50%. • Solar-biomass was the optimal heating mode and had a comprehensive score of 0.6202. The establishment of a multi-energy complementary heating system (MECHS) using abundant renewable energy is currently an effective way to solve the rapid growth of heating demands in rural areas. However, coupling schemes for different energy sources have become a critical barrier to the MECHS development. The entropy-TOPSIS method was used to conduct a comprehensive evaluation of MECHS, which provided a basis for optimizing system operation strategy. We built a test platform for MECHS based on solar-biomass-electricity energy in Tumxuk, Northwest China. Frist, six working modes were established according to the system operation control strategy. Second, we constructed the evaluation indexes of MECHS considering energy, environment and economy and determined their weights using entropy weight method. Third, the TOPSIS model was used to perform a comprehensive evaluation of the different working modes to identify optimal energy supply schemes. Our case study showed that the MECHS operated stably and met the indoor temperature demands of rural houses in cold regions. To maximize the heating efficiency of the system, it is necessary to reduce the types of energy appropriately. Next, based on entropy-TOPSIS model, the recommended order of energy supply mode for heating systems were solar-biomass energy (0.6202), solar-biomass-electric energy (0.6152), solar-electric energy (0.5895), biomass energy (0.4075), biomass-electric energy (0.3680), and electrical energy (0.3603). We found that the optimal energy supply mode was solar-biomass. Our results indicated that the entropy-TOPSIS model could provide practical recommendations for the design and operation strategies of MECHS in cold rural areas. [ABSTRACT FROM AUTHOR]

Purpose: In the process of continuous casting and rolling of steel plate, due to the influence of rolling equipment and process, there are scratches, inclusions, patches, scabs and pitted surfaces on the surface of steel plate, which will not only affect the corrosion resistance, wear resistance and fatigue strength of steel plate but also may cause production accidents. Therefore, the detection of steel plate surface defect must be strengthened to ensure the production quality of steel plate and the smooth development of industrial construction. Design/methodology/approach: (1) A steel plate surface defect detection technology based on small datasets is proposed, which can detect multiple surface defects and fill in the blank of scab defect detection. (2) A detection system based on intelligent recognition technology is built. The steel plate images are collected by the front-end monitoring device, then transmitted to the back-end monitoring center and processed by the embedded intelligent algorithms. (3) In order to reduce the impact of external light on the image, an improved Multi-Scale Retinex (MSR) enhancement algorithm based on adaptive weight calculation is proposed, which lays the foundation for subsequent object segmentation and feature extraction. (4) According to the different factors such as the cause and shape, the texture and shape features are combined to classify different defects on the steel plate surface. The defect classification model is constructed and the classification results are recorded and stored, which has certain application value in the field of steel plate surface defect detection. (5) The practicability and effectiveness of the proposed method are verified by comparison with other methods, and the field running tests are conducted based on the equipment commissioning field of China Heavy Machinery Institute. Findings: When applied to small dataset, the precision of the proposed method is 94.5% and the time is 23.7 ms. In order to compare with deep learning technology, after expanding the image dataset, the precision and detection time of this paper are 0.948 and 24.2 ms, respectively. The proposed method is superior to other traditional image processing and deep learning methods. And the field recognition precision is 91.7%. Originality/value: In brief, the steel plate surface defect detection technology based on computer vision is effective, but the previous attempts and methods are not comprehensive and the accuracy and detection speed need to be improved. Therefore, a more practical and comprehensive technology is developed in this paper. The main contributions are as follows: (1) A steel plate surface defect detection technology based on small datasets is proposed, which can detect multiple surface defects and fill in the blank of scab defect detection. (2) A detection system based on intelligent recognition technology is built. The steel plate images are collected by the front-end monitoring device, then transmitted to the back-end monitoring center and processed by the embedded intelligent algorithms. (3) In order to reduce the impact of external light on the image, an improved MSR enhancement algorithm based on adaptive weight calculation is proposed, which lays the foundation for subsequent object segmentation and feature extraction. (4) According to the different factors such as the cause and shape, the texture and shape features are combined to classify different defects on the steel plate surface. The defect classification model is constructed and the classification results are recorded and stored, which has certain application value in the field of steel plate surface defect detection. (5) The practicability and effectiveness of the proposed method are verified by comparison with other methods, and the field running tests are conducted based on the equipment commissioning field of China Heavy Machinery Institute. [ABSTRACT FROM AUTHOR]

