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Background: The occurrence and progression of breast cancer are closely linked to copper ion homeostasis. Both copper deficiency and excess can inhibit breast cancer growth, while copper transport systems may contribute to its progression by regulating copper ion transport and the activity of associated proteins. However, a comprehensive review of the roles and applications of copper transport systems in breast cancer remains limited. In this study, we summarize the workflow of copper transport systems and the dual role of copper in cancer, highlighting the contributions of specific members of the copper transport system to breast cancer. Methods: A comprehensive search of the PubMed database was conducted to identify articles published over the past 30 years that focus on the relationship between copper transport system members and breast cancer. The findings were synthesized to elucidate the roles and mechanisms of these transporters in the onset and progression of breast cancer. Results: We identified 13 members of the copper transport system associated with the occurrence, progression, and mortality of breast cancer, including SLC31A1, DMT1, ATP7A, ATP7B, MTs, GSH, ATOX1, CCS, COX17, SCO1, SCO2, and COX11. Our findings revealed that, apart from STEAP, the remaining 12 members were overexpressed in breast cancer. These members influence the onset, progression, and cell death of breast cancer by modulating biological pathways such as intracellular copper ion levels and ROS. Notably, we observed for the first time that depletion of the copper storage protein GSH leads to increased copper ion accumulation, resulting in cuproptosis in breast cancer cells. Conclusion: By integrating the members of the copper transport system in breast cancer, we offer novel insights for the treatment of breast cancer and copper‐related therapies. [ABSTRACT FROM AUTHOR]

Introduction: Chemo-immunotherapy based on inducing tumor immunogenic cell death (ICD)with chemotherapy drugs has filled the gaps between traditional chemotherapy and immunotherapy. It is verified that paclitaxel (PTX) can induce breast tumor ICD. From this basis, a kind of nanoparticle that can efficiently deliver different drug components simultaneously is constructed. The purpose of this study is for the sake of exploring the scheme of chemotherapy-induced ICD combined with other immunotherapy to enhance tumor immunogenicity and inhibit the growth, metastasis, and recurrence of breast tumors, so as to provide a research basis for solving the tough problem of breast cancer treatment. Methods: Nanomedicine loaded with PTX, small interference RNA that suppresses CD47 expression (CD47siRNA, siCD47), and immunomodulator R848 were prepared by the double emulsification method. The hydrodynamic diameter and zeta potential of NP/PTX/siCD47/R848 were characterized. Established the tumor-bearing mice model of mouse breast cancer cell line (4T1) in situ and observed the effect of intravenous injection of NP/PTX/siCD47/R848 on the growth of 4T1 tumor in situ. Flow cytometry was used to detect the effect of drugs on tumor immune cells. Results: NP/PTX/siCD47/R848 nano-drug with tumor therapeutic potential were successfully prepared by double emulsification method, with particle size of 121.5 ± 4.5 nm and surface potential of 36.1 ± 2.5 mV. The calreticulin on the surface of cell membrane and extracellular ATP or HMGB1 of 4T1 cells increased through treatment with NPs. NP/PTX-treated tumor cells could cause activation of BMDCs and BMDMs. After intravenous injection, NP/PTX could quickly reach the tumor site and accumulate for 24 h. The weight and volume of tumor in situ in the breast cancer model mice injected with nanomedicine through the tail vein were significantly lower than those in the PBS group. The ratio of CD8+/CD4+ T cells in the tumor microenvironment and the percentage of dendritic cells in peripheral blood increased significantly in breast cancer model mice injected with nano-drugs through the tail vein. Discussion: Briefly, the chemotherapeutic drug paclitaxel can induce breast cancer to induce ICD. The nanomedicine which can deliver PTX, CD47siRNA, and R848 at the same time was prepared by double emulsification. NP/PTX/siCD47/R848 nano-drug can be enriched in the tumor site. The experiment of 4T1 cell tumor-bearing mice shows that the nano-drug can enhance tumor immunogenicity and inhibit breast tumor growth, which provides a new scheme for breast cancer treatment. (Graphical abstract) Intravenous injection of PTX-loaded nanomedicine based on PEG-PLGA causes immunogenic death of tumor cells and simultaneously reduces tumor cell immune escape, promotes macrophage polarization towards MI subtypes, and effectively activates DCs, thereby enhancing anti-tumor immunity. [ABSTRACT FROM AUTHOR]

