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As a classic problem of high-resolution remote sensing image tasks, land cover classification has many challenges, for instance, variable scales and low-edge discrimination. Traditional spatial semantic segmentation methods based on single-scale feature extraction are challenging to model multi-scale features. They cannot effectively fit high-resolution remote sensing images with variable scales and are prone to misclassification issues. On the other hand, spatial multi-scale semantic segmentation methods lack edge constraints, which can easily lead to edge segmentation ambiguity issues. We propose a segmentation network based on a multi-scale frequency-domain attention gating mechanism (MFAGNet) to solve the above problems. Specifically, we obtain multi-scale features through multi-scale input and design the discrete cosine transform channel attention module (DCTCAM). In DCTCAM, we extract global low-frequency features and effectively alleviate misclassification caused by scale changes. The edge features of the image are obtained through the high-frequency feature extraction module (HFEM) by using edge detection operators to enhance the model's ability to recognize edges. Additionally, no further pooling operations are employed except for a single max pooling layer in the backbone network. In this paper, we design a new gating mechanism to dynamically control the extraction ratio of various frequency features so that it can adapt to input images of different scales. This paper conducts comparative experiments on three high-resolution land cover datasets: GID, Vaihingen, and Potsdam. The new algorithm proposed compares with classic semantic segmentation models such as DANet, PSPNet, SegNet, UNet, DeepLabv3+, FcaNet, BiSeNet, AFN, and FastFCN. The experimental results show that MFAGNet is superior to the comparison models. With no significant increase in computing overhead, MFAGNet obtains MIoU of 69.05%, 73.40%, and 79.42% on the standard data sets GID, Vaihingen, and Potsdam, respectively. [ABSTRACT FROM AUTHOR]

The use of magnetic carbon nanotubes for multi-modal cancer treatment, incorporating both hyperthermia and drug delivery functions, has drawn substantial interest. Yet, the present method of regulating hyperthermia temperature involves manually adjusting the magnetic field intensity, adding to the complexity and difficulty of clinical applications. This study seeks to design novel magnetic carbon nanotubes capable of self-temperature regulation, and investigate their drug loading and release characteristics. Using the co-precipitation method, we synthesized magnetic carbon nanotubes with a Curie temperature of 43 °C. A comprehensive investigation was conducted to analyze their morphology, crystal structure, and magnetic characteristics. To enhance their functionality, chitosan and sodium alginate modifications were introduced, enabling the loading of the antitumor drug doxorubicin hydrochloride (DOX) into these magnetic carbon nanotubes. Subsequently, the loading and release properties of DOX were investigated within the modified magnetic nanotubes. Under alternating magnetic field, magnetic carbon nanotubes exhibit self-regulating properties by undergoing a magnetic phase transition, maintaining temperatures around 43 °C as required for hyperthermia. On the other hand, during magnetic induction heating, the release percentage of DOX reached 23.5% within 2 h and 71.7% within 70 h at tumor pH conditions, indicating their potential for sustained drug release. The prepared magnetic carbon nanotubes can effectively regulate the temperature during hyperthermia treatment while ensuring controlled drug release, which presents a promising method for preparing nanomaterials that synergistically enhance magnetic hyperthermia and chemotherapy drugs. [ABSTRACT FROM AUTHOR]

Rapid analysis of pharmaceutical preparations is of great interest in clinical studies with benefits for identifying counterfeit drugs. In this study, droplet spray ionization tandem mass spectrometry (DSI-MS/MS) was developed for the rapid determination of adenine arabinoside monophosphate in pharmaceutical injections without complex sample pretreatment. The sample solution was loaded on the slip corner placed in front of the inlet of a mass spectrometer, and high voltage was applied to the solution to create a charged spray from the corner for MS analysis. The sample was loaded for analysis without additional sample preparation protocols, which greatly simplifies the operation. The limit of detection and limit of quantification were determined to be 2.7 and 9.1 ng/mL, respectively. The recoveries were in the range from 96% to 112%, and the calculated relative standard deviations were less than 7% for the DSI-MS/MS method. Three adenine arabinoside monophosphate pharmaceutical injection samples and a degraded sample obtained by acid treatment at 40 °C were successfully analyzed by directly dissolving and diluting the sample. Moreover, the sample-loading step required only 2 s. Together these capabilities indicate that the DSI-MS/MS is a simple and robust method and has promising applications in pharmacology studies without complicated sample pretreatment. [ABSTRACT FROM AUTHOR]

