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The deep learning method for natural-image object detection tasks has made tremendous progress in recent decades. However, due to multiscale targets, complex backgrounds, and high-scale small targets, methods from the field of natural images frequently fail to produce satisfactory results when applied to aerial images. To address these problems, we proposed the DET-YOLO enhancement based on YOLOv4. Initially, we employed a vision transformer to acquire highly effective global information extraction capabilities. In the transformer, we proposed deformable embedding instead of linear embedding and a full convolution feedforward network (FCFN) instead of a feedforward network in order to reduce the feature loss caused by cutting in the embedding process and improve the spatial feature extraction capability. Second, for improved multiscale feature fusion in the neck, we employed a depth direction separable deformable pyramid module (DSDP) rather than a feature pyramid network. Experiments on the DOTA, RSOD, and UCAS-AOD datasets demonstrated that our method's average accuracy (mAP) values reached 0.728, 0.952, and 0.945, respectively, which were comparable to the existing state-of-the-art methods. [ABSTRACT FROM AUTHOR]

Iron is a trace element necessary for cell growth, development, and cellular homeostasis, but insufficient or excessive level of iron is toxic. Intracellularly, sufficient amounts of iron are required for mitochondria (the center of iron utilization) to maintain their normal physiologic function. Iron deficiency impairs mitochondrial metabolism and respiratory activity, while mitochondrial iron overload promotes ROS production during mitochondrial electron transport, thus promoting potential disease development. This review provides an overview of iron homeostasis, mitochondrial iron metabolism, and how mitochondrial iron imbalances-induced mitochondrial dysfunction contribute to diseases. [ABSTRACT FROM AUTHOR]

Glass-fiber reinforced polymer (GFRP) bars are increasingly widely used in slope support instead of steel bars or steel pipes. GFRP Bars are generally connected with the slope by combining conical nut and tray, but the tray stress still lacks corresponding theoretical calculation and strength verification methods. Therefore, assuming that the tray is an equal thickness thin plate, the internal force distribution of the tray is calculated using the thin plate bending and cavity expansion theory, and compared with the finite element numerical analysis results of the tray. The calculation and analysis show that the elastic theoretical solution of internal force distribution of equal thickness tray is basically the same as the numerical simulation solution of variable thickness tray. The tray loading and free surface are controlled by hoop tensile and radial compressive stress, respectively. The inner wall of the free surface of the tray is the weakest part of the tray, and the ultimate strength of a GFRP tray is 35.81–53.00% of the standard tensile strength of Φ20 GFRP bars by distortion energy density. This theoretical method can be used for stress analysis of variable thickness trays and has played technical support for promoting the application of GFRP bars in slope support. [ABSTRACT FROM AUTHOR]

Tetracycline (TC) and arsenic contaminants are two main pollutants in aquaculture and livestock husbandry, and they have drawn worldwide attention. To address this issue, a novel N-doped carbon@magnesium silicate (CMS) was fabricated via a facile and low-cost hydrothermal route, adopting glucose and ammonia as C and N sources, respectively. The synergetic combination of carbon and magnesium silicate makes CMS possess a high surface area of 201 m2/g and abundant functional groups. Due to the abundant C- and N-containing functional groups and Mg-containing adsorptive sites, the maximum adsorption capacity values of CMS towards As(V) and TC are 498.75 mg/g and 1228.5 mg/g, respectively. The type of adsorption of As(V) and TC onto CMS is monolayer adsorption. An adsorption kinetic study revealed that the mass transfer and intraparticle process dominates the sorption rate of As(V) and TC adsorption onto CMS, respectively. Various functional groups synthetically participate in the adsorption process through complexion, π–π EDA interactions, and hydrogen bonds. This work provides a one-step, low-cost route to fabricate a N-doped carbonaceous adsorbent with a high surface area and abundant functional groups, which has great potential in the application of practical sewage treatment. [ABSTRACT FROM AUTHOR]

Extensive experiments have shown that gradient nano-grained metals have outstanding synergy of strength and ductility. However, the deformation mechanisms of gradient metals are still not fully understood due to their complicated gradient microstructure. One of the difficulties is the accurate description of the deformation of the nanocrystalline surface layer of the gradient metals. Recent experiments with a closer inspection into the surface morphology of the gradient metals reported that shear bands (strain localization) occur at the surface of the materials even under a very small, applied strain, which is in contrast to previously suggested uniform deformation. Here, a dislocation density-based computational model is developed to investigate the shear band evolution in gradient Cu to overcome the above difficulty and to clarify the above debate. The Voronoi polygon is used to establish the irregular grain structure, which has a gradual increase in grain size from the material surface to the interior. It was found that the shear band occurs at a small applied strain in the surface region of the gradient structure, and multiple shear bands are gradually formed with increasing applied load. The early appearance of shear banding and the formation of abundant shear bands resulted from the constraint of the coarse-grained interior. The number of shear bands and the uniform elongation of the gradient material were positively related, both of which increased with decreasing grain size distribution index and gradient layer thickness or increasing surface grain size. The findings are in good agreement with recent experimental observations in terms of stress-strain responses and shear band evolution. We conclude that the enhanced ductility of gradient metals originated from the gradient deformation-induced stable shear band evolution during tension. [ABSTRACT FROM AUTHOR]

Nature-based solutions (NbSs) are considered to form an innovative stormwater management approach that has living resolutions grounded in natural processes and structures. NbSs offer many other environmental benefits over traditional grey infrastructure, including reduced air pollution and climate change mitigation. This review predominantly centers on the hydrological aspect of NbSs and furnishes a condensed summary of the collective understanding about NbSs as an alternatives for stormwater management. In this study, which employed the CIMO (Context, Intervention, Mechanism, Outcome) framework, a corpus of 187 NbS-related publications (2000–2023) extracted from the Web of Science database were used, and we expounded upon the origins, objectives, and significance of NbSs in urban runoff and climate change, and the operational mechanisms of NbSs (including green roofs, permeable pavements, bioretention systems, and constructed wetlands), which are widely used in urban stormwater management, were also discussed. Additionally, the efficacy of NbSs in improving stormwater quality and quantity is discussed in depth in this study. In particular, the critical role of NbSs in reducing nutrients such as TSS, TN, TP, and COD and heavy metal pollutants such as Fe, Cu, Pb, and Zn is emphasized. Finally, the main barriers encountered in the promotion and application of NbSs in different countries and regions, including financial, technological and physical, regulatory, and public awareness, are listed, and future directions for improving and strategizing NbS implementation are proposed. This review gathered knowledge from diverse sources to provide an overview of NbSs, enhancing the comprehension of their mechanisms and applications. It underscores specific areas requiring future research attention. [ABSTRACT FROM AUTHOR]