The feasibility of industrial waste fly ash as an alternative fluxing agent for silica in carbothermal reduction of medium-low-grade phosphate ore was studied in this paper. With a series of single-factor experiments, the reduction rate of phosphate rock under different reaction temperature, reaction time, particle size, carbon excess coefficient, and silicon–calcium molar ratio was investigated with silica and fly ash as fluxing agents. Higher reduction rates were obtained with fly ash fluxing instead of silica. The optimal conditions were derived as: reaction temperature 1,300°C, reaction time 75 min, particle size 48–75 µm, carbon excess coefficient 1.2, and silicon–calcium molar ratio 1.2. The optimized process condition was verified with other two different phosphate rocks and it was proved universally. The apparent kinetics analyses demonstrated that the activation energy of fly ash fluxing is reduced by 31.57 kJ/mol as compared with that of silica. The mechanism of better fluxing effect by fly ash may be ascribed to the fact that the products formed within fly ash increase the amount of liquid phase in the reaction system and promote reduction reaction. Preliminary feasibility about the recycling of industrial waste fly ash in thermal phosphoric acid industry was elucidated in the paper.

The effects of particle size on the apparent kinetics of carbothermal reduction process of phosphate rock were studied by non-isothermal thermogravimetric analyses. Phosphate rock of various particle size was reacted with coke and silica under high purity argon atmosphere. The apparent kinetic model and parameters of carbothermal reduction reaction of phosphate rock with different particle sizes were derived by combination of model-free (Flynn–Wall–Ozawa, Kissinger–Akahira–Sunose, Tang, Starink) and model-fitting (Coats-Redfern, Master-plots) methods. The results showed that the obtained apparent activation energy of reaction reduces from 371.74 kJ/mol to 321.11 kJ/mol as the particle size of phosphate rock decreasing from 100–150 μm to 38–48 μm. The reaction apparent kinetics was found to follow shrinking-core model and the conversion degree function equation is G(α)=1−(1−α)12G\left( \alpha \right) = 1 - {\left( {1 - \alpha } \right)^{{1 \over 2}}} (α is conversion degree and G(α) is integral form of conversion degree function).

Prenatal developmental toxicity research focuses on understanding the potential adverse effects of environmental agents, drugs, and chemicals on the development of embryos and fetuses. Traditional methods involve animal testing, but ethical concerns and the need for human-relevant models have prompted the exploration of alternatives. Pluripotent stem cells (PSCs) are versatile cells with the unique ability to differentiate into any cell type, serving as a foundational tool for studying human development. Two-dimensional (2D) PSC models are often chosen for their ease of use and reproducibility for high-throughput screening. However, they lack the complexity of an in vivo environment. Alternatively, three-dimensional (3D) PSC models, such as organoids, offer tissue architecture and intercellular communication more reminiscent of in vivo conditions. However, they are complicated to produce and analyze, usually requiring advanced and expensive techniques. This review discusses recent advances in the use of human PSCs differentiated into brain and heart lineages and emerging tools and methods that can be combined with PSCs to help address important scientific questions in the area of developmental toxicology. These advancements and new approach methods align with the push for more relevant and predictive developmental toxicity assessment, combining innovative techniques with organoid models to advance regulatory decision-making. [ABSTRACT FROM AUTHOR]

Dopamine (DA) is a crucial neurotransmitter in the central nervous system (CNS) of human and multicellular animal brains. In this paper, we report for the first time the synthesis of carbon black (C)/phosphotungstic acid (PWA) composites by doping PWA on carbon black nanoparticles by impregnation method. The synthesized materials were characterized using high‐resolution scanning electron microscopy (SEM), X‐ray diffraction spectroscopy (XRD) and Fourier transform infrared spectroscopy (FT‐IR). Glassy carbon electrodes (GCE) modified by C/PWA composites were used to detect dopamine. The electrochemical redox behavior of DA was studied with cyclic voltammetry (CV). Under optimized conditions, DA was detected by differential pulse voltammetry (DPV) and the calibration plot showed linearity (R2=0.9988) over the range of DA concentrations of 10 μM‐600 μM with a detection limit of 0.1 μM. The sensor's capability to detect DA in commercial DA injections in real time has been successfully demonstrated. [ABSTRACT FROM AUTHOR]

