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
As the brightest gamma-ray burst ever observed,GRB 221009A provided a precious opportunity to explore spectral line features.In this article,we performed a comprehensive spectroscopy analysis of GRB 221009A jointly wi...As the brightest gamma-ray burst ever observed,GRB 221009A provided a precious opportunity to explore spectral line features.In this article,we performed a comprehensive spectroscopy analysis of GRB 221009A jointly with GECAM-C and Fermi/GBM data to search for emission and absorption lines.For the first time we investigated the line feature throughout this GRB including the most bright part where many instruments suffered problems,and identified prominent emission lines in multiple time intervals.The central energy of the Gaussian emission line evolves from about 37 to 6 MeV,with a nearly constant ratio(about 10%)between the line width and central energy.Particularly,we find that both the central energy and the energy flux of the emission line evolve with time as a power law decay with power law index of–1 and–2,respectively.We suggest that the observed emission lines most likely origin from the blue-shifted electron positron pair annihilation 511 ke V line.We find that a standard high latitude emission scenario cannot fully interpret the observation,thus we propose that the emission line comes from some dense clumps with electron positron pairs traveling together with the jet.In this scenario,we can use the emission line to directly,for the first time,measure the bulk Lorentz factor of the jet(Γ)and reveal its time evolution(i.e.,Γ~t^(-1))during the prompt emission.Interestingly,we find that the flux of the annihilation line in the co-moving frame keeps constant.These discoveries of the spectral line features shed new and important lights on the physics of GRB and relativistic jet.展开更多
Delirium is a severe acute neuropsychiatric syndrome that commonly occurs in the elderly and is considered an independent risk factor for later dementia.However,given its inherent complexity,few animal models of delir...Delirium is a severe acute neuropsychiatric syndrome that commonly occurs in the elderly and is considered an independent risk factor for later dementia.However,given its inherent complexity,few animal models of delirium have been established and the mechanism underlying the onset of delirium remains elusive.Here,we conducted a comparison of three mouse models of delirium induced by clinically relevant risk factors,including anesthesia with surgery(AS),systemic inflammation,and neurotransmission modulation.We found that both bacterial lipopolysaccharide(LPS)and cholinergic receptor antagonist scopolamine(Scop)induction reduced neuronal activities in the delirium-related brain network,with the latter presenting a similar pattern of reduction as found in delirium patients.Consistently,Scop injection resulted in reversible cognitive impairment with hyperactive behavior.No loss of cholinergic neurons was found with treatment,but hippocampal synaptic functions were affected.These findings provide further clues regarding the mechanism underlying delirium onset and demonstrate the successful application of the Scop injection model in mimicking delirium-like phenotypes in mice.展开更多
Polarimetry plays an important role in investigating physical properties for celestial objects. We present a polarimeter named YFPOL for the Cassegrain focus of the Lijiang 2.4 m Telescope(LJT) of Yunnan Observatories...Polarimetry plays an important role in investigating physical properties for celestial objects. We present a polarimeter named YFPOL for the Cassegrain focus of the Lijiang 2.4 m Telescope(LJT) of Yunnan Observatories, Chinese Academy of Sciences. YFPOL is a traditional single-beam polarimeter with a rotating polarizer. As the focal-reducer instrument Yunnan Faint Object Spectrograph and Camera(YFOSC) is always positioned on the Cassegrain focal plane of LJT, we develop two sets of ultra-thin(thickness <12 mm) polarizer rotation control systems with wireless charging and control functions, which are suitable for mounting on the two front-wheels of YFOSC. One set is used as the polarimetric calibration unit, and the other is for the polarimetric modulation unit. Both of the polarizers have an ultra-high contrast ratio of 1,000,000:1 in the optical band. We investigate the instrumental polarization characteristics(IPCs) in the full field of view that is transferred from YFOSC. Furthermore, we identify that the IPCs change when the Cassegrain axis rotates. The spurious polarization from the IPCs can be effectively minimized by flat-fielding using the unpolarized domeflat, when the Cassegrain rotation angle is the same or nearest to that of the polarization observation. We develop a quasiautomatic pipeline for YFPOL and its effectiveness has been verified by tests of the polarimetric observation with blazar S5 0716+714. The calibration is performed by observing the zero-polarized and highly-polarized standard stars. We successfully reach high precision polarization in the 7’ field of view, and the systematic uncertainty is below 0.8% for a V = 11.68 target with a 10 s exposure. The instrument polarization angle offset is 2°. 6. YFPOL is not only a simple polarimeter, but also a spectropolarimeter with grisms that can be considered in the future.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supported by the National Key R&D Program of China(Grant Nos.2021YFA0718500,and 2023YFE0101200)the Strategic Priority Research Program of Chinese Academy of Sciences(Grant Nos.XDA15360102,XDA15360300,and XDA15052700)+3 种基金the National Natural Science Foundation of China(Grant Nos.12273042,61234003,61434004,61504141,11673062,12393813,2333007,12027803,and 12303045)the CAS Interdisciplinary Project(Grant No.KJZD-EW-L11-04)supported by the Strategic Priority Research Program on Space Science(Grant No.XDA15360000)of the Chinese Academy of Sciencessupported by the Yunnan Revitalization Talent Support Program(Yun Ling Scholar Award)。