Based on the acceleration data measured by penetration experiments with ogive-nose projectiles into semi-infinite concrete targets, a fuzzy method which can calculate the real-time penetration depth was developed. In the proposed method, the whole process of penetration was divided into three stages according to the instantaneous velocity, and each stage was described by different models. By judging the calculation error, threshold velocities between stages were automatically determined. Meanwhile, the striking velocity of the penetration process was calculated using the acceleration in whole trajectory. The calculated values by model are in reasonably good agreement with the measured data from experiments. [ABSTRACT FROM AUTHOR]

The styrene-butadiene-styrene copolymer (SBS)–modified asphalt was aged by pressure aging vessel test. The effect of different content of rejuvenators on the physical and rheological properties of aged SBS-modified asphalt was investigated. The results showed that with the increase of the content, the physical and rheological properties of the aged SBS-modified asphalt are restored more significantly. Three kinds of rejuvenators were used to rejuvenate the properties of aged SBS-modified asphalt. It can be concluded that the improvement of rejuvenator-III on the properties of aged SBS-modified asphalt is the most obvious. The results also indicate that the rheological behavior of the aged SBS-modified asphalt is improved obviously by the rejuvenator. [ABSTRACT FROM AUTHOR]

Problem-solving has been one of the major strands in science education research. But much of the problem-solving research has been conducted on discipline-based contexts; little research has been done on how students, especially individuals, solve interdisciplinary problems. To understand how individuals reason about interdisciplinary problems, we conducted an interview study with 16 graduate students coming from a variety of disciplinary backgrounds. During the interviews, we asked participants to solve two interdisciplinary science problems on the topic of osmosis. We investigated participants’ problem reasoning processes and probed in their attitudes toward general interdisciplinary approach and specific interdisciplinary problems. Through a careful inductive content analysis of their responses, we studied how disciplinary, cognitive, and affective factors influenced their interdisciplinary problems-solving. We found that participants’ prior discipline-based science learning experiences had both positive and negative influences on their interdisciplinary problem-solving. These influences were embodied in their conceptualization of the interdisciplinary problems, the strategies they used to integrate different disciplinary knowledge, and the attitudes they had toward interdisciplinary approach in general and specific interdisciplinary problems. This study sheds light on interdisciplinary science education by revealing the complex relationship between disciplinary learning and interdisciplinary problem-solving. [ABSTRACT FROM PUBLISHER]

This article deals with the problem of mean square stability of discrete-time networked control systems (NCSs) over a communication channel subject to packet dropout. By introducing a parameter-independent slack variable with lower triangular structure, the existence of a static output feedback controller is formulated in the form of linear matrix inequalities. Neither equality constraint nor iterative algorithm is involved through the derivation of the controller. Furthermore, a new algorithm is proposed to obtain the admissible packet dropout probability bound for the given controller gain. This is particularly important in the co-design of controller and scheduling for NCSs. The simplicity of the methods is demonstrated by numerical examples. [ABSTRACT FROM AUTHOR]