Extensive research has shown that nanolayered structures are capable of suppressing the shear banding in metallic glass in nanoindentation experiments. However, the specific mode and mechanism of the shear banding underneath the indenter remains unknown. Also, the quantification of shear banding-induced strain localization is still a challenge. Herein, the size-dependent shear banding behavior of a CuTiZrNb high-entropy alloy-based nanolayered glass with individual layer thicknesses (h) ranging from 5 to 80 nm was systematically investigated by nanoindentation tests. It was found that the hardness of the designed structure was almost size-independent. Yet, a clear transition in the deformation modes from the cutting-like shear bands to the kinking-like ones was discovered as h decreased to 10 nm. Moreover, multiple secondary shear bands also appeared, in addition to the primary ones, in the sample with h = 10 nm. The transition leads to an obvious strain delocalization, as clearly illustrated by the proposed theoretical model, which is based on the assumption of a pure shear stress state to quantify the shear banding-induced strain localization. The strain delocalization results from the higher density of amorphous/amorphous interfaces that exhibit the change in morphology with a refined layered glass structure. [ABSTRACT FROM AUTHOR]

The formability of aluminum alloy sheet in electromagnetic impaction deformation has attracted the attention of numerous researchers for the past decades. However, the influences of die geometry and high-speed impaction electromagnetic deformation on formability have not been well established, thereby resulting in the formability of the sheet not being developed fully. In this study, the influence of die geometry on the formability of 5052 aluminum alloy in electromagnetic deformation was investigated by comparing the formability of 5052 aluminum alloys formed using a hemispherical die and a cylindrical die. The intriguing finding is that the formability of the 5052 aluminum alloy formed using a cylindrical die is considerably higher than that formed using a hemispherical die. Therefore, die geometry significantly influences the formability of 5052 aluminum alloy. The influence of die geometry on the formability of 5052 aluminum alloy in high-speed impaction electromagnetic deformation was explained in terms of strain rate, pressure stress, and stress state. This investigation enhances insight into the interaction between sheets and dies, and provides a reference for the studying influence of dies on the forming limit of sheets in high-speed impaction deformation. [ABSTRACT FROM AUTHOR]

Simple Summary: The effect of macrophages on tumor cells in the tumor microenvironment of hepatocellular carcinoma (HCC) has attracted more attention. In this study, expression levels of MMP9 and MICA were significantly elevated in macrophages and tumor cells, respectively. The IFN-γ pathway was activated in MICA+ tumor cells and MMP9+ macrophages. The interaction between MICA+ tumor cells and MMP9+ macrophages was mediated through the PROS1-AXL pathway. MMP9 was mainly expressed in M2-like macrophages. IRF1 induced the upregulation of PROS1 and MICA in HCC cells. MICA+ tumor cells stimulated the secretion of MMP9 from macrophages through the PROS1-AXL axis, thereby facilitating the proteolytic shedding of MICA into soluble MICA. This study provided valuable insights and supported the therapeutic application of AXL inhibition in HCC. Background: tumor-associated macrophages (TAMs) constitute a significant proportion of non-cancerous cells within the intricate tumor microenvironment (TME) of hepatocellular carcinoma (HCC). Understanding the communication between macrophages and tumor cells, as well as investigating potential signaling pathways, holds promise for enhancing therapeutic responses in HCC. Methods: single-cell RNA-sequencing data and bulk RNA-sequencing data were derived from open source databases Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA). Through this analysis, we elucidated the interactions between MICA+ tumor cells and MMP9+ macrophages, primarily mediated via the PROS1-AXL axis in advanced HCC. Subsequently, we employed a range of experimental techniques including lentivirus infection, recombinant protein stimulation, and AXL inhibition experiments to validate these interactions and unravel the underlying mechanisms. Results: we presented a single-cell atlas of advanced HCC, highlighting the expression patterns of MICA and MMP9 in tumor cells and macrophages, respectively. Activation of the interferon gamma (IFN-γ) signaling pathway was observed in MICA+ tumor cells and MMP9+ macrophages. We identified the existence of an interaction between MICA+ tumor cells and MMP9+ macrophages mediated via the PROS1-AXL axis. Additionally, we found MMP9+ macrophages had a positive correlation with M2-like macrophages. Subsequently, experiments validated that DNA damage not only induced MICA expression in tumor cells via IRF1, but also upregulated PROS1 levels in HCC cells, stimulating macrophages to secrete MMP9. Consequently, MMP9 led to the proteolysis of MICA. Conclusion: MICA+ HCC cells secreted PROS1, which upregulated MMP9 expression in macrophages through AXL receptors. The increased MMP9 activity resulted in the proteolytic shedding of MICA, leading to the release of soluble MICA (sMICA) and the subsequent facilitation of tumor immune escape. [ABSTRACT FROM AUTHOR]

