The first microRNA was discovered in Caenorhabditis elegans in 1993, and since then, thousands of microRNAs have been identified from almost all eukaryotic organisms examined. MicroRNAs function in many biological eve...The first microRNA was discovered in Caenorhabditis elegans in 1993, and since then, thousands of microRNAs have been identified from almost all eukaryotic organisms examined. MicroRNAs function in many biological events such as cell fate determination, metabolism, apoptosis, and carcinogenesis. So far, more than 250 microRNAs have been identified in C. elegans; however, functions for most of these microRNAs are still unknown. A small number of C. elegans microRNAs are associated with known physiological roles such as developmental timing, cell differentiation, stress response, and longevity. In this review, we summarize known roles of micro- RNAs in neuronal differentiation and function of C. elegans, and discuss interesting perspectives for future studies.展开更多
Tool wear is a noteworthy problem in the process of shield tunneling,and the degree of wear varies with stratum.The sand-pebble strata in Beijing are typically mechanically unstable.However,many subways are buried who...Tool wear is a noteworthy problem in the process of shield tunneling,and the degree of wear varies with stratum.The sand-pebble strata in Beijing are typically mechanically unstable.However,many subways are buried wholly or partially in sand-pebble strata.Taking the Beijing New Airport line tunneling project as research background,this study evaluated the wear characteristics of the multiconfiguration rippers of a 9-m-diameter spoke-type shield tunneling machine in a sand-pebble stratum.The wear values of five ripper teeth and ripper flanks were analyzed based on field-measured data from the Beijing New Airport line project.As the analytical results show,the wear value generally increases as the installation radius enlarges with the rise of cutting trace length.The wear of the 190-rippers was divided into five categories:pedestal wear,ripper teeth collapse,uniform wear,ripper teeth falling off and ripper flank wear.Uniform wear of the ripper teeth and ripper flank wear were the two abrasion types of the 190-rippers.The teeth of the 155-rippers mostly maintained their cutting capacity under the protection of the 190-rippers.A wear prediction model of linear fitting field data was developed for a 190-ripper face to obtain the optimum shield driving distance in the sand-pebble stratum.The average wear coefficients of the 190-ripper before and after replacement matched well,being 0.045 and 0.066 mm/km,respectively.The results of this study provide a theoretical reference for tool wear prediction in shield construction under similar geological conditions.展开更多
It is important for the autonomous system to understand environmental information.For the autonomous system,it is desirable to have a strong generalization ability to deal with different complex environmental informat...It is important for the autonomous system to understand environmental information.For the autonomous system,it is desirable to have a strong generalization ability to deal with different complex environmental information,as well as have high accuracy and quick inference speed.Network ensemble architecture is a good choice to improve network performance.However,it is unsuitable for real-time applications on the autonomous system.To tackle this problem,a new neural network ensemble named partial-shared ensemble network(PSENet)is presented.PSENet changes network ensemble architecture from parallel architecture to scatter architecture and merges multiple component networks together to accelerate the inference speed.To make component networks independent of each other,a training method is designed to train the network ensemble architecture.Experiments on Camvid and CIFAR-10 reveal that PSENet achieves quick inference speed while maintaining the ability of ensemble learning.In the real world,PSENet is deployed on the unmanned system and deals with vision tasks such as semantic segmentation and environmental prediction in different fields.展开更多
Uroflowmetry is an uroflow measurement technique used to record the voided volume(VV)and flow rate,which can help clinicians objectively evaluate lower urinary tract function.Currently,few uroflowmetry studies have fo...Uroflowmetry is an uroflow measurement technique used to record the voided volume(VV)and flow rate,which can help clinicians objectively evaluate lower urinary tract function.Currently,few uroflowmetry studies have focused on the female population,[1]especially on the uroflow curve standard analysis.Hence,we sought to establish dependable uroflow reference values and nomograms for Chinese women and to evaluate the relationship between uroflow patterns and demographic data.展开更多
Metastatic pheochromocytoma/paraganglioma(MPP)is a rare endocrine tumor that originates from extra-adrenal chromaffin cells such as the paraganglia cells of sympathetic and parasympathetic nerves.It usually causes mul...Metastatic pheochromocytoma/paraganglioma(MPP)is a rare endocrine tumor that originates from extra-adrenal chromaffin cells such as the paraganglia cells of sympathetic and parasympathetic nerves.It usually causes multiple solid tumors and exhibits strong aggressiveness with poor prognosis,with a reported 5-year survival rate of less than 50%.Cases of brain and retroperitoneal metastases at the initial diagnosis have not yet been reported.We report a 41-year-old male patient initially diagnosed with MPP in the brain and retroperitoneum who underwent multi-disciplinary collaborative surgery and simultaneous removal of two tumors at our center.Postoperative pathology revealed infiltrative growth of a skull base tumor.The patient chose to receive the tyrosine kinase inhibitor sunitinib as a targeted treatment.A 3-month follow-up after surgery showed that the patient recovered well without signs of metastasis or recurrence.We present multi-disciplinary surgery under similar circumstances for enhanced treatment and postoperative management.The patient demonstrates a favorable prognosis during postoperative follow-up,indicating that simultaneous multidisciplinary surgery may offer greater benefits for MPP patients.展开更多
基金funded by the State Key Development Programme for Basic Research of China(No.2011CBA01103)the National Natural Science Foundation of China(Nos.31071132,91232702,and 81171074)Program for New Century Excellent Talents in University(No.2010ZD022)
文摘The first microRNA was discovered in Caenorhabditis elegans in 1993, and since then, thousands of microRNAs have been identified from almost all eukaryotic organisms examined. MicroRNAs function in many biological events such as cell fate determination, metabolism, apoptosis, and carcinogenesis. So far, more than 250 microRNAs have been identified in C. elegans; however, functions for most of these microRNAs are still unknown. A small number of C. elegans microRNAs are associated with known physiological roles such as developmental timing, cell differentiation, stress response, and longevity. In this review, we summarize known roles of micro- RNAs in neuronal differentiation and function of C. elegans, and discuss interesting perspectives for future studies.