Multi-energy complementary heating (MECH) is the most promising and potential heating technology of the future. However, owing to the increase in energy types, the system is complex, and the operation procedure cumbersome. In addition, due to the uncertainty of climate conditions, it is difficult to develop a general control strategy suitable for all heating systems. In order to study the optimal control strategy of MECH systems with solar, biomass, and electric energy as three heat sources in cold regions, the system heating was tested over different periods during the entire heating season for rural residential buildings in cold regions, and the operating performance of the system was evaluated. The MECH experiment, based on the optimal control strategy, was compared with other different heating systems, and the economic and environmental benefits of the system were further evaluated. The results showed that, compared with room temperature control strategy (RS-CON), the control strategy of the heat storage tank (HST-CON) with sufficient solar energy (SE) can afford a higher solar fraction by 10%, more HST heating hours, and lower operating costs and CO2 emissions. During heating operation, Mode 3 [biomass boiler (BB) + heat storage tank (HST) heating] was the best heating mode. At the end of the heating period, Mode 5 (HST heating) met the indoor heat demand and had a significant energy-saving effect. From the perspective of the whole heating season, HST-CON heating operation can generate lower energy consumption costs and achieve almost zero CO2 emissions. This study is of great significance because it provides an engineering reference for the rational the utilization of MECH systems in cold regions. [ABSTRACT FROM AUTHOR]

Objective: FK866 is an inhibitor of nicotinamide phosphoribosyltransferase (NAMPT), which exhibits neuroprotective effects in ischemic brain injury. However, in traumatic brain injury (TBI), the role and mechanism of FK866 remain unclear. The present research was aimed to investigate whether FK866 could attenuate TBI and clarified the underlying mechanisms. Methods: A controlled cortical impact model was established, and FK866 at a dose of 5 mg/kg was administered intraperitoneally at 1 h and 6 h, then twice per day post‐TBI until sacrifice. Brain water content, Evans blue dye extravasation, modified neurological severity scores (mNSS), Morris water maze test, enzyme‐linked immunosorbent assay (ELISA), immunofluorescence staining, and western blot were performed. Results: The results demonstrated that FK866 significantly mitigated the brain edema, blood–brain barrier (BBB) disruption, and ameliorated the neurological function post‐TBI. Moreover, FK866 decreased the number of Iba‐1‐positive cells, GFAP‐positive astrocytes, and AQP4‐positive cells. FK866 reduced the protein levels of proinflammatory cytokines and inhibited NF‐κB from translocation to the nucleus. FK866 upregulated the expression of Bcl‐2, diminished the expression of Bax and caspase 3, and the number of apoptotic cells. Moreover, p38 MAPK and ERK activation were significantly inhibited by FK866. Interpretation: FK866 attenuated TBI‐induced neuroinflammation and apoptosis, at least in part, through p38/ERK MAPKs signaling pathway. [ABSTRACT FROM AUTHOR]

The United States is the world's second‐largest producer and consumer of plastics and the largest producer of plastic waste. Understanding the sources, drivers, and destinations of plastic production, consumption, and waste is critical for the United States to develop strategies toward a zero‐plastic pollution future. Here, we characterize the dynamic material flows and stocks of plastics in the United States for nearly seven decades (1950–2018) and project the future trajectories until 2050 under various scenarios on the basis of reduce, reuse, and recycle to explore pathways toward zero plastic pollution. Our estimation shows that 1479 MMt plastics were produced in the United States from 1950 to 2018, 75 MMt waste plastics were domestically recycled, 139 MMt virgin polymers were exported, and 9 MMt recycled waste plastics were imported. Currently, about 326 MMt of plastics still remain in the society as in‐use stock, most of which (63%) are in the construction sector. Plastic pollution would almost double from 37 MMt in 2018 to 86 MMt in 2050 if current consumption pattern and waste management remain unchanged. Single strategies (i.e., plastic bag ban and extended lifespan) could only contribute limited reductions (2%–12%) of plastics pollution, and would not be able to reverse the increasing trajectory of plastic pollution until 2050. Additional measures are needed, such as improving recycling and avoiding landfilling of plastic waste. Our analysis can provide critical insights to help the United States develop long‐term strategies to mitigate and eliminate plastic pollution. [ABSTRACT FROM AUTHOR]