To evaluate the secretory function of adrenal incidentaloma, this study explored the usefulness of a contrast-enhanced computed tomography (CECT)-based radiomics model for distinguishing aldosterone-producing adenoma (APA) from non-functioning adrenal adenoma (NAA). Overall, 68 APA and 60 NAA patients were randomly assigned (8:2 ratio) to either a training or a test cohort. In the training cohort, univariate and least absolute shrinkage and selection operator regression analyses were conducted to select the significant features. A logistic regression machine learning (ML) model was then constructed based on the radiomics score and clinical features. Model effectiveness was evaluated according to the receiver operating characteristic, accuracy, sensitivity, specificity, F1 score, calibration plots, and decision curve analysis. In the test cohort, the area under the curve (AUC) of the Radscore model was 0.869 [95% confidence interval (CI), 0.734–1.000], and the accuracy, sensitivity, specificity, and F1 score were 0.731, 1.000, 0.583, and 0.900, respectively. The Clinic–Radscore model had an AUC of 0.994 [95% CI, 0.978–1.000], and the accuracy, sensitivity, specificity, and F1 score values were 0.962, 0.929, 1.000, and 0.931, respectively. In conclusion, the CECT-based radiomics and clinical radiomics ML model exhibited good diagnostic efficacy in differentiating APAs from NAAs; this non-invasive, cost-effective, and efficient method is important for the management of adrenal incidentaloma. [ABSTRACT FROM AUTHOR]

Net primary production (NPP) serves as a crucial indicator of the ecosystem's capacity to capture atmospheric CO2. Gaining insights into the dynamics of NPP and its driving mechanisms is pivotal for optimizing ecosystem carbon sink resource management. Since the implementation of the Grain-for-Green Program (GFGP) in 1999, the Yellow River Basin (YRB) has been one of the most significant areas for ecological restoration in China. However, our knowledge regarding the interannual variability (IAV) of NPP and the underlying driving forces in this region remains incomplete. In this study, we utilized a light use efficiency model to assess the spatiotemporal dynamics, IAV, and driving factors of NPP in the YRB during the period from 1999 to 2018. Our findings revealed that the average annual NPP in the YRB approximated 189.81 Tg C. Over the study duration, NPP significantly increased in 79.63% of the basin with an overall increasing rate of 6.76 g C m−2 yr−1. The most prominent increase was observed in the key GFGP implementation area, predominantly in the semi-humid region. Notably, the middle altitude region (1–1.5 km), semi-humid region, and grassland emerged as the primary contributors to the basin's total vegetation carbon sequestration. However, it is worth emphasizing that there was substantial IAV in the temporal trends of NPP, with the semi-humid region being the most influential contributor (62.66%) to the overall NPP IAV in the YRB. Further analysis of the driving mechanisms unveiled precipitation as the primary driver of NPP IAV in the YRB with a contribution of 62.9%, followed by temperature (23.07%) and radiation (14.03%). Overall, this study deepened our understanding of the IAV and driving mechanisms of NPP in the YRB under ecological restoration, and provided scientific support for optimizing the management of regional carbon sequestration resources. [ABSTRACT FROM AUTHOR]

For a long time, object detection has been a popular but difficult research problem in the field of pattern recognition. In recent years, object detection algorithms based on convolutional neural networks have achieved excellent results. However, neural networks are computationally intensive and parameter redundant, so they are difficult to deploy on resource-limited embedded devices. Especially for two-stage detectors, operations and parameters are mainly clustered on feature fusion of proposals after the region of interest (ROI) pooling layer, and they are enormous. In order to deal with these problems, we propose a subnetwork—efficient feature fusion module (EFFM) to reduce the number of operations and parameters for a two-stage detector. In addition, we propose a multi-scale dilation region proposal network (RPN) to further improve detection accuracy. Finally, our accuracy is higher than Faster RCNN based on VGG16, the number of operations is only half of the latter, and the number of parameters is only one third. [ABSTRACT FROM AUTHOR]

In this paper, novel humidity sensors based on montmorillonite, kaolinite, and composite films coated on micro-cantilevers were prepared to measure the relative humidity (RH) values by the deflection of a micro-cantilever (MC) at room temperature. The humidity-sensing properties, such as response and recovery, sensitivity, repeatability, humidity hysteresis, and long-term stability, were investigated in the range of working humidity (10–80% RH). The humidity response in the close humidity range of 10% RH to 80% RH revealed a linear increase in water absorption of montmorillonite, kaolinite, and montmorillonite/kaolinite mixed dispersant (1:1) as a function of RH with linear correlation factors between the humidity change and deflection estimated to be 0.994, 0.991, and 0.946, respectively. Montmorillonite's sensitivity was better than kaolinite's, with the mixed-clay mineral film's response falling somewhere in between. This research provides a feasible and effective approach to constructing high-performance MC humidity sensors that can be operated at room temperature based on clay minerals. [ABSTRACT FROM AUTHOR]

Glyoxal and methylglyoxal are important volatile organic compounds in the atmosphere. The gas–particle partitioning of these carbonyl compounds makes significant contributions to O3 formation. In this study, both the gas- and particle-phase glyoxal and methylglyoxal concentrations at the foot and top of Mount Hua were determined simultaneously. The results showed that the gaseous-phase glyoxal and methylglyoxal concentrations at the top were higher than those at the foot of the mountain. However, the concentrations for the particle phase showed the opposite trend. The average theoretical values of the gas–particle partitioning coefficients of the glyoxal and methylglyoxal concentrations (4.57 × 10−10 and 9.63 × 10−10 m3 μg−1, respectively) were lower than the observed values (3.79 × 10−3 and 6.79 × 10−3 m3 μg−1, respectively). The effective Henry's law constants (eff.KH) of the glyoxal and methylglyoxal were in the order of 108 to 109 mol/kgH2O/atm, and they were lower at the foot than they were at the top. The particle/gas ratios (P/G ratios) of the glyoxal and methylglyoxal were 0.039 and 0.055, respectively, indicating more glyoxal and methylglyoxal existed in the gas phase. The factors influencing the partitioning coefficients of the glyoxal and methylglyoxal were positively correlated with the relative humidity (RH) and negatively correlated with the PM2.5 value. Moreover, the partitioning coefficient of the glyoxal and methylglyoxal was more significant at the top than at the foot of Mount Hua. [ABSTRACT FROM AUTHOR]

