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Objective A finite element model of metro vehicle air compressor frame is established and verified through modal testing and vibration testing. It is found that the vertical bending modal frequency of the dryer frame coincides with motor harmonic frequency and the vibration isolation rate is relatively low. Under the premise of meeting modal frequency and vibration isolation rate requirements, a structural optimization design of air compressor frame is carried out by integrating finite element method and optimization techniques. Method Taking the thickness of the air compressor frame as the optimization variable, DOE (design of experiment) is firstly carried out to obtain different samples of air compressor frame, then an approximate model of air compressor frame is established using the Moving Least Squares method. Based on this approximate model, with vertical first-order bending modal frequency of the frame, vertical bending modal frequency of dryer frame and vibration isolation rate as optimization objectives, an optimization design is performed using the adaptive response surface method to obtain the optimal scheme of frame parameters. Result & Conclusion Results show that, compared to before optimization, the vertical first-order bending and the dryer frame vertical bending modal frequencies after optimization are both more than 3.0 Hz different from the rail excitation frequency (typically 15.0 Hz), motor rotation fundamental frequency (24.5 Hz), and harmonics; reaching the optimal avoidance of resonance conditions, and the vibration isolation rate can be increased by 20% to 25%, while the total mass only increases by 6%.

Background and purpose: According to the 2020 global cancer burden data of the International Agency for Research on Cancer (IARC), breast cancer has replaced lung cancer as the most common type of cancer worldwide. The aim of this study was to conduct a bibliometric and visual analysis of breast reconstruction related research in China and abroad published in the past 5 years, to understand the research status and development trend in this field, to discuss the focus of research in different countries and different disciplines, and to provide reference for other researchers. Methods: Relevant literatures about breast reconstruction were retrieved from the Web of Science Core Collection. The VOS viewer 1.6.15 software was used to extract the authors, countries, institutions and keywords to generate network maps of high-yield authors, institutions and high-frequency keywords clustering network. Results: A total of 4 815 documents meeting the requirements were retrieved, which showed an upward trend in the past five years. Regarding the discipline, 838 documents (17.40%) were published by breast surgery and Cancer Surgery, 3 308 (68.70%) were published by plastic surgery, and 669 (13.90%) were jointly published by both types of researchers. There were differences in the disciplines of the main authors between China and abroad. In China, authors from breast surgery published a larger proportion of documents (138, 44.52%), while the number of documents published by authors of plastic surgery (129, 44.52%) and the joint publication of both types of authors (43, 13.87%) was relatively small. However, foreign documents mainly came from authors of plastic surgery (74.74%). There were more cooperative groups (155) formed by major foreign authors, and more frequent joint publishing between groups, while Chinese authors formed only 16 cooperative groups with less cooperation. Authors from breast surgery focused more on oncology-related issues in breast reconstruction, while in plastic surgery, more attentions were paid on autologous tissue reconstruction. Conclusion: Breast reconstruction has gradually attracted the attention of Chinese and foreign researchers. Compared with foreign countries, there were problems such as lack of high-quality research and less cooperative research in China. There were differences in the research focus of breast reconstruction between China and abroad, which was mainly related to the differences in the disciplines of researchers.

Due to a series of complications associated with traditional axillary lymph node dissection, sentinel lymph node biopsy has now replaced axillary lymph node dissection as the standard axillary staging procedure for patients with negative axillary lymph nodes in both domestic and international clinical practice. With the increased application of breast-conserving surgery and the subsequent increase in the number of patients with ipsilateral breast recurrence after breast-conserving surgery, the appropriate axillary evaluation of such patients has become a new topic of clinical concern, and the application of repeat sentinel lymph node biopsy has become one of the focal points of this topic. It has been shown that repeat sentinel lymph node biopsy is a feasible and safe method for axillary evaluation in patients with ipsilateral breast tumor recurrence after breast-conserving surgery, and that treatment can be adjusted for some patients depending on axillary lymph node status. However, due to the relative lack of studies on the prognostic impact of repeat sentinel lymph node biopsy results and with the development of non-invasive screening techniques, the necessity of repeat sentinel lymph node biopsy in this group of patients remains controversial and needs to be explored in future high-quality prospective trials. This article compiled and summarized the previous literature related to repeat sentinel lymph node biopsy, and focused on its feasibility, safety and clinical application value for clinical reference.

