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In response to the poor detection performance of grapes in orchards caused by issues such as leaf occlusion and fruit overlap, this study proposes an improved grape detection method named YOLOv7-MCSF based on the You Only Look Once v7 (YOLOv7) framework. Firstly, the original backbone network is replaced with MobileOne to achieve a lightweight improvement of the model, thereby reducing the number of parameters. In addition, a Channel Attention (CA) module was added to the neck network to reduce interference from the orchard background and to accelerate the inference speed. Secondly, the SPPFCSPC pyramid pooling is embedded to enhance the speed of image feature fusion while maintaining a consistent receptive field. Finally, the Focal-EIoU loss function is employed to optimize the regression prediction boxes, accelerating their convergence and improving regression accuracy. The experimental results indicate that, compared to the original YOLOv7 model, the YOLOv7-MCSF model achieves a 26.9% reduction in weight, an increase in frame rate of 21.57 f/s, and improvements in precision, recall, and mAP of 2.4%, 1.8%, and 3.5%, respectively. The improved model can efficiently and in real-time identify grape clusters, providing technical support for the deployment of mobile devices and embedded grape detection systems in orchard environments. [ABSTRACT FROM AUTHOR]

This paper reports the structure and order degree changes of double perovskite La2CoMnO6 induced by Sr2+ doping at A-sites (x = 0, 0.2, 0.4, 0.6, 0.8, 1.0), which effectively regulates the electrical and magnetic properties. The evolution of the four-phase structure is from the orthogonal (pbnm, disordered) and monoclinic (P21/n, ordered) mixed phases of La2CoMnO6 (x = 0) to the rhombohedral (R3c) phase of La1.6Sr0.4CoMnO6, and finally to the cubic phase (Fm3¯m) of LaSrCoMnO6. All samples exhibit the semiconductor behavior of the three-dimensional variable-range hopping model, and the resistivity decreases first and then increases with increasing Sr content. The low resistivity observed in mixed phases (x = 0.6, 0.8) is primarily attributed to the Co2+ to Co3+ (carrier) transition, the B-site disordering of low structural symmetry, and the p-n type transition. In ferromagnetic La2−xSrxCoMnO6, Sr doping induces the transition from high-spin Co2+ (t2g5eg2) to high-spin Co3+ (t2g4eg2), as well as the superexchange effect from Co2+–O–Mn4+ to Co3+–O–Mn4+. The introduction of a small amount of the cubic phase (x = 0.6) can enhance the bonding energy of the rhombohedral structure, which inhibits the reversal of the magnetic moment, exhibiting a maximum coercive force (Hc = 7.92 kOe). The discovery of rhombohedral and cubic biphase synergistic effect provides a new idea for the modification design of double perovskite materials. [ABSTRACT FROM AUTHOR]

In order to solve the problems of a high mismatching rate and being easily affected by noise and gray transformation, an improved product defect detection method combining centroid distance and textural information is proposed in this paper. Based on image preprocessing, the improved fuzzy C-means clustering method is used to extract the closed contour features. Then, the contour center distance description operator is used for bidirectional matching, and a robust coarse matching contour pair is obtained. After the coarse matching contour pair is screened, the refined matching result is obtained by using the improved local binary pattern operator. Finally, by comparing whether the number of fine matching pairs is consistent with the number of template outlines, the detection of good and bad industrial products is realized, and the closed contour extraction experiment, the anti-rotation matching experiment, the anti-gray difference matching experiment, and the defect detection experiment of three different products are designed. The experimental results show that the improved product defect detection method has good performance in relation to anti-rotation transformation and anti-gray difference, the detection accuracy can reach more than 90%, and the detection time is up to 362.6 ms, which can meet the requirements of industrial real-time detection. [ABSTRACT FROM AUTHOR]