This article introduces a novel framework for diagnosing faults in rolling bearings. The framework combines digital twin data, transfer learning theory, and an enhanced ConvNext deep learning network model. Its purpose is to address the challenges posed by the limited actual fault data density and inadequate result accuracy in existing research on the detection of rolling bearing faults in rotating mechanical equipment. To begin with, the operational rolling bearing is represented in the digital realm through the utilization of a digital twin model. The simulation data produced by this twin model replace traditional experimental data, effectively creating a substantial volume of well-balanced simulated datasets. Next, improvements are made to the ConvNext network by incorporating an unparameterized attention module called the Similarity Attention Module (SimAM) and an efficient channel attention feature referred to as the Efficient Channel Attention Network (ECA). These enhancements serve to augment the network's capability for extracting features. Subsequently, the enhanced network model is trained using the source domain dataset. Simultaneously, the trained model is transferred to the target domain bearing using transfer learning techniques. This transfer learning process enables the accurate fault diagnosis of the main bearing to be achieved. Finally, the proposed method's feasibility is validated, and a comparative analysis is conducted in comparison with similar approaches. The comparative study demonstrates that the proposed method effectively addresses the issue of low mechanical equipment fault data density, leading to improved accuracy in fault detection and classification, along with a certain level of robustness. [ABSTRACT FROM AUTHOR]

Polypropylene (PP)/sepiolite nanocomposites were prepared using the melt blending technique. The effects of nano-sepiolite content on the mechanical property, thermal property, crystallinity, morphology and rheological property of PP/sepiolite nanocomposites were investigated. The organic modified sepiolites (OSep) were dispersed evenly in PP matrix after surface treatment. The addition of OSep improved the storage modulus and thermal stability, showing a strong interaction between OSep and PP matrix. With the increase of OSep content, the fluidity of PP/OSep composites first increased due to the lubrication of surface modifiers and then decreased due to the interaction between OSep and PP. The size of the toughening agent elastomer first increased and then decreased, and the impact notched strength of PP/Osep composites first decreased and then increased. The loading of OSep also reduced the crystallinity and shrinkage rate of PP. PP/OSep nanocomposites have potential applications in high-performance automotive lightweight materials. [ABSTRACT FROM AUTHOR]

Sialyltransferases are key enzymes for the production of sialosides. The versatility of Pasteurella multocida α2,3-sialyltransferase 1 (PmST1) causes difficulties in the efficient synthesis of α2,3-linked sialylatetd compounds, especial its α2,3-sialidase activity. In the current study, the α2,3-sialidase activity of PmST1 was further reduced by rational design-based protein engineering. Three double mutants PMG1 (M144D/R313Y), PMG2 (M144D/R313H) and PMG3 (M144D/R313N) were designed and constructed using M144D as the template and kinetically investigated. In comparison with M144D, the α2,3-sialyltransferase activity of PMG2 was enhanced by 1.4-fold, while its α2,3-sialidase activity was reduced by 4-fold. Two PMG2-based triple mutants PMG2-1 (M144D/R313H/T265S) and PMG2-2 (M144D/R313H/E271F) were then designed, generated and characterized. Compared with PMG2, triple mutants showed slightly improved α2,3-sialyltransferase activity, but their α2,3-sialidase activities were increased by 2.1–2.9 fold. In summary, PMG2 was used for preparative-scale production of 3′-SL (3′-sialyllactose) with a yield of >95%. These new PmST1 mutants could be potentially utilized for efficient synthesis of α2,3-linked sialosides. This work provides a guide to designing and constructing efficient sialyltransferases. [ABSTRACT FROM AUTHOR]

In recent years, three PARP inhibitors and three CDK4/6 inhibitors have been approved by the FDA for the treatment of recurrent ovarian cancer and advanced ER-positive breast cancer, respectively. However, the clinical benefits of the PARPi or CDK4/6i monotherapy are not as satisfied as expected and benefit only a fraction of patients. Current studies have shown therapeutic synergy for combinations of PARPi and CDK4/6i in breast and ovarian cancers with homologous recombination (HR) proficiency, which represents a new synthetic lethal strategy for treatment of these cancers regardless HR status. Thus, any compounds or strategies that can combine PARP and CDK4/6 inhibition will likely have great potential in improving clinic outcomes and in benefiting more patients. In this study, we developed a novel compound, ZC-22, that effectively inhibited both PARP and CDK4/6. This dual-targeting compound significantly inhibited breast and ovarian cancer cells by inducing cell cycle arrest and severe DNA damage both in vitro and in vivo. Interestingly, the efficacy of ZC-22 is even higher than the combination of PARPi Olaparib and CDK4/6i Abemaciclib in most breast and ovarian cancer cells, suggesting that it may be an effective alternative for the PARPi and CDK4/6i combination therapy. Moreover, ZC-22 sensitized breast and ovarian cancer cells to cisplatin treatment, a widely used chemotherapeutic agent. Altogether, our study has demonstrated the potency of a novel CDK4/6 and PARP dual inhibitor, which can potentially be developed into a monotherapy or combinatorial therapy with cisplatin for breast and ovarian cancer patients with HR proficiency. [ABSTRACT FROM AUTHOR]

In this study, the characteristics and formation mechanism of summertime isoprene, monoterpene, and toluene-derived secondary organic aerosols (SOAs) were investigated in a rural area of Guanzhong Plain, Northwest China. The variations in key indicators of primary sources indicated a significant influence of biomass burning on PM2.5 during the observation period. The concentrations of total measured SOA tracers from isoprene, monoterpene, and toluene were 40.85 ± 17.31, 24.27 ± 7.50, and 10.61 ± 0.33 ng/m3, respectively. The average ratio of cis-pinonic and pinic acids to 3-Methyl-1,2,3-butanetricarboxylic acid (MBTCA)(P/M) were 0.45 and 0.85 by day and by night, respectively. The low ratio in the daytime was mainly due to the stronger photo-degradation and particle-to-gas distribution of semi-volatile cis-pinonic and pinic acids. The monoterpene SOA tracers were significantly correlated with levoglucosan at night (R2 = 0.51, p < 0.01), as were toluene SOA tracers and levoglucosan (R2 > 0.67, p < 0.01), indicating the significant contribution of biomass combustion to these SOAs. The mass concentration of isoprene-, monoterpenes-, and toluene-derived SOC was estimated by using the tracer yield method. The total calculated SOCs by day and by night were 0.25–0.71 (average: 0.46) and 0.26–0.78 (average: 0.42) µgC/m3, accounting for 3.35–10.58% and 3.87–13.51% of OC by day and by night, respectively. [ABSTRACT FROM AUTHOR]

