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The climbing pinion is an important part of the jacking system of a self-elevating platform and the manufacturing of super-large module climbing pinions belongs to the extreme processing requiring high manufacturing technology. Rough tooth processing, heat treatment process test and finished tooth processing are the key technologies in manufacturing super-large module climbing pinions. The improved oxygen-gas NC flame cutting technology is used for rough teeth, which can make the tooth flank and tooth root after quenching and tempering treatment obtain surface hardness above 330 HB. To study the mechanical properties of climbing pinions after quenching and tempering treatment, the material performance test is performed on the specimens taken from climbing pinion forgings, and the results show that the tensile property and impact energy of the materials meet the mechanical property requirements. NC milling technology is used to process finished teeth of climbing pinions, and the results show that the roughness of tooth surface of climbing pinions can be controlled within Ra=6.3 μm, and the deviation of common normal length can be controlled within 0.2 mm. The manufacturing process and control measures of the above key links ensure that the finished product quality of climbing pinions can meet the technical requirements.

The current scheme of manually extracting features for object detection has been replaced by deep learning. Deep learning technology has greatly promoted the development of object detection technology. Object detection has also become one of the most important application fields of deep learning. Object detection is to simultaneously predict the category and position of object instances in a given image. This technology has been widely used in medical imaging, remote sensing technology, monitoring and security, automatic driving and other fields. However, with the diversification of object detection application fields, the imbalance problem in the application of deep learning to object detection has become a new entry point to optimize the object detection training model. This paper mainly analyzes the use of machine learning technology to solve the object detection problem. There are four kinds of imbalance problems in each training stage of the model: data imbalance, scale imbalance, relative space imbalance and classification and regression imbalance. This paper analyzes the main reasons for the problem, studies representative classical solutions, and expounds the problems existing in object detection in various fields. By analyzing and summarizing the object detection imbalance problems, this paper discusses the directions of the imbalance of object detection in the future.

Objective: To determine the precise quantitative relationship between screening efficiency and motion parameters for reciprocating vibrating screen, and to obtain the movement parameters with the optimal screening efficiency. Methods: Rocky was adopted to accurately simulate the movement behavior for wheat grain and wheat stem in the screening process, many factors orthogonal simulation test was used to investigate the effect of vibration frequency, amplitude, vibrating direction angle and screen surface inclination angle on screening efficiency. Results: The movement behaviors of wheat in the screening process was consistent with the theory analysis, which verified the correctness and feasibility of numerical simulation using Rocky. The vibration frequency, amplitude, vibrating direction angle and screen surface inclination angle have significant influence on the screening efficiency, and there is significant interaction between these motion parameters. The optimal motion parameter combination was the vibration frequency of 10 Hz, the amplitude of 2 mm, the vibration direction angle of 45° and the screen surface inclination angle of 0°. Conclusion: A regression model reflecting the quantitative relationship between motion parameters of and screening efficiency for reciprocating vibrating screen was established, and the optimal motion parameter combination of reciprocating vibrating screen was obtained.

Objective To study the correlation between the time from rapid eye movement sleep behavior disorder (RBD) to disease onset and the clinical characteristics of Parkinson's disease (PD). Methods A total of 123 PD patients were recruited from Tianjin Huanhu Hospital between September 2019 and December 2021. All participants were divided into the group with RBD (41 cases) and the group without RBD (82 cases) according to the probable RBD criteria. Hoehn ⁃Yahr staging was used to evaluate PD grade. Unified Parkinson's Disease Rating Scale Ⅲ (UPDRS Ⅲ) was used to evaluate the motor function of PD. Mini⁃Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), Hamilton Anxiety Rating Scale (HAMA) and Hamilton Depression Rating Scale (HAMD), Parkinson's Disease Sleep Scale (PDSS), and Non ⁃ Motor Symptom Scale (NMSS) were used to evaluate cognitive function, anxiety, depression, sleep and total non ⁃ motor symptoms. The life quality of patients was evaluated by 39 ⁃ Item Parkinson's Disease Questionnaire (PDQ ⁃ 39). Spearman rank correlation analysis was used to explore the correlation between the time from RBD to disease onset and clinical characteristics in PD. Results UPDRS Ⅲ (t = ⁃ 2.703, P = 0.008) and NMSS (t = ⁃ 2.176, P = 0.032) scores of PD with RBD group were higher than those of the PD without RBD group. The time from the RBD to the onset of PD was posit correlated with NMSS score (rs = 0.547, P = 0.001). Conclusions The motor and non ⁃ motor symptoms in PD patients with RBD are more severe than those of patients without RBD. Early onset of RBD in prodromal period may indicates more severe non⁃motor symptoms in future.