We report the laser-induced voltage (LIV) signals in cubic phase Sr3YCo4O10.5+δ (CP-SYCO) thin films with a c-axis tilted and discuss the relationship between the LIV signals and magnetic anisotropy. CP-SYCO thin films were epitaxially deposited on 0°, 5°, 10°, 15°, and 20° miscut LaAlO3 (001) substrates using pulsed laser deposition (laser energy of 200 mJ, post-annealed at 760 °C). The peak voltage of the LIV for the 15° tilted CP-SYCO film is 310 mV (under laser energy of 400 mJ/pulse), with a rising edge of 26 ns. Compared with G-type antiferromagnetic ordered tetragonal phase Sr3YCo4O10.5+δ(OT-SYCO, deposited at a laser energy of 300 mJ, post-annealed at 790 °C) film, the CP-SYCO exhibits much stronger magnetization anisotropy along in-plane and out-plane due to the possible A-type antiferromagnetic moment arrangement. CP-SYCO films also demonstrate significant thermoelectric anisotropy, supporting the transverse thermoelectric effect, which is partially attributed to the contribution of spin entropy. This study provides an understanding of the anisotropic behavior in atomic layer thermoelectric stack materials and explores magnetic anisotropic material systems. [ABSTRACT FROM AUTHOR]

Aiming at the problems of the poor robustness and universality of traditional contour matching algorithms in engineering applications, a method for improving the surface defect detection of industrial products based on contour matching algorithms is detailed in this paper. Based on the image pyramid optimization method, a three-level matching method is designed, which can quickly obtain the candidate pose of the target contour at the top of the image pyramid, combining the integral graph and the integration graph acceleration strategy based on weak classification. It can quickly obtain the rough positioning and rough angle of the target contour, which greatly improves the performance of the algorithm. In addition, to solve the problem that a large number of duplicate candidate points will be generated when the target candidate points are expanded, a method to obtain the optimal candidate points in the neighborhood of the target candidate points is designed, which can guarantee the matching accuracy and greatly reduce the calculation amount. In order to verify the effectiveness of the algorithm, functional test experiments were designed for template building function and contour matching function, including uniform illumination condition, nonlinear condition and contour matching detection under different conditions. The results show that: (1) Under uniform illumination conditions, the detection accuracy can be maintained at about 93%. (2) Under nonlinear illumination conditions, the detection accuracy can be maintained at about 91.84%. (3) When there is an external interference source, there will be a false detection or no detection, and the overall defect detection rate remains above 94%. It is verified that the proposed method can meet the application requirements of common defect detection, and has good robustness and meets the expected functional requirements of the algorithm, providing a strong technical guarantee and data support for the design of embedded image sensors in the later stage. [ABSTRACT FROM AUTHOR]

Objective To investigate the role of NTSR1 gene in the proliferation and invasion of gastric cancer cells and its possible mechanism. Methods The relationship between expression of NTSR1 protein and EGFR, HER2 in 233 cases of gastric cancer was analyzed by Envision two-step immunohistochemistry. The expression of NTSR1 mRNA in gastric cancer cell line was detected, and the cell line with high abundance was selected as the experimental object. MKN-45 cells with the highest interference efficiency of shNTSR1 were constructed. MTT and cell invasion assay were used to detect the effect of NTSR1 gene silencing on the proliferation and invasion of gastric cancer cells. The effect of shNTSR1 on the expression of 19 related genes in the Cancer Phenotype signaling pathway, including EGFR and HER2, was investigated. Results (1) There was a significant positive correlation between the positive expression of NTSR1 and the expression of EGFR and HER2 in 233 cases of gastric cancer(P < 0.05), and there was a significantly positive correlation between EGFR and HER2 expression(P < 0.05). (2) The expression abundance of NTSR1 in MKN-45 cells was high. (3) The NTSR1 shRNA expression vector was successfully constructed to construct stable cell lines. (4) The proliferation of MKN-45 cells was significantly down-regulated by NTSR1 shRNA interference (P < 0.05). (5) The invasion and metastasis rates of MKN-45 were significantly decreased by NTSR1 shRNA interference(P < 0.05). (6) The expression of p27Kip1 protein in Cancer Phenotype signaling pathway of MKN-45 cells was significantly up-regulated, meanwhile, EGFR, HER2, EpCAM and Met also showed a significant downward trend by NTSR1 shRNA interference(P < 0.05). Conclusion NTSR1 plays an important role in the occurrence, invasion and metastasis of gastric cancer by regulating EGFR/HER2 signaling pathway and P27 Kip1, EpCAM, Met and other Cancer Phenotype signaling pathways.