K-promoted Mo-based catalysts showed great promise for the hydrogenation of CS2 to methyl mercaptan (CH3SH). However, the research on the synergistic effect of K and Mo, and the active site of CS2 hydrogenation to CH3SH were unexplored widely. To solve this problem, the synergistic effect of K and Mo in the K-promoted Mo-based catalysts for CS2 hydrogenation to prepare CH3SH was investigated. The mesoporous alumina was the support and loaded the active components potassium and molybdenum to prepare the catalyst. The results suggested that the active components K and Mo can not only cooperatively regulate the acid-base sites on the catalyst surface, but also stabilize the molybdate species at +5 valence during the reduction process and increase the Mo unsaturated coordination sites. Combined with the results of the catalytic activity evaluation, indicating that the main active site of the catalysts is the weak Lewis acid-base site, and the strong acidic site and strong alkaline site are not conducive to the formation of CH3SH. Moreover, the possible catalytic mechanism of CS2 hydrogenation to CH3SH on the weak Lewis acid-base sites of the catalysts was proposed. The research results of this paper can provide an experimental basis and theoretical guidance for the design of high-performance CH3SH synthesis catalyst and further mechanism research. [ABSTRACT FROM AUTHOR]

The relationships between initial microstructures, process parameters, and grain evolutions in isothermal holdings have drawn wide attention in recent years, but the grain growth behaviors of 300M steel were not well understood, resulting in a failure in precise microstructure controlling in heat treatment. In this work, in situ observations were carried out to characterize the grain evolutions of 300M steel with varying holding time, holding temperatures, and initial microstructures. The intriguing finding was that the grain refinement by austenization of 300M steel was followed by a dramatic grain growth in the initial stage of holding (≤~600 s), and with increasing time (~600–7200 s), the average grain size appeared to have a limit value at specific temperatures. The austenization process accelerated the grain growth by generating large quantity of grain boundaries at the initial stage of holdings, and the growth rate gradually slowed down after holding for ~600 s because the driven force was weakened due to the reduction of grain boundary energy. The initial structure and the initial grain size of 300M steel had no obvious influences on the grain size evolutions. The mechanisms of grain growth were analyzed based on in situ observations and transmission electron microscope (TEM) characterizations. A grain evolution model considering the grain boundary migration of 300M steel was established for the isothermal holding process. Good agreement was obtained between the in situ observation results and the model calculation results. This investigation aimed to understand fundamentally the grain evolutions of 300M steel in the isothermal holding process. [ABSTRACT FROM AUTHOR]

Amino acid transporters play an important role in cell growth and metabolism. MeAIB, a transporter-selective substrate, often represses the adaptive regulation of sodium-coupled neutral amino acid transporter 2 (SNAT2), which may act as a receptor and regulate cellular amino acid contents, therefore modulating cellular downstream signaling. The aim of this study was to investigate the effects of MeAIB to SNAT2 on cell proliferation, protein turnover, and the mammalian target of rapamycin (mTOR) signaling pathway in porcine enterocytes. Intestinal porcine epithelial cells (IPEC)-J2 cells were cultured in a high-glucose Dulbecco's modified Eagle's (DMEM-H) medium with 0 or 5 mmoL/L System A amino acid analogue (MeAIB) for 48 h. Cells were collected for analysis of proliferation, cell cycle, protein synthesis and degradation, intracellular free amino acids, and the expression of key genes involved in the mTOR signaling pathway. The results showed that SNAT2 inhibition by MeAIB depleted intracellular concentrations of not only SNAT2 amino acid substrates but also of indispensable amino acids (methionine and leucine), and suppressed cell proliferation and impaired protein synthesis. MeAIB inhibited mTOR phosphorylation, which might be involved in three translation regulators, EIF4EBP1, IGFBP3, and DDIT4 from PCR array analysis of the 84 genes related to the mTOR signaling pathway. These results suggest that SNAT2 inhibition treated with MeAIB plays an important role in regulating protein synthesis and mTOR signaling, and provide some information to further clarify its roles in the absorption of amino acids and signal transduction in the porcine small intestine. [ABSTRACT FROM AUTHOR]

To address the demand for natural fibers, developing new varieties that are resistant to abiotic stress is necessary. The present study was designed to investigate the physiological and biochemical traits of three varieties of C. capularis (Y49, Y38, and Y1) and four varieties C. olitorius (T8, W57, M33, M18) under low temperature to identify the cold-tolerant varieties and elucidate the mechanisms involved in enhancing cold tolerance. Research findings revealed that the varieties Y49 and M33 exhibited the highest chlorophyll and carotenoid content. Biochemical profiles revealed that varieties Y49 and M33 were found to be able to withstand low-temperature stress by accumulating different enzymatic and non-enzymatic antioxidants, such as superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), ascorbate peroxidase (APx), glutathione (GSH), and phenolics, which participated in reducing the content of malondialdehyde (MDA) and hydrogen peroxide (H2O2) caused by low temperature. Osmolytes compounds, such as total soluble sugar, significantly increased in Y49 and M33; and proline content decreased in all varieties except Y49 and M33 after low-temperature exposure. The rise in these osmolytes molecules can be a defense mechanism for the jute's osmotic readjustment to reduce the oxidative damage induced by low temperature. Furthermore, PCA and hierarchical cluster analysis distinguished the seven varieties into three separate groups. Results confirmed that group I (Y49 and M33 varieties) were low-temperature tolerant, group II (M18, W57) were intermediate, whereas III groups (Y38, T8, and Y1) were low temperature susceptible. PCA also explained 88.36% of the variance of raw data and clearly distinguished three groups that are similar to the cluster heat map. The study thus confirmed the tolerance of selected varieties that might be an efficient adaptation strategy and utilized them for establishing breeding programs for cold tolerance. [ABSTRACT FROM AUTHOR]