The industrial sector is China's major element of energy consumption and carbon emissions, and carbon emissions reduction in industrial parks has become an important foothold in carbon reduction work. Predicting the future evolution trend of carbon emissions in industrial parks under different policy orientations is of great significance for China to achieve the carbon emissions peaking and carbon neutrality goals. Based on the current status of electricity consumption and carbon emissions in industrial parks, this paper takes a light industrial park as the research object, analyzes the source of carbon emissions in this park, combines the characteristics of resource endowment and industrial structure, and considers the factors influencing society, load curve, energy supply and carbon sink, thus constructing a system dynamics model of carbon emission evolution for this park. Different influencing factors are selected to set multiple target scenarios, and the GDP, carbon emissions, carbon emissions reduction and near‐zero carbon evaluation coefficient of light industrial parks are used as characterization indicators for simulation analysis. The analysis results revealed that the comprehensive scenario set by increasing the maximum installed capacity of renewable energy units and raising the proportions of environmental and science and technology inputs while adjusting the industrial growth rate of the park performed best. In this scenario, the economic development of the park and the process of carbon emissions reduction are considered. [ABSTRACT FROM AUTHOR]

Background/Aims: Spinal cord injury (SCI) is a serious global problem that leads to permanent motor and sensory deficits. This study explores the anti-apoptotic and neuroprotective effects of the natural extract β-elemene in vitro and in a rat model of SCI. Methods: CCK-8 assay was used to evaluate cell viability and lactate dehydrogenase assay was used to evaluate cytotoxicity. A model of cell injury was established using cobalt chloride. Apoptosis was evaluated using a fluorescence-activated cell sorting assay of annexin V-FITC and propidium iodide staining. A rat SCI model was created via the modified Allen’s method and Basso, Beattie, and Bresnahan (BBB) scores were used to assess locomotor function. Inflammatory responses were assessed via enzyme-linked immunosorbent assay (ELISA). Apoptotic and surviving neurons in the ventral horn were respectively observed via terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining and Nissl staining. Western blotting was used to measure protein expression. Results: β-elemene (20 μg/ml) promoted cell viability by activating phosphorylation of the PI3K-AKT-mTOR pathway. β-elemene reduced CoCl2-induced cellular death and apoptosis by suppressing the expression levels of CHOP, cleaved-caspase 12, 78-kilodalton glucose-regulated protein, cleaved-caspase 3, and the Bax/Bcl-2 ratio. In the rat model of SCI, Nissl and TUNEL staining showed that β-elemene promoted motor neuron survival and reduced neuronal apoptosis in the spinal cord ventral horn. BBB scores showed that β-elemene significantly promoted locomotor behavioral recovery after SCI. In addition, β-elemene reduced the ELISA-detected secretion of interleukin (IL)-6 and IL-1β. Conclusion: β-elemene reduces neuronal apoptosis by alleviating endoplasmic reticulum stress in vitro and in vivo. In addition, β-elemene promotes locomotor function recovery and tissue repair in SCI rats. Thus, our study provides a novel encouraging strategy for the potential treatment of β-elemene in SCI patients. [ABSTRACT FROM AUTHOR]