The SrCoO3−δ system has broad application potential due to its diverse crystal structures, oxidation stoichiometric ratio, and significant electrical and magnetic properties. However, it faces the challenges of a complex crystal structure and oxygen defect control in this material system. Herein, we introduce oxygen defects into SrCoO3−δvia Er doping to regulate the structural, electrical and magnetic transport properties. Sr1−xErxCoO3−δ (x = 0–0.25) undergoes an evolution of structure and oxygen content (measured using the iodometric method) from hexagonal SrCoO2.626 (H + Co3O4) to cubic perovskite Sr0.9Er0.1CoO2.689 (CP) and finally to ordered tetragonal Sr0.8Er0.2CoO2.635 (OT). Among the three phases, Sr0.9Er0.1CoO2.689 (CP) exhibits the lowest resistivity, only 4.06 mΩ cm at room temperature, which is attributed to its high three-dimensional symmetry, overlap of O 2p and Co 3d orbitals at high oxygen ion concentration. Further introduction of Er ions and oxygen defects promotes the transformation from low spin Co4+ (LS, t 52g e 0g , S = 1/2) to high spin Co3+ (HS, t 42g e 2g , S = 2), and from the CoO6 octahedron (low magnetic moment transformation) to the CoO4.25 tetrahedron (high magnetic moment). The oxygen-deficient CoO4.25 layer appears, which can enhance the ordering of A sites and oxygen vacancies, and the CP phase transforms into room-temperature ferromagnetic Sr0.8Er0.2CoO2.635 (OT, TC∼330 K). Er ions provide unpaired electrons in the 2f orbital, which results in a strong magnetization of Sr0.8Er0.2CoO2.635 (OT, 4.66 μB/Co) at low temperatures. [ABSTRACT FROM AUTHOR]

CuCr1-xMgxO2 (x = 0, 0. 005, 0. 010, 0. 020, 0. 030, 0. 040, 0. 050) polycrystals with c-axis preferred orientation were prepared by solid phase reaction method. The effects of Mg2+ doping on the microstructure orientation, electrical properties, and anisotropy of CuCrO2 polycrystals from the vertical and parallel macroscopic in-plane and thickness directions were investigated. The mechanism of Mg doping enhancing the anisotropy of the electrical conductivity in CuCrO2 ceramics was explored. When x ≤ 0. 030, the polycrystals exhibit a rhombohedral R3m single-phase structure, with grain growth predominantly occurring within the surface plane. This led to a reduction in the presence of gas pores and grain boundaries, resulting in the increase of density. The polycrystals demonstrated thermally activated semiconductor electrical transport behavior. When x = 0. 030, the in-plane orientation factor F(00l) reaches its highest value of 0. 912, indicating a significantly enhanced c-axis preferred orientation within the surface plane compared to the thickness direction. The room temperature resistivity of CuCr1-xMgxO2 polycrystals in the in-plane and thickness directions decrease significantly to 1. 80 x 10-3 and 3. 16 x 10-3 Ω•m, respectively. This difference in electrical performance between the two directions was closely related to the structural anisotropy. The thermal activation energy decreased to 0. 03 eV, and the c-axis preferred orientation has no significant influence on the thermal activation energy. The maximum carrier concentration increase by three orders of magnitude compared to the parent phase, indicating fewer grain boundary defects, an increased average free path, enhanced transport capacity, and higher conductivity. The experimental results reveal that the optimal doping concentration is x = 0. 030. When the doping level exceeded 0. 030, the spinel phase MgCr2O4 appeared as an impurity, resulting in a deterioration of the microstructure and electrical transport properties of the samples. [ABSTRACT FROM AUTHOR]