Recently, the focus of entity linking research has centered on the zero-shot scenario, where the entity purposed to be labeled at the time of testing was never observed during the training phase, or it may belong to a different domain than the source domain. Current studies have used BERT as the base encoder, as it effectively establishes distributional links between source and target domains. The currently available negative sampling methods all use an extractive approach, which makes it difficult for the models to learn diverse and more challenging negative samples. To address this problem, we propose a generative negative sampling method, adaptive_mixup_hard, which generates more difficult negative entities by fusing the features of both positive and negative samples on top of hard negative sampling and introduces a transformable adaptive parameter, W, to increase the diversity of negative samples. Next, we fuse our method with the Biencoder architecture and evaluate its performance under three different score functions. Ultimately, experimental results on the standard benchmark dataset, Zeshel, demonstrate the effectiveness of our method. [ABSTRACT FROM AUTHOR]

As a classical sparse reconstruction algorithm, iterative soft thresholding (IST) is often used in SAR sparse imaging applications. However, for moving targets, the radar echo contains an unknown phase error, so it is difficult to directly apply the IST algorithm to reconstruct the SAR moving target image. In this article, a parametric IST (P-IST) algorithm is proposed for refocusing of moving targets in synthetic aperture radar (SAR) images. In this algorithm, the echo phase error is modeled as a function of the phase compensation factor, and in the iteration process, a phase compensation factor optimization selection step based on residual energy minimization is added. Compared with the existing algorithms, the proposed P-IST algorithm can obtain the global optimal solution and has better efficiency and robustness. Both simulated data and measured data are used to validate the effectiveness of the proposed algorithm. [ABSTRACT FROM AUTHOR]

As a special feature of rotor target, rotational angular velocity can provide important information for target classification and recognition. In this paper, a rotational angular velocity estimation method is proposed based on complex empirical mode decomposition (CEMD) and three-dimensional orthogonal matching pursuit (3D-OMP)-based parametric sparse representation (PSR) technique. Firstly, the translational radial velocity is estimated from radar echo via Fourier transform, and then the translational compensation is implemented according to the estimated velocity. Secondly, in order to eliminate the influence of the target main body echo on micro-Doppler parameter estimation, CEMD algorithm is adopted for target echo separation. Then, the separated signal of rotor echo is formulated as a jointly sparse signal through a three-dimensional parametric dictionary matrix, which converts the rotational angular velocity estimation into a problem of dynamic representation of jointly sparse signals. Finally, in order to reduce the computational complexity of the estimation method, we propose a 3D-OMP-based parametric sparse representation algorithm to achieve the sparse solution, and the rotational angular velocity can be estimated by minimizing the reconstruction error. The experimental results verify the effectiveness of the proposed algorithm. [ABSTRACT FROM AUTHOR]

In space-air-based bistatic early warning radar (SABBEWR) application, the standard Radon–Fourier transform (RFT) can effectively reduce the deterioration of target-detection performance caused by the serious range migration. However, the rounding operation used in RFT will cause the target trajectory error and lead to the loss of the integration energy. To solve this problem, a modified RFT-based target detection algorithm which implements in the range-frequency domain is proposed for SABBEWR. Firstly, the target echo signal model is established, and then the chirp-Z transform is used to complete the range-migration correction and long-term coherent integration in the range-frequency domain. The experimental results demonstrate that the coherent integration performance of the proposed algorithm is superior to that of the standard RFT algorithm, and the proposed algorithm can effectively detect a high-velocity target in a strong clutter background. [ABSTRACT FROM AUTHOR]

