The novel severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)is the cause of a rapidly spreading illness,coronavirus disease 2019(COVID-19),affecting more than seventeen million people around the world.Diagnos...The novel severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)is the cause of a rapidly spreading illness,coronavirus disease 2019(COVID-19),affecting more than seventeen million people around the world.Diagnosis and treatment guidelines for clinicians caring for patients are needed.In the early stage,we have issued"A rapid advice guideline for the diagnosis and treatment of 2019 novel coronavirus(2019-nCoV)infected pneumonia(standard version)";now there are many direct evidences emerged and may change some of previous recommendations and it is ripe for develop an evidence-based guideline.We formed a working group of clinical experts and methodologists.The steering group members proposed 29 questions that are relevant to the management of COVID-19 covering the following areas:chemoprophylaxis,diagnosis,treatments,and discharge management.We searched the literature for direct evidence on the management of COVID-19,and assessed its certainty generated recommendations using the Grading of Recommendations,Assessment,Development and Evaluation(GRADE)approach.Recommendations were either strong or weak,or in the form of ungraded consensus-based statement.Finally,we issued 34 statements.Among them,6 were strong recommendations for,14 were weak recommendations for,3 were weak recommendations against and 11 were ungraded consensus-based statement.They covered topics of chemoprophylaxis(including agents and Traditional Chinese Medicine(TCM)agents),diagnosis(including clinical manifestations,reverse transcription-polymerase chain reaction(RT-PCR),respiratory tract specimens,IgM and IgG antibody tests,chest computed tomography,chest X-ray,and CT features of asymptomatic infections),treatments(including lopinavirritonavir,umifenovir,favipiravir,interferon,remdesivir,combination of antiviral drugs,hydroxychloroquine/chloroquine,interleukin-6 inhibitors,interleukin-1 inhibitors,glucocorticoid,qingfei paidu decoction,lianhua qingwen granules/capsules,convalescent plasma,lung transplantation,invasive or noninvasive ventilat展开更多
The effects of saturation on post-peak mechanical properties and energy features are main focal points for sandstones. To obtain these important attributes, post-peak cyclic loading and unloading tests were conducted ...The effects of saturation on post-peak mechanical properties and energy features are main focal points for sandstones. To obtain these important attributes, post-peak cyclic loading and unloading tests were conducted on sandstone rock samples under natural and saturated states using the RMT-150B rock mechanics testing system. After successful processing of these tests, comparisons of stress-strain, strength, deformation, damage, and degradation of mechanical properties, wave velocity, and energy features of sandstone were conducted between natural and saturated states. The results show that saturation has evident weakening effects on uniaxial cyclic loading and unloading strength and elastic modulus of post-peak fracture sandstone. With the increase of post-peak loading and unloading period, the increases in amplitude of peak axial, lateral, and volumetric strains are all enhanced at approximately constant speed under the natural state. The increase in amplitude of axial peak strain is also enhanced at approximately constant speed, while the amplitudes of lateral and volumetric peak strains increase significantly under the saturated state. Compared with the natural state, the increase in amplitude of saturated samples＇ peak lateral and volumetric strains, and the post-peak cyclic loading and unloading period all conform to the linearly increasing relationship. Under natural and saturated states, the damage factor （the plastic shear strain） of each rock sample gradually increases with the increase of post-peak cyclic loading and unloading period, and the crack damage stress of each rock sample declines rapidly at first and tends to reach a constant value later with the increase in plastic shear strain. Under natural and saturated states, the wave velocities of rock samples all decrease in the process of post-peak cyclic loading and unloading with the increase in plastic shear strain. The wave velocities of rock samples and plastic shear strain conform to the exponential relationship with a constant. Saturati展开更多
We consider the sufficient and necessary conditions for the formal triangular matrix ring being right minsymmetric, right DS, semicommutative, respectively.