The development of high performance two-dimensional thermoelectric (TE) materials is crucial for enhancing the conversion of waste heat into electricity and for achieving the transition to new energy. In recent years, two-dimensional Dirac materials with high carrier mobility and non-trivial topological properties have been expected to extend the application of carbon-based materials in the TE field. However, research on the TE properties of two-dimensional Dirac materials is still scarce, and the relevant physical mechanisms that affect the TE figure of merit of the materials are still unclear. Therefore, we carefully selected a typical and experimentally synthesized Dirac structure, graphenylene, and systematically studied its thermal transport and electrical transport properties using density functional theory (DFT) and Boltzmann transport theory. The results show that the ZT value of graphenylene exhibits an extremely significant anisotropy. There is a significant discrepancy in the figure of merit (ZT) values of n-type and p-type systems at the optimum doping concentration, i.e., the ZT value of the n-type system (0.49) is one order of magnitude greater than that of the p-type system (0.06). Graphenylene exhibits excellent electronic performance due to its unique electronic band structure and has an extremely high conductivity (for the n-type system, electrical conductivity at room temperature is 109 S m−1). Interestingly, graphenylene has an unusually higher ZT at low temperature (0.5 at 300 K) than at high temperature (0.3 at 800 K) for n-type doping along the x-axis, contrary to the conventional view that higher ZT values exist in the high temperature range. This work provides a deep insight into the TE properties of two-dimensional Dirac carbon materials and offers new perspectives for enhancing the TE performance and application of carbon-based nanomaterials. [ABSTRACT FROM AUTHOR]

The ordering and arrangement of atoms in double perovskite structures play a crucial role in determining their electrical and magnetic properties. In this groundbreaking study, we conducted thermogravimetric-differential scanning calorimetry analysis on the La2CoMnO6 (LCMO) raw material, shedding light on the remarkable oxygen absorption process that occurs during the phase formation of LCMO. Therefore, LCMO ceramics with double perovskite structure were synthesized by solid-state reaction combined with oxygen pressure annealing (1200 °C/10 h/Po2 = 0.15 MPa). The structure and properties of the samples before and after oxygen pressure annealing (OPA) were characterized using X-ray diffraction with Rietveld refinement fitting, X-ray photoelectron spectroscopy, resistivity, dielectric and magnetic measurements. Subsequently, we thoroughly explored the influence of the degree of B-site (Co/Mn) ordering on the electrical and magnetic properties of the samples. The results show that the Co2+/Mn4+ content of OPA-LCMO is increased, the fraction of the B-site ordering phase (P21/n) increased by 30%, the magnetization is increased by 7.5 emu/g and the Curie temperature is increased to 216 K with the increase of Co2+–O–Mn4+ arrangement. At the same time, due to the decrease of oxygen vacancy and disordering phase (Pbnm), the carrier mobility of OPA-LCMO is reduced, and the resistivity (T = 300 K) is increased by 20 times. This comprehensive study sheds light on the intricate relationship between OPA, B-site ordering degree, and the resulting magnetic and electrical properties of double perovskite materials. These findings significantly contribute to our understanding and pave the way for the improved design and development of advanced double perovskite materials. [ABSTRACT FROM AUTHOR]

Objectives: We aim to retrospectively analyze the diagnostic image quality of transvaginal 4‐dimensional hysterosalpingo‐contrast sonography from infertile patients and determine the significant influencing factors. Methods: A total of 445 patients visiting infertility clinics were included in the study, of which 167 were primary infertile and 278 were secondary infertile. The factors were recorded, including age; examination time; infertility type; history of pelvic inflammatory disease, pelvic surgery, intrauterine surgery, and ectopic pregnancy; endometrial thickness; uterine position; ovarian position; 2‐dimensional image quality; intravasation quantity, position, and time; balloon volume; and the dosage of contrast agent or the sterile saline solution. All the factors were compared among different diagnostic image quality groups. The method of rank logistic regression analysis was adopted to analyze the risk factors affecting the diagnostic image quality. Results: Among the 445 infertile patients, 124 (27.9%) patients had intravasation occur during transvaginal 4‐dimensional hysterosalpingo‐contrast sonography. The diagnostic image quality between the 2 sonographers was consistent (Cronbach's alpha, 0.993). Different intravasation quantities, positions, and times; increased of balloon volume; and history of pelvic surgery were substantial risk factors for the diagnostic image quality. The diagnostic image quality diminished with the increase of intravasation. In the patient with cornual intravasation, the diagnostic image quality was substantially worse than that with non–cornual intravasation. Moreover, early onset of intravasation seriously affected the diagnostic image quality. Conclusions: In conclusion, intravasation affected the diagnostic image quality, especially early cornual massive intravasation. [ABSTRACT FROM AUTHOR]