For the dissection and identification of the molecular response mechanisms to salt stress in cannabis, an experiment was conducted surveying the diversity of physiological characteristics. RNA-seq profiling was carried out to identify differential expression genes and pathway which respond to salt stress in different cannabis materials. The result of physiological diversity analyses showed that it is more sensitive to proline contents in K94 than in W20; 6 h was needed to reach the maximum in K94, compared to 12 h in W20. For profiling 0–72 h after treatment, a total of 10,149 differentially expressed genes were identified, and 249 genes exhibited significantly diverse expression levels in K94, which were clustered in plant hormone signal transduction and the MAPK signaling pathway. A total of 371 genes showed significant diversity expression variations in W20, which were clustered in the phenylpropanoid biosynthesis and plant hormone signal transduction pathway. The pathway enrichment by genes which were identified in K94 and W20 showed a similar trend to those clustered in plant hormone signal transduction pathways and MAPK signaling. Otherwise, there were 85 genes which identified overlaps between the two materials, indicating that these may be underlying genes related to salt stress in cannabis. The 86.67% agreement of the RNA-seq and qRT-PCR indicated the accuracy and reliability of the RNA-seq technique. Additionally, the result of physiological diversity was consistent with the predicted RNA-seq-based findings. This research may offer new insights into the molecular networks mediating cannabis to respond to salt stress. [ABSTRACT FROM AUTHOR]

In the current study, the photooxidation reaction of toluene (C7H8) was investigated in a Potential Aerosol Mass Oxidation Flow Reactor (PAM OFR). The hydroxyl radical (OH) exposure of toluene in the PAM OFR ranged from 0.4 to 1.4 × 1012 molec cm−3 s, which is equivalent to 3 to 12 days of atmospheric oxidation. A proton transfer reaction-mass spectrometer (PTR-MS) and a scanning mobility particle sizer (SMPS) were used to study the gas-phase products formed and particle number changes of the oxidation reaction in PAM OFR. The secondary organic aerosol (SOA) formed in the PAM OFR was also collected for off-line chemical analysis. Key gas-phase reaction products of toluene, including glyoxal, methyl glyoxal, unsaturated carbonyl compounds, and benzaldehyde, were identified by the PTR-MS. Second generation products, including acetic acid, formaldehyde, formic acid, and acetaldehyde, were also detected. By comparing the mass spectrums obtained under different OH exposures and relative humidity (RH), changes in the two parameters have minimal effects on the composition of gas-phase products formed, expect for the spectrum obtained at OH exposure of 0.4 × 1012 cm−3 s and RH = 17%, which is slightly different from other spectrums. SMPS results showed that particle mass concentration increases with increasing OH exposure, while particle number concentration first increases and then decreases with increasing OH exposure. This result probably suggests the formation of oligomers at high OH exposure conditions. Off-line chemical analysis of the SOA sample was dominated by C4 diacids, including malic acid, citramalic acid, and tartaric acid. The well-known toluene SOA marker 2,3-Dihydroxy-4-oxopentanoic acid, as well as 2,3-dihydroxyglutaric acid, which has not been identified in previous toluene photooxidation experiments, were also detected in the SOA sample. Our results showed good agreements with the results of previous smog chamber studies of toluene photooxidation reaction, and they suggested that using PAM OFR for studies of oxidation reaction of different VOCs can be atmospherically relevant. [ABSTRACT FROM AUTHOR]

Oxidative stress is involved in a wide variety of pathologies, and fullerene has been shown to have an antioxidant ability. Mycotoxins exert toxic effects through induction of excessive reactive oxygen species (ROS). Here, we evaluated water-soluble fullerene C60 for its anti-mycotoxin and antioxidant effects in vitro and in vivo. Intestinal epithelial cells were cultured with fullerene during deoxynivalenol (DON) exposure. The results revealed that fullerene C60 significantly promoted cell viability, decreased apoptosis and necrotic cell number, and significantly reduced intracellular ROS levels during DON exposure (p < 0.05). To investigate the role of fullerene in antioxidant capacity in vivo further, 40 three-week-old male C57BL/6 mice were randomly divided into four groups. There were no significant differences between the control and fullerene groups (p > 0.05). In mice exposed to DON, supplementation with fullerene C60 significantly improved growth performance, and enhanced the total antioxidant status and the activities of SOD and GPX in the intestine and liver (p < 0.05). In addition, fullerene C60 supplementation improved intestinal morphology, as indicated by a higher villus height and tight junction protein expression (p < 0.05). Furthermore, fullerene supplementation decreased serum concentrations of inflammatory cytokine and lipopolysaccharide (LPS; a penetrability marker) compared to the DON-challenged group (p < 0.05). The current study suggests that fullerene C60 improves intestinal antioxidant status against DON-induced oxidative stress in vitro and in vivo. [ABSTRACT FROM AUTHOR]

Lentiviral vectors (LVs) are a powerful tool for gene and cell therapy and human embryonic kidney cells (HEK293) have been extensively used as a platform for production of these vectors. Like most cells and cellular tissues, HEK293 cells release extracellular vesicles (EVs). EVs released by cells share similar size, biophysical characteristics and even a biogenesis pathway with cell-produced enveloped viruses, making it a challenge to efficiently separate EVs from LVs. Thus, EVs co-purified with LVs during downstream processing, are considered "impurities" in the context of gene and cell therapy. A greater understanding of EVs co-purifying with LVs is needed to enable improved downstream processing. To that end, EVs from an inducible lentivirus producing cell line were studied under two conditions: non-induced and induced. EVs were identified in both conditions, with their presence confirmed by transmission electron microscopy and Western blot. EV cargos from each condition were then further characterized by a multi-omic approach. Nineteen proteins were identified by mass spectrometry as potential EV markers to differentiate EVs in LV preparations. Lipid composition of EV preparations before and after LV induction showed similar enrichment in phosphatidylserine. RNA cargos in EVs showed enrichment in transcripts involved in viral processes and binding functions. These findings provide insights on the product profile of lentiviral preparations and could support the development of improved separation strategies aimed at removing co-produced EVs. [ABSTRACT FROM AUTHOR]