In the past two decades, the survival of HER2-positive early-stage breast cancer patients has significantly improved with the development of HER2-targeted therapies. The focus has been placed on maximizing the clinical benefit of HER2-positive early-stage breast cancer by optimizing the treatment frameworks and therapeutic strategies in this field. In this paper, several important clinical studies of HER2-positive early-stage breast cancer in the neoadjuvant or adjuvant settings will be summarized and analyzed to provide clues for the development of personalized treatment strategies in the future.

To overcome the adverse effects of noise and shadow regions on target detection in side-scan sonar images, more precisely, it is difficult to accurately detect targets, a target detection technology based on a multi-region optimal selection strategy of spectral clustering combined with the entropy weight method is proposed in this study. First, the cluster numbers for spectral clustering are set in advance based on prior knowledge, and the pixels of the sonar image are clustered into several different regions. Second, the invariable features of translation, rotation and scaling up that each region is extracted and used to construct the feature criterion matrix for the multiple regions. Last, the entropy weight method is used to calculate the weights of each feature and the comprehensive weighted score of each region for this feature criterion matrix to obtain the final target region. Experimental results show that the proposed method can effectively overcome the adverse effects of noise and shadow regions in side-scan sonar images, but also achieve the selection of optimal target region among multiple regions after image clustering, thus verifying the feasibility and effectiveness of the proposed method in this study.

Background and purpose: Currently, several studies have demonstrated that body mass index (BMI) is a prognostic factor in breast cancer. The study aimed to assess the association pattern of BMI with mortality risk among patients of different age groups. Methods: This retrospective cohort study included the clinical characteristics and survival status of 25 629 patients diagnosed with breast cancer and subsequently hospitalized in Fudan University Shanghai Cancer Center between January 1, 2008 and December 31, 2016. The association between BMI and prognosis of breast cancer patients in different age subgroups was analyzed using Cox proportional hazards regression model with restricted cubic splines adjusting the main prognostic factors. Results: BMI and age were both influencing factors of breast cancer prognosis, and there was a significant interaction (P = 0.011). The pattern of association between risk of death and BMI differed among different age groups. A "J-shaped" association between risk of death and BMI was observed in the patients younger than 35 years, with a BMI of 20.16 kg/m2 corresponding to the lowest risk of death. In the age group of 35-60 years, no significant change in the risk of death was observed in patients with BMI below 23 kg/m2, and the risk of death in patients with BMI above 23 kg/m2 increased with increasing BMI; A "U-shaped" association between risk of death and BMI was observed in the patients older than 60 years, with a BMI of 23.86 kg/m2 being the lowest. The risk of death was more sensitive to changes in BMI in patients aged less than 35 years than in those aged 35-60 years and those aged more than 60 years. Conclusion: BMI and age have a significant interaction in the prognosis of breast cancer when adjusted for potential confounding factors. The association pattern between the risk of death and BMI of patients in different age groups is different. For patients under 35 years old, the lowest risk of death corresponds to BMI at diagnosis of about 20 kg/m2, while for patients over 60 years old, the lowest risk of death corresponds to a BMI at diagnosis of about 24 kg/m2.