Simple Summary: Apostichopus japonicus is a temperate marine invertebrate and an economically important aquatic echinoderm species in China. As a benthic organism, sea cucumbers feed on small benthic particulate matter and are easily affected by pollutants. Therefore, for conservation purposes, it is important to elucidate the effects of specific pollutants on these animals. Bisphenol A (BPA) has been identified as an endocrine disruptor that functions as an estrogen analog and typically causes reproductive toxicity by interfering with the endocrine system. We identified the G protein-coupled estrogen receptor 1 in A. japonicus and found that both BPA and estradiol could activate the estrogen-receptor-mediated mitogen-activated protein kinase signaling pathway. Using biological approaches, we have confirmed the estrogen-analog bioactivity of BPA on sea cucumbers by direct interaction with the estrogen receptor. We also determined that BPA affects the reproduction of sea cucumbers by metabolic disruption in ovary tissue. The sea cucumber, Apostichopus japonicus, is a marine benthic organism that feeds on small benthic particulate matter and is easily affected by pollutants. Bisphenol A (BPA, 4,4′-isopropylidenediphenol) has been identified as an endocrine disruptor. It is ubiquitously detectable in oceans and affects a variety of marine animals. It functions as an estrogen analog and typically causes reproductive toxicity by interfering with the endocrine system. To comparatively analyze the reproductive effects of estradiol (E2) and BPA on sea cucumbers, we identified a G protein-coupled estrogen receptor 1 (GPER1) in A. japonicus and investigated its effects on reproduction. The results showed that BPA and E2 exposure activated A. japonicus AjGPER1, thereby mediating the mitogen-activated protein kinase signaling pathways. High-level expression of AjGPER1 in the ovarian tissue was confirmed by qPCR. Furthermore, metabolic changes were induced by 100 nM (22.83 μg/L) BPA exposure in the ovarian tissue, leading to a notable increase in the activities of trehalase and phosphofructokinase. Overall, our findings suggest that AjGPER1 is directly activated by BPA and affects sea cucumber reproduction by disrupting ovarian tissue metabolism, suggesting that marine pollutants pose a threat to the conservation of sea cucumber resources. [ABSTRACT FROM AUTHOR]

Subway stations are typically equipped with fresh air shafts to introduce outdoor air, while the surrounding rock and air channels form a vertical earth-air heat exchanger (VEAHE). This study is the first to analyze the year-round thermal storage and exothermic characteristics of the surrounding rock. A numerical model was developed, incorporating ground surface heat transfer and axial heat transfer within the rock. The simulation results aligned well with field test data. This model was then utilized to explore the thermal storage and release properties of the surrounding rock. The findings revealed that both z-directional and r-directional annual temperature wave affect the enclosing rock. The monthly average natural energy efficiency (NEE) and storage efficiency (SE) were determined to be 10.75% and 17.47%, respectively. Notably, the shallow rock exhibited the highest NEE but the lowest SE. The energy used for fresh air pre-treatment derives not only from the rock's current annual cycle but also from previously stored energy. Lastly, λ sr and c were identified as major influencers of NEE, while λ sr , c , and the burial depth of the shaft collectively impact the air pre-treatment process in the shaft. The findings contribute to further understanding of the thermal process in VEAHE systems. • A more comprehensive and accurate numerical model was developed. • First analyzed the thermal storage and release characteristics of the enclosing rock. • Studied the efficiency of the thermal storage and release of the surrounding rock. • Investigated the factors influencing thermal storage and release of the surrounding rock. [ABSTRACT FROM AUTHOR]

In the inductive power transfer (IPT) system, a hybrid topology with the anti-misalignment ability and load-independent output is usually used to improve the stability of the system and simplify the control scheme. However, the power distribution of the hybrid topology is uneven with misalignment, resulting in high current stresses in partial coils. In order to minimize the current stresses, a parameter design method with double-sided capacitor-inductor-inductor-inductor-capacitor compensation topology is proposed to optimize the coil currents without the effect on the output fluctuation. Finally, a 3.5-kW laboratory-scale prototype was built to validate the proposed method. The results show that the proposed parameter design method can minimize the maximum current stress significantly, and the hybrid IPT system has good performances of misalignment tolerance and load-independent output current. [ABSTRACT FROM AUTHOR]