Two single track multi-layer walls with linear energy inputs (LEIs) of 219 and 590 J/mm were deposited by cold metal transfer-based wire arc additive manufacturing system. Combined with the X-ray diffraction technique, scanning electron microscope and uniaxial tensile tests, the influences of LEI and cooling rate (CR) on the microstructure evolution, mechanical properties and fracture mechanisms of the studied steel are analyzed. It is observed that the microstructures of the studied steel are mainly composed of δ-ferrite and austenite dendrites. σ phase is formed on the δferrite–austenite interface under low CR. Meanwhile, the primary dendrites' spacing decreases with the decrease in LEI or the increase in CR, and the maximal primary dendrites' spacing is 32 μm. The values of elongation to fracture roughly decline with the decrease in LEI or the increase in CR, but the variations of ultimate tensile strength and yield stress show an opposite trend. In addition, the mesoscopic damages in the studied steel under low LEI are mainly caused by the coalescence of pores. While under high LEI, the cracks are induced by the dislocations piling up around δ-ferrite. [ABSTRACT FROM AUTHOR]

In this study, we report a novel high-throughput and instant-mixing droplet microfluidic system that can prepare uniformly mixed monodisperse droplets at a flow rate of mL/min designed for rapid mixing between multiple solutions and the preparation of micro-/nanoparticles. The system is composed of a magneton micromixer and a T-junction microfluidic device. The magneton micromixer rapidly mixes multiple solutions uniformly through the rotation of the magneton, and the mixed solution is sheared into monodisperse droplets by the silicone oil in the T-junction microfluidic device. The optimal conditions of the preparation of monodisperse droplets for the system have been found and factors affecting droplet size are analyzed for correlation; for example, the structure of the T-junction microfluidic device, the rotation speed of the magneton, etc. At the same time, through the uniformity of the color of the mixed solution, the mixing performance of the system is quantitatively evaluated. Compared with mainstream micromixers on the market, the system has the best mixing performance. Finally, we used the system to simulate the internal gelation broth preparation of zirconium broth and uranium broth. The results show that the system is expected to realize the preparation of ceramic microspheres at room temperature without cooling by the internal gelation process. [ABSTRACT FROM AUTHOR]

The accelerated global warming and heterogeneous change in precipitation have been resulting in climate system shifts, which plays a key role in the stability of ecosystem and social economic development. Central Asia is account 80% of the temperate desert, characterized by fragile ecosystem; however, it has experienced the fastest warming in recent decades and projected warming in future. The Köppen-Geiger climate classification is a useful tool to assess the potential impacts of climate change on regional ecosystem. The spatial shift and temporal evolution of each climatic zone based on Köppen-Geiger climate classification are analyzed in historical and future period under different scenarios (RCP2.6, RCP4.5 and RCP8.5), high risk regions that might experience more frequent climatic zone shifts are delimited in this study, which could provide the useful information for developing mitigate strategies in coping with the warming threat. The hotter and dryer subtypes of arid climatic zone and warmer subtypes of temperate climatic zone expanded their coverage in Central Asia, corresponding to the tundra climatic, cooler subtype of arid and temperate climatic zone contracted. Based on a method defining the climate-sensitivity, high risk regions are mainly distributed in northern Kazakhstan and Tianshan Mountains region. [ABSTRACT FROM AUTHOR]

Simple Summary: Insect powders, including Tenebrio molitor (TM), Musca domestica larvae (MDL) and Zophobas morio (ZM), as high-quality and renewable protein sources are commonly applied in livestock and poultry feed production. The molecular effect of insect protein on amino acid metabolism in pigs needs to be explored. We found that insect powder as a protein source in feed regulated the mTOR signal pathway and improved amino acid transportation in the intestine for growth promotion. Insect powder may be a potentially promising protein source for pig production. This study was conducted to evaluate the effects of dietary insect powder supplementation as a protein source on plasma amino acid profiles, intestinal amino acid transport and sensing in a piglet model. A total of 144 weanling piglets were randomly assigned to four experimental diets for two phases (Days 1–28 and Days 29–56), to assess the effects on amino acid profiles and transportation in the segments of the intestine. The groups were basal diet (control), control diet plus Tenebrio molitor (TM), control diet plus Musca domestica larvae (MDL) and control diet plus Zophobas morio (ZM). The plasma free amino acid levels were stable comparable among treatments, except that the lysine level was significantly reduced by dietary MDL and ZM supplementation in the first phase (p < 0.05). In the 1st phase, the sensitivity of intestinal segments to the regulation of the amino acid level by insect powder supplementation follows sequence: colon > ileum > jejunum, while the order switched to jejunum > colon > ileum in the 2nd phase. The relative RNA expressions of mitogen-activated protein 4 kinase 3 (MAP4K3), sodium dependent neutral amino acid transporter2 (SNAT2), the transient receptor potential cation channel subfamily V member 1 (TRPV1) and taste 1 receptor member 1/3 (T1R3) in the segments of the intestine were affected by different dietary insect powder supplementation. G protein-coupled receptor family C group 6 member A (GPRC6A) level in the jejunal and colonic mucosa was upregulated by MDL supplementation (p < 0.05). These results indicated that dietary insects improved the metabolism of the amino acid in the prophase (the 1st phase) through regulating the sensing gene and mTOR signal pathway in intestinal mucosa by targeting different receptors. The finding demonstrates that the insect powder is a potentially promising source for protein deposition. [ABSTRACT FROM AUTHOR]

Acetone is a biomarker in the exhaled breath of diabetic patients; sensitive and selective detection of acetone in human exhaled breath plays an important role in noninvasive diagnosis. Tungsten oxide (especially for γ-WO3) is a promising material for the detection of breath acetone. It is generally believed that the stable metastable phase of WO3 (ε-WO3) is the main reason for the improved response to acetone detection. In this work, pure and Cr-doped urchin-like WO3 hollow spheres were synthesized by a facile hydrothermal approach. Analyses of the resulting materials via X-ray photoelectron spectroscopy (XPS) and Raman confirmed that they are mainly composed by γ-WO3. The gas sensing performances of pure and Cr-doped WO3 to acetone were systematically tested. Results show that the sensor based on pure WO3 annealed at 450 °C has a high response of 20.32 toward 100 ppm acetone at a working temperature of 250 °C. After doped with Cr, the response was increased 3.5 times higher than the pure WO3 sensor. The pure and Cr-doped WO3 sensors both exhibit a tiny response to other gases, low detection limits (ppb-level) and an excellent repeatability. The improvement of gas sensing properties could be attributed to an optimized morphology of Cr-doped WO3 by regulating the crystal growth and reducing the assembled nanowires' diameter. The increasing number of oxygen vacancy and the introduction of impurity energy level with trap effect after Cr doping would lead to the wider depletion layer as well as a better gas sensing performance. This work will contribute to the development of new WO3 acetone sensors with a novel morphology and will explain the increased response after Cr doping from a new perspective. [ABSTRACT FROM AUTHOR]