In this paper, we investigate not only the acceleration problem of the q-Bernstein polynomials Bn（f, q; x） to B∞ （f, q; x） but also the convergence of their iterated Boolean sum. Using the methods of exact estima...In this paper, we investigate not only the acceleration problem of the q-Bernstein polynomials Bn（f, q; x） to B∞ （f, q; x） but also the convergence of their iterated Boolean sum. Using the methods of exact estimate and theories of modulus of smoothness, we get the respective estimates of the convergence rate, which suggest that q-Bernstein polynomials have the similar answer with the classical Bernstein polynomials to these two problems.展开更多
The Mesozoic granitoids in the Dabie Orogen are of particular geological interest as indicators for Mesozoic lithospheric evolution because of their close association with porphyry Mo mineralization. Here, we present ...The Mesozoic granitoids in the Dabie Orogen are of particular geological interest as indicators for Mesozoic lithospheric evolution because of their close association with porphyry Mo mineralization. Here, we present a study using petrogeochemistry data to constrain the petrogenesis of the Xiaofan granites in the Dabie Mo mineralization belt （DMB）, Henan Province, China. Field investigations show that the Xiaofan pluton mainly consists of porphyritic granite. The Xiaofan granites have high SiO2 contents of 74.29 wt%-76.07 wt% （average： 75.18 wt%）, A1203 contents of 11.66 wt%-12.83 wt% （average： 12.13 wt%）, and K20 contents of 5.37 wt%-7.90 wt% （average： 6.86 wt%） and low MgO （0.06 wt%-0.16 wt%）, TiO2 （0.09 wt%-0.10 wt%）, and P205 （0.047 wt%-0.103 wt%） contents. They are enriched in Rb, U, K and Hf but depleted in Ba, Nb, Ta, Sr and Ti. By geochemical and mineralogical features, we propose that the Xiaofan granites belong to A-type type granite and dominantly sourced from the crust. The granites from the Xiaofan Mo deposit may have formed in a post-collision extensional setting.展开更多
It has been about one decade since China takes effect the basic education reform, and this study chooses 14 news reports about Chinese basic education reform in the recent years from both America and China as the rese...It has been about one decade since China takes effect the basic education reform, and this study chooses 14 news reports about Chinese basic education reform in the recent years from both America and China as the research samples, and analyzes the samples from the perspective of critical discourse analysis （CDA） to show whether there are differences in the two countries＇ news reports. The samples in this study are selected from the official websites of the two countries. Among the American news reports, some reports from New York Times and others from CNN; while among the Chinese reports, some are from China Daily and others are from CCTV. Under the theoretical framework of CDA, this paper is based on Fairclough＇s three-dimensional modes, and chooses Halliday＇s systemic-functional grammar as the analytical tool. It aims to reveal the hidden relationship between news reports language and ideology as well as power through the contrastive analysis. Through the analysis it finds out that the power relations and ideologies tend to exist in news reports on the issue of Chinese basic education reform. The purposes of news reports are not only to provide the latest information to readers, but also to influence the readers ideologies and at last even to control the readers＇ ideologies through reading of the very issue展开更多
基金supported(in part)by the National Key Research and Development Program of China(2020YFC0845500)the Special Project for Emergency of Hubei Province(2020FCA008)the First Level Funding of the Second Medical Leading Talent Project in Hubei Province。
文摘The novel severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)is the cause of a rapidly spreading illness,coronavirus disease 2019(COVID-19),affecting more than seventeen million people around the world.Diagnosis and treatment guidelines for clinicians caring for patients are needed.In the early stage,we have issued"A rapid advice guideline for the diagnosis and treatment of 2019 novel coronavirus(2019-nCoV)infected pneumonia(standard version)";now there are many direct evidences emerged and may change some of previous recommendations and it is ripe for develop an evidence-based guideline.We formed a working group of clinical experts and methodologists.The steering group members proposed 29 questions that are relevant to the management of COVID-19 covering the following areas:chemoprophylaxis,diagnosis,treatments,and discharge management.We searched the literature for direct evidence on the management of COVID-19,and assessed its certainty generated recommendations using the Grading of Recommendations,Assessment,Development and Evaluation(GRADE)approach.Recommendations were either strong or weak,or in the form of ungraded consensus-based statement.Finally,we issued 34 statements.Among them,6 were strong recommendations for,14 were weak recommendations for,3 were weak recommendations against and 11 were ungraded consensus-based statement.They covered topics of chemoprophylaxis(including agents and Traditional Chinese Medicine(TCM)agents),diagnosis(including clinical manifestations,reverse transcription-polymerase chain reaction(RT-PCR),respiratory tract specimens,IgM and IgG antibody tests,chest computed tomography,chest X-ray,and CT features of asymptomatic infections),treatments(including lopinavirritonavir,umifenovir,favipiravir,interferon,remdesivir,combination of antiviral drugs,hydroxychloroquine/chloroquine,interleukin-6 inhibitors,interleukin-1 inhibitors,glucocorticoid,qingfei paidu decoction,lianhua qingwen granules/capsules,convalescent plasma,lung transplantation,invasive or noninvasive ventilat