A two-year field experiment was conducted to determine the effects of removal of early-fruiting branches (REFB) on yield, quality, and endotoxin expression in transgenic Bt (Bacillus thuringiensis) cotton (Gossypium hirsutum L.). Two early-fruiting branches of field-grown cotton plants were removed and retained at squaring to form the REFB and the control treatments, respectively. Lint yield, yield components, fibre quality, and Cry1Ac protein concentration in the first fully expanded young leaves on the main stem were measured. Results show that lint yields were increased by 5.1 and 5.5% with REFB compared with control in 2004 and 2005, respectively. There was no difference in fibre quality in the first two harvests between REFB and control, but fibre strength and micronarie in the third harvest were improved with REFB. Levels of total N, soluble protein, and Cry1Ac protein as well as glutamic-pyruvic transaminase (GPT) activity in leaves were higher in REFB than in the control. Laboratory bioassay showed significant enhancement of the control efficacy by REFB in terms of Helicoverpa armigera (Hubner) neonate mortality for both years. It is suggested that REFB might be a potential practice for enhancing transgenic Bt cotton production. [ABSTRACT FROM AUTHOR]

To promote the transformation of remote sensing (RS) data into geoscience knowledge, it is necessary to provide better data discovery capabilities, especially when large amounts of RS data have been accumulated. Spatio-temporal range query is one of them to enable data discovery on RS images by the spatio-temporal range. Although existing RS image indexing methods are suitable for data discovery based on spatio-temporal range queries, they do not fully consider the problem of low data retrieval efficiency when the temporal and spatial range scales are unbalanced. To address this problem, we propose a multi-scale spatio-temporal grid index model (MSTGI). First, we divide the time dimension into three levels according to the granularity of year, month and day, and build an independent grid index structure for the object at different levels. Second, we design an adaptive hierarchical indexing strategy to perform parallel retrieval in an appropriate combination of partitions. MSTGI linearizes the grid obtained after global geospatial subdivision using Hilbert curves. Our experimental results, obtained on the Landsat series satellite dataset, reveal that the proposed method improves query efficiency levels by approximately 12.582% and 87.754% compared with GeoSOT-ST and AGMC at various spatial scales, respectively, and reaches 100% recall. [ABSTRACT FROM AUTHOR]

Accidental surcharges caused by unauthorized damped waste are the most serious hazard threatening the serviceability and structural safety of shield tunnels in Shanghai, China. It is highly desirable to assess the effect of such accidental surcharges on the performance of shield tunnels. Nevertheless, the occurrence and magnitude of the accidental surcharges are both highly uncertain. In this paper, a probabilistic method is suggested to evaluate the performance of shield tunnels subjected to accidental surcharges, which can systematically consider the uncertainty in the soil properties, the uncertainty in the magnitude of the accidental surcharges, and the uncertainty of the occurrence of the accidental surcharges. The suggested method is used to analyse the potential effect of accidental surcharges on the safety of tunnels in Shanghai. It is found that the maximum height of the surcharges and the mean rate of the surcharges can significantly affect the performance of shield tunnels. Considering the past performance of shield tunnels can increase our confidence in the future performance of the tunnels. The suggested method provides a practical means to quantify the risk posed by the accidental surcharges to the performance of the shield tunnels. [ABSTRACT FROM AUTHOR]

Students need to think and work across disciplinary boundaries in the twenty-first century. However, it is unclear what interdisciplinary thinking means and how to analyze interdisciplinary interactions in teamwork. In this paper, drawing on multiple theoretical perspectives and empirical analysis of discourse contents, we formulate a theoretical framework that helps analyze interdisciplinary reasoning and communication (IRC) processes in interdisciplinary collaboration. Specifically, we propose four interrelated IRC processes—integration,translation,transfer, andtransformation, and develop a corresponding analytic framework. We apply the framework to analyze two meetings of a project that aims to develop interdisciplinary science assessment items. The results illustrate that the framework can help interpret the interdisciplinary meeting dynamics and patterns. Our coding process and results also suggest that these IRC processes can be further examined in terms of interconnected sub-processes. We also discuss the implications of using the framework in conceptualizing, practicing, and researching interdisciplinary learning and teaching in science education. [ABSTRACT FROM PUBLISHER]

