This paper aims to propose a modeling framework for subway operation and maintenance system (SOMS), which analyzes the train condition data based on both train sensor network data and basis train maintenance plan. The...This paper aims to propose a modeling framework for subway operation and maintenance system (SOMS), which analyzes the train condition data based on both train sensor network data and basis train maintenance plan. The system is formulated into five function modules, and the research problem is to determine one auxiliary maintains plan, including the time allocation and frequency of maintenance. The case of Guangzhou metro is conducted to illustrate the applicability of SOMS, and the results reveal a number of interesting insights into subway maintenance system, i.e., the worksheet can reduce duplication of redundant maintenance work, the repair cost, and the damage caused by frequent disassembly.展开更多
The outbreak of coronavirus disease 2019(COVID-19) caused by SARS-CoV-2 has created a global health crisis. SARS-CoV-2 infects varieties of tissues where the known receptor ACE2 is low or almost absent, suggesting the...The outbreak of coronavirus disease 2019(COVID-19) caused by SARS-CoV-2 has created a global health crisis. SARS-CoV-2 infects varieties of tissues where the known receptor ACE2 is low or almost absent, suggesting the existence of alternative viral entry pathways. Here, we performed a genome-wide barcoded-CRISPRa screen to identify novel host factors that enable SARS-CoV-2 infection. Beyond known host proteins, i.e., ACE2, TMPRSS2, and NRP1, we identified multiple host components,among which LDLRAD3, TMEM30A, and CLEC4G were confirmed as functional receptors for SARS-CoV-2. All these membrane proteins bind directly to spike’s N-terminal domain(NTD). Their essential and physiological roles have been confirmed in either neuron or liver cells. In particular, LDLRAD3 and CLEC4G mediate SARS-CoV-2 entry and infection in an ACE2-independent fashion. The identification of the novel receptors and entry mechanisms could advance our understanding of the multiorgan tropism of SARS-CoV-2, and may shed light on the development of COVID-19 countermeasures.展开更多
文摘This paper aims to propose a modeling framework for subway operation and maintenance system (SOMS), which analyzes the train condition data based on both train sensor network data and basis train maintenance plan. The system is formulated into five function modules, and the research problem is to determine one auxiliary maintains plan, including the time allocation and frequency of maintenance. The case of Guangzhou metro is conducted to illustrate the applicability of SOMS, and the results reveal a number of interesting insights into subway maintenance system, i.e., the worksheet can reduce duplication of redundant maintenance work, the repair cost, and the damage caused by frequent disassembly.
基金supported by funds from the National Key R&D Program of China (2020YFA0707800 to W.W., 2020YFA0707600 to Z.Z.)Beijing Municipal Science & Technology Commission (Z181100001318009)+4 种基金the National Natural Science Foundation of China (31930016)Beijing Advanced Innovation Center for Genomics at Peking University and the Peking-Tsinghua Center for Life Sciences (to W.W.)the National Natural Science Foundation of China (31870893)the National Major Science & Technology Project for Control and Prevention of Major Infectious Diseases in China (2018ZX10301401 to Z.Z.)China Postdoctoral Science Foundation (2020M670031 to Y.L.)
文摘The outbreak of coronavirus disease 2019(COVID-19) caused by SARS-CoV-2 has created a global health crisis. SARS-CoV-2 infects varieties of tissues where the known receptor ACE2 is low or almost absent, suggesting the existence of alternative viral entry pathways. Here, we performed a genome-wide barcoded-CRISPRa screen to identify novel host factors that enable SARS-CoV-2 infection. Beyond known host proteins, i.e., ACE2, TMPRSS2, and NRP1, we identified multiple host components,among which LDLRAD3, TMEM30A, and CLEC4G were confirmed as functional receptors for SARS-CoV-2. All these membrane proteins bind directly to spike’s N-terminal domain(NTD). Their essential and physiological roles have been confirmed in either neuron or liver cells. In particular, LDLRAD3 and CLEC4G mediate SARS-CoV-2 entry and infection in an ACE2-independent fashion. The identification of the novel receptors and entry mechanisms could advance our understanding of the multiorgan tropism of SARS-CoV-2, and may shed light on the development of COVID-19 countermeasures.