We propose a space benchmark sensor with onboard SI (Système International) traceability by means of quantum optical radiometry. Correlated photon pairs generated by spontaneous parametric down-conversion (SPDC) in nonlinear crystals are used to calibrate the absolute responsivity of a solar observing radiometer. The calibration is systematic, insensitive to degradation and independent of external radiometric standards. Solar spectral irradiance at 380–2500 nm is traceable to the photon rate and Planck's constant with an expected uncertainty of about 0.35%. The principle of SPDC calibration and a prototype design of the solar radiometer are introduced. The uncertainty budget is analyzed in consideration of errors arising from calibration and observation modes. [ABSTRACT FROM AUTHOR]

Simple Summary: Weaning is one of the biggest challenges in a pig's life. Autophagy is a catabolic process aimed at recycling cellular components and damaged organelles in response to diverse stress conditions. There are two autophagy-modifying agents, rapamycin (RAPA) and chloroquine (CQ), that are often used in vitro and in vivo to regulate this process. We speculated that the regulation of autophagy may have some effect on weaning pressure. In this study, we try to understand the role of autophagy in intestinal barrier function and inflammation during the first week after weaning. We examined the effects of modulation of autophagy via RAPA and CQ on growth performance, immunity, inflammation profile, and the intestinal barrier to find potential value for CQ as a feed additive agent for ameliorating weaning stress. Early weaning stress impairs the development of gastrointestinal barrier function, causing immune system dysfunctions, reduction in feed intake, and growth retardation. Autophagy was hypothesized to be a key underlying cellular process in these dysfunctions. We conjectured that rapamycin (RAPA) and chloroquine (CQ), as two autophagy-modifying agents, regulate the autophagy process and may produce deleterious or beneficial effects on intestinal health and growth. To explore the effect of autophagy on early weaning stress in piglets, 18 early-weaned piglets were assigned to three treatments (each treatment of six piglets) and treated with an equal volume of RAPA, CQ, or saline. The degree of autophagy and serum concentrations of immunoglobulins and cytokines, as well as intestinal morphology and tight junction protein expression, were evaluated. Compared with the control treatment, RAPA-treated piglets exhibited activated autophagy and had decreased final body weight (BW) and average daily gain (ADG) (p < 0.05), impaired intestinal morphology and tight junction function, and higher inflammatory responses. The CQ-treated piglets showed higher final BW, ADG, jejuna and ileal villus height, and lower autophagy and inflammation, compared with control piglets (p < 0.05). Throughout the experiment, CQ treatment was beneficial to alleviate early weaning stress and intestinal and immune system dysfunction. [ABSTRACT FROM AUTHOR]

An AC electrified railway can interfere significantly with parallel underground pipelines in a public transportation corridor. Such interference may threaten the long-term transportation and the operational safety of the pipelines. Therefore, this paper presents a mathematical model to illustrate the electromagnetic coupling between an AC electrified railway and nearby parallel underground pipelines. As the basis of the engineering calculation, an integration simulation model based on CDEGS software, which included an electrified railway and pipeline system, was built and its correctness was validated by comparing it with a mathematical model. Also, the effects of electric traction load parameters, pipeline parameters, and soil structure parameters were analyzed, the results of which demonstrate the distribution characteristics of AC interference on parallel underground pipelines. Using a real case in China as an example, protection measures were introduced to decrease coupling interference and their effectiveness was verified by simulation calculations and field measurements. [ABSTRACT FROM AUTHOR]

In the process of electromagnetic forming (EMF), the rebound effect caused by high speed collision between sheet and die will affect the fittability, which results in a bad forming quality of workpiece. In this paper, finite element models of direct EMF and indirect EMF with an elastic medium are established, the influence factors of fittability in indirect EMF are studied, the two forming processes are compared, and the mechanisms of reduced rebound effect in indirect EMF are revealed. The results show that: in indirect EMF, with the increase of the discharging voltage or thickness of rubber, the fittability increases and then decreases; when the thickness of driver plate is equal to the skin depth of the driver plate, the fittability is the best. The optimal process parameters of indirect EMF are as follows: the discharging voltage is 10 kV, the thickness of the rubber is 20 mm and the thickness of driver plate is 2 mm. The rebound effect in indirect EMF is reduced compared with direct EMF for the following reasons: the impact force caused by the collision between the sheet and die is balanced by the pressure provided by the rubber; the sheet is always under tensile stress state due to the friction force provided by rubber; the remaining kinetic energy of sheet after collision with the die is absorbed by rubber. Therefore, the rebound effect in indirect EMF is suppressed compared with direct EMF. So, the fittability of the workpiece is improved, which results in a better forming quality. [ABSTRACT FROM AUTHOR]

The relationship between microstructure and flow behaviour has attracted attention from many researchers for the past decades, whilst the influences of dislocation and recrystallization on flow stress have not been well understood, which led to failure in flow stress prediction at high temperature compressions. In this work, we tried to provide a novel explanation of the relationship between microstructure evolutions and flow behaviour, and the influence of dislocation and recrystallization on flow stress was investigated. A dislocation based flow stress model was proposed and applied for 300M steel at the strain rate of 0.01–10 s−1 and the temperature of 950–1150 °C. Results showed the established model could predict the flow stress both at constant strain rate conditions and at variable strain rate conditions. The present investigation is helpful to a better understanding of hardening and softening mechanisms in hot compression of 300M steel. [ABSTRACT FROM AUTHOR]