Ultraviolet (UV) absorbents have been used in sunscreen products in the cosmetic industry, showing adverse effects like rising skin irritation and huge toxicological risks. Although nanostructured lipid carriers (NLCs) are regarded as the potential delivery systems for increasing the amount of encapsulated sunscreen agents and playing UV synergistic effect, the overall synergistic ability is insufficient to meet the industrial demand. In the current study, we optimized a new type of sunscreen composite carrier formulation, the SiO2-NLC nanocomposites carrying ethyl methoxycinnamate (OMC) (OMC/SiO2-NLC), describing their features and functional performance. The OMC/SiO2-NLC nanocomposites are emerging sunscreen systems for cosmetic applications, which combine the advantages of both SiO2 and NLCs. The OMC/SiO2-NLC products, as compared to the ordinary cosmetic emulsion, were characterized using Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscope, and UV spectrophotometer. In addition, the nanocomposites were also tested for safety and functional properties. The results showed that the OMC/SiO2-NLC particles could effectively encapsulate the sunscreen, in which the encapsulation efficiency reached 76%. The UV absorbance value of the OMC/SiO2-NLC composite carrier containing the same amount of OMC was significantly increased compared with OMC/NLC. The composite carrier's sun protection factor (SPF) increased 56.7%. Photostability of the OMC/SiO2-NLC particles maintained stability for more than 10 hours under UV radiations. The SiO2-based nanocomposites showed better biocompatibility and UV synergistic performance. Therefore, the optimized composite carrier was a suitable nanocomposite for cosmetic applications. [ABSTRACT FROM AUTHOR]

A new method for the determination of trace bisphenol A (BPA) and diethylstilbestrol (DES) in water samples has been developed by using three phase hollow fiber liquid-phase microextraction (HF-LPME) and an ionic liquid (IL, 1-Octyl-3-methylimidazolium hexafluorophosphate, [C8MIM][PF6]) as supported phase (IL-HF-LPME) combined with high performance liquid chromatography/ultraviolet spectrophotometry (HPLC/UV). The optimized microextraction conditions were as follows: [C8MIM][PF6] was used as the extraction solvent, pH 10 NaOH solution, 5 µL, as acceptor phase; 20 mL water sample with NaCl (5%, w/v) as donor phase and the extraction time was 30 min (stirring rate 200 rpm, 25°C). Under the optimal extraction conditions, the proposed method offered: good linearity range, 0.30–100 µg L−1, with correlation coefficients (r2) of 0.9996 and 0.9988; low detection limit, 0.20 and 0.05 µg L−1(S/N = 3) for BPA and DES, respectively; good reproducibility (relative standard deviation, RSD, 7.28% and 8.45%, respectively,n = 5); high enrichment factor, 850 and 624, respectively. The method was used to analyze real water samples, and satisfactory recoveries (75.4–99.2%) were obtained, which confirmed that the developed method was simple and environmentally friendly for the determination of BPA and DES in aquatic systems. Meanwhile, it was found that humic acid had no obvious influence on enrichment factor. [ABSTRACT FROM PUBLISHER]

Air-coupled ultrasonic testing (ACUT) technique has been viewed as a viable solution in defect detection of advanced composites used in aerospace and aviation industries. However, the giant mismatch of acoustic impedance in air–solid interface makes the transmission efficiency of ultrasound low, and leads to poor signal-to-noise (SNR) ratio of received signal. The utilisation of signal-processing techniques in non-destructive testing is highly appreciated. This paper presents a wavelet filtering and phase-coded pulse compression hybrid method to improve the SNR and output power of received signal. The wavelet transform is utilised to filter insignificant components from noisy ultrasonic signal, and pulse compression process is used to improve the power of correlated signal based on cross-correction algorithm. For the purpose of reasonable parameter selection, different families of wavelets (Daubechies, Symlet and Coiflet) and decomposition level in discrete wavelet transform are analysed, different Barker codes (5–13 bits) are also analysed to acquire higher main-to-side lobe ratio. The performance of the hybrid method was verified in a honeycomb composite sample. Experimental results demonstrated that the proposed method is very efficient in improving the SNR and signal strength. The applicability of the proposed method seems to be a very promising tool to evaluate the integrity of high ultrasound attenuation composite materials using the ACUT. [ABSTRACT FROM AUTHOR]