基金National Natural Science Foundation of China,Grant/Award Numbers:51608521,52178375Fundamental Research Funds for the Central Universities,Grant/Award Number:2022YQLJ01Major Achievements Transformation and Industrialization Projects of Central Universities in Beijing,Grant/Award Number:ZDZH20141141301。
文摘Tool wear is a noteworthy problem in the process of shield tunneling,and the degree of wear varies with stratum.The sand-pebble strata in Beijing are typically mechanically unstable.However,many subways are buried wholly or partially in sand-pebble strata.Taking the Beijing New Airport line tunneling project as research background,this study evaluated the wear characteristics of the multiconfiguration rippers of a 9-m-diameter spoke-type shield tunneling machine in a sand-pebble stratum.The wear values of five ripper teeth and ripper flanks were analyzed based on field-measured data from the Beijing New Airport line project.As the analytical results show,the wear value generally increases as the installation radius enlarges with the rise of cutting trace length.The wear of the 190-rippers was divided into five categories:pedestal wear,ripper teeth collapse,uniform wear,ripper teeth falling off and ripper flank wear.Uniform wear of the ripper teeth and ripper flank wear were the two abrasion types of the 190-rippers.The teeth of the 155-rippers mostly maintained their cutting capacity under the protection of the 190-rippers.A wear prediction model of linear fitting field data was developed for a 190-ripper face to obtain the optimum shield driving distance in the sand-pebble stratum.The average wear coefficients of the 190-ripper before and after replacement matched well,being 0.045 and 0.066 mm/km,respectively.The results of this study provide a theoretical reference for tool wear prediction in shield construction under similar geological conditions.
基金supported by the National Key Research and Development Program of China under Grant 2019YFC1511401the National Natural Science Foundation of China under Grant 62173038 and 61103157+1 种基金Science Foundation for Young Scholars of Tobacco Research Institute of Chinese Academy of Agricultural Sciences under Grant 2021B05Key Scientific and Tech-nological Research and Development Project of China National Tobacco Corporation under Grant 110202102007.
文摘It is important for the autonomous system to understand environmental information.For the autonomous system,it is desirable to have a strong generalization ability to deal with different complex environmental information,as well as have high accuracy and quick inference speed.Network ensemble architecture is a good choice to improve network performance.However,it is unsuitable for real-time applications on the autonomous system.To tackle this problem,a new neural network ensemble named partial-shared ensemble network(PSENet)is presented.PSENet changes network ensemble architecture from parallel architecture to scatter architecture and merges multiple component networks together to accelerate the inference speed.To make component networks independent of each other,a training method is designed to train the network ensemble architecture.Experiments on Camvid and CIFAR-10 reveal that PSENet achieves quick inference speed while maintaining the ability of ensemble learning.In the real world,PSENet is deployed on the unmanned system and deals with vision tasks such as semantic segmentation and environmental prediction in different fields.
文摘Uroflowmetry is an uroflow measurement technique used to record the voided volume(VV)and flow rate,which can help clinicians objectively evaluate lower urinary tract function.Currently,few uroflowmetry studies have focused on the female population,[1]especially on the uroflow curve standard analysis.Hence,we sought to establish dependable uroflow reference values and nomograms for Chinese women and to evaluate the relationship between uroflow patterns and demographic data.
基金This study was supported by the National Key Research and Development Program of China(No.2018YFC2002202)the National High-Level Hospital Clinical Research Funding(No.BJ-2021-184).
文摘Metastatic pheochromocytoma/paraganglioma(MPP)is a rare endocrine tumor that originates from extra-adrenal chromaffin cells such as the paraganglia cells of sympathetic and parasympathetic nerves.It usually causes multiple solid tumors and exhibits strong aggressiveness with poor prognosis,with a reported 5-year survival rate of less than 50%.Cases of brain and retroperitoneal metastases at the initial diagnosis have not yet been reported.We report a 41-year-old male patient initially diagnosed with MPP in the brain and retroperitoneum who underwent multi-disciplinary collaborative surgery and simultaneous removal of two tumors at our center.Postoperative pathology revealed infiltrative growth of a skull base tumor.The patient chose to receive the tyrosine kinase inhibitor sunitinib as a targeted treatment.A 3-month follow-up after surgery showed that the patient recovered well without signs of metastasis or recurrence.We present multi-disciplinary surgery under similar circumstances for enhanced treatment and postoperative management.The patient demonstrates a favorable prognosis during postoperative follow-up,indicating that simultaneous multidisciplinary surgery may offer greater benefits for MPP patients.