文摘As the brightest gamma-ray burst ever observed,GRB 221009A provided a precious opportunity to explore spectral line features.In this article,we performed a comprehensive spectroscopy analysis of GRB 221009A jointly with GECAM-C and Fermi/GBM data to search for emission and absorption lines.For the first time we investigated the line feature throughout this GRB including the most bright part where many instruments suffered problems,and identified prominent emission lines in multiple time intervals.The central energy of the Gaussian emission line evolves from about 37 to 6 MeV,with a nearly constant ratio(about 10%)between the line width and central energy.Particularly,we find that both the central energy and the energy flux of the emission line evolve with time as a power law decay with power law index of–1 and–2,respectively.We suggest that the observed emission lines most likely origin from the blue-shifted electron positron pair annihilation 511 ke V line.We find that a standard high latitude emission scenario cannot fully interpret the observation,thus we propose that the emission line comes from some dense clumps with electron positron pairs traveling together with the jet.In this scenario,we can use the emission line to directly,for the first time,measure the bulk Lorentz factor of the jet(Γ)and reveal its time evolution(i.e.,Γ~t^(-1))during the prompt emission.Interestingly,we find that the flux of the annihilation line in the co-moving frame keeps constant.These discoveries of the spectral line features shed new and important lights on the physics of GRB and relativistic jet.
基金supported by the National Natural Science Foundation of China(82071191,82001129)Natural Science Foundation of Sichuan Province(2022NSFSC1509)+1 种基金National Clinical Research Center for Geriatrics of West China Hospital(Z2021LC001)West China Hospital 1.3.5 Project for Disciplines of Excellence(ZYYC20009)。
文摘Delirium is a severe acute neuropsychiatric syndrome that commonly occurs in the elderly and is considered an independent risk factor for later dementia.However,given its inherent complexity,few animal models of delirium have been established and the mechanism underlying the onset of delirium remains elusive.Here,we conducted a comparison of three mouse models of delirium induced by clinically relevant risk factors,including anesthesia with surgery(AS),systemic inflammation,and neurotransmission modulation.We found that both bacterial lipopolysaccharide(LPS)and cholinergic receptor antagonist scopolamine(Scop)induction reduced neuronal activities in the delirium-related brain network,with the latter presenting a similar pattern of reduction as found in delirium patients.Consistently,Scop injection resulted in reversible cognitive impairment with hyperactive behavior.No loss of cholinergic neurons was found with treatment,but hippocampal synaptic functions were affected.These findings provide further clues regarding the mechanism underlying delirium onset and demonstrate the successful application of the Scop injection model in mimicking delirium-like phenotypes in mice.
基金supported by the National Key R&D Program of China with No.2021YFA1600404the National Natural Science Foundation of China (NSFC, Grant Nos. 11991051, 11573067, 11673062,11527804, U1931206 and 11873091)+3 种基金the CAS “Light of West China” Programthe Yunnan Province Basic Research Plan with No. 2019FA001the China Manned Space Project with No. CMS-CSST-2021-A06funded by Yunnan Province,Chinese Academy of Sciences and NSFC。
文摘Polarimetry plays an important role in investigating physical properties for celestial objects. We present a polarimeter named YFPOL for the Cassegrain focus of the Lijiang 2.4 m Telescope(LJT) of Yunnan Observatories, Chinese Academy of Sciences. YFPOL is a traditional single-beam polarimeter with a rotating polarizer. As the focal-reducer instrument Yunnan Faint Object Spectrograph and Camera(YFOSC) is always positioned on the Cassegrain focal plane of LJT, we develop two sets of ultra-thin(thickness <12 mm) polarizer rotation control systems with wireless charging and control functions, which are suitable for mounting on the two front-wheels of YFOSC. One set is used as the polarimetric calibration unit, and the other is for the polarimetric modulation unit. Both of the polarizers have an ultra-high contrast ratio of 1,000,000:1 in the optical band. We investigate the instrumental polarization characteristics(IPCs) in the full field of view that is transferred from YFOSC. Furthermore, we identify that the IPCs change when the Cassegrain axis rotates. The spurious polarization from the IPCs can be effectively minimized by flat-fielding using the unpolarized domeflat, when the Cassegrain rotation angle is the same or nearest to that of the polarization observation. We develop a quasiautomatic pipeline for YFPOL and its effectiveness has been verified by tests of the polarimetric observation with blazar S5 0716+714. The calibration is performed by observing the zero-polarized and highly-polarized standard stars. We successfully reach high precision polarization in the 7’ field of view, and the systematic uncertainty is below 0.8% for a V = 11.68 target with a 10 s exposure. The instrument polarization angle offset is 2°. 6. YFPOL is not only a simple polarimeter, but also a spectropolarimeter with grisms that can be considered in the future.