Tetracalcium phosphate (TTCP, Ca4(PO4)2O) was functionalized by poly (l-lactic acid) (PLLA) in order to improve the dispersion of TTCP particles in poly (butylene succinate) (PBS) matrices, and then a series of the PLLA grafted TTCP/PBS (g-TTCP/PBS) composites were prepared via melt processing. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), tensile analysis, differential scanning calorimetry (DSC), thermogravimetric analysis (DTG/TGA) and melt rheological analysis were used to investigate the structure and properties of the g-TTCP/PBS composites. The results revealed that l-lactide could be grafted onto the surface of TTCP, and the g-TTCP/PBS composites showed the best mechanical properties when the content of g-TTCP was 10 wt%. The crystallization temperature of g-TTCP/PBS composites tended to increase with the increase of g-TTCP contents. The functionalized particles played an important role in augmenting the thermal degradation rate and the complex viscosity of the composites due to their unique structure and the reasonable interfacial interaction between the particles and PBS matrix. [ABSTRACT FROM PUBLISHER]

To investigate the structure-activity relationship of L-glutamine and L-asparagine Schiff base copper complexes in applications, L-glutamine and L-asparagine Schiff bases (GV and AV) and their copper complexes [Cu3(GV)2(CH3COO)2(H2O)] · 2H2O (GVC) and [CuAV(H2O)3] (AVC) have been synthesized and characterized by molar conductance, elemental analysis, UV-Vis, IR, 1H-NMR, and TG-DTG. We examined the geometries of GV, AV, GVC, and AVC through Hartree-Fock method and electronic absorption spectra. We also tested their antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Bacillus subtilis bacteria and antiproliferation activity on human breast cancer MDA-MB-231 cells. The side chain difference between L-glutamine and L-asparagine results in different geometry of GV and AV, which leads to different geometry of GVC and AVC. GVC, a trinuclear Cu(II) complex, shows the highest antibacterial activity and the highest growth inhibition activity on MDA-MB-231 cells. Our results suggest that GVC has potential as an antibacterial and anticancer agent. [ABSTRACT FROM AUTHOR]

To investigate whether Foxo3a expression is correlated with p27kip1 protein levels as well as how it might be clinically relevant, we evaluated the expression of Foxo3a in several ovarian tumors. Immunohistochemical analysis was performed in 63 cases of ovarian tumors. Ten cases were evaluated by Western blot analysis. There was a correlation observed between Foxo3a over-expression and clinic pathological parameters (p = 0.032). Kaplan-Meier survival analysis showed that Foxo3a low expression was significantly associated with poor prognosis of patients. It may be a useful prognostic marker and target in ovarian cancer. [ABSTRACT FROM AUTHOR]

A new Schiff base ligand (KH2L) was synthesized using potassium salt of glycine and 2,4-dihydroxybenzaldehyde. A binuclear complex of this ligand [Cu2 (HL)2] 2H2O was synthesized and characterized by elemental analyses, IR, UV, TG-DTG, and molar conductance. The fundamental electrochemical characteristics of the Cu(II) complex have been studied, and the interaction of the copper complex and DNA was also studied by cyclic voltammetry and fluorescence spectra. The results of the cyclic voltammetry showed that the Cu(II) complex had an oxidation peak with the oxidation potential at -0.345 V. After the DNA was added, the peak current declined with the peak potential shifting positively. This suggested that the complex combined with DNA in the form of intercalative binding, which was also proved by the fluorescence analysis. [ABSTRACT FROM AUTHOR]