The steady laminar natural convective heat transfer for air has been compared numerically between cavities with rectangular and triangular structures. The equations of momentum, heat, and mass transfer were solved using the finite difference method, and central difference approximations that have second-order accuracy were used; furthermore, a good convergence was guaranteed by using the successive under-relaxation method. The Prandtl number is fixed at 0.71, while the Rayleigh number and the aspect ratio of the enclosures were changed in the range of 103–106 and varied over 1, 0.5, 0.2, and 0.1, respectively. The cavity was heated from one vertical wall and cooled from one side, while the horizontal walls were insulated. The influence of the Rayleigh number and the aspect ratio of the both kinds of cavities on the rate of heat transfer was investigated. Results were presented using flow patterns and isotherms plots; additionally, local and mean Nusselt numbers are also obtained for all cases. The obtained results convey that at a certain aspect ratio, an increment in Rayleigh numbers significantly augments the heat transfer, the intensity of natural convection, and average Nusselt number. Another important finding is that conduction is the dominated mechanism when the aspect ratio is small originally, and then, as the aspect ratio increases, the role of the convection boosts, and finally, the convection is overwhelmed by the convection. It can be concluded that for a given aspect ratio, only when the Rayleigh number is large enough can it induce a significant convection. [ABSTRACT FROM AUTHOR]

Sea cucumber Apostichopus japonicus displays the typical circadian rhythms. This present study investigated the molecular regulation of clock genes, as well as monoamines and melatonin, in multiple tissues of A. japonicus , responding to the photoperiod. In order to determine their pivotal role in circadian rhythms, the crucial clock genes, namely AjClock , AjArnt1 , AjCry1 , and AjTimeless , were identified and a comprehensive analysis of their expressions across various tissues in adult A. japonicus was conducted, revealing the potential existence of central and peripheral oscillators. Results demonstrated that the tissues of polian vesicle and nerve ring exhibited significant clock gene expression associated with the orchestration of circadian regulation, and that environmental light fluctuations exerted influence on the expression of these clock genes. However, a number of genes, such as AjArnt1 and AjCry1 , maintained their circadian rhythmicity even under continuous light conditions. Moreover, we further investigated the circadian patterns of melatonin (MT), serotonin (5-HT), and dopamine (DA) secretion in A. japonicus , data that underscored the tissue-specific regulatory differences and the inherent adaptability to dynamic light environments. Collectively, these findings will provide the molecular mechanisms controlling the circadian rhythm in echinoderms and the candidate tissues playing the role of central oscillators in sea cucumbers. [Display omitted] • The molecular circadian system was identified in Apostichopus japonicus. • The polian vesicle and nerve ring were determined with roles as circadian oscillators. • A. japonicus circadian system exhibits stability. • The rhythmicity of molecular circadian system can be affected by photoperiods. [ABSTRACT FROM AUTHOR]

RhoA signaling pathway inhibitors such as Y27632 (a ROCK inhibitor) have recently been applied as treatments for spinal cord injury (SCI) because they promote neurite outgrowth and axonal regeneration in neurons. β-Elemene, a compound that is extracted from a natural plant (Curcuma zedoary), influences the expression level of RhoA protein. Whether it can promote neurite outgrowth in motor neurons or enhance locomotor recovery in SCI remains unclear. Here, we initially demonstrated that β-elemene promotes neurite outgrowth of ventral spinal cord 4.1 (VSC4.1) motoneuronal cells and primary cortical neurons. Pull-down assays showed that β-elemene significantly inhibits the activation of RhoA kinase. Western blotting assays suggested β-elemene markedly inhibits the phosphorylation of limk and confilin and significantly increases the expression level of GAP-43. Then, in a rat model of SCI, hematoxylin-eosin and myelin staining showed that β-elemene reduces the area of lesion cavity and spares the white matter. BBB scores showed β-elemene significantly promotes locomotor behavioral recovery. In addition, western blotting assays and immunofluorescence staining demonstrated that the expression level of GAP-43 is upregulated by β-elemene treatment in vivo . Thus, our study provided an encouraging novel strategy for the potential treatment of SCI patients with β-elemene. [ABSTRACT FROM AUTHOR]