A new polysaccharides fraction (PSF) was isolated from the extraction of flue-cured tobacco stem with hot water and purified through ethanol precipitation, deproteinization and Sepharose CL-6B column chromatography. Structural features of PSF were elucidated by a combination of FT-IR and GC-MS. The results revealed that PSF was heteropolysaccharide mainly consisted of mannose, arabinose, galactose and glucose. The molecular characteristics of PSF were examined by a multiangle laser-light scattering (MALLS) and refractive index (RI) detector system. The SEC/MALLS analysis revealed that the PSF had an average molecular weight about 3.142 × 104 g/mol with the low polydispersity (Mw/Mn=1.247). The molecular shape of the PSF was a rigid sphere in the aqueous solution. The results of antioxidant assay showed that the PSF significantly scavenged hydroxyl (OH) and DPPH radical in a concentration-dependent manner. The results reveal that PSF is a useful antioxidant and might be available for relevant industrial application. [ABSTRACT FROM AUTHOR]

The essential oil was isolated using the water steam distillation from the peel of Citrus maxima (Burm.) Merr. cv. Shatian Yu with a yield of 0.31% (w/w). The essential oil sample were analyzed by GC-MS and total sixty six components were identified. The major compounds were found to be identical namely D-limonene (86.4%) and nootkatone (2.11%). The essential oil displayed broad spectrum antibacterial activity against a panel of pathogenic bacteria and was most effective against Bacillus licheniformis. Thus, pummelo essential oil could be a potential antimicrobial agent. [ABSTRACT FROM AUTHOR]

Inspired by the theoretical advances of compressed sensing, lots of sparsity-aware methods have been proposed for squinted synthetic aperture radar (SAR) imaging based on the single-measurement vector (SMV) model. Compared with SMV, the multiple measurement vectors (MMV) model has been demonstrated to have better reconstruction performance. In fact, echo received by SAR at different azimuth positions can be viewed as MMVs. However, the MMV model cannot be directly used in squinted SAR imaging, because MMV requires multiple sparse vectors of the common sparse structures, while the high-resolution range profiles (HRRPs) obtained by squinted SAR at different azimuth positions have different sparse structures due to range migration effect. A squinted SAR imaging method is proposed based on MMV. First, a modified MMV model that considers range migration is built to realize sparse representation of echo. Additionally, an improved orthogonal matching pursuit algorithm is developed to reconstruct HRRPs. Finally, a high-resolution two-dimensional image result can be easily achieved via traditional azimuth match filtering. Experimental results based on both simulated and real data demonstrate that the proposed MMV-based method can provide better computational efficiency and antinoise ability compared to the SMV-based method. [ABSTRACT FROM AUTHOR]

Concerns about the safety of Bisphenol A, a chemical found in plastics, receipts, food packaging and more, have led to its replacement with substitutes now found in a multitude of consumer products. However, several popular BPA-free alternatives, such as Bisphenol S, share a high degree of structural similarity with BPA, suggesting that these substitutes may disrupt similar developmental and reproductive pathways. We compared the effects of BPA and BPS on germline and reproductive functions using the genetic model system Caenorhabditis elegans. We found that, similarly to BPA, BPS caused severe reproductive defects including germline apoptosis and embryonic lethality. However, meiotic recombination, targeted gene expression, whole transcriptome and ontology analyses as well as ToxCast data mining all indicate that these effects are partly achieved via mechanisms distinct from BPAs. These findings therefore raise new concerns about the safety of BPA alternatives and the risk associated with human exposure to mixtures. [ABSTRACT FROM AUTHOR]

As a special micro-motion feature of rotor target, rotational angular velocity can provide a discriminant basis for target classification and recognition. In this paper, the authors focus on an efficient rotational angular velocity estimation method of the rotor target is based on the combination of the time–frequency analysis algorithm and Hough transform. In order to avoid the problems of low time–frequency resolution and cross-term interference in short-time Fourier transform and Wigner–Ville distribution algorithm, a modified short-time fractional Fourier transform (M-STFRFT) is proposed to obtain the time-FRFT domain (FRFD)-frequency spectrum with the highest time–FRFD–frequency resolution. In particular, an orthogonal matching pursuit (OMP)-based algorithm is proposed to reduce the computational complexity when estimating the matched transform order in the proposed M-STFRFT algorithm. Firstly, partial transform order candidates are selected randomly from the complete candidates. Then, a partial entropy vector corresponding to partial transform order candidates is calculated from the FRFT results and utilized to reconstruct the complete entropy vector via the OMP algorithm, and the matched transform order can be estimated by searching minimum entropy. Based on the estimated matched transform order, STFRFT is performed to obtain the time–FRFD–frequency spectrum. Moreover, Hough transform is employed to obtain the energy accumulation spectrum, and the micro-Doppler parameter of rotational angular velocity can be estimated by searching the peak value from the energy accumulation spectrum. Both simulated data and measured data collected by frequency modulated continuous wave radar validate the effectiveness of the proposed algorithm. [ABSTRACT FROM AUTHOR]