基金Projects（51304068, 51674101, 51374112） supported by the National Natural Science Foundation of China Project（17FTUE03） supported by the Fujian Research Center for Tunneling and Urban Underground Space Engineering （Huaqiao University）, China Project（2018M632574） supported by the Postdoctoral Science Foundation of China
文摘The effects of saturation on post-peak mechanical properties and energy features are main focal points for sandstones. To obtain these important attributes, post-peak cyclic loading and unloading tests were conducted on sandstone rock samples under natural and saturated states using the RMT-150B rock mechanics testing system. After successful processing of these tests, comparisons of stress-strain, strength, deformation, damage, and degradation of mechanical properties, wave velocity, and energy features of sandstone were conducted between natural and saturated states. The results show that saturation has evident weakening effects on uniaxial cyclic loading and unloading strength and elastic modulus of post-peak fracture sandstone. With the increase of post-peak loading and unloading period, the increases in amplitude of peak axial, lateral, and volumetric strains are all enhanced at approximately constant speed under the natural state. The increase in amplitude of axial peak strain is also enhanced at approximately constant speed, while the amplitudes of lateral and volumetric peak strains increase significantly under the saturated state. Compared with the natural state, the increase in amplitude of saturated samples＇ peak lateral and volumetric strains, and the post-peak cyclic loading and unloading period all conform to the linearly increasing relationship. Under natural and saturated states, the damage factor （the plastic shear strain） of each rock sample gradually increases with the increase of post-peak cyclic loading and unloading period, and the crack damage stress of each rock sample declines rapidly at first and tends to reach a constant value later with the increase in plastic shear strain. Under natural and saturated states, the wave velocities of rock samples all decrease in the process of post-peak cyclic loading and unloading with the increase in plastic shear strain. The wave velocities of rock samples and plastic shear strain conform to the exponential relationship with a constant. Saturati
基金Foundation item： Supported by the Fund of Beijing Education Committee（KM200610005024） Supported by the National Natural Science Foundation of China（10671061）
文摘We consider the sufficient and necessary conditions for the formal triangular matrix ring being right minsymmetric, right DS, semicommutative, respectively.
文摘In this paper, we investigate not only the acceleration problem of the q-Bernstein polynomials Bn（f, q; x） to B∞ （f, q; x） but also the convergence of their iterated Boolean sum. Using the methods of exact estimate and theories of modulus of smoothness, we get the respective estimates of the convergence rate, which suggest that q-Bernstein polynomials have the similar answer with the classical Bernstein polynomials to these two problems.
基金Project(2017M622596)supported by the Postdoctoral Science Foundation of ChinaProject(2015CX008)supported by the Innovation Driven Project of Central South University,ChinaProject(12120114052201)supported by the Geological Scientific Research Project of Land and Resources of Hunan Province,China
文摘The Mesozoic granitoids in the Dabie Orogen are of particular geological interest as indicators for Mesozoic lithospheric evolution because of their close association with porphyry Mo mineralization. Here, we present a study using petrogeochemistry data to constrain the petrogenesis of the Xiaofan granites in the Dabie Mo mineralization belt （DMB）, Henan Province, China. Field investigations show that the Xiaofan pluton mainly consists of porphyritic granite. The Xiaofan granites have high SiO2 contents of 74.29 wt%-76.07 wt% （average： 75.18 wt%）, A1203 contents of 11.66 wt%-12.83 wt% （average： 12.13 wt%）, and K20 contents of 5.37 wt%-7.90 wt% （average： 6.86 wt%） and low MgO （0.06 wt%-0.16 wt%）, TiO2 （0.09 wt%-0.10 wt%）, and P205 （0.047 wt%-0.103 wt%） contents. They are enriched in Rb, U, K and Hf but depleted in Ba, Nb, Ta, Sr and Ti. By geochemical and mineralogical features, we propose that the Xiaofan granites belong to A-type type granite and dominantly sourced from the crust. The granites from the Xiaofan Mo deposit may have formed in a post-collision extensional setting.
文摘It has been about one decade since China takes effect the basic education reform, and this study chooses 14 news reports about Chinese basic education reform in the recent years from both America and China as the research samples, and analyzes the samples from the perspective of critical discourse analysis （CDA） to show whether there are differences in the two countries＇ news reports. The samples in this study are selected from the official websites of the two countries. Among the American news reports, some reports from New York Times and others from CNN; while among the Chinese reports, some are from China Daily and others are from CCTV. Under the theoretical framework of CDA, this paper is based on Fairclough＇s three-dimensional modes, and chooses Halliday＇s systemic-functional grammar as the analytical tool. It aims to reveal the hidden relationship between news reports language and ideology as well as power through the contrastive analysis. Through the analysis it finds out that the power relations and ideologies tend to exist in news reports on the issue of Chinese basic education reform. The purposes of news reports are not only to provide the latest information to readers, but also to influence the readers ideologies and at last even to control the readers＇ ideologies through reading of the very issue