To report the results of a single-arm, prospective partial breast irradiation (PBI) trial from China mainland using a dose of 40.05 Gy in 15 fractions delivered with intensity-modulated radiation therapy (IMRT) technique for patients with early stage breast cancer. Patients aged ≥ 50 years who underwent breast-conserving surgery for unifocal non-lobular invasive breast cancer, with pathological T1 disease, clear margins, negative axillary nodes, and positive hormonal receptors, were recruited. The primary endpoint was 3-year cosmetic deterioration, and secondary endpoints included adverse events, ipsilateral breast tumor recurrence (IBTR), regional recurrence, and survivals. This trial is registered with ClinicalTrials.gov (registration No. NCT03411174). From Jan of 2015 to July of 2018, 208 out of 222 patients recruited were evaluable and included in final analysis. The median follow-up was 66.3 (range: 42.0-105.4) months. The 3-year overall cosmetic deterioration rate was 3.5%. The rates of grade 2 radiation dermatitis and breast induration was 5.8% and 1.5%, respectively. No one experienced ≥ grade 2 breast pain, edema, or telangiectasia. The 5-year cumulative incidence of IBTR and RR was 0.5%. No one developed DM. The 5-year DFS was 99.0%. Four patients died from non-breast cancer causes, and the 5- year OS was 97.9%. In conclusion, we observed lower rates of cosmetic deterioration, IBTR, and ≥ grade 2 acute/late normal tissue effects following PBI with a moderately hypofractionated regimen delivered with IMRT technique. Therefore, this regimen represents an attractive option when an external beam PBI approach is chosen to treat a patient with low-risk early breast cancer. [ABSTRACT FROM AUTHOR]

Information on the population distribution at the building scale can help governments make supplemental decisions to address complex urban management issues. However, the discontinuity and strong spatial heterogeneity of research units at the building scale make it challenging to fuse multi-source geographic data, which causes significant errors in population estimation. To address this problem, this study proposes a method for population estimation at the building scale based on Dual-Environment Feature Fusion (DEFF). The dual environments of buildings were constructed by splitting the physical boundaries and extracting features suitable for the dual-environment scale from multi-source geographic data to describe the complex environmental features of buildings. Meanwhile, Data Quality Weighting based Technique for Order of Preference by Similarity to Ideal Solution (DQW-TOPSIS) method was proposed to assign appropriate weights to the features of the external environment for better feature fusion. Finally, a regression model was established using dual-environment features for building-scale population estimation. The experimental areas chosen for this study were Jianghan and Wuchang Districts, both located in Wuhan City, China. The estimated results of the DEFF were compared with those of the ablation experiments, as well as three publicly accessible population datasets, specifically LandScan, WorldPop, and GHS-POP, at the community scale. The evaluation results showed that DEFF had an ${R^2}$ R 2 of approximately 0.8, Mean Absolute Error (MAE) of approximately 1200, Root Mean Square Error (RMSE) of approximately 1700, and both Mean Absolute Percentage Error (MAPE) and Symmetric Mean Absolute Percentage Error (SMAPE) of approximately 26%, indicating an improved performance and verifying the validity of the proposed method for fine-scale population estimation. [ABSTRACT FROM AUTHOR]

This paper considers comparing properties and characterizations of the bivariate functions under Archimedean copula. It is shown that some results of the usual stochastic order for the bivariate functions in the independent case are generalized to the Archimedean copula-linked dependent case, and we also derive some characterizations of different bivariate functions composed by Archimedean copula-linked dependent random variables. These results generalize some existing results in the literature and bring conclusions closer to reality. Two applications in scheduling problems are also provided to illustrate the main results. [ABSTRACT FROM AUTHOR]

Fast and smooth trajectory planning is crucial for modern control systems, e.g., missiles, aircraft, robots and AGVs. However, classical spline based trajectory planning tools introduce redundant constraints and parameters, leading to high costs of computation and complicating fast and smooth execution of trajectory planning tasks. A new tool is proposed that employs truncated power functions to annihilate some constraints and reduce the number of parameters in the optimal model. It enables solving a simplified optimal problem in a shorter time while keeping the trajectory sufficiently smooth. With an engineering background, our case studies show that the proposed method has advantages over other solutions. It is promising in regard to the demanding tasks of trajectory planning.