This paper examines the impact of managerial ability on bank loan contracting. We find that firms with higher‐ability managers obtain more favourable loan contract terms, including lower loan spreads, fewer covenants, and more short‐term maturities. Furthermore, the negative relation between managerial ability and loan spread is concentrated in firms with higher information asymmetry, higher default risk, or lower agency costs of debt. Finally, we find that firms with higher‐ability managers are more likely to choose public bonds over bank loans. [ABSTRACT FROM AUTHOR]

Fabry disease (FD) is a rare X chromosome‐linked disorder and can be easily misdiagnosed. Here, we report the case of a 69‐year‐old male patient with FD who developed heart failure and showed extremely high pulmonary artery pressure. His initial symptom was recurrent atrial fibrillation. The left and right atrial inner diameters were large, and the ventricular wall was thick. Gene analysis which showed GLA c.215T>C p.Met72Thr mutation and single photon emission computed tomography indicated the diagnosis of FD with coronary microvascular dysfunction. The patient was prescribed anti‐heart failure drugs, including vericiguat. Following the treatment, his heart function and microvascular perfusion significantly improved, which might be due to the beneficial effects of vericiguat. [ABSTRACT FROM AUTHOR]

Intratumoral immune status influences tumor therapeutic response, but it remains largely unclear how the status determines therapies for patients with intrahepatic cholangiocarcinoma. Here, we examine the single-cell transcriptional and TCR profiles of 18 tumor tissues pre- and post- therapy of gemcitabine plus oxaliplatin, in combination with lenvatinib and anti-PD1 antibody for intrahepatic cholangiocarcinoma. We find that high CD8 GZMB+ and CD8 proliferating proportions and a low Macro CD5L+ proportion predict good response to the therapy. In patients with a poor response, the CD8 GZMB+ and CD8 proliferating proportions are increased, but the CD8 GZMK+ proportion is decreased after the therapy. Transition of CD8 proliferating and CD8 GZMB+ to CD8 GZMK+ facilitates good response to the therapy, while Macro CD5L+–CD8 GZMB+ crosstalk impairs the response by increasing CTLA4 in CD8 GZMB+. Anti-CTLA4 antibody reverses resistance of the therapy in intrahepatic cholangiocarcinoma. Our data provide a resource for predicting response of the combination therapy and highlight the importance of CD8+T-cell status conversion and exhaustion induced by Macro CD5L+ in influencing the response, suggesting future avenues for cancer treatment optimization. The role of the tumor microenvironment in immunotherapy response in intrahepatic cholangiocarcinoma remains unclear. Here, single cell RNA and TCR sequencing of samples before and after immunotherapy highlights the role of CD8 T-cell status conversion and exhaustion induced by Macro CD5L+ in treatment response. [ABSTRACT FROM AUTHOR]

Two isostructural lanthanide complexes were synthesized by solvent evaporation with 3-dimethylaminobenzoic acid and 5,5′-dimethyl-2,2′-bipyridine as ligands. The general formula of the structure is a [Ln(3-N,N-DMBA)3(5,5′-DM-2,2′-bipy)]2·2(3-N,N-DMHBA), Ln = (Gd(1), Tb(2)), 3-N,N-DMBA = 3-Dimethylamino benzoate, 5,5′-DM-2,2′-bipy = 5,5′-dimethyl-2,2′ bipyridine. Both complexes exhibited dimeric structures based on X-ray diffraction analysis. At the same time, infrared spectroscopy and Raman spectroscopy were used to measure the spectra of the complex. A thermogravimetric infrared spectroscopy experiment was performed to investigate the thermal stability and decomposition mechanism of the complexes. Measurements of the low-temperature heat capacity of the complexes were obtained within the temperature range of 1.9 to 300 K. The thermodynamic function was calculated by heat capacity fitting. In addition, the fluorescence spectra of complex 2 were studied and the fluorescence lifetime values were determined, and the energy transfer mechanism of complex 2 was elucidated. [ABSTRACT FROM AUTHOR]