A modified signal processing and target fusion detection method based on the dual platform cooperative detection model is proposed in this paper. In this model, a single transmitter and dual receiver radar system is adopted, which can form a single radar and bistatic radar system, respectively. Clutter suppression is achieved by an adaptive moving target indicator (AMTI). By combining the AMTI technology and the traditional radar signal processing technology (i.e., pulse compression and coherent accumulation processing), the SNR is improved, and false targets generated by direct wave are suppressed. The decision matrix is obtained by cell averaging constant false alarm (CA-CFAR) and order statistics constant false alarm (OS-CFAR) processing. Then, the echo signals processed in the two receivers are fused by the AND-like fusion rule and OR-like fusion rule, and the detection probability after fusion detection in different cases is analyzed. Finally, the performance of the proposed method is quantitatively analyzed. Experimental results based on simulated data demonstrate that: (1) The bistatic radar system with a split transceiver has a larger detection distance than the single radar system, but the influence of clutter is greater; (2) the direct wave can be eliminated effectively, and no false target can be formed after suppression; (3) the detection probability of the bistatic radar system with split transceivers is higher than that of the single radar system; and (4) the detection probability of signal fusion detection based on two receivers is higher than that of the bistatic radar system and single radar system. [ABSTRACT FROM AUTHOR]

For a conventional narrow-band radar system, the detectable information of the target is limited, and it is difficult for the radar to accurately identify the target type. In particular, the classification probability will further decrease when part of the echo data is missed. By extracting the target features in time and frequency domains from multi-wave gates sparse echo data, this paper presents a classification algorithm in conventional narrow-band radar to identify three different types of aircraft target, i.e., helicopter, propeller and jet. Firstly, the classical sparse reconstruction algorithm is utilized to reconstruct the target frequency spectrum with single-wave gate sparse echo data. Then, the micro-Doppler effect caused by rotating parts of different targets is analyzed, and the micro-Doppler based features, such as amplitude deviation coefficient, time domain waveform entropy and frequency domain waveform entropy, are extracted from reconstructed echo data to identify targets. Thirdly, the target features extracted from multi-wave gates reconstructed echo data are weighted and fused to improve the accuracy of classification. Finally, the fused feature vectors are fed into a support vector machine (SVM) model for classification. By contrast with the conventional algorithm of aircraft target classification, the proposed algorithm can effectively process sparse echo data and achieve higher classification probability via weighted features fusion of multi-wave gates echo data. The experiments on synthetic data are carried out to validate the effectiveness of the proposed algorithm. [ABSTRACT FROM AUTHOR]

Ofloxacin (OFL) has antibacterial and anti‐inflammatory effects on respiratory tract infection, skin soft tissue infection and urogenital tract infection caused by sensitive bacteria. In this study, an electrochemical sensor on account of glassy carbon electrode (GCE) and anthraquinone (AQ)/Vulcan XC‐72 (C) composite was prosperity prepared for the determination of ofloxacin (OFL) drug. The morphology and structure of C/20%AQ composites were characterized by SEM. The electrochemical behavior of OFL on the C/20%AQ/GCE sensor was tested using differential pulse voltammetry (DPV) and cyclic voltammetry (CV). The consequences indicate that the linear response of the sensor to OFL at pH 6.5 in 0.2 M phosphate buffer solution (PBS) was in the scope of 0.1–550.0 μM (R2=0.998) with the limit of detection of 0.01 μM. The prepared C/20%AQ/GCE sensor exhibited good anti‐interference ability and repeatability against OFL. The sensor presents a sensitive, simple and low cost OFL detection method, and has been successfully applied to real samples. [ABSTRACT FROM